| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical scanner capable of reducing the number of light sources such that the number of light sources is less than the number of surfaces to be scanned without reducing stability of optical scanning. <P>SOLUTION: A light beam dividing member 2203 divides a light beam emitted from a light source into two light beams L1 and L2 spaced apart from each other with respect to a sub-scanning corresponding direction. As viewed from a Z axis direction, a four-surface mirror of a first stage and a four-surface mirror of a second stage of a polygon mirror rotate about the same rotational axis in such a manner that the four-surface mirrors of the first and second stages are shifted by relatively and approximately 45° from each other. A quarter wavelength plate Q1 is disposed on an optical path of the light beam L1 that travels toward the four-surface mirror of the second stage, and a quarter wavelength plate Q2 is disposed on an optical path of the light beam L2 that travels toward the four-surface mirror of the first stage. Further, the light beam L1 and the light beam L2 are made incident to the polygon mirror become two types of circularly polarized light that rotate in the same direction. Returned light of the light beam L1 is reflected by the light beam dividing member 2203, and returned light of the light beam L2 is transmitted through the light beam dividing member 2203. Neither the returned light of the light beam L1 nor the returned light of the light beam L2 travels toward the light source. <P>COPYRIGHT: (C)2013,JPO&INPIT |
