The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 18, 2010
Filed:
Jan. 24, 2008
Tomohiro Iwasaki, Osaka, JP;
Hiroshi Nakatsuka, Osaka, JP;
Keiji Onishi, Osaka, JP;
Takehiko Yamakawa, Osaka, JP;
Tomohide Kamiyama, Osaka, JP;
Tomohiro Iwasaki, Osaka, JP;
Hiroshi Nakatsuka, Osaka, JP;
Keiji Onishi, Osaka, JP;
Takehiko Yamakawa, Osaka, JP;
Tomohide Kamiyama, Osaka, JP;
Panasonic Corporation, Osaka, JP;
Abstract
A dual mode piezoelectric filter includes a piezoelectric material layer composed of a piezoelectric thin film of the high-cut type formed on a substrate, a first electrode and a second electrode formed on one of the major surfaces of the piezoelectric material layer with a gap provided therebetween, a third electrode formed on the other major surface of the piezoelectric material layer opposite to the first electrode, the second electrode, and the gap, and an interelectrode mass load element formed in the gap or at a position opposite to the gap on a surface of the piezoelectric material layer. The relationships (ρh)≦(ρa×ha) and (ρh)≦(ρa×ha) are satisfied, where his the thickness and ρis the density of the first electrode, his the thickness and ρis the density of the second electrode, and ha is the thickness and ρa is the density of the interelectrode mass load element. A filter characteristic with a smooth passband and low losses is obtained.