An ultrasonic imaging arrangement performs tentative scanning of ultrasound to
the inside of a living body with delay time corresponding to average sonic velocity,
calculates delay time error in a delay time error detecting circuit by using received
signals from each channel to which delay control has been performed in a digital
delay circuit, compares in a delay time comparing unit the calculated data with
a plurality of delay time error data corresponding to various sonic velocities
using sound velocity as the parameter stored before hand in a sound velocity-derived
delay time error storing unit, selects among those sonic velocities the one matching
the delay time error data with a sonic velocity selecting unit, and calculates
the sonic velocity within the living body. The calculated sonic velocity is fed
back to CPU, and the delay data on the delay applied in the ultrasonic scanning
is provided to a delay circuit.