| 摘要 |
PURPOSE:To obtain a low-cost instrument with a simple circuit structure and a high noise resistance by providing an optical fiber bundle for transmitting a light beam to a detecting head unit and for irradiating an object to be measured and two optical fiber bundles for receiving reflected light from the object and for transmitting the received reflected light to a processing unit. CONSTITUTION:A projecting optical fiber bundle 15 transmits a light beam L1 to a detecting head unit H and irradiates an object 4 to be measured. Light receiving optical fiber bundles 16 and 17 receive the reflected light L2 and L3 of the light beam L1 and transmit the received light to a processing unit M. The positions of the optical fiber bundles 15 and 16 are set so as to correspond to desired displacement detecting positions by using an adjust screw 19. Thus, the end faces of the optical fiber bundles 16 and 17 are irradiated with the reflected light L3, which forms light spots on the end faces and is transmitted to the processing unit M via the optical fiber bundles 16 and 17 to be inputted to photodetectors 20 and 21, respectively. When the light spots of the reflected light L3 move to the positions of the optical fiber bundles 16 and 17 adjusted in advance, the output of a comparator 24 is inverted and it is detected that the object 4 to be measured moves to a prescribed position. Since the detecting head unit H outputs no electric signal at this time, noise resistance is improved. |
