To provide an optical scanner which is improved in optical performance without changing the machining method and cost of a plastic scanning lens; and to provide an image forming apparatus with the optical scanner mounted thereon, and is high in image quality.
The optical scanner 5 includes: a plurality of light sources for emitting light beams; an optical deflector 2 for deflecting light beams from the plurality of light sources; and an imaging optical system which images the plurality of light beams 9-1, 9-2 deflected by the optical deflector 2 on a surface 4 to be scanned that has a length in the main scanning direction and a sub-scanning direction orthogonally crossing each other. The imaging optical system has a plastic scanning lens 1 arranged facing the optical deflector 2. The plurality of light beams 9-1, 9-2 are made incident, with different incident angles, on different sub-scanning direction positions on the plastic scanning lens 1. The external form center position of the plastic scanning lens 1 in the sub-scanning direction and in the center line direction 6 is located on the center line 6 in the sub-scanning direction of the plurality of light beams 9-1, 9-2.
HIRANO AKIO
OHASHI TAKAMICHI
TAKAHASHI TAKESHI
AOKI MIKI
| JP2009122329A | 2009-06-04 |
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