Radiant energy – Photocells; circuits and apparatus – Photocell controls its own optical systems
Patent
1989-10-24
1990-10-16
Nelms, David C.
Radiant energy
Photocells; circuits and apparatus
Photocell controls its own optical systems
350163, G01J 120
Patent
active
049637258
ABSTRACT:
An adaptive optical network is provided for the implementation of learning algorithms. The network comprises a double Mach-Zehnder interferometer in conjunction with a photorefractive crystal that functions as a holographic medium. Light from selectable sources on opposite sides of a beamsplitter is passed through the interferometer, at least one arm of which includes a spatial light modulator for imprinting a data pattern on the light. The light is directed into the holographic medium to develop a refractive index grating corresponding to the data pattern. Light from the hologram is sensed by a photodetector that provides a signal to a threshold device. The output of the threshold device is compared with a reference signal to produce an error signal that can be used to select the source of light directed through the network. The interconnections of the optical devices function to compute the inner product between the elements of the data pattern and their weight factors. Selecting the light source and changing the data pattern provide additive and subtractive weight change capability for implementing various learning algorithms.
REFERENCES:
patent: 4025195 (1977-05-01), Ebersole et al.
patent: 4124278 (1978-11-01), Grinberg
patent: 4372649 (1983-02-01), Kellie
patent: 4718749 (1988-01-01), Chiou et al.
Y. S. Abu-Mostafa et al., "Optical Neural Computers", Scientific American, Mar. 1987, pp. 88-95.
P. Yeh et al., "Real-Time Optical Image Substraction Using Dynamic Holographic Interference in Photorefractive Media" Optics Letters, vol. 13, No. 7, pp. 586-588 (Jul. 1988).
D. Psaltis et al., "Adaptive Optical Networks Using Photorefractive Crystals", Applied Optics, vol. 27, No. 9, pp. 1752-1759 (May 1, 1988).
Hong John H.
Yeh Pochi A.
Allen Stephone B.
Hamann H. Fredrick
McFarren John C.
Nelms David C.
Rockwell International Corporation
LandOfFree
Adaptive optical neural network does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Adaptive optical neural network, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Adaptive optical neural network will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-851052