| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical scanner configured to optically scan a single scanning target surface by a plurality of light beams, the optical scanner capable of reducing variation of a beam spot interval, and an image formation device. <P>SOLUTION: An optical scanner comprises at least one light source for emitting a plurality of light beams, a light deflector (5) for deflecting the plurality of light beams, and a scanning imaging optical system for imaging the light beams deflected by the light deflector on a scanning target surface. The scanning imaging optical system comprises two resin lenses (6, 7) and one glass lens (8). The two resin lenses and the one glass lens are arranged on an optical path from the light deflector to the scanning target surface (9), in this order. The glass lens has a positive power only in a sub-scanning direction. With respect to clearances of light beams most alienated in the sub-scanning direction of the plurality of light beams passing through the two resin lenses and the one glass lens, the clearance at the glass lens is equal to or larger than the clearance at the two resin lenses. <P>COPYRIGHT: (C)2013,JPO&INPIT |
