High-speed optically-addressed spatial light modulator

Author

Li, Wenyuan ; Kuo, C.T. ; Moddel, Garret

Author_Institution

Dept. of Electr. & Comput. Eng., Colorado Univ., Boulder, CO

Volume

35

Issue

12

fYear

1988

fDate

12/1/1988 12:00:00 AM

Firstpage

2447

Lastpage

2448

Abstract

High-speed optically-addressed spatial light modulators (OASLMs) have been designed, fabricated, and tested. The response time of these devices, in which a ferroelectric liquid-crystal (FLC) is incorporated as the modulating layer, can be substantially faster than that of OASLMs using nematic liquid crystals. A p-i-n structure of hydrogenated amorphous silicon (a-Si:H), which forms the photosensor, has response times, resolution, and mechanical properties that are compatible with the FLC. Two ranges of response times to write beam illumination, below and above approximately 100 ms, have been observed in the OASLM devices. The longer times appear to result from the photoconductivity of the highly resistive i-layer of the photodiode. Under chopped illumination the photoconductivity is averaged out, so that the photocurrent produced during the negative bias segment of the cycle produces the shorter response time optical modulation

Keywords

integrated optoelectronics; liquid crystal devices; optical modulation; photodetectors; 100 ms; amorphous Si:H; ferroelectric liquid-crystal; high speed operation; highly resistive i-layer; optically-addressed; p-i-n structure; photoconductivity; photodiode; photosensor; response time; spatial light modulator; Delay; Ferroelectric materials; High speed optical techniques; Lighting; Liquid crystal devices; Liquid crystals; Optical design; Optical modulation; Photoconductivity; Testing;

fLanguage

English

Journal_Title

Electron Devices, IEEE Transactions on

Publisher

ieee

ISSN

0018-9383

Type

jour

DOI

10.1109/16.8875

Filename

8875