Optical scanner reflecting and outputting light increased in width and image forming apparatus using same

摘要

An optical scanner is disclosed which includes: a reflective surface from which incoming light is reflected; and a scanning sub-system altering an angle of the reflective surface, relative to an entry direction in which the incoming light enters the reflective surface, to thereby perform a scanning operation of reflected light from the reflective surface. The reflective surface is illuminated with illuminating light for the scanning operation, such that the illuminating light is so dimensioned in transverse cross-section as to together generate a desired segment of light entering the reflective surface and an undesired segment of light not entering the reflective surface.