Echo ultrasound system with an improved image sequence rate

An echo ultrasound imaging system comprising at least one array of elementary transducers, and further comprising an emission stage and a stage for the reception and for the processing of echoes reflected back towards the said array, said reception and processing stage having means for the simultaneous focusing of M ultrasonic beams originating from M different directions; the emission stage has means for the focusing of M ultrasonic beams emitted sequentially in the said M different directions, and during a total duration defined by the sum of the M maximum delays of the M delay laws forming the said M focused beams emitted.