| 摘要 |
<p>Facsimile reproducing appts. uses laterally-aligned beams (la,Lb,Lc) the line of alignment being at a small angle (theta) to the direction of scan. This angle may be varied, thereby varying the line pitch (P), when a high resolution scan is required. The beams are scanned over the surface of a drum, the angle (theta) being controlled by passing the fixed b3ams through an optical rotator on the beam producing device e.g. a semiconductor laser chip - which may be physically rotated. The beams are modulated via respective delays to take account of the differing positions of the beams in the direction of scan.</p> |
