| 摘要 |
In an exemplary embodiment, a hand-hald bar code reader has an elongated relatively narrow hand grip portion and an enlarged reader head portion with an extended window of greater width that the hand grip portion. Light energy is outwardly through the extended window so as to flood a bar code sensing region in front of the window having a depth dimension of at least about ten millimeters, and an optical system focuses bar code patterns in the sensing region onto an image plane in the reader unit with a resolution so as to read bars/spaces with a minimum width of about 0.0075 inch, or even less. Preferably the lens system provides a depth of focus for such bar code patterns of at least ten millimeters, so that a bar code pattern of marked curvature can be read in its entirety by means of an instant reading operation.
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