All-glass doors: Stylish separation or joining?
All-glass doors are frameless doors, existing at least of single-layer safety glass (ESG). They represent a stylish alternative to conventional doors and are often referred to as design element with joining properties.
Although it creates a division in the room, the glass door does not have a closing character; it rather adds spaciousness to a room. The product range in the area of all-glass doors is nearly unlimited.
For example, there are matted or varnished all-glass doors or all-glass doors featuring fluted bevels. So-called doors from relief melted glass have their very special appeal.
The glass for these doors is melted at high temperatures and then cooled without any auxiliary means, that is, it is left to itself. The glass thereby receives a new surface structure.
Because this process cannot be influenced, each all-glass door as relief melted glass door represents a very special item, distinct and unique. By the way: All-glass doors are available both as regular door and as sliding doors, swing doors and so on.
Amorphous structures – ordered disorder
Crystals have a highly ordered structure. This makes them the exact opposite of materials with an amorphous structure. Sounds very scientific, and it actually is. We are talking about glass, for example. How are amorphous structures created in glass?
Well, by heating the glass substance until it is liquid and then letting it cool down rather quickly. This process does not allow the atoms in the material which we want to change into an amorphous state to take on an ordered structure. What this really means: The atoms simply do not have enough time to sort themselves.
Scientists describe amorphous structures as having a lower packing efficiency. That means: The relative density of a material with an amorphous structure is significantly lower than that of a crystalline material, so the coarse order of the atoms in the amorphous structure basically creates unused spaces.
But there are also other ways of transforming a material into an amorphous state and creating an amorphous structure, for example through intensive radiation or ion bombardment. Glass, by the way, is a collective term for amorphous structures – an ideal material for processing with laser technology.
Argon ion laser: High performance in the visible spectral range
Have you ever seen a really breathtaking laser show? A true feast for the eyes, right? If you have ever wondered how to use light beams to write delicate patterns into the sky or project them onto an object – here is the answer: Argon ion lasers work really hard while you are enjoying the great show.
Argon is an inert gas which the laser uses in an ionized form. It can make up to ten laser lines visible. These range in the blue, green and yellow-green color spectrum.
Where else are argon ion lasers used apart from shows? In research, for example, or even in printing for high speed printing machines. Argon ion lasers are also used for holograms or
for plotting photographs.
Medicine has recently become a very important field of application. Lasers have become an essential element of dentistry, for example. Laser technology is a quite practical invention which is continuously evolving.
Argon laser – high performance in the visible spectral range
Argon lasers are currently among the most powerful lasers operating in the visible spectral range. They are used primarily in the field of science. But argon lasers also deliver a great performance on show stages.
These are actually argon ion lasers. They are popular for creating light effects, as in the well-known laser shows. Argon lasers or argon ion lasers are usually behind these events.
In medicine, argon lasers are used for ophthalmology, for example. Retina detachments can be treated with this special instrument. Altogether, lasers are quite frequently used for facial surgeries.
Doctors say that they offer nearly painless therapy or nearly painless surgery. It has to be said, however, that lasers leave traces at the point where they interact with the tissue, especially when it is used for obliterations.
B2O3 glass: Resistant and robust
Chemistry is not for everyone. So it is fine if the term “B2O3” does not ring a bell, particularly in connection with glass. Let us have a look: B is boron, O is oxygen.
So the formula indicates two units of boron for three units of oxygen, which produces boron trioxide – B2O3. But whatever is that doing in glass? It practically works little miracles. One is the improved chemical resistance, another the improved strength of the glass.
And then there is also the resistance of this glass to strong temperature fluctuations in either direction. This type of glass is also known as Pyrex glass, for example.
These properties also determine the areas of application for this glass. It is popular in medicine and research as it has one other important feature, as practically all real glass: It does not react to the substances with which it comes into contact.
B2O3 glass is also an important material for the glass processing industry. It can be processed and finished easily using modern laser technology.
Beam guiding – so laser beams find their way
Lasers are used for targeted and highly delicate tasks as well as for common laser cutting. The laser beam is of special importance in this context, which also applies to the beam guiding of the laser.
That does not always have to be straight and without frills. Special mirrors guide the beam to where the laser is supposed to take effect. The beam is usually controlled by a computer.
The corresponding mirrors can be moved individually and guide the beam. Beam guiding is not necessarily a fixed component of a laser. It is integrated into separate assemblies which also have other tasks.
Depending on the power level, the beam guiding unit is equipped with the corresponding mirrors. These units are commonly found in laser systems for industrial use.
Borosilicate – Glass for special requirements
In 1887, Otto Schott developed a very special glass: borosilicate glass. It stands out by its tremendous resistance against acids and alkaline solutions. This makes it particularly suitable for use in chemical and medical laboratories.
Its thermal properties underline this aspect: Borosilicate glass hardly reacts at all to extreme temperature fluctuations by expanding or reducing its circumference. It is both heat and cold-resistance while exhibiting a maximum degree of dimensional stability.
If you are looking for borosilicate or borosilicate glass, you will come across the term Jena Glass. This famous glass, which is nothing else than borosilicate glass, was used, for example, to manufacture drinking bottles for infants. The advantage: no plasticizers, no release of volatile substances, antibacterial effectiveness.
The nuclear industry also takes advantage of the positive properties of borosilicate, especially for the storage of radioactive waste. The radioactive substances are bound in the borosilicate glass through the melting process and thus protected against chemical (acids, alkaline solutions) and thermal influences.
Carbon monoxide laser: More complicated than a carbon dioxide laser
Carbon monoxide is one of the most dangerous, if not the most dangerous of all gases. It is colorless and odorless. Most cases of carbon monoxide poisoning are fatal, as people do not even notice when they breathe in this gas.
Carbon monoxide lasers work with this deadly substance. The performance parameters are similar to those of CO2 lasers, but the output power is lower. Another essential disadvantage: Carbon monoxide lasers have to be cooled with a complicated process.
This is due to the enormous temperatures they generate during operation. This disadvantage and the relatively high costs for the technical implementation have left these lasers no chance against CO2 lasers in the industry, although the performance is quite similar.
Active carbon monoxide lasers are therefore found mainly in the field of optics. Scientists do use this type of laser while it is rather not suitable for industrial use on a larger scale, e.g. for machining glass with laser technology.
Ceramic color coats – high resistance
Ceramic color coats belong to the toughest and most resistant types of coating that can be applied to an object and/or building element. They are marked by high chemical resistance when applied with the right method.
So-called plasma spraying is one option. Ionized and dissociated glass, referred to as plasma by the experts, is mixed here with the desired coating additives at up to 30,000 degree; with other words: The additives are melted onto the surface at these temperatures.
This mix is sprayed with high pressure onto the object to be coated. Because of the enormous temperatures, any material can basically be used as coating, whereby ceramic possesses the best properties and is most commonly used. The plasma spraying method provides a uniformly dense coat.
Chrome coatings in glass processing
Especially in the course of metal coating for reflective purposes and the customer-specific design of glass surfaces, chrome coating in various thicknesses and light transmission grades is used. With reflection grades up to over 50 percent, such mirrors are equivalent to conventional mirrors but are much more robust and resistant at the same time.
Principally, all commercially available flat glass types are suitable for coating with chrome. The areas of the glass not to be coated are first covered using a special procedure.
The chrome layers are then applied step by step. By now, chrome-coated glass is a welcome and versatile design element, for example, for façades and interior design. Filigree shapes, logos or even photo-realistic graphics can be applied to the glass without damaging the glass itself.
The correct ratio between glass thickness and chrome coat is decisive for the functionality of a mirror. One specific area of metal-coated glass surface, for example, are security areas such as interrogation rooms. Experts refer to them as spy mirrors: The glass acts like a mirror from one side but allows seeing through it from the other side.
Chrome coating is also used for insulating glass surfaces.
Clear glass – universally useful
Clear glass is probably the most widespread type of glass, as it offers a range of application options because, as such, this only describes one property: It is clear, i.e. transparent, although this already brings us to the first limitation: There is also white clear glass, if only light white and monochrome.
Simplified, clear glass is an umbrella term which is generally understood, for sheet glass and window glass. In most cases this is so-called float glass, which is produced by pouring molten glass on a metal belt where it also cools. Mirror glass is manufactured like this, for example. Window glass, on the other hand, which is also a clear glass, is drawn.
Where we find clear glass in our surroundings: car windows, window panes, picture frame glass, the small panes on fire alarms and so on. Clear glass is very suitable for finishing and/or subsequent machining. But: The quality of the glass depends on its manufacturing.
CO2 laser: High-performance for various applications
CO2 lasers are not only used in the glass-processing and finishing industry. The medical field has also discovered the benefits of laser technology, for example, when performing complicated surgical procedures where absolute precision coupled by maximum success are required.
At this, the innovative laser technology is not even all that new. The CO2 laser was already developed in 1964.
CO2 lasers with their different power ranges are used, for example, for cutting and engraving thin organic materials such as paper and wood; they can be found in metal processing and have become accepted in the glass industry.
Engraving, bonding or scoring of glass are just some examples. Cutting glass with lasers is considered an especially careful process. The glass is hereby only heated to a certain level without melting it. This means: The structure and thus its integrity is not destroyed.
Did you know that halogen bulbs are sealed with lasers or the ampoules of the pharmaceutical industry are scored using a CO2 laser? Take a look, for instance, at glass ampoules for inhalation solutions. Breaking the ampoules without shattering shall be possible at the scored location.
Colloidal glass coloring
To understand what colloidal coloring of glass means, we first have to look at the term “colloidal” itself. It contains the Greek word for glue. And indeed: Colloidal coloring does involve this.
It refers to particles which are finely dispersed within a medium, but able to move freely. Now let us look at colloidal glass coloring. It is based on metallic salts which are added to the glass batch. Initially they have no effect at all and the glass seems to remain a neutral color.
It is only the subsequent annealing of the glass that allows the metal particles, which were practically stuck beneath the glass surface before, to release, grow and develop the desired color effect.
Initially the particles absorb the incoming light. The larger the colloids, the more intensive their color effect. Colloidal colored glass is also known as “ruby glass”, the pure and true ruby glass.
The type of metallic salts added to the glass batch determine the color which the glass will have to the human eye. Of course the amount of salts also have a decisive influence on the color.
Cooling glass: Quickly or slowly.
We have all experienced this: When you burn your finger on a hot stove, you quickly run it under cold water. That eases the pain and is meant to reduce the degree of the burn – it is meant to accelerate the cooling process.
The only problem with this is that it achieves exactly the opposite because it encapsulates the heat. In a way, the same applies to glass.
When glass enters the cooling phase, it is crucial how quickly or slowly the glass cools down because cooling creates tensions. Depending on the method, a high level of surface tension is generated in the glass because rapid cooling cools down the top layer first.
The heat on the inside is retained for longer. It is encapsulated. This brings us back to the heat which can become encapsulated in human tissue.
Of course it is not just one single factor that determines the time frame for the glass cooling process. The intended use of the glass – the glass type – is important. The thickness of the glass also plays a role.
As a rule, experts say that glass cools down within half an hour to 100 minutes. That is quite a good time for a solid, but it is due to the fact that glass has poor heat retention properties. By the way: Fast cooling creates higher impact strength of the finished glass.
Copper vapor laser – great show effects
Some people really love a good party. And that includes a proper light show. Flashes of light in the mist of the fog machine, laser beams whooshing across the room to the beat of the music, quick as lightning.
These great effects are based on sophisticated technology. And copper vapor lasers are part of this technology. They are perfect for light effects.
Copper vapor lasers are from the group of metal vapor lasers. It is all in the name. They are operated under extremely high temperatures and offer a very high power output.
But not to worry: The high temperatures are not completely transferred to the environment as the actual laser – a quartz tube with a heating coil – has an appropriate insulation.
Mirrors are mounted on two electrodes to turn the light from the quartz tube into a colored laser beam. By the way: Copper vapor lasers are available in different power levels. They all have to be brought up to temperature before operation. And what’s more: It is not recommended to look directly into the laser light.
Crystal glass: Old, refined but by no means crystalline
When you buy a glass from crystal glass, you normally know that you are purchasing a high-quality product. This was already known in Venice in the 15th century, and crystal-clear glass could be produced there.
Per definition, crystal glass is a colorless glass with metal oxides normally mixed into. However, the term is rather misleading because it is derived from rock crystal.
The glass, however, is by no means crystalline but amorphous, that is, a substance where its atoms are not arranged in a clear structure. A true crystal is exactly the opposite: the arrangement of the atoms shows a very clear structure here.
By the way, there is a legal definition as to what the glass must contain to deserve the name crystal glass. In addition to the glass matter itself, the substances include potassium oxide, lead oxide, zinc oxide or barium oxide. The law also stipulates the exact quantitative proportions.
By the way: Do you know “Bohemian crystal glass”? Well, this glass does not contain metal oxide but chalk, that is limestone. As you can see, hazardous ingredients are not a must.
Cutting lasers – top performance with precision
The term “cutting laser” simply refers to laser cutting, as this is where these devices are used. And it also indicates that cutting lasers belong in the group of gas lasers.
In an industrial environment, it is usually CO2 lasers that are used for cutting different materials with the highest precision. High precision because cutting lasers can cut – or rather separate – even the most complex shapes accurately and to a hundredth of a millimeter.
Cutting lasers are usually integrated into a larger work station, a production platform combining several work steps from material to finished component.
The work steps can include cutting with a cutting laser, grinding, punching, drilling (also with laser technology) and other processes. The multifunctional work stations are usually computer controlled.
Cutting lasers can cut and/or separate materials such as metal, glass, plastic or even wood.
Diode pumped solid state laser – DPSS
This is a state-of-the-art development in laser technology which is becoming increasingly popular on the market – DPSS lasers.
These are solid state lasers which are pumped with radiation from diode lasers rather than with gas discharge lamps as before. In short: One laser powering another laser. We would like to point out the special advantages of this laser system:
The pump laser uses only the wavelength with which the laser medium can be effectively excited. This in turn provides another advantage: Less heat is generated.
Gas discharge lamps have a shorter service life than diode lasers. That means: Economic efficiency is increased, even when comparing the higher purchasing costs to the benefit, as these costs are a clear disadvantage of the DPSS laser.
The radiation quality is improved as the decreased heat generation increases the power density.
The so-called electrical/optical efficiency of these lasers is clearly above the level of the previously widespread gas discharge lamps, also referred to as flash lamps.
DPSS lasers are used in glass processing and finishing, among other areas.
Dye laser – one of the most important laser types
Dye lasers are one of the most important types and were the leading models of tunable lasers for a long time. They have now been replaced by tunable diode lasers, for example. Their advantage: They are easier to handle.
Dye lasers are based on a dye dissolved in a liquid, e.g. water, which serves as an active medium. Dye lasers are used especially in the scientific area of laser spectroscopy due to their many positive properties.
The problem with these lasers: They involve high purchasing costs and are very complicated and expensive to run. This is also the reason why newly developed lasers which have a comparable performance and are easier and less problematic to handle have gradually been replacing dye lasers.
One area of application of dye lasers is medicine, for example, primarily dermatology. Specialists use the lasers for treating skin conditions and diseases. In this area of medicine, heat and how far the laser penetrates into the tissue play an important role, though.
Single-layer safety glass (ESG): To protect against injuries
Have you ever observed how the side window of a car burst? You will then know the phenomenon these windows disintegrate into thousands of small parts with dull edges, quite differently from conventional glass.
Such glass fragments would normally cause unpleasant to dangerous and deep cut wounds. We are now talking about so-called ESG, that is, single-layer safety glass.
It belongs to the flat glass category. It receives its particular properties through a special method. The glass is heated beyond the point where it could be shaped.
Once this point is reached, the glass is exposed to severe cold and cooled down very rapidly to cause the areas close to the surface to cool faster than the core is able to. If you remember your physics lessons, you will know the result: Tensile stress develops in the core and compression stress on the surface.
This turns simple flat glass into single-layer safety glass. This glass is not only insensitive to major temperature fluctuations but also exhibits enormous impact strength. By the way, this is tested with the pendulum test according to DIN EN 12600.
Excimer laser – medical helper
How are the holes in ink jet printer cartridges made? With a drill. Wrong. A laser takes care of these tiny openings. To be more precise: An excimer laser from the group of gas lasers.
One might think that this is a laser drill then. That is not completely wrong. Our laser works with electromagnetic radiation in the so-called ultraviolet wavelength range – an extremely precise tool for the most delicate tasks.
That is why this laser is also very popular for medical applications: Excimer lasers can be used to correct short sightedness while being quite gentle on the eye. They work with extreme precision and heat only the working area. But these lasers can also cut human tissue.
Again the advantage: The tissue surrounding the cut is not heated. Wound healing is not accompanied by the usual severe pain. Excimer lasers have already become firmly established in other areas of medicine as well.
They can be used to combat psoriasis or neurodermatitis. Other areas of application of these lasers are photolithography, for example. This is a method for producing highly integrative semiconductor components.
Fibre laser – optical fibre at the core
Fibre lasers are basically glass lasers. That is why experts also refer to them as a special type of solid state laser. This solid consists of the so-called doped core of a glass fibre as the active medium. It serves as a waveguide in a figurative sense as it effectively amplifies the laser radiation.
A fibre laser with a medium power level can be used for marking components, for example. Fibre lasers are also used in medicine. And as these lasers are available in a variety of power levels, the areas of application also range from data transfer in the lower power range to cutting or even welding of materials in the higher power range.
The origins of fibre lasers go back to the year 1961. Back then, Elias Snitzer recognised the benefits of a glass laser when he was working on the propagation of radiation in glass fibres. He is recognised as the founder of fibre laser technology.
Flat glass processing machines:
Cutting, bending and coating
The term flat glass covers all types and grades of glass in the shape of a glass sheet. This includes, for example, pre-stressed glass, float glass, laminated glass, insulating glass, fire protection glass and so on.
The flat glass sheets are processed and finished, for example, on flat glass processing machines. They constitute hi-tech machining stations, often combining several process steps, such as water jet cutting and edge finishing.
The BAZ 1 is an example of such a machine for vertical glass processing. It is able to cut sheets up to a thickness of 80 mm with precision and cleanly, and its 20-unit tool changer makes it very diverse.
The BAZ 1, a CNC flat glass processing machine, cuts sheets from the size 550 x 200 mm to 8 000 x 3 300 mm, polishes, scores and finishes the edges of the future product – all this fully automatic. The KBU edge finishing center represents another flat glass processing machine. This CNC machine enables a specialist shop to finish the edges of a wide variety of flat glass, that is, to grind and polish them.
It does not matter here whether flat glass shall be used for building construction, interior design or even solar modules. The difference to conventional machines: The KBU is able to finish sheets all the way around, i.e. one machine for the entire glass sheet. This reduces the work process up to 50 percent.
Float glass: perfection produced by floating
The term already explains: Float glass actually describes “floating” glass. This does not refer to a boat made from glass but the manufacturing process of the glass. Float glass simply refers to flat glass literally produced while floating.
Float glass is manufactured continuously. Pure glass melt is introduced into a bath of hot tin at a temperature of 1,100 degree Celsius. One needs to imagine this bath to represent a liquid conveyor belt where the glass is introduced at one end.
The hot pasty glass matter is markedly lighter than tin. It floats on the surface and can spread like an oil film. A so-called glass film then forms on the tin. While travelling from one side of the belt to the other, it cools down to about 600 degree.
The glass is already firm now and can be carefully cooled down in an appropriate “oven”. Quite contrary to the common hectic pace, slowness is called for here. Cooling the glass too quickly would cause tensions in it.
At the end of the process, the glass is cut to the standard size for flat glass sheets. The special feature in manufacturing: The surface tension of tin and glass provide for a very smooth and clean glass surface.
Float glass has thus meanwhile become the most used basic glass for nearly any application. It can now be processed further with the various flat glass processing machines.
Floated flat glass – float glass in sheets
Flat glass is simply a glass pane – no complicated hollow bodies, no other shapes, simply a flat sheet of glass. It does not matter initially what type of glass it is. But when we are talking about floated flat glass then it is float glass in sheet format.
So let us find out what characterizes float glass. The term “float glass” indicates a floating process during manufacturing of the sheets. The liquid glass is fed into a tin bath which is also hot.
This process runs continuously: That means: The tin bath acts as a kind of conveyor belt, albeit a liquid one. And that only works because the hot glass is lighter than the tin. So it actually floats.
The reaction of the glass with the tin creates a clean and fine glass surface. During the bath, the glass cools down. While the glass is fed into the tin bath at one end, the now solid but not yet annealed glass is cut into sheets at the other end. This produces sheets of float glass.
Fluorescence: When light reacts with a solid
Fluorescence creates fantastic light effects. They occur when light excites a material and causes a reaction. The material initially absorbs the light and returns it in a weakened and altered form.
Such a spectacle does not always have to be created artificially. Nature is pretty good at that without our help. Just think of the famous glow worms. The male insects use their fluorescent abilities to impress their female companions. And they seem to succeed year after year.
We also encounter fluorescence in daily life. For example, it is the basis for the function of an energy saving bulb. Displays are also based on the phenomenon of fluorescence.
And as the light effects are so impressive, are naturally also used for shows, wallpaper, stickers and large area decorations.
Science has been using the effects of light and solids for a long time. Fluorescence is used, for example, to make hidden traces of bacteria and other contaminations visible under UV light.
Gas Laser
Can you remember? The optical resonator is basically the heart of a laser. In a gas laser, it consists of two mirrors and gas as the active medium. All this is placed inside a glass container which is mounted between the two resonator mirrors.
Simply said, a lamp is installed underneath the container. One mirror – the high reflector – reflects 100 per cent, not leaving a trace of light through, while the other one – the output coupler – is semi-transparent. When the gas laser is activated, the experts light up the lamp.
This light from the lamp is absorbed by the gas and transferred back and forth between the mirrors, with a portion of the light being transmitted through the outside through one mirror. In the end, this small portion is the laser beam.
Gas lasers are an all-round talent as they can be used for a variety of purposes. In the industrial sector, for example, they are used for cutting in glass processing and finishing.
Now you also know how effective the tiny portion of light is that passes through the semi-transparent mirror. This is amplified again, though. Other areas of application for gas lasers with various power levels and specifications are in medicine and research. The term “gas laser” merely describes the function principle of the device.
Glass: Design element with practical use
What is glass? You are probably thinking about the pane of your window, your car or the glass insert in your door? Correct, this is all glass. But did you know that basically any material can practically be transformed from the liquid or gaseous state into glass.
This is achieved by rapid cooling. This is referred to as meta-stable glass, meaning nothing else but a very unstable material.
Glass as such is actually only a collective term for a group of so-called amorphous solids. These are materials where their atoms do not exhibit any clear structure but appear rather with irregular patterns. The opposite would be crystal.
The term “glass” has a Germanic origin. It is used to describe something glossy, shiny. Glasa, that which shines. Today, glass is found in nearly all areas of daily life.
Just think of the simple drinking glass, the glass bottle, glass ampoules from the medical field, entire glass façades, glass plateaus, and so on. To turn simple glass into this advanced modern and extremely stable material, various processing and finishing steps with the respective glass processing machines are required.
Glass ceramics: The material Ceran® glass-ceramic cooktop panels are made of.
Anybody interested in a new kitchen or cooking at the stove at home knows the term: Ceran® glass-ceramic cooktop panel. But: Do you know what this term actually represents?
It is simply a brand name for a glass-ceramic cooktop panel. Glass-ceramics, simply put, is a compound material. Its components: Glass and crystals.
Glass-ceramics is manufactured from molten glass under controlled crystallisation. The material is finally subjected to a special thermal process to give it its special characteristics, because: Glass-ceramics is primarily used where high resistance at major temperature changes is required.
In the industrial field, this is important, for example, with ultra-modern and sensitive laser systems. In the household, the cooktop panel from glass-ceramics is especially known. In addition to the insensitivity to temperatures, glass-ceramics must also be rather impact-proof.
Glass coating for professionals
Glass coating is also a collective term for the various methods and types of coating. Machines handle coating in the industrial sector.
The machine can thereby be adjusted to the respective glass and its future use, because these two factors are decisive on the type of coating. Here a few examples: Let’s take a look at nano coating: It is primarily applied to glass surfaces exposed to the daily weather and difficult to reach for cleaning. Glass façades are a good example. Nano-coated glass is also referred to a self-cleaning glass.
Anti-glare coating: The purpose of this form of coating is to prevent glare from the effects of light. This may be advantageous in traffic, for example..
One fact is important with all types of coating: It must be applied uniformly and consistently to the glass to allow it to display its full effect. The coating must not become detached on its own and that means: Coating actually becomes a bond with the glass itself.
Glass coloring: Rare earths for fine colors
Glass is not only available in a variety of shapes and for many different applications, glass also comes in many different colors. Glass coloring takes place during the manufacturing process.
One option for coloring glass is to add iron oxides. Depending on the type of substance added, the glass takes on a specific color: Sulphur turns the glass yellow while copper oxide or gold turn it red, chromium oxide and iron oxide produce a green tint, and so on.
In addition to oxides, rare earths can also be used for coloring glass. And sometimes a contamination in one of the glass ingredients even creates an unwanted color in the glass. In these cases, the principle of complementary colors is applied.
An opposing color is added to neutralize the unwanted color. Glass coloring requires experts with a great deal of experience. In an industrial environment, computers calculate the correct mixing ratio.
Glass components – so what is actually in glass?
According to the glass industry and the German Glass Industry Association, most glass components in their raw state – the raw materials for glass – come from Germany. This would be a very strong point for the ecological balance sheet of glass as a product.
Origin as well as extraction and transport of the glass components influence this balance. But that is a very wide field and this brief article could only treat it very superficially. But what is glass actually made of? What are the components of glass? It should be six essential elements.
The largest part is made up by quartz sand with 70 per cent. It is hard to believe, but to this we add lime and soda, potash and feldspar as well as dolomite. This makes up the basic batch for glass.
The exact mixing ratio of the batch depends on the manufacturing process and the desired properties of the glass. And how is used glass recycled? Old glass is crushed, processed and added to the batch as an additional glass ingredient. Here again the ratio depends on the final product, of course.
Glass corrosion: When fine glass loses its luster
Glass corrosion is a completely normal process that occurs over time, or at least it used to be. For now we add substances to glass which prevent corrosion or at least delay it. But what is glass corrosion actually?
Well, basically nothing other than rust. But that usually appears red-brown? Correct, and glass which lay buried in soil for century’s shows rainbow colored structures on otherwise transparent glass.
But the term “rust” is only used to illustrate the concept of glass corrosion. It could also be called glass burn, glass disease or glass pestilence. All these terms only describe glass corrosion. What we are referring to is a slight change in the texture on the surface of the glass.
This change creates the visible weathering, which only takes place on the surface, though. Experts have found out that this process initially releases oxides from barium, sodium or potassium. This inevitably leads to a change of the physical properties – a prerequisite for the subsequently visible rust on the glass, the glass corrosion.
How intensively it progresses depends greatly on the substances affecting the glass. By the way: Glass corrosion also occurs in everyday life – on your own glasses when you put them in the dishwasher.
Do not let the advertising promises of the detergent manufacturers lead you on. Glass corrosion that occurs in a dishwasher is rather due to the glass quality, and: Try rubbing two glasses together. You will be surprised at the marks this can leave.
Micro-cracks with mechanical glass cutting
Micro-cracks may develop when glass is cut mechanically. They go along with the risk of breakage of the cut glass.
This fact applies to all mechanical methods, also those the do-it-yourselfer or hobby enthusiast may apply at home. You probably know these small glass cutters used to handle thin plates.
The problem of shattering, especially with heavily stressed glass, is not the only issue. Glass requires subsequent finishing when cut mechanically. For examples, the edges must be polished by elaborate means.
This post-processing ties down resources and causes unnecessary costs. Cutting glass with a laser system is much more effective and easier for the material.
The special highlight: The glass is not damaged with this method. No subsequent finishing is therefore required. And what’s more: The precision of lasers is unparalleled.
Decolorizing glass removes green casts
Sometimes contaminations creep into the glass during the production process. It only takes a slight impurity in a raw material or additive which will act as an unwanted coloring element in the batch. This is where decolorizing comes in.
What this means: The glass is purified during the production process already. If this is not done, the precious glass might end up with a green cast in the end. Not everyone likes such a shade, for example in their window panes.
Decolorizing glass is actually a coloring process, as the method uses the principle of complementary colors. That means: One color balances out another color shade to neutralize it to the human eye. So another coloring substance is simply added to the batch. Glass decolorizing is therefore a bit of a myth, really. Counter dyeing or neutralization would be more suitable terms.
Glass drilling: Patience is required.
Glass can be drilled. In industrial applications, this is handled by hi-tech machines operated by appropriately trained experts of glass processing and finishing. These glass processing machines are meanwhile often part of entire machining stations.
They handle several work steps and are controlled by a computer (CNC). The question is: Can the do-it-yourselfer also drill a hole into glass? Yes, this can be done.
This requires the glass plate, an absolutely flat wood plate and a diamond drill bit. Having an appropriate fixture that ensures the drill bit contacts the glass absolutely perpendicular would be helpful.
Drilling generates heat. This applies also to drilling glass. A little bit of water or gun oil should therefore always be available as coolant.
But care is required: If cooling takes place too rapidly, tensions may be created quickly causing the glass plate, which has just been exposed to stress, to shatter. If you want to drill glass yourself, this should be done slowly and carefully.
Start with a small drill bit and expand the hole bit by bit. This may prevent material shrinkage. If unsure, one should rather contact a specialist shop to handle this task
Etching glass: Beautiful motifs and structures
Patterns and matting in glass are usually achieved by sandblasting or the etching method. So-called etching acids, also hydrochloric acid or etching crème are used.
These methods are also available for domestic use but are not without danger.
Just think about coming into contact with hydrochloric acid. In large-format processes, the areas of the glass not to be treated are sealed first. The glass is then exposed to the etching acid.
Etching glass with laser technology represents a much more effective and exact method while protecting the environment and material. No dangerous chemicals are used here and no pressure is applied to the glass; this means: Even very thin glass, including full bottles, can be furnished with detailed filigree motifs. “Etching” glass per laser becomes increasingly accepted.
Classy, easy to maintain and functional: Glass façades
Glass has captured the field of architecture. Whether for interior areas, design element or curtained façades: Glass is a versatile building material and, at the same time, exercises its protective effect in the area of façade design.
Glass façades are offered as so-called component systems. This means: Glass elements as well as spacers and track systems are perfectly coordinated.
While glass elements for façades used to rather function as design elements, the building material glass meanwhile also contributes energy efficiency aspects: Glass helps the building to score solar benefits, although, this may be problematic in the summer. Glass façades with thermally insulating effects are therefore meanwhile available.
What’s more: The market also offers self-cleaning elements, that is, nano-coated glass. Dirt particles do not stand a chance with this glass. They are also referred to as dirt-repellent glass surfaces.
Refined and cleaned? Glass fining
In everyday life, something is refined when it is free from imperfections or defects. We also speak of refined people, who are elegant, polished and cultured.
With regard to removing imperfections, the term is also used in glass production. The process is referred to as glass refining or fining. It simply describes the removal of bubbles from the molten glass, as of course bubbles in the finished glass would constitute a defect. Basically, small bubbles are swept along by larger bubbles as these rise to the surface more quickly. A fining agent is added to the batch to make this work.
Experts differentiate between two basic methods: chemical fining and blow fining. The latter involves a gas being blown into the glass to reduce the number of bubbles in the glass. The chemical fining process is the one described above. Glass fining is also said to be possible with ultrasound.
Glass finishing – a bit of individuality
Glass finishing is a wide field, as there are virtually no limits to the imagination. Etching, grinding, laser treatment, firing, coating, printing … Glass can be finished in many different ways.
Industrially, the type of glass finishing depends more on the intended use of the respective glass product. Surface, window panes, mirrors, glass dividing walls, façade claddings, etc. – all these are not just simple glass but especially finished products. A craftsman technique for glass finishing is glass milling.
This creates engravings and even entire images in the glass surface. The disadvantage: Almost all types of glass finishing damage the glass, but at least the surface.
Modern laser technology can change that. It can also be used for perfect glass engravings and even internal structuring without damaging the glass surface. As glass is becoming an increasingly interesting production material, glass finishing has a great future.
Glass in electrical engineering: The perfect conductor?
Yes and no, as glass as such is a rather poor conductor. That means: It could also be used as an insulator. The problem why glass is not used as an insulator in electrical engineering is probably its fragility. Porcelain is much more sturdy, although shatter-proof glass is available.
But back to our topic: Where is glass used in electrical engineering? Common lamps are the most well-known elements. They usually consist of glass which is more or less transparent.
Glass plays a special role in modern electrical engineering. One example is intelligent glass. Experts refer to it as electrochromic glass. That means that the light transmission coefficient is changed through the applied DC voltage: The glass changes its level of transparency under voltage. At three Volts, for example, the glass turns blue.
When the voltage is changed or removed from the glass, it changes color again. Against this background, glass has many applications in electrical engineering: A touchscreen, for example, is basically a very thin coated glass pane.
It reacts to heat and when it is touched, it reacts to the very weak electrical impulse created. A state-of-the-art laser can be used to project shapes, writing and symbols into the glass which only become visible when light shines on the screen and/or voltage is applied. So glass should be the material of the future.
Glass marking: Product tracing and type designation
A product that is marketed nowadays must normally provide proof of a continuous history: The finishing industry and consumers shall be able to trace the source of the product. This applies also to glass.
However, glass is not only marked for the purpose of traceability. Experts can determine the type and use of the glass based on the marking.
Until recently, codes were imprinted to the glass or applied to it with the mercury vapor method. However, this has shown not to be very durable. So-called laser fracking, generating minute optical faults in the glass matter – appearing eventually as codes, are much more effective and durable.
Float glass, amongst others, is marked in this manner. Laser technology now also allows glass to be marked on the surface. In this manner, quality seals or QR codes can be integrated in the glass at inconspicuous locations.
Matting glass: Via sandblasting, with acid or using laser.
Glass is normally matted with the sandblasting method. Fine sand is blasted under pressure onto a clear glass surface. This creates a uniformly mat glass surface.
If decorative elements shall be applied to the glass in this manner, templates for the respective décor must first be fabricated and affixed. The area to remain clear is first taped off. Experts refer to this as masking.
Etching technology is another method of matting glass. Different approaches are available and depend on the desired results.
Do-it-yourselfers can also mat glass. This is achieved with special drill attachments and at low to medium speed. The glass is basically roughened.
Laser technology is meanwhile used as well to mat glass. The clear advantage: Masking with the help of a template is not necessary if motifs shall be applied to the glass.
What are glass objects?
A note for starters before taking a look at glass objects: Glass is not necessarily limited to what is commonly referred to as glass, that is, window panes, drinking glasses and other objects. Plexiglas®, for example, is also referred to as glass and is definitely not a product produced with the so-called floating method.
Plexiglas® is cast or extruded. This type of glass is therefore defined as GS or XT glass.
Let’s now turn to the glass objects: What are glass objects then? These are objects of all types that may have been manufactured from any type of glass and subjected to different processing and production methods.
Both, the practical and economic benefit as well as the artistic aspect may thereby stand out. Glass objects can add something to an ambience or blend together with it.
Glass objects stimulate, separate, connect and complement. By the way: Laser technology has advanced meanwhile to a point where artistic glass objects, such as sculptures, can be manufactured with it.
Imprinting glass: Everything is possible.
Meanwhile, nearly any material can be imprinted, naturally also glass. Whether over its full surface or partially: Imprinted glass is always quite impressive.
The appeal of glass panels is rising, for example, in the kitchen where they are used instead of the customary tiled walls, of course, imprinted with the fitting preferred motif. Pictures printed directly on glass and mounted to the wall have a special attraction to many people.
The applications for printed glass are as varied as those of the glass itself. They include privacy screens, glass doors, dividing walls, table tops and so on. The many ways of adding a special touch to the glass are just as diverse.
Glass is normally printed with the silk screen printing method. Although the view is restricted, the glass does not need to become entirely non-transparent.
Glass processing in form, color and structure
Glass processing has many faces. At this point, we first distinguish between processing of class at the small home-based shop, artistic processing of glass in special artisan shops and industrial glass processing with state-of-the-art machine, many of which are CNC-controlled.
With glass processing, the different glasses are prepared according to their future use. Glass processing includes cutting, polishing, milling, matting, etching, structuring, printing, shaping and so on.
The processing methods are just as diverse today as the glass products themselves. Glass processing with machines takes place in so-called processing centers, which are usually able to perform more than a single process step.
The raw piece of material is fed to the machine and the desired finished product is the result. This is possible through sophisticated computer systems, which are able, for example, to control glass processing per laser.
Laser technology in glass processing has meanwhile become a standard approach; after all, it is much more effective, easier on the material and more exact than conventional processing methods.
Glass processing machines
Hi-tech processing centers
You probably know those large saws used at the home improvement store to cut wooden panels to size? The panels are clamped onto a rack.
You can imagine a similar setup for glass processing, except that no heavy-duty circular saws “eat” with much nose through the glass. Quite to the contrary: Laser technology is often used to cut glass to the desired dimensions, of course, all this computer-assisted and controlled.
But this is only one tasks of glass processing machines. Today, they polish the cut right away, grind, mill, engrave, structure, score, sandblast and drill. A single machine thereby often handles more than one task.
These are glass processing centers turning the raw material glass into the desired product via a sophisticated control system.
Laser technology has increasingly become the number one also in the area of glass processing centers. It protects resources much more than conventional methods.
Glass production: From traditional craftsmanship to industrial processes
Glass production is an old trade which required a great deal of specialist knowledge as well as a high level of manual skill. We are not talking about the manufacturing of flat glass, for example for window panes. Certainly that is an art in itself, as it does not depend only on the right mixing ratio.
The real skill is to turn the liquid glass into a product. But let us look at modern, industrial glass production. It is fully automated and takes place in seven steps.
Let’s get started: First the batch is prepared. The glass materials are weighed and mixed well. Then these are transported in a container on a conveyor belt and into the furnace.
In the oven, the batch is melted at about 1,200 degrees Celsius. These high temperatures are required to ensure that all materials react with each other to form the molten glass.
The problem: Bubbles will form. Just a normal part of the process, the experts say, and refine or “fine” the glass. There are special agents for glass fining. Essentially these are based on the principle that small bubbles are swept along by large bubbles which rise more quickly. The fining agent forces this process.
After fining, the glass is shaped. The details of this step depend on the type of glass that is produced. Then the glass is allowed to cool down.
Depending on the glass type and intended use, this takes between half an hour and the length of a football match with one extra time of about 10 minutes. Once cooled, the glass is examined by quality control.
If there are any defects, it’s all over for the glass: It is crushed, processed and reintroduced into the manufacturing process. Finally the finishing: There are different ways for glass finishing, including modern laser technology.
Sandblasting glass: Common finishing method
You thought sandblasting is only used to remove ink coats and coarse soiling? Wrong. Especially with glass finishing, sandblasting is a proven method to give the glass a very unusual accent.
They include mirrors, all-glass doors, dividing walls from glass or window panes: There are many options and hardly any limits to the creativity both of professionals and hobby amateurs.
Sandblasting glass belongs to the area of glass finishing and is used, for example, for surface matting of glass.
With penetration blasting, actual contours, shapes and structures are obtained in the glass. Did you know that sandblasting does not necessarily use sand in the conventional sense?
There is actually a wide variety of materials used for sandblasting. Here just a few examples: Glass beads, nutshell granulate, corn cob pellets or even ceramic beads.
The term sand is always used here since the materials, because of their graininess, exhibit similar properties as sand, however, their effect on the object to be blasted varies widely.
Glass stripping: One method, two objectives.
When talking about glass stripping, this complex term normally refers to the stripping method via CO2 laser. The surface of a glass element is stripped layer by layer; this may also relate to a coat of varnish or other coating.
In this case, this would represent cleaning of the glass. The actual stripping of glass rather describes a production process also performed with the use of CO2 laser.
The glass element is here returned to its raw form layer by layer. Next, the laser polishes the surface of the glass without stripping additional layers.
In the next step, minor shape deviations from the requirements are corrected through fine-stripping. This is also performed per CO2 laser.
Clear structures with laser technology
Glass finishing without laser technology is no longer thinkable. It is also used for structuring glass surfaces.
A difference must be made here, however, between processes that are applied at the homeworker shop and the industrial processes. Structuring primarily means to process the glass surface so that clear contours become apparent, that is, structured unevenness’s.
Experts distinguish between knob-type structures and well-type structures. To achieve structures also on larger glass surfaces, scientists have developed the so-called three-beam interference technology.
The special feature is the division of a laser beam into three spatially arranged single beams superimposed at a defined angle. Different structures can be produced by changing the direction of polarization of the individual beams.
Glass surface finishing:
From etching via laser applications to sand-blasting
When referring to surface processing of glass, this is a collective term for different methods, processes and results. The basic fact is: Glass can be processed from all sides
It does not make any difference here whether the actual glass surface or the edge of a glass surface is meant. In the course of surface finishing, reference is made to methods stripping material, that is, removing partial or complete layers of glass.
Different effects such as matting or glass structuring, are then created depending on the method. Experts differentiate with glass surface processing, for example, between sandblasting, etching – a chemical process – and crackle finishing.
Glass surface processing with laser technology is considered especially effective, exact as well as easy on the material and the environment.
Helium cadmium laser: Dangerous for humans.
You should not get in the way of their beam. Helium cadmium lasers are categorised as laser safety class 3B which means: contact with eyes and skin is not recommended.
In short: Working with this laser requires appropriate protective measures. In principle, this laser is a completely tight tube filled with a helium cadmium gas. This tube works in the blue and ultraviolet spectral range.
It can generate two wavelengths which are measured in newton metres: 325 and 442. The 325 line is not visible to the human eye, but leaves a blue spot on many materials. This is due to fluorescence.
Helium cadmium lasers are generally not used commercially. They are simply too expensive and the service life is far too short for the price. Experts assume 10,000 operating hours. They can be found in cancer prevention and they can be used for generating holograms.
Helium neon laser: Good value and durable
Laser technology has evolved into a very wide field. The progress of development increases the number of different laser types. It therefore happens that several lasers have similar or the same areas of application.
One of these types is the helium neon laser. These can be found sporadically, e.g. in the bar code reading unit of supermarket tills or in laser printers. But they have now been replaced almost completely by diode lasers.
In contrast to helium cadmium lasers, these consist of a glass tube with a length of several tens of centimeters. This is also called a capillary tube. This thin glass element is filled with a gas mixture of helium and neon.
The resonators in this laser are two mirrors which are mounted at either end. Helium neon lasers provide a long service life and are relatively cost efficient to purchase. They are popular for holographic effects.
High pressure laser for top performance
High pressure lasers are actually CO2 lasers which belong to the group of gas lasers. These units work with carbon dioxide under enormous pressure. This is required to achieve the necessary high radiation output.
Carbon dioxide lasers are some of the most important lasers overall. You may have read about them in various job advertisements. The term CO2 laser is sometimes used there, referring to these carbon dioxide lasers.
Specialist companies use these for cutting different materials, such as glass or various metals, as it provides continuously high power. These types of laser are usually integrated into state-of-the-art machining centres which carry out more than just one work step in the machining process.
Cutting, welding, drilling, bending and so on…. These lasers are also used for hardening and finishing different materials.
Hybrid laser: Economic and precise.
Hybrid always refers to the interplay of two forces where one is generated by the other or at least benefits from the other force. Just think about hybrid drives for passenger cars.
The driving motion produced by a combustion engine supplies an electric motor, which in turn helps the combustion engine accelerate.
In this way, the combustion engine requires less force and thus less energy and finally, less fuel. A hybrid laser simply refers to the combination of MAG welding with laser welding.
These machines thereby work at higher temperatures entering precisely and deep into the material to be processed. Much welding material, such as welding metal, can be saved this way.
In addition, hybrid lasers work many times faster as conventional welding machines. But the term hybrid laser is not used only for industrial welding of steel – for example, for machine and plant construction or vehicle manufacturing.
It is also used in regard to engraving and GPS-controlled distance measuring devices.
Hydrolytic glass: Highly resistant glass
Hydrolysis describes the breakdown of a chemical or biochemical compound through reaction with water. So far, so good. But was that have to do with glass? Can hydrolytic glass break down a chemical compound? And what role does water play in this?
Well, hydrolytic glass is simply resistant to chemical and/or biochemical reactions. That means: It does not react itself, it remains neutral and resists the attacks from the compounds and the reactions between water and the chemical compounds.
A special measuring method determines the scope of this by categorizing the individual glass types. This classification is important as it classifies the glass types for use in medical laboratories or in other facilities where acids, bases and other substances are handled.
Borosilicate glass, by the way, is not only highly resistant to strong and fast temperature fluctuations. It is a hydrolytic glass and is therefore resistant to acids, bases and their reaction with water. More simply: This glass can withstand the influence of chemicals.
Industrial flat glass processing:
From volume to exclusive.
Flat glass is the basis for many end products used in daily life. Whether in the shape of window panes, glass doors, façade elements, stairs, railing, room dividers, furniture and other objects: Apart from stainless steel, flat glass is the top stylistic element: unobtrusive or adding visual accents.
When talking about processing, industrial flat glass processing is meant. This is done on modern machines; machine centers are able to combine several process steps with flat glass processing.
Cutting and finishing glass edges is one example. The flat glass sheets are cut to size on state-of-the-art CNC machines. Lasers are especially effective.
While with common processes the vicinity of a cut can also be damaged, e.g. through fine hairline cracks, this is not possible with laser cutting. This also means then that subsequent finishing of the edges can be completely dispensed with or handled significantly faster.
Industrial flat glass processing includes fluted bevels in the glass surface, UV-bonding of flat glass, bending of glass, matting, coating and printing on flat glass. Ultra-modern and efficient industrial lasers can be employed for nearly all forms of industrial flat glass processing.
Industrial laser processing: Versatile tasks
We’d like to point out again: industrial laser processing of materials is highly versatile. Actually, any common material can be processed with a laser instead of the conventional methods.
The advantages are obvious: A laser works highly efficient, preserving material and the environment. Although laser technology may involve higher costs when initially purchased, it amortizes itself through daily use.
Here some examples of industrial laser processing of glass and metal, respectively steel. Laser cutting: When cutting glass by conventional means, the glass may sustain damages in the edge zones.
At any rate, the edges need to be finished. When cutting glass with a laser, the subsequent finishing time is considerably shorter because: The laser separates the glass exactly at the point intended without damaging the vicinity.
Laser welding:
The term laser welding is also often used in the context of industrial laser processing. This process is used, for example, with machine and plant engineering as well as in the automotive industry.
Its advantage: More shallow welds through the penetrating effect of the laser, less welding material, time-savings. There are many additional examples for industrial laser processing. To list them all here would go beyond the scope.
Insulating glass: Protection against noise, heat and cold
The term is self-explanatory. Insulating glass literally possesses insulating properties; it basically partitions a room from its environment without giving the feeling of separation… because glass for windows and doors is normally transparent, unless it has been matted, structured or imprinted with special laser processes.
Insulating glass stands for: Sound protection, safety, heat and cold protection and, if coated accordingly, glare protection. Simple insulating glass consists of two sheets with an enclosed hollow space between them. Experts call this an enclosed building element.
This type of insulating glass is nowadays considered the basic standard. To meet the specifications of the Energy Act, triple glazing is often used now in home construction. This is a requirement especially for passive, plus-energy and zero-energy homes.
The hollow spaces between the sheets are filled with a special gas to increase the insulating effect. Glass itself transmits heat and cold very easily. The glass filling improves the thermal transmittance and improves the U-factor.
In the public area and with office buildings an additional façade from insulating glass elements is often suspended in front of the actual glass façades.
Its primary function is the sound protection, for example, near airports. When coated accordingly, insulating glass also protects against the sun.
Ion coloring for glass: Unchangeable
Coloring glass is a science in itself as so many factors come into it. The primary concern is the intended use of the finished product. Experts differentiate between two essential types of glass coloring: ion coloring and striking.
While the striking process can be controlled, a decision has to be made in advance for ion coloring, as this coloring takes place by adding relevant substances during glass production.
It gives the glass a specific and clearly definable color which can no longer be changed. These substances are called metal oxides. The right substance and combination give glass the desired color.
The complementary process for ion coloring of glass would be the decolorizing of glass. Specialists also use metal oxides for this. The experts use tables to determine which substance will create which color effect during ion coloring of glass.
By the way: In striking, the color only appears during the process – during subsequent heating of the glass or annealing.
Laboratory glass – robust and resistant.
What are the requirements for laboratory glass? What type of glass is that, anyway? Well, laboratory glass can also be referred to as hydrolytic glass, as the requirements are similar. Laboratory glass is produced especially for the requirements in chemistry, physics and/or biology laboratories.
Laboratory glass should have the following properties:
Resistance to heat and cold – to withstand the rapid changes between very high and very low temperatures. Impact resistance – very important, as laboratories tend to work with harmful substances.
Chemical resistance – the property of not reacting with acids, lyes or their reaction with water. The glass has to act absolutely neutral. Experts speak of hydrolytic glass and differentiate between different categories.
Laboratory glass is available as flat glass or already in the required shape. This glass is used, among other areas, in the petrochemicals industry, the food processing industry, the biotech industry, in medicine and in research institutes.
Laminated glass: Becoming one…
Laminated glass consists of at least two single layers joined into one glass sheet or plate via an adhesive intermediate layer. This intermediate layer may hereby consist of cast resin or a special thermoplastic film.
Laminated glass is normally based on pre-stressed glass but also single-layer safety glass. Glass doors, dividers from glass, sound protection elements, fire protection panes … these all represent uses for laminated glass.
Designer stairwell steps are also made from laminated glass. And what’s more: Did you know that the armored glass panels of security vehicles are made of laminated glass? Laminated glass is considered to be burglary-proof especially in the windows area, because it is hard to break.
However, not only simple elements with special physical properties can be manufactured with laminated glass. Laminated glass is ideally suited for artistic designs, using either laser technology or pressure bonding method.
Just imagine the effect of a semitransparent motif on the inside layer. Hardly any limits are imposed on the fantasy and the options of processing.
Laser: The solution for many tasks
The industrial future probably belongs to the laser. This is probably true as well for many other areas, such as the medical field or military applications. What actually does laser stand for?
Well, the term is a special acronym for Light Amplification by Stimulated Emission of Radiation. This refers both to the effect that is, the laser beam, and the machine that generates the laser beam.
The laser beam itself is actually made up of strongly bundled and high-intensity electromagnetic waves. Lasers can be found in many areas. You are probably familiar with laser pointers.
This is a rather harmless laser and its beam normally does not present any danger to people.
In this regard: Lasers are divided into classes depending on their power rating and hazard potential. Experts talk about laser classes.
The laser beam source: A “laser beam” travels
Put simply, the point where energy becomes a laser beam is referred to as the laser beam source. Experts refer to a resonator. The term is derived from the word “resonance”.
This resonator determines the intensity of a laser pulse or laser beam. With the so-called CO2 lasers this is normally a stationary laser beam source compared to the lens assembly that bundles the laser beam.
Experts refer to this as the “flying lens assembly”, that is movable. The different types of lasers of the respective applications require laser beam sources with different designs. There is a relatively new development in the area of communications.
Laser beams as carrier can transport large amounts of data, and that over a much greater distance than microwave rays are able to.
The development of flexible laser beam sources will play a key role in the future especially in the area of satellite communication.
Classification of lasers indicates power rating
Largely simplified, lasers are bundled, focused and very intensive light. Depending on their power rating, they are divided into laser classes and furnished with the appropriate warnings, because: From a certain class, only certified experts may operate the laser and: So-called laser commissioners must certify the device and/or the machine.
A laser is classified, for example, according to EN 60825-1. The hazard potential of a laser depends on the thickness of its enclosure. Lasers of class 1, for example, are considered harmless for eye and skin.
A class 2 laser develops a light intensity in the visible spectral range, that is, it is harmless for eyes and skin for very brief radiation periods. Class 3 and 4 lasers, on the other hand, are quite hazardous for humans.
The following applies in principal: Lasers must never be directed to persons, regardless of the class of the respective laser. By the way: Already the lasers of a DVD burner belong to class 3 and are therefore quite dangerous for persons.
Laser class IV: Maximum output and danger to life
Lasers of class 4 belong to the maximum output devices and/or machines. Its radiation is so intensive that any contact with parts of the human body, especially skin and eyes, causes serious injuries.
A class 4 laser may not be operated without suitable safety precautions, but by exception it is also approved for private use. The danger of a class 4 laser not only comes from the direct contact with the beam.
Diffusely dispersed laser light of a laser of this class is also hazardous to people. Appropriate fire and explosion protection measures must be taken when installing a laser of class 4. Maximum output lasers are primarily used in the industrial area, for example, for glass processing.
Laser cutting – effective, delicate and gentle on the material
Laser cutting has evolved into a proven process in the industry in recent years. Whether metal, glass or other materials: High-performance lasers can cut the most delicate structures and solids while being as gentle on the material as possible.
The process generally uses CO2 lasers which have been established in the industrial sector for a long time and are economically viable even for smaller product runs. They are often integrated into so-called multifunctional work stations.
These can cut as well as punch, weld, fold, drill and polish – in sequential work steps, monitored by a computer.
In some areas laser cutting is not ideal, as it leaves scorch marks, for example on metals, particularly on stainless steel. That is why stainless steel is usually cut with abrasive waterjet cutting.
Laser engraving systems – engravings for everyone.
Your own name, an award or a motto: There are many occasions that call for an engraving and just as many materials that can be engraved with a laser. Laser engraving systems are based on a CO2 laser from the category of gas lasers.
These devices are not only extremely effective, they are also very versatile. Depending on the specification, they can be used to create very delicate engravings, even by laymen, as the systems are fully computer controlled.
Of course there are differences between the individual systems, and of course there are small mobile systems as well as very powerful stationary systems.
Among the materials which are suitable for laser engraving are rubber in different types and hardness’s, paper, cardboard, wood and other organic materials, plastic objects, plastic film or PU foam boards, leather and textile materials. Glass is also engraved with laser technology in the industrial sector and in the artisan sector.
Laser lamella:
Optical illusion with practical effect
Would you have though that laser lamella can provide shade? No? It is difficult to imagine but basically absolutely possible.
The magic word is laser lamella. The process works just like subsurface engraving or subsurface structuring in glass.
The laser beam melts the glass inside at a point. This method can be used to introduce horizontal lamella into a glass sheet or glass elements for a curtained façade.
If direct sunlight shines on the lamella, it is reflected and dispersed. The effect is diffuse and dispersed sunlight in the room also called “light guiding”. In this manner, laser lamella can also be used in a way to provide shade for homes.
Laser machines: Effective and state-of-the-art automation
Laser technology is meanwhile used for many production processes. Just think about the automotive industry, glass-processing industry or the metal industry.
But laser technology can be encountered increasingly often in the medical field. Did you know that carries no longer needs to be removed with a classic drill?
Laser can already be used for this procedure. We are talking about laser machines here, though, and they are usually found in the industrial sector.
They are used for cutting glass, metal and other solid materials. They are employed for welding elements. Laser machines drill, mill, strip the surface of a body, introduce structures inside glass and so on.
There are different manufacturers of laser machines. Many of them have specialised in a certain method or task. However, the trend certainly moves to the laser machines that can handle different processes.
Laser pixel – a term from printing and beauty technology
The term “laser pixel” does not mean anything else but a “laser spot”. It is found, for example, in the field of cosmetic surgery and also in printing technology but here actually as so-called laser spot, the laser pixel.
The diameter of a laser spot determines the density value gain, that is, the color intensity. It is brought in relation to the grid element. These are exposure elements that can be accessed individually, in short REL.
An REL normally corresponds to the diameter of a laser spot or laser pixel. Experts in printing technology speak about grids when referring to the ink density, accuracy and thus quality of a print object. A laser pixel usually has a diameter from 0.01 to 0.03 mm.
Laser pixels can work quite some miracles in the medical sector. Of course, it is rather the laser beams that produce these miracles. In the area of cosmetic surgery, they can treat acne, skin irregularities, burst small vessels, hardening, callused skin, small wrinkles and other blemishes basically removing them.
Ageing spots, freckles and birth marks can also be removed by laser. The respective providers use the term laser pixels in this area, although it is rather misleading here.
Laser process: Hi-Tech in action.
The header already indicates what the term “laser process” means. It is the phase of a work process where the laser as such meets its task.
This sounds rather generally and it actually is: Any work process with a laser finally is a laser process, the method by which the laser processes the solid body at this moment. Let’s describe a laser process using the example of laser coating.
The principle is actually quite simple: An object shall be permanently protected, for example, against corrosion or aggressive substances. The most effective method is probably to furnish the object with a special alloy.
This is where the laser comes into play. Because alloying does not mean anything else then blending two substances. During the laser process the basic material, that is, the material to be processed, is partially melted and mixed with the desired supplementing material.
Both enter into a strong compound finally making the product more rugged and less susceptible, for example, against acids and corrosion. This sounds as if the entire solid body to be processed is partially melted; however, this is only a laser process on the surface.
Laser rangefinders – precise to a micrometer.
They are often encountered in unexpected places: police “laser speed guns”. The officers use them to determine the speed of a car based on the time the laser beam needs to travel from the object back to the origin.
These devices are actually simple laser rangefinders. They are also suitable for measuring rooms, even very narrow spaces. But they are also suitable for measuring or mapping out large, wide areas.
The reference value for measuring speed with the laser gun is the speed of light, as this is the speed at which the laser light travels. Experts call this method “time of flight”. Two other measuring methods are the light section method and triangulation.
The latter refers to measuring terrain. By the way: When the police measures the speed of a car with a laser gun, it is usually an absolute measurement.
This works up to a distance of 200 meters between measuring device and target object. A trap that no speed demon can escape.
The laser-resistant special felt protects the workpiece
This is a special feature of a laser-equipped glass processing machine. It is a fully automated machine for subsurface engraving of glass.
Because of its properties, it is able to engrave large quantities in a short amount of time. Experts refer to the industrial scale.
The workpiece to be processed, in this case always glass, lies on the so-called machine table, a movable support for the building elements. The problem: Glass is sensitive and can be easily scratched.
To prevent this, the machine table is equipped with a special liner which shall make sure, at the same time, that the glass cannot slide. This is a laser-resistant special felt. The work table itself is made from aluminum.
Laser spectroscopy – examinations with laser light
Scientists always want to know every little detail. That is why they study correlations, compositions, reactions and their consequences, and so on. Laser spectroscopy helps them with this.
This is a physical method using laser light as a physical medium to examine substances, or matter. In short: They screen matter to determine how the matter interacts with the laser or reacts to it.
Surely you are asking yourself – what is the point? Could we not just leave the matter alone? It is not normally screened by laser light, so why do we need to know how it reacts?
Let us take a look at medicine. Laser spectroscopy has been used actively in that field for many years, practically daily, to make really tiny objects, e.g. tissue, visible.
Laser spectroscopy is based on the principle of fluorescence spectroscopy. It uses the ability of matter to absorb light and emit it again in another form.
Another aspect is important for doctors and scientists: The processes in the human body, for example in muscle tissue, happen so unbelievably fast that they could not be seen and therefore not be understood without the use of laser spectroscopy. So we would miss out on crucial knowledge which is needed to establish certain connections.
Engraving by laser stripping
The term laser stripping does not mean anything else but the layer by layer removal of the surface of a component. Experts refer to this also as laser ablation. This technique can be used, for example, to introduce engraving and texts into glass or other solid bodies.
But there is more: Structures are also introduced into solids via laser stripping. Did you know that even the profile of the soles of your shoes may have been generated in the material by a laser?
Even a complicated 3D geometry can be “burned” into a solid body with a laser. The advantage: Lasers work exactly to the point and preserve the vicinity of the location to be processed. The market offers a series of special machines for laser stripping of different building materials.
Laser-structured glass plates: Art meets hi-tech
Glass can be structured in different ways. However, laser structuring is the most effective and by far most result-focused and thus flexible method in use.
Actually, structuring would need to be called matting of the glass surfaces, not over the whole but partial areas. While conventional methods have their difficulties with creating clear contours and visual 3D effects, laser technology has some clear advantages here.
Extraordinary effects, both over large and small areas, can be created, from very detailed and exact and architecturally correct to abstract and freely artistic. Laser-structured glass plates always draw attention with practical benefit one does not even really want to focus on when beholding the glass plates.
The worldwide active company Cerion is known for the development of highly specialised laser machines and offers the right solutions, for miniature and large formats, also for laser-structure glass plates.
Laser technology: More than half a century old.
Whatever Hollywood comes up with or the crazy futuristic ideas it produces on the screen becomes reality one day, say many science fiction fans… and they may be right in various areas.
Well, we will not begin to travel tomorrow with the spaceship Enterprise from galaxy to galaxy but: We do have laser technology. At one time, for example, it actually appeared as dangerous ray weapon in the cinemas or living rooms.
We are not sure whether Hollywood has pirated this idea from the scientists or vice versa. However, everyday life without laser technology is no longer conceivable.
The well-equipped dentist cleans dental root canals with a laser. The beauty apostle uses laser technology to create a more beautiful and younger skin.
Soon “old” is no longer a visible state but only a fact on paper. Even hair can be transplanted using laser technology. Will complete body parts be created from scratch some day per laser?
In the industrial realm, laser technology has been integrated in the production processes for quite some time as an effective and economically very interesting miracle tool. The technology is at the same time even highly precise and multifunctional. Laser technology is meanwhile used even in the communication field.
Laser therapy – the power of light
Now here is an example why laser spectroscopy is such an important component of medicine. For without examining the interactions of matter with the laser there would be no laser therapy.
How tissue reacts to the light and the wavelength of the laser is crucial to the success of laser treatment or laser therapy. There are now options for using this technology in virtually all areas of medicine.
Let us take a trip to the dentist: Who likes to go to the dentist, really? Well, maybe your dentist already work with laser technology. Then they can also use it to remove cavities.
As laser light is pulsed and these impulses are extremely short, our human nerves cannot detect them. That means: They are unable to send a signal to the brain indicating pain. Sometimes we humans can be pretty slow.
But dentistry is not the only area where laser therapy is used. Lasers are used for skin conditions and laser light can correct problems in underlying tissue. Laser therapy is offered in the field of cosmetics and by non-medical practitioners.
The background is always the interaction of laser light, wavelength and tissue. A few more areas where laser therapy is popular: eye surgery, tumour surgery, removal of gall stones, pigmentation, treatment of visible blood vessels, scars, warts, laser acupuncture, laser therapy against joint pain, and so on.
Laser types – a special laser for each purpose.
Lasers are part of everyday life. Just think about the printers which can be found in virtually all companies and most private households. If it is not an inkjet printer, a laser printer will be at work.
These use argon ion lasers. These types of laser can also be found in medical technology. They are gas lasers.
Experts differentiate the following laser types: semiconductor diode lasers, solid state lasers, gas lasers and dye lasers, with a basic differentiation between continuous wave and pulse.
Laser types from the semiconductor diode laser group can be found in the little pointers used by some lecturers. These contain a low power diode laser. Scanner units which read the bar codes on products also work with one of these laser types.
Gas lasers are probably the most common type. Devices with this laser type are used for processing and machining different materials. CO2 lasers are particularly well known and very powerful.
They can be found in the metal industry as well as in glass processing and finishing. These laser devices are often integrated into large machining centers.
Such machines combine the different work processes, increasing the economic efficiency of a company. Solid state lasers are primarily used in metrology and medical technology. These laser types generally work with precious stones which are used as an active medium.
Laser welding: Fast and precise.
Welding always produces weld seams. These are usually clearly visible beads which have to be reworked when the workpiece has cooled down. That is not very economically viable and not in keeping with our age of efficiency.
Laser welding is the alternative. This process has been used in the automotive industry for a long time as the weld seams are hardly visible and long reworking times are omitted.
Experts differentiate between spot welding and seam welding as well as laser soldering. The principle is the same as for welding, but with the use of an additive capable of joining substances that would normally not fuse.
A clear advantage of laser welding is, on the one hand, the speed coupled with the enormous precision of the work. On the other hand, the respective areas of the workpieces only heat up slightly.
Laser welding – or in this case bonding – can also join plastics. One very simple example is the sealing of plastic packaging.
Lead glass: Almost as pretty as a gemstone.
Do you have a diamond or a precious stone in your ring, earring or necklace? Are you sure? For rather than a precious stone it might be a replacement, such as lead glass or lead crystal glass. These are actually almost as beautiful as real precious stones.
But not to worry: Lead crystal glass is primarily used in the optical industry, in nuclear medicine or in radiology because of its good radiation shielding properties. This is due to the lead content in the glass, which is not harmful, by the way, as glass does not give off any fumes.
Lead crystal glass shines like a precious stone, it is very solid and experts attribute it with a good sound. Lead crystal glass is used for elegant vases and other receptacles.
This type of glass is also a popular material for the processing industry where glass is treated with sophisticated lasers without actually damaging it.
Light: Life-giving rays
When people did not know yet from where our light originates and what light actually is, they simply assumed that the light that can brighten a room comes from our eyes. Light was thereby not perceived as light beam but simply as brightness.
It was light and once came from the eyes scanning their environment with these rays. As a logical consequence, this viewing process existed only in the daytime, that is, at certain times.
Today we know: Light is the part of electromagnetic rays visible to our eyes and that at a wavelength between 380 and 780 nm. What people like to refer to as light without actually being light are the infra-red spectra and ultraviolet radiation.
If light is now bundled very strongly and furnished with some additional properties, it is generally referred to as laser beam, that is, bundled light. This is basically correct, although laser technology is based on highly complex physical processes.
Let’s close with an interesting questions: How fast is light? Well, light travels 299,792 kilometers per second. Can you copy that?
Medical lasers – gentle helpers
Lasers are precision tools – they work effectively and quickly and they are gentle on the material. These are ideal preconditions for using this technology in medicine. Medical lasers have actually long been routine tools in medical applications.
For example: Did you know that a laser can replace a scalpel? Medical lasers are also used in ophthalmology, for surgeries behind the eye. Dermatologists use medical lasers to treat skin conditions, warts, pigmentation problems and scars.
Medical lasers are also used for hair removal. It basically destroys the hair follicles. Ear, nose and throat medicine is another area where medical lasers have become popular.
It is used for removing tonsils and for treating tumors in the mouth and throat area. Medical lasers are even used for vocal cord surgeries.
Dentists do not use lasers for cosmetic surgery but to remove cavities with less pain. The laser impulses are so short that our nerves have no time to react.
And what’s more: In cancer therapy, medical lasers play an equally important role today.
Melt to fuse.
Glass is a mixture of different minerals, mostly quartz. So far, so good. But how can these components be transformed into a delicate material such as glass? This is achieved by melting. Experts call this “melting the batch”.
In practical application, this works as follows: The melting furnace heats the raw material to a temperature of around 1,200 degrees Celsius. That is the temperature where the components of the raw material – the batch – such as silicon dioxide, sodium oxide and/or calcium oxide merge or rather mix to form a unit. They become a glass mass.
The term “melting the batch” is not only used for glassmaking, though. Experts use generally use this term to describe the process where a mixture of different components is melted to form a unit. One possible example is the production of acrylic glass.
Metallic gas – medium for gas lasers
Metallic gas is actually nothing other than a laser medium. Neon gas, for example, is a metallic gas, just as helium and hydrogen. These gases are found in the highest concentration on Jupiter.
Hard to believe, but due to the atmospheric conditions there, they change directly from a gas state to a liquid state. And that means: On Jupiter, it is practically raining metallic gas.
Down here on earth, metallic gas is used in helium neon lasers, for example. These laser types are especially used for holography.
Although they have now been mostly replaced by other devices, they also used to be integrated in bar code scanner units for tills and in laser printers. One form of metallic gas is metallic hydrogen. That is actually only the specification for hydrogen under high pressure.
Mirror coats – reflection and mirror image
You look into the mirror at home and see yourself crisp and clear, sometimes too clear because this mirror reveals any wrinkle. You may prefer a mirror that does not reflect things quite so exactly.
Well, not a problem, because mirrors are only as good as the material used. An ordinary mirror consists of a flat glass plate – at any rate, a transparent medium, and a thin metallic mirror coat applied to the back of the glass.
Aluminum, gold or silver, often also combinations of those, are often used for these mirror coats. Applied means here applied with vapor.
These mirror coats can also be removed precisely via laser beam and interesting décor can be applied on the back of the mirror;
light can also shine through them. Mirror coats play a major role also in laser technology.
Glasses with respectively designed mirror coats deflect the laser beam and focus it on the desired target. The requirements on these mirror coats are naturally much more complex than those on a wardrobe mirror.
Both, the mirror medium and the mirror coat must be able to resist the laser beam and be resistant against temperature fluctuations.
Nitrogen laser – the power beam.
One laser powering another laser. Does that work? In science, the strong laser impulses of nitrogen lasers are used for powering a dye laser. Experts refer to this as “pumping”.
Nitrogen lasers work in the ultraviolet range and are generally used for scientific purposes. Nitrogen lasers work without resonators and therefore without mirrors. The reason: The impulses of the laser are simply too short.
Even the generated light would take too long to be reflected and use the atoms. This usually happens to optimize the energy performance of a laser. That is not the case here.
And that is why nitrogen lasers which work without a resonator are also called super beams. The laser source and the laser medium have to produce the power without an “amplifier”.
Optically excited lasers – solid state lasers
They drill, cut, solder and weld, they engrave, clean and harden. We are talking about optically excited lasers – solid state lasers – where the active laser medium is crystalline.
In addition to gas lasers, which are the most prevalent carbon dioxide lasers, they are the most powerful laser types which are commercially available. These lasers can be used on materials such as glass, metal and plastic.
The solid state lasers – the optically excited lasers – are driven or “pumped” by light or infrared radiation. “Optically excited” actually means: to excite through radiation.
Optically excited lasers require a resonator, unless they are fibre lasers. As in other laser types, this consists of two mirrors between which the laser medium is placed. One mirror is a 100 per cent mirror, letting nothing through, while the other mirror is partially transparent.
Optical fibres – charming effects
Surely you know these delicate filaments which are gathered like a fan, opening up like a flower at the top, with the ends lighting up prettily. These are optical fibres. They guide the generated light over short or long distances like through a channel, only releasing it again at the end. Generally these optical fibres are glass fibres. And these are also used for high speed data transfer.
Experts also refer to these fibres as light guide cables. The special characteristic here: The light basically remains inside the cable, it does not escape through the side walls. It actually is a kind of reflection within the optical fibre.
Of course there are different types of optical fibres, also made from polycarbonate and other substances which are similar to glass fibre. These fibres can be used to achieve charming effects. But they are also used very plainly as background lighting for displays.
Optical glass: To help us see better.
Would you have known this? Optical glass does not mean that we can see it, that is, visible glass. The term describes glass from which we optical components can be manufactured. These components included, for example, lenses, mirrors and prisms.
These items can be found in the lenses of cameras, binoculars, telescopes and microscopes. So-called overhead projectors also feature such optical components. Even the glass of your spectacles may fall into the category of optical glass. Principally, optical glass does not necessarily need to be different from conventional window glass.
Nonetheless, special requirements are placed on these components. Chemical ingredients are mixed into optical glass exactly for this reason, that is, to improve the properties of the future component and/or optimize it.
Experts speak of more than 250 different optical glasses. Most of them are based on crown glass or flint glass. The name Schott-Glas must be absolutely mentioned in the context of optical glass.
Optical resonators – in resonance with what?
One does not have to be a linguist to answer the following question correctly: Where does the term “resonator” come from? Correct: resonance. And indeed the word “resonator” refers to exactly that, in music as well as in laser technology. An optical resonator, also called an optical cavity, is a component of a solid state laser.
It is simply an assembly consisting of two mirrors – one high reflector and one output coupler. While the high reflector reflects 100 per cent of the radiation, the output coupler has to be partially transparent.
Metal mirrors would not be able to withstand the radiation load and simply produce excess losses.
Optical resonators are found in all solid state lasers as an essential component. For example in metal processing and machining:
The lasers are used for cutting, welding, engraving, drilling, tempering, cleaning and soldering … Solid state lasers are true all-round talents. This would not be possible without optical resonators.
Organic ink coats – glass finishing.
Imprinting glass surfaces also belongs to the area of glass finishing. Experts distinguish between the thermoplastic ceramic inks and organic inks.
While the thermoplastic ceramic inks are heated to 80 °C and then applied to the glass body, where they solidify immediately, organic ink coats are applied at ambient temperatures, that is, without additional heating. Each ink is applied separately.
The respective ink coat is exposed to UV radiation between the individual passes. The ink dries within seconds.
With so-called direct screen printing, any number of ink coats can be applied to the glass body in this manner. By the way, organic ink coats can be removed again from the glass layer by layer via laser stripping, without residues and damage to the glass surface.
Particle filters: Not only important in the automotive area.
When the term “particle filter” is mentioned, one thinks immediately to the automotive industry, exhaust gas standards and soot particle filters. Their task is to catch even minute contaminations, that is, fine dust, from the exhaust gases of a vehicle before they enter the environment.
Especially fine dust is a serious problem for the human respiratory organs. They do not only cause allergies but are brought into context with much more serious diseases.
Particle filters are therefore used to clean the exhaust gases of automobiles thus reducing pollution for people – not without critique but still effective.
However, particle filters are also used in laser technology. These filters are referred to here as deionization filters. They clean the air in the cooling circuit of the laser and must be regularly replaced if the laser shall function without problems in the long run.
PET: Not only the material from which our bottles are made.
PET, polyethylene terephthalate, quite a tongue-breaker, is a thermoplastic plastic and belongs to the group of the polyesters. We all know PET from everyday life. Just think of the disposable beverage bottles from plastic. They are disposable PET bottles.
We encounter PET also in the textile industry, that is, as additive to textile fibres. This plastic is also available on rolls as pure PET film. PET is considered stable and easy to use; properties that make it nearly indispensable nowadays.
However, the substance also has its dark sides because especially the beverage bottles from PET are suspected to releasing harmful substances into the liquid they contain. Various disorders in the human body are brought in connection with the effect of the PET bottles.
The term PET is also found in medicine as abbreviation for Positron Emissions Tomography. This is a method in nuclear medicine used to produce sectional images from live organs (organisms).
Glass, and yet no glass: PMMA
What is acrylic glass or also Plexiglas®? Because we put the question here, the answer can only be PMMA plastic, that is, polymethylmethacrylate. Although this is not glass, the product is called acrylic glass, because it has similar properties.
Acrylic glass is either poured as so-called GS glass or extruded. It is then called XT. GS is considered here to be more stable and impact-proof.
PMMA is found, for example, as sheets – glass substitute -, in the form of the early contact lenses and in many other areas. Because this material has similar properties as glass, PMMA can also be processed and finished with laser technology.
Polyamide: A tough material
Are you familiar with Dederon? This is a brand name from the former GDR. It represented a synthetic fibre, the polyamide fibre. For example, lab coats or shopping bags were made of Dederon. Perlon, the deutschGerman counterpart to Nylon, is another term for such a polyamide fibre.
As you know: The woman wore Nylon, sorry, Perlon in Germany. But what is this material with so many names, polyamide, or what are polyamides? They are synthetic thermoplastic plastics for technical use.
Polyamide is then a term for different polyamides. Experts appreciate their strength, but fear their susceptibility against acids and so-called oxidising chemicals.
Polycarbonate: Revolutionary invention
The scene is not pleasant but shows once more how rugged the material is we want to present to you here: In the 80ies there were occasional clashes between the police and vandalizing protesters.
Of course, we still have such clashes, but only between hooligans and the police. The officers then carry a protective shield, highly impact-resistant, dimensionally stable and rugged. These shields are made from polycarbonate, in brief PC.
We find PC not only with the police equipment, however, Machine protective hoods and covers may consist of polycarbonate.
Laser machines or laser-assisted glass processing centers are an example. Vehicle glazing may also consist of PC and the visors of motorcycle helmets are made from it.
PC has glass-like structures and therefore belongs to the amorphous substances. This also means: It can be structured via laser beam. Other product examples for PC are: Canopies, balcony railing, sound protection elements and panels for devices.
Preparing the batch: The formulation determines the result.
It is just like in normal life. To bake bread, you have to prepare dough. Basically you are preparing a batch. This batch later turns into the load of bread.
In the end, the recipe determines which ingredients go into the bread dough batch at which ratio and how the bread turns out in the end. Well, a little skill and the right baking time and temperature are also involved. All this also applies to “preparing” glass.
In this case, the batch consists of mineral substances. It is important which additives are added. During glass production of course this all takes place in enormous dimensions:
The raw materials are delivered to the production facility in large silo vehicles. There they are transferred into large storage containers which are also called silos. Then they are portioned with scales and fed into a mixer.
It is a little bit like a cement mixer at a construction site. But glass production certainly does not call for adding rough amounts of ingredients. This is all controlled by computers.
The mixer ensures even distribution of all ingredients within the batch. When the batch leaves the mixer via a conveyor or bucket, it is ready for the oven.
Quartz glass: The glass for special applications
Quartz glass is also translated as silica glass. One could therefore refer to glass from rock. And indeed: Quartz glass can be won when melting quartz (sand) and allowing it to harden. Contrary to other glasses, quartz glass is considered absolutely pure glass; it does not contain any additives.
In the chemical area it is marked by its superb resistance against acids. It is considered as having extreme puncture resistance and is particularly suitable for insulating purposes for electrical components.
As a logical consequence, quartz glass is also found quite often in the following application areas:
In hot environments as measuring or sight glass, for example, in engines and furnaces. However, quartz glass is also used in the area of laser technology.
As insulating layer in the area of semiconductor production.
In the area of ultraviolet optics.
A bulb for halogen lamps
Did you know that the windows of the U.S. space shuttles were made of quartz glass? The base material for quartz glass, that is, quartz sand, is also sold in bags to private households.
Quartz is a natural product, perfect for sanding slippery roadways and walks, providing a good grip to the human foot.
Rod lasers – an old term for a true specialist
The term “rod laser” is hardly used these days. It only describes the design of the laser and defines the laser medium which consists of a rod-shaped crystal.
Rod lasers are available with different power levels, depending on the crystal as a medium. Simply put: the bigger, the more powerful.
Rod lasers are still in use. Pulsed rod lasers, for example, can be used for fine welding tasks or fine cutting tasks.
The technical terms for these processes are laser welding and laser cutting. Disadvantage of rod lasers: They require good cooling via correspondingly massive heat sinks. This in turn, experts say, reduces their performance.
Safety glass: Pre-stressed lasts longer.
When very high requirements are put on glass sheets, the so-called safety glass is often the only answer. Experts differentiate between the single-layer safety glass (ESG) and laminated glass (VSG).
Safety glass is principally so-called “pre-stressed glass”. This glass was melted at maximum temperatures and then cooled suddenly. With this process, tensile stress develops in the core of the glass and compression stress on the surface.
Safety glass is marked both by its impact-resistance and its resistance against large and abrupt temperature changes. Because of its “pre-stressed” properties, safety glass shatters into crumbs with dull edges in case of emergency.
Semiconductor laser: Small and handy.
Have you ever given a lecture or listened to one? Probably the latter. For giving a speech it is not everyone’s thing. Why are we asking this question?
Well, if the lecturer wants to move about freely and not stick to their laptop, they need a tool for pointing out certain items on the large screen or display. Right. That is a pointer. Or more correctly a laser pointer the light of which should not enter your eyes.
And this laser pointer is nothing other than a semiconductor laser, also referred to as a laser diode. It is a semiconductor component that is related to the famous LEDs but with the capability of producing laser light. Experts already worked on the development of this technology in the 1960s.
In everyday life, these semiconductor lasers can also be found in optical measuring devices. Light barriers are based on this principle, bar code scanners also work with a semiconductor laser and even laser printers have one of these units.
Shaping glass: It is the method that counts
Glass as an amorphous solid can be formed into virtually any shape. What matters is, on the one hand, the actual state of the glass and, on the other hand, the method used for shaping the glass.
The basic technologies for glass are rolling, pressing, centrifuging, blowing and spinning as well as drawing. While artisan shaping is often still done manually by glass blowers, machines are taking over this task in the course of industrial glass processing and finishing. Modern laser technology is also used for shaping glass.
The selected shaping method depends on the glass and its intended use. Sheet glass is usually produced with the so-called float glass process, where the liquid glass is brought into a flat shape and cooled down gradually. Sheet glass can also be rolled or drawn.
It is also known as float glass – a perfect material for further processing using state-of-the-art laser technology. By the way: Glass can even be spun. Yes, you read correctly. That is how fine glass fibres are made.
Silicon dioxide – pure quartz glass
Silicone dioxide, also known as silica, in its pure form is actually quartz glass or fused quartz. But SIO2, as silicone dioxide is referred to in chemical terms, can be found in unexpected places and products of everyday life.
As a rule, SIO2 is harmless for people. One version of it can therefore also be found in many medicines. Beyond that, silicone dioxide can be found in paints and varnishes or in adhesives.
Silicone dioxide is also involved in the coating of certain types of paper. The greatest significance of the substance, however, is as a component of glass, which in its purest form is fused quartz. And that has several positive properties.
Fused quartz is particularly resistant to chemicals and is not corroded by any acids, except for hydrofluoric acid. It is resistant to large temperature fluctuations and offers great impact resistance. Silicone dioxide is resistant to a variety of weather influences so it does not corrode easily.
Single laser: Laser show and medicine
One would think that a single laser is nearly self-explanatory. Indeed, this is a laser with little power but superb quality. Single lasers are used, for example, in the medical field such as with dentistry and dermatology.
If you have an eczema on the skin or suffer from acne or other skin problems, the single laser may possibly help you. The specialist uses this laser to carefully remove diseased or damaged skin areas.
They abrade several layers while promoting the growth of new skin layers. Single lasers are also used with laser printers, as you know them from the home office, also with plotters, with holography, i.e. a form of three-dimensional presentation of bodies per laser.
Finally, we meet this single-beam laser in the show area. Glamorous laser shows are often produced by devices equipped with a single laser.
Soda lime glass – the most prevalent type of glass
Soda lime glass, also called soda lime silica glass, is probably the most prevalent type of glass overall. Most glass objects for practical use are made of this soda lime glass.
It begins with bottles and ends with laminated glass for vehicles. What is important in this context: The production process has nothing to do with the glass type in this case. It refers to the formula for the glass and its basic properties.
Soda lime glass does not tolerate great temperature differences. That means: Exposing the glass to strong temperature fluctuations creates enormous tensions. These eventually cause the glass to crack.
For this reason, soda lime glass is not used for laboratory work. From a mechanical point of view, soda lime glass has no special properties such as impact resistance.
These properties are achieved through special processes. To create a certain breaking resistance, glass needs pre-stressing, for example.
Solid state laser precision tool
When referring to solid state lasers then those units are meant that work with a crystalline or glass-type carrier medium, also called host medium.
Simplified, this medium, quite often consisting of glass, reinforces the laser beam. The advantage of glass as host medium lies in its unsophisticated manufacturing, entirely independent of the dimensions.
Next to the CO2, i.e. carbon dioxide laser, the solid state laser is most common in the industry. It is used, for example, as precision tool to cut different types of materials.
Drilling is also performed via solid state laser; in this case using pulsed operation. Additional tasks: Engraving and/or welding. Both, solid state lasers and CO2 lasers, have become an indispensable element in metal machining and processing.
Special glass tubing cutters for delicate tubes
Glass tubes are delicate tools which are also used in the area of laser technology. They can be cut with two methods:
with laser technology or with glass tubing cutters or special glass tubing cutters. These fix the glass tube and cut it with fine cutting wheels.
It is important to proceed carefully to avoid breaking the delicate glass inadvertently. The glass tube in the special glass tubing cutter is cut to the desired length in even movements.
In industrial applications, glass tubes are cut to size with laser technology – with computer controlled glass tubing cutters.
The spectral range defines the visibility of light. When we talk about the spectral range, we usually mean the light spectrum. This is differentiated into different wavelengths.
Depending on the wavelength, we refer to the visible spectral range of light and the spectral range of UV light, the portion of the electromagnetic spectrum which is not visible to the human eye.
We also refer to spectral ranges in laser technology, as lasers produce light beams. These light beams are not within the visible spectral range for all types. The evaluation of the performance of a laser also depends on the spectral range.
The light spectrum visible to the human eye includes all perceptible colors that we can differentiate. What is important here is that we do not need any aids or tools to cover this spectral range.
By the way: Naturally the human perception of the light spectrum has been scientifically standardized. Just making sure that everything is well regulated.
Striking colors: When glass gets hot and blushes.
Glass in its pure form is clear and transparent. Colors are created by chemical processes, after adding additives to the liquid glass and annealing the finished glass. Experts refer to this process as “striking”.
The glass takes on a color during the annealing process. Annealing is a heat treatment to bring the glass to a certain temperature. And this is how it works: First, the glass is melted. In this case, it remains colorless, though. The annealing process begins afterwards.
The glass changes color. Different colors develop depending on the intensity of the annealing or heating process. This is due to microscopically small chalcogenide crystals, usually with added cadmium. These increase or grow as the annealing process continues.
You could say that this process turns the amorphous structure of the glass into an ordered, crystalline structure. This process for coloring glass is called “striking”, a targeted change of the structure and therefore a targeted change in color. As a rule, glass with striking color has a very sharp color edge.
This makes it ideal for use as filter glass. It gets interesting when this glass is now processed with modern laser technology. This creates an exceptional color array.
Ink coats have no chance with laser stripping.
Wherever painting or coating is applied, stripping per laser technology is possible as well. In many situations, this is even the more precise, time-saving and thus economic approach.
Imagine a component from metal, steel, glass or other material shall remain only partially free from ink coats or coating. Experts would now explain that exactly this location must be covered, for example, taped off, with elaborate effort.
This process can now be dispensed with, because stripping per laser is much more effective and preserves the material much better. Layer by layer of the coating can now be carefully removed with the laser – if necessary, even down to the base material.
For example, if the primer is supposed to remain on the material, the laser can be adjusted accordingly. Stripping then takes basically place slice by slice.
Subsurface glass engraving: 3D effects on/in glass
Subsurface engraving is, so to speak, the freestyle sector of glass processing with laser technology. It is also referred to as subsurface laser engraving. Three-dimensional figures are, so to speak, introduced with it into the inside of the glass.
Experts speak of creating three-dimensional bodies portrayed inside a solid piece of material. However, the solid material into which a three-dimensional figure is introduced does not necessarily have to exist of glass.
Polycarbonate, sapphire or diamond are also suitable. The transparency of the body is important. With subsurface engraving in glass, the glass is actually damaged, that is melted, to a small degree at the focal point of the laser.
This subsurface “damage” appears as a white dot when exposed to light. Experts refer to this as optical refraction.
The integrity of the glass, that is, its surface tension, is not damaged through the internal damage. The result is greater permanence.
A continuous wave: The CW range
Do you know the meaning of the two letters CW in this context? No? That’s fine, as you have most likely had no contact with the concept of continuous waves before.
The term is used for radar systems, for example. Today it is much more common for high efficiency laser systems, though. The so-called CW range is simply the range inside whose parameters the laser can be adjusted, aligned and oriented.
So it describes a certain wavelength which can vary from laser to laser. As complicated as it sounds, it is actually very easy to explain. But we certainly would not expect you to know this. The CW range is rather something for laser technology experts or scientists.
TVG: Hard and insensitive glass.
The find the term TVG everywhere where enormous physical demands are placed on glass body and glass surfaces. It means nothing else as partially pre-stressed glass.
One could also say: hardened glass, because the special thermal treatment applied to this glass makes it very impact-resistant and especially insensitive against large temperature differences.
TVG is also considered safety glass and is used in most areas in the laminated glass version (VSG). This special glass is found as façade elements, not seldom processed with laser technology, as overhead glazing for canopies or railing elements.
TVG is often used as curtained glass façade in front of the actual façade of an office building. It is primarily used here as protection against noise and weather. Naturally, TVG can also be processed further via laser technology using appropriate machine.
YAG lasers – precision tools
YAG lasers are true precision tools. They are solid state lasers with a great range of applications. The standard tasks range from drilling very fine holes and cutting thin sheet meal to precise spot welding. But that is by far not everything. YAG lasers are also used to create high quality and durable engravings.
These tasks extend far into the field of quality assurance. But the lasers cannot just cut, drill, weld and engrave. These are tasks where the laser acts on the material, purposely “damaging” or changing it.
YAG lasers can also be used for materials testing in the infrared range. The material is not damaged by this process.
And what is more: In the field of medicine, YAG lasers are used as medical lasers for dentistry. And in cancer therapy, doctors fight lung metastases with this laser.
