Abstract

In this work, the polarization-encoded optical shadow-casting (POSC) algorithm for designing a parallel multiprocessor is described. As an example, we have used the POSC algorithm to design a combined adder-subtracter. Unlike the all-electronic digital adder/subtracters, this multiprocessor provides the outputs of both addition and subtraction simultaneously without any increase in the system hardware.¹ This multiprocessor is the first of its kind reported in the optical computing literature. Further, this design points out an important distinction of optical digital system design as follows: In digital systems, the number of gate inputs as well as the number of gates are reduced by using a Karnaugh map.² But in the optical shadowcasting scheme, the simplification of the logic circuit is achieved by the sharing of minterms.¹ In digital electronics, such minterm sharing is usually not attempted. The design of this parallel multiple-output dual-addressable multiprocessor memory device is very attractive as it saves memory by 50% or more. The proposed device gives out parallel output bits and is highly efficient when compared with its electronic counterpart.

© 1989 Optical Society of America