Abstract

Optically bistable nonlinear interference filter (NLEF) structures have been used as logic, memory or threshold devices in the field of digital optical computing. They operate via a temperature dependent refractive index change of the spacer [1]. Materials such as ZnSe and ZnS are commonly used as the nonlinear medium because of the magnitude of their dn/dT (~1x10^-4K^-1), and their ease of deposition [2]. Optical and thermal characteristics of such a device are critical factors if acceptable operating conditions are to be achieved [3,4]. For any parallel processing to be demonstrated large arrays of 2-dimensional binary data channels in the form of spatially separated pixels must be operated simultaneously on the device plane, so necessitating both high degrees of uniformity, and also low levels of cross talk [5]. A specific application demanding these properties is as the logic plane within a currently operating demonstrator; the Optical Cellular Logic Image Proccessor (O-CLIP) [6].

© 1992 Optical Society of America