Image subtraction using polarization modulation of liquid-crystal television.

A method of real-time image subtraction is proposed that uses successive light transmission through two similar liquid-crystal television (LCTV) panels. The polarization modulation properties of light transmitting through LCTV's are investigated theoretically and experimentally for the case of when the video signals are applied to the LCTV's. Image subtraction is accomplished by the approximate rotations of the linear polarization of light through the LCTV's.