Title:
SURFACE ACOUSTIC WAVE FILTER
Document Type and Number:
Japanese Patent JP3487772
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To miniaturize a surface acoustic wave filter length in the propagation direction of surface acoustic waves and also improve the square of frequency characteristics.
SOLUTION: This surface acoustic wave filter is composed of a piezoelectric substrate 6, plural surface acoustic wave propagation paths 7 and 8 which is present parallelly to each other on the piezoelectric substrate, and a coupler 3 for coupling the surface acoustic wave propagation paths. At least on one surface acoustic wave propagation path, an input interdigital transducer 1 and a first reflector 4 are arranged interposing the coupler. At least on one of the other surface acoustic wave propagation path, an output interdigital transducer 2 and a second reflector 5 are arranged interposing the coupler.
Inventors:
Jun Tsutsumi
Takashi Matsuda
Osamu Igata
Yoshio Sato
Takashi Matsuda
Osamu Igata
Yoshio Sato
Application Number:
JP30116198A
Publication Date:
January 19, 2004
Filing Date:
October 22, 1998
Export Citation:
Assignee:
富士通株式会社
International Classes:
H03H9/25; H03H9/64; H03H9/145; (IPC1-7): H03H9/145; H03H9/25
Domestic Patent References:
| JP5039445A | ||||
| JP5518141A | ||||
| JP1190112A | ||||
| JP5235686A | ||||
| JP5934712A | ||||
| JP5110376A | ||||
| JP60112307A | ||||
| JP5199448A | ||||
| JP55687A | ||||
| JP59214314A | ||||
| JP61208306A | ||||
| JP918282A | ||||
| JP5501486A |
Other References:
【文献】米国特許3965446(US,A)
【文献】米国特許3882430(US,A)
【文献】米国特許4155056(US,A)
【文献】米国特許4737743(US,A)
【文献】米国特許3836876(US,A)
【文献】米国特許4130813(US,A)
【文献】米国特許3882430(US,A)
【文献】米国特許4155056(US,A)
【文献】米国特許4737743(US,A)
【文献】米国特許3836876(US,A)
【文献】米国特許4130813(US,A)
Attorney, Agent or Firm:
Shintaro Nogawa
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