Broadband phased array transducer design with frequency controlled two dimension capability and methods for manufacture thereof
First Claim
1. A transducer for producing an ultrasound beam upon excitation comprising:
- a plurality of piezoelectric elements, each of said elements comprising a thickness at at least a first point on a surface facing a region of examination being less than a thickness at at least a second point on said surface, said surface being generally non-planar, said surface having a radius of curvature along an elevation direction which is different than a radius of curvature along an azimuthal direction.
3 Assignments
0 Petitions
Accused Products
Abstract
There is provided a transducer array with a plurality of piezoelectric elements having a minimum and maximum thickness. In one embodiment, the maximum thickness is less than or equal to 140 percent of the minimum thickness. In an alternate embodiment, the maximum thickness is greater than 140 percent of the minimum thickness and the transducer array is capable of simulating the excitation of a wider aperture two-dimensional transducer array. One or more matching layers may be used to further increase bandwidth performance. In addition, a two crystal transducer element as well as a composite transducer structure may be formed using the principles of this invention.
-
Citations
57 Claims
-
1. A transducer for producing an ultrasound beam upon excitation comprising:
a plurality of piezoelectric elements, each of said elements comprising a thickness at at least a first point on a surface facing a region of examination being less than a thickness at at least a second point on said surface, said surface being generally non-planar, said surface having a radius of curvature along an elevation direction which is different than a radius of curvature along an azimuthal direction. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14)
-
15. An ultrasound transducer comprising:
-
a plurality of piezoelectric elements each comprising a front portion facing a region of examination, a back portion, two side portions, and a thickness between said front portion and said back portion; said thickness being greater at each of said side portions than between said side portions; said front portion being generally non-planar, said front portion having a radius of curvature along an elevation direction which is different than a radius of curvature along an azimuthal direction; wherein each of said elements produces an ultrasound beam having a width which varies inversely as to a frequency of excitation of a given element. - View Dependent Claims (16, 17, 18)
-
-
19. A transducer for producing an ultrasound beam upon excitation at a given frequency comprising:
a piezoelectric element comprising a front portion facing a region of examination being generally non-planar, said front portion having a radius of curvature along an elevation direction which is different than a radius of curvature along an azimuthal direction, wherein said element operates at a dominant fundamental harmonic frequency and a dominant second harmonic frequency. - View Dependent Claims (20)
-
21. An ultrasound transducer comprising:
a plano-concave piezoelectric element comprising a curved front surface facing a region of examination, a back surface, two sides, and a thickness between said front surface and said back surface, said front surface comprising a radius of curvature approximated by the equation h/2+(w2 /8h), where h is the difference between a minimum and maximum thickness of said transducer element and w is the width of said transducer element between said sides, wherein said element produces an ultrasound beam having a width which varies inversely as to a frequency of excitation of said element. - View Dependent Claims (22)
-
23. An array-type ultrasonic transducer comprising:
-
a plurality of transducer elements disposed adjacent to one another, each of said elements comprising a front portion facing a region of examination, a back portion, two side portions, and a transducer thickness between said front portion and said back portion, said transducer thickness being a maximum thickness at said side portions and a minimum thickness between said side portions, said maximum thickness being less than or equal to 140% of said minimum thickness. - View Dependent Claims (24, 25, 26)
-
-
27. An ultrasound system for generating an image comprising:
-
transmit circuitry for transmitting electrical signals to a transducer probe; a transducer probe for transmitting an ultrasound beam produced by a given frequency excitation and for receiving pressure waves reflected from a body being examined; receive circuitry for processing the signals received by said transducer probe; a display for providing an image of an object being observed; said transducer probe comprising a plurality of piezoelectric elements, each of said elements comprising a thickness at at least a first point on a surface facing a region of examination being less than a thickness at at least a second point on said surface, said surface being generally non-planar and having a radius of curvature along an elevation direction which is different than a radius of curvature along an azimuthal direction, wherein said ultrasound beam has a width which is related to said frequency of excitation of said element. - View Dependent Claims (28, 29)
-
-
30. A method of making a transducer for producing an ultrasound beam upon excitation comprising the steps of:
-
forming a plurality of piezoelectric elements, each of said elements comprising a thickness at at least one point on a surface facing a region of examination being less than a thickness at at least one other point on said surface such that an aperture of said ultrasound beam varies inversely as to a frequency of excitation of each of said elements, said surface being generally non-planar and having a radius of curvature along an elevation direction which is different than a radius of curvature along an azimuthal direction; and establishing an electric field through at least one portion of each of said elements. - View Dependent Claims (31, 32, 33, 34, 35)
-
-
36. A method of making a transducer for producing an ultrasound beam upon excitation comprising the steps of:
-
forming a plurality of transducer elements disposed adjacent to one another, each of said elements comprising a front portion facing a region of examination, a back portion, two side portions, and a transducer thickness between said front portion and said back portion, said transducer thickness being a maximum thickness at said side portions and a minimum thickness between said side portions, said maximum thickness being less than or equal to 140% of said minimum thickness; and establishing an electric field through at least one portion of each of said elements. - View Dependent Claims (37, 38)
-
-
39. A method of producing an image in response to excitation of a transducer for generating an ultrasound beam comprising the steps of:
-
providing electrical signals to a transducer probe for transmitting a beam of ultrasound pressure waves to a body being examined such that said transducer probe includes a plurality of piezoelectric elements, each of said elements comprising a thickness at at least one point on a surface facing a region of examination being less than a thickness at at least one other point on said surface, said surface being generally non-planar and having a radius of curvature along an elevation direction which is different than a radius of curvature along an azimuthal direction, and an aperture of an ultrasound beam varying inversely as to a frequency of excitation of said element; receiving pressure waves reflected from said body and converting said received pressure waves into received electrical signals; processing said received electrical signals; and displaying the object being observed. - View Dependent Claims (40, 41, 42, 43)
-
-
44. A transducer having bandwidth activation energy for producing an ultrasound beam comprising:
-
a plurality of piezoelectric elements each comprising a front portion facing a region of examination, a back portion, two side portions, and a thickness between said front portion and said back portion; said thickness being a maximum value LMAX near each of said side portions and a minimum value LMIN between said side portions; said front portion being generally non-planar; wherein an increase in said bandwidth activation energy is approximated by the ratio LMAX/LMIN. - View Dependent Claims (45, 46, 47)
-
-
48. A transducer for producing an ultrasound beam upon excitation comprising:
-
a plurality of piezoelectric elements, each of said elements comprising a thickness at a first point on a surface facing a region of examination being less than a thickness at a second point on said surface, said surface being generally non-planar, said thickness at said second point being less than or equal to 140% of said thickness at said first point; wherein each of said elements produces an ultrasound beam having a width which varies inversely as to a frequency of excitation of a given element. - View Dependent Claims (49, 50)
-
-
51. A transducer for producing an ultrasound beam upon excitation comprising:
-
a plurality of piezoelectric elements each comprising a front portion facing a region of examination, a back portion, two side portions, a center portion between said side portions, and a thickness between said front portion and said back portion, said thickness being greater at each of said side portions than between said side portions, said front portion being generally non-planar and having a radius of curvature along an elevation direction which is different than a radius of curvature along an azimuthal direction; a plurality of first electrodes, each one of said first electrodes disposed on said back portion of a corresponding one of said piezoelectric elements; a plurality of second electrodes, each one of said second electrodes disposed between a body being examined and said front portion of a corresponding one of said piezoelectric elements; wherein an electric field between said first and second electrodes is greater at said center portion than said side portions. - View Dependent Claims (52, 53, 54, 55, 56, 57)
-
Specification