PURPOSE: To provide possibility of obtaining a transmitting pulse signal in high precision by emitting a clock signals with n-phase, selecting a clock signal with a certain phase out of these n-phase clock signals, counting these signals, and thereby eliminating setting error of the delay time.
CONSTITUTION: When a start signal for indication of diagnostic image is supplied to a main control circuit 30, an n-phase clock generating circuit 22 is put in operation to emit for ex. a four-phase clock signal. A clock selector circuit 24 selects a clock signal with specified phase set on each of the vibrators 10 in the number of pieces (n). As this clock signal with specified phase, the third phase clock signal is to be selected in case a delay time T of 680nsec is given, and this becomes clock signal with different phase according to the vibrator 10. The clock signal with specified phase is supplied to a counter 36, and the clock is counted, and in case the delay time is 680nsec, the count number 9 is counted down. When the counting becomes zero, a trigger generating circuit 28 is actuated to give a trigger signal with a specified number of pulses to a high voltage pulse generator circuit 12.
KIDO TAKUMI
KIMIDA YUUJI
OKADA NORITOMO
Next Patent: SIGNAL RECEIVER FOR ULTRASONIC DIAGNOSTIC DEVICE