Optical glass and use thereof

Patent metadata

Field	Value
Publication number	US-9643880-B2
Application number	US-201414911340-A
Country	US
Kind code	B2
Filing date	Aug 22, 2014
Priority date	Aug 23, 2013
Publication date	May 9, 2017
Grant date	May 9, 2017

Abstract

An optical glass that is oxide glass, containing Si 4+ , B 3+ , La 3+ , Ti 4+ , Nb 5+ , and Zr 4+ ; containing, denoted as cation %, Si 4+ and B 3+ of 5 to 55% in total, La 3+ of 10 to 50%, with a total content of La 3+ , Gd 3+ , Y 3+ and Yb 3+ ≦70%, and Ti 4+ , Nb 5+ , Ta 5+ and W 6+ of 22 to 55% in total, with a content of Ti 4+ ≦22%, wherein [Si 4+ /(Si 4+ +B 3+ )]≦0.40; the total content of La 3+ , Gd 3+ , Y 3+ , Yb 3+ , Zr 4+ , Ti 4+ , Nb 5+ , Ta 5+ , W 6+ and Bi 3+ ≧65%; [Y 3+ /(La 3+ +Gd 3+ +Y 3+ +Yb 3+ )]≦0.12; [Ba 2+ /(La 3+ +Gd 3+ +Y 3+ +Yb 3+ )]≦0.40; [(Zr 4+ +Ti 4+ +Nb 5+ +Ta 5+ +W 6+ )/Zr 4+ ]≧2; (Ti 4+ /B 3+ )≧0.85; and an Abbé number νd is in a range from 23 to 35, and a refractive index nd satisfies nd≧2.205−(0.0062×νd).

First claim

The invention claimed is:

1. Optical glass, which is oxide glass:
comprising Si 4+ , B 3+ , La 3+ , Ti 4+ , Nb 5+ , and Zr 4+ as essential components;
comprising, denoted as cation %;
Si 4+ and B 3+ of 5 to 35% in total,
La 3+ of 10 to 50%, with a total content of La 3+ , Gd 3+ , Y 3+ and Yb 3+ being from 11% to 70%, and
Ti 4+ , Nb 5+ , Ta 5+ and W 6+ of 22 to 55% in total, with a content of Ti 4+ being from 10% to 22%, wherein
a cation ratio of a content of Si 4+ to a total content of Si 4+ and B 3+, Si 4+ /(Si 4+ +B 3+ ), is from 0.10 to 0.40;
a total content of La 3+ , Gd 3+ , Y 3+ , Zr 4+ , Ti 4+ , Nb 4+ , Ta 5+ , W 6+ and Bi 3 + is equal to or more than 65%;
a cation ratio of a content of Y 3+ to a total content of La 3+ , Gd 3+ , Y 3+ and Yb 3 + , Y 3+ /(La 3+ +Gd 3+ +Y 3+ +Yb 3+ ), is equal to or less than 0.12;
a cation ratio of a content of Ba 2+ to a total content of La 3+ , Gd 3+ , Y 3+ and Yb 3+ , Ba 2+ /(La 3+ +Gd 3+ +Y 3+ +Yb 3+ ), is equal to or less than 0.40;
a cation ratio of a total content of Zr 4+ , Ti 4+ , Nb 5+ , Ta 5+ and W 6+ to a content of Zr 4+ , (Zr 4+ Ti 4+ +Ta 5+W 6+ )/Zr 4+ , is equal to or more than 2;
a cation ratio of a content of Ti 4+ to a content of B 3+ , Ti 4+ /B 3+ , is equal to or more than 0. 85; and
an Abbé number νd is in a range from 23 to 35, and a refractive index nd satisfies Expression (1) below,
nd≧ 2.205−(0.0062 ×νd )  (1).

2. The optical glass according to claim 1 , wherein a cation ratio of a total content of Nb 5+ and Ta 5+ to a total content of Ti 4 + , Nb 5+ , Ta 5+ and W 6+ , (Nb 5+ +Ta 5+ )/(Ti 4+ +Nb 5+ Ta 5+ +W 6+ ), is from 0.10 to 0.41.

3. The optical glass according to claim 1 , which comprises Zr 4+ in an amount equal to or more than 1 cation %.

4. A press-molding glass gob, which is comprised of the optical glass according to claim 1 .

5. An optical element blank, which is comprised of the optical glass according claim 1 .

6. An optical element, which is comprised of the optical glass according to claim 1 .

Assignees

• Hoya Corp

Inventors

• Negishi Tomoaki

Classifications

• G02B27/0025

  for optical correction, e.g. distorsion, aberration · CPC title

• G02B1/00

  Optical elements characterised by the material of which they are made; Optical coatings for optical elements · CPC title

• C03C3/068 Primary

  containing rare earths · CPC title