| 摘要 |
PURPOSE:To reduce the variance of the reflecting point of a rotary polygon mirror and the variance of the polarized light scanning angle of each mirror surface by putting the polygon mirror on a motor shaft positioned to the adjacent surface section of the mirror after forming knurls on the external surface of the motor shaft and thermally deforming the shaft. CONSTITUTION:Knurled sections 4 are provided intermittently in the circumferential direction of a motor shaft in the section to which a rotating polygon mirror 3 is fitted on the upper surface of the shaft 2 protruding from a motor 1. When the mirror 3 is heated to about 80 deg.C, the inside diameter of the mirror 3 becomes larger than the diameter of the knurled section of the shaft 2 and the mirror 3 can be put on the shaft 2. It can be considered that the mirror 3 is shrinkage fitted to the shaft 2 when the temperatures of the shaft 2 and mirror 3 becomes equal to each other thereafter. When the motor 1 is operated at a fixed speed under such condition, the polarization scanning angle of each surface of the mirror 3 comes to nearly equal to another. |
