Abstract: Within the tip portion of a cylindrical shaped sheath a capacitive ultrasonic transducer which is an array type two-dimensionally arrayed on the outer surface of the cylindrical face is disposed. Capacitive ultrasonic transducer units employ m capacitive ultrasonic transducer elements arrayed in the longitudinal direction of the cylindrical face as a division unit, thereby providing an arrangement wherein the respective capacitive ultrasonic transducer units are readily disposed in the circumferential direction, whereby radial scanning or the like can be performed within a body cavity.

Abstract: An ultrasonic probe apparatus which applies a RF pulse signal with a DC bias signal superimposed thereon to c-MUTs and transmits/receives an ultrasound wave is configured such that a transmission control system includes bias regulators which regulate the voltage value of the DC bias signal, a reception control system has a plurality of different frequency band pass filtering characteristics including at least those for a low pass and high pass and a frequency band pass filtering processing section which can select at least one frequency band pass filtering characteristic from those frequency band pass filtering characteristics. The apparatus controls voltage settings of the bias regulators in conjunction with the selection of frequency band pass filtering characteristics of the frequency band pass filtering processing section.