| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical deflector that can reduce the number of times of applying balance weights as much as possible and suppress fatigue failure of a rotor frame, a scanning optical device, and an image forming apparatus.SOLUTION: There is provided an optical deflector 55 that includes a rotor having a rotor frame 6 formed of a steel plate and a rotary polygon mirror 54 rotating with the rotor frame 6, where the mass of the rotor frame 6 is the largest of that of a plurality of members constituting the rotor, and balance weights 14a and 14b are applied to a part of the rotor to correct a dynamic balance of the rotor. The rotor frame 6 is lighter than 3 g, and the thickness of the steel plate is set in a range in which: when the rotor is rotated, the stress amplitude at a portion of the rotor frame 6 on which the largest stress acts becomes smaller than fatigue limit.SELECTED DRAWING: Figure 1 |
