| 摘要 |
PURPOSE:To obtain the title apparatus capable of accurately and automatically judging the state of a specimen by analyzing the frequency of the reflected wave of the ultrasonic signal projected on the specimen and forming two reference waves different in phase from the band of the center frequency component thereof to mix the same with the reflected wave and detecting the output signal thereof. CONSTITUTION:When a signal is applied to a probe 4 from a pulse generator 50, an ultrasonic wave is generated to be projected on an object 3 to be inspected and the reflected wave is received by the probe 4 to be inputted to a peak detector 70. A frequency analyser 12 calculates the center frequency component of the reflected wave and the signal thereof is sent to a synthesizer 15 which in turn generates a reference wave RFW of the same frequency. The reference wave is converted to reference waves having phase difference of 0 deg. and 90 deg. by a phase shifter 16 and these reference waves are respectively mixed with reflected waves branched in two directions by mixers 17, 18. Since this mixing result is shifted by 180 deg. in phase between normal and abnormal cases, a CPU displays judgement and the adhesion release of the object to be inspected can be accurately detected. |
