EP0093956A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
A dielectric filter
Assignee: Oki Electric Industry Co Ltd
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Filing: 1983-04-27
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Granted: —
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Expires: 2003-04-27
Abstract
Abstract A dielectric filter (Fig. 16) for frequencies higher than VHF band comprising a closed conductive housing (112), a pair of input and output means provided at both the extreme ends of said housing (112), a dielectric body (111) with a plurality of linear parallel grooves (118) arranged in said housing (112), a plurality of conductive linear means (113) with the length of approximately 1/4 wavelength mounted in said dielectric body (111) between said grooves (118) so that one end of said resonators (113) is fixed to the common plane of the housing (112), a capacitor means (114, 115) provided between the other end of resonators (111, 113, 118) and said conductive housing (112) so that an electrode (115) of said capacitor may be trimmed by laser beam to adjust the resonating frequency of each of said resonators (111, 113, 118) and a plurality of conductive rods (137) provided in said grooves (118) for improving the spurious characteristics of the filter.
Inventors
- 👤 Atsushi Fukasawa
- 👤 Kenichiro Hosoda
- 👤 Takuro Sato
- 👤 Tatumasa Yoshida
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 17:39
CPC Classifications
H; H01; H01P; H01P1/00; H01P1/20; H01P1/201; H01P1/205; H01P1/2056
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
5 words
(1) A dielectric filter comprising;
Claim 2
Dependent Claim
211 words
a) a conductive closed housing, b) at least two resonators fixed in said housing, c) an input means for coupling one end resonator of said at least two resonators to an external circuit, and an output means for coupling the other end resonator of said at least two resonators to an external circuit, d) each resonator comprising an elongated linear inner conductor one end of which is fixed commonly at the bottom of said housing, and the other end of which is free standing, and a dielectric body surrounding said inner conductor, e) the thickness of said dielectric body surrounding said inner conductor being sufficient to hold all the electromagnetic energy in the dielectric body except for the energy for coupling between two adjacent resonators, and f) an air gap is provided between adjacent resonators; CHARACTERIZED IN THAT g) said dielectric body (111) surrounding inner conductor (113) is a bulk body common to all the resonators with a groove (118) between two adjacent resonators, and said groove (118) operates as said air gap between resonators for effecting coupling between the resonators, h) a capacitor with a trimming electrode (115) is provided at the free end of the inner conductor (113) of each resonator for finely adjusting resonating frequency of the resonator.
Claim 3
Dependent Claim
37 words
(2) A dielectric filter according to claim 1, further comprising an elongated conductive means (136, 137) provided in said groove (118) so that said elongated conductive means is perpendicular to an inner conductor (113) of a resonator.
Claim 4
Dependent Claim
78 words
(3) A dielectric filter according to claim 1, wherein said capacitor has an opaque dielectric plate (114) and a pair of electrodes (115,116) attached on both the surfaces of said dielectric plate (114), one electrode (116) is electrically coupled with an inner conductor (113) of a resonator, and another electrode (115) is grounded to the housing (112), and said latter electrode (115) is subject to be trimmed by a laser beam for adjusting the capacitance of the capacitor.
Claim 5
Dependent Claim
29 words
(4) A dielectric filter according to claim 3, wherein said electrode (115) is separated to a plurality of cells (115a) each of which is coupled electrically with one another.
Claim 6
Dependent Claim
44 words
(5) A dielectric filter according to claim 3, wherein said dielectric plate (114) is provided by a part of the bulk dielectric body (111) so that thin dielectric portion (111a) is provided between the electrode (115) and the top of the inner conductor (113).
Claim 7
Dependent Claim
41 words
(6) A dielectric filter according to claim 1, wherein a cover (119) of said housing (112) confronting said electrode (115) is transparent so that a trimming of the electrode (115) by a laser beam is effected by an external laser beam.
Claim 8
Dependent Claim
45 words
(7) A dielectric filter according to claim 1, wherein said capacitor has a conductive layer (120, 122, 123) attached on a free standing end of the dielectric body (111), and said conductive layer is subject to be trimmed for adjusting the capacitance of the capacitor.
Claim 9
Dependent Claim
46 words
(8) A dielectric filter according to claim 7, wherein said conductive layer is composed of a first layer (122) coupled with an inner conductor (113) of a resonator, and a second layer coupled with the housing (112), and the second layer (120) is subject to trimming.
Claim 10
Dependent Claim
43 words
(9) A dielectric filter according to claim 7, wherein said conductive layer has a layer (123) coupled with an inner conductor (113), said layer (123) is subject to be trimmed, and the capacitance is provided between said layer (123) and the housing (112).
Claim 11
Dependent Claim
18 words
(10) A dielectric filter according to claim 2, wherein said elongated conductive means is a conductive film (136).
Claim 12
Dependent Claim
18 words
(11) A dielectric filter according to claim 2, wherein said elongated conductive means is a conductive rod (137).
Claim 13
Dependent Claim
28 words
(12) A dielectric filter according to claim 2, wherein said elongated conductive means (136, 137) is provided around the middle portion of the height (H) of a resonator.
Claim 14
Dependent Claim
23 words
(13) A dielectric filter according to claim 1, wherein said dielectric body is made of M g T i O 3 type ceramics.
Claim 15
Dependent Claim
18 words
(14) A dielectric filter according to claim 3, wherein said opaque dielectric plate (114) is made of alumina.
References Cited (Backward Citations)
No citation records indexed.
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