Precision optical glass for die pressing

Abstract

The invention provides optical glass which is applicable to low-cost precision molding aspheric lens, the components of which by weight percentage are 7-32 percent of SiO2, 13-40 percent of B2O3, 10-35 percent of La2O3, 1-8 percent of Y2O3, 5-25 percent of CaO, 3.5-9 percent of Li2O, 1-7 percent of ZrO2 and 0.002-0.05 percent of Sb2O3. The functional effect of the invention is that: Nd is from 1.63 to 1.695; Vd is from 52 to 58; molding temperature is lower than 600 DEG C; tinctorial strength is good; specific gravity is less than 3.50g / cm<3>; chemical stability is excellent; liquidus temperature is low, that is, anti-devitrification of the glass is good; in addition, the invention does not comprise the components of Pb, F, etc. which is harmful to environment and moulds, and is very suitable for precision optical elements with low cost and large volumes, such as molding aspheric lens, spherical lens, etc.

Description

technical field [0001] The invention relates to an optical glass with a refractive index (Nd) of 1.63-1.695 and an Abbe number (Vd) of 52-58. The molding temperature of the optical glass is lower than 600°C, and is suitable for low-cost precision molding aspherical lenses and other optical components. Background technique [0002] In recent years, various optoelectronic products such as digital cameras, digital video cameras and camera phones are increasingly pursuing miniaturization, high-performance and multi-functionality, so optical components such as lenses used in optical systems are also required to be miniaturized, lightweight and high-performance . Since the use of aspheric elements can eliminate spherical aberration and reduce the number of optical elements, the use of aspheric elements has become the mainstream in optical design. [0003] At present, the mainstream manufacturing method of small-diameter aspheric optical elements in the world is precision molding...

AI Technical Summary

Problems solved by technology

[0006] In addition, the optical glass used for aspheric lens, Nd is 1.63-1.695, Vd is 52-58, this type of glass is usually SiO 2 -B 2 o 3 -La 2 o 3 -RO (R stands for alkaline earth metal) system, and the transition temperature (Tg) of the glass is usually above 630°C, which is not suitable for precision molding

[0007] JP 5262533A discloses a SiO 2 -B 2 o 3 -La 2 o 3 -TiO 2 -CaO-BaO-Li 2 O system optical glass, but the system glass contains TiO 2 , Nb 2 o 5 , the color of the glass is darker, the transmittance is poor, and the glass transition temperature is relatively high, and the economy of precision molding is not good

[0008] JP 859282 discloses a B 2 o 3 -La 2 o 3 -ZnO-Li 2 The optical glass for molding of the O system, but from its examples, the sag temperature (Ts) of the glass is 590°C-630°C, the molding temperature is too high, and the production economy is not good

[0009] JP-1-286934 discloses a B 2 o 3 -SiO 2 -La 2 o 3 -CaO-Li 2 Optical glass for molding of O system, the glass softening temperature of this system is low, but the chemical stability of the glass is poor

[0010] CN998120677 provides a SiO 2 -B 2 o 3 -La 2 o 3 -Y 2 o 3 -Ta 2 o 5 -CaO-Li 2 The molded optical glass of the O system uses a certain amount of Ta in order to improve the crystallization performance of the glass. 2 o 5 , due to Ta 2 o 5 It is an expensive raw material, which will greatly increase the cost of glass and affect the competitiveness of products

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