An ultrasonic diagnostic apparatus including a compound scanner, a transmitting and receiving control circuit, a digital scanning convertor, a display section, a mode change-over switch, a position signal generator and a heart beat synchronizing signal generator, whereby operation of the change-over...http://www.google.fr/patents/US4463763?utm_source=gb-gplus-shareBrevet US4463763 - Ultrasonic compound scanning diagnostic apparatus
