Title:
ELASTIC WAVE FILTER, BRANCHING FILTER, AND COMMUNICATION DEVICE
Document Type and Number:
WIPO Patent Application WO/2019/124316
Kind Code:
A1
Abstract:
According to the present invention, a filter body has a serial arm, and one or more parallel resonators in such a manner as to be connected in a ladder form. The serial arm includes a plurality of serial resonators that are connected in series. The difference in resonance frequencies between the serial resonators is less than half of the difference between the resonance frequency and the anti-resonance frequency of each of the serial resonators. The serial arm has a first split arm that extends from one side to the other side on a piezoelectric substrate in a prescribed direction, and a second split arm that returns from the other side of the first split arm to extend toward the one side. A shield conductor has a portion that is positioned between at least one of the serial resonators included in the first split arm and at least one of the serial resonators included in the second split arm.
Inventors:
ITO MOTOKI (JP)
NAGAMINE SHIGEHIKO (JP)
NAKAMURA TOMOFUMI (JP)
NAGAMINE SHIGEHIKO (JP)
NAKAMURA TOMOFUMI (JP)
Application Number:
PCT/JP2018/046381
Publication Date:
June 27, 2019
Filing Date:
December 17, 2018
Export Citation:
Assignee:
KYOCERA CORP (JP)
International Classes:
H03H9/64; H03H9/72
Foreign References:
| JP2000174586A | 2000-06-23 | |||
| JP2015070489A | 2015-04-13 | |||
| JPH07154201A | 1995-06-16 |
Attorney, Agent or Firm:
IIJIMA, YASUHIRO (JP)
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