| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain an optically coupled device which is capable of carrying out position detection with high accuracy by a method wherein a stable output is obtained from a photodetector independent of an output variation in a light emitting device. SOLUTION: A light emitting device 1 and a photodetecting device 20 are arranged facing to each other having a path 11 therebetween, where a detected object H moves, wherein the photodetecting device 20 is composed of photodetectors 22a and 22b which are equally divided by the diagonal line 21 which is of the rectangular form of the detected object H in a plan view and obliquely crosses the movement axis G. The detectors 22a and 22b are changed in detected light volume with the movement of the detected object H. The detected light volume ratio of the detector 22a to the detector 22b is computed, and an output corresponding to a movement of the detected object H can be obtained.</p> |
