| 摘要 |
PURPOSE:To provide the optical deflector which has high rotation precision and low vibration characteristics by preventing the rigidity of a dynamic pressure air bearing from decreasing. CONSTITUTION:A rotary polygon mirror 11 and a magnet yoke 5 which supports rotary magnets 6-1 and 6-2 are fixed and a rotary sleeve 3 which constitutes a fixed shaft 1 and the dynamic pressure air bearing are composed of a cylinder part 3-1 and a mirror flange 3-2 which is fixed to the outer periphery of the cylinder part 3-1 across a magnetic which has a smaller Young's modulus than the cylinder part 3-1. The centrifugal force based on the rotation of the rotary polygon mirror 1 operates only on an external cylinder part and the gap between the fixed shaft 1 and internal cylinder part does not expand, so the rigidity of the dynamic pressure air bearing does not decrease and a decrease in rotation precision and the generation of resulting vibration can be evaded. |
