| 摘要 |
PURPOSE:To increase the number of scanning lines without increasing the number of laser diodes by allowing the reflection surface of a scanning mirror body performing scanning with a laser beam to have plural angles to the rotary shaft of the scanning mirror body. CONSTITUTION:In a polygon mirror type scanning mirror body 21, the reflection surfaces 22a to 22c having three kinds of angles to the direction of the rotary shaft 23 are succesively arranged side by side, reflect the laser light beam L radiated from the laser diode 11 being a laser beam generating system so as to irradiate a transmission system, and make it incident on a rotary screen 41. The laser beam reflected by the reflection surface 22a of the mirror body 21 scans from the -Y direction to the +Y direction of the screen 41 associated with the rotation of the mirror body 21, so that the scanning line 50a is generated. The laser beam reflected by the reflection surface 22b and 22c generates the scanning line 50b on a position distant from the scanning line 50a in a +X direction, and further generates the scanning line 50c on a position distant from the scanning lin 50b in the +X direction. Thus, three scanning lines 50a, 50b and 50c are generated by one laser diode 11. |
