| 摘要 |
PURPOSE:To deduce a vibrating elastic body by detecting with high accuracy a plurality of recessed sections of different depth which are formed in the vibrating elastic body of an ultrasonic motor. CONSTITUTION:In and outside a vibrating elastic body 3 which is mounted on a rotary table 4, fiber sensors, each of which is constituted of a light- receiving section 1 and a light-emitting section 2, are located, and a change in a quantity of light which is detected through recessed sections of the elastic body 3 which rotates together with the rotary table 4 which rotates at a constant speed is amplified by an amplifier 6 and a phase of the vibrating elastic body 3 is calculated by a signal processing circuit 5 and then the vibrating elastic body 3 is indexed. |
