| 摘要 |
PROBLEM TO BE SOLVED: To prevent a rotary polygon mirror from generating a positional deviation. SOLUTION: A bearing surface metal fitting 32 is attached to the upper end of a cylindrical rotary shaft 31 made of ceramics and a metallic rotary polygon mirror 33 is engaged with the fitting 32. A hole part 34 is formed on the center part of the mirror 33 and an approximately cylindrical part 35 of the fitting 32 is inserted into the hole part 34. Plural slits 36 are formed on the cylindrical part 35 in the axial direction, the cylindrical part 35 is formed as a tapered taper part 37 and a collar part 38 having a step part recessed to the inside is formed on the base part of the taper part 37. Further, the fitting 32 is also provided with a bearing surface part 39 for receiving the mirror 33. |
