An optically controlled liquid crystal device using azopolymer films

We have developed a liquid crystal (LC) device that is totally controlled u sing light. The initial alignment is made by optically buffing the azopolym er film with two coherent argon laser beams. Surface relief gratings have b een optically induced on an assembled cell filled with LC, A single linearl y polarized argon laser beam is then employed to irradiate the sample and p hotoinduce a twisted alignment structure, This can then be erased by a circ ularly polarized beam. The alignment information can also be erased by heat ing to the glass transition temperature of the azopolymer film.