Method and system to prevent depoling of ultrasound transducer

Patent metadata

Field	Value
Publication number	US-11435461-B2
Application number	US-201916516798-A
Country	US
Kind code	B2
Filing date	Jul 19, 2019
Priority date	Jul 19, 2019
Publication date	Sep 6, 2022
Grant date	Sep 6, 2022

Abstract

An ultrasound system, probe and method are provided. The ultrasound system includes a transducer with piezoelectric transducer elements polarized in a poling direction. A bipolar transmit circuit is configured to generate a transmit signal having first and second polarity segments. The first and second polarity segments have corresponding first and second peak amplitudes. A bias generator is configured to generate a bias signal in a direction of the poling direction. The bias signal is combined with the transmit signal to form a biased transmit signal that is shifted in the direction of the poling direction and still includes both of positive and negative voltages over a transmit cycle.

First claim

What is claimed is:

1. An ultrasound system, comprising:
a transducer with piezoelectric transducer elements formed from a slab of piezoelectric material and polarized in a poling direction;
a transmit circuit configured to generate a transmit signal having at least first and second polarity segments, the first and second polarity segments having corresponding first and second peak amplitudes; and
a bias generator configured to generate a bias signal in a direction of the poling direction, wherein the bias signal is combined with the transmit signal to form a biased transmit signal that is shifted in the direction of the poling direction and includes both of positive and negative voltages over a transmit cycle.

2. The ultrasound system of claim 1 , wherein the piezoelectric transducer elements are formed from a single crystal material polarized in the poling direction.

3. The ultrasound system of claim 2 , wherein the single crystal material represents a binary single crystal material.

4. The ultrasound system of claim 1 , wherein the bias signal is a DC voltage that is applied continuously.

5. The ultrasound system of claim 1 , wherein the bias generator is configured to generate the bias signal to have a steady-state voltage of between 2.5V and 10V.

6. The ultrasound system of claim 1 , wherein the bias generator is configured to generate the bias signal to have a steady-state voltage of up to 15% of at least one of the first or second peak amplitudes of the transmit signal.

7. The ultrasound system of claim 1 , wherein the transmit signal includes a series of pulses that repeat, the pulses having a predetermined pulse width to provide an active transmit signal for up to 5% of the transmit cycle, the bias generator configured to apply the bias signal during 90% or more of the transmit cycle.

8. The ultrasound system of claim 1 , wherein the transmit signal includes a series of pulses that repeat, the pulses having a predetermined pulse width to provide an active transmit signal for up to 5% of the transmit cycle, the bias generator configured to apply the bias signal continuously during the transmit cycle.

9. The ultrasound system of claim 1 , further comprising a probe coupled to a distal end of a probe cable, the probe cable including a probe connector at a proximal end of the probe cable, the probe connector configured to be connected to an ultrasound console, the bias generator located within the ultrasound console downstream of the bipolar transmit circuit and before the probe connector.

10. The ultrasound system of claim 1 , further comprising a probe, the bias generator located in the probe.

11. An ultrasound probe, comprising:
a transducer with piezoelectric transducer elements formed from a slab of piezoelectric material and polarized in a poling direction;
a probe connector and a transmit line extending from the probe connector to the transducer, the transmit line configured to convey a transmit signal having at least first and second polarity segments, the first and second polarity segments having corresponding first and second peak amplitudes; and
a bias generator configured to generate a bias signal in a direction of the poling direction, wherein the bias signal is combined with the transmit signal to form a biased transmit signal that is shifted in the direction of the poling direction and includes both of positive and negative voltages over a transmit cycle.

12. The ultrasound probe of claim 11 , wherein the piezoelectric transducer elements are formed from a single crystal material polarized in the poling direction.

13. The ultrasound probe of claim 11 , wherein the bias generator is configured to generate the bias signal to have a steady-state voltage of between 2.5V and 10V.

14. A method, comprising:
utilizing a transducer to transmit ultrasound signals and receive echo ultrasound signals from a region of interest, the transducer including piezoelectric transducer elements formed from a slab of piezoelectric material and polarized in a poling direction;
generating a transmit signal having at least first and second polarity segments, the first and second polarity segments having corresponding first and second peak amplitudes; and
generating a bias signal in a direction of the poling direction; and
combining the bias signal with the transmit signal to form a biased transmit signal that is shifted in the direction of the poling direction and includes both of positive and negative voltages over a transmit cycle.

15. The method of claim 14 , further comprising at least one of:
generating the bias signal to have a steady-state voltage of up to 10V;
generating the bias signal to have a steady-state voltage of up to 6V;
generating the bias signal to have a steady-state voltage of up to 15% of at least one of the first or second peak amplitudes of the transmit signal; or
continuously applying the bias signal during 90% or more of the transmit cycle.

16. The ultrasound system of claim 1 , wherein the biased transmit signal includes a first biased polarity segment that extends in the poling direction and a second biased polarity segment that extends in the non-poling direction.

17. The ultrasound system of claim 1 , wherein the first polarity segment of the transmit signal has a positive voltage and the second polarity segment of the transmit signal has a negative voltage, the biased transmit signal having a first biased polarity segment and a second biased polarity segment, the first biased polarity segment having a positive voltage that is shifted relative to the positive voltage of the first polarity segment, the second biased polarity segment having a negative voltage that is shifted relative to the negative voltage of the second polarity segment.

18. The ultrasound system of claim 1 , wherein the slab of piezoelectric material has a proximal surface and a distal surface, and the proximal and distal surfaces are spaced apart from one another by a thickness of the slab, wherein the thickness of the slab is selected based on a wavelength of sound in the piezoelectric material for a desired center frequency of a useful bandwidth.

19. The ultrasound system of claim 18 , wherein the thickness of the slab is approximately ½ or ¼ of the wavelength of sound in the piezoelectric material for the desired center frequency of the useful bandwidth.

20. The ultrasound system of claim 1 , wherein the slab of piezoelectric material includes multiple kerfs that extend from a proximal surface of the slab through the piezoelectrical material towards a distal surface of the slab, the kerfs separating the piezoelectric transducer elements.

Assignees

• Ge Prec Healthcare Llc

Inventors

• Weichenberger Harald
• Hörl Anton
• Brüstle Reinhold
• Haider Bruno Hans

Classifications

• B06B1/0215

  for generating pulses, e.g. bursts of oscillations, envelopes · CPC title

• A61B8/58

  Testing, adjusting or calibrating the diagnostic device · CPC title

• B06B2201/40

  with testing, calibrating, safety devices, built-in protection, construction details · CPC title

• B06B2201/76

  Medical, dental · CPC title

• B06B1/0622

  on one surface · CPC title