US4117074A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Monolithic mosaic piezoelectric transducer utilizing trapped energy modes
Assignee: Individual
•
Filing: 1976-08-30
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Granted: 1978-09-26
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Expires: 1996-08-30
Abstract
Abstract A transducer array comprising a large number of separated sets of electrodes plated on a single piezoelectric plate of uniform thickness is described. Each set of electrodes is made to act essentially independently by placing them sufficiently far apart and employing an essentially trapped energy mode.
Inventors
- 👤 Harry F. Tiersten
- 👤 John F. McDonald
- 👤 Pankaj K. Das
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 08:46
CPC Classifications
B; B06; B06B; B06B1/00; B06B1/02; B06B1/06; B06B1/0607; B06B1/0622; B06B1/0629
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
141 words
A transducer element array comprising: a plate of piezoelectric material, means for vibrating said plate to produce vibration thereof including vibration in the thickness extensional mode, a plurality of first electrode means operatively electrically coupled to one surface of said plate in spaced relationship with respect to each other and second electrode means operatively electrically coupled to said other surface of said plate to form with said plurality of first electrode means a plurality of pairs of electrodes, each said pair of electrodes forming a transducer element of the array, said plurality of pairs of electrodes being operatively electrically coupled to said piezoelectric plate so as to provide acoustic energy trapping of the thickness extensional mode of vibration in the unelectroded space between adjacent ones of said pairs of electrodes and to thereby provide acoustic isolation between the adjacent transducer elements.
Claim 2
Dependent Claim
141 words
A transducer element array comprising: a plate of piezoelectric material, means for vibrating said plate to produce vibration thereof including vibration in the thickness extensional mode, a plurality of first electrode means operatively electrically coupled to one surface of said plate in spaced relationship with respect to each other and second electrode means operatively electrically coupled to said other surface of said plate to form with said plurality of first electrode means a plurality of pairs of electrodes, each said pair of electrodes forming a transducer element of the array, said plurality of pairs of electrodes being operatively electrically coupled to said piezoelectric plate so as to provide acoustic energy trapping of the thickness extensional mode of vibration in the unelectroded space between adjacent ones of said pairs of electrodes and to thereby provide acoustic isolation between the adjacent transducer elements.
Claim 3
Dependent Claim
60 words
A transducer array as in claim 1 wherein the frequency ω of the trapped acoustic energy lies between the resonance frequency ω A of an odd thickness extensional mode of vibration of the unelectroded region of the plate and the resonance frequency ω C of the corresponding odd thickness extensional mode of vibration of the electroded region of the plate.
Claim 4
Dependent Claim
35 words
A transducer array as in claim 2 wherein the frequency ω A is higher than the frequency ω B of the pertinent even thickness extensional mode of vibration of the unelectroded space of the plate.
Claim 5
Dependent Claim
15 words
A transducer array wherein said plate of piezoelectric material is of substantially uniform thickness throughout.
Claim 6
Dependent Claim
15 words
A transducer array wherein said plate of piezoelectric material is of substantially uniform thickness throughout.
Claim 7
Dependent Claim
16 words
A transducer array as in claim 1 wherein said second electrode means comprises a continuous member.
Claim 8
Dependent Claim
50 words
A transducer array as in claim 1 wherein said second electrode means comprises a plurality of means each of the same general shape as the respective means of the first plurality of electrode means, each of said second electrode means located opposite a corresponding one of said first electrode means.
Claim 9
Dependent Claim
19 words
A transducer array as in claim 1 wherein each of said first electrode means is of generally circular shape.
Claim 10
Dependent Claim
24 words
A transducer array as in claim 1 wherein said means for exciting said piezoelectric plate excites the same to produce a thickness extension mode.
Claim 11
Dependent Claim
25 words
A transducer array as in claim 1 wherein said means for exciting said plate comprises means for coupling mechanical energy to said second electrode means.
Claim 12
Dependent Claim
19 words
A transducer array as in claim 9 further comprising means for coupling electrical energy from said second electrode means.
Claim 13
Dependent Claim
24 words
A transducer array as in claim 1 wherein said means for exciting said plate comprises, means for supplying electrical energy to pairs of electrodes.
Claim 14
Dependent Claim
14 words
A transducer as in claim 11 further comprising means for coupling mechanical energy therefrom.
Claim 15
Dependent Claim
17 words
A transducer array as in claim 1 wherein ω A > ω C > ω B .
Claim 16
Dependent Claim
15 words
A transducer array as in claim 1 wherein said piezoelectric material is a polarized ceramic.
Claim 17
Dependent Claim
13 words
A transducer array as in claim 14 wherein said polarized ceramic is PZT-7A.
References Cited (Backward Citations)
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US3891872A
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US3971962A
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US3961210A
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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) | 1981-09-25 | 1982-03-27 | 1982-09-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-09-25 | 1986-03-27 | 1986-09-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-09-25 | 1990-03-27 | 1990-09-26 | $7700.00 | Window Closed / Lapsed |