Optical glass

Patent metadata

Field	Value
Publication number	US-10442722-B2
Application number	US-201615751295-A
Country	US
Kind code	B2
Filing date	Aug 10, 2016
Priority date	Aug 14, 2015
Publication date	Oct 15, 2019
Grant date	Oct 15, 2019

Abstract

A high refraction low dispersion optical glass, the components thereof including, by weight percentage: B2O3: 1-30%; SiO2: 0-20%; La2O3: 25-55%; Gd2O3: 5-40%; Y2O3: 0-25%; Yb2O3: 0-10%; Ta2O5: 0-10%; Nb2O5: 1-30%; TiO2: 0-10%; ZrO2: 0.5-20%; WO3: 0-10%; ZnO: 0-15%; R2O: 0-10%; RO: 0-10%; Al2O3: 0-10%; GeO2: 0-10%; Bi2O3: 0-10%. A high refraction low dispersion environmentally friendly optical glass having excellent light transmittance may be obtained by reducing the Ta2O5 content within the glass components and introducing suitable amounts of rare earth oxide components having a high refraction low dispersion effect.

First claim

The invention claimed is:

1. An optical glass comprising by weight percentage: B 2 O 3 : 1-30%; SiO 2 : 0-20%; La 2 O 3 : 25-55%; Gd 2 O 3 : 5-40%; Y 2 O 3 : 0-25%; Yb 2 O 3 : 0-10%; Ta 2 O 5 : 0-10%; Nb 2 O 5 : 1-30%; TiO 2 : 0-10%; TiO 2 /Nb 2 O 5 : less than 0.25; ZrO 2 : 0.5-20%; WO 3 : 0-10%; ZnO: 0-15%; (ZnO+Y 2 O 3 )/La 2 O 3 : less than 0.5; R 2 O: 0-10%, in which R 2 O is at least one of Li 2 O, Na 2 O or K 2 O; RO: 0-10%, in which, RO is at least one of BaO, SrO, MgO or CaO; Al 2 O 3 : 0-10%; GeO 2 : 0-10%; Bi 2 O 3 : 0-10%; the glass contains no PbO; the glass has a refractive index of from 1.88 to 1.91, and an Abbe number of 35-45,
wherein
Nb 2 O 5 /(Nb 2 O 5 +TiO 2 +ZrO 2 ) is 0.4-0.519;
(Nb 2 O 5 +Ta 2 O 5 +ZrO 2 )/(SiO 2 +B 2 O 3 ) is 0.6-0.768; and
Nb 2 O 5 is greater than ZrO 2 .

2. The optical glass according to claim 1 , optionally containing at least one of: Sb 2 O 3 : 0-1%; SnO 2 : 0-1%; or CeO 2 : 0-1%.

3. The optical glass according to claim 2 , wherein B 2 O 3 : 5-25%; SiO 2 : 0.1-15%; La 2 O 3 : 30-52%; Gd 2 O 3 : 5-35%; Y 2 O 3 : 1-20%; Ta 2 O 5 : 0-5%; Nb 2 O 5 : 2-25%; TiO 2 : 0.1-5%; ZrO 2 : 1-15%; WO 3 : 0-5%; ZnO: 0-10%; R 2 O: 0-5%; RO: 0-5%; Al 2 O 3 : 0-5%; GeO 2 : 0-5%; Bi 2 O 3 : 0-5%; Sb 2 O 3 : 0-0.5%; SnO 2 : 0-0.5%; and CeO 2 : 0-0.5%.

4. The optical glass according to claim 1 , wherein SiO 2 /(SiO 2 +B 2 O 3 ) is below 0.5; Y 2 O 3 /(La 2 O 3 +Gd 2 O 3 +Y 2 O 3 ) is below 0.2, and (ZnO+Y 2 O 3 )/La 2 O 3 is in the range of 0.05-0.3.

5. The optical glass according to claim 1 , wherein SiO 2 /(SiO 2 +B 2 O 3 ) is 0.25-0.4; Y 2 O 3 /(La 2 O 3 +Gd 2 O 3 +Y 2 O 3 ) is 0.05-0.12;
Nb 2 O 5 /(Nb 2 O 5 +TiO 2 +ZrO 2 ) is 0.48-0.519; and (ZnO+Y 2 O 3 )/La 2 O 3 is of 0.08-0.15.

6. The optical glass according to claim 1 , wherein WO 3 : 0-4%.

7. The optical glass according to claim 1 , wherein the glass has an Abbe number from 37 to 41.

8. The optical glass according to claim 1 , wherein the glass has a refractive index from 1.88 to 1.90, and an Abbe number from 38 to 40.

9. A glass preform made of the optical glass according to claim 1 .

10. An optical element made of the optical glass according to claim 1 .

Assignees

• Cdgm Glass Co Ltd

Inventors

• Sun Wei

Classifications

• C03C3/155

  containing zirconium, titanium, tantalum or niobium · CPC title

• C03C3/068 Primary

  containing rare earths · CPC title