| 摘要 |
PURPOSE:To attain tracking at a high response speed with simple constitution without using any mechanically mobile part, by using an acoustic/optical deflector for tracking. CONSTITUTION:An acoustic/optical deflector 24 is used in place of a normal tracking mirror. This deflector 24 is produced by attaching a transducer 34 such as a comb-shaped electrode, etc. to the side face of an acoustic/optical medium 37 containing an LiNbO3 piezoelectric crystal, etc. When a high frequency signal 35 is applied to the transducer 34, the incident light 30 is diffracted by ultrasonic traveling wave 36 and delivered in the form of a diffracted beam 32. This beam 32 is varied by the length of the wave 36 with an extremely high response speed, i.e., several musec. Thus it is possible to deflect quickly the light 30 in an optional direction within a prescribed range by changing the frequency of the signal that is supplied to the transducer 34. |
