Title:
ELASTIC WAVE FILTER DEVICE, MULTIPLEXER, AND COMPOUND FILTER DEVICE
Document Type and Number:
WIPO Patent Application WO/2018/225650
Kind Code:
A1
Abstract:
Provided is an elastic wave filter device in which degradation of filter characteristics due to transverse mode ripple does not readily occur. An elastic wave filter device 1 provided with at least one series-arm resonator S1, S2 and parallel-arm resonator P1, P2. The series-arm resonator S1, S2 and the parallel-arm resonator P1, P2 comprise elastic wave resonators. An IDT electrode of at least one series-arm resonator S1, S2 is an apodized IDT electrode subjected to intersection width weighting. In an IDT electrode of the parallel-arm resonator P1, P2, an intersecting part has a central region and low-sound-velocity regions provided on both outer sides of the central region. The sound velocity of elastic waves in the low-sound-velocity regions is set so as to be lower than the sound velocity of elastic waves in the central region. High-sound-velocity regions in which the sound velocity of elastic waves is higher than that in the low-sound-velocity regions are provided on the outer side of the low-sound-velocity regions.
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Inventors:
TAKATA TOSHIAKI (JP)
Application Number:
PCT/JP2018/021208
Publication Date:
December 13, 2018
Filing Date:
June 01, 2018
Export Citation:
Assignee:
MURATA MANUFACTURING CO (JP)
International Classes:
H03H9/145; H03H9/64; H03H9/72
Domestic Patent References:
| WO2016111262A1 | 2016-07-14 | |||
| WO2011115014A1 | 2011-09-22 | |||
| WO2015018252A1 | 2015-02-12 |
Foreign References:
| JP2012186808A | 2012-09-27 | |||
| JP2017085262A | 2017-05-18 | |||
| JP2009027689A | 2009-02-05 |
Attorney, Agent or Firm:
MIYAZAKI & METSUGI (JP)
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