| 摘要 |
PURPOSE:To easily know the outputted ultrasonic level every time without storing a related parameter in a large quantity of PROMs in order to know the outputted ultrasonic level by estimating an acoustic pressure level beyond the opening surface of a vibrator from a waveform from an inverse Fourier transformation part. CONSTITUTION:An estimated driving waveform or a measured driving waveform for driving a probe is obtained. Also, a frequency characteristic and a phase characteristic of the probe are obtained. Subsequently, a spectrum obtained by executing Fourier transformation from a time base with respect to the obtained driving waveform is obtained. Next, from the derived spectrum and the frequency characteristic and the phase characteristic, a multiplied spectrum is obtained. Next, the multiplied spectrum is added by an element number portion, and the result of its addition is obtained as total power on a frequency axis. Next, the correction of the obtained power is executed. Thereafter, its power is subjected to the inverse Fourier transformation and from the frequency base, the waveform of the time base is obtained. Next, from a part of the obtained power waveform, a parameter is evaluated. Next, from the result, an ultrasonic output level beyond the opening surface is estimated. |
