| 摘要 |
PROBLEM TO BE SOLVED: To provide a scan optical device for preventing image deterioration generated due to light quantity insufficiency caused by stain of optical components such as lenses and mirrors. SOLUTION: A laser scanner unit (scan optical device) 30 stores: a first optical system I including a polygon mirror 35 polarizing and scanning a light beam and a first imaging lens 36 arranged on an optical path of its scan light in a housing 31 covering an upper face opening part by a cover; and a second optical system II including a second imaging lens 37 and a turn-up mirror 38 arranged on the optical path. The laser scanner unit substantially closes a first space S1 storing the first optical system I of the housing 31, opens a second space S2 storing the second optical system II in the housing 31 to be an air duct, and forms opening parts 45, 46 opened to the second space S2 in at least two opposite parts of the housing 31. COPYRIGHT: (C)2010,JPO&INPIT |
