| 摘要 |
PURPOSE:To shorten a position adjustment time by comparing the intensity of light on a photodetecting element, etc., between an optical modulator which is not positioned accurately and an optical modulator which is positioned accurately when reflected light from a mark is made incident on the photodetecting element. CONSTITUTION:A lamp is turned on continuously to irradiate the reflective mark 51 on the optical modulator 27 with light from the lamp, reflected light from the mark 51 is incident on one of photodetection surfaces; and the 1st fitting plate 61 is moved in an axial direction of a shaft 64 to the position of the output of the incident light is maximum and a screw 67 is fixed to the shaft 64 lightly. Then, a screw 69 is moved forth and back about a temporary position and fixed where the output of the photodetection surface at the center position is maximum; and the screw 67 is moved forth to the shaft 64 to fix the fitting plate 61 so that the plate does not swing on the shaft 64. Thus, the position adjustment time is shortened. |
