04877949 is referenced by 340 patents and cites 13 patents.

In the instant reading of bar codes by flash illumination, the disclosed system automatically adapts to bar code configurations of greater extent and/or curvature, for example by measuring distance to one or more points on the bar code and adjusting a lens barrel, and/or by selecting from multiple image paths through a lens system. Plural illumination sources may be used to enhance the uniformity of the reflected bar code image, may be flashed jointly and/or in rapid sequence, and may have flash durations individually adapted to respective segments of a bar code for optimum sensitivity and signal to noise ratio. One or a plurality of reflected light sensors may control integration time of a bar code image sensor, for example during sequential activation of plural illumination sources. Marker light beams may originate in the vicinity of the bar code image sensor and be projected through the optics to produce light spots on the bar code label precisely delineating the image sensor field of view.

Title
Hand-held instant bar code reader system with automated focus based on distance measurements
Application Number
6/894689
Publication Number
4877949
Application Date
August 8, 1986
Publication Date
October 31, 1989
Inventor
Dennis A Durbin
Cedar Rapids
IA, US
Arvin D Danielson
Cedar Rapids
IA, US
Agent
Neuman Williams Anderson & Olson
Assignee
Norand Corporation
IA, US
IPC
G06K 7/10
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