| 摘要 |
PURPOSE:To remove phase measurement errors caused by the deflection of a scanner shaft by correcting a phase according to detected phase data. CONSTITUTION:A burst wave signal from a signal transmitter 5 is projected to a body to be inspected 3 and standard body to be inspected 13 and the reflected waves are received by supersonic wave probes 4a, 4b to be outputted from the probes 4a, 4b as the reflected wave signal and standard reflected wave signal. A reference signal from a transmitter 6 is distributed by a distributer 7 to be inputted to mixers 9a, 9a as a measuring reference signal and to mixers 9b, 9b as a standard reference signal. The reflected wave signal and measuring reference signal are mixed by the mixer 9a and the standard reflected wave signal and standard reference signal are mixed by the mixer 9b, respectively. Only DC component is extracted by a low pass filter 10 to input measuring data and correction data to a computer 11. Respective amplitudes and phases are obtained by the computer 11 to be stored in a memory. The phase difference of measured correction data is subtracted from the phase value of stored measured data to remove the variation of phase caused by the deflection of a scanner shaft. |
