An ultrasonic imaging method and apparatus wherein the ultrasonic energy transmitted to a subject under examination is generated by a plurality of electroacoustic transducers, which are actuated for transmission with predetermined delays according to a predetermined focusing rule; the ultrasonic energy reflected by the subject under examination is received by an array of electroacoustic transducers which are actuated to read received signals with predetermined delays according to a received signal focusing rule. The focused received signals are turned into image data for ultrasonic image display. The transmitting transducers are actuated with such delays as to generate a homogeneous acoustic field over all or part of the region of the subject under examination.