| 摘要 |
PURPOSE:To improve measuring accuracy, by computing a light receiving region based on the result of the detection of received light of one bit of a specified light receiving element in the light receiving region of an image sensor. CONSTITUTION:Laser light beam 2 projected from a light source 2 is applied on a material to be measured 3, and reflected light 2' is received by a lens 5. At this time, a light receiving element is arranged so that the locus of an optical spot image is aligned in approximately parallel with the light receiving surface of an image sensor 6 in a camera 4. The video signal from the sensor 6 is supplied to a light-receiving-region detection device 8 and an operating device 9 through an amplifier 7. Both ends of the light receiving region of the sensor 6 and the presence or absence of the received light of one bit of the light receiving elements before and after the region are detected. Based on the detected result, the averaged light receiving region is computed. |
