| 摘要 |
PURPOSE:To decrease the minimum reading value and thus realize the high-accuracy measurement of the light beam position by providing the photo detector to the slider having the vernier scale. CONSTITUTION:Main scales 16a and 16b are provided to measuring device main body 17 with the base points separated into the upper and lower sides, and slider 13 is installed to the side of main body 17 in the free up-down movement way. At the same time, vernier scale 13b is provided to the edge of slider 13 opposing to scales 16a and 16b. And photo detectors 14a and 14b of up-down two steps are installed to the slit in front of main body 17 to be fixed to slider 13. Thus lamps 15a- 15c installed to the side of slider 13 are lit up selectively according to the intensity of the laser beam detected by each photo detector. At the measuring time, slider 13 is slided in accordance with the glowing state of each lamp 15. And thus the position is measured for the laser beam based on the readings of scales 16a, 16b and 13b each when lamps 15 are glowing. |
