Title:
SURFACE ACOUSTIC WAVE FILTER DEVICE
Document Type and Number:
Japanese Patent JP3368087
Kind Code:
B2
Abstract:
PURPOSE: To extend a signal pass band width without increase in an insertion loss.
CONSTITUTION: An interdigital input electrode 11 and an interdigital output electrode 12 are arranged in series on a piezoelectric substrate 10 in a propagation direction of a surface acoustic wave and a reflector 13 (14) is arranged to the outside of the electrode 11(12). The distance between the input electrode 11 and the output electrode 12 is selected to be a multiple of 18 or more of a 1/2 wavelength of a propagation surface acoustic wave. A band pass characteristic is obtained by utilizing three kinds of resonance comprising resonance between both the reflectors 13, 14, resonance between both the electrodes 11, 12 and each internal resonance of both the electrodes 11, 12.
Inventors:
Tsutomu Miura
Tomoharu Inoue
Tomoharu Inoue
Application Number:
JP6085595A
Publication Date:
January 20, 2003
Filing Date:
March 20, 1995
Export Citation:
Assignee:
Maruyasu Industry Co., Ltd.
International Classes:
H03H9/145; H03H9/25; H03H9/64; (IPC1-7): H03H9/64; H03H9/145; H03H9/25
Domestic Patent References:
| JP63283309A | ||||
| JP6212206A | ||||
| JP6230413A |
Other References:
山本泰司，複合縦モード共振器型ＳＡＷフィルタ，電子情報通信学会論文誌，１９９３年２月２５日，ＶＯＬ．Ｊ７６−Ａ，Ｎｏ．２（第３０２号，ｐ．２１９−２２６
Attorney, Agent or Firm:
Shoichi Hase (2 outside)