Abstract: A circuit for exciting an ultrasonic transducer element comprises a diode switch exhibiting a long reverse recovery time duration connected between an input and an output terminal. A transducer exciting signal varying in both positive and negative directions and applied to the input terminal is conducted to the output terminal through the diode switch.

Abstract: In an ultrasonic imaging system including an array of ultrasonic oscillators, ultrasonic beams are electronically scanned by sequentially selecting a plurality of oscillator sets for beam transmission and reception. For one transmission of ultrasonic waves, at least two receiver oscillator sets having at least some oscillators in common are simultaneously selected, and the respective outputs from the oscillators in the at least two receiver oscillator sets are phase-adjusted so that echoes received by the at least two receiver oscillator sets effectively correspond to echoes substantially emanating from at least two respective different points on a depth level distanced from the plane of the oscillator array by a predetermined depth, whereby at least two signals and hence at least two successive scan lines relating to the echoes from those respective different points are produced. As a result, improved line resolution and rapid line acquisition can be obtained.

Abstract: There is disclosed an ultrasonic tomography apparatus of electronic scanning type in which an array of ultrasonic transducer elements are excited with desired time delays allotted for the transducer elements thereby to transmit and receive ultrasonic beams at a deflection angle corresponding to the desired time delays, and the received echo signal of the ultrasonic beams is displayed on a CRT display device in a form of a tomograph of a sample to which the ultrasonic beams are directed. The apparatus comprises a memory in which both of first signals representative of the time delays given to the transducer elements in dependence on given deflection angles and signals designating display position in the X- and Y-directions of the CRT are previously stored and read out for producing delays allotted for the transducer elements and displaying the received echo signal on the CRT.

Abstract: In a method for controlling ultrasonic waves wherein a plurality of elements constituting a phased array ultrasonic transducer are driven with desired delay times, the improvement therein comprising the fact that when values obtained by quantizing the delay times by a predetermined time are different between the adjacent elements, the ultrasonic waves are radiated with a delay of time corresponding to the difference.