[OPTICAL REVIEW Vol. 2, No. 4 (1995) 255-260]

Optical Module for Modified Signed-Digit Computing Based on Bit Plane Encoding and Pattern Operations

Hongxin HUANG, Masahide ITOH and Toyohiko YATAGAI

Institute of Applied Physics, University of Tsukuba, Tsukuba, Ibaraki, 305 Japan

(Received January 19, 1995; Accepted April 26, 1995)

We propose here a new optical modified signed-digit (MSD) adder module based on bit plane pattern encoding of MSD digits and pattern operations. The pattern operations required in the algorithm are duplication, combination and shifting. They are simply performed by using optical components such as beam splitters, mirrors and parallel plates, instead of optical logic arrays. An optical MSD adder module comprised of six properly interacting blocks with all optical components packaged on a common substrate is presented in detail. We analyze the system errors caused by manufacture and alignment of optical components, the information throughput, the intensity nonuniformity and the system volume of the adder module.

Key words : modified signed-digit computing, bit plane encoding, parallel optical computing