Patent ID: 8130441

Claim:
An electrophoretic light modulator, comprising: an optically transparent upper electrode through which light can pass; a lower electrode; an enclosed volume between the upper electrode and the lower electrode; an optically transparent electrophoretic fluid within the enclosed volume; a voltage source coupled to the upper electrode and the lower electrode, the voltage source operable to apply a bias between the upper electrode and the lower electrode and further operable to switch between a first bias state and a second bias state; a plurality of electrophoretic particles suspended in the electrophoretic fluid, the electrophoretic particles configured to absorb the light and responsive to the bias applied between the upper electrode and the lower electrode; and a plurality of substantially parallel reflecting surfaces comprising a high index of optical refraction, each parallel reflecting surface is substantially parallel to at least one other parallel reflecting surface and to the upper electrode, at least one of the reflecting surfaces is between the upper electrode and the lower electrode and at least one of the parallel reflecting surfaces is electrically coupled to the lower electrode the plurality of reflecting surfaces arranged so that when the first bias state is applied between the upper electrode and the lower electrode the plurality of electrophoretic particles obscure the plurality of reflecting surface from the light to absorb at least portion of the light and when the second bias state is applied between the upper electrode and the lower electrode the plurality of electrophoretic particles expose the plurality of reflecting surfaces to the light to reflect at least a portion of the light.