POLYGON MIRROR

• Main Authors: SHICHIRI MASATAKA, KABEUCHI TERUO, MUKONO KATSUHIKO
• Format: Patent
• Language: English
• Published: 24.05.1990
• Subjects: OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PHYSICS

PURPOSE:To compensate the distortion of the mirror surface of a polygon mirror and to improve the resolution of the mirror when the mirror is rotated at high speed by forming through holes parallel to the rotary axis of the mirror at middle sections between the edge of each mirror surface and the rotary axis. CONSTITUTION:This polygon mirror 2 has a regular hexagonal body constituted of six Al platy bodies 2A with mirror surfaces 2a on one sides and the center of the mirror 2 is coupled with a rotary shaft on which the mirror 2 rotates at high speed. Through holes 5 are provided in parallel with the rotary axis at middle sections between the edge 9 of each mirror surface 2a and the rotary axis so that the holes 5 can prevent distortion of the mirror surfaces 2a produced when the mirror 2 is rotated at the high speed. In addition, thin hexagonal cover members 6 which cover entire side faces of the mirrors 2a are integrally provided on the left and right sides of the mirror 2. In order to eliminate the aerodynamic noise produced by the holes 5 when the mirror 2 is rotated at high speed, the cover members 6 overlap the side faces of the mirror 2 so as to completely cover the holes 5.