Accession Number:

ADA230661

Title:

A Compact Optical Associative Memory Using Dynamic Holographic Storage Media and Photorefractive Gain and Attenuation Elements

Descriptive Note:

Master's thesis

Corporate Author:

AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH

Personal Author(s):

Report Date:

1990-12-01

Pagination or Media Count:

185.0

Abstract:

This research effort implemented a compact optical associative memory architecture consisting of a Fabry-Perot Confocal Resonator FPCR optical processing environment, two dynamically reprogrammable Lithium Niobate volume holograms, and Barium Titanate gain and attenuation elements. The reduced physical dimensions of the compact optical processing environment make it more adaptable to military applications than previous associative memory designs. The FPCR employs Mangin mirrors designed to reduce spherical aberrations in off-axis rays. The orientation of the gain elements grating vector angle and the model used to predict the profile of the attenuation element were unique to this research effort. The object stored in the associative memory was phase encoded using a glass microscope slide etched in a 40 hydrofluoric acid solution. Beam path deviations caused by the non-parallel geometry of the photorefractive crystals were corrected with a variable pitch, plate glass optical wedge inserted in the cavitys feedback arm. Experimental results showed the system is capable of storing and fully retrieving a single object from memory when presented with partial information about the object Additional system modifications are required to store and retrieve multiple objects. Theses.

Subject Categories:

  • Optics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE