| 摘要 |
<p>In an ultrasonic diagnostic apparatus using an array type transducer probe, wherein improved tomographic image resolution is desired by electronically focusing ultrasonic wave toward an object to be examined in both directions, i.e., the array direction and the lens direction. During first scanning of the ultrasonic transducer array in the array direction, the signals received from the probe are synthesized in phase with respect to each other via delay lines having predetermined delay times to obtain first scanned signals in real time, so that focusing the reflected ultrasonic wave can be electronically accomplished in the array direction. After this first scanning, the probe is mechanically moved to a given position in the lens direction normal to the array direction. Then a second scanning operation is accomplished to obtain similar first scanned signals. All of the first scanned signals are processed by a delay time control circuit, digitized, and then stored. Finally, all of the stored first scanned signals are read out and synthesized in phase with respect to each other by an adder circuit to obtain second scanned signals, so that focusing the reflected ultrasonic wave can be accomplished in the lens direction. The resultant second scanned signals are converted into analogue signals to be displayed as a tomographic image of the desired diagnostic part in the object.</p> |
