Curved ultrasonic HIFU transducer formed by tiled segments

• US 9,393,597 B2
• Filed: 11/03/2010
• Issued: 07/19/2016
• Est. Priority Date: 11/09/2009
• Status: Active Grant

• Current Assignee: Koninklijke Philips N.V.
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Clark, Dennis Dean
• Primary Examiner(s): Chen, Tse
• Assistant Examiner(s): Ip, Jason
• Application Number:
  US13/508,717
• Publication Number:
  US 20130012841A1
• Time in Patent Office: 2,085 Days
• Field of Search: 600/437
• US Class Current: 1/1
• CPC Class Codes: A61N 7/02 Localised ultrasound hyperthermia hyperthermia in general A61F7/00
• CPC Class Codes: B06B 1/0637 Spherical array

Abstract

A curved high intensity focused ultrasound (HIFU) transducer comprising a plurality of curved composite ceramic piezoelectric tiles having opposite convex and concave surfaces, each tile having electrodes on the surfaces electrically coupled to the composite ceramic piezoelectric material, and a plurality of acoustic transmission areas located on each tile and actuated through electrodes on the convex surface, the transmission areas and electrodes being acoustically separated from surrounding areas by cuts into the composite ceramic piezoelectric material, the plurality of tiles fitting together to form a substantially continuous curved composite piezoelectric surface which transmits HIFU acoustic energy.

Claims

1. A curved high intensity focused ultrasound (HIFU) transducer comprising:

a plurality of separate curved composite ceramic piezoelectric tiles having opposite convex and concave surfaces, wherein the composite ceramic piezoelectric tiles comprise a layer of ceramic piezoelectric posts embedded in epoxy,

each tile of the plurality of tiles having electrodes on the surfaces electrically coupled to the composite ceramic piezoelectric material, and

a plurality of acoustic transmission areas located on each tile of the plurality of tiles and actuated through electrodes on the convex surface, the transmission areas and electrodes being acoustically separated from surrounding areas by cuts into the composite ceramic piezoelectric material,

the plurality of tiles each coupled to a support frame comprising ribs that separate the tiles from one another, wherein the plurality of tiles form a curved composite piezoelectric surface configured to transmit HIFU acoustic energy.

2. The curved HIFU transducer of claim 1, wherein the layer of ceramic piezoelectric posts embedded in epoxy forms a 1:

3 composite matrix.

3. The curved HIFU transducer of claim 2, wherein each acoustic transmission area further comprises a plurality of ceramic piezoelectric posts of a composite matrix.

4. The curved HIFU transducer of claim 1, wherein the acoustic transmission areas are acoustically separated by peripheral cuts extending at least halfway through the piezoelectric material.

5. The curved HIFU transducer of claim 1, further comprising at least one acoustic reception area located on each tile and actuated through an electrode on the convex surface.

6. The curved HIFU transducer of claim 1, wherein the transmission areas on a tile are surrounded by an electrode area which is coupled to a reference potential.

7. The curved HIFU transducer of claim 6, wherein the electrode on the concave surface further comprises a metalized layer coupled to a reference potential.

8. The curved HIFU transducer of claim 7, wherein the electrode on the concave surface is coupled to a reference potential electrode area on the convex surface by a conductive via extending through the composite ceramic piezoelectric tile.

9. The curved HIFU transducer of claim 1, wherein the concave surface further comprises a patient-facing acoustic emission surface.

10. The curved HIFU transducer of claim 1, wherein the plurality of tiles are fitted together over and bonded to a curved matching layer having a convex curvature matching the concave curvature of the composite piezoelectric surface.

11. The curved HIFU transducer of claim 1, wherein the piezoelectric tiles are each separate tiles having one of a pie-slice shape or a trapezoidal shape and a spherical curvature to fit together with other tiles of the plurality of tiles to form the substantially continuous curved composite piezoelectric surface.

12. The curved HIFU transducer of claim 1, wherein the piezoelectric tiles are each separate tiles having a trapezoidal shape and a spherical curvature to fit together with other tiles of the plurality of tiles to form the substantially continuous curved composite piezoelectric surface, wherein the tiles define a central space in the center of the transducer when the tiles are fitted together, wherein a disk-shaped spherical tile is located in the central space.

13. The curved HIFU transducer of claim 1, wherein the piezoelectric tiles are each separate tiles having a trapezoidal shape and a spherical curvature to fit together with other tiles of the plurality of tiles to form the substantially continuous curved composite piezoelectric surface, wherein the tiles define a central space in the center of the transducer when the tiles are fitted together, wherein a cooling element is located in the central space.

14. The curved HIFU transducer of claim 2, wherein the 1:

3 composite piezoelectric posts and the cuts into the composite ceramic piezoelectric material surrounding the acoustic transmission areas both act to reduce lateral acoustic transmission through the piezoelectric material.

15. The curved HIFU transducer of claim 1, wherein the opposite convex and concave surfaces are metalized by a conductive material.

16. The curved HIFU transducer of claim 15, wherein the conductive material is non-magnetic.

17. The curved HIFU transducer of claim 1, wherein each of the plurality of tiles is accessible between the ribs.

18. The curved HIFU transducer of claim 1, further comprising a plurality of circuit boards attached in a spaced relation opposite the convex surfaces of the tiles using the support frame.

19. The curved HIFU transducer of claim 18, wherein the plurality of circuit boards are electrically coupled to the tiles using compliant metallic contacts spanning the distance between the circuit boards and the tiles.

20. A curved high intensity focused ultrasound (HIFU) transducer comprising:

a plurality of separate curved composite ceramic piezoelectric tiles having opposite convex and concave surfaces, wherein the composite ceramic piezoelectric tiles comprise a layer of ceramic piezoelectric posts embedded in epoxy, each tile of the plurality of tiles having electrodes on the opposite convex and concave surfaces, the electrodes electrically coupled to the composite ceramic piezoelectric material, a plurality of acoustic transmission areas located on each tile of the plurality of tiles and actuated through electrodes on the convex surface, the transmission areas and electrodes being acoustically separated from surrounding areas by cuts into the composite ceramic piezoelectric material;

a continuous curved matching layer, wherein the plurality of tiles are fitted over and bonded to a convex side of the continuous curved matching layer to form a substantially continuous concave surface which transmits HIFU acoustic energy;

a support frame attached to a convex side of the plurality of tiles, the support frame comprising ribs that separate the tiles from one another; and

a plurality of circuit boards mounted in a spaced relation opposite the convex side of the plurality of tiles using the support frame.