| 摘要 |
PURPOSE:To solve a problem that reading a crest value is impossible due to a saturation of a circuit, by using a plurality of amplifying circuit systems having a different amplification degree or amplification characteristic and by reading the outputs thereof. CONSTITUTION:A pulser 1 generates a high-voltage pulse periodically to excite an ultrasonic probe 2. An ultrasonic pulse transmitted from the probe 2 is applied to a substance 3 to be detected and a reflected wave from an acoustically discontinuous part is received by the probe 2. The signal of this reception is subjected to impedance transformation in an impedance transforming circuit 4, separated into two systems and supplied to attenuators 5 and 6. Amplifying circuits 7 and 8 amplify signals of the attenuators 5 and 6. A computer 15 performs instruction of a synchronous signal, collection and recording of data, preparation of a range-amplitude compensating function, etc. The circuits 7 and 8 is made to have different amplification in the respective systems. |
