Spatially periodic patterning of the anchoring condition of a nematic liquid crystal (NLC) within a polymer matrix via a patterned photopolymerization affords a novel and facile method to prepare electrically switchable diffraction gratings. UV irradiation through a photomask of two comonomers, with opposite tendencies to align the NLC and also with different reactivity ratios, leads to definition of areas with either homeotropic or planar alignment of the NLC. Photopolymerization-induced diffusion of the monomers accounts for the spatial distribution of the concentration of these monomers. The resulting diffraction gratings are switchable under low electric fields and possess structural stability offered by the polymer matrix.
© 2006 Optical Society of America
Diffraction and Gratings
Original Manuscript: June 28, 2005
Revised Manuscript: September 6, 2005
Manuscript Accepted: September 8, 2005
Jian Zhou, David M. Collard, and Mohan Srinivasarao, "Switchable gratings by spatially periodic alignment of liquid crystals via patterned photopolymerization," Opt. Lett. 31, 652-654 (2006)