Optical glass

Abstract

The invention provides optical glass with high refraction power and low chromatic dispersion. The optical glass comprises, by weight, 1 to 30% of B2O3, 0.1 to 15% of SiO2, 25 to 52% of La2O3, 1 to 30% of Gd2O3, more than 0 and no more than 12% of Y2O3, 1 to 10% of ZrO2, 1 to 30% of Nb2O5, 0 to 10% of Ta2O5, 0 to 5% of TiO2, 0 to 5% of WO3, 0 to 10% of ZnO, 0 to 10% of Al2O3 and 0 to 10% of GeO2. The glass does not contain PbO and F and has a refractive index in a range of 1.86 to 1.92 and an Abbe number in a range of 37 to 42. The environment-friendly optical glass with excellent transmittance, high refraction power and low chromatic dispersion is obtained by introducing a proper amount of rare earth oxide components with high refraction power and low chromatic dispersion.

Description

technical field [0001] The invention relates to an optical glass with high refractive index and low dispersion characteristics, as well as a glass preform and an optical element formed from the optical glass. Background technique [0002] Combining lenses made of high refractive index and low dispersion optical glass with lenses made of high refractive index and high dispersion optical glass can correct chromatic aberration and miniaturize the optical system, especially when the refractive index nd is 1.86-1.92 and the Abbe number νd is 36-42 environmental protection optical glass with high refractive index and low dispersion, the market demand is increasing day by day. [0003] Japanese Patent Application No. 2001-348244, Patent Application No. 2007-269584, and Chinese CN101386469A all disclose this type of high-refraction and low-dispersion optical glass. In the examples of the description, optical glass components with a refractive index of 1.86 or more contain a large am...

AI Technical Summary

Problems solved by technology

At the same time, the optical elements of optical systems such as camera or projection have high requirements on the transmittance of optical glass. If the amount of transmitted light through the lens formed by high-refraction and low-dispersion optical glass is insufficient, the amount of transmitted light of the optical system will be greatly reduced or dropped sharply. Therefore, It is hoped that the optical glass has excellent transmittance performance; in addition, if F is contained in the glass, the volatility of the glass melt will increase, and texture will be generated when the glass melt is formed, and the refractive index of the glass will increase due to the volatilization of F.

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