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:
Jun. 11, 2002
Filed:
Dec. 07, 1999
Hiroshi Tomohiro, Shiga-ken, JP;
Naoki Fujii, Omihachiman, JP;
Murata Manufacturing Co., Ltd., Nagaokakyo, JP;
Abstract
In a method of polarization-treating a piezoelectric material, the maximum polarization degree &Dgr;f achieved by 180° rotation is determined. A residual polarization degree &Dgr;f as a target value and the maximum polarization degree &Dgr;f are compared. In the case of &Dgr;f≦&Dgr;f , a determination is made as to the temperature T for obtaining the polarization degree &Dgr;f made up solely of the polarization degree achieved by 180° rotation. Half-polarization is carried out at the temperature T , and aging is conducted at the temperature T , whereby a piezoelectric material of which the ratio of the polarization achieved by 180° rotation is 100%, which is stable thermally with passage of time, and has a polarization degree &Dgr;f correctly coincident with a target value, can be obtained.