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US4760360A
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Surface-wave resonator structure having metallization strips interrupted in sub-sections in reflector fingers
Assignee: Siemens AG
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Filing: 1987-08-11
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Granted: 1988-07-26
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Expires: 2007-08-11
Abstract
Abstract A surface-wave resonator filter having at least two reflector structures and at least one interdigital transducer. At least a portion of one of the reflector structures has interruptions in the metallization strips thereof to define subsections of the metallization strip. Connecting metallizations are provided parallel to the wave propagation direction x between neighboring sub-sections of neighboring sub-divided metallization strips to electrically connect the neighboring sub-sections such that no two sub-sections of the same sub-divided metallization strip are electrically connected.
Inventors
- 👤 Hans P. Grassl
- 👤 Peter Zibis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 08:45
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/02; H03H9/02535; H03H9/02818; H03H9/02842; H03H9/02637; H03H9/02685; H03H9/02771
Claims Analysis
Total Claims: 53
Claim 1
Independent Claim
306 words
A surface-wave resonator filter comprising: at least two reflector structures composed of metallization strips on a substrate of piezoelectric material; at least one interdigital transducer on said substrate of piezoelectric material in which a wave propagation in a direction x perpendicular to said metallization strips exists, said metallization strips having multiple interruptions in a transverse direction y relative to said wave propagation x, whereby for at least one of said reflector structures for at least a portion thereof, at least a plurality of said metallization strips are provided with said interruptions distributed relative to one another in said direction y of said metallization strips, thereby dividing these metallization strips into sub-sections; said reflector structure having the same plurality of interruptions of said metallization strips at least in a region of a portion of said reflector structure in a direction of said wave propagation direction x; said portion divided into a plurality of zones parallel to said wave propagation direction x which is equal in number to the plurality of interruptions and respectively only one interruption of a respectively sub-divided metallization strip present in the region of each and every one of these zones, said interruptions arranged distributed relative to one another within a respective zone; connecting metallization proceeding in the direction of the wave propagation direction x provided between neighboring sub-sections of neighboring metallization strips, a respective sub-section of a metallization strip being electrically connected to a respectively neighboring sub-section of a neighboring metallization strip with these connecting metallizations, at least one sub-section other than end residing sub-sections of a metallization strip being electrically connected to a respectively neighboring sub-section other than end residing sub-sections of a neighboring metaiiization strip with one of said connecting metallizations, whereby no connecting metallizations are present which provide electrical connection between two sub-sections of one and the same metallization strip.
Claim 2
Dependent Claim
306 words
A surface-wave resonator filter comprising: at least two reflector structures composed of metallization strips on a substrate of piezoelectric material; at least one interdigital transducer on said substrate of piezoelectric material in which a wave propagation in a direction x perpendicular to said metallization strips exists, said metallization strips having multiple interruptions in a transverse direction y relative to said wave propagation x, whereby for at least one of said reflector structures for at least a portion thereof, at least a plurality of said metallization strips are provided with said interruptions distributed relative to one another in said direction y of said metallization strips, thereby dividing these metallization strips into sub-sections; said reflector structure having the same plurality of interruptions of said metallization strips at least in a region of a portion of said reflector structure in a direction of said wave propagation direction x; said portion divided into a plurality of zones parallel to said wave propagation direction x which is equal in number to the plurality of interruptions and respectively only one interruption of a respectively sub-divided metallization strip present in the region of each and every one of these zones, said interruptions arranged distributed relative to one another within a respective zone; connecting metallization proceeding in the direction of the wave propagation direction x provided between neighboring sub-sections of neighboring metallization strips, a respective sub-section of a metallization strip being electrically connected to a respectively neighboring sub-section of a neighboring metallization strip with these connecting metallizations, at least one sub-section other than end residing sub-sections of a metallization strip being electrically connected to a respectively neighboring sub-section other than end residing sub-sections of a neighboring metaiiization strip with one of said connecting metallizations, whereby no connecting metallizations are present which provide electrical connection between two sub-sections of one and the same metallization strip.
Claim 3
Dependent Claim
43 words
The surface-wave resonator filter described in claim 1, wherein said reflector structure comprises a plurality of portions having interruptions of said metallization strips and having connecting metallizations between said sub-sections thereof, said portions comprising mutually differing pluralities of interruptions of said metallization strips.
Claim 4
Dependent Claim
18 words
The surface-wave resonator filter described in claim 1, wherein said reflector structure also has a portion without interruptions.
Claim 5
Dependent Claim
21 words
The surface-wave resonator filter described in claim 1, wherein the number of interruptions is in the range of 2 to 5.
Claim 6
Dependent Claim
24 words
The surface-wave resonator filter described in claim 1, wherein the interruptions within a zone of the reflector structure are arranged in a random distribution.
Claim 7
Dependent Claim
21 words
The surface-wave resonator filter described in claim 1, wherein the connecting metallizations of respectively end-residing sub-sections are fashioned as bus bars.
Claim 8
Dependent Claim
28 words
The surface-wave resonator filter described in claim 1, wherein the interruptions of the metallization strips are dimensioned roughly of the size of the width of the metallization strips.
Claim 9
Dependent Claim
36 words
The surface-wave resonator filter described in claim 1, wherein the connecting metallizations are dimensioned with a width (transversely relative to the wave propagation direction (x)) of about the size of the width of the metallization strips.
Claim 10
Dependent Claim
41 words
The surface-wave resonator described in claim 1, wherein each sub-section other then end residing sub-sections of a metallization strip are electrically connected to a respectively neighboring sub-section other than end residing sub-sections of a neighboring metallization strip with said connecting metallizations.
Claim 11
Dependent Claim
280 words
A surface-wave resonator filter comprising: piezoelectric substrate; at least two reflector structures having metallization strips on said substrate; at least one interdigital transducer on said substrate and adjacent said reflector structures in which a wave propagation in a direction x perpendicular to said metallization strip exists; said metallization strips of at least one of said reflector structures having multiple interruptions in a transverse direction y relative to said wave propagation direction x; at least a portion of said one of said reflector structures having said interruptions distributed relative to one another in said direction y of said metallization strips to define sub-sections of said metallization strips thereby defining a sub-divided metallization strip; said one of said reflector structures having the same plurality of interruptions for each of said metallization strips at least in a region of said portion of said one of said reflector structures in said wave propagation direction x; said portion divided into a plurality of zones parallel to said wave propagation direction x which is equal in number to said plurality of interruptions, only one interruption of said sub-divided metallization strip present in each of said zones, said interruptions within a respective zone arranged in a distribution relative to one another; and connecting metallizations parallel to said wave propagation direction x provided between neighboring sub-sections of neighboring sub-divided metallization strips to electrically connect said neighboring sub-sections such that no two sub-sections of the same sub-divided metallization strip are electrically connected, at least one sub-section other than end residing sub-sections of a metallization strip being electrically connected to a respectively neighboring sub-section other than end residing sub-sections of a neighboring metallization strip with one of said connecting metallizations.
Claim 12
Dependent Claim
280 words
A surface-wave resonator filter comprising: piezoelectric substrate; at least two reflector structures having metallization strips on said substrate; at least one interdigital transducer on said substrate and adjacent said reflector structures in which a wave propagation in a direction x perpendicular to said metallization strip exists; said metallization strips of at least one of said reflector structures having multiple interruptions in a transverse direction y relative to said wave propagation direction x; at least a portion of said one of said reflector structures having said interruptions distributed relative to one another in said direction y of said metallization strips to define sub-sections of said metallization strips thereby defining a sub-divided metallization strip; said one of said reflector structures having the same plurality of interruptions for each of said metallization strips at least in a region of said portion of said one of said reflector structures in said wave propagation direction x; said portion divided into a plurality of zones parallel to said wave propagation direction x which is equal in number to said plurality of interruptions, only one interruption of said sub-divided metallization strip present in each of said zones, said interruptions within a respective zone arranged in a distribution relative to one another; and connecting metallizations parallel to said wave propagation direction x provided between neighboring sub-sections of neighboring sub-divided metallization strips to electrically connect said neighboring sub-sections such that no two sub-sections of the same sub-divided metallization strip are electrically connected, at least one sub-section other than end residing sub-sections of a metallization strip being electrically connected to a respectively neighboring sub-section other than end residing sub-sections of a neighboring metallization strip with one of said connecting metallizations.
Claim 13
Dependent Claim
51 words
The surface-wave resonator filter described in claim 10, wherein said reflector structure comprises a plurality of portions having interruptions of said sub-divided metallization strips with connecting metallizations between sub-sections of said sub-divided metallization strips, at least some of said portions comprising mutually differing pluralities of interruptions in said sub-divided metallization strips.
Claim 14
Dependent Claim
20 words
The surface-wave resonator described in claim 10, wherein said reflector structure has a portion without interruption in metallization strips thereof.
Claim 15
Dependent Claim
21 words
The surface-wave resonator described in claim 10, wherein the number of interruptions in said sub-divided metallization strip is at least 2.
Claim 16
Dependent Claim
22 words
The surface-wave resonator described in claim 10, wherein the number of interruptions in said sub-divided metallization strip is not greater than 5.
Claim 17
Dependent Claim
18 words
The surface-wave resonator described in claim 10, wherein said distribution of said interruptions within a zone is random.
Claim 18
Dependent Claim
24 words
The surface-wave resonator described in claim 10, wherein said connecting metallization of end-residing sub-sections of said sub-divided metallization strips are fashioned as bus bars.
Claim 19
Dependent Claim
25 words
The surface-wave resonator described in claim 10, wherein the width of said connecting metallizations is substantially equal to the width of said sub-divided metallization strips.
Claim 20
Dependent Claim
25 words
The surface-wave resonator described in claim 10, wherein the length of said connecting metallizations is substantially equal to the width of said sub-divided metallization strips.
Claim 21
Dependent Claim
41 words
The surface-wave resonator described in claim 10, wherein each sub-section other than end residing sub-sections of a metallization strip are electricaily connected to a respectively neighboring sub-section other than end residing sub-sections of a neighboring metallization strip with said connecting metallizations.
Claim 22
Dependent Claim
295 words
A surface-wave resonator filter comprising: at least two reflector structures composed of metallization strips on a substrate of piezoelectric material; at least one interdigital transducer on said substrate of piezoelectric material in which a wave propagation in a direction x perpendicular to said metaliization strips exists, said metallization strips having multiple interruptions in a transverse direction y relative to said wave propagation x, whereby for at least one of said reflector structures for at least a portion thereof, at least a plurality of said metallization strips are provided with said interruptions distributed relative to one another in said direction y of said metaliization strips thereby dividing these metallization strips into sub-sections; said reflector structure having the same plurality of interruptions of said metallization strips at least in a region of a portion of said reflector structure in a direction of said wave propagation direction x; said portion divided into a plurality of zones parallel to said wave propagation direction x which is equal in number to the plurality of interruptions and respectively only one interruption of a respectively sub-divided metallization strip present in the region of each and every one of these zones, said interruptions arranged distributed relative to one another within a respective zone; connecting metallization proceeding in the direction of sub-sections of neighboring metallization strips, a respective sub-section of a metallization strip being electrically connected to a respectively neighboring sub-section of a neighboring metallization strip with these connecting metallizations, whereby no connecting metallizations are present which provide electrical connection between two sub-sections of one and the same metallization strip; said reflector structure further having a plurality of portions having interruptions of said metallization strips and having connecting metallizations between said sub-sections thereof, said portions having mutually differing pluralities of interruptions of metallization strips.
Claim 23
Dependent Claim
295 words
A surface-wave resonator filter comprising: at least two reflector structures composed of metallization strips on a substrate of piezoelectric material; at least one interdigital transducer on said substrate of piezoelectric material in which a wave propagation in a direction x perpendicular to said metaliization strips exists, said metallization strips having multiple interruptions in a transverse direction y relative to said wave propagation x, whereby for at least one of said reflector structures for at least a portion thereof, at least a plurality of said metallization strips are provided with said interruptions distributed relative to one another in said direction y of said metaliization strips thereby dividing these metallization strips into sub-sections; said reflector structure having the same plurality of interruptions of said metallization strips at least in a region of a portion of said reflector structure in a direction of said wave propagation direction x; said portion divided into a plurality of zones parallel to said wave propagation direction x which is equal in number to the plurality of interruptions and respectively only one interruption of a respectively sub-divided metallization strip present in the region of each and every one of these zones, said interruptions arranged distributed relative to one another within a respective zone; connecting metallization proceeding in the direction of sub-sections of neighboring metallization strips, a respective sub-section of a metallization strip being electrically connected to a respectively neighboring sub-section of a neighboring metallization strip with these connecting metallizations, whereby no connecting metallizations are present which provide electrical connection between two sub-sections of one and the same metallization strip; said reflector structure further having a plurality of portions having interruptions of said metallization strips and having connecting metallizations between said sub-sections thereof, said portions having mutually differing pluralities of interruptions of metallization strips.
Claim 24
Dependent Claim
18 words
The surface-wave resonator filter described in claim 20, wherein said reflector structure also has a portion without interruptions.
Claim 25
Dependent Claim
21 words
The surface-wave resonator filter described in claim 20, wherein the number of interruptions is in the range of 2 to 5.
Claim 26
Dependent Claim
24 words
The surface-wave resonator filter described in claim 20, wherein the interruptions within a zone of the reflector structure are arranged in a random distribution.
Claim 27
Dependent Claim
21 words
The surface-wave resonator filter described in claim 20, wherein the connecting metallizations of respectively end-residing sub-sections are fashioned as bus bars.
Claim 28
Dependent Claim
28 words
The surface-wave resonator filter described in claim 20, wherein the interruptions of the metallization strips are dimensioned roughly of the size of the width of the metallization strips.
Claim 29
Dependent Claim
36 words
The surface-wave resonator filter described in claim 20, wherein the connecting metallizations are dimensioned with a width (transversely relative to the wave propagation direction (x)) of about the size of the width of the metallization strips.
Claim 30
Dependent Claim
289 words
A surface-wave resonator filter comprising: piezoelectric substrate; at least two reflector structures having metallization strips on said substrate; at least one interdigital transducer on said substrate and adjacent said reflector structures in which a wave propagation in a direction x perpendicular to said metallization strip exists; said metallization strips of at least one of said reflector structures having multiple interruptions in a transverse direction y relative to said wave propagation direction x; at least a portion of said one of said reflector structures having said interruptions distributed relative to one another in said direction y of said metallization strips to define sub-sections of said metallization strips thereby defining a sub-divided metallization strip; said one of reflector structures having the same plurality of interruptions for each of said metallization strips at least in a region of said portion of said one of said reflector structures in said wave propagation direction x; said portion divided into a plurality of zones parallel to said wave propagation direction x which is equal in number to said plurality of interruptions, only one interruption of said sub-divided metallization strip present in each of said zones, said interruptions within a respective zone arranged in a distribution relative to one another; and connecting metallizations parallel to said wave propagation direction x provided between neighboring sub-section of neighboring sub-divided metallization strips to electrically connect said neighboring sub-section such that no two sub-sections of the same sub-divided metallization strip are electrically connected; said one of said reflector structure further having a plurality of portions having interruptions of said sub-divided metallization strips with connecting metallization between sub-sections sections of said sub-divided metallization strips, at least some of said portions having mutually differing pluralities of interruptions in said sub-divided metallization strips.
Claim 31
Dependent Claim
289 words
A surface-wave resonator filter comprising: piezoelectric substrate; at least two reflector structures having metallization strips on said substrate; at least one interdigital transducer on said substrate and adjacent said reflector structures in which a wave propagation in a direction x perpendicular to said metallization strip exists; said metallization strips of at least one of said reflector structures having multiple interruptions in a transverse direction y relative to said wave propagation direction x; at least a portion of said one of said reflector structures having said interruptions distributed relative to one another in said direction y of said metallization strips to define sub-sections of said metallization strips thereby defining a sub-divided metallization strip; said one of reflector structures having the same plurality of interruptions for each of said metallization strips at least in a region of said portion of said one of said reflector structures in said wave propagation direction x; said portion divided into a plurality of zones parallel to said wave propagation direction x which is equal in number to said plurality of interruptions, only one interruption of said sub-divided metallization strip present in each of said zones, said interruptions within a respective zone arranged in a distribution relative to one another; and connecting metallizations parallel to said wave propagation direction x provided between neighboring sub-section of neighboring sub-divided metallization strips to electrically connect said neighboring sub-section such that no two sub-sections of the same sub-divided metallization strip are electrically connected; said one of said reflector structure further having a plurality of portions having interruptions of said sub-divided metallization strips with connecting metallization between sub-sections sections of said sub-divided metallization strips, at least some of said portions having mutually differing pluralities of interruptions in said sub-divided metallization strips.
Claim 32
Dependent Claim
20 words
The surface-wave resonator described in claim 27, wherein said reflector structure has a portion without interruption in metallization strips thereof.
Claim 33
Dependent Claim
21 words
The surface-wave resonator described in claim 27, wherein the number of interruptions in said sub-divided metallization strip is at least 2.
Claim 34
Dependent Claim
22 words
The surface-wave resonator described in claim 27, wherein the number of interruptions in said sub-divided metallization strip is not greater than 5.
Claim 35
Dependent Claim
18 words
The surface-wave resonator described in claim 27, wherein said distribution of said interruptions within a zone is random.
Claim 36
Dependent Claim
24 words
The surface-wave resonator described in claim 27, wherein said connecting metallization of end-residing sub-sections of said sub-divided metallization strips are fashioned as bus bars.
Claim 37
Dependent Claim
25 words
The surface-wave resonator described in claim 27, wherein the width of said connecting metallizations is substantially equal to the width of said sub-divided metallization strips.
Claim 38
Dependent Claim
25 words
The surface-wave resonator described in claim 27, wherein the length of said connecting metallizations is substantially equal to the width of said sub-divided metallization strips.
Claim 39
Dependent Claim
271 words
A surface-wave resonator filter comprising: at least two reflector structures composed of metallization strips on a substrate of piezoelectric material; at least one interdigital transducer on said substrate of piezoelectric material in which a wave propagation in a direction x perpendicular to said metallization strips exists, said metallization strips having multiple interruptions in a transverse direction y relative to said wave propagation x, whereby for at least one of said reflector structures for at least a portion thereof, at least a plurality of said metallization strips are provided with said interruptions distributed relative to one another in said direction y of said metallization strips, thereby dividing these metallization strips into sub-sections; said reflector structure having the same plurality of interruptions of said metallization strips at least in a region of a portion of said reflector structure in a direction of said wave propagation direction x; said portion divided into a plurality of zones parallel to said wave propagation direction x which is equal in number to the plurality of interruptions and respectively only one interruption of a respectively sub-divided metallization strip present in the region of each and every one of these zones, said interruptions arranged in a random distribution relative to one another within a respective zone; connecting metallization proceeding in the direction of the wave propagation direction x provided between neighboring sub-sections of neighboring metallization strips, a respective sub-section of a metallization strip being electrically connected to a respectively neighboring sub-section of a neighboring metallization strip with these connecting metallizations, whereby no connecting metallizations are present which provide electrical connection between two-sections of one and the same metallization strip;
Claim 40
Dependent Claim
271 words
A surface-wave resonator filter comprising: at least two reflector structures composed of metallization strips on a substrate of piezoelectric material; at least one interdigital transducer on said substrate of piezoelectric material in which a wave propagation in a direction x perpendicular to said metallization strips exists, said metallization strips having multiple interruptions in a transverse direction y relative to said wave propagation x, whereby for at least one of said reflector structures for at least a portion thereof, at least a plurality of said metallization strips are provided with said interruptions distributed relative to one another in said direction y of said metallization strips, thereby dividing these metallization strips into sub-sections; said reflector structure having the same plurality of interruptions of said metallization strips at least in a region of a portion of said reflector structure in a direction of said wave propagation direction x; said portion divided into a plurality of zones parallel to said wave propagation direction x which is equal in number to the plurality of interruptions and respectively only one interruption of a respectively sub-divided metallization strip present in the region of each and every one of these zones, said interruptions arranged in a random distribution relative to one another within a respective zone; connecting metallization proceeding in the direction of the wave propagation direction x provided between neighboring sub-sections of neighboring metallization strips, a respective sub-section of a metallization strip being electrically connected to a respectively neighboring sub-section of a neighboring metallization strip with these connecting metallizations, whereby no connecting metallizations are present which provide electrical connection between two-sections of one and the same metallization strip;
Claim 41
Dependent Claim
18 words
The surface-wave resonator filter described in claim 35, wherein said reflector structure also has a portion without interruptions.
Claim 42
Dependent Claim
21 words
The surface-wave resonator filter described in claim 35, wherein the number of interruptions is in the range of 2 to 5.
Claim 43
Dependent Claim
21 words
The surface-wave resonator filter described in claim 35, wherein the connecting metallizations of respectively end-residing sub-sections are fashioned as bus bars.
Claim 44
Dependent Claim
28 words
The surface-wave resonator filter described in claim 35, wherein the interruptions of the metallization strips are dimensioned roughly of the size of the width of the metallization strips.
Claim 45
Dependent Claim
36 words
The surface-wave resonator filter described in claim 35, wherein the connecting metallizations are dimensioned with a width (transversely relative to the wave propagation direction (x)) of about the size of the width of the metallization strips.
Claim 46
Dependent Claim
243 words
A surface-wave resonator filter comprising: piezoelectric substrate; at least two reflector structures having metallization strips on said substrate; at least one interdigital transducer on said substrate and adjacent said reflector structures in which a wave propagation in a direction x perpendicular to said metallization strip exists; said metallization strips of at least one of said reflector structures having multiple interruptions in a transverse direction y relative to said wave propagation direction x; at least a portion of said one of said reflector structures having said interruptions distributed relative to one another in said direction y of said metallization strips to define sub-sections of said metallization strips thereby defining a sub-divided metallization strip; said one of reflector structures having the same plurality of interruptions for each of said metallization strips at least in a region of said portion of said one of said reflector structures in said wave propagation direction x; said portion divided into a plurality of zones parallel to said wave propagation direction x which is equal in number to said plurality of interruptions, only one interruption of said sub-divided metallization strip present in each of said zones, said interruptions within a respective zone arranged in a random distribution relative to one another; and connecting metallizations parallel to said wave propagation direction x provided between neighboring sub-sections of neighboring sub-divided metallization strips to electrically connect said neighboring sub-sections such that no two sub-sections of the same sub-divided metallization strip are electrically connected.
Claim 47
Dependent Claim
243 words
A surface-wave resonator filter comprising: piezoelectric substrate; at least two reflector structures having metallization strips on said substrate; at least one interdigital transducer on said substrate and adjacent said reflector structures in which a wave propagation in a direction x perpendicular to said metallization strip exists; said metallization strips of at least one of said reflector structures having multiple interruptions in a transverse direction y relative to said wave propagation direction x; at least a portion of said one of said reflector structures having said interruptions distributed relative to one another in said direction y of said metallization strips to define sub-sections of said metallization strips thereby defining a sub-divided metallization strip; said one of reflector structures having the same plurality of interruptions for each of said metallization strips at least in a region of said portion of said one of said reflector structures in said wave propagation direction x; said portion divided into a plurality of zones parallel to said wave propagation direction x which is equal in number to said plurality of interruptions, only one interruption of said sub-divided metallization strip present in each of said zones, said interruptions within a respective zone arranged in a random distribution relative to one another; and connecting metallizations parallel to said wave propagation direction x provided between neighboring sub-sections of neighboring sub-divided metallization strips to electrically connect said neighboring sub-sections such that no two sub-sections of the same sub-divided metallization strip are electrically connected.
Claim 48
Dependent Claim
20 words
The surface-wave resonator described in claim 41, wherein said reflector structure has a portion without interruption in metallization strips thereof.
Claim 49
Dependent Claim
20 words
The surface-wave resonator described in claim 41, wherein the number of interruptions in sub-divided metallization strip is at least 2.
Claim 50
Dependent Claim
22 words
The surface-wave resonator described in claim 41, wherein the number of interruptions in said sub-divided metallization strip is not greater than 5.
Claim 51
Dependent Claim
24 words
The surface-wave resonator described in claim 41, wherein said connecting metallization of end-residing sub-sections of said sub-divided metallization strips are fashioned as bus bars.
Claim 52
Dependent Claim
25 words
The surface-wave resonator described in claim 41, wherein the width of said connecting metallizations is substantially equal to the width of said sub-divided metallization strips.
Claim 53
Dependent Claim
25 words
The surface-wave resonator described in claim 41, wherein the length of said connecting metallization is substantially equal to the width of said sub-divided metallization strips.
References Cited (Backward Citations)
US4340834A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1991-07-26 | 1992-01-25 | 1992-07-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-07-26 | 1996-01-25 | 1996-07-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-07-26 | 2000-01-25 | 2000-07-26 | $7700.00 | Window Closed / Lapsed |