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Interrogation of Optical Read Only Storage

IP.com Disclosure Number: IPCOM000092397D
Original Publication Date: 1967-Dec-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 2 page(s) / 25K

Publishing Venue

IBM

Related People

Weinberger, A: AUTHOR

Abstract

Separation of the word selection function in the interrogation of a read-only store from the light sources to the light detectors is performed in this system. This change obviates the need for switching a multiple number of light-emitting devices.

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Interrogation of Optical Read Only Storage

Separation of the word selection function in the interrogation of a read-only store from the light sources to the light detectors is performed in this system. This change obviates the need for switching a multiple number of light-emitting devices.

Conventional readout systems for optical read-only stores include a matrix of light emitters of which one word at a time is selected, a corresponding matrix of light detectors, and an information mask located between the matrices. The mask contains the information bit pattern in the form of opaque and transparent areas.

This system employs constant light source 1 providing light beam 2 which interrogates the information bearing mask 3. Dependent on the bit pattern on mask 3, light beams 5 impinge on corresponding light detectors of matrix 4. A matrix of logic circuits 7 including one logic gate for each light detector controls the selection of a word for interrogation at the light detectors. As logic circuits 7 activate one word line at a time, the corresponding light detector outputs are selected to enter output circuit 6. The output in circuit 6 is indicative of the bit pattern of the selected word. This arrangement enables the light detectors' logic circuits and output circuits to be constructed in a single monolithic package.

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