| 摘要 |
PURPOSE:To improve depth resolution to accurately detect phase difference and an amplitude value by providing an ultrasonic probe, a multiplier, a peak detector, a phase changing means, a means for obtaining a maximum detection peak value, a phase value output means, etc. CONSTITUTION:A computer 12 has a delay controlling function of a variable delay line 6. The delay means that a phase of a reference signal is changed, wherein phase section delay control of 0 to 360 deg. is performed. The phase change is performed in DELTAtheta units of a regulated pitch phase. That is, the phase is sequentially updated (set) as 0 deg. DELTAtheta 2DELTA-theta 3DELTAtheta ...360 deg., ultrasonic measurement by means of impulse excitation is done for each phase and a peak value is detected. The peak value is obtained for each updated (set) phase in 0 to 360 deg. sections, and the computer 12 detects the maximum peak value from the plurality of peak values. A phase of the variable delay line 6 when the maximum peak value is obtained is also calculated. The maximum peak value (maximum value) is an inherent amplitude Am of a reception echo and the phase at this time is an inherent phase value PHI of the reception echo. |
