Rotary deflector, optical scanning unit and image forming apparatus

摘要

The inventive device reduces noises and stabilizes the image quality of an image forming apparatus by reducing vibration thereof by reducing vibration of a driving source itself within a preset frequency range without changing the resonating condition of a housing. A mass member is added to a stationary shaft of a driving motor for rotating a polygon mirror. It then becomes possible to reduce the vibration and noise of an image forming apparatus by avoiding resonation by moving a resonance point by adding the mass member to the stationary shaft. Thus, a high image quality image forming apparatus can be realized.