Abstract

We have investigated two novel techniques for the realization of smart SLMs in silicon. In this paper we discuss an array of electrostatically driven tortional mirror micro-machines. Since these devices are fabricated in silicon, it is natural to integrate photodetectors and processing electronics with the mirror arrays. In the simplest such smart SLM the deflection of each mirror is determined by the intensity of the light incident on an associated photodetector. In more sophisticated designs neighboring pixels may be connected through simple processing electronics to produce mirror deflections in response to local image characteristics such as gradients or averages. This class of device will find application in many areas of optical processing including optical interconnects, optical switching, optical image analysis, and optical neural networks. We will discuss the fabrication of mirror arrays and the electrode strips that are used to actuate them. It is expected that two-dimensional arrays with pixels of 50 μm × 50 μm can be easily fabricated and will yield operating frequencies up to a few kilohertz; however, the results presented here concern the fabrication of eight-element, one-dimensional devices with pixels of 50 μm × 750 μm. The resonant frequency and deflection vs. applied voltage of the fabricated devices are measured and compared with theoretical predictions.

© 1992 Optical Society of America