Apparatus and method for driving an ultrasonic transducer

An electromagnetic driving system for an ultrasonic transducer, said system comprising:

• means for exciting said transducer with a first electromagnetic tone burst at a first frequency;
• means for measuring a first response of said transducer to said first tone burst;
• means for exciting said transducer with a second electromagnetic tone burst at a second frequency;
• means for measuring a second response of said transducer to said second tone burst;
• and
• means for selecting a lock-in frequency based on said measured first and second responses.

A method for determining the lock-in frequency of an electromagnetically-driven ultrasonic acoustic transducer, said method comprising the steps of:

• coupling a first signal of a first frequency to said transducer, wherein said first signal is a first electromagnetic tone burst at said first frequency;
• measuring a first response of said transducer to said first signal;
• coupling a second signal of a second frequency to said transducer;
• measuring a second response of said transducer to said second signal;
• and
• selecting a lock-in frequency based on said measured first and second responses.

A method for electromagnetically driving an ultrasonic acoustic transducer, said method comprising the steps of:

• operating in a first mode, wherein the step of operating in said first mode comprises the step of determining a lock-in frequency of said transducer, wherein the step of determining said lock-in frequency comprises the steps of:
• exciting said transducer with an electromagnetic signal swept across a range of frequencies;
• measuring a first response of said transducer to said electromagnetic signal at a first frequency within said range of frequencies;
• measuring a second response of said transducer to said electromagnetic signal at a second frequency within said range of frequencies;
• and
• selecting said lock-in frequency based on said measured first and second responses;
• and
• operating in a second mode, wherein the step of operating in said second mode comprises the step of driving said transducer with an electromagnetic tone burst at said determined lock-in frequency.

An electromagnetic-driving system for an ultrasonic transducer, said system comprising:

• means for exciting said transducer with an electromagnetic signal swept across a range of frequencies;
• means for measuring a first response of said transducer to said electromagnetic signal at a first frequency;
• means for measuring a second response of said transducer to said electromagnetic signal at a second frequency;
• means for selecting a lock-in frequency based on said measured first and second responses;
• means for driving said transducer with an electromagnetic tone burst at said selected lock-in frequency;
• and
• means for receiving acoustic responses from said electromagnetic tone burst at said selected lock-in frequency.

A method for determining the lock-in frequency of an electromagnetically-driven ultrasonic acoustic transducer, said method comprising the steps of:

• exciting said transducer with a tone-burst signal from a tone-burst signal generator at each one of a plurality of frequencies;
• characterizing the frequency response of said transducer to said tone burst signal;
• and
• selecting a lock-in frequency based on said characterized frequency response.