Smart windows
Encyclopedia
Smart glass, EGlass, or switchable glass, also called smart windows or switchable windows in its application to window
s or skylights, refers to electrically switchable glass
or glazing which changes light transmission properties when voltage is applied.
Certain types of smart glass can allow users to control the amount of light
and heat
passing through: with the press of a button, it changes from transparent to translucent
, partially blocking light while maintaining a clear view of what lies behind the window. Another type of smart glass can provide privacy
at the turn of a switch.
Smart glass technologies include electrochromic devices, suspended particle devices, micro-blinds and liquid crystal devices.
The use of smart glass can save costs for heating, air-conditioning
and lighting
and avoid the cost of installing and maintaining motorized light screens or blind
s or curtain
s. When opaque, liquid crystal or electrochromic smart glass blocks most UV, thereby reducing fabric fading; for SPD-type smart glass, this is achieved when used in conjunction with low emissivity
coatings.
Critical aspects of smart glass include installation costs, the use of electricity, durability, as well as functional features such as the speed of control, possibilities for dimming, and the degree of transparency of the glass.
: it changes between a colored, translucent state (usually blue) and a transparent state. A burst of electricity is required for changing its opacity, but once the change has been effected, no electricity is needed for maintaining the particular shade which has been reached. Darkening occurs from the edges, moving inward, and is a slow process, ranging from many seconds to several minutes depending on window size. Electrochromic glass provides visibility even in the darkened state and thus preserves visible contact with the outside environment. It has been used in small-scale applications such as rearview mirrors. Electrochromic technology also finds use in indoor applications, for example, for protection of objects under the glass of museum display cases and picture frame glass from the damaging effects of the UV and visible wavelengths of artificial light.
Recent advances in electrochromic materials pertaining to transition-metal hydride electrochromics have led to the development of reflective hydrides, which become reflective rather than absorbing, and thus switch states between transparent and mirror-like.
Recent advancements in modified porous nano-crystalline films have enabled the creation of electrochromic display. The single substrate display structure consists of several stacked porous layers printed on top of each other on a substrate modified with a transparent conductor (such as ITO or PEDOT:PSS). Each printed layer has a specific set of functions. A working electrode consists of a positive porous semiconductor (say Titanium Dioxide, TiO2) with adsorbed chromogens (different chromogens for different colors). These chromogens change color by reduction or oxidation. A passivator is used as the negative of the image to improve electrical performance. The insulator layer serves the purpose of increasing the contrast ratio and separating the working electrode electrically from the counter electrode. The counter electrode provides a high capacitance to counterbalances the charge inserted/extracted on the SEG electrode (and maintain overall device charge neutrality). Carbon is an example of charge reservoir film. A conducting carbon layer is typically used as the conductive back contact for the counter electrode. In the last printing step, the porous monolith structure is overprinted with a liquid or polymer-gel electrolyte, dried, and then may be incorporated into various encapsulation or enclosures, depending on the application requirements. Displays are very thin, typically 30 micrometer, or about 1/3 of a human hair. The device can be switched on by applying a electrical potential to the transparent conducting substrate relative to the conductive carbon layer. This causes a reduction of viologen molecules (coloration) to occur inside the working electrode. By reversing the applied potential or providing a discharge path, the device bleaches. A unique feature of the electrochromic monolith is the relatively low voltage (around 1 Volt) needed to color or bleach the viologens. This can be explained by the small over- potentials needed to drive the electrochemical reduction of the surface adsorbed viologens/chromogens.
laminate
of rod-like particles suspended
in a fluid is placed between two glass or plastic layers, or attached to one layer. When no voltage is applied, the suspended particles are arranged in random orientations and tend to absorb light, so that the glass panel looks dark (or opaque), blue or, in more recent developments, grey or black colour. When voltage is applied, the suspended particles align and let light pass. SPDs can be manually or automatically “tuned” to precisely control the amount of light, glare and heat passing through, reducing the need for air conditioning during the summer months and heating during winter. Other advantages include reduction of buildings' carbon emissions and the elimination of a need for expensive window dressings.
devices (PDLCs), liquid crystals are dissolved or dispersed into a liquid polymer followed by solidification or curing of the polymer. During the change of the polymer from a liquid to solid, the liquid crystals become incompatible with the solid polymer and form droplets throughout the solid polymer. The curing conditions affect the size of the droplets that in turn affect the final operating properties of the "smart window". Typically, the liquid mix of polymer and liquid crystals is placed between two layers of glass or plastic that include a thin layer of a transparent, conductive material followed by curing of the polymer, thereby forming the basic sandwich structure of the smart window. This structure is in effect a capacitor.
Electrodes from a power supply are attached to the transparent electrodes. With no applied voltage, the liquid crystals are randomly arranged in the droplets, resulting in scattering of light as it passes through the smart window assembly. This results in the translucent, "milky white" appearance. When a voltage is applied to the electrodes, the electric field formed between the two transparent electrodes on the glass causes the liquid crystals to align, allowing light to pass through the droplets with very little scattering and resulting in a transparent state. The degree of transparency can be controlled by the applied voltage. This is possible because at lower voltages, only a few of the liquid crystals align completely in the electric field, so only a small portion of the light passes through while most of the light is scattered. As the voltage is increased, fewer liquid crystals remain out of alignment, resulting in less light being scattered. It is also possible to control the amount of light and heat passing through, when tints and special inner layers are used. It is also possible to create fire-rated and anti X-Ray versions for use in special applications. Most of the devices offered today operate in on or off states only, even though the technology to provide for variable levels of transparency is easily applied. This technology has been used in interior and exterior settings for privacy control (for example conference rooms, intensive-care areas, bathroom/shower doors) and as a temporary projection screen
.
MagicGlas™ panels use a lamination process which encapsulates a PDLC film between two or more glass sheets. By means of a minute electrical current, users can immediately switch the MagicGlas™ from clear to private (opaque) and vice versa. When the electrical supply is switched on, the liquid crystal molecules align, the panel instantly clears and light passes through. When the power is switched off the liquid crystal molecules are randomly oriented, scattering light, and the panel becomes opaque.
A video available on youtube describes briefly the micro-blinds.
These types of glazing cannot be controlled manually. In contrast, all electrically switched smart windows can be made to automatically adapt their light transmission properties in response to temperature or brightness by integration with a thermometer
or photosensor
, respectively
The topic of smart windows in a further sense includes LED Embedded Films which may be switched on at reduced light intensity. The process of laminating these LED embedded films between glass will allow the production of Transparent LED embedded glass
es. As most glass companies are not skilled in mounting LEDs (Light Emitting Diodes) onto metallized glass, the LEDs are located on a separate transparent conductive polymeric interlayer that may be laminated by any glass lamination unit.
Production technologies
Smart glass is produced by means of lamination of two or more glass or polycarbonate sheets.
Smart glass has found uses in the healthcare industry, where easily cleaned surfaces are essential and there are considerations of patient privacy. Smart glass products can replace traditional blind systems that are difficult to clean and can harbor dirt and bugs. Research has shown that patient comfort can help reduce recovery time.
One of the most popular Smart Glass applications is as projection screen
s.
Polyvision privacy glass by Polytron Technologies, Inc. was shown at the Shanghai Expo 2010. Five privacy glass panels formed a curved window that, together with the control console, resembled a professional wheel house.
Another example of use is the installation of PDLC-based smart glass, in the EDGE, a glass cube which protrudes out from the 88th floor skydeck of the world's highest residential tower, Eureka Towers, located in Melbourne. The cube can hold 13 people. When it extends out of the building by 3 metres, the glass is made transparent, giving the cube's occupants views of Melbourne from a height of 275 metres. The same type of smart glass has also been proposed for use in hospital settings to controllably provide patients with privacy as needed.
PDLC technology was used in a display to unveil the Nissan GTR at the Canadian International Auto Show in Toronto.
In the media, the updated set for the Seven Network
's Sunrise
program features a Smart Glass background that uses liquid crystal switchable glass (AGP UMU Glass) supplied by Architectural Glass Projects. The technology is especially suited to this purpose, as the set was originally open to a public place, meaning that people could do obscene things behind the presenters. The new set with Smart Glass allows the street scene to be visible at times, or replaced with either opaque or transparent blue colouring, masking the view.
Bloomberg Television
currently features Smart Glass backgrounds in its studios in New York and London.
The Boeing 787 Dreamliner features electrochromic windows which replace the pull down window shades on existing aircraft. NASA is looking into using electrochromics to manage the thermal environment experienced by the newly developed Orion and Altair space vehicles.
Smart glass has been used in some small-production cars. The Ferrari 575 M Superamerica had an electrochromic roof as standard, and the Maybach
has a PDLC roof as option. Some Polyvision Privacy Glass has been applied in the Maybach 62 car for privacy protection purposes.
A Hong Kong office uses 130 square meters of Polyvision Privacy Glass, which is available in sizes up to 1,500 x 3,200 mm.
MagicGlas™ Smart Glass from GlasNovations Ltd has been used in a number of projects across United Kingdom, Ireland, Middle East and India. A Conservatory roof-light in Greater London has over 38 square meters of MagicGlas™ panels. A private home in Gleneagles Golf Course, Scotland has a large MagicGlas™ partition around the indoor swimming pool, gym and Sunbed/massage room. MagicGlas™ has recently delivered the world's largest switchable glass panel, with dimensions of 4850mm x 1400mm.
ICE 3
high speed trains use electrochromatic glass panels between the passenger compartment and the driver's cabin.
The elevator
s in the Washington Monument
use smart glass in order for passengers to view the commemorative stones inside the monument.
Window
A window is a transparent or translucent opening in a wall or door that allows the passage of light and, if not closed or sealed, air and sound. Windows are usually glazed or covered in some other transparent or translucent material like float glass. Windows are held in place by frames, which...
s or skylights, refers to electrically switchable glass
Glass
Glass is an amorphous solid material. Glasses are typically brittle and optically transparent.The most familiar type of glass, used for centuries in windows and drinking vessels, is soda-lime glass, composed of about 75% silica plus Na2O, CaO, and several minor additives...
or glazing which changes light transmission properties when voltage is applied.
Certain types of smart glass can allow users to control the amount of light
Light
Light or visible light is electromagnetic radiation that is visible to the human eye, and is responsible for the sense of sight. Visible light has wavelength in a range from about 380 nanometres to about 740 nm, with a frequency range of about 405 THz to 790 THz...
and heat
Heat
In physics and thermodynamics, heat is energy transferred from one body, region, or thermodynamic system to another due to thermal contact or thermal radiation when the systems are at different temperatures. It is often described as one of the fundamental processes of energy transfer between...
passing through: with the press of a button, it changes from transparent to translucent
Opacity (optics)
Opacity is the measure of impenetrability to electromagnetic or other kinds of radiation, especially visible light. In radiative transfer, it describes the absorption and scattering of radiation in a medium, such as a plasma, dielectric, shielding material, glass, etc...
, partially blocking light while maintaining a clear view of what lies behind the window. Another type of smart glass can provide privacy
Privacy
Privacy is the ability of an individual or group to seclude themselves or information about themselves and thereby reveal themselves selectively...
at the turn of a switch.
Smart glass technologies include electrochromic devices, suspended particle devices, micro-blinds and liquid crystal devices.
The use of smart glass can save costs for heating, air-conditioning
HVAC
HVAC refers to technology of indoor or automotive environmental comfort. HVAC system design is a major subdiscipline of mechanical engineering, based on the principles of thermodynamics, fluid mechanics, and heat transfer...
and lighting
Lighting
Lighting or illumination is the deliberate application of light to achieve some practical or aesthetic effect. Lighting includes the use of both artificial light sources such as lamps and light fixtures, as well as natural illumination by capturing daylight...
and avoid the cost of installing and maintaining motorized light screens or blind
Window blind
A window blind is a type of window coverings. There are many different kinds of window blinds, using different systems and materials. A typical window blind is made with slats of fabric, wood, plastic or metal that adjust by rotating from an open position to a closed position by allowing slats to...
s or curtain
Curtain
A curtain is a piece of cloth intended to block or obscure light, or drafts, or water in the case of a shower curtain. Curtains hung over a doorway are known as portières...
s. When opaque, liquid crystal or electrochromic smart glass blocks most UV, thereby reducing fabric fading; for SPD-type smart glass, this is achieved when used in conjunction with low emissivity
Emissivity
The emissivity of a material is the relative ability of its surface to emit energy by radiation. It is the ratio of energy radiated by a particular material to energy radiated by a black body at the same temperature...
coatings.
Critical aspects of smart glass include installation costs, the use of electricity, durability, as well as functional features such as the speed of control, possibilities for dimming, and the degree of transparency of the glass.
Electrochromic devices
Electrochromic devices change light transmission properties in response to voltage and thus allow control over the amount of light and heat passing through. In electrochromic windows, the electrochromic material changes its opacityOpacity (optics)
Opacity is the measure of impenetrability to electromagnetic or other kinds of radiation, especially visible light. In radiative transfer, it describes the absorption and scattering of radiation in a medium, such as a plasma, dielectric, shielding material, glass, etc...
: it changes between a colored, translucent state (usually blue) and a transparent state. A burst of electricity is required for changing its opacity, but once the change has been effected, no electricity is needed for maintaining the particular shade which has been reached. Darkening occurs from the edges, moving inward, and is a slow process, ranging from many seconds to several minutes depending on window size. Electrochromic glass provides visibility even in the darkened state and thus preserves visible contact with the outside environment. It has been used in small-scale applications such as rearview mirrors. Electrochromic technology also finds use in indoor applications, for example, for protection of objects under the glass of museum display cases and picture frame glass from the damaging effects of the UV and visible wavelengths of artificial light.
Recent advances in electrochromic materials pertaining to transition-metal hydride electrochromics have led to the development of reflective hydrides, which become reflective rather than absorbing, and thus switch states between transparent and mirror-like.
Recent advancements in modified porous nano-crystalline films have enabled the creation of electrochromic display. The single substrate display structure consists of several stacked porous layers printed on top of each other on a substrate modified with a transparent conductor (such as ITO or PEDOT:PSS). Each printed layer has a specific set of functions. A working electrode consists of a positive porous semiconductor (say Titanium Dioxide, TiO2) with adsorbed chromogens (different chromogens for different colors). These chromogens change color by reduction or oxidation. A passivator is used as the negative of the image to improve electrical performance. The insulator layer serves the purpose of increasing the contrast ratio and separating the working electrode electrically from the counter electrode. The counter electrode provides a high capacitance to counterbalances the charge inserted/extracted on the SEG electrode (and maintain overall device charge neutrality). Carbon is an example of charge reservoir film. A conducting carbon layer is typically used as the conductive back contact for the counter electrode. In the last printing step, the porous monolith structure is overprinted with a liquid or polymer-gel electrolyte, dried, and then may be incorporated into various encapsulation or enclosures, depending on the application requirements. Displays are very thin, typically 30 micrometer, or about 1/3 of a human hair. The device can be switched on by applying a electrical potential to the transparent conducting substrate relative to the conductive carbon layer. This causes a reduction of viologen molecules (coloration) to occur inside the working electrode. By reversing the applied potential or providing a discharge path, the device bleaches. A unique feature of the electrochromic monolith is the relatively low voltage (around 1 Volt) needed to color or bleach the viologens. This can be explained by the small over- potentials needed to drive the electrochemical reduction of the surface adsorbed viologens/chromogens.
Suspended particle devices
In suspended particle devices (SPDs), a thin filmThin film
A thin film is a layer of material ranging from fractions of a nanometer to several micrometers in thickness. Electronic semiconductor devices and optical coatings are the main applications benefiting from thin film construction....
laminate
Laminate
A laminate is a material that can be constructed by uniting two or more layers of material together. The process of creating a laminate is lamination, which in common parlance refers to the placing of something between layers of plastic and gluing them with heat and/or pressure, usually with an...
of rod-like particles suspended
Suspension (chemistry)
In chemistry, a suspension is a heterogeneous fluid containing solid particles that are sufficiently large for sedimentation. Usually they must be larger than 1 micrometer. The internal phase is dispersed throughout the external phase through mechanical agitation, with the use of certain...
in a fluid is placed between two glass or plastic layers, or attached to one layer. When no voltage is applied, the suspended particles are arranged in random orientations and tend to absorb light, so that the glass panel looks dark (or opaque), blue or, in more recent developments, grey or black colour. When voltage is applied, the suspended particles align and let light pass. SPDs can be manually or automatically “tuned” to precisely control the amount of light, glare and heat passing through, reducing the need for air conditioning during the summer months and heating during winter. Other advantages include reduction of buildings' carbon emissions and the elimination of a need for expensive window dressings.
Polymer dispersed liquid crystal devices
In polymer dispersed liquid crystalLiquid crystal
Liquid crystals are a state of matter that have properties between those of a conventional liquid and those of a solid crystal. For instance, an LC may flow like a liquid, but its molecules may be oriented in a crystal-like way. There are many different types of LC phases, which can be...
devices (PDLCs), liquid crystals are dissolved or dispersed into a liquid polymer followed by solidification or curing of the polymer. During the change of the polymer from a liquid to solid, the liquid crystals become incompatible with the solid polymer and form droplets throughout the solid polymer. The curing conditions affect the size of the droplets that in turn affect the final operating properties of the "smart window". Typically, the liquid mix of polymer and liquid crystals is placed between two layers of glass or plastic that include a thin layer of a transparent, conductive material followed by curing of the polymer, thereby forming the basic sandwich structure of the smart window. This structure is in effect a capacitor.
Electrodes from a power supply are attached to the transparent electrodes. With no applied voltage, the liquid crystals are randomly arranged in the droplets, resulting in scattering of light as it passes through the smart window assembly. This results in the translucent, "milky white" appearance. When a voltage is applied to the electrodes, the electric field formed between the two transparent electrodes on the glass causes the liquid crystals to align, allowing light to pass through the droplets with very little scattering and resulting in a transparent state. The degree of transparency can be controlled by the applied voltage. This is possible because at lower voltages, only a few of the liquid crystals align completely in the electric field, so only a small portion of the light passes through while most of the light is scattered. As the voltage is increased, fewer liquid crystals remain out of alignment, resulting in less light being scattered. It is also possible to control the amount of light and heat passing through, when tints and special inner layers are used. It is also possible to create fire-rated and anti X-Ray versions for use in special applications. Most of the devices offered today operate in on or off states only, even though the technology to provide for variable levels of transparency is easily applied. This technology has been used in interior and exterior settings for privacy control (for example conference rooms, intensive-care areas, bathroom/shower doors) and as a temporary projection screen
Projection screen
A projection screen is an installation consisting of a surface and a support structure used for displaying a projected image for the view of an audience. Projection screens may be permanently installed, as in a movie theater; painted on the wall; or semi-permanent or mobile, as in a conference room...
.
MagicGlas™ panels use a lamination process which encapsulates a PDLC film between two or more glass sheets. By means of a minute electrical current, users can immediately switch the MagicGlas™ from clear to private (opaque) and vice versa. When the electrical supply is switched on, the liquid crystal molecules align, the panel instantly clears and light passes through. When the power is switched off the liquid crystal molecules are randomly oriented, scattering light, and the panel becomes opaque.
Micro-blinds
Micro-blinds—currently under development at the National Research Council (Canada)—control the amount of light passing through in response to applied voltage. Micro-blinds are composed of rolled thin metal blinds on glass. They are very small and thus practically invisible to the eye. The metal layer is deposited by magnetron sputtering and patterned by laser or lithography process. The glass substrate includes a thin layer of a transparent conductive oxide (TCO) layer. A thin insulator is deposited between the rolled metal layer and the TCO layer for electrical disconnection. With no applied voltage, the micro-blinds are rolled and let light pass through. When there is a potential difference between the rolled metal layer and the transparent conductive layer, the electric field formed between the two electrodes causes the rolled micro-blinds to stretch out and thus block light. The micro-blinds have several advantages including switching speed (milliseconds), UV durability, customized appearance and transmission. Theoretically, the blinds are simple and cost-effective to fabricate.A video available on youtube describes briefly the micro-blinds.
SunValve
SunValve is an invention of Norwegian inventor Kim Øyhus. The SunValve is a low cost, simple mechanical type of smart window. SunValve is composed of two retro reflective panels mounted back-to-back with a narrow gap in between. When a liquid with the same refractive index as that of the panels is pumped into the cavity between them, the SunValve turns transparent. When the liquid is pumped out, the SunValve turns retro reflective again.Related areas of technology
The expression smart glass can be interpreted in a wider sense to include also glazings that change light transmission properties in response to an environmental signal such as light or temperature.- Different types of glazing can show a variety of chromic phenomenaChromismIn chemistry, chromism is a process that induces a change, often reversible, in the colors of compounds. In most cases, chromism is based on a change in the electron states of molecules, especially the π- or d-electron state, so this phenomenon is induced by various external stimuli which can alter...
, that is, based on photochemicalPhotochemistryPhotochemistry, a sub-discipline of chemistry, is the study of chemical reactions that proceed with the absorption of light by atoms or molecules.. Everyday examples include photosynthesis, the degradation of plastics and the formation of vitamin D with sunlight.-Principles:Light is a type of...
effects the glazing changes its light transmission properties in response to an environmental signal such as light (photochromismPhotochromismPhotochromism is the reversible transformation of a chemical species between two forms by the absorption of electromagnetic radiation, where the two forms have different absorption spectra. Trivially, this can be described as a reversible change of colour upon exposure to light...
), temperature (thermochromismThermochromismThermochromism is the ability of substance to change color due to a change in temperature. A mood ring is an excellent example of this, but it has many other uses such as baby bottles and kettles. Thermochromism is one of several types of chromism.The two basic approaches are based on liquid...
), or voltage (electrochromismElectrochromismElectrochromism is the phenomenon displayed by some materials of reversibly changing color when a burst of charge is applied. Various types of materials and structures can be used to construct electrochromic devices, depending on the specific applications....
). - Liquid crystals, when they are in a thermotropicThermotropicA liquid crystal is thermotropic if the order of its components is determined or changed by temperature.If temperature is too high, the rise in energy and therefore in motion of the components will induce a phase change: the LC will become an isotropic liquid.If, on the contrary, temperature is...
state, can change light transmission properties in response to temperature. - Recent advances in electrochromic materials have led to the discovery that transition metal hydride electrochromics that create a reflective face instead of an absorbent. These materials have the same idea but go about the problem in a different way by switching between a transparent state when they are off to a reflective state when a voltage is applied. Switchable mirrors were originally developed by Tom Richardson and Jonathon Slack of Berkeley Lab’s Environmental Energy Technologies Division. They used rare earth metals and created the first metal-hydride switchable mirrors. Low emittance coatings reject unwanted thermal heat due to solar infrared21. These mirrors have become common place in cars’ rearview mirrors in order to block the glare of following vehicles. An optically absorbing electrochromic color reduces the reflection intensity. These mirrors must be fully transformed to a reflective state as muted reflection must persist in the darkened state. Originally a metal, they are converted into a transparent hydride by injecting hydrogen in a gas or liquid phase. It then switches to a reflective state.
- Various metals have been looked into. Thin Ni-Mg films have low visible transmittance and are reflective. When they are exposed to H2 gas or reduced by an alkaline electrolyte, they become transparent. This transition is attributed to the formation of nickel magnesium hydride, Mg2NiH4. Films were created by cosputtering from separate targets of Ni and Mg to facilitate variations in composition. Single-target d.c. magnetron sputtering could be used eventually which would be relatively simple compared to deposition of electrochromic oxides, making them more affordable. Lawrence Berkeley National Laboratory determined that new transition metals were cheaper and less reactive but contained the same qualities further reducing the cost .
- Tungsten doped Vanadium dioxide VO2 coating reflects infrared light when the temperature rises over 29 degrees Celsius, to block out sunlight transmission through windows at high ambient temperatures.
These types of glazing cannot be controlled manually. In contrast, all electrically switched smart windows can be made to automatically adapt their light transmission properties in response to temperature or brightness by integration with a thermometer
Thermometer
Developed during the 16th and 17th centuries, a thermometer is a device that measures temperature or temperature gradient using a variety of different principles. A thermometer has two important elements: the temperature sensor Developed during the 16th and 17th centuries, a thermometer (from the...
or photosensor
Photodetector
Photosensors or photodetectors are sensors of light or other electromagnetic energy. There are several varieties:*Active pixel sensors are image sensors consisting of an integrated circuit that contains an array of pixel sensors, each pixel containing a both a light sensor and an active amplifier...
, respectively
The topic of smart windows in a further sense includes LED Embedded Films which may be switched on at reduced light intensity. The process of laminating these LED embedded films between glass will allow the production of Transparent LED embedded glass
Transparent LED embedded Glass
Transparent LED-embedded glass is a new composite material containing light-emitting diodes . It is used as building material and as glass type for many different products. This new technology enables materials, new applications in electronics and architecture...
es. As most glass companies are not skilled in mounting LEDs (Light Emitting Diodes) onto metallized glass, the LEDs are located on a separate transparent conductive polymeric interlayer that may be laminated by any glass lamination unit.
Production technologies
Smart glass is produced by means of lamination of two or more glass or polycarbonate sheets.
Examples of use
Smart glass using one of the aforementioned technologies has been seen in a number of high profile applications. Large scale installations were completed at the Guinness Storehouse in Dublin where over 800,000 people per year can see smart glass being used in interactive displays and privacy windows. Smart glass was used to launch the Nissan Micra CC in London using a four-sided glass box made up of 150 switchable glass panels which switched in sequence to create a striking outdoor display. The main use for smart glass is in internal partitions where many companies now enjoy the ability to switch screens and doors from clear to private.Smart glass has found uses in the healthcare industry, where easily cleaned surfaces are essential and there are considerations of patient privacy. Smart glass products can replace traditional blind systems that are difficult to clean and can harbor dirt and bugs. Research has shown that patient comfort can help reduce recovery time.
One of the most popular Smart Glass applications is as projection screen
Projection screen
A projection screen is an installation consisting of a surface and a support structure used for displaying a projected image for the view of an audience. Projection screens may be permanently installed, as in a movie theater; painted on the wall; or semi-permanent or mobile, as in a conference room...
s.
Polyvision privacy glass by Polytron Technologies, Inc. was shown at the Shanghai Expo 2010. Five privacy glass panels formed a curved window that, together with the control console, resembled a professional wheel house.
Another example of use is the installation of PDLC-based smart glass, in the EDGE, a glass cube which protrudes out from the 88th floor skydeck of the world's highest residential tower, Eureka Towers, located in Melbourne. The cube can hold 13 people. When it extends out of the building by 3 metres, the glass is made transparent, giving the cube's occupants views of Melbourne from a height of 275 metres. The same type of smart glass has also been proposed for use in hospital settings to controllably provide patients with privacy as needed.
PDLC technology was used in a display to unveil the Nissan GTR at the Canadian International Auto Show in Toronto.
In the media, the updated set for the Seven Network
Seven Network
The Seven Network is an Australian television network owned by Seven West Media Limited. It dates back to 4 November 1956, when the first stations on the VHF7 frequency were established in Melbourne and Sydney.It is currently the second largest network in the country in terms of population reach...
's Sunrise
Sunrise (TV program)
Sunrise is an Australian breakfast television program, broadcast on the Seven Network. On weekdays the programme follows Seven Early News, and runs from 6am through to 9am.-History:...
program features a Smart Glass background that uses liquid crystal switchable glass (AGP UMU Glass) supplied by Architectural Glass Projects. The technology is especially suited to this purpose, as the set was originally open to a public place, meaning that people could do obscene things behind the presenters. The new set with Smart Glass allows the street scene to be visible at times, or replaced with either opaque or transparent blue colouring, masking the view.
Bloomberg Television
Bloomberg Television
Bloomberg Television is a 24-hour global network broadcasting business and financial news. It is distributed globally, reaching over 200 million homes worldwide. It is owned and operated by Bloomberg L.P...
currently features Smart Glass backgrounds in its studios in New York and London.
The Boeing 787 Dreamliner features electrochromic windows which replace the pull down window shades on existing aircraft. NASA is looking into using electrochromics to manage the thermal environment experienced by the newly developed Orion and Altair space vehicles.
Smart glass has been used in some small-production cars. The Ferrari 575 M Superamerica had an electrochromic roof as standard, and the Maybach
Maybach 57 and 62
The Maybach 57 and 62 were the first automobile models of the Maybach brand since the brand's revival by DaimlerChrysler AG . They are derived from the Mercedes-Benz Maybach concept car presented at the 1997 Tokyo Motor Show...
has a PDLC roof as option. Some Polyvision Privacy Glass has been applied in the Maybach 62 car for privacy protection purposes.
A Hong Kong office uses 130 square meters of Polyvision Privacy Glass, which is available in sizes up to 1,500 x 3,200 mm.
MagicGlas™ Smart Glass from GlasNovations Ltd has been used in a number of projects across United Kingdom, Ireland, Middle East and India. A Conservatory roof-light in Greater London has over 38 square meters of MagicGlas™ panels. A private home in Gleneagles Golf Course, Scotland has a large MagicGlas™ partition around the indoor swimming pool, gym and Sunbed/massage room. MagicGlas™ has recently delivered the world's largest switchable glass panel, with dimensions of 4850mm x 1400mm.
ICE 3
ICE 3
ICE 3 is a family of high-speed EMUs of Deutsche Bahn. It includes classes 403 and 406, which are known as ICE 3 and ICE 3M respectively...
high speed trains use electrochromatic glass panels between the passenger compartment and the driver's cabin.
The elevator
Elevator
An elevator is a type of vertical transport equipment that efficiently moves people or goods between floors of a building, vessel or other structures...
s in the Washington Monument
Washington Monument
The Washington Monument is an obelisk near the west end of the National Mall in Washington, D.C., built to commemorate the first U.S. president, General George Washington...
use smart glass in order for passengers to view the commemorative stones inside the monument.
In popular culture
- The 1982 film Blade RunnerBlade RunnerBlade Runner is a 1982 American science fiction film directed by Ridley Scott and starring Harrison Ford, Rutger Hauer, and Sean Young. The screenplay, written by Hampton Fancher and David Peoples, is loosely based on the novel Do Androids Dream of Electric Sheep? by Philip K...
contains an early depiction of smart glass in a scene in which a room is darkened with a smart glass-like shade so Rick Deckard, played by Harrison FordHarrison FordHarrison Ford is an American film actor and producer. He is famous for his performances as Han Solo in the original Star Wars trilogy and as the title character of the Indiana Jones film series. Ford is also known for his roles as Rick Deckard in Blade Runner, John Book in Witness and Jack Ryan in...
, can administer a polygraph-style test to determine whether Rachael, portrayed by Sean YoungSean YoungSean Young is an American actress, best known for her performance in films from the 1980s such as Blade Runner, Dune, and No Way Out.-Early life:...
, is an organic robot known as a replicantReplicantA replicant is a bioengineered or biorobotic being created in the film Blade Runner . The Nexus series—genetically designed by the Tyrell Corporation—are virtually identical to an adult human, but have superior strength, agility, and variable intelligence depending on the model...
. - Smart glass is seen in the 2002 motion picture The Sum of all FearsThe Sum of All FearsThe Sum of All Fears is the best-selling thriller novel by Dan Fogelman and Tom Clancy, and part of the Jack Ryan series. It was the fourth book of the series to be turned into a film. An interesting historical note is that this book was released just days before the Moscow uprising in 1991, which...
, in which Jack RyanJack RyanJack Ryan may refer to:*Jack Ryan , a fictional character in a series of novels by Tom Clancy*Jack Ryan , former candidate for United States Senator from Illinois and ex-husband of actress Jeri Ryan...
, played by Ben AffleckBen AffleckBenjamin Géza Affleck-Boldt , better known as Ben Affleck, is an American actor, film director, writer, and producer. He became known with his performances in Kevin Smith's films such as Mallrats and Chasing Amy...
, is ushered into a secret room in the PentagonPentagonIn geometry, a pentagon is any five-sided polygon. A pentagon may be simple or self-intersecting. The sum of the internal angles in a simple pentagon is 540°. A pentagram is an example of a self-intersecting pentagon.- Regular pentagons :In a regular pentagon, all sides are equal in length and...
, the windows of which whiten over as the door is shut. - Smart glass can be seen in the third season of the television series 2424 (TV series)24 is an American television series produced for the Fox Network and syndicated worldwide, starring Kiefer Sutherland as Counter Terrorist Unit agent Jack Bauer. Each 24-episode season covers 24 hours in the life of Bauer, using the real time method of narration...
, where Jack Bauer changed the visibility to frosted glass to conceal the view as he was injecting heroin. - Smart glass is mentioned in Season Three, Episode Five of CSI:Miami, entitled "Legal", in which a young lady working undercover to expose underage drinking is murdered in a room shielded by what Ryan WolfeRyan WolfeDetective Ryan Wolfe is a fictional character on the CBS crime drama CSI: Miami, portrayed by Jonathan Togo.-Background:Ryan Wolfe, a former patrol officer, is hired after veteran CSI Tim Speedle is killed on the job. He has a strong background in science, having majored in chemistry at Boston...
refers to as "intelligent glass", where closing the door completes an electrical circuit, making the glass frost over and become opaque. The episode first aired in 2004. - Smart glass is seen in the television series Lie To MeLie to MeLie to Me is a 2009-2011 American television series.Lie to Me may also refer to:* Lie to Me , a South Korean drama series* "Lie to Me" , an episode of Buffy the Vampire Slayer...
with the interrogation/interview room at the Lightman Group offices consisting of what amounts to a room-sized box within a larger room, with smart glass walls. The walls appear to be white and opaque most of the time, but can be rendered clear to reveal those observing a subject from without.
See also
- SAGE ElectrochromicsSAGE ElectrochromicsSAGE Electrochromics, Inc. is a specialized window glass developer based in Faribault, Minnesota. The company develops electronically tintable smart glass , for use in building windows and skylights, that can be switched from clear to darkly tinted at the click of a button, or programmed to respond...
- Heatable GlassHeatable GlassElectrically heatable glass and windows are relatively new products, which help solve problems in the design of buildings and vehicles.The idea of heating glass is based on the use of energy-efficient low-emissive glass, which is generally simple silicate glass with a special metallic oxides...
- C.G. GranqvistClaes-Göran GranqvistClaes-Göran Granqvist was born in Helsingborg, Sweden, in 1946. He is one of the leading figures of Swedish and international science in various fields including nanomaterials; green nanotechnology; materials for solar energy utilization and energy efficiency , electrochromic materials...
, Handbook of Inorganic Electrochromic Materials, Elsevier, Amsterdam, 1995, reprinted 2002, approx. 650 pages.
External links
- Electronic Smart Glasses at GlassOnWeb
- Chromogenics, in: Windows and Daylighting at Lawrence Berkeley National Laboratory
- Smart glass blocks infrared when heat is on, NewScientist.com news service
- PDLC switchable windows, Liquid Crystal Institute at Kent State University
- Switchable Glass: A possible medium for Evolvable Hardware, NASA conference on Adaptive Hardware Systems, IEEE CS Press, pp 81–87, 2006.
- Switchable Glazing Windows Change the light transmittance, transparency, or shading of windows at toolbase.org