High-speed binary optically addressed spatial light modulator

Abstract

We describe the structure and operating characteristics of a high-speed optically addressed spatial light modulator (OASLM) with a hydrogenated amorphous silicon (a-Si:H) photosensor and a ferroelectric liquid-crystal modulator. The photosensor is a p-i-n photodiode, which switches the liquid crystal into one of two stable states. Under a write-light intensity of 6 mW/cm2, the OASLM exhibits a response time of 155 μs, a contrast ratio of 20:1, and a resolution of 40 lp/mm. The writing sensitivity per pixel is 0.1 pJ.