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:
Sep. 21, 2004
Filed:
Mar. 27, 2002
Kabushiki Kaisha Ohara, Kanagawa-ken, JP;
Abstract
There is provided a glass-ceramic which is suitable for use as a light filter. The glass-ceramic has Young's modulus (GPa) within a range from 95 to 120 and includes 5.3-8 weight percent of Al O , 0.5-3.5 weight percent of ZrO and 71-81 weight percent of SiO , based respectively on the total content of the oxides. The glass-ceramic preferably has, as its predominant crystal phases, (a) lithium disilicate (Li O. SiO ) and (b) at least one of &agr;-quartz (&agr;-SiO ) and &agr;-quartz solid solution (&agr;-SiO solid solution), has specific gravity within a range from 2.4 to 2.6 and has a coefficient of thermal expansion within a range from 65×10 /° C. to 130×10 /° C. within a temperature range from −50° C. to +70° C.