Apparatus for and method of producing an ultrasonic signal

Abstract

An ultrasonic actuator comprises a miniature ultrasonic transducer powered by electromagnetic radiation. The ultrasonic transducer comprises a housing defining a chamber. A liquid mass oscillates within the chamber at a frequency within the ultrasonic range. To cause this oscillation, a source of electromagnetic radiation energizes the liquid mass by exposing a portion of the liquid mass to electromagnetic radiation. The source of electromagnetic radiation thus drives the liquid mass at a frequency within the ultrasonic range.

1 - 45 . (canceled) 
     
     
         46 . An ultrasonic actuator comprising:
 a housing defining a chamber;   a liquid mass positioned to oscillate within the chamber at a frequency within the ultrasonic range; and   a source of electromagnetic radiation energizing the liquid mass by exposing a portion of the liquid mass to electromagnetic radiation, the source of electromagnetic radiation driving the liquid mass at said frequency.   
     
     
         47 . An ultrasonic actuator as in  claim 46 , wherein the liquid mass is disposed between a pair of gas springs. 
     
     
         48 . An ultrasonic actuator as in  claim 46  additionally comprising:
 an elongated body defined between a proximal end and a distal end; and   a waveguide for conducting electromagnetic energy, the waveguide extending from the proximal end of the elongated body to the distal end and cooperating with a source of electromagnetic radiation to provide electromagnetic radiation to drive the liquid mass.   
     
     
         49 . The ultrasonic actuator as in  claim 46 , whereas the housing is configured to generator ultrasonic wave propagations. 
     
     
         50 . The ultrasonic actuator as in  claim 49 , wherein the housing cooperates with a ultrasonic receiver, which is part of an imaging system. 
     
     
         51 . The ultrasonic actuator of  claim 46  in combination with a medical apparatus having an elongated body. 
     
     
         52 . A method of producing a ultrasonic signal comprising the steps of:
 (a) providing a liquid mass within a chamber of a housing;   (b) exposing a portion of the liquid mass to electromagnetic radiation;   (c) vaporizing at least a portion of the liquid mass to propel the liquid mass in a first direction;   (d) redirecting the liquid mass in a second direction that is generally opposite the first direction;   (e) repeating at least steps (b) through (d) to cause the liquid mass to oscillate at an ultrasonic frequency; and   (f) propagating the ultrasonic frequency along a propagation path.