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. 13, 2004
Filed:
May. 30, 2001
TDK Corporation, Tokyo, JP;
Abstract
The invention aims to solve the problem of prior art EL devices that undesirable defects form in dielectric layers, and especially the problems of EL devices having dielectric layers of lead-base dielectric material including a lowering, variation and change with time of the luminance of light emission, and thereby provide an EL device ensuring high display quality and a method for manufacturing the same at a low cost. Such objects are achieved by an EL device comprising at least an electrically insulating substrate ( ) and a structure including an electrode layer ( ), a dielectric layer ( ), a light emitting layer ( ) and a transparent electrode layer ( ) stacked on the substrate ( ), wherein the dielectric layer is a laminate including a first thick-film ceramic high-permittivity dielectric layer ( ) whose composition contains at least lead, a second high-permittivity layer ( ) whose composition contains at least lead, and a third high-permittivity layer ( ) whose composition is free of at least lead.