Characterization of an analog ferroelectric spatial light modulator -: Application to dynamic diffractive optical elements and optical information processing

Spatial light Modulators (SLM) are key devices for the development of optical information processors. Low cost twisted nematic liquid crystal (TN-LC) SLM's are widely available and their characteristics have been extensively studied. Beside the fact that they exhibit a coupled amplitude and phase modulation, their speed is limited to approximately the video frame rate. An alternative to TN-LC devices can be the use of analog ferroelectric liquid crystal (FLC) devices. These devices now commercially available produce a gray level pure amplitude modulation at typical frame rates of I kHz. In order to determine its coding capabilities and its limitations, the characterization of such a device, manufactured by Boulder Nonlinear Systems Inc., is presented in this paper. This SLM has a resolution of 512 by 512 pixels with a pitch of 15 Pm and has a reflective VLSI backplane. The study of its potential applications for the display of dynamic diffractive optical elements and also as a component of an optical processor for pattern recognition will be followed by experimental results and comparisons with TN-LC devices.