Patent ID: 6489982
Filing Date: 2002-12-03
Classification: G02B,H04N

Abstract:
A multi-beam scanning optical system comprising:light source means having a plurality of light sources spaced apart from each other at least in a main scanning direction; a first optical system for converting a plurality of divergent light beams emitted from said light source means; deflection means having a deflecting surface for reflecting/deflecting the plurality of light beams in the main scanning direction; a stop which is interposed between said first optical system and said deflection means to limit a width of incident light beams; and a second optical system for forming the plurality of light beams reflected/deflected by said deflection means into images on a scanned surface, wherein letting S1 be an emission point interval between the plurality of light sources in the main scanning direction sources in the main scanning direction, f1 be a focal length of said first optical system, L1 be a distance from said stop to the deflecting surface of said deflection means, f3 be the focal length of said second optical system in the main scanning direction, and N1 be the number of pixels per inch on the scanned surface in the main scanning direction, a condition given by S1Ã—L1f1Ã—f3&leq;25.4N1Ã—14is satisfied.