MEASURING DEVICE OF SHAPE IN OPTICAL CUTTING METHOD

摘要

PURPOSE:To eliminate the influence of the reflected and scattered light in an optical cutting method and to improve considerably S/N and measuring accuracy by moving stepwise the spot light irradiated to an object to be measured, and matching the position of scanning lines started by an image pickup device and the irradiating point of the spot light. CONSTITUTION:A detecting light projector 3 is provided with an optical unit 5 and a freely rotatably provided reflection mirror 6. The mirror 6 is so arranged as to be turned at a required angle by a driving motor 7. A timing generating circuit which synchronizes the start of the scanning line of an image pickup device 8 and the driving of a driving motor 7 is connected to the device 3 and the device 8. The motor 7 turns stepwise the mirror 6 and the distance at which the irradiating point 11 of the detecting light moves by one step is made equal to the space between scanning lines on the image pickup screen. If the mirror 6 is moved stepwise in synchronization with the movement of the scanning lines in a way that the position of the irradiating point and the position of the scanning lines coincide with each other, the image obtd. by the device 8 is equal to the image obtd. by projecting the plate-shaped slit light as the detecting light.