| 摘要 |
PURPOSE:To make visual inspection and length measurement of an object to be detected at the same time by irradiating the object to be detected with laser light and photodetecting its reflected light or transmitted light with a photodetecting element and integrating its photodetecting output in flying spot system measurement. CONSTITUTION:The laser light is made a parallel scanning beam and irradiated the object to be detected and the reflected light is photodetected with a photoelectric conversion element and converted photoelectrically. Its signal is amplified with an amplifier 9 and inputted to a comparator 11 and compared with the reference voltage V1. When the output of the amplifier 9 is lower than the reference voltage V1, a rectangular wave pulse is outputted. Then, a signal from the comparator 11 is integrated with an integrator 12 and inputted to a sample and hold circuit 13. On the other hand, since the laser light irradiates with the specified frequency and the specified amplitude, the length of the object to the detected is proportioned to the output voltage V of the integrator 13. Further, an output signal of the amplifier 9 is impressed to a comparator 20 and compared with a set level for flaw detection. Consequently, since the output of the photodetecting element is integrated, the length of the object to be detected is measured and the visual inspection can be made at the same time. |
