| 摘要 |
PURPOSE:To simplify the structure of an optical system by performing scanning along a projection body while imaging light on the projection body through the rotation of a mirror body which has a reflecting mirror surface provided spirally around a rotary shaft. CONSTITUTION:A cylinder 1 has a spiral mirror body 2 on its external circumferential surface. The mirror body 2 is equipped with a spriral reflecting mirror surface 5. A driving body 4 rotates the cylinder as shown by an arrow and incident light 6a parallel to the axial line of a rotary shaft 3 is made incident from a light irradiation device 6 to the reflecting mirror surface 5. Consequently, the reflecting mirror surface 5 shifts in position according to the rotation position of the cylinder 1. As a result, the position of reflected light 6b imaged on a projection body 8 moves on the surface of the projection body 8 according to the rotation of the cylinder 1. Namely, reflected light 6a is scanned. Thus, the structure of an optical system is simplified. |
