MORPHOLOGY OF REFLECTION HOLOGRAMS FORMED IN-SITU USING POLYMER-DISPERSED LIQUID-CRYSTALS

The morphology of a reflection grating formed using a polymer-disperse d liquid crystalline material system is examined using low-voltage hig h-resolution scanning electron and transmission electron microscopy. T he grating is formed by establishing a fringe pattern in the intensity profile of an argon-ion laser line (lambda = 488 nm) leading to a per iodic anisotropic cure through the thickness of the film. The in situ, one-step procedure produces periodic layers of polymer- and LC-rich p lanes lying parallel to the film surface. Droplet diameters are very s mall (<100 nm) and little coalescence of individual droplets is observ ed. The grating spacing measured from electron micrographs (153 nm) ne arly corresponds to the expected spacing from the observed reflection notch at lambda = 472 nm. Copyright (C) 1996 Elsevier Science Ltd.