OPTOELECTRONIC DATA FILTER FOR SELECTION AND PROJECTION

Database processing, like the majority of nonnumerical applications, e xhibits a high degree of functional parallelism but does not require c omplex operations; therefore it is amenable to optical solutions. The architecture of an optoelectronic filter that is capable of performing selection and projection operations on a two-dimensional data array i n a relational database environment is presented. The system receives input from a parallel optical memory, one page at a time, and performs logic operations by using optoelectronic smart pixels based on hetero structure phototransistors and vertical-cavity surface-emitting lasers . Combinations Of AND and XOR gates are used to realize row-column mas king and comparisons of input data against user-supplied search argume nts. The main goal of the filter is to reduce the effective data rate between the highly parallel optical storage and the low input data rat e conventional electronic computer, thus efficiently interfacing curre ntly available photonic and electronic technologies.