ELECTRO-OPTICAL DISPLAY DEVICE EMPLOYING LIQUID CRYSTALS

摘要

An electro-optical display system comprises a display screen including one or more juxtaposed sets of nematic liquid crystal and photoconductive layers bounded by transparent electrodes. The screen is scanned by scanning light while modulated bias voltages are applied across the liquid crystal and photoconductive layers. Images appearing on the screen are viewable by reflected ambient light to which the photoconductive layers are transparent. Colored dyes mixed with the nematic liquid crystals result in colored images on the screen. Cholesteric liquid crystal mixed with the nematic liquid crystal retains the images on the screen for predetermined periods of time. The images are viewable at either side of the screen. The screen can be internally illuminated.