Switchable glass is the biggest innovation to come to glass technology in over a century. Both smart glass and film go from clear to frosted when powered on and off. Now, glass can be installed with built-in privacy or you can apply smart film to the surface of existing glass, transforming it into smart glass. While switchable glass technology may seem like magic and the ideal solution, there are a few things you should know before purchasing smart glass or film.
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Watch this video and keep reading to better understand how smart PDLC glass works, its limitations and the value it offers beyond privacy.
When privacy glass is switched to clear, there can be a slight milkiness that we refer to as haze. This cannot be avoided because of the PDLC crystals that give the glass it&#;s switchable properties. These crystals act as tiny droplets that reflect the light and create some haze. Under normal lighting conditions, smart glass will look perfectly clear when powered on. Any haze will be most obvious under uneven lighting conditions and artificial light.
Fortunately, there are ways to minimize this haze. With a high quality product, this haze will barely be noticeable. Smart Glass Country&#;s products have a haze rating below 4 percent, which is the best on the market. Lower quality PDLC films may be hazier due to an uneven distribution of PDLC crystals throughout the film and cheap plastics. Any haze can be made less visible by optimizing lighting conditions.
Smart glass and film are not as cheap as buying a standard set of curtains. Smart glass costs $80-100 dollars per square foot and smart film costs $25-40 per square foot. While you may come across some PDLC films being sold at cheap prices overseas, this is usually for a reason. Many of these films are thinner, more prone to damage and difficult to install.
If you are considering privacy glass as an option for your windows, walls or doors it is helpful to consider it&#;s overall value, as smart glass offers many other benefits in addition to providing privacy. Our smart glass is laminated and tempered, comes with built-in soundproofing and minimizes heat gain.
Here is a breakdown of how much each of these features would cost if purchased separately:
Tempered glass = 10$/sqft
Laminated glass = $15 per sqft
Smart glass blocks 99% of UV light
Cost of UV protection= $12 per sqft
Smart glass blocks 73% of Infrared light
Cost of heat gain reduction treatment= $15 per sqft
Privacy glass includes built in soundproofing
Cost of sound reduction glass= $100 per sqft
Smart glass is as convenient as motorized blinds
Motorized blinds= $50 per sqft
It can also be used as a whiteboard or rear projection screen.
Whiteboard= $5 per sqft
Projection screen= $10 per sqft
10+15+12+15+100+50 +5+10=$217
The total value of all these features bought separately is $217 dollars per square foot.
High quality smart glass combines all these properties and costs 60 % less.
Smart film is not recommended for outdoor use, moisture prone areas and public spaces where vandalism is common. While our smart film is made with the best materials available, it still is an electric device and may become damaged if exposed to excessive moisture and should not be used outdoors. Privacy film can be used indoors in moisture prone areas and cleaned with liquids so long as the edges are covered with silicon to prevent damage.
The busbar area is the most delicate part of the film, as this is where the wires connect. If it is damaged the film will no longer switch from clear to frosted. So you should pay extra attention to this area and handle it with care.
Like any plastic, smart film can be scratched by dogs, cats or small children. If you are installing privacy film on a window or door that your pets or young children will constantly be in contact with, you will want to place a protective liner over top of the film to protect it from scratches.
We recommend purchasing smart glass for high traffic areas, public spaces and glass surfaces that are exposed to the outdoors. With smart glass, the PDLC film is sandwiched between two pieces of laminated and tempered safety glass, which protects it from damage. This is also why our warranty for our switchable glass is 3 years and our warranty for the switchable film is 1 year.
Some privacy films will slowly discolour as they are exposed to UV light and become yellowish. However, high quality window films will not yellow with the sun and will always look clear.
Low quality smart film can easily become delaminated. One factor that can lead to delamination is the peeling strength of the film. A high quality film will have a strong PDLC glue that keeps the layers of the film stuck together, lower quality films may have poor adhesives and peel apart- even when in storage.
Delamination can also occur during smart film installation. These common mistakes, such as trimming the film with a dull blade, can easily be avoided and we provide thorough installation instructions to ensure smart film is installed successfully.
Now you know the truth about privacy film and glass. For more information please explore our website or contact us and we will be happy to answer your questions and provide you with a free estimate.
If you want to learn more, please visit our website in pdlc glass.
What is a Liquid Crystal?
A &#;liquid crystal&#; is a thermodynamically stable &#;mesophase&#; of matter which resides in between the solid phase and the liquid phase.
Liquid crystals were first discovered in by Friedrich Reinitzer (-), an Austrian botanist, who was studying cholesterol in plants. He observed that the material known as cholesteryl benzoate had two melting points, with the first resulting in an initial &#;cloudy liquid state&#; and the second giving a &#;clear state&#;. The cloudy liquid state is what we now refer to as a liquid crystal.
Whereas solids are highly ordered, and liquids (and gases) have no such internal order, molecules of a liquid crystal lie somewhere in between. Liquid crystals contain rod or disc-shaped structures (called &#;mesogens&#;) which point along a common axis, called a &#;director&#;. They are easily polarisable (typically with an electric field).
If you want to know more about liquid crystals, check out our article at this link.
Why are liquid crystals sometimes dispersed in a polymer?
The polymer allows the liquid crystals to be mixed and cured into a film structure, which can then be sandwiched between panels of glass or plastic. The polymer has constant optical properties which do not vary across its structure, and hence is considered &#;isotropic&#;.
In contrast, the liquid crystal itself is &#;anisotropic&#;, since its optical characteristics are not constant across its structure, but rather can vary under application of an electric field.
Why is PDLC Glass considered &#;smart&#;?
The smartness of PDLC comes from its ability to refract light randomly (i.e. to scatter light), or to transmit light, depending on the electrical voltage applied to it. This is normally an alternating voltage (typically 36-110 Vac), which exerts an alternating electric field across the PDLC material.
We should remember that PDLC film or glass is only as smart as the &#;control system&#; which drives it. This can be a simple push button switch, a light sensor, or a digital building automation system.
How does PDLC smart glass work?
With no applied voltage, the liquid crystals are randomly oriented and scatter the light which enters. When a voltage is applied, the liquid crystals orient themselves parallel to each other, allowing light through.
Does PDLC smart glass become &#;opaque&#;?
No, the correct term is translucent, since light still gets through, albeit scattered in many directions. The glass would be &#;opaque&#; only if the light was blocked or absorbed.
There are however some PDLC products which mix dyes into the liquid crystals, thus giving a (permanent) dark colouration, and this can result in some of the light being blocked, giving an &#;opaque&#; result.
What are the applications for PDLC smart glass?
PDLC smart glass can be found in commercial and residential smart windows, consumer electronics and display cases for retail and museums, as well as in healthcare, hospitality and transportation.
Liquid crystals can also be found in high-resolution displays for near-eye wearables and as medical & industrial thermometers. See below for more examples.
Why does PDLC glass scatter light?
The liquid crystals change their refractive index in relation to the isotropically transparent polymer in which they are immersed, thereby creating multiple step boundaries throughout the PDLC.
It is this change in refractive index at each boundary which causes light to change course. Since the PDLC material contains millions of liquid crystals, each with a boundary facing a slightly different way, the light is scattered in many directions.
The net effect is to &#;hide&#; whatever is behind the PDLC smart glass.
What is the structure of PDLC glass?
(Images courtesy of Smartglass International)
PDLC smart glass is composed of :-
Inner panels of optically clear PET plastic (polyethylene terephthalate)
, sandwiched within:Does PDLC smart glass &#;conduct&#; electricity?
No, the internal PDLC layer is plastic and does not conduct electricity, since it is electrically insulative. Rather, it behaves as the internal dielectric layer of a capacitor, where the applied AC signal on the plates of &#;the capacitor&#; causes an alternating electric field throughout the PDLC film. This is what aligns the liquid crystals with the frequency of the signal (normally 50 Hz or 60 Hz).
How much light does PDLC glass transmit?
When not connected to a voltage, typically the transmittance can be as low as 2% if the material contains dyes, or up to 65% when the PDLC is not dyed.
When connected to a voltage, the transmittance can reach 70%-80%, but this value varies from manufacturer to manufacturer.
Are liquid crystals only available as artificial materials?
Not at all; common examples of natural occurrences of liquid crystals include proteins, soaps, detergents, and even some types of clay.
What are the major reasons for using PDLC smart glass?
Which sectors are using PDLC glass?
What form factors are PDLC glass available in?
Can the PDLC glass be dimmed?
Yes, the glass can be dimmed by varying the applied voltage from 0% in the OFF state up to the maximum transmittance (typically 70% or 80%). This is achieved by altering the voltage with a variable isolating transformer, or electronically with a switched-mode smart glass dimmer.
Where can I buy samples of PDLC smart film or glass?
You can buy cost-effective samples right here on Smartglass World, on our Samples page. Here are examples of PDLC smart film and PDLC smart glass available from our stock, ready to ship worldwide:
Where can I find companies to install PDLC smartglass in my home?
You can check out our Search page, where you can specify the type of technology, the role of the company (e.g. manufacturer, distributor, or installer) as well as the types of smartglass products you are looking for (e.g. smartglass windows, walls, skylights, etc).
You can also specify product characteristics, such as minimum visible light transmittance (VLT), desired operating voltage, or maximum power dissipation:
The results are produced after hitting the &#;Show Results&#; button:-
Want more information on laminated glass or tempered glass? Feel free to contact us.
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