Optical glass, optical prefabticated member and optical element

Abstract

The invention provides optical glass with excellent anti-devitrification performance, chemical stability and hardness. The optimal glass is prepared from the following ingredients in a cationic mole percent: 30-50% of P<5+>, 5-25% of Al<3+>, 15-30% of Ba<2+>, 0-20% of Sr<2+>, 0-10% of Gd<3+>, 0-10% of Y<3+> and 0-10% of La<3+>, wherein (Gd<3+>+ La<3+>)/Ln<3+> is equal to 0.1-0.8; anions contain F<->and O<2->, wherein the molar ratio F<->/(F<->+O<2->) of the content of F<-> to the total amount of F<->and O<2-> is equal to 0.3-0.5. According to the optical glass, a ratio of all components is reasonably regulated, so that the fluorophosphates optical glass has excellent anti-devitrification performance, chemical stability and hardness while the fluorophosphate optical glass has the refractiveindex of 1.54-1.61 and the Abbe number of 69-76.

Description

technical field [0001] The invention relates to an optical glass, in particular to an optical glass with a refractive index of 1.54-1.61 and an Abbe number of 69-76, and an optical preform and an optical element formed from the optical glass. Background technique [0002] In optical systems such as cameras, in order to eliminate the chromatic aberration of the lens, the "achromatic" design of combining glasses with different Abbe numbers is usually adopted, so it is necessary to combine optical glasses with different refractive indices and Abbe numbers to form a reasonable optical system . As a new type of glass material widely used, fluorophosphate optical glass has the characteristics of low dispersion. In the optical system, it can eliminate the special dispersion of the secondary spectrum, improve the resolution, and significantly improve the imaging quality of the optical system. At the same time, it also has low softening. temperature, it can be directly precision mol...

AI Technical Summary

Problems solved by technology

However, the current fluorophosphate optical glass with a refractive index of 1.54-1.61 and an Abbe number of 69-76 usually has poor crystallization resistance, and is easy to crystallize during production and precision molding, which reduces the yield of glass.

Images