Optical glass, prefabricated member for mould pressing and optical element

Abstract

Provided is optical glass having a refractive index of higher than 1.88 and Abbe number of higher than 37, with high transmission and a low transition temperature, and suitable for precise moulding. The optical glass comprises SiO2 of more than 1% and less than 10% by weight; B2O3 of 10-20% by weight; La2O3 of 25-35% by weight; Gd2O3 of 10-20% by weight; Lu2O3 of more than 0% and less than 5% by weight, wherein La2O3 / (La2O3 + Gd2O3 + Lu2O3) is lower than 0.67; Ta2O of 10-20% by weight; ZnO of 8-15% by weight; LiO2 of 0.1-2% by weight; ZrO2 of 0.5-8% by weight; WO3 of 5-15% by weight; TiO2 of 0.1-3% by weight; and Sb2O3 of 0-0.2% by weight. For the optical glass with high refraction and low dispersion according to the present invention, by adjusting the content of La2O3, Gd2O3 and Lu2O3, the glass with a high index of refraction may be produced stably, which is suitable for precise moulding and can satisfy imaging requirements of optical systems and apparatuses.

Description

technical field [0001] The present invention relates to an optical glass, a preform for molding and an optical element, and more particularly, the present invention relates to a high-refractive and low-dispersion optical glass, a preform for molding formed from the glass, and a preform for molding formed from the glass. Optical element. Background technique [0002] High-refractive and low-dispersion optical glass is widely used in optical design, especially the optical glass with refractive index above 1.88 and Abbe number above 37. However, in general, the light transmittance of optical glass is closely related to the refractive index. The higher the refractive index, the worse the transmittance, and the more likely the glass tends to be colored. [0003] In addition, when precision press-molding glass elements, it is usually carried out in a high temperature environment, and problems such as oxidation and corrosion of the molding surface of the mold frequently occur, and...

AI Technical Summary

Problems solved by technology

However, the light transmittance of optical glass is usually closely related to the refractive index. The higher the refractive index, the lower the transmittance and the greater the coloring tendency of the glass.

[0003] In addition, when glass components are precision molded, they usually need to be carried out in a high-temperature environment, and problems such as oxidation and corrosion of the molding surface of the mold often occur, making it difficult to achieve low-cost mass production.

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