| 摘要 |
A multiple working range scanner includes a collection mirror which is segmented, with each segment having differing optical properties, such as focal length, optical axis, and so on. Differing segments or combinations of segments deal with reflected light received at differing working ranges, and direct it to a photodetector. In another embodiment, beam shaping may be applied to an astigmatic laser beam, for example by means of a part-concave mirror, to create an x waist in the beam which is further from the scanner than the y waist. This provides enhanced performance when the scanner is used on a bar code symbol which is not accurately aligned. In order to provide improved optical alignment within a bar code scanner, the collection mirror may be adjustable both in the x direction and in the y direction.
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