| 摘要 |
PURPOSE:To measure the speed component, etc., of a three-dimensional body accurately by irradiating the body with three or more kinds of ultrasonic-wave beams differring in quality in different directions so that they will pass through one part of the body at the same time, and then by performing arithmetic by discriminating respective reflected beams. CONSTITUTION:For example, ultrasonic-wave vibrators 11-13 are three different vibrators and opposed to one blood-flowing part P in the viscera. Ultrasonic-wave pulses emitted from vibrators 11-13 have respective delay times controlled to pass through point P at the same time. Respective ultrasonic-wave beams reflected at measurement point P are converted by ultrasonic-wave vibrators 11-13 into electric signals, which are transmitted to discriminating filter 30 via amplifier 20 to be separated by three filters into three kinds of electric signals corresponding to three kinds of ultrasonic waves. Respective separated signals are passed through gate circuit 40 to extract only reflected signals, which are passed through Doppler shift detecting circuit 60 to detect their frequency shift quantities, and then they are sent to speed arithmetic circuit 70 to calculate respective motion speed components. Thus, the accurate measurement can be performed. |
