Curved ultrasonic HIFU transducer with pre-formed spherical matching layer

Patent metadata

Field	Value
Publication number	US-10189053-B2
Application number	US-201013508709-A
Country	US
Kind code	B2
Filing date	Nov 3, 2010
Priority date	Nov 9, 2009
Publication date	Jan 29, 2019
Grant date	Jan 29, 2019

Abstract

A curved high intensity focused ultrasound (HIFU) transducer comprising a curved piezoelectric array having opposite convex and concave surfaces, the concave surface being a transmitting surface, and a plurality of acoustic transmission areas, a plurality of electrodes located on the surfaces of the curved piezoelectric array for applying electrical transmit signals to the acoustic transmission areas, and a unitary, continuously formed curved matching layer pre-formed to the desired curvature of the curved transducer array and bonded to the transmitting surface of the curved piezoelectric array which provides acoustic matching and electrical isolation for the transmitting surface of the curved piezoelectric array.

First claim

What is claimed is:

1. A curved high intensity focused ultrasound (HIFU) transducer comprising:
a curved piezoelectric array comprising opposite convex and concave surfaces, the concave surface being a transmitting surface, the curved piezoelectric array further comprising a plurality of acoustic transmission areas;
a plurality of electrodes located on the surfaces of the curved piezoelectric array for applying electrical transmit signals to the acoustic transmission areas; and
a unitary, continuously formed curved matching layer sheet pre-formed to a desired curvature of the curved transducer array and bonded to the entire transmitting surface of the curved piezoelectric array, thereby providing acoustic matching and electrical isolation for the transmitting surface of the curved piezoelectric array, wherein the curved matching layer includes a convex surface bonded to the transmitting surface of the curved piezoelectric array.

2. The curved HIFU transducer of claim 1 , wherein the matching layer further comprises a spherically-curved layer formed by casting or molding.

3. The curved HIFU transducer of claim 2 , wherein the spherically-curved layer comprises a convex spherical surface which matches the curvature of the concave surface of the curved piezoelectric array.

4. The curved HIFU transducer of claim 2 , wherein the spherically curved layer is cast or molded using a concave molding fixture.

5. The curved HIFU transducer of claim 1 , wherein the matching layer further comprises a spherically-curved layer formed by machining a solid matching layer material.

6. The curved HIFU transducer of claim 5 , wherein the solid matching layer material is machined to form a convex spherical surface which matches the curvature of the concave surface of the curved piezoelectric array.

7. The curved HIFU transducer of claim 1 , wherein the curved matching layer further comprises an epoxy loaded with particles which give the matching layer a desired acoustic property.

8. The curved HIFU transducer of claim 1 , wherein the curved matching layer further comprises a thermoplastic resin loaded with particles which give the matching layer a desired acoustic property.

9. The curved HIFU transducer of claim 1 , wherein the curved matching layer further comprises a planar sheet of matching layer material which is heated and formed to the desired curvature.

10. The curved HIFU transducer of claim 9 , wherein the sheet of matching layer material is heated and formed to exhibit a convex spherical surface which matches the curvature of the concave surface of the curved piezoelectric array.

11. The curved HIFU transducer of claim 1 , wherein the curved piezoelectric array further comprises a plurality of piezoelectric tiles which,
when assembled together, forms the piezoelectric array of the desired curvature; and
wherein the pre-formed matching layer is coupled to a fixture onto which the piezoelectric tiles are assembled together and bonded.

12. The curved HIFU transducer of claim 11 , wherein each piezoelectric tile comprises a partially spherical concave surface,
wherein the partially spherical concave surfaces conform to a convex surface of the pre-formed matching layer.

13. The curved HIFU transducer of claim 1 , wherein the matching layer provides a continuous, moisture-impervious barrier between the curved piezoelectric array and the environment in front of the transducer.

14. The curved HIFU transducer of claim 1 , wherein the matching layer further comprises a continuous, electrically-insulating barrier between the curved piezoelectric array and the environment in front of the transducer.

15. The curved HIFU transducer of claim 1 , wherein the curved piezoelectric array comprises ceramic piezoelectric material.

16. The curved HIFU transducer of claim 1 , wherein the curved piezoelectric array comprises a sheet of material comprising holes configured to provide electrical connection from the concave surface to the convex surface.

17. The curved HIFU transducer of claim 1 , wherein the concave surface and the convex surface comprise a conductive material.

18. The curved HIFU transducer of claim 1 , wherein the convex surface of the curved matching layer is covered by a metallized electrode.

19. The curved HIFU transducer of claim 11 , wherein the plurality of tiles have a trapezoidal shape.

20. A curved high intensity focused ultrasound (HIFU) transducer comprising:
a curved piezoelectric array comprising opposite convex and concave surfaces, the concave surface being a transmitting surface, the curved piezoelectric array further comprising a plurality of acoustic transmission areas, wherein the curved piezoelectric array comprises a plurality of piezoelectric tiles each of which comprises posts of piezoelectric material embedded in a non-conductive epoxy, and wherein one or more of the posts of each tile includes a via formed therein, the via comprising non-magnetic conductive material;
a plurality of electrodes located on the surfaces of the curved piezoelectric array for applying electrical transmit signals to the acoustic transmission areas, wherein the plurality of electrodes are provided by metallized layers on the convex and concave surfaces, and wherein the vias formed in the one or more posts connect the metallized layer on the concave surface to the metallized layer on the convex surface; and
a unitary, continuously formed curved matching layer sheet pre-formed to a desired curvature of the curved transducer array and bonded to the entire transmitting surface of the curved piezoelectric array, thereby providing acoustic matching and electrical isolation for the transmitting surface of the curved piezoelectric array, wherein the curved matching layer includes a convex surface bonded to the transmitting surface of the curved piezoelectric array.

Assignees

• Clark Dennis Dean
• Scheirer Barry C
• Manning Ryan
• Wang Haifeng
• Koninklijke Philips Nv

Inventors

• Clark Dennis Dean
• Scheirer Barry C
• Manning Ryan
• Wang Haifeng

Classifications

• B06B1/0637 Primary

  Spherical array · CPC title

• A61N7/02

  Localised ultrasound hyperthermia · CPC title

• G10K11/02

  Mechanical acoustic impedances; Impedance matching, e.g. by horns; Acoustic resonators · CPC title