Detailed experimental investigation on recording of switchable diffractiongratings in polymer dispersed liquid crystal films by UV laser curing

Results on UV recording of diffraction gratings in polymer dispersed liquid crystal (PDLC) films made with commercially available components are prese nted. Gratings have been recorded during the curing process by exposing the pre-PDLC mixture to a UV laser interference pattern. The grating morpholog y, as well as the temporal evolution of the diffraction efficiency, have be en experimentally investigated to determine their dependence on curing inte nsity, liquid crystal concentration and spatial period of the grating. In o ptimal conditions the resulting diffraction efficiency of the first diffrac ted beam achieved its theoretical limit for transparent gratings, that is 3 3%. Possibilities of volume (reflective) grating recording in these materia ls are also discussed.