| 摘要 |
PURPOSE:To simplify the structure by dividing an optical beam to N bits of split optical beams and reducing considerably the number of light sources even though there are many partial scanning regions. CONSTITUTION:An ultrasonic optical polarizer 23 recives one optical beam from a light source 22 and outputs N bits (two, in this example) of split optical beams different in angle, and a plane mirror 24 receives these split optical beams and reflects them to plane mirrors 25a and 25b, and they are made incident to a polyhedral mirror 21. The rotary polyhedral mirror 21 has n each (ten, in this example) of specular faces and is rotated in a high speed in the direction of an arrow by a motor (which is not shown in a figure). Reflected light from individual specular faces scan a scanning through focusing optical systems 26a and 26b and plane mirrors 27a and 27b. The whole scanning region is divided into partial scanning regions A1 and A2 in the scanning direction, and the region A1 is scanned by one beam, and the region A2 is scanned by the other. Thus, carrier waves having frequencies f1 and f2 (fnot equal to f2) are supplied to the ultrasonic optical deflector 23 having the angle control function and the spectral function to obtain two split optical beams from one incident beam. |
