Environment-friendly low-melting-point optical glass

Abstract

The invention discloses environment-friendly low-melting-point optical glass, falling into the technical field of optical glass. It mainly solves such problems of existing optical glass that the existing optical glass contains environment-unfriendly components and has a high transition temperature Tg and a high softening temperature Tf. The optical glass contains the following components (by weight percentage and in terms of compounds): SiO2 17-36%, B2O3 18-38%, Li2O 5-12%, Sigma Na2O plus K2O 0-8%, La2O3 1-6%, Al2O3 0-1.5%, BaO 5-18%, SrO 0-5%, CaO 3-10%, ZnO 3-12%, TiO2 0-4%, and Sb2O3 0-1%, wherein each component percentage range covers the boundary values and the percentage sum of all the components is 100%. The invention has such optical characteristics that a refractive index nd falls into the range of 1.59-1.62, that a dispersion coefficient vd falls into the range of 53-39, that a transition temperature Tg is below 520 DEG C., and that a softening temperature Tf is below 580 DEG C., and is mainly used for spherical and aspherical precision-profiled environment-friendly low-melting-point optical glass.

Description

technical field [0001] The invention belongs to the technical field of optical glass. It specifically relates to an environment-friendly low-melting-point optical glass mainly used for precise pressing of spherical and aspherical surfaces. Background technique [0002] Low melting point glass refers to glass with relatively low transition temperature (Tg), which is mainly used for precision molding of spherical and aspherical surfaces, which is beneficial to reduce the molding temperature and prolong the service life of the mold. The transition temperature (Tg) of the existing glass of this type is generally above 550°C, which will make the glass have a higher softening temperature (Tf) and molding temperature, and a higher molding temperature will make the mold easy to be oxidized and Damage the surface of the pressing mold, reduce the life cycle of the mold, thereby increasing the cost of the pressing, and the glass with a higher softening temperature (Tf) is not suitable...

AI Technical Summary

Problems solved by technology

[0007] The glass disclosed in the patent CN1817809A belongs to the same type of glass as the present invention, but it is quite different from the present invention in terms of composition. It is different from the protection range of 17% to 36% in the present invention, and its SiO content is greater than 37%. 2 It will increase the difficulty of smelting glass. During smelting, lumps that are not easy to melt are more likely to appear on the wall of the crucible, making the components entering the glass unstable, thus affecting the stability of the product.

In addition, the BaO greater than 24% in CN1817809A is also different from the protection scope of the present invention, too much BaO will make the glass-forming area that can meet the given optical property smaller

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