Heavy lanthanum flint glass and its preforms, optical components and optical instruments

Abstract

The invention discloses a heavy lanthanum flint glass and its prefabricated piece, optical element and optical instrument. The heavy lanthanum flint glass contains by weight %: SiO 2 : 12‑30%, B 2 o 3 : 0‑10% and not 0, Ln 2 o 3 : 10‑25% of the Ln 2 o 3 for la 2 o 3 、Gd 2 o 3 , Y 2 o 3 and Yb 2 o 3 The total content of TiO 2 +Nb 2 o 5 +WO 3 +Bi 2 o 3 : 10.5‑40%, RO: 18‑40%, the RO is one or more of BaO, CaO, MgO and SrO, ZrO 2 : 0.5‑10%, where RO / B 2 o 3 Greater than 0 and less than or equal to 70. The glass has a refractive index nd of 1.86-1.92 and an Abbe number vd of 25-30, which can meet the optical properties required by precision instruments, and has an excellent temperature coefficient of refractive index, good stability in water resistance and acid resistance.

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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