| 摘要 |
PURPOSE:To provide a higher speed, longer life and better scanning accuracy and to widen a scanning width with a short optical path length by forming a mirror face to a plane inclusive of the central axis of rotation of a shaft which is rotationally supported by gas bearings. CONSTITUTION:The cylindrical shart 1 supported by the gas bearings 2 is rotated at a high speed by a driving means 3. the mirror face 4 is formed on the plane inclusive of the central axis of rotation of the end face side of the shart 1. High-speed scanning of a light beam is thereby executed without contact with the revolving shaft and the wider scanning width can be taken. The deviation in the scanning position by a difference in the accuracy of a surface tilt in the case of a polygonal mirror is eliminated. |
