| 摘要 |
<p>A phase difference measuring apparatus of the present invention transmits a signal to an object in reference state and receives a first signal. It also transmits a signal to the object in a measurement state and receives a second signal. A reference phase difference theta 1 is obtained from the transmitted signal and the first received signal, and an apparent phase difference theta 2' is obtained from the transmitted signal and the second received signal. The apparent phase difference theta 2' is added to the product of an angle 360 DEG and the number of revolutions n which represents the number of times of passage of the apparent phase difference theta 2' on a certain reference point, and a true phase difference theta 2 is obtained. Here, the number of revolutions is changed to n = n+1 when the apparent phase difference theta 2' passes by the reference point while increasing, and is changed to n = n-1 when the apparent phase difference theta 2' passes by the reference point while decreasing. <IMAGE></p> |
