US3883831A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Surface wave devices
Assignee: Massachusetts Institute of Technology
•
Filing: 1973-09-27
•
Granted: 1975-05-13
•
Expires: 1993-09-27
Abstract
Abstract A device for handling surface elastic waves using a plurality of reflective elements, such as grooves, on the surface thereof the dimensional characteristics of which may be arranged to vary in a predetermined manner from element to element to provide a bandpass filtering action on a surface wave reflected therefrom. The device may be formed in various configurations using single or double reflections to provide single or multiple filtering action or phase coded filter action and the orientation of the reflective elements may be varied to vary the center frequency of the filter. A further embodiment uses a compensating strip of material positioned in the propagating path of a surface wave, the dimensional characteristics of such strip being arranged to vary so as to change the velocity of the wave and to achieve phase error compensation thereby. Further, a strip of energy absorbing material may also be used to control the amplitude response of the filter.
Inventors
- 👤 Richard C Williamson
- 👤 Ernest Stern
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 09:11
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/46; H03H9/64; H03H9/6489; H03H9/02; H03H9/02535; H03H9/02637; H03H9/02685; H03H9/02771; H03H9/02795; H03H9/02803; H03H9/02811; H03H9/30; H03H9/42; H03H9/44
Claims Analysis
Total Claims: 51
Claim 1
Independent Claim
163 words
A device for handling surface elastic waves comprising a substrate capable of propagating surface elastic waves having a selected direction of propagation on a selected surface thereof; first transducer means formed on said surface for generating surface elastic waves on said surface in said direction; at least one set of parallel reflective elements having preselected dimensions being formed at said surface and arranged at a preselected angle of incidence to the direction of propagation of said surface elastic waves to provide a reflection of said surface elastic waves at a preselected angle of reflection; at least one of the dimensions of said reflective elements arranged to vary in a predetermined manner from element to element for achieving a non-linear relationship between the path length of said surface elastic wave and the frequency of said wave to provide a filtering action for said reflected surface elastic wave; and second transducer means formed on said surface for receiving said reflected and filtered surface elastic waves.
Claim 2
Independent Claim
163 words
A device for handling surface elastic waves comprising a substrate capable of propagating surface elastic waves having a selected direction of propagation on a selected surface thereof; first transducer means formed on said surface for generating surface elastic waves on said surface in said direction; at least one set of parallel reflective elements having preselected dimensions being formed at said surface and arranged at a preselected angle of incidence to the direction of propagation of said surface elastic waves to provide a reflection of said surface elastic waves at a preselected angle of reflection; at least one of the dimensions of said reflective elements arranged to vary in a predetermined manner from element to element for achieving a non-linear relationship between the path length of said surface elastic wave and the frequency of said wave to provide a filtering action for said reflected surface elastic wave; and second transducer means formed on said surface for receiving said reflected and filtered surface elastic waves.
Claim 3
Dependent Claim
29 words
A device in accordance with claim 1 wherein said reflective elements are grooves and the lengths of said grooves are varied in a predetermined manner from groove to groove.
Claim 4
Dependent Claim
29 words
A device in accordance with claim 1 wherein said reflective elements are grooves and the depths of said grooves are varied in a predetermined manner from groove to groove.
Claim 5
Dependent Claim
85 words
A device in accordance with claim 1 wherein a plurality of sets of said parallel reflective elements are formed in said surface, one of the dimensions of said reflective elements in each set thereof being varied in a predetermined manner from element to element to produce a plurality of reflected and filtered surface elastic waves; and said second transducer means comprises a plurality of receiver transducer means, each formed on said surface to separately receive one of said plurality of reflected and filtered surface waves.
Claim 6
Dependent Claim
29 words
A device in accordance with claim 4 wherein said reflective elements are grooves and the lengths of said grooves are varied in a predetermined manner from groove to groove.
Claim 7
Dependent Claim
29 words
A device in accordance with claim 4 wherein said reflective elements are grooves and the depths of said grooves are varied in a predetermined manner from groove to groove.
Claim 8
Independent Claim
174 words
A device for handling surface elastic waves comprising a substrate capable of propagating surface elastic waves on a surface thereof; first transducer means formed on said surface for generating surface elastic waves on said surface; a first set of parallel reflective elements having uniform spacing therebetween and preselected dimensions formed at said surface and arranged at a preselected angle of incidence to the direction of propagation of said surface elastic waves to provide a first reflection of said surface elastic waves at a first preselected angle of reflection; a second set of parallel reflective elements having uniform spacing therebetween and preselected dimensions formed in said surface adjacent said first set of grooves and arranged at a preselected angle of incidence to the direction of propagation of said surface elastic waves reflected from said first set of parallel reflective elements to provide a second reflection of said first reflected surface elastic waves at a second preselected angle of reflection; and second transducer means formed on said surface for receiving said second reflected surface elastic waves.
Claim 9
Independent Claim
174 words
A device for handling surface elastic waves comprising a substrate capable of propagating surface elastic waves on a surface thereof; first transducer means formed on said surface for generating surface elastic waves on said surface; a first set of parallel reflective elements having uniform spacing therebetween and preselected dimensions formed at said surface and arranged at a preselected angle of incidence to the direction of propagation of said surface elastic waves to provide a first reflection of said surface elastic waves at a first preselected angle of reflection; a second set of parallel reflective elements having uniform spacing therebetween and preselected dimensions formed in said surface adjacent said first set of grooves and arranged at a preselected angle of incidence to the direction of propagation of said surface elastic waves reflected from said first set of parallel reflective elements to provide a second reflection of said first reflected surface elastic waves at a second preselected angle of reflection; and second transducer means formed on said surface for receiving said second reflected surface elastic waves.
Claim 10
Dependent Claim
40 words
A device in accordance with claim 7 wherein said reflective elements are grooves and at least one of said dimensions of the grooves in at least one of said sets are varied in a predetermined manner from groove to groove.
Claim 11
Dependent Claim
36 words
A device in accordance with claim 8 wherein said reflective elements are grooves and the depths of the grooves in at least one of said sets are varied in a predetermined manner from grooves to groove.
Claim 12
Dependent Claim
30 words
A device in accordance with claim 8 wherein the lengths of the grooves in at least one of said sets are varied in a predetermined manner from groove to groove.
Claim 13
Dependent Claim
43 words
A device in accordance with claim 7 wherein said reflective elements are grooves and the grooves of said second set of grooves are parallel to the grooves of said first set of grooves whereby the second reflection is in said direction of propagation.
Claim 14
Dependent Claim
36 words
A device in accordance with claim 7 wherein said second set of grooves is a mirror-image of said first set of grooves whereby the second reflection is in a direction opposite to said direction of propagation.
Claim 15
Independent Claim
258 words
A device for handling surface elastic waves comprising a substrate capable of propagating surface elastic waves on a surface thereof; first transducer means formed on said surface for generating surface elastic waves having a selected direction of propagation on said surface; a plurality of first sets of parallel reflective elements formed at said surface, the elements in each of said first sets having preselected dimensions and arranged at a preselected angle of incidence to the direction of propagation of said surface elastic waves to provide a first reflection of said surface elastic waves at a first preselected angle of reflection; at least one of said dimensions of at least one of said plurality of first sets of reflective elements being arranged to vary in a predetermined manner from element to element to provide a filtering action for said first reflected surface elastic wave; a plurality of second sets of parallel reflective elements the elements in each of said second sets having preselected dimensions and being formed at said surface, each set being formed adjacent one of said first sets of reflective elements and arranged at a preselected angle of incidence to the direction of propagation of the surface elastic waves reflected from said adjacent one of said first set of reflective elements to provide a second reflection of said surface elastic waves at a second preselected angle of reflection; and a plurality of receiving transducer means each receiving one of said second reflected surface elastic waves from one of said plurality of second sets of parallel reflective elements.
Claim 16
Independent Claim
258 words
A device for handling surface elastic waves comprising a substrate capable of propagating surface elastic waves on a surface thereof; first transducer means formed on said surface for generating surface elastic waves having a selected direction of propagation on said surface; a plurality of first sets of parallel reflective elements formed at said surface, the elements in each of said first sets having preselected dimensions and arranged at a preselected angle of incidence to the direction of propagation of said surface elastic waves to provide a first reflection of said surface elastic waves at a first preselected angle of reflection; at least one of said dimensions of at least one of said plurality of first sets of reflective elements being arranged to vary in a predetermined manner from element to element to provide a filtering action for said first reflected surface elastic wave; a plurality of second sets of parallel reflective elements the elements in each of said second sets having preselected dimensions and being formed at said surface, each set being formed adjacent one of said first sets of reflective elements and arranged at a preselected angle of incidence to the direction of propagation of the surface elastic waves reflected from said adjacent one of said first set of reflective elements to provide a second reflection of said surface elastic waves at a second preselected angle of reflection; and a plurality of receiving transducer means each receiving one of said second reflected surface elastic waves from one of said plurality of second sets of parallel reflective elements.
Claim 17
Dependent Claim
52 words
A device in accordance with claim 13 wherein at least one of said dimensions of at least one of said plurality of second sets of parallel reflective elements is arranged to vary in a predetermined manner from element to element to provide a filtering action for said second reflected surface elastic waves.
Claim 18
Dependent Claim
31 words
A device in accordance with claim 13 wherein said reflective elements are grooves and the lengths of at least one of said plurality of first sets of parallel grooves are varied.
Claim 19
Dependent Claim
31 words
A device in accordance with claim 13 wherein said reflective elements are grooves and the depths of at least one of said plurality of first sets of parallel grooves are varied.
Claim 20
Dependent Claim
31 words
A device in accordance with claim 14 wherein said reflective elements are grooves and the lengths of at least one of said plurality of second sets of parallel grooves are varied.
Claim 21
Dependent Claim
31 words
A device in accordance with claim 14 wherein said reflective elements are grooves and the depths of at least one of said plurality of second sets of parallel grooves are varied.
Claim 22
Independent Claim
219 words
A device for handling surface elastic waves comprising a substrate capable of propagating surface elastic waves on a surface thereof; first transducer means formed on said surface for generating surface elastic waves on said surface; a first set of parallel reflective elements having substantially uniform dimensions formed at said surface and arranged at a preselected angle of incidence to the direction of propagation of said surface elastic waves to provide a first reflection of said surface elastic waves at a first preselected angle of reflection, the spacing between said Reflective elements varying in a predetermined manner; a second set of parallel reflective elements having substantially uniform dimensions formed in said surface adjacent said first set of reflective elements and arranged so that all of the reflective elements of said second set are parallel to the reflective elements of said first set so as to present a preselected angle of incidence to the surface elastic waves reflected from said first set to provide a second reflection of said first reflected surface elastic waves at a second preselected angle of reflection, the spacing between the reflective elements of said second set varying in substantially the same predetermined manner as the spacing of said first set; and second transducer means formed on said surface for receiving said second reflected surface elastic waves.
Claim 23
Independent Claim
219 words
A device for handling surface elastic waves comprising a substrate capable of propagating surface elastic waves on a surface thereof; first transducer means formed on said surface for generating surface elastic waves on said surface; a first set of parallel reflective elements having substantially uniform dimensions formed at said surface and arranged at a preselected angle of incidence to the direction of propagation of said surface elastic waves to provide a first reflection of said surface elastic waves at a first preselected angle of reflection, the spacing between said Reflective elements varying in a predetermined manner; a second set of parallel reflective elements having substantially uniform dimensions formed in said surface adjacent said first set of reflective elements and arranged so that all of the reflective elements of said second set are parallel to the reflective elements of said first set so as to present a preselected angle of incidence to the surface elastic waves reflected from said first set to provide a second reflection of said first reflected surface elastic waves at a second preselected angle of reflection, the spacing between the reflective elements of said second set varying in substantially the same predetermined manner as the spacing of said first set; and second transducer means formed on said surface for receiving said second reflected surface elastic waves.
Claim 24
Dependent Claim
46 words
A device in accordance with claim 19 wherein said reflective elements are grooves and the spacing between the grooves in each of said first and second sets varies in accordance with the distance of said grooves from said first transducer means along said direction of propagation.
Claim 25
Independent Claim
203 words
A device for handling surface elastic waves to provide a phase-coded filtering action over a specified bandwidth comprising a substrate capable of propagating surface elastic waves having a preselected direction of propagation on a surface thereof; input transducer means formed on said surface for generating surface elastic waves on said surface in said direction; a set of parallel reflective elements formed in said surface and arranged at a preselected angle of incidence to said direction of propagation, said set comprising a plurality of separate groups of said reflective elements, the spacing between the reflective elements in each group being uniform and the number of reflective elements within each said group being selected to provide a response over said specified bandwidth, and the spacing between each group having one of a plurality of selected values, for producing a plurality of reflected surface elastic waves, each at a preselected angle of reflection, each of said values selected to introduce a predetermined phase-shaft for said reflected surface elastic waves; and output transducer means formed on said surface and responsive to said plurality of reflected surface elastic waves for producing a plurality of electrical signals and for adding said electrical signals to provide a matched filter operation.
Claim 26
Independent Claim
203 words
A device for handling surface elastic waves to provide a phase-coded filtering action over a specified bandwidth comprising a substrate capable of propagating surface elastic waves having a preselected direction of propagation on a surface thereof; input transducer means formed on said surface for generating surface elastic waves on said surface in said direction; a set of parallel reflective elements formed in said surface and arranged at a preselected angle of incidence to said direction of propagation, said set comprising a plurality of separate groups of said reflective elements, the spacing between the reflective elements in each group being uniform and the number of reflective elements within each said group being selected to provide a response over said specified bandwidth, and the spacing between each group having one of a plurality of selected values, for producing a plurality of reflected surface elastic waves, each at a preselected angle of reflection, each of said values selected to introduce a predetermined phase-shaft for said reflected surface elastic waves; and output transducer means formed on said surface and responsive to said plurality of reflected surface elastic waves for producing a plurality of electrical signals and for adding said electrical signals to provide a matched filter operation.
Claim 27
Dependent Claim
13 words
A device in accordance with claim 21 wherein said reflective elements are grooves.
Claim 28
Dependent Claim
26 words
A device in accordance with claim 21 wherein the spacing between each group has one of more than two selected values for providing multiphase coded operation.
Claim 29
Dependent Claim
56 words
A device in accordance with claim 21 wherein said uniform spacing between the elements in each group is approximately equal to one wavelength of said surface elastic wave and the spacing between each group is one of two selected values which are approximately equal to one-half wavelength and one wavelength, respectively, of said surface elastic wave.
Claim 30
Independent Claim
165 words
A device for handling surface elastic waves comprising a substrate capable of propagating surface elastic waves having a preselected direction of propagation on a surface thereof; first transducer means formed on said surface for generating surface elastic waves on said surface in said direction; at least one plurality of parallel reflective elements formed at said surface and arranged at a preselected angle of incidence to said direction to provide a reflection of said surface elastic wave at a preselected angle of reflection; second transducer means for receiving said reflected surface elastic wave; and a layer of preselected material deposited on said surface in the path of said reflected wave, a dimension of said layer arranged so as to vary from one end to the other of said plurality of reflective elements to vary the velocity of the reflective wave from said one end to the other to adjust the phases of the reflected components of said surface elastic wave received at said second transducer means.
Claim 31
Independent Claim
165 words
A device for handling surface elastic waves comprising a substrate capable of propagating surface elastic waves having a preselected direction of propagation on a surface thereof; first transducer means formed on said surface for generating surface elastic waves on said surface in said direction; at least one plurality of parallel reflective elements formed at said surface and arranged at a preselected angle of incidence to said direction to provide a reflection of said surface elastic wave at a preselected angle of reflection; second transducer means for receiving said reflected surface elastic wave; and a layer of preselected material deposited on said surface in the path of said reflected wave, a dimension of said layer arranged so as to vary from one end to the other of said plurality of reflective elements to vary the velocity of the reflective wave from said one end to the other to adjust the phases of the reflected components of said surface elastic wave received at said second transducer means.
Claim 32
Dependent Claim
19 words
A device in accordance with claim 25 wherein said layer is conductive and said dimension is the width thereof.
Claim 33
Dependent Claim
16 words
A device in accordance with claim 26 wherein said layer is at least 200 A thick.
Claim 34
Dependent Claim
28 words
A device in accordance with claim 27 wherein the thickness of said layer is not greater than that thickness which would introduce excessive mass loading of said substrate.
Claim 35
Dependent Claim
19 words
A device in accordance with claim 25 wherein said layer is non-conductive and said dimension is the width thereof.
Claim 36
Dependent Claim
19 words
A device in accordance with claim 25 wherein said layer is non-conductive and said dimension is the thickness thereof.
Claim 37
Independent Claim
232 words
A device for handling surface elastic waves comprising a substrate capable of propagating surface elastic waves having a preselected direction of propagation on a surface thereof; first transducer means formed on said surface for generating surface elastic waves on said surface in said direction; a first plurality of parallel reflective elements formed in said surface and arranged at a preselected angle of incidence to said direction of propagation to provide a first reflection of said surface elastic waves at a first preselected angle of reflection; a second plurality of parallel reflective elements adjacent said first plurality of parallel reflective elements formed at said surface to provide a second reflection of said first reflected surface elastic waves at a second preselected angle of reflection; second transducer means for receiving said second reflected surface elastic waves from said second plurality of reflective elements; and a layer of preselected material deposited on said surface along the region between said first and said second plurality of parallel reflective elements, a dimension of said layer being arranged to vary so as to change the velocity of the surface elastic wave reflected from said first plurality of reflective elements through said layer to said second plurality of reflective elements substantially from one end to the other of said first plurality of reflective elements to adjust the phase of said surface elastic waves received at said second transducer means.
Claim 38
Independent Claim
232 words
A device for handling surface elastic waves comprising a substrate capable of propagating surface elastic waves having a preselected direction of propagation on a surface thereof; first transducer means formed on said surface for generating surface elastic waves on said surface in said direction; a first plurality of parallel reflective elements formed in said surface and arranged at a preselected angle of incidence to said direction of propagation to provide a first reflection of said surface elastic waves at a first preselected angle of reflection; a second plurality of parallel reflective elements adjacent said first plurality of parallel reflective elements formed at said surface to provide a second reflection of said first reflected surface elastic waves at a second preselected angle of reflection; second transducer means for receiving said second reflected surface elastic waves from said second plurality of reflective elements; and a layer of preselected material deposited on said surface along the region between said first and said second plurality of parallel reflective elements, a dimension of said layer being arranged to vary so as to change the velocity of the surface elastic wave reflected from said first plurality of reflective elements through said layer to said second plurality of reflective elements substantially from one end to the other of said first plurality of reflective elements to adjust the phase of said surface elastic waves received at said second transducer means.
Claim 39
Dependent Claim
19 words
A device in accordance with claim 31 wherein said layer is conductive and said dimension is the width thereof.
Claim 40
Dependent Claim
19 words
A device in accordance with claim 31 wherein said layer is non-conductive and said dimension is the width thereof.
Claim 41
Dependent Claim
19 words
A device in accordance with claim 31 wherein said layer is non-conductive and said dimension is the thickness thereof.
Claim 42
Dependent Claim
47 words
A device in accordance with claim 1 wherein the lengths of at least some of said reflective elements are progressively increased in the direction of propagation to compensate for energy losses incurred by said surface elastic wave as it is propagated along said set of reflective elements.
Claim 43
Dependent Claim
68 words
A device in accordance with claim 1 where the spacing between selected adjacent ones of said reflective elements are approximately equal to one-half the wavelength of the surface elastic wave propagated along said reflective elements to provide phase reversals at selected regions of reflection along said set, the spacing between adjacent ones of the remaining said elements being approximately equal to one wavelenth of said surface elastic wave.
Claim 44
Independent Claim
157 words
A device for handling surface elastic waves comprising a substrate capable of propagating surface elastic waves having a preselected direction of propagation on a surface thereof; first transducer means formed on said surface for generating surface elastic waves on said surface in said direction; at least one plurality of parallel reflective elements formed at said surface and arranged at a preselected angle of incidence to said direction to provide a reflection of said surface elastic wave at a preselected angle of reflection; second transducer means for receiving said reflected surface elastic wave; and a layer of preselected energy absorbing material deposited on said surface in the path of said reflected wave, a dimension of said layer arranged so as to vary from one end to the other of said reflective elements to vary the amplitude from said one end to the other of the reflected components of said surface elastic wave received at said second transducer means.
Claim 45
Independent Claim
157 words
A device for handling surface elastic waves comprising a substrate capable of propagating surface elastic waves having a preselected direction of propagation on a surface thereof; first transducer means formed on said surface for generating surface elastic waves on said surface in said direction; at least one plurality of parallel reflective elements formed at said surface and arranged at a preselected angle of incidence to said direction to provide a reflection of said surface elastic wave at a preselected angle of reflection; second transducer means for receiving said reflected surface elastic wave; and a layer of preselected energy absorbing material deposited on said surface in the path of said reflected wave, a dimension of said layer arranged so as to vary from one end to the other of said reflective elements to vary the amplitude from said one end to the other of the reflected components of said surface elastic wave received at said second transducer means.
Claim 46
Dependent Claim
35 words
A device in accordance with claim 1 wherein said preselected angles of incidence and reflection are arranged to provide a right angle reflection of said surface elastic waves at said set of parallel reflective elements.
Claim 47
Dependent Claim
40 words
A device in accordance with claim 1 wherein said preselected angles of incidence and reflection are arranged to provide a reflection of said surface elastic waves at said set of parallel reflective elements which is other than a right angle.
Claim 48
Dependent Claim
66 words
A device in accordance with claim 4 wherein the dimensions of each set of said reflective elements are varied in the same predetermined manner and the preselected angles of incidence and reflection are different for each said set so that surface elastic waves are reflected at different angles at each said set, the center frequency of the filtered waves at each said set thereby being different.
Claim 49
Dependent Claim
55 words
A device in accordance with claim 1 wherein a single set of said parallel reflective elements is formed at said surface and said preselected angles of incidence and reflection are arranged to provide a reflection of said surface elastic waves at said single set of parallel reflective elements which is other than a 180* reflection.
Claim 50
Dependent Claim
36 words
A device in accordance with claim 41 wherein said preselected angles of incidence and reflection are arranged to provide a right angle reflection of said surface elastic waves at said single set of parallel reflective elements.
Claim 51
Dependent Claim
35 words
A device in accordance with claim 1 wherein said reflective elements are arranged so that the path length of said surface elastic wave is substantially constant independently of frequency to provide a bandpass filtering action.
References Cited (Backward Citations)
US3568102A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-12 | 1978-11-11 | 1979-05-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-12 | 1982-11-11 | 1983-05-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-12 | 1986-11-11 | 1987-05-13 | $7700.00 | Window Closed / Lapsed |