JPS6415033A - Ultrasonic doppler diagnostic apparatus - Google Patents

Abstract

PURPOSE:To well perform measurement even an reflecting body moving at a long distance and high speed, by a method wherein an ultrasonic pulse wave is divided timewise to be transmitted to and received by an object to be examined while successively changed in a direction and the receiving signals are respectively converted to receiving signals having desired frequencies to calculate radial speeds which are, in turn, compared with each other to operate the tangential speed of a sector scanning circular arc. CONSTITUTION:The output of a quartz oscillator 10 is supplied to a frequency dividing synchronous circuit 12 to output pulse signals 101, 102 having two kinds of burst frequencies and said signals are changed over in synchronous relation to the integral multiple of a repeating cycle by change-over devices 14, 16 to be supplied to a probe 22. The refelected echo from an object 23 to be examined is sent to a high frequency amplifier 26 from a duplexer circuit 20 and one output thereof is supplied to a display part while the other output is subjected to speed operational processing and converted to a complex signal to be supplied to a self- correlation operator 60 and operation is performed at every ultrasonic pulse wave emitted in a time sharing manner. By this method, a speed component is calculated but, on the basis of signals separated by a fine angle in two directions, a radial speed and a tangential speed are calculated by the first and second comparators 70, 80 to be supplied to a vector speed operator 90. The output thereof is supplied to a CRT display device 32 from a D/A converter 37.