Abstract
Directly written by a ultra-short femto-second laser pulse, we report the phase separation and pattern formation induced by polymerization in a liquid-crystal-monomer mixture. By varying the scanning speed of optical fields along a line, pattern transitions of photon-induced polymer structures are illustrated in shapes of double-humped, singlehumped, and broken stripes. The optical microscope images taken in experiments are in a good agreement with numerical simulations based on a modified set of coupled 2+1 dimensional diffusion equations. The demonstration in this work provides a step for controlling phase separation morphologies as well as transferring patterns in polymer-dispersed liquid crystals. © 2011 Optical Society of America.