To realize an excellent plane tilt precision with a low cost by resolving the degradation of plane tilt and planeness as a problem for the use of an inexpensive glass mirror in the driving device used in an LBP.
This driving device is provided with a rotor unit 13 and a stator unit 14 which is provided with a bearing 15 axially supporting a revolving shaft 1, and the rotor unit 13 is provided with a polygon mirror 2 like a thin plate which has two faces facing each other or one face as a reflection face, and a columnar rotor boss 5 to which the polygon mirror 2 is fixed, and a revolving shaft 1 fixed to the center of the rotor boss 5. The rotor boss 5 has a plane part 5a in one end face, and only one end face of the polygon mirror 2 is directly fixed to the plane part 5a by adhesion, and the bearing 15 consists of a fluid bearing to have a constitution capable of plane tilt adjustment.
OHATA KOICHIRO
MATSUMOTO TOSHIAKI
