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:
Dec. 18, 2001
Filed:
Feb. 09, 2001
Sumitomo Special Metals Co., Ltd., Osaka, JP;
Abstract
A microwave dielectric ceramic composition exhibiting excellent relative permitting (∈) and high Qf-value, enabling the temperature coefficient of resonance frequency to be easily adjusted, and being best suited for a filter having cavities made of, e.g., iron or copper exhibiting a large temperature coefficient of resonance frequency. The ceramic is of a BaO—TiO,—Nd,O,—Sm,O,ceramic, type wherein Nd,O,is partly substituted by Bi,O,, Nd,O,is Partly substituted by Ln,O,(where Ln is La, Ce or Pr) and, the above substituted Ln,O,is partly substituted by EU,O,to improve the properties so that ∈ is 82.5 to 92.5, Qf is 6000 to 7300 GHz and &tgr;f is 10-20 ppm/° C. This makes it possible to impart favorable electric characteristics to resonance cavities of various materials and sizes.