US4401956A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronically variable time delay in piezoelectric media
Assignee: Individual
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Filing: 1981-09-14
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Granted: 1983-08-30
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Expires: 2001-09-14
Abstract
Abstract A variable delay line for surface acoustic waves includes spaced input and output transducers affixed on the wave-propagating surface of a piezoelectric substrate for sending and receiving acoustic waves. An AC or DC voltage is applied to the substrate through a pair of electrodes as a strain inducing signal. The applied voltage changes the time delay of the wave by physically altering the length of the propagation path, and/or by altering the effective properties of the substrate to vary the propagation velocity of the wave. The time delay will vary proportionately in response to the applied voltage.
Inventors
- 👤 Shrinivas G. Joshi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:15
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/30; H03H9/42; H03H9/423
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
129 words
A variable delay line for surface acoustic waves, comprising: a piezoelectric substrate having a wave-propagating surface; input and output transducer means affixed in spaced relation on said wave-propagating surface for sending and receiving surface acoustic waves on said surface; electrode means for connection to a source of variable voltage for producing a biasing electric field in said substrate to cause a strain in said substrate to vary the time delay of said waves, said time delay changeable proportionately in response to varying applied voltages, said electrode means includes a first electrode in the form of a grating positioned on said wave-propagating surface, a non-piezoelectric thin film deposited on said wave-propagating surface over said first electrode, and said electrode means further includes a second electrode positioned on said thin film.
Claim 2
Dependent Claim
129 words
A variable delay line for surface acoustic waves, comprising: a piezoelectric substrate having a wave-propagating surface; input and output transducer means affixed in spaced relation on said wave-propagating surface for sending and receiving surface acoustic waves on said surface; electrode means for connection to a source of variable voltage for producing a biasing electric field in said substrate to cause a strain in said substrate to vary the time delay of said waves, said time delay changeable proportionately in response to varying applied voltages, said electrode means includes a first electrode in the form of a grating positioned on said wave-propagating surface, a non-piezoelectric thin film deposited on said wave-propagating surface over said first electrode, and said electrode means further includes a second electrode positioned on said thin film.
Claim 3
Dependent Claim
132 words
A variable delay line for surface acoustic waves, comprising: a substrate element having a wave-propagating surface; input and output transducer means affixed in spaced relation on said wave-propagating surface for sending and receiving surface acoustic waves on said surface; electrode means for connection to a source of variable voltage for producing a biasing electric field in said substrate to cause a strain in said substrate to vary the time delay of said waves, said time delay changeable proportionately in response to varying applied voltages, said electrode means includes a first electrode positioned on said wave-propagating surface, a thin film element deposited on said wave-propagating surface over said first electrode, one of said elements composed of a piezoelectric material, and said electrode means further includes a second electrode positioned on said thin film.
Claim 4
Dependent Claim
132 words
A variable delay line for surface acoustic waves, comprising: a substrate element having a wave-propagating surface; input and output transducer means affixed in spaced relation on said wave-propagating surface for sending and receiving surface acoustic waves on said surface; electrode means for connection to a source of variable voltage for producing a biasing electric field in said substrate to cause a strain in said substrate to vary the time delay of said waves, said time delay changeable proportionately in response to varying applied voltages, said electrode means includes a first electrode positioned on said wave-propagating surface, a thin film element deposited on said wave-propagating surface over said first electrode, one of said elements composed of a piezoelectric material, and said electrode means further includes a second electrode positioned on said thin film.
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) | 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 |