Multiple aperture ultrasound array alignment fixture

• US 8,473,239 B2
• Filed: 04/14/2010
• Issued: 06/25/2013
• Est. Priority Date: 04/14/2009
• Status: Active Grant

• Current Assignee: Maui Imaging, Inc.
• Original Assignee: Maui Imaging, Inc.
• Inventors: Specht, Donald F., Brewer, Kenneth D., Smith, David M., Adam, Sharon L., Lunsford, John P.
• Primary Examiner(s): Lau, Tung S
• Application Number:
  US12/760,327
• Publication Number:
  US 20100268503A1
• Time in Patent Office: 1,168 Days
• Field of Search: 702/100
• US Class Current: 702/100
• CPC Class Codes: A61B 8/00 Diagnosis using ultrasonic, sonic or infrasonic waves imaging of objects using sonar G01S15/00
• CPC Class Codes: A61B 8/0883 for diagnosis of the heart
• CPC Class Codes: A61B 8/42 Details of probe positioning or probe attachment to the patient
• CPC Class Codes: A61B 8/4218 characterised by articulated arms
• CPC Class Codes: A61B 8/4444 related to the probe
• CPC Class Codes: A61B 8/4477 using several separate ultrasound transducers or probes
• CPC Class Codes: A61B 8/587 Calibration phantoms models for medical purposes G09B23/28
• CPC Class Codes: G01S 15/8913 using separate transducers for transmission and reception
• CPC Class Codes: G01S 7/5205 Means for monitoring or calibrating
• CPC Class Codes: Y10T 29/49778 with aligning, guiding, or instruction

Abstract

Increasing the effective aperture of an ultrasound imaging probe by including more than one probe head and using the elements of all of the probes to render an image can greatly improve the lateral resolution of the generated image. In order to render an image, the relative positions of all of the elements must be known precisely. A calibration fixture is described in which the probe assembly to be calibrated is placed above a test block and transmits ultrasonic pulses through the test block to an ultrasonic sensor. As the ultrasonic pulses are transmitted though some or all of the elements in the probe to be tested, the differential transit times of arrival of the waveform are measured precisely. From these measurements the relative positions of the probe elements can be computed and the probe can be aligned.

Claims

1. A system for measuring and aligning the positions of transducer elements in a multi-aperture ultrasound probe, comprising:

an alignment assembly configured to hold a plurality of transducer elements;

a test block positioned adjacent to the alignment assembly;

an ultrasonic sensor disposed in the test block and configured to receive ultrasonic pulses through the test block from at least one of the plurality of transducer elements; and

a controller configured to evaluate data from the ultrasonic sensor and provide transducer calibration data.

2. The system of claim 1 wherein the test block comprises a tank filled with a liquid having a known speed of sound.

3. The system of claim 1 wherein the test block comprises a tank filled with a gelatinous material having known speed of sound.

4. The system of claim 1 wherein the test block comprises a solid block having a known speed of sound.

5. The system of claim 1 further comprising a signal generator configured to excite at least one of the plurality of transducer elements to transmit ultrasonic pulses.

6. The system of claim 1 wherein the alignment assembly comprises an automated alignment assembly configured to automatically align the plurality of transducer elements based on the transducer calibration data from the controller.

7. The system of claim 1 wherein the alignment assembly comprises a manual alignment assembly.

8. The system of claim 1 wherein the controller runs algorithms configured to detect relative elapsed times to a plurality of receiving transducer elements disposed on the ultrasonic sensor.

9. The system of claim 1 wherein the controller runs algorithms configured to compute complete transit times from at least one of the plurality of transducer elements to a plurality of receiving transducer elements disposed on the ultrasonic sensor.

10. The system of claim 1 wherein the controller runs algorithms configured to compute the relative position of the plurality of transducer elements based on the transducer calibration data.

11. The system of claim 1 further comprising a graphical user interface configured to display the transducer calibration data.

12. The system of claim 1 wherein the alignment assembly is configured to hold a probe containing the plurality of transducer elements.

13. The system of claim 1 wherein the ultrasonic sensor includes a plurality of receiving transducer elements.

14. The system of claim 1 wherein the controller is configured to digitize and store the received ultrasonic pulses.

15. The method of claim 1 wherein the ultrasonic sensor comprises a hydrophone.

16. The method of claim 1 wherein the ultrasonic sensor is separate from the alignment assembly.

17. The system of claim 5 wherein the signal generator is configured to excite the plurality of transducer elements with a spread spectrum waveform.

18. The system of claim 5 wherein the signal generator is configured to excite at least one of the plurality of transducer elements with a chirp waveform.

19. The system of claim 6 wherein the alignment assembly comprises at least one stepper motor and a stepper motor controller.

20. The system of claim 7 wherein the manual alignment assembly includes manual controls configured to manipulate the plurality of transducer elements in the x, y, and z axes.

21. The system of claim 19 wherein the stepper motor controller drives the at least one stepper motor to align the transducer element.

22. A system for measuring and reporting the positions of transducer elements in a multi-aperture ultrasound probe, comprising:

a calibration assembly;

a plurality of transducer elements disposed in the calibration assembly;

a test block positioned adjacent to the plurality of transducer elements;

an ultrasonic sensor disposed in the test block and configured to receive ultrasonic pulses through the test block from at least one of the plurality of transducer elements; and

a controller configured to evaluate data from the ultrasonic sensor and provide transducer calibration data for at least one of the plurality of transducer elements.

23. The system of claim 22 wherein the test block comprises a tank filled with a liquid having a known speed of sound.

24. The system of claim 22 wherein the test block comprises a tank filled with a gelatinous material having known speed of sound.

25. The system of claim 22 wherein the test block comprises a solid block having a known speed of sound.

26. The system of claim 22 wherein the calibration assembly is configured to automatically determine the relative positions of the plurality of transducer elements based on the transducer calibration data from the controller.

27. The system of claim 22 wherein the controller runs algorithms configured to detect relative elapsed times to a plurality of receiving transducer elements disposed on the ultrasonic sensor.

28. The system of claim 27 wherein the controller runs algorithms configured to compute the relative position of the plurality of transducer elements based on the transducer calibration data.

29. The system of claim 22 further comprising a graphical user interface configured to display the transducer calibration data.

30. The system of claim 22 further comprising memory in the multi-aperture ultrasound probe configured to record the transducer calibration data.

31. The method of claim 22 wherein the ultrasonic sensor comprises a hydrophone.

32. The method of claim 22 wherein the ultrasonic sensor is separate from the plurality of transducer elements.

33. The system of claim 27 wherein the controller runs algorithms configured to compute complete transit times from the relative elapsed times.

34. A method for measuring and aligning the positions of transducer elements in a multi-aperture ultrasound probe, comprising:

mounting a plurality of transducer elements in an alignment assembly;

transmitting ultrasonic pulses through a test block from at least one of the plurality of transducer elements;

receiving the ultrasonic pulses with an ultrasonic sensor disposed in the test block; and

evaluating the received ultrasonic pulses from the ultrasonic sensor with a controller to provide transducer calibration data for at least one of the plurality of transducer elements.

35. The method of claim 34 further comprising aligning the plurality of transducer elements based on the transducer calibration data.

36. The method of claim 35 further comprising automatically aligning the plurality of transducer elements based on the transducer calibration data.

37. The method of claim 35 further comprising manually aligning the plurality of transducer elements based on the transducer calibration data.

38. The method of claim 35 wherein the controller runs an algorithm configured to detect relative elapsed times to a plurality of receiving transducer elements disposed on the ultrasonic sensor.

39. The method of claim 35 wherein the controller runs an algorithm configured to compute complete transit times from the transducer element to a receiving transducer element disposed on the ultrasonic sensor.

40. The method of claim 35 wherein the controller runs an algorithm configured to compute the relative position of the plurality of transducer elements based on the transducer calibration data.