Headlight lens for a motor vehicle
View Patent ↗The invention relates to a headlight lens for a vehicle headlight comprising a light source, particularly for a motor vehicle headlight, wherein the headlight lens comprises a transparent lens body made of glass comprising a surface arranged to face the light source and a surface arranged to face away from the light source, and wherein the headlight lens comprises at least with respect to said surface arranged to face away from the light source a layer comprising an aluminum concentration which is higher than an aluminum concentration inside the lens body and/or a sodium concentration which is lower than a sodium concentration inside the lens body.
1. Vehicle headlight lens for imaging an edge of a shield as a brightness-darkness-boundary, the vehicle headlight lens comprising:
a transparent lens body made of glass, the transparent lens body including:
a substantially plane surface; and
a convexly curved surface, wherein the convexly curved surface includes one of the group of
a layer comprising an aluminum concentration which is higher than an aluminum concentration inside the lens body; and
a layer comprising a sodium concentration which is lower than a sodium concentration inside the lens body.
2. Vehicle headlight lens according to claim 1 , the vehicle headlight lens being blank molded.
3. Vehicle headlight lens according to claim 1 , wherein the glass comprises Na 2 O.
4. Vehicle headlight lens according to claim 3 , the glass comprises 2 to 15 weight-% Na 2 O.
5. Vehicle headlight lens according to claim 3 , wherein the glass comprises
50 to 75 weight-% SiO 2 ,
2 to 15 weight-% Na 2 O,
5 to 15 weight-% K 2 O,
3 to 12 weight-% CaO,
0 to 10 weight-% B 2 O 3 ,
0 to 5 weight-% Al 2 O 3 ,
0 to 5 weight-% Li 2 O,
0 to 5 weight-% MgO,
0 to 7 weight-% SrO,
0 to 7 weight-% ZnO,
0 to 8 weight-% TiO 2 ,
0 to 5 weight-% ZrO 2 ,
0.1 to 5 weight-% Nb 2 O 5 ,
0 to 5 weight-% Ta 2 O 5 , and
0 to 2 weight-% F.
6. Vehicle headlight lens according to claim 5 , wherein the glass comprises 13 to 16 weight-% Na 2 O.
7. Vehicle headlight lens according to claim 3 , wherein the glass comprises 13 to 16 weight-% Na 2 O.
8. Vehicle headlight lens according to claim 3 , wherein the glass comprises about
71 to 73 weight-% SiO 2 ,
13 to 16 weight-% Na 2 O,
0 to 1 weight-% K 2 O,
6.5 to 12 weight-% CaO,
0 to 1.8 weight-% Al 2 O 3 , and
2 to 4.5 weight-% MgO.
9. Vehicle headlight comprising:
a light source; and
a vehicle headlight lens for imaging an edge of a shield located between the light source and the vehicle headlight lens as a brightness-darkness-boundary, the vehicle headlight lens comprising:
a transparent lens body made of glass, the transparent lens body including:
a surface facing the light source; and
a surface facing away from the light source and including one of the group of a layer comprising an aluminum concentration which is higher than an aluminum concentration inside the lens body; and
a layer comprising a sodium concentration which is lower than a sodium concentration inside the lens body.
10. Vehicle headlight according to claim 9 , the vehicle headlight lens being blank molded.
11. Vehicle headlight according to claim 9 , wherein the glass comprises Na 2 O.
12. Vehicle headlight according to claim 11 , the glass comprises 2 to 15 weight-% Na 2 O.
13. Vehicle headlight according to claim 11 , wherein the glass comprises
50 to 75 weight-% SiO 2 ,
2 to 15 weight-% Na 2 O,
5 to 15 weight-% K 2 O,
3 to 12 weight-% CaO,
0 to 10 weight-% B 2 O 3 ,
0 to 5 weight-% Al 2 O 3 ,
0 to 5 weight-% Li 2 O,
0 to 5 weight-% MgO,
0 to 7 weight-% SrO,
0 to 7 weight-% ZnO,
0 to 8 weight-% TiO 2 ,
0 to 5 weight-% ZrO 2 ,
0.1 to 5 weight-% Nb 2 O 5 ,
0 to 5 weight-% Ta 2 O 5 , and
0 to 2 weight-% F.
14. Vehicle headlight according to claim 9 , wherein the glass comprises 13 to 16 weight-% Na 2 O.
15. Vehicle headlight according to claim 11 , wherein the glass comprises 13 to 16 weight-% Na 2 O.
16. Vehicle headlight according to claim 11 , wherein the glass comprises about
71 to 73 weight-% SiO 2 ,
13 to 16 weight-% Na 2 O,
0 to 1 weight-% K 2 O,
6.5 to 12 weight-% CaO,
0 to 1.8 weight-% Al 2 O 3 , and
2 to 4.5 weight-% MgO.
17. Vehicle headlight lens for imaging an edge of a shield as a brightness-darkness-boundary, the vehicle headlight lens comprising:
a transparent lens body made of glass, the transparent lens body including:
a surface arranged to face the light source; and
a surface arranged to face away from the light source and including one of the group of
a layer comprising an aluminum concentration which is higher than an aluminum concentration inside the lens body; and
a layer comprising a sodium concentration which is lower than a sodium concentration inside the lens body.
18. Vehicle headlight lens according to claim 17 , the vehicle headlight lens being blank molded.
19. Vehicle headlight lens according to claim 17 , wherein the glass comprises Na 2 O.
20. Vehicle headlight lens according to claim 17 , the glass comprises 2 to 15 weight-% Na 2 O.
21. Vehicle headlight lens according to claim 17 , wherein the glass comprises
50 to 75 weight-% SiO 2 ,
2 to 15 weight-% Na 2 O,
5 to 15 weight-% K 2 O,
3 to 12 weight-% CaO,
0 to 10 weight-% B 2 O 3 ,
0 to 5 weight-% Al 2 O 3 ,
0 to 5 weight-% Li 2 O,
0 to 5 weight-% MgO,
0 to 7 weight-% SrO,
0 to 7 weight-% ZnO,
0 to 8 weight-% TiO 2 ,
0 to 5 weight-% ZrO 2 ,
0.1 to 5 weight-% Nb 2 O 5 ,
0 to 5 weight-% Ta 2 O 5 , and
0 to 2 weight-% F.
22. Vehicle headlight lens according to claim 17 , wherein the glass comprises about
71 to 73 weight-% SiO 2 ,
13 to 16 weight-% Na 2 O,
0 to 1 weight-% K 2 O,
6.5 to 12 weight-% CaO,
0 to 1.8 weight-% Al 2 O 3 , and
2 to 4.5 weight-% MgO.
23. Method of producing a vehicle headlight lens for imaging an edge of a shield as a brightness-darkness-boundary; the method comprising the steps of:
blank molding the headlight lens consisting essentially of glass; and
subsequently cooling the headlight lens;
overflowing the headlight lens during the cooling process with a gas containing at least one of the group of sulphur, chlorine, fluorine, iron and aluminum.
24. Method according to claim 23 , wherein the gas comprises at least one of the group of HCl, CF 4 and AlCl 3 .
25. Method according to claim 23 , wherein the gas is sucked off.