Abstract A continuous wave driven ultrasonic transducer for determining doppler frequency shift in reflected ultrasonic pressure waves in which the transmitter and receiver sections are constructed of a composite core having a plurality of segments of piezoelectric material separated by acoustic suppression material. Also disclosed is a method of reducing acoustic and mechanical cross coupling between piezoelectric transmitter and receiver sections of an ultrasonic transducer by arranging segments of piezoelectric material in a lateral array, and separating the piezoelectric segments with ultrasonic acoustic suppression material to produce a composite transducer core of reduced acoustic and mechanical cross coupling.
A continuous wave Doppler transducer comprising: a transmitter having side-by-side segments of piezoelectric material, ultrasonic wave suppression material interposed between the segments, and means for connecting the segments in parallel; a receiver having side-by-side segments of piezoelectric material, ultrasonic wave suppression material interposed between the segments, and means for connecting the segments in parallel; and a non-conductive separation layer interposed between the transmitter and receiver to acoustically and electrically isolate the receiver from the transmitter.
Claim 2
Dependent Claim
75 words
A continuous wave Doppler transducer comprising: a transmitter having side-by-side segments of piezoelectric material, ultrasonic wave suppression material interposed between the segments, and means for connecting the segments in parallel; a receiver having side-by-side segments of piezoelectric material, ultrasonic wave suppression material interposed between the segments, and means for connecting the segments in parallel; and a non-conductive separation layer interposed between the transmitter and receiver to acoustically and electrically isolate the receiver from the transmitter.
Claim 3
Dependent Claim
16 words
The transducer of claim 1, in which the separation layer is thicker than the suppression material.
Claim 4
Independent Claim
142 words
A method of reducing cross coupling in a continuous wave ultrasound Doppler system having a continuous wave ultrasonic oscillator and an ultrasonic wave receiver for detecting Doppler shift comprising the steps of: arranging a first plurality of segments of piezoelectric material in spaced apart side-by-side relationship; interposing ultrasonic wave suppression material between the first plurality of segments; connecting the first plurality of segments in parallel; arranging a second plurality of segments of piezoelectric material in spaced apart side-by-side relationship; interposing ultrasonic wave suppression material between the second plurality of segments; connecting the second plurality of segments in parallel; interposing a non-conductive separation layer between the transmitter and the receiver to acoustically and electrically isolate the receiver from the transmitter; connecting the oscillator to the first plurality of segments in parallel; and connecting the second plurality of segments in parallel to the receiver.
Claim 5
Independent Claim
142 words
A method of reducing cross coupling in a continuous wave ultrasound Doppler system having a continuous wave ultrasonic oscillator and an ultrasonic wave receiver for detecting Doppler shift comprising the steps of: arranging a first plurality of segments of piezoelectric material in spaced apart side-by-side relationship; interposing ultrasonic wave suppression material between the first plurality of segments; connecting the first plurality of segments in parallel; arranging a second plurality of segments of piezoelectric material in spaced apart side-by-side relationship; interposing ultrasonic wave suppression material between the second plurality of segments; connecting the second plurality of segments in parallel; interposing a non-conductive separation layer between the transmitter and the receiver to acoustically and electrically isolate the receiver from the transmitter; connecting the oscillator to the first plurality of segments in parallel; and connecting the second plurality of segments in parallel to the receiver.