Method and apparatus for phased array coupling ultrasonic energy into an acoustic waveguide wire

An apparatus for invasively transmitting ultrasonic energy into a body comprising:

• a flexible waveguide wire having a proximal end and a distal end, said waveguide wire having an outer surface;
• a phased array of ultrasonic transducers arranged along said outer surface near said proximal end;
• and
• a bulbous member at said distal end of said waveguide wire to vibrate in response to acoustic energy generated by said phased array.

A method of transmitting ultrasonic energy into a body comprising the steps of:

• providing a waveguide wire having an input end having an axis and an outer surface;
• attaching an array of ultrasonic transducers in energy-transfer relationship with said outer surface such that said ultrasonic transducers are at dissimilar distances relative to said input end;
• and
• individually exciting said ultrasonic transducers, including applying phase-shifted signals for which a signal applied to an ultrasonic transducer of said array has a selected phase-differential relationship with respect to signals applied to adjacent ultrasonic transducers,
• wherein ultrasonic signals generated by said ultrasonic transducers enter said waveguide wire via said outer surface.