PROBLEM TO BE SOLVED: To provide a method and apparatus for highly accurately measuring an ultrasonic wave propagation time by measuring the ultrasonic wave propagation time while taking into account not only non-linear acoustic characteristics of an ultrasonic wave propagation medium but also transfer characteristics or ultrasonic wave propagation characteristics of an ultrasonic transducer.SOLUTION: A transmission pulse signal Vtrans(t) is generated by a transmission section 110, converted into an ultrasonic pulse signal Sx(t) by a transmission ultrasonic transducer 130, and input to an ultrasonic wave propagation medium 10 of a measuring target. The ultrasonic pulse signal Sx(t) propagated via the ultrasonic wave propagation medium 10 is received and amplified by a reception ultrasonic transducer 140 to obtain a reception pulse signal Vrec(t-τ). In a signal processing section 170, mutual correlation processing is performed between a reference signal considering non-linearity that the ultrasonic wave propagation medium 10 has and a referenced signal, thereby detecting a time interval between transmission and reception of the ultrasonic pulse signal Sx(t) propagated via the ultrasonic wave propagation medium 10 as an ultrasonic wave propagation time.COPYRIGHT: (C)2012,JPO&INPIT【課題】超音波伝搬媒体の非線形音響特性、さらには超音波トランスデューサの伝達特性や超音波伝搬特性をも考慮した超音波伝搬時間計測を行うことによって高精度に計測方法および装置を提供する。【解決手段】送信部110により送信パルス信号Vtrans(t)を発生し、送信用超音波トランスデューサ130により超音波パルス信号Sx(t)に変換して測定対象の超音波伝搬媒体10に入力し、前記超音波伝搬媒体10を介して伝搬される前記超音波パルス信号Sx(t)を受信用超音波トランスデューサ140により受信し増幅して受信パルス信号Vrec(t-τ)を得て、信号処理部170において、前記超音波伝搬媒体10が有する非線形性を考慮した参照信号と被参照信号との間で相互相関処理をすることによって、前記超音波伝搬媒体10を介して伝搬される超音波パルス信号Sx(t)の送受信間の時間間隔を超音波伝搬時間として検出する。【選択図】図1
