| (19) |
 |
|
(11) |
EP 0 324 512 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
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26.07.1989 Bulletin 1989/30 |
| (43) |
Date of publication A2: |
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19.07.1989 Bulletin 1989/29 |
| (22) |
Date of filing: 27.04.1983 |
|
| (51) |
International Patent Classification (IPC)4: H01P 1/205 |
|
| (84) |
Designated Contracting States: |
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DE FR GB NL SE |
| (30) |
Priority: |
10.05.1982 JP 76565/82
10.05.1982 JP 76566/82
|
| (62) |
Application number of the earlier application in accordance with Art. 76 EPC: |
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83104137.1 / 0093956 |
| (71) |
Applicant: Oki Electric Industry Company, Limited |
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Tokyo 105 (JP) |
|
| (72) |
Inventors: |
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- Fukasawa, Atsushi
Oki Electric Industry Co., Ltd.
Minato-ku
Tokyo (JP)
- Hosoda, Kenichiro
Oki Electric Industry Co., Ltd.
Minato-ku
Tokyo (JP)
- Sato, Takuro
Oki Electric Industry Co., Ltd.
Minato-ku
Tokyo (JP)
- Yoshida, Tatumasa
Electric Industry Co., Ltd.
Minato-ku
Tokyo (JP)
|
| (74) |
Representative: Kirschner, Klaus Dieter, Dipl.-Phys. et al |
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Patentanwälte
Herrmann-Trentepohl, Kirschner,
Grosse, Bockhorni & Partner
Forstenrieder Allee 59
D-81476 München
D-81476 München (DE) |
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(57) 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) wwith 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 a 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.