US4464639A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ferroelectric surface acoustic wave devices
Assignee: Boeing North American Inc
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Filing: 1982-09-17
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Granted: 1984-08-07
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Expires: 2002-09-17
Abstract
Abstract Disclosed is a surface acoustic wave filter based on a ferroelectric crystal having a plurality of ordered domains of alternating polarity. An output interdigital transducer, with at least one pair of electrodes, is deposited on a surface of the crystal so that each of the electrode pairs corresponds to one of the ordered domains, and an input interdigital transducer is oriented on the surface to direct a surface acoustic wave toward the output transducer. In addition, sources of both positive and negative electrical potential may be provided, with a switch for each output electrode pair to selectably apply either the positive or the negative potential to that pair.
Inventors
- 👤 Edward J. Staples
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 06:07
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/46; H03H9/64; H03H9/6403; H03H9/02; H03H9/02535; H03H9/02543; Y; Y10; Y10T; Y10T29/00; Y10T29/42
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
70 words
A surface acoustic wave device, comprising: a ferroelectric strontium barium niobate crystal having a plurality of ordered domains of alternating polarity; an output interdigital transducer, including at least one pair of electrodes, disposed on a surface of said crystal, each of said electrode pairs corresponding to one of said domains; an input interdigital transducer disposed on said surface and oriented to direct a surface acoustic wave toward said output transducer.
Claim 2
Dependent Claim
70 words
A surface acoustic wave device, comprising: a ferroelectric strontium barium niobate crystal having a plurality of ordered domains of alternating polarity; an output interdigital transducer, including at least one pair of electrodes, disposed on a surface of said crystal, each of said electrode pairs corresponding to one of said domains; an input interdigital transducer disposed on said surface and oriented to direct a surface acoustic wave toward said output transducer.
Claim 3
Dependent Claim
102 words
A surface acoustic wave device, comprising: a ferroelectric strontium barium niobate crystal having a plurality of ordered domains of alternating polarity; an interdigital transducer, including at least one pair of electrodes, disposed on a surface of said crystal, each of said electrode pairs corresponding to one of said domains; a source of positive electrical potential; a source of negative electrical potential; and a switch for each of said electrode pairs to selectably apply either said positive source or said negative source across each pair to establish a spatially alternating electric field in said surface and thereby create said plurality of ordered domains.
Claim 4
Dependent Claim
102 words
A surface acoustic wave device, comprising: a ferroelectric strontium barium niobate crystal having a plurality of ordered domains of alternating polarity; an interdigital transducer, including at least one pair of electrodes, disposed on a surface of said crystal, each of said electrode pairs corresponding to one of said domains; a source of positive electrical potential; a source of negative electrical potential; and a switch for each of said electrode pairs to selectably apply either said positive source or said negative source across each pair to establish a spatially alternating electric field in said surface and thereby create said plurality of ordered domains.
Claim 5
Dependent Claim
116 words
A surface acoustic wave filter, comprising: a ferroelectric strontium barium niobate crystal; an output interdigital transducer, including at least one pair of output electrodes, disposed on a surface of said crystal; an input interdigital transducer, including at least one pair of input electrodes, disposed on said surface and oriented to direct a surface acoustic wave toward said output transducer; a source of positive electrical potential; a source of negative electrical potential; and a switch for each of said output electrode pairs to selectably apply either said positive source or said negative source across each pair to establish a spatially alternating electric field in said surface and thereby create a plurality of ordered domains in said surface.
Claim 6
Dependent Claim
116 words
A surface acoustic wave filter, comprising: a ferroelectric strontium barium niobate crystal; an output interdigital transducer, including at least one pair of output electrodes, disposed on a surface of said crystal; an input interdigital transducer, including at least one pair of input electrodes, disposed on said surface and oriented to direct a surface acoustic wave toward said output transducer; a source of positive electrical potential; a source of negative electrical potential; and a switch for each of said output electrode pairs to selectably apply either said positive source or said negative source across each pair to establish a spatially alternating electric field in said surface and thereby create a plurality of ordered domains in said surface.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-08-07 | 1988-02-06 | 1988-08-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-08-07 | 1992-02-06 | 1992-08-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-08-07 | 1996-02-06 | 1996-08-07 | $7700.00 | Window Closed / Lapsed |