146. One- and two-dimensional anisotropic diffractive gratings formed by periodic orthogonal molecular alignment in a hydrogen-bonded liquid crystalline polymer, A. Emoto, S. Manabe, T. Shioda, H. Ono, and N. Kawatsuki, J. Appl. Phys. 105 (2009) 103514.


Anisotropic diffractive gratings having periodic orthogonal molecular alignments are formed by a linearly-polarized ultraviolet (LPUV) exposure through a photomask in hydrogen (H)-bonding liquid crystalline polymers (H-LCPs) using a unique molecular reorientation behavior. H-bonded side-chain groups of H-LCPs play an important role in the molecular reorientation and the resultant optical anisotropy originating from an intermolecular network composition. To evaluate its potential for optical applications, one- and two-dimensional diffractive gratings were fabricated and analyzed by both polarization optical microscopy (POM) and diffraction characteristics. As a result, anisotropic gratings using H-LCP were obtained with a high diffraction efficiency that was 80% of the theoretical maximum efficiency (33.9%) of thin diffractive gratings. Results of experimental and theoretical investigation reveal that the resultant molecular direction and optical anisotropy are generated and controlled by LPUV exposure. This agrees well with H-LCP behavior confirmed on the basis of polarization UV-visible absorption spectra.

Get Full Text


無料 アクセス解析インプラント