| 摘要 |
PURPOSE:To permit determination of the absolute position of a processing head only by the slight movement of moving mirrors by providing the moving mirrors to the bent part in a laser optical path and to the front of a condenser lens of a processing head and a laser interference range finder to the rear of a laser oscillator. CONSTITUTION:The laser oscillator 1 is single-oscillated as stably as possible with a low output and the moving mirror 6 and the moving mirror 9 are directed to a distance measuring position (direction of a broken line in the figure) when the distance measurement of the absolute position is to be carried out. The output from the oscillator 1 passes beam splitters 2, 3, and a Y-axis beam guide 5, is reflected by the moving mirror 6, is passed through the splitter 3 and is entered as reflected light 14 to the laser interference range finder 14. Since a reference light 13 split by the splitter 2 enters the range finder 4, the optical path difference is determined from the two interference patterns of the light and the distance between the range finder 4 and the moving mirror 6 is measured. Only the moving mirror 6 is then moved and the distance between the meter 14 and the mirror 9 is measured. Since the position relation of the mirror 9 and the head 11 is known, the absolute position of the head 11 is determined. |
