Patent ID: 7902722
Filing Date: 2011-03-08
Classification: A61B,B06B,Y10T

Abstract:
1. A transducer comprising: a central rod having a conductive layer deposited thereon; a first spiral groove of a determined pitch extending laterally in said conductive layer along said rod, said pitch being determined based on an operating frequency of said transducer and a launch angle of a transmitted beam; a second spiral groove extending laterally in said conductive layer along said rod, said second spiral groove having a pitch substantially similar to that of said first spiral groove and being offset from said first spiral groove by a known distance, wherein a first set of electrically isolated first and second conductive bands are formed between said first and second spiral grooves; a piezoelectric material of a known thickness deposited on at least said first and second conductive bands for generating an acoustic wave; said thickness being determined based on a desired frequency of operation, said piezoelectric material on said conductive bands forming a first set of first and second electrodes; and a conductive layer deposited on top of said piezoelectric material forming a conductive electrode with respect to each of said first and second electrodes, wherein an impedance of said transducer is based on at least one of: an inductance component dependent upon a permeability of said central rod, a capacitance of said transducer and an application of a voltage to each of said conductive bands.