Polymer dispersed liquid crystals were invented at Kent State University in 1983. A major application of these materials is in switchable windows.
The windows change from opaque to clear with the flip of a switch. Popular uses are glass walls in offices, conference rooms, lobbies, and store fronts. Privacy glass also provides unique opportunities for use by homeowners in bathrooms, entryways, family rooms, bedrooms, and skylights.
The windows use the same voltage as standard household appliances. Multiple windows can be controlled from one switch and can be connected to a timer.
In the scattering (opaque) state, the glass diffuses direct sunlight and eliminates 99% of the UV rays that fade carpet and furniture.
How it works:
|PDLCs operate on the principle of electrically controlled light scattering. They consist of liquid crystal droplets durrounded by a polymer mixture sandwiched between two pieces of conducting glass. When no electricity is applied the liquid crystal droplets are randomly oriented, creating an opaque state. When electricity is applied the liquid crystals align parallel to the electric field and light passes through, creating a transparent state.|