| 摘要 |
PURPOSE:To reduce the nonuniformity of scanning caused by the falling-down of planes and the generation of vibrations or noise caused by the imbalanced shape or air pressure by providing a concentric arc-shaped plane between two reflecting mirror planes faced each other with a rotating core as a center. CONSTITUTION:A rotary mirror 100 forms only two reflecting mirror planes 101 and 102 by cutting two faced positions into planes with the rotating core as the center on the outer peripheral face of an aluminium base equipped with the cylindrical outer peripheral face. Therefore, even assuming that there is plane falling-down error between the first and second planes of the two reflecting mirror planes 101 and 102, the pitch of black or white is always fixed and image nonuniformity is not generated since the back and black or the white and white are printed by deflection depending on the same plane totally. Since a surface connecting the two reflecting mirror planes 101 and 102 of the rotary mirror 100 is concentrically arc-shaped, the influence of the imbalanced shape or the air pressure and the generation of turbulence are reduced, and the adverse influence generated in the case of high-speed rotation can be reduced as well. |
