All-optical implementation of the inverted neural network model

I. Shariv; T. Grossman; E. Domany; Asher A. Friesem

doi:10.1117/12.22127

1 July 1990 All-optical implementation of the inverted neural network model

I. Shariv, T. Grossman, E. Domany, Asher A. Friesem

Proceedings Volume 1319, Optics in Complex Systems; (1990) https://doi.org/10.1117/12.22127
Event: 15th International Optics in Complex Systems, 1990, Garmisch, Germany

Abstract

The Inverted Neural Network (INN) model especially designed for optical implementation is presented. This model takes into account the physical constraints imposed by conventional optical components and ensures that all the connections are positive. Thus subtraction of light intensities is not required for implementation nor are electronic computations. In the laboratory realization of the INN model a liquid crystal light valve fulfills the function of an array of neurons while an array of subholograxns serves as the interconnects. The overall network was tested with 64 neurons and four stable states. 1. INTRODTJCTION Several problems have to be solved in order to realize neural network models optically. The first problem stems from the fact that most models consist of both positive and negative interconnects. Conventional solutions to this problem usually involve electronic subtractions or dynamic threshold levels. It has been recently shown1''2 how the Hopfleld model can be modified into a model with positive values only. An all-optical realization of the modified model for 16 neurons and two stable states has also been demonstrated1 . The second problem that has to be considered is the fact that most of the optical devices that are used for realizing the neurons cannot exhibit very sharp thresholding. Although neurons with graded response have collective computational properties like those of two state neurons the memory capacity of Hopfield-type networks decreases as the slope of the neural

Citation Download Citation

I. Shariv, T. Grossman, E. Domany, and Asher A. Friesem "All-optical implementation of the inverted neural network model", Proc. SPIE 1319, Optics in Complex Systems, (1 July 1990); https://doi.org/10.1117/12.22127

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available