| 摘要 |
<p>PURPOSE:To detect distances in a broad area at high distance resolution, by inputting lights from materials to be measured at a long distance and a short distance as light points into different light receiving area, and selecting the output of a photocurrent from the light receiving area, where the light is inputted most intensely. CONSTITUTION:In a plurality of light receiving areas 520-524 of a semiconductor position detector 5, into which lights are inputted from a materials to be measured, one of each pair of signal lead-out electrodes is aligned with others in neighboring positions. The intervals between the signal lead-out electrodes sequentially become large by equal time. Photocurrents for said each pair of the signal lead-out electrodes are sent to adding circuit U9-U13. When the incident light spot is deviated into the neighboring light receiving area, the decreased amount of the photocurrent is corrected. The outputs of adding circuit U10-U12 are imparted to sample holding circuits U18-U20 and further inputted into comparator circuits U24-U26. In which light receiving area the signal light reflected from the material to be measured hits most intensely is judged. Then, signals G1, G2 and G3 are outputted.</p> |
