Automatic focusing system for imaging-based bar code reader

Details Automatic focusing system for imaging-based bar code reader Automatic focusing system for imaging-based bar code reader

2007-12-04

2007-12-04

Lee, Seung Ho (Department: 2876)

Registers

Coded record sensors

Particular sensor structure

C235S462200, C235S462230, C235S462240, C235S462410

Reexamination Certificate

active

10903792

ABSTRACT:
An automatic focusing system for an imaging-based bar code reader. The automatic focusing system employs a two step process for moving a lens of an imaging system along its path of travel such that a sharp image of a target bar code is projected or focused onto an imaging system pixel array. The first step is laser ranging which utilizes a laser beam for range finding. Laser ranging determines a distance between the imaging system pixel array and the target bar code. Given the determined distance, the automatic focusing system moves the lens to a suitable position for imaging the target bar code. If ambient conditions prevent laser ranging from properly working, the second step is focus analysis. Focus analysis involves moving the lens in accordance with a search routine and analyzing image frames of the target object to find a suitable focus position.

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