Abstract

A submicron metal grid mirror was incorporated into the structure of a silicon liquid light valve. This polarization-sensitive mirror allows the use of the LCLV as a bistable device. In our experiment, a 0.5-µm period, aluminum wire grid mirror was used in conjunction with a 90° twisted nematic configuration. Theoretical analysis predicts a 5:1 peak-to-threshold level ratio of the output levels using a He-Ne beam. A sharp threshold with a peak-to-threshold ratio of 3:1 was experimentally observed. The threshold intensity level was tunable from 2.5 to 50 µW/cm² by changing the bias voltage from ~5 to 25 V. This tunability allows the device to be used as an adaptive image thresholder. The polarization-sensitive mirror allows the device to be used also as an interfacing device for an optical coprocessor as well as for optical implementation of Hopfield-Anderson association and for phase conjugation.

© 1989 Optical Society of America