Optically Addressable Input Circuit for Two-Dimensional Image Sensing

ABSTRACTUsing the combination of a novel amorphous silicon (a-Si) photosensing element and four a-Si thin-film transistors (TFTs) we have developed a circuit which has been incorporated into a two-dimensional image sensor to provide gain at the pixel level. Our circuit only requires two global connections and the complete array is fully process compatible with standard a-Si TFT fabrication procedures. This contrasts with conventional a-Si imaging arrays which have no gain at the pixel level, require an additional global power line, and necessitate a separate sensor deposition.