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Self Illuminating Scanner Array Incorporating a Limiting Aperture Made by a Plasma Spray Process

IP.com Disclosure Number: IPCOM000085890D
Original Publication Date: 1976-Jun-01
Included in the Prior Art Database: 2005-Mar-03
Document File: 2 page(s) / 46K

Publishing Venue

IBM

Related People

Baxter, DW: AUTHOR [+4]

Abstract

A self-illuminating optical scanning array is used to position a document with an accuracy of 5 mils. This is done using a scanner with 3 mil wide apertures positioned at 80 mil intervals. The document includes a series of targets which are positioned at 85 mil intervals. The targets are of a width which permits only one aperture to be covered at any one time. Using a sequence of 9 apertures in cooperation with a sequence of 9 targets, a document may be positioned over a 40 mil length at a resolution of 5 mils, as the apertures and targets function as an optical vernier with aperture one being covered by target one, followed by aperture two being covered by target two, etc.

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Self Illuminating Scanner Array Incorporating a Limiting Aperture Made by a Plasma Spray Process

A self-illuminating optical scanning array is used to position a document with an accuracy of 5 mils. This is done using a scanner with 3 mil wide apertures positioned at 80 mil intervals. The document includes a series of targets which are positioned at 85 mil intervals. The targets are of a width which permits only one aperture to be covered at any one time. Using a sequence of 9 apertures in cooperation with a sequence of 9 targets, a document may be positioned over a 40 mil length at a resolution of 5 mils, as the apertures and targets function as an optical vernier with aperture one being covered by target one, followed by aperture two being covered by target two, etc.

The aperture plate for this device must present the aperture in close proximity to the document. An intervening thickness of a protective glass, for example, would degrade scanner performance. The surface must additionally be abrasion resistant because documents, particularly paper, have abrasive qualities and the tendency for apertures to provide catch points for dust or other foreign particles should also be avoided.

The aperture plate 10 as shown in the figure, is formed of a glass plate on which the opaque surfaces 12 are formed by plasma flame spraying an opaque coating of a highly abrasion resistant material, such as alumina titania oxide, while masking the aperture portions 11. A coating hav...