Abstract: An ultrasonic probe includes a housing, and a plurality of piezoelectric elements radially arranged in a plane substantially perpendicular to a direction in which the ultrasonic probe is inserted into a hollow portion to be scanned. The ultrasonic probe also includes an electrical part for carrying electricity to the piezoelectric elements to thereby cause the piezoelectric elements to emit ultrasonic waves and for carrying, to an external device, electric signals generated from the ultrasonic waves reflected by the hollow portion and received by the piezoelectric elements.

Abstract: An ultrasonic probe includes a housing, a piezoelectric element provided in the housing, the piezoelectric element emitting an ultrasonic beam, and a refracting member rotatably provided in the housing. The refracting member has a first surface opposite to the piezoelectric element and a second surface at which the ultrasonic beam emitted from the piezoelectric element and passing through the first surface is deflected in a state where a deflection angle between an axis perpendicular to a surface of the piezoelectric element and a deflected ultrasonic beam changes as the refracting member rotates.

Abstract: A plurality of rectangular piezo-electric ultrasonic sector transducers are aligned to form an array, and each transducer has first and second electrodes on its radiating surface. The first electrode is located on a center line of the sector transducer's length, and has a first length in the longitudinal direction and a first width along the center line. Two of the second electrodes are arranged outside the first electrode, symmetrical to the center line. The two second electrodes have a second length in the longitudinal direction longer than the first length, and have a second width which is almost the same as the first width, along a line near the center line. Thus, diamond-shaped electrodes excellent for providing a beam narrow in the longitudinal direction can be employed as the first electrode, and the combination of the first and second electrodes can be connected to each other.