Heavy Lanthanum Flint Optical Glass with High Refractive Index and Low Dispersion

Abstract

The invention relates to a high-refractive index and low-dispersion heavy lanthanum flint optical glass which is prepared from the following components in percentage by mass of oxides: 9.25-13.37 percent of B2O3, 5.48-7.34 percent of SiO2, 43.60-51.63 percent of La2O3, 3.53-9.12 percent of Y2O3, 4.18-10.23 percent of Gd2O3, 3.47-6.52 percent of Nb2O5, 3.47-6.62 percent of ZrO2, 0.81-1.50 percent of WO3, 3.96-6.95 percent of TiO2, 3.28-6.79 percent of ZnO and 0.61-1.52 percent of Al2O3; and in the composition, the following conditions are also met: B / Si is larger than 1.33 and smaller than 2.54 (by mass percentage), a sum of the mass percentages of La2O3, Y2O3 and Gd2O3 is 58.61-60.32 percent, and a sum of the mass percentages of WO3 and TiO2 is 4.85-8.34 percent. The optical glass does not contain Ta2O3 with high cost to facilitate reduction of the cost of the glass, does not contain alkali metals, alkaline-earth metals and toxic components including Pb, As and Cd either, has the refractive index nd being 1.883-1.915 and an abbe number vd being 35.65-38.32, is excellent in crystallization resistance and is suitable for batch production.

Description

technical field [0001] The present invention relates to optical glass, especially a kind of heavy lanthanum flint optical glass with high refractive index and low dispersion, its refractive index n d 1.883~1.915, Abbe number ν d It is 35.65~38.32. Background technique [0002] Rare-earth optical glass has the characteristics of high refractive index and low dispersion, and is an indispensable optical material for the manufacture of large-aperture, wide-field photographic objectives, long focal length, zoom lenses, and high-power microscope lenses. It is of great significance for improving the imaging quality and simplifying the design of optical instruments, especially photographic objectives, and is currently widely used in high-altitude photography, telescopes, periscopes, movies, microscopes, and advanced cameras. [0003] In recent years, with the development of digital camera, video camera and mobile phone technology, the requirements for supporting lenses are getting...

AI Technical Summary

Problems solved by technology

[0005] Chinese patent application CN104692653A discloses a high refractive index and high dispersion optical glass with a refractive index of 1.93-1.99 and an Abbe number of 27-38, which does not meet the conditions of high refractive index and low dispersion

[0006] Chinese patent application CN101337768A discloses a high refractive index optical glass with a refractive index of 1.86-1.92 and an Abbe number of 35-40, which contains 6-20% Ta 2 o 3 , due to Ta 2 o 3 Expensive, not conducive to the reduction of glass cost

[0007] Chinese patent application CN102674691A discloses a high-refractive-index low-dispersion optical glass with a refractive index of 1.90-1.92 and an Abbe number of 33-36, which contains 8-14% by mass of Y 2 o 3 , with a mass percentage of 7-13% Nb 2 o 5 , so that the glass is easy to crystallize, which is not conducive to mass production