Patent ID: 9108221
Filing Date: 2015-08-18
Classification: B06B,Y10T

Abstract:
1. A dual-frequency ultrasound transducer, comprising: a substrate; a single piezo-electric element bonded to the substrate, wherein the diameter of the substrate is greater than the diameter of the piezo-electric element; wherein the transducer has a low frequency mechanical bending resonance mode when the piezo-electric element is excited, in use, by a voltage which includes a low frequency oscillating component in the range of 20 kHz to 500 kHz; wherein the transducer has a high frequency thickness resonance mode when the piezo-electric element is excited, in use, by a voltage which includes a high frequency oscillating component in the range of 500 kHz to 5 MHz; and wherein a combined thickness of the substrate and the piezo-electric element is determined on the basis of a desired high resonant frequency in the range of 500 kHz to 5 MHz, and wherein the diameters of the piezo-electric element and the substrate are determined on the basis of the combined thickness and a desired low resonant frequency in the range of 20 kHz to 500 kHz.