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:
Aug. 09, 2011
Filed:
Jun. 29, 2004
Xuelu Zou, Akishima, JP;
Yoshiko Kasuga, Koganei, JP;
Yasuhiro Fujiwara, Akishima, JP;
Hoya Corporation, Tokyo, JP;
Abstract
Preforms for precision press molding made of optical glass, optical elements, and methods of manufacturing the same are provided. The preforms are suited to precision press molding having a broad range of dispersion characteristics, a low glass transition temperature, a low sag point, and good resistance to devitrification while containing no PbO. The optical element is obtained by precision press molding the preform. One example of the preform has a refractive index (nd) of greater than or equal to 1.7 and an Abbé number (vd) of less than or equal to 32. The other example of the preform has an Abbé number (vd) exceeding 32.