| 摘要 |
<p>A plurality of converging light beams (20) are focused on the same area of an optical recording medium (40) to sequentially scan data recorded on the medium. A plurality of detectors (22), one associated with each light beam (20), detect the scanned data and provide an output signal (A to D). A logic gate (50) receives the outputs from each of the plurality of detectors (22) and provides an output only when each detector (22) is sensing data so as to eliminate the effects of random surface irregularities (45) (e.g. dust particles) which may be in the beam path of one or more, but not all, of the light beams (20).</p> |
