Smart glass
This can be used to prevent sunlight and heat from entering a building during hot days, improving energy efficiency.
The most common active glass technologies used today are electrochromic, liquid crystal, and suspended particle devices (SPD).
[2] When installed in the envelope of buildings, smart glass helps to create climate adaptive building shells,[3] which benefits include things such as natural light adjustment, visual comfort, UV and infrared blocking, reduced energy use, thermal comfort, resistance to extreme weather conditions, and privacy.
Darkening occurs from the edges, moving inward, and is a slow process, ranging from many seconds to 20–30 minutes depending on window size.
Electrochromic glass maintains visibility in its darkened state and thus preserves visual contact with the outside environment.
Recent advancements in modified porous nanocrystalline films have enabled the creation of electrochromic display.
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.
A unique feature of the electrochromic monolith is the relatively low voltage (around 1 Volt) needed to color or bleach the viologens.
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.
In suspended-particle devices (SPDs), a thin film laminate of rod-like nano-scale particles is suspended in a liquid and placed between two pieces of glass or plastic, or attached to one layer.
SPDs can be manually or automatically "tuned" to precisely control the amount of light, glare and heat passing through.
The micro-blinds have several advantages including switching speed (milliseconds), UV durability, customized appearance and transmission.
[15] When the temperature goes above Tp, P1 melts and transitions into amorphous phase which exhibits a large refractive index mismatch with P2, resulting in an opaque appearance.
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.
Smart glass can be used for energy-saving heating and cooling in building by controlling the amount of sunlight which passes through a window.
[19] NASA is looking into using electrochromics to manage the thermal environment experienced by the newly developed Orion and Altair space vehicles.
[20] ICE 3 high speed trains use electrochromic glass panels between the passenger compartment and the driver's cabin.
The city's restroom in Amsterdam's Museumplein square features smart glass for ease of determining the occupancy status of an empty stall when the door is shut, and then for privacy when occupied.
Bombardier Transportation has intelligent on-blur windows in the Bombardier Innovia APM 100 operating on Singapore's Bukit Panjang LRT line, to prevent passengers from peering into apartments while the train is moving[21] and is planning to offer windows using smart glass technology in its Flexity 2 light rail vehicles.
[26] University of Toronto has utilized Smart Film Technology on a curtain wall to provide privacy in their swimming pool viewing area.
