1. In a device for examination of an object by ultransonic pulses, said device including a transmitter of recurrent electric pulses, a transmitting-receiving ultrasonic transducer energized by this transmitter and subjected to a linear displacement, a receiver of reflected pulses coupled to said transducer, a recording tube coupled to said receiver and having a memory target, a writing electron beam with an horizontal and a vertical scan and a reading electron beam, means for synchronizing said horizontal scan with the displacement of the transducer and for synchronizing the said vertical scan with the repetition rate of the transmitted pulses, a television scan generator supplying scan signals which control the scanning of the memory target by the reading electron beam, and a display tube controlled by said scan generator and modulated by the reading signal supplied by the recording tube, the improvement which consists in that the said device further comprises a function generator supplying further scan signals and means coupled to said function generator for modulating the scanning of the memory target by the reading electron beam by means of the said further scan signals, thereby to move the reading electron beam along successive curve portions arranged on a plurality of horizontal scanning lines.