Photosensitive device comprising photoconductive and photovoltaic layers

Claim 1

A photo electric assembly, adapted for connection in an image correlating system including current measuring means, comprising: a plurality of layers each having opposed first and second surfaces of extended area relative to the cross sectional thickness thereof, each layer being substantially continuous over its area, said layers being sandwiched together in parallel plane relationship with substantially the entire area of a surface of one layer in intimate contact with a substantial area of a surface of an adjacent layer; a first one of said layers being photoconductive; a second one of said layers being photovoltaic; a third one of said layers comprising a film of optically opaque electrically conductive material, said third layer sandwiched between the second surface of said first layer and the first surface of said second layer and in electrical contact with said first and second layers over said extended areas thereof; and fourth and fifth ones of said layers each comprising a thin conductive transparent film, said film of said fourth layer disposed adjacent the first surface of said first layer and in electrical contact therewith over said extended area thereof, and said film of said fifth layer disposed adjacent the second surface of said second layer and in electrical contact therewith over said extended area thereof; said fourth layer being sufficiently thin to transmit a first light image directed thereto to activate said first layer, said fifth layer being sufficiently thin to transmit a second light image directed thereto to activate said second layer, said third layer blocking said first image from said second layer and blocking said second image from said first layer, said fourth and fifth layers adapted to be connected to current measuring means for providing a measure of current flow through said plurality of layers as an indication of the correlation between said first and second images.