| 摘要 |
<p>PURPOSE:To exactly detect a distance to an object to be ranged, by use of a simple device, by forming 2 photodetecting areas on a semiconductor substrate, and inputting an output from these photodetecting areas to a processing circuit. CONSTITUTION:The first (p) diffusion area 7b of a photodetecting element 7 is connected to the first photometric circuit 27 through an electrode 7e, and a (p) diffusion area 7c is connected to the second photometric circuit 28 through an electrode 7f. An electrode 7g direct-coupled with an (n) semiconductor substrate 7a is connected to the other input of the first and second photometric circuits 27, 28. A light beam from a light emission diode 24 is projected to an object to be ranged, through a lens 23, and a reflected ray from the object to be ranged is photodetected by a photodetector 7. Outputs of the first and second photometric circuits 27, 28 are inputted to a discriminating circuit DIS through logarithmic converting circuits 29, 30, operational amplifiers 31-34, etc., and a distance to the object to be ranged is detected.</p> |
