PURPOSE: To give a received and focused diagnostic image in a real time, by controlling the timing for shifting the phase of a reference signal so as not to allow the same to coincide with the receiving timing of an ultrasonic reflected pulse.
CONSTITUTION: A control circuit 2 successively writes the timing (time interval) toggled by a frequency dividing circuit in a memory 23 through the R/W control circuit 21 of a reference signal generating circuit 1 and the digital signal obtained by the A/D conversion of the output of a joystick 9 is inputted to the control circuit 2. A CPU 20 confirms the inputted digital signal as a specific position and previously writes the value of the memory so that the timing receiving the ultrasonic reflected pulse from said specific position does not shift the phase of a reference signal Q0. By this constitution, when the internal position of an examine desired to the subjected to the analysis relating to the frequency of a receiving signal is indicated on a diagnostic image by the joystick, the timing of the phase shift of the reference signal exerting no effect on the analysis relating to frequency can be automatically set in a real time.
SUGIYAMA YUICHI
SHIMURA NOBUSHIRO
HAYASHI OSAMU
