Authors: SY Huang TC Wung A YG Fuh HC Yeh CY Huang CM Ma SC Huang TS Mo CR Lee
Publish Date: 2009/10/30
Volume: 97, Issue: 4, Pages: 749-
Abstract
This work presents an electro and photocontrollable spatial filter that is based on a liquid crystal LC film with a photoconductive layer The controllable spatial filter can be formed because of the controllability of the photoelectroinduced screen effect of the space charge in the LC cell An applied dc voltage or incident pumped intensity can be controlled to enable different spatial distributions of the diffraction pattern of the target object to be selected for filtering by the LC cell such that various reconstructed images can be obtained A simulation using Fourier analysis is developed and its results agree closely with experimental results Additionally the LC spatial filter has the extra advantage of controllable low or high filtering functions they are controlled by switching the configuration between normally black and normally white modes
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