Measurements of sound intensity of ultrasonic waves by the real-time holographic interferometry with BSO single crystal

以硅酸铋单晶为记录材料，采用实时全息干涉技术，在50 ns脉冲激光辐射下，实现了超声声场的瞬时记录。利用梯形近似、Abel逆变换或CT技术分析光程变化，得到超声波的声压瞬时值分布。通过相移法或希尔伯特变换得到了超声波的声压幅值和相位分布，并应用声强法计算了超声波传播方向和垂直方向两个矢量分量的强度分布。虽然超声声场的测量目前还比较困难，但利用该技术可以测量超声波的声压瞬时值、声压幅值分布和声强分布。

Ultrasonic sound fields are instantaneously recorded by using real time holographic interferometry with the recording material of bismuth silicon oxide single crystal in 50ns pulsed laser radiation. Sound pressure instantaneous value distributions of the ultrasonic wave are obtained by analyzed optical path length change with trapezoidal approximation, Abel inversion or CT technique. Sound pressure amplitude and phase distribution of the ultrasonic wave are obtained by phase shift method or Hilbert transform, and it is possible to calculate the intensity distributions of two vector components(direction of propagation and the orthogonal direction) of ultrasonic waves by the application of sound intensity method. Though the measurement of ultrasonic sound field is difficult until now, the measurements(sound pressure instantaneous value, sound pressure amplitude distribution and intensity distribution of ultrasonic wave) become possible by this technique.