Optical glass

Abstract

The invention provides optical glass taking SiO2, Nb2O5, BaO and La2O3 as main components of the optical glass without lead, thorium, cadmium, arsenic and fluorine. The refractive index (nd) of the optical glass is between 1.78 and 1.82, and the abbe number (vd) is between 27 and 32. The optical glass has the characteristics of being good in pigmentation degree and crystal separation performance and suitable for production. The optical glass comprises the following compounds by weight percentage: 19% to 25% of SiO2, 5% to 10% of B2O3, 4% to 9% of La2O3, 19% to 27% of Nb2O5, 4% to 10% of Na2O, 0% to 3% of Li2O, 2% to 6% of CaO, 10% to 15% of BaO, 0% to 4% of SrO, 5% to 10% of TiO2, 4% to 8% of ZrO2, 3% to 8% of WO3 and 0% to 1% of Sb2O3, wherein the total content of the oxides accounts for more than 99%.

Description

technical field [0001] The invention relates to an optical glass, in particular to a heavy lanthanum flint optical glass with a refractive index (nd) between 1.78-1.82 and an Abbe number (vd) between 27-32. Background technique [0002] In recent years, in order to meet the high-pixel, small and light requirements of high-end digital products, the demand for heavy lanthanum flint optical glass with the advantages of high refraction, medium dispersion, and small specific gravity is increasing. In order to make the glass have the above properties, the La in the glass 2 o 3 、TiO 2 , Nb 2 o 5 The component content is also gradually increasing, but too much of these components will lead to defects such as low glass viscosity, difficult molding, difficulty in obtaining high-quality streaks, and severe crystallization. At the same time, traditional lanthanide optical glass components generally contain elements such as lead, arsenic, and cadmium, because lead oxide can improve ...

AI Technical Summary

Problems solved by technology

In addition, the gradual introduction of ZnO will gradually deteriorate the chemical stability of the glass, which is not conducive to the realization of the present invention. A 、D W All level 1 targets

Meanwhile, from the embodiment of patent application CN1807305A, its SiO 2 The content is below 10%, and less SiO is used in the glass system 2 Can make the chemical stability of glass worse, be unfavorable for realizing the present invention D A 、D W All level 1 targets

[0009] The glass disclosed in the patent application CN101012103A partially overlaps with the scope of protection of the present invention, but emphasizes B in its components 2 o 3 content>SiO 2 content, also contains more than 10% La 2 o 3 Components are quite different from the implementation and protection scope of the present invention. In addition, for chemical stability, SiO 2 The introduction ratio of B 2 o 3 More favorable, i.e. emphasis on B 2 o 3 content>SiO 2 The content is not conducive to the realization of the present invention D A 、D W All are Level 1 targets, and more La 2 o 3 It will lead to defects such as low glass viscosity, high molding difficulty, difficulty in obtaining high-quality streaks, and severe crystallization.

[0010] Patent CN1308252C is similar to patent application CN101012103A, and the glass it discloses also partially overlaps with the scope of protection of the present invention, but its components emphasize B 2 o 3 content>SiO 2 content, also contains more than 10% La 2 o 3 Components are quite different from the implementation and protection scope of the present invention. In addition, for chemical stability, SiO 2 The introduction ratio of B 2 o 3 More favorable, i.e. emphasis on B 2 o 3 content>SiO 2 The content is not conducive to the realization of the present invention D A 、D W All are Level 1 targets, and more La 2 o 3 It will lead to defects such as low glass viscosity, high molding difficulty, difficulty in obtaining high-quality streaks, and severe crystallization.

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