Patent US570590A successfully refreshed from Google Patents.
US4401910A
Expired / Lapsed
US
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Multi-focus spiral ultrasonic transducer
Assignee: Analogic Corp
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Filing: 1981-11-30
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Granted: 1983-08-30
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Expires: 2001-11-30
Abstract
Abstract An ultrasonic transducer providing a plurality of different focal lengths within a unitary structure and comprising a piezoelectric element having a cylindrical spiral surface with respective sections of the spiral surface providing respective different focal lengths. Each section of the spiral surface can include electrodes in the form of a Fresnel zone pattern to provide focusing in the orthogonal dimension to the spiral axis.
Inventors
- 👤 Henry P. Beerman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:23
CPC Classifications
B; B06; B06B; B06B1/00; B06B1/02; B06B1/06; B06B1/0688; B06B1/0692; G; G10; G10K; G10K11/00; G10K11/18; G10K11/26; G10K11/32; Y; Y10; Y10S; Y10S310/00; Y10S310/80
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
64 words
An ultrasonic transducer comprising: a piezoelectric element having a cylindrical spiral surface, the surface having respective sections along the length thereof, each of a different focal length; a rear electrode provided on the rear surface of the piezoelectric element; a front electrode provided on the front surface of each section of the piezoelectric element; and means for supporting the piezoelectric element and electrode layers.
Claim 2
Dependent Claim
64 words
An ultrasonic transducer comprising: a piezoelectric element having a cylindrical spiral surface, the surface having respective sections along the length thereof, each of a different focal length; a rear electrode provided on the rear surface of the piezoelectric element; a front electrode provided on the front surface of each section of the piezoelectric element; and means for supporting the piezoelectric element and electrode layers.
Claim 3
Dependent Claim
63 words
The transducer of claim 1 wherein the front electrode for each section includes: a one-dimensional Fresnel zone pattern on the front surface of the section of the spiral surface and disposed along an axis transverse to the spiral axis; each section having a Fresnel zone pattern of different focal length corresponding to the focal length of the associated section of the spiral surface.
Claim 4
Dependent Claim
27 words
The transducer of claim 1 wherein the Fresnel zone pattern for each section of the spiral surface is symmetric about the center line of the spiral surface.
Claim 5
Dependent Claim
19 words
The transducer of claim 1 wherein the piezoelectric element is a piezoelectric film disposed in a cylindrical spiral path.
Claim 6
Dependent Claim
13 words
The transducer of claim 4 wherein the piezoelectric film is of polyvinylidine fluoride.
Claim 7
Dependent Claim
146 words
An ultrasonic transducer comprising: a piezoelectric element having a cylindrical spiral surface, the surface having respective sections along the length thereof, each of a different focal length, the element having a front surface and a rear surface; a rear electrode provided on the rear surface of the piezoelectric element; a front electrode provided on the front surface of each section of the piezoelectric element; the front electrode for each section including a one dimensional Fresnel zone pattern on the front surface of the section of the spiral surface and disposed along an axis transverse to the spiral axis; and each section having a Fresnel zone pattern of different focal length corresponding to the focal length of the associated section of the spiral surface, the Fresnel zone pattern for each section being provided by an array of spaced electrode areas, the array extending along the spiral axis.
Claim 8
Dependent Claim
146 words
An ultrasonic transducer comprising: a piezoelectric element having a cylindrical spiral surface, the surface having respective sections along the length thereof, each of a different focal length, the element having a front surface and a rear surface; a rear electrode provided on the rear surface of the piezoelectric element; a front electrode provided on the front surface of each section of the piezoelectric element; the front electrode for each section including a one dimensional Fresnel zone pattern on the front surface of the section of the spiral surface and disposed along an axis transverse to the spiral axis; and each section having a Fresnel zone pattern of different focal length corresponding to the focal length of the associated section of the spiral surface, the Fresnel zone pattern for each section being provided by an array of spaced electrode areas, the array extending along the spiral axis.
Claim 9
Dependent Claim
22 words
The transducer of claim 6 wherein the electrode areas of each section are electrically interconnected to provide a predetermined capacitance and reactance.
Claim 10
Dependent Claim
168 words
An ultrasonic transducer comprising: a piezoelectric element having a cylindrical spiral surface, the surface having respective sections along the length thereof, each of a different focal length, the element having a front surface and a rear surface; a rear electrode provided on the rear surface of the piezoelectric element; a front electrode provided on the front surface of each section of the piezoelectric element; means for supporting the piezoelectric element and electrode layers; the front electrode for each section including a one-dimensional Fresnel zone pattern on the front surface of the section of the spiral surface and disposed along an axis transverse to the spiral axis, each section having a Fresnel zone pattern of different focal length corresponding to the focal length of the associated section of the spiral surface; wherein the Fresnel zone pattern includes electrode areas, each extending along the longitudinal axis of the spiral surface, the pattern extending across the transverse axis, the electrode area being of defined width and spacing for the respective sections.
Claim 11
Dependent Claim
168 words
An ultrasonic transducer comprising: a piezoelectric element having a cylindrical spiral surface, the surface having respective sections along the length thereof, each of a different focal length, the element having a front surface and a rear surface; a rear electrode provided on the rear surface of the piezoelectric element; a front electrode provided on the front surface of each section of the piezoelectric element; means for supporting the piezoelectric element and electrode layers; the front electrode for each section including a one-dimensional Fresnel zone pattern on the front surface of the section of the spiral surface and disposed along an axis transverse to the spiral axis, each section having a Fresnel zone pattern of different focal length corresponding to the focal length of the associated section of the spiral surface; wherein the Fresnel zone pattern includes electrode areas, each extending along the longitudinal axis of the spiral surface, the pattern extending across the transverse axis, the electrode area being of defined width and spacing for the respective sections.
Claim 12
Dependent Claim
29 words
The transducer of claim 8 wherein the Fresnel zone pattern for each section of the spiral surface is of different width and spacing to provide a respective focal length.
Claim 13
Dependent Claim
13 words
The transducer of claim 9 wherein the supporting means includes acoustic damping material.
Claim 14
Dependent Claim
28 words
The transducer of claim 9 wherein the supporting means includes a block of acoustic damping material having a cylindrical spiral surface on which the piezoelectric element is disposed.
Claim 15
Dependent Claim
13 words
The transducer of claim 11 wherein the piezoelectric element has a uniform width.
Claim 16
Dependent Claim
62 words
An ultrasonic transducer comprising: a housing; a piezoelectric element supported in the housing and having a cylindrical spiral surface, the surface having respective sections along the length thereof, each of a diffrent focal length; a front electrode provided on the front surface of each section of the piezoelectric element; and a rear electrode provided on the rear surface of the piezoelectric element.
Claim 17
Dependent Claim
62 words
An ultrasonic transducer comprising: a housing; a piezoelectric element supported in the housing and having a cylindrical spiral surface, the surface having respective sections along the length thereof, each of a diffrent focal length; a front electrode provided on the front surface of each section of the piezoelectric element; and a rear electrode provided on the rear surface of the piezoelectric element.
Claim 18
Dependent Claim
63 words
The transducer of claim 13 wherein the front electrode for each section includes: a one-dimensional Fresnel zone pattern on the front surface of the section of the spiral surface and disposed along an axis transverse to the spiral axis; each section having a Fresnel zone pattern of different focal length corresponding to the focal length of the associated section of the spiral surface.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-08-29 | 1987-02-28 | 1987-08-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-08-29 | 1991-02-28 | 1991-08-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-08-29 | 1995-02-28 | 1995-08-30 | $7700.00 | Window Closed / Lapsed |