Optically Controllable Gray-Level Diffraction from a BCT Photonic Crystal Based on Azo Dye-Doped HPDLC  

作　　者：Shing-Trong Wu Chung-Hung Liu Jui-Hsiang Liu Ming-Hsien Li Andy Ying-Guey Fuh 

机构地区：[1]Department of Physics, National Cheng Kung University, Tainan, Taiwan [2]Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan [3]Department of Photonics, National Cheng Kung University, Tainan, Taiwan [4]Advanced Optoelectronic Technology Center, National Cheng Kung University, Tainan, Taiwan

出　　处：《Optics and Photonics Journal》2014年第10期288-295,共8页光学与光子学期刊（英文）

摘　　要：We investigated optically controllable gray-level diffraction from a body-centered tetragonal photonic crystal that was based on an azo-dye-doped holographic polymer dispersed liquid crystal. The sample is fabricated by use of two-beam interference with multi-exposure. Bichromatic pumping beams at various intensities were used to pump the sample to change the concentration of the cis isomer and, in turn, modulate the effective index of the photonic crystals as well as their diffraction intensity. Three pumping processes were utilized to produce gray-level switching of diffractive light. This study demonstrates the optimum gray-level to be 15-level of up-step and down-step. The simulation of the diffraction intensity under bichromatic pumping sources was also studied.We investigated optically controllable gray-level diffraction from a body-centered tetragonal photonic crystal that was based on an azo-dye-doped holographic polymer dispersed liquid crystal. The sample is fabricated by use of two-beam interference with multi-exposure. Bichromatic pumping beams at various intensities were used to pump the sample to change the concentration of the cis isomer and, in turn, modulate the effective index of the photonic crystals as well as their diffraction intensity. Three pumping processes were utilized to produce gray-level switching of diffractive light. This study demonstrates the optimum gray-level to be 15-level of up-step and down-step. The simulation of the diffraction intensity under bichromatic pumping sources was also studied.

关 键 词：All Optically Control Gray-Level Photonic CRYSTALS HPDLC 

分 类 号：R73[医药卫生—肿瘤]