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Secure Document Feature for Copy Machines

IP.com Disclosure Number: IPCOM000077304D
Original Publication Date: 1972-Jul-01
Included in the Prior Art Database: 2005-Feb-25
Document File: 2 page(s) / 44K

Publishing Venue

IBM

Related People

Hobgood, GW: AUTHOR

Abstract

In order to render a copying machine inoperable to prevent copying of selected security documents, a technique of sensing the documents internally to the machine through an optical arrangement is described. The document 10 to be kept secret and not reproduced is laminated to a sheet of plane polarized material 12. The copying apparatus within a secure area is modified in that a light source 14 is mounted so that it will impinge light onto the document plane 16 and the document 10 on a copier. Placed between the light source 14 and the document plane 16 is a rotating disc plane polarized filter 18. The motor 20 which drives the filter 18 is set to rotate the filter 18 at a desired speed, omega.

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Secure Document Feature for Copy Machines

In order to render a copying machine inoperable to prevent copying of selected security documents, a technique of sensing the documents internally to the machine through an optical arrangement is described. The document 10 to be kept secret and not reproduced is laminated to a sheet of plane polarized material 12. The copying apparatus within a secure area is modified in that a light source 14 is mounted so that it will impinge light onto the document plane 16 and the document 10 on a copier. Placed between the light source 14 and the document plane 16 is a rotating disc plane polarized filter 18. The motor 20 which drives the filter 18 is set to rotate the filter 18 at a desired speed, omega. The light emanating from the light source 14 and passing through the rotating filter 18 is a bundle of plane polarized light, which has a rotating polarization vector. A light-sensitive detector cell 22 is mounted at an angle to receive this bundle of light with the rotating polarization vector, after it is transmitted through document plane 16 and reflected from secret document 10.

The light-sensitive detector cell 22 is connected to a frequency tuned amplifier 24 and an electronic detector 26, the copying machine is disabled by copier control 25 and will not function until it is reenabled either by a key operator or a Customer Engineer. The light detector 22 senses the reflected light coming from the document 10 with the laminated...