Title:
弾性表面波共振子
Document Type and Number:
Japanese Patent JP4059152
Kind Code:
B2
Abstract:
In a substrate in which a reflection coefficient gamma of a surface acoustic wave per electrode is small, the invention obtains a Q value or a CI value level, which is equivalent to or higher than that of a related art product, at a device size which is equivalent to the related art product which addresses the problem that the size of a surface acoustic wave resonator becomes larger. A surface acoustic wave resonator includes one interdigital transducer to excite a surface acoustic wave in a propagation direction x on a piezoelectric plate and a pair of reflectors arranged on both sides thereof in the propagation direction. The interdigital transducer is divided into three regions. The electrode fingers of the interdigital transducer of each region are formed at a fixed pitch which differs within 2%. The surface acoustic wave resonator possesses a single peak response. The form in which a vibration displacement envelope amplitude in the interdigital transducer region is normalized is a form which takes a maximum value 1 at the center position, which smoothly takes a value in a range of 0.33 to 0.53 at a position ¼ from both ends, and which smoothly takes a value in a range of 0.048 to 0.177 at positions at both ends.
Inventors:
High Michiaki
Maeda Yoshio
Takashi Yamazaki
Keigo Iizawa
Maeda Yoshio
Takashi Yamazaki
Keigo Iizawa
Application Number:
JP2003172107A
Publication Date:
March 12, 2008
Filing Date:
June 17, 2003
Export Citation:
Assignee:
Seiko Epson Corporation
International Classes:
H01L41/09; H03H9/145; H01L41/18; H03H9/02; H03H9/25
Domestic Patent References:
| JP10335966A |
Attorney, Agent or Firm:
Masahiko Ueyanagi
Fujitsuna Hideyoshi
Osamu Suzawa
Fujitsuna Hideyoshi
Osamu Suzawa