Dense-lanthanum flint glass and prefabricated part thereof, optical element and optical instrument

Abstract

The invention discloses dense-lanthanum flint glass and a prefabricated part thereof, an optical element and an optical instrument. The dense-lanthanum flint glass contains, in percentage by weight, 12-30% of SiO2, 0-10% of B2O3, 10-25% of Ln2O3, 10.5-40% of TiO2+Nb2O5+WO3+Bi2O3, 18-40% of RO and 0.5-10% of ZrO2, wherein the percentage of the B2O3 is not 0, the content of the Ln2O3 is a sum of thecontents of La2O3, Gd2O3, Y2O3 and Yb2O3, the RO is one or more of BaO, CaO, MgO and SrO, and RO / B2O3 is larger than 0 and smaller than or equal to 70. A refraction index nd of the glass is 1.86-1.92, an abbe number is 25-30, the optical performance required for the precise instrument can be met, and the glass is excellent in thermal refractive index coefficient and good in water resistance effect stability and acid resistance effect stability.

Description

technical field [0001] The invention belongs to the field of optical glass, and in particular relates to heavy lanthanum flint glass and its prefabricated part, optical element and optical instrument. Background technique [0002] Heavy lanthanum flint glass with a refractive index (nd) of 1.86-1.92 and an Abbe number (vd) of 25-30 is widely used in lenses of precision optical instruments. These heavy lanthanum flint glasses can meet the requirements of modern precision molding processes. However, there are problems of high temperature coefficient of refractive index and poor chemical stability. [0003] On the one hand, the high temperature coefficient of refractive index restricts the popularization and application of heavy lanthanum flint glass in medical treatment, night photography, integrated circuit lithography and other fields. In optical instruments in these fields, the operating environment temperature of optical lenses continues to rise with the increase in use t...

AI Technical Summary

Problems solved by technology

In optical instruments in these fields, the operating environment temperature of optical lenses continues to rise with the increase in use time, and the refractive index of the glass also changes greatly, which seriously reduces the imaging quality of the glass and affects the system resolution.

Thermal aberration compensation technology needs to be used to make up for it, but these technologies have a high threshold and are only mastered by a few manufacturers in the world, and the application of heavy lanthanum flint glass is restricted

[0004] On the other hand, in order to reduce the high-temperature viscosity of the glass and improve the melting performance and mechanical properties of the glass, some metal oxide components are added to the existing heavy lanthanum flint glass. The distribution of metal cations in the glass grid structure affects the relationship between the glass and water molecules. Or the combination of hydrogen ions, so that the stability of the glass's water resistance and acid resistance will decrease

The requirements for the use environment of optical instruments are improved, and the maintenance cost is increased

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