Method and apparatus for measuring ultrasonic velocity in a medium by crossed beams

摘要

A measuring apparatus (100) for an ultrasonic velocity (Co) in a region of interest (ROI) within a medium (54) includes an array transducer (10), and a velocity measuring circuit (30). The transducer (10) is constructed of a plurality of transducer elements which are subdivided into at least first and second transmitting sections (11; 12) and first and second receiving sections (13; 14) separated by a distance (do). First and second ultrasonic beams are emitted from the first and second transmitting sections (11; 12) to the ROI under the condition that the transmitting beam axis is intersected by the second ultrasonic beam axis. Then, the first and second receiver sections (13; 14) receive in total four echoes reflected from four corners (J; K; L; M) of the ROI. The velocity measuring circuit (30) calculates the propagation time of the ultrasonic beams and finally the ultrasonic velocity (Co) based upon the propagation time.