Charge coupled frame transfer imaging devices with interlaced readout and blooming suppression

A charge coupled image sensor to be used in conventional television applications has to be read out in two progressively scanned, 2:1 interlaced fields. A difficulty arises in frame transfer imaging devices, since they are basically shift registers that move the whole charge pattern in unison. A modified form of interlacing has been devised which offers a resolution per scan line in the display that is comparable to what is produced in an electron beam scanned arrangement. Each charge transfer cell is elongated in the vertical direction to cover the distance corresponding to two scan lines in the display. The information to be presented in two consecutive fields is integrated underneath different sets of electrodes, within this stretched resolution cell, to match the center of charge collection with the corresponding location of the scan line in the display. Several implementations of this scheme have been tested experimentally and compared to the theoretical resolution limit.