Dense lanthanum flint glass

Abstract

The invention provides a dense lanthanum flint glass with a refractive index of 1.82-1.87 and an abbe number of 30-35. The glass has no apparent devitrification under the temperature of Tg+230 DEG C for over 30 minutes. The glass comprises, by mole percentage, LnO2(The LnO2 is one or more of SiO2, TiO2, ZrO2, Geo2 and CeO2), M2O3(The M2O3 is one or more of B2O3, La2O3, Y2O3, Yb2O3, Gd2O3, Ga2O3, Bi2O3, Al2O3 and Sb2O3), D2O5(The D2O5 is one or several substances of Nb2O5, Ta2O5 and P2O5) and RO. With a reasonable formula ratio design and on the precondition of guaranteeing the foreseeable optical property and performance, the flint glass is suitable for the production of high numerical aperture optical fibers and the glass elements which need heat treatment many times.

Description

technical field [0001] The present invention relates to a kind of high refraction glass, especially relates to a kind of flint glass whose refraction index is 1.82-1.87 and Abbe number is 30-35. Has excellent anti-devitrification properties. Background technique [0002] The glass with a refractive index of 1.82-1.87 and an Abbe number of 30-35 belongs to high refractive index lanthanum flint glass. Because of its high refractive index and low dispersion, it is widely used in various optical systems and is an important optical basis. Material. In the past, this type of glass was commonly used to make the elements in lenses. The current mainstream technology for making lenses is to use "secondary molding" to make lens blanks, and then polish them to obtain qualified glass lenses. The "secondary pressing" processing technology of optical glass refers to cutting the rough glass into small pieces, heating it in the furnace body to the softening temperature of the glass (gener...

AI Technical Summary

Problems solved by technology

If the anti-devitrification performance of the glass cannot meet the higher anti-devitrification requirements, it can only be made by cold working, which will greatly increase the manufacturing cost

In addition, the defective products of heavy lanthanum flint glass in the "secondary molding" can only be discarded as waste or remelted into glass again. The reason is that after the heavy lanthanum flint glass has undergone a "secondary molding" process, After another heating and pressing process, crystallization will occur on the surface and lead to scrapping, and the root cause is that the anti-crystallization performance of the glass is not enough to meet the needs of multiple heating and pressing.

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