| 摘要 |
PURPOSE:To display variation in the center frequency of an echo signal by expanding spectral variation of the echo signal as a differential of zero-cross density by attenuation due to the propagation of an ultrasonic wave in organic tissue and attenuation due to reflection and scattering. CONSTITUTION:An ultrasonic wave transmitted by a probe 3 is reflected partially in a body (living body) 1 to be measured and then received as an ultrasonic echo signal by the probe 3. The received echo signal is supplied to an STC (time sensitivity controller) 6 for STC correction through a receiving circuit 4 and a logarithmic amplifier circuit 5 and outputted as an echo signal 100. This signal is stored in memory 8 through a detecting circuit 7. The signal is read out of the memory 8 under the control of a control circuit 11 and displayed on a display part 10 as a visual sectional image of the body 1 through a video amplifier 9. Consequently, variation in the center frequency of the echo signal due to organic tissue is grasped intuitively on real-time basis from the display image. |
