| 摘要 |
PROBLEM TO BE SOLVED: To reduce the heat generated in a sealed room by a deflector and to prevent the heat from being transmitted to another optical element. SOLUTION: An optical scanner 1 is provided with the deflector 4, a light source part and first, second image forming optical systems. The deflector 4 provided with a polygon mirror 2 and a motor 3 rotating the polygon mirror 2 is set up in a sealed space constituted of a transmission window 8, a bottom plate 9, an outer wall 10 and a cover 11. Then, by sucking air in the sealed space out from a sucking port 13 to the outside, the sealed space is made a state close to vacuum. By such a manner, the effect of the heat generation in the deflector 4 is reduced. |
