HIGH-REFRACTION GLASS HAVING LOW DENSITY

Abstract

An optical glass having a refractive index of more than 1.85, and glass articles comprising the optical glass, especially in the fields of optics and lenses, metaoptics and augmented reality (AR) are disclosed.

Claims

1. An optical glass having a refractive index n.sub.d of more than 1.85, an Abbe number v.sub.d of less than 35 and a temperature T.sub.max of not more than 1350 C., comprising at least SiO.sub.2 and TiO.sub.2, comprising less than 30.0 mol % of SiO.sub.2, less than 2.0 mol % of Nb.sub.2O.sub.5, less than 17 mol % of BaO and less than 5.0 mol % of Ln.sub.2O.sub.3, where Ln.sub.2O.sub.3Y.sub.2O.sub.3, La.sub.2O.sub.3, Gd.sub.2O.sub.3 and/or Yb.sub.2O.sub.3.

2. The optical glass of claim 1, wherein the glass has a molar ratio of (TiO.sub.2+ZrO.sub.2+2*Nb.sub.2O.sub.5+2*Ta.sub.2O.sub.5+2*Al.sub.2O.sub.3+SiO.sub.2+B.sub.2O.sub.3)/(R.sub.2O+RO+2*Ln.sub.2O.sub.3) of 1.5-3.5, where R.sub.2OLi.sub.2O, Na.sub.2O and/or K.sub.2O and ROMgO, CaO, SrO and/or BaO and Ln.sub.2O.sub.3Y.sub.2O.sub.3, La.sub.2O.sub.3, Gd.sub.2O.sub.3 and/or Yb.sub.2O.sub.3.

3. The optical glass of claim 1, wherein the glass has a product of Abbe number v.sub.d and density of less than 120 g/cm.sup.3.

4. The optical glass of claim 1, wherein the glass is essentially free of Nb.sub.2O.sub.5.

5. The optical glass of claim 1, wherein the glass contains more than 0 mol % to 15.0 mol % of BaO.

6. The optical glass of claim 1, wherein the glass has a total content of BaO and TiO.sub.2 of at least 35.0 mol % and/or not more than 70.0 mol %.

7. The optical glass of claim 1, wherein the glass has a total content of R.sub.2O, where R.sub.2OLi.sub.2O, Na.sub.2O and/or K.sub.2O, of 1.0 mol % to 20.0 mol %.

8. The optical glass of claim 1, wherein the glass has a total content of RO, where ROMgO, CaO, SrO and/or BaO, of 8.0 mol % to 31.0 mol % and/or a total content of MgO, CaO and SrO of 2.0 mol % to 25.0 mol %.

9. The optical glass of claim 1, wherein the glass has a total content of RO+R.sub.2O of 15.0 mol % to 40.0 mol %.

10. The optical glass of claim 1, wherein the glass contains from 0.5 mol % to 7.5 mol % of ZrO.sub.2.

11. The optical glass of claim 1, wherein the glass includes less than 10.0 mol % of ZnO.

12. The optical glass of claim 1, wherein the glass comprises the following components in mol %: TABLE-US-00013 SiO.sub.2 10.0-<30.0 B.sub.2O.sub.3 0-8.0 TiO.sub.2 + BaO 35.0-70.0 R.sub.2O + RO 15.0-40.0 ZnO <10.0 Ln.sub.2O.sub.3 <2.0.

13. The optical glass of claim 1, wherein the glass has a total content of SiO.sub.2 and B.sub.2O.sub.3 of 12.0 mol % to 25.0 mol %.

14. The optical glass of claim 1, wherein the glass contains less than 5.0 mol % of K.sub.2O.

15. The optical glass of claim 1, wherein the glass comprises the following components in mol %: TABLE-US-00014 SiO.sub.2 10.0-<30.0 B.sub.2O.sub.3 0-8.0 TiO.sub.2 + BaO 35.0-70.0 R.sub.2O 1.0-20.0 RO 8.0-31.0 R.sub.2O + RO 15.0-40.0 ZnO 7.5 ZrO2 0.5-7.5 Ln.sub.2O.sub.3 <1.0.

16. The optical glass of claim 1, wherein the glass comprises the following components in mol %: TABLE-US-00015 SiO.sub.2 12.0-28.0 B.sub.2O.sub.3 0-5.0 TiO.sub.2 + BaO 40.0-65.0 TiO.sub.2 35.0-65.0 R.sub.2O 2.0-17.0 Li.sub.2O 0-10.0 Na.sub.2O 0.5-15.0 K.sub.2O 0-5.0 RO 10.0-28.0 MgO 0-10.0 CaO 1.0-25.0 SrO 0-5.0 BaO 1.0-12.0 R.sub.2O + RO 20.0-35.0 ZnO 0-5.5 ZrO2 1.5-6.5 Ln.sub.2O.sub.3 <1.0.

17. The optical glass of claim 1, wherein the glass has an internal transmittance of at least 80% measured at a wavelength of 460 nm and a sample thickness of 10 mm.

18. A glass article comprising the optical glass of claim 1, in the form of a glass substrate, especially as a constituent of a stack of substrates for an optical component, especially in a pair of AR eyeglasses, a wafer, a lens, a rod lens, a prism or an asphere, and/or an optical waveguide, especially a fibre or plate.

Description

EXAMPLES

[0087] The compositions shown in Tables 1 to 4 below were melted and their properties were examined.

Compositions and Properties:

TABLE-US-00007 TABLE 1 mol % 1 2 3 4 5 6 7 B.sub.2O.sub.3 2.90 2.90 0.00 2.90 1.00 0.00 0.00 BaO 9.37 7.03 7.82 8.49 0.00 7.82 7.38 TiO.sub.2 47.67 47.67 50.92 47.49 47.87 50.92 50.83 Nb.sub.2O.sub.5 0.00 0.00 0.00 0.00 0.00 0.00 0.00 SiO.sub.2 17.40 17.40 17.88 17.41 18.04 17.88 17.88 Al.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 MgO 0.00 0.00 0.00 0.00 4.20 0.00 0.00 CaO 14.05 16.39 7.82 14.15 15.92 7.82 7.38 Li.sub.2O 0.00 0.00 1.17 0.00 0.00 0.00 0.00 Na.sub.2O 3.51 4.52 8.21 4.55 6.63 10.56 10.59 K.sub.2O 1.51 0.50 2.35 0.51 0.74 1.17 1.18 ZnO 0.00 0.00 0.00 0.94 0.88 0.00 0.94 SrO 0.00 0.00 0.00 0.00 1.11 0.00 0.00 As.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Y.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Sb.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 La.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Gd.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 ZrO.sub.2 3.59 3.59 3.83 3.57 3.60 3.83 3.83 Total 100.00 100.00 100.00 100.00 100.00 100.00 100.00 Properties n.sub.d 1.994 1.993 1.989 1.994 1.988 1.988 1.989 v.sub.d 20.5 20.8 20.1 20.6 20.6 20.2 20.1 Density [g/cm.sup.3] 3.73 3.67 3.65 3.73 3.47 3.66 3.65

TABLE-US-00008 TABLE 2 mol % 8 9 10 11 12 13 14 B.sub.2O.sub.3 0.00 0.94 1.05 1.04 0.00 0.00 0.00 BaO 7.38 7.42 8.46 8.46 8.47 7.38 8.36 TiO.sub.2 50.28 50.76 48.25 48.45 50.28 50.28 48.97 Nb.sub.2O.sub.5 0.00 0.00 0.00 0.00 0.00 0.00 0.00 SiO.sub.2 17.88 16.85 18.87 18.68 17.88 17.88 18.91 Al.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 MgO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 CaO 7.38 7.42 11.84 11.84 6.28 6.28 9.29 Li.sub.2O 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Na.sub.2O 10.59 10.66 7.05 6.48 10.59 10.59 8.45 K.sub.2O 1.18 1.18 0.00 0.56 1.18 1.18 0.84 ZnO 0.94 0.95 0.85 0.85 0.94 0.94 0.93 SrO 0.00 0.00 0.00 0.00 0.00 1.10 0.00 As.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Y.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Sb.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 La.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Gd.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 ZrO.sub.2 4.37 3.82 3.63 3.65 4.37 4.37 4.26 Total 100.00 100.00 100.00 100.00 100.00 100.00 100.00 Properties n.sub.d 1.987 1.988 1.992 1.992 1.987 1.982 1.991 v.sub.d 20.3 20.2 20.8 20.6 20.5 20.4 21.0 Density [g/cm.sup.3] 3.66 3.65 3.72 3.72 3.68 3.67 3.70

TABLE-US-00009 TABLE 3 mol % 15 16 17 18 19 20 21 B.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 BaO 8.47 8.52 8.31 8.36 4.42 8.31 3.38 TiO.sub.2 49.87 50.11 48.39 48.87 45.46 49.03 48.73 Nb.sub.2O.sub.5 0.00 0.00 0.00 0.00 0.00 0.00 0.00 SiO.sub.2 18.33 18.16 20.17 19.02 19.53 18.39 19.47 Al.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 MgO 0.00 0.00 0.00 0.00 5.85 0.00 1.31 CaO 6.28 5.84 11.37 9.29 14.57 9.44 12.94 Li.sub.2O 0.59 0.00 0.00 0.46 0.00 0.00 0.00 Na.sub.2O 10.24 10.89 7.02 7.99 5.57 8.78 8.82 K.sub.2O 0.94 0.95 0.00 0.84 0.00 0.66 0.56 ZnO 0.94 0.95 0.84 0.93 1.17 1.13 1.13 SrO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 As.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Y.sub.2O.sub.3 0.00 0.24 0.00 0.00 0.00 0.00 0.00 Sb.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 La.sub.2O.sub.3 0.00 0.00 0.26 0.00 0.00 0.00 0.00 Gd.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 ZrO.sub.2 4.34 4.36 3.64 4.25 3.42 4.26 3.67 Total 100.00 100.00 100.00 100.00 100.00 100.00 100.00 Properties n.sub.d 1.987 1.979 1.985 1.991 1.990 1.991 1.986 v.sub.d 20.8 20.3 20.4 20.6 21.2 21 20.4 Density [g/cm.sup.3] 3.69 3.67 3.69 3.71 3.61 3.71 3.54

TABLE-US-00010 TABLE 4 mol % 22 23 24 25 26 27 28 B.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 1.57 0.00 BaO 3.39 3.41 3.41 2.08 0.00 8.30 7.35 TiO.sub.2 48.68 47.32 46.62 48.65 48.50 49.25 46.64 Nb.sub.2O.sub.5 0.00 0.00 0.00 0.00 0.00 0.00 0.00 SiO.sub.2 18.39 20.67 21.42 19.37 19.17 17.74 21.61 Al.sub.2O.sub.3 1.02 0.00 0.00 0.00 0.00 0.00 0.69 MgO 1.32 1.92 1.92 1.32 1.34 0.00 0.00 CaO 12.99 14.72 14.72 13.03 13.57 9.44 5.94 Li.sub.2O 0.00 0.00 5.69 0.00 0.00 0.00 0.53 Na.sub.2O 8.85 7.11 1.42 8.97 9.08 8.77 12.61 K.sub.2O 0.56 0.00 0.00 0.47 0.48 0.66 0.00 ZnO 1.13 1.28 1.28 2.45 4.21 1.13 0.85 SrO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 As.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Y.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Sb.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 La.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Gd.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 ZrO.sub.2 3.66 3.56 3.51 3.66 3.65 3.14 3.78 Total 100.00 100.00 100.00 100.00 100.00 100.0 100.00 Properties n.sub.d 1.986 1.988 2.004 1.983 1.990 1.987 1.950 v.sub.d 20.4 20.7 20.5 20.3 20.1 20.2 21.0 Density [g/cm.sup.3] 3.56 3.56 3.60 3.53 3.49 3.69 3.60

TABLE-US-00011 TABLE 5 mol % 29 30 31 32 33 34 35 B.sub.2O.sub.3 0.00 0.00 3.50 6.84 0.00 0.00 0.00 BaO 6.98 8.48 8.05 14.53 8.48 7.89 0.00 TiO.sub.2 45.44 45.49 44.99 39.49 45.44 46.68 43.88 Nb.sub.2O.sub.5 0.00 0.00 0.00 0.00 0.00 0.00 0.00 SiO.sub.2 19.74 24.05 16.34 13.68 23.83 22.75 26.76 Al.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 MgO 4.14 0.00 3.63 4.00 0.00 0.00 0.69 CaO 13.19 5.60 12.98 16.35 5.76 4.90 6.95 Li.sub.2O 0.00 0.45 0.00 0.00 0.00 0.00 0.69 Na.sub.2O 5.21 10.11 5.23 0.00 10.56 11.74 15.29 K.sub.2O 0.33 0.80 0.33 0.00 0.80 0.88 1.39 ZnO 1.55 1.06 1.30 1.45 0.91 0.82 1.04 SrO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 As.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Y.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Sb.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 La.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Gd.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 ZrO.sub.2 3.42 3.96 3.65 3.67 4.22 4.34 3.30 Total 100.00 100.00 100.00 100.00 100.00 100.00 100.00 Properties n.sub.d 1.988 1.942 1.983 1.965 1.943 1.946 1.90 v.sub.d 20.7 20.3 20.8 23 22.3 20.9 22.6 Density [g/cm.sup.3] 3.71 3.61 3.71 3.93 3.61 3.58 3.24

TABLE-US-00012 TABLE 6 mol % 36 37 38 39 40 41 42 B.sub.2O.sub.3 1.14 0.00 3.75 4.61 0.00 0.00 4.926 BaO 8.02 1.14 13.66 14.59 7.91 7.43 16.285 TiO.sub.2 46.63 43.83 44.47 42.61 46.39 46.41 41.342 Nb.sub.2O.sub.5 0.00 0.00 0.00 0.00 0.00 0.00 0.000 SiO.sub.2 20.44 24.05 17.48 17.14 21.42 23.17 11.942 Al.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 4.030 MgO 0.00 0.00 0.00 0.97 0.54 0.51 1.039 CaO 13.37 7.43 13.94 15.89 8.63 8.10 16.285 Li.sub.2O 0.00 0.95 0.00 0.00 0.00 0.00 0.000 Na.sub.2O 6.00 17.14 2.51 0.00 10.99 10.31 0.000 K.sub.2O 0.00 0.95 0.00 0.00 0.00 0.00 0.000 ZnO 0.89 0.95 0.85 0.97 0.90 0.84 0.000 SrO 0.00 0.00 0.00 0.00 0.00 0.00 1.039 As.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.000 Y.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.000 Sb.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.000 La.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.000 Gd.sub.2O.sub.3 0.00 0.00 0.00 0.00 0.00 0.00 0.000 ZrO.sub.2 3.51 3.55 3.35 3.21 3.22 3.23 3.112 Total 100.00 100.00 100.00 100.00 100.00 100.00 100.00 Properties n.sub.d 1.994 1.897 1.981 1.984 1.953 1.963 1.980 v.sub.d 20.9 21.6 21.8 21.9 21.3 20.7 21.8 Density [g/cm.sup.3] 3.71 3.28 3.89 3.93 3.62 3.58 4.02

[0088] The glasses from the inventive examples have low density coupled with high refractive index and a favourable product of Abbe number and density, and have a low T.sub.max. In the context of the invention, it has been found that the glasses according to the invention have a low tendency to crystallization.

[0089] Although the present invention has been described with reference to preferred exemplary embodiments, it is not limited thereto, and is modifiable in various ways.