Patent ID: 7061159
Filing Date: 2006-06-13
Classification: H01L,H02N

Abstract:
1. An ultrasonic transducer comprising: a first set of piezoelectric elements disposed as insulators, at least a first and a second piezoelectric element of the first set of piezoelectric elements respectively forming a top and a bottom of the ultrasonic transducer; internal electrodes; a plurality of second piezoelectric elements, the internal electrodes and the second piezoelectric elements being alternately layered; outer electrodes, each being connected to the corresponding internal electrodes; a first layered part including at least the internal electrodes, each being divided in half in a second direction orthogonal to a layering direction, which is a first direction; a second layered part including at least the internal electrodes, each being divided in half in a third direction orthogonal to the first direction and the second direction, the first layered part and the second layered part being separated by at least a third piezoelectric element of the first set of piezoelectric elements; a first outer-electrode group provided so as to be connected to predetermined internal electrodes in the first layered part; and a second outer-electrode group provided so as to be connected to predetermined internal electrodes in the second layered part, wherein applying alternating voltage to the first outer-electrode group excites longitudinal resonance in the first direction and flexural resonance in the third direction and/or applying alternating voltage to the second outer-electrode group excites the longitudinal resonance in the first direction and flexural resonance in the second direction to generate ultrasonic elliptical vibration in the ultrasonic transducer.