| 摘要 |
PURPOSE:To obtain easily the laser beam diameter on the laser beam scanning surface, by putting the laser beam to be measured into the mobile reflecting plate having the prescribed grid pattern and then detecting the volume of the reflected light. CONSTITUTION:The mobile board 21 is attached to the support board 20 having an aperture part, and the grid 22 having a pitch larger enough than the diameter of the laser beam is held on the board 21. The beam 6 to be measured is incident to the grid 22 through the aperture part of the support frame 20, and the reflected light is detected by the photodetector 23 attached obliquely at the aperture part of the frame 20. In case this measuring device is used in the scanning optical system, the grid 22 is pressed to the cylinder roller 25 for measurement. The board 21 can be shifted in a minute amount by the sending screw 24. In this instant, the maximum and minimum values of the reflected light volume plus the light volume in case the entire surface of the grid is the transmission part are measured to obtain the beam diameter in an easy way. |
