05831254 is referenced by 219 patents and cites 25 patents.

An exposure control apparatus for use with optical readers, such as bar code readers, which utilize photosensitive image sensors. An illumination signal generating circuit generates an illumination signal having a magnitude that varies in accordance with the time averaged value of the illumination level at the image sensor. A window detecting circuit periodically samples the illumination signal to determine if that signal is or is not within a window of acceptability. Exposure period determining circuitry uses the output of the window detecting circuit to upwardly or downwardly adjust the value of a control variable as necessary to cause the illumination signal to approach, enter and remain within the window of acceptability.

Title
Exposure control apparatus for use with optical readers
Application Number
8/574386
Publication Number
5831254
Application Date
December 18, 1995
Publication Date
November 3, 1998
Inventor
John A Pettinelli
Rome
NY, US
Robert C Gardiner
Liverpool
NY, US
Dennis W McEnery
Marcellus
NY, US
Thomas W Karpen
Skaneateles
NY, US
Agent
Wall Marjama Bilinski & Burr
Assignee
Welch Allyn
NY, US
IPC
G06K 7/10
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