Controllable liquid-crystal transparency for recording of holograms

The efficiency of liquid crystals as light switches is considered. An array consisting of a glass disk with'embedded electrodes, a liquid crystal, and a transparent electrode can be used to record holograms at a rate of 50 cycles per second without loss of high contrast in the image. Liquid crystals with a memory can be used in the preparation of data before input into an optical computer and for output from an electronic computer.