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:
Jan. 04, 1994
Filed:
May. 29, 1992
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A high-frequency filter of the type having a plurality of resonators open at least at one end thereof, a dielectric board forming an input/output coupling and an interstage coupling, and a case for holding therein the resonators and the dielectric board, wherein the dielectric board is made of a ceramic having a critical stress intensity factor K.sub.1c of not less than 5 MPa.multidot.m.sup.1/2 and a dielectric dissipation factor tan. .delta. of not exceeding 1% in a working frequency band of said high-frequency filter, and wherein electrodes are provided on the dielectric board to form an input/output coupling capacity and an interstage coupling capacity. The high-frequency filter of the foregoing construction has the advantage of an excellent mechanical strength which is capable of withstanding severe mechanical loads such as falling impacts or various stresses.