Lead-free optical light flint glass materials
AssigneeSchott Glas
InventorsSilke Wolff, Peter Brix, Ute Woelfel
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Abstract
The lead-free optical light flint glass material has a refractive index nd between 1.54 and 1.61 and an Abbe number νd of between 38 and 45. It has a composition, based on oxide content, of SiO2 from 52 to 62% by weight, Al2O3 from 3 to 8% by weight, Na2O from 7 to 14% by weight, K2O from 8 to 14% by weight, TiO2 from 13 to 18% by weight, ZrO2 from 0 to 5% by weight, with at least one refining agent, if needed, in an amount suitable for the purposes of refining; and with the proviso that a sum total of Na2O and K2O present is greater than 18% by weight.
Claims8
A lead-free optical glass material with a refractive index nd of between 1.54 and 1.61 and an Abbe number νd of between 38 and 45, said glass material consisting, based on oxide content, of
- SiO2 from 52 to 62% by weight, Al2O3 from 3 to 8% by weight, Na2O from 7 to 14% by weight, K2O from 8 to 14% by weight, TiO2 from 13 to 18% by weight, ZrO2 from 0 to 5% by weight,
- and from 0.1 to 0.5% by weight of Sb2O3 as refining agent;
- and with the proviso that a sum total of said Na2O and said K2O present is greater than 18% by weight.
A lead-free optical glass material with a refractive index nd of between 1.55 and 1.60 and an Abbe number νd of between 39 and 44, said glass material consisting, based on oxide content, of
- SiO2 from 52 to 62% by weight, Al2O3 from 3 to 8% by weight, Na2O from 7 to 14% by weight, K2O from 8 to 14% by weight, TiO2 from 13 to 18% by weight, ZrO2 from 0 to 5% by weight,
- and from 0.1 to 0.5% by weight of Sb2O3 as refining agent;
- with the proviso that a sum total of said Na2O and said K2O present is greater than 18% by weight;
- and
- with the proviso that a sum total of said TiO2 and said ZrO2 present is not greater than 18% by weight.
A lead-free optical glass material with a refractive index nd of between 1.55 and 1.60 and an Abbe number νd of between 39 and 44, said glass material consisting, based on oxide content, of
- SiO2 from 52 to 62% by weight, Al2O3 from 3 to 8% by weight, Na2O from 7 to 14% by weight, K2O from 8 to 14% by weight, TiO2 from 13 to 18% by weight, ZrO2 from 0 to 5% by weight,
- and from 0.1 to 0.5% by weight of Sb2O3 and at least one fluoride in an amount of up to 5% by weight as refining agent;
- and
- with the proviso that a sum total of said Na2O and said K2O present is greater than 18% by weight.
A lead-free optical glass material with a refractive index nd of between 1.55 and 1.60 and an Abbe number νd of between 39 and 44, said glass material consisting, based on oxide content of
- SiO2 from 53 to 69% by weight, Al2O3 from 4 to 7% by weight, Na2O from 8 to 13% by weight, K2O from 10 to 14% by weight, TiO2 from 14 to 17% by weight,
- and at least one refining agent, if needed, in an amount suitable for the purposes of refining;
- and
- with the proviso that a sum total of said Na2O and said K2O present is greater than 18% by weight.
A lead-free optical glass material with a refractive index nd of between 1.56 and 1.59 and an Abbe number νd of between 39 and 44, said glass material consisting, based on oxide content, of
- SiO2 from 55 to 59% by weight, Al2O3 from 5 to 7% by weight, Na2O from 8 to 11% by weight, K2O from 10 to 12% by weight, TiO2 from 15 to 17% by weight,
- and at least one refining agent, if needed, in an amount suitable for the purposes of refining;
- and
- with the proviso that a sum total of said Na2O and said K2O present is greater than 18% by weight.
Dependencies are inferred from the claim text.