Continuous grey scale image printing on the liquid crystal cell

The continuous grey scale image is printed on the liquid crystal (LC) cell through the similar printing process on a photographic paper. The LC cell is prepared with a rubbed photo-cross-linkable polymer coated substrate whose azimuthal anchoring strength increases by exposing the unpolarized UV light. The cell filled with the LC is exposed to the UV light through a negative film, and is thermally developed and fixed. The twist angle continuously changes from 0degrees to about 90degrees by increasing the exposure, and the positive image with continuous grey levels appears in the LC cell between parallel polarizers. (C) 2005 American Institute of Physics.