| 摘要 |
PURPOSE:To exactly detect a time shift by deriving a singular point in a first partial area like a time series of a receiving signal, deriving a second partial area of the receiving signal, based thereon, detecting a time shift, based on the receiving signal in this area and controlling the delay quantity. CONSTITUTION:A reflected wave of an ultrasonic wave from a body to be examined is received by an electro-acoustic transducing element 1 and inputted to a receiving part 3. As for each delayed signal outputted from the receiving part 3, the part of a first partial area is stored in a receiving waveform memory 61, and a center element receiving signal of the acoustic transducing element 1, thereof is inputted to a maximum value detecting means 91 of a time shift detecting position setting part 9. Subsequently, a point in which the maximum value P of the signal exists is inputted to a time shift detecting position changing means 92, and a second partial area is set. An exact time shift is derived by a time shift detecting part 7 from them, and based thereon, adjustment of each delay quantity to the receiving signal of the receiving part 3 is executed. In such a way, even in the case a strong reflector exists in the vicinity of a scanning line, a time shift is detected correctly. |
