| 摘要 |
PROBLEM TO BE SOLVED: To realize miniaturization and cost reduction of an optical scanner, while preventing color slippage. SOLUTION: The optical scanner is equipped with a first and second fθlenses 23 and 24 disposed on the optical path of a laser beams from a single deflector 22, a plurality of reflective mirrors 26 disposed on the optical path of lease beams from the first and second fθlenses 23 and 24, and for dividing a plurality of laser beams for every color, photoreceptor drums 2a, 2b, 2c and 2d disposed at an equal interval in the subscanning direction, and one of which is disposed between the deflector 22 and the first fθlens 23, and third fθlenses 25a, 25b, 25c and 25d which are disposed respectively on the optical path of each laser beam from a reflective mirror 26, and which guide the laser beams to the photoreceptor drums 2a, 2b, 2c and 2d after compensating the curvature of image plane of the laser beams. When the distance between the photoreceptor drums is called P, the number of the photoreceptor drums is called n and the focal distance is called F, the relation n×P>F>(n-1)×P is made to hold. |
