Browse Prior Art Database

Scanning Lens

IP.com Disclosure Number: IPCOM000076660D
Original Publication Date: 1972-Apr-01
Included in the Prior Art Database: 2005-Feb-24
Document File: 2 page(s) / 41K

Publishing Venue

IBM

Related People

Tibbetts, RE: AUTHOR [+2]

Abstract

A six-element scanning lens, as shown in Fig. 1 is provided for optical character recognition applications. Scanning is accomplished, as shown in Fig. 2, by pivoting a mirror, thus allowing scanning of the desired area with light passing through the scanning lens in both directions. Because of the unusual light passage, the lens of Fig. 1 has its lens axis matched against its field rather than matching axis-to-axis or field-to-field as is the usual procedure. As a result, the lens is well corrected over its total angular field with respect to the scanning mirror, which is its external aperture stop.

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Scanning Lens

A six-element scanning lens, as shown in Fig. 1 is provided for optical character recognition applications. Scanning is accomplished, as shown in Fig. 2, by pivoting a mirror, thus allowing scanning of the desired area with light passing through the scanning lens in both directions. Because of the unusual light passage, the lens of Fig. 1 has its lens axis matched against its field rather than matching axis-to-axis or field-to-field as is the usual procedure. As a result, the lens is well corrected over its total angular field with respect to the scanning mirror, which is its external aperture stop.

The lens is f/10 with an effective focal length of 379.93 millimeters. Embodiments of the lens may be constructed within the ranges of constructional data set forth below, wherein R is the radium of curvature, t is the thickness of the lens element at the center, and s is the airspace along the central axis. .20f < + R(1) < .22f .023f < t(1) < .027f .30f < - R(2) < .32f .011f < t(2) <
.015f .14f < + R(3) < .15f .004f < s(1) < .010f .15f < + R(4) < .17f
.013f < t(3) < .017f .19f < + R(5) < .21f .017f < s(2) < .021f .22f < - R(6) <
.24f .013f < t(4) < .017f .15f < - R(7) < .17f .006f < s(3) < .007f
.11f < - R(8) < .13f .011f < t(5) < .015f .81f < - R(9) < .91f .024f < t(6) < .028f .15f < - R(10)< .16f.

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