Patent ID: 7535614

Claim:
An electrical window control system comprising: a variable transmission window comprising: a first substantially transparent substrate; a second substantially transparent substrate, wherein said first and second substantially transparent substrates define an area; and a variable transmittance material that occupies at least a portion of said area; a power source that supplies an electrical power to said variable transmittance material, wherein an altering of a transmittance state of said variable transmittance material is based upon altering said supplied electrical power; at least one light source that emits light towards said variable transmission window, such that said emitted light is adapted to substantially propagate through at least one of said first and second substantially transparent substrates based upon said transmittance state of said variable transmittance material; at least one sensor in optical communication with said at least one of light source, wherein said at least one sensor receives at least a portion of said emitted light that propagates through at least one of said first and second substantially transparent substrates, and communicates a signal that corresponds to said received light; and a controller in communication with said at least one sensor, wherein said controller receives and compares said signal communicated from said at least one sensor to a reference value, and said controller controls an electrical power supplied from said power source to said variable transmittance material based upon said comparison of said communicated signal and said reference value, such that said transmittance state of said variable transmittance material is altered with respect to said light received by said at least one sensor.