US3975697A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Surface acoustic wave devices
Assignee: UK Secretary of State for Defence
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Filing: 1975-08-01
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Granted: 1976-08-17
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Expires: 1995-08-01
Abstract
Abstract A surface acoustic wave device comprises a substrate able to support surface acoustic waves, an input transducer for launching surface acoustic waves along a first track on the substrate, an output transducer for receiving surface acoustic waves from a second track on the substrate, and first and second reflective array structures arranged to reflect surface acoustic waves from the first track into the second track, the first and second reflective array structures each comprising numerous reflecting strips or grooves arranged parallel to one another in echalon across the first and second tracks respectively. Varying the lengths of the reflecting elements provides weighting of signals passing through the device, and varying the spacing between the reflecting elements provides pulse compression or expansion with a frequency sweep.
Inventors
- 👤 Edward George Sydney Paige
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 13:42
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/30; H03H9/42; H03H9/44
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
91 words
A surface acoustic wave device comprising a substrate able to support surface acoustic waves, an input transducer for launching surface acoustic waves along a first track on the substrate, an output transducer for receiving surface acoustic waves from a second track on the substrate, and first and second reflective array structures arranged to reflect surface acoustic waves from the first track into the second track, the first and second reflective array structures each comprising numerous reflecting elements arranged parallel to one another in echalon across the first and second tracks respectively.
Claim 2
Dependent Claim
91 words
A surface acoustic wave device comprising a substrate able to support surface acoustic waves, an input transducer for launching surface acoustic waves along a first track on the substrate, an output transducer for receiving surface acoustic waves from a second track on the substrate, and first and second reflective array structures arranged to reflect surface acoustic waves from the first track into the second track, the first and second reflective array structures each comprising numerous reflecting elements arranged parallel to one another in echalon across the first and second tracks respectively.
Claim 3
Dependent Claim
16 words
A device as claimed in claim 1 wherein the spacing between the reflecting elements is periodic.
Claim 4
Dependent Claim
18 words
A device as claimed in claim 1 wherein the spacing between the reflecting elements varies along the arrays.
Claim 5
Dependent Claim
23 words
A device as claimed in claim 3 wherein the transducers have finger electrodes whose interspacing varies along the transducers to form dispersive transducers.
Claim 6
Dependent Claim
22 words
A device as claimed in claim 4 wherein the finger electrodes in each transducer are arranged in echalon across their respective tracks.
Claim 7
Dependent Claim
16 words
A device as claimed in claim 1 wherein the length of each reflecting element is equal.
Claim 8
Dependent Claim
21 words
A device as claimed in claim 1 wherein the length of each reflecting element varies along the length of the arrays.
Claim 9
Dependent Claim
17 words
A device as claimed in claim 1 wherein the transducers have finger electrodes which vary in length.
Claim 10
Dependent Claim
13 words
A device as claimed in claim 1 wherein the reflecting elements are strips.
Claim 11
Dependent Claim
13 words
A device as claimed in claim 1 wherein the reflecting elements are grooves.
Claim 12
Dependent Claim
17 words
A device as claimed in claim 1 wherein the length of the arrays lie along straight paths.
Claim 13
Dependent Claim
17 words
A device as claimed in claim 1 wherein the length of the arrays lie along curved paths.
Claim 14
Dependent Claim
12 words
A device as claimed in claim 1 wherein the substrate is quartz.
Claim 15
Dependent Claim
13 words
A device as claimed in claim 1 wherein the substrate is lithium niobate.
Claim 16
Dependent Claim
20 words
A device as claimed in claim 1 wherein the substrate is non-piezo electric and has piezelectric regions at the transducers.
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) | 1979-08-17 | 1980-02-16 | 1980-08-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-08-17 | 1984-02-16 | 1984-08-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-08-17 | 1988-02-16 | 1988-08-17 | $7700.00 | Window Closed / Lapsed |