| 摘要 |
PURPOSE:To provide the plastic-made rotary polygon mirror which is lightweight and suitable for mass-production and has small deformation even in high-speed rotation and also has good precision. CONSTITUTION:The plastic-made rotary polygon mirror has a recessed part 3 in one end surface 3a whose internal surface consists of reflecting surfaces 4a-4c and also has a circular outer peripheral surface 2c; when the rotary polygon mirror is manufactured, a top force has plural reflecting surfaces precisely formed at its projection part and the plastic-made rotary polygon mirror which has small deformation even in high-speed rotation and has high precision can be manufactured at low cost by a shaft part formed as a positioning and motor shaft fitting hole at its center position and a hole part at the center position of a bottom force. |
