Holographic-based digital optical processor for signal and data processing applications

This paper will review the results of an 18 month program which developed and demonstrated a compact size general purpose Holographic-Based Digital Optical Processor, HBDOP. The HBDOP was developed to accommodate a number of different holograms. Three Holograms were developed; one performs parallel symbolic substitution for hetero-associative memory recall, a second performs 64 node hypercube interconnection network operation, and the third performs 64 node mesh-interconnected multiprocessor operation. The 64 node hypercube interconnect operation will not be discussed in this paper. The demonstrated systems utilize N ** 4 holographic array recording to achieve massive interconnection parallelism not achievable with VLSI technology. Significant results of the program included the demonstration of 64 digital optical processors operating in parallel to perform digital operations such as morphological functions, simple target tracking, and noise removal operations using simple logic functions while simultaneously communicating through a mesh interconnection network. The demonstration of a 32 X 32 hologram array containing inter-pattern associations to act as an interconnection weight matrix for symbolic substitution and associative memory recall operations. The demonstration of a 64-node hypercube interconnection network by using the N ** 4 hologram array to achieve 3-D parallel interconnection. Finally, the development of an automatic system for N ** 4 holographic array recording. The automatic recording system is capable of recording one hologram element in 10 seconds.