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Optical Sensing for Punched Cards

IP.com Disclosure Number: IPCOM000096196D
Original Publication Date: 1963-Jan-01
Included in the Prior Art Database: 2005-Mar-07
Document File: 2 page(s) / 59K

Publishing Venue

IBM

Related People

Raviart, C: AUTHOR

Abstract

In this optical sensing device, no electrical signals pass through movable elements.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 74% of the total text.

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Optical Sensing for Punched Cards

In this optical sensing device, no electrical signals pass through movable elements.

Light source S, a lens L and screens E, form a very thin parallel beam F. This is reflected by rotating mirror M and forms light beam FR'1. Another mirror M1 reflects the beam once again (FR''1) to sensing cells R. Their number is equal to that of the card lines. Card C acts as a screen and does not allow the light of beam FR''1 to pass except through the holes of column C1. At the next sensing time, mirror M is revolved into M' position. Beam F is reflected in the direction FR'2 to the mirror M2. This other fixed mirror reflects the beam in the direction FR''2 to the same cells R. Now, the second card column C2 is in the path of beam FR''2 and is read. Mirror M continues to turn and beam F is then reflected by M to a third fixed mirror. This always reflects it to the same sensing cells R. At this time, the reflected beam is interrupted by the third card column which is read.

The exploration of the card continues in this way with the rotation of mirror M and the beam reflection on successive mirrors M1...Mn, where n is the number of card columns.

Reading is effected at a constant speed. Mirrors M1... Mn must be set on such a curve so that, after the second reflection, the beam is sent to the same sensing cells R and is intercepted by the successive card columns. The successively arranged mirrors M1... Mn are hit by the beam by rotating the mirror...