| 摘要 |
PROBLEM TO BE SOLVED: To distribute only either reflected light or transmitted light separated by a reflecting mirror consisting of a half mirror to a body to be scanned and to prevent the other from influencing the body to be scanned as stray light. SOLUTION: A distance (a) between the incident position P of a laser beam L and an end 114 on an incident surface 111 is made smaller than 2t×tanθ1. After the light beam reflected on a back surface 112 or an end face 113c out of the transmitted light beam Lb is reflected on the end face 113 or 113a or the back surface 112, it becomes the light beam Le or Le' transmitted through the incident surface 111 in parallel with the laser beam L from the inside to the outside or the light Lf or Lf transmitted through the end faces 113 and 113a or 113c in a direction different from the reflected light La, and no light beam goes toward the surface of a photoreceptor drum 9 and a noise image by the light other than the reflected light La is not formed on the surface of the drum 9.
|
