Document Type
Article
Publication Date
3-1-2002
Abstract
The stylus of an atomic force microscope is used to scribe preferred directions for liquid-crystal alignment on a polyimide-coated substrate. The opposing substrate that comprises the liquid-crystal cell is rubbed unidirectionally, resulting in a twisted nematic structure associated with each micrometer-sized pixel The polarization of light entering from the uniformly rubbed substrate rotates with the nematic director by a different amount in each pixel, and each of the two emerging polarization eigenmodes interferes separately. Two examples are discussed: A square grating that allows only odd-order diffraction peaks and a grating that combines rotation with optical retardation to simulate a blazed grating for circularly polarized light. The gratings can be electrically switched if used with semitransparent electrodes.
Keywords
polarization gratings, computer simulation, electrodes, light interference, light polarization, nematic liquid crystals, diffraction gratings, atomic force microscopy
Publication Title
Applied Optics
Rights
© 2002 Optical Society of America. This paper was published in Applied Optics and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: [http://www.opticsinfobase.org/ao/abstract.cfm?URI=ao-41-7-1246]. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.
Recommended Citation
Bing Wen, Rolfe G. Petschek, and Charles Rosenblatt, "Nematic liquid-crystal polarization gratings by modification of surface alignment," Appl. Opt. 41, 1246-1250 (2002)