| 摘要 |
A method of and a system (10) for generating scan lines having different beam characteristics. In one embodiment, the beam (16) is focused at different distances depending upon the scan line. The system (10) may comprise a light source (12) generating a reading beam (16), a suitable scanning mechanism such as a polygon mirror having a plurality of mirror facets (22, 24, 26, 28), a beam correction plate (30) in the beam path mounted to the facet wheel (20) and rotating therewith. The reading beam (16) passes through the correction plate (30) and is then reflected off the mirror facet (26), the correction plate (30) adjusting a beam characteristic, such as beam focus, scan angle, or beam power, for each mirror facet or portion of a mirror facet.
|
