| 摘要 |
PURPOSE:To enlarge the visual field of a scanning direction by disposing plural detecting elements on the same circumference whose center is the rotating axis of a scanning mirror and separating the position of the rotating axis from the mirror surface of the scanning mirror. CONSTITUTION:The detecting elements 4b and 4c are dislocated from a center line 6 on the same circumference whose center is the rotating axis 5 and the mirror surface of the scanning mirror 3 and the rotating axis mirror 5 are separated by a distance G. The detecting elements 4b, 4c are dislocated from the center line 6 and the rotating axis 5 of the scanning line is separated from the scanning mirror surface, thereby, an optical system efficient characteristic is asymmetric with respect to the center line and the visual field is also asymmetric. Synthesizing the output signals of the plural detecting elements, the visual field of a scanning direction is enlarged. |
