Nb-containing optical glass, method for producing the same, and use thereof

Abstract

The application provides a kind of Nb-containing optical glass and its preparation method and application, by introducing R metal, M metal and trace modification components into raw material components, the melting temperature is reduced, the erosion of crucible is reduced, and the formability and stability are improved;The preparation method adopts raw material mixing, pre-smelting, secondary melting, clarification-homogenization, forming and annealing process, introduces composite clarifying oxidant, uses non-coloring high-temperature resistant crucible for pre-smelting, uses zirconium reinforced platinum crucible for secondary melting, and controls halogen-containing gas, inert gas, oxidation atmosphere to inhibit coloring in sections.The application realizes high refractive index and high visible light transmission by optimizing components, crucible, atmosphere and process, the glass has few defects, stable performance, suitable for mass production, and can be widely used in smart phones, AR / VR glasses, single-lens reflex cameras, high-end microscopes, high-definition / ultra-high-definition (4K / 8K) monitoring, vehicle-mounted and high-end imaging systems, etc.

Description

Technical Field

[0001] This invention relates to the field of optical glass, especially high refractive index optical glass, and more specifically, to an Nb-containing optical glass, its preparation method, and its applications. Background Technology

[0002] In recent years, with the rapid development of optoelectronic products such as smartphones, SLR cameras, and security surveillance systems, higher requirements have been placed on optical clarity and field of view, leading to the increasingly widespread application of high-refractive-index glass. In optical design, high-refractive-index optical glass is required to have higher transmittance.

[0003] However, current high-refractive-index glasses still have the following problems: (1) Because high-refractive-index glasses usually contain a high content of Nb2O5, TiO2 and other components, Nb 5+ Ti 4+ (1) It is easily reduced to a low valence state, which leads to glass coloring and reduces glass transmittance, especially in the blue light region; (2) The high rare earth and high Nb system has a high melting temperature, which seriously corrodes the crucible; (3) Ordinary crucibles have low purity, large roughness and insufficient density, which easily introduce impurities and cause glass coloring and defects.

[0004] Furthermore, traditional optical glass manufacturing methods struggle to simultaneously achieve both high refractive index and high transmittance. Existing phosphate-based glass manufacturing methods also suffer from drawbacks such as high production difficulty, high raw material costs, significant corrosion and consumption of platinum-plated equipment used in the production process, and substantial environmental impact.

[0005] Therefore, developing an optical glass with both high transmittance and high refractive index, and good overall performance, has become an urgent problem to be solved in this field. In particular, in the visible light band, how to prepare high refractive index glass with high transmittance in the visible light band is of great significance for improving the overall performance and application range of optical systems.

[0006] In view of this, the present invention is hereby proposed. Summary of the Invention

[0007] The purpose of this invention is to address the shortcomings of existing glass, such as low visible light transmittance, easy coloring, and severe crucible erosion. It provides a high-transmittance Nb-containing optical glass in the visible light band, its preparation method, and its applications. This invention solves the problems of low transmittance and insufficiently optimized component ratios in existing high-refractive-index glasses. By matching the raw material components with the preparation process and synergistically optimizing the components, crucible, atmosphere, and process, Nb-containing optical glasses with excellent transmittance and chemical stability are obtained. This achieves a balance between high refractive index and high visible light transmittance, with fewer glass defects, stable performance, and suitability for mass production.

[0008] In order to achieve the above-mentioned objectives of the present invention, the following technical solution is adopted: A method for preparing Nb-containing optical glass includes the following steps: Step S1, Raw material mixing: Weigh the raw materials according to the component ratio of Nb-containing optical glass, and mix them evenly to obtain a mixture; Step S2, Pre-melting: Inert protective gas or oxygen is introduced into the mixture for pre-melting to obtain glass slag; Step S3, Secondary Melting: The glass slag is melted and stirred a second time to obtain molten glass; Step S4, Clarification-Homogeneity: A mixture of inert protective gas and oxidizing gas is introduced into the molten glass to perform clarification-homogenization; Step S5, Forming: The clarified and homogenized molten glass is injected into the mold for forming. During the forming process, a mixture of inert protective gas and oxidizing gas is introduced. Step S6, Annealing: Anneal the formed glass to obtain Nb-containing optical glass products.

[0009] Further, the composition ratio of the Nb-containing optical glass in step S1, by weight percentage, includes the following oxide components: B2O3+SiO2+P2O5: 4-40%, Nb2O5: 3-52%, RE2O3: 0-70%, R2O: 0-10%, MO: 0-30%, ZrO2: 0-8%, TiO2+WO3: 0-43%, Ta2O5: 0-20%; wherein, the contents of B2O3, SiO2, and P2O5 in B2O3+SiO2+P2O5 can all be 0%, but the three cannot be 0% at the same time; RE is at least one of La, Y, Gd, and Yb; R is at least one of Li, Na, and K; and M is at least one of Mg, Ca, Sr, Ba, and Zn.

[0010] Furthermore, the R2O includes at least 0.2-1.0% Li2O.

[0011] Furthermore, the raw materials mentioned in step S1 also include a composite clarifying agent-oxidizing agent, which comprises, by weight percentage, the following components: Sb2O3: 0.001-0.02%, SO3: 0.002-0.6%, SnO2: 0.00-1.0%, CeO2: 0.00-1.0%, and CoO: 0.00-2.0%.

[0012] Further, in step S2, the mixture is put into a quartz crucible, a corundum crucible, or a zirconium crucible for pre-melting.

[0013] Furthermore, in step S2, the pre-melting temperature is 1150-1350℃, and the time is 5-20h.

[0014] Furthermore, in step S2, the flow rate of the inert protective gas or oxygen introduced during the pre-melting process is 0.2-5 L / min.

[0015] Furthermore, during the preparation of Nb-containing phosphate optical glass, an inert protective gas is introduced during the pre-melting process.

[0016] Furthermore, oxygen is introduced during the pre-melting process when preparing Nb-containing borosilicate optical glass.

[0017] Furthermore, in steps S3 and S4, the glass slag is added to a precious metal crucible for secondary melting, stirring, clarification, and homogenization.

[0018] Furthermore, in step S3, the secondary melting temperature is 1200-1360℃, and the melting time is 3-10h.

[0019] Furthermore, in step S3, the stirring speed is 20-60 rpm and the stirring time is 2-10 h.

[0020] Furthermore, in step S3, during the secondary melting and stirring process, a mixture of halogen-containing gas and inert protective gas is introduced, wherein the flow rate of the halogen-containing gas is 0.1-0.3 L / min and the flow rate of the inert protective gas is 1-3 L / min.

[0021] Furthermore, in step S3, halides are added to the glass slag during the secondary melting process, and an inert protective gas is introduced during the secondary melting and stirring process, with an inert protective gas flow rate of 1-3 L / min.

[0022] Furthermore, the halogen-containing gas is at least one of Cl2, CCl4, and CF4.

[0023] Furthermore, the halide is at least one of KF, LiF, and NaCl.

[0024] Furthermore, the amount of halide added accounts for 0.3-2% of the mass of the glass slag.

[0025] Furthermore, in step S4, during the clarification-homogenization process, a mixture of inert protective gas and oxidizing gas is introduced, wherein the flow rate of the inert protective gas is 0.2-0.7 L / min and the flow rate of the oxidizing gas is 0.5-1.7 L / min.

[0026] Furthermore, in step S5, the preheating temperature of the mold before molding is 300-700℃, and the molding temperature is 1100-1350℃.

[0027] Furthermore, in step S5, the molten glass is poured or cast into a mold to form the shape.

[0028] Furthermore, during the molding process in step S5, a mixture of inert protective gas and oxidizing gas is introduced, wherein the flow rate of the inert protective gas is 0.2-0.7 L / min and the flow rate of the oxidizing gas is 0.5-1.7 L / min.

[0029] Furthermore, the annealing in step S6 is fine annealing.

[0030] Furthermore, in step S6, the annealing temperature is 500-700℃, and the annealing time is 4-100h.

[0031] The Nb-containing optical glass prepared by the above preparation method is either Nb-containing phosphate optical glass or Nb-containing borosilicate optical glass. The composition of the Nb-containing phosphate optical glass, by weight percentage, includes the following oxide components: P2O5: 10-30%, SiO2: 0%-3%, B2O3: 0-6%, Nb2O5: 20-52%, R2O: 0-10%, MO: 0-30%, ZrO2: 0-2%, TiO2: 10-20%, WO3: 0-10%; wherein R is at least one of Li, Na, and K; and M is at least one of Mg, Ca, Sr, Ba, and Zn. The composition of the Nb-containing borosilicate optical glass, by weight percentage, includes the following oxide components: B2O3: 1%-20%, SiO2: 3%-20%, Nb2O5: 3-30%, RE2O3: 0-70%, R2O: 0-10%, MO: 0-30%, ZrO2: 0-8%, TiO2: 1-33%, WO3: 0-10%; wherein RE is at least one of La, Y, Gd, and Yb; R is at least one of Li, Na, and K; and M is at least one of Mg, Ca, Sr, Ba, and Zn.

[0032] The lens is made of the aforementioned Nb-containing optical glass.

[0033] The above-mentioned Nb-containing optical glass or lenses are used in the manufacture of smartphones, AR / VR glasses, SLR cameras, high-end microscopes, high-definition / ultra-high-definition surveillance, automotive and high-end imaging systems.

[0034] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention optimizes the component ratio of Nb-containing optical glass, especially by using a scientific ratio of multiple components such as B2O3, SiO2, P2O5, Nb2O5, RE2O3, R2O, MO, ZrO2, TiO2, and WO3, and introduces a composite clarifying agent-oxidant, thereby achieving the dual performance of high transmittance and high refractive index of the glass. This effectively solves the problem that traditional optical glass cannot simultaneously achieve both high refractive index and high transmittance.

[0035] 2. This invention employs a staged melting process, using a crucible without coloring elements for pre-melting, followed by subsequent processing with a precious metal crucible with strong corrosion resistance. During glass preparation, halogen-containing gases, inert protective gases, and oxidizing gases are introduced, with different types and flow rates of each gas at different stages. By rationally controlling the atmosphere, the corrosion of the crucible by the glass products is effectively reduced, the glass transmittance is improved, the production cycle is extended, and the production cost is reduced.

[0036] 3. By precisely controlling process parameters such as melting temperature, stirring speed and time, forming temperature and annealing temperature, this invention ensures the quality stability and performance consistency of glass products, and solves the problem of unstable glass performance in the prior art.

[0037] 4. The Nb-containing optical glass prepared by this invention exhibits excellent transmittance, achieving an internal transmittance of over 92.5% (Nb-containing phosphate optical glass) and over 95% (Nb-containing borosilicate optical glass) in the visible light band, particularly at 460 nm. The Nb-containing optical glass of this invention is divided into phosphate and borosilicate systems. The phosphate system is mainly composed of P₂O₅, Nb₂O₅, and TiO₂, with a refractive index n. d ≥1.92, transmittance within 460nm ≥92.5%; borosilicates are mainly composed of B2O3, SiO2, Nb2O5 and rare earth oxides, with a refractive index n d With a transmittance of ≥1.90 and ≥95% within 460nm, it meets the growing demand for high transmittance and significantly improves the overall performance of the optical system.

[0038] 5. This invention achieves a balance between high refractive index and high visible light transmittance through synergistic optimization of components, crucible, atmosphere, and process. The resulting glass exhibits fewer defects, stable performance, and suitability for mass production. The Nb-containing optical glass of this invention can be widely used in smartphones, AR / VR glasses, SLR cameras, high-end microscopes, high-definition / ultra-high-definition surveillance, automotive applications, and high-end imaging systems, demonstrating significant practical value and application prospects. Attached Figure Description

[0039] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0040] Figure 1The image shows a comparison of the Nb-containing phosphate optical glass before and after the improvement in transmittance (the left side is the Nb-containing phosphate optical glass prepared in Comparative Example 1, and the right side is the Nb-containing phosphate optical glass prepared in Example 5). Figure 2 This is a photo comparison of the Nb-containing borosilicate optical glass before and after the improvement in transmittance of the present invention (the left side is the Nb-containing borosilicate optical glass prepared in Comparative Example 10, and the right side is the Nb-containing borosilicate optical glass prepared in Example 10). Detailed Implementation

[0041] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. However, those skilled in the art will understand that the embodiments described below are some embodiments of the present invention, but not all embodiments, and are only used to illustrate the present invention, and should not be regarded as limiting the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall be followed. Where the manufacturers of reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0042] A method for preparing Nb-containing optical glass includes the following steps: Step S1, Raw material mixing: Weigh the raw materials according to the component ratio of Nb-containing optical glass, and mix them evenly to obtain a mixture; Step S2, Pre-melting: Inert protective gas or oxygen is introduced into the mixture for pre-melting to obtain glass slag; Step S3, Secondary Melting: The glass slag is melted and stirred a second time to obtain molten glass; Step S4, Clarification-Homogeneity: A mixture of inert protective gas and oxidizing gas is introduced into the molten glass to perform clarification-homogenization; Step S5, Forming: The clarified and homogenized molten glass is injected into the mold for forming. During the forming process, a mixture of inert protective gas and oxidizing gas is introduced. Step S6, Annealing: Anneal the formed glass to obtain Nb-containing optical glass products.

[0043] In some embodiments, the composition ratio of the Nb-containing optical glass in step S1, by weight percentage, includes the following oxide components: B2O3+SiO2+P2O5: 4-40%, Nb2O5: 3-52%, RE2O3: 0-70%, R2O: 0-10%, MO: 0-30%, ZrO2: 0-8%, TiO2+WO3: 0-43%, Ta2O5: 0-20%; wherein, the contents of B2O3, SiO2, and P2O5 in B2O3+SiO2+P2O5 can all be 0%, but the three cannot be 0% at the same time; RE is at least one of La, Y, Gd, and Yb; R is at least one of Li, Na, and K; and M is at least one of Mg, Ca, Sr, Ba, and Zn.

[0044] In some implementations, R2O includes at least 0.2-1.0% Li2O. The addition of trace amounts of Li2O reduces the melting temperature, decreases crucible erosion, and further optimizes the smelting process.

[0045] This invention introduces Li₂O, which significantly reduces the melting temperature and high-temperature viscosity of the glass batch, widening the glass melting temperature range and enabling the glass to melt, clarify, and homogenize at lower temperatures. Since the interfacial reaction rate between the molten glass and the platinum crucible, as well as the dissolution and diffusion rate of platinum, both increase exponentially with increasing temperature, lowering the melting temperature effectively slows down the chemical erosion and high-temperature dissolution of the platinum crucible by the molten glass, reducing platinum ion (Pt) concentrations. 4+ Pt 2+ The platinum ions dissolve into the glass matrix, thereby suppressing the weak absorption and coloration in the visible light band caused by platinum ions, while reducing light scattering caused by platinum particles, and ultimately significantly improving the internal transmittance of the glass in the visible light, especially in the short-wavelength region.

[0046] In some embodiments, the raw materials in step S1 further include a composite clarifying agent-oxidizing agent, which comprises, by weight percentage, the following components: Sb2O3: 0.001-0.02%, SO3: 0.002-0.6%, SnO2: 0.00-1.0%, CeO2: 0.00-1.0%, CoO: 0.00-2.0%.

[0047] This invention introduces a composite clarifying agent-oxidant consisting of Sb₂O₃, SO₃, SnO₂, CeO₂, and CoO. The components work synergistically to achieve glass decolorization and improved transmittance. Specifically, Sb₂O₃ undergoes Sb oxidation at high temperatures. 3+ / Sb 5+Valence state transformation can both act as a clarifying agent to remove bubbles and increase the valence of variable-valence ions such as Ti, Nb, and Fe, thereby reducing their visible light absorption; SO3 provides a strong oxidizing atmosphere, promoting the oxidation of low-valence coloring ions to colorless or weakly absorbing valence states, while simultaneously reducing the surface tension of the molten glass, enhancing bubble removal, and reducing transmission loss caused by bubbles and scattering; SnO2, through Sn 2+ / Sn 4+ The variable valence equilibrium melt redox state compensates for the high-temperature reducing atmosphere and suppresses Fe 2+ Isochromatic centers are generated; CeO2 is generated as Ce 4+ The primary component, combined with oxidation and chemical decolorization, neutralizes redox impurities and weakens transition metal ion coloring through ionic effects. CoO, as a complementary decolorizing ion, selectively absorbs and compensates for the yellow-green hue produced by impurities such as iron, achieving physical complementary decolorization. Multiple components synergistically regulate the melt's redox environment, eliminate bubbles, oxidize coloring impurities, and complementaryly absorb colored light, suppressing glass coloring at its source and significantly improving the 460nm visible light transmittance.

[0048] Meanwhile, the proportions of Sb₂O₃, SO₃, SnO₂, CeO₂, and CoO in this invention must be strictly controlled because each component is a variable-valence oxide or complementary decolorizing ion, collectively forming a redox buffer system and a decolorization system. If the content is too low, insufficient clarification, residual bubbles, and impurities will occur, along with Ti. 3+ 、Nb 4+ Coloration cannot be suppressed, leading to a decrease in transmittance; when the content is too high, it can form color centers or characteristic absorption: Sb 5+ Ce 4+ It will enhance ultraviolet-shortwave absorption, Sn 4+ Excessive amounts of CoO can easily produce reducing colors, while excessive CoO introduces significant visible absorption. At the same time, excessive ions can easily cause phase separation, scattering, and devitrification, which also significantly reduce visible light transmittance. Only by precisely proportioning within the above range can a synergistic balance of clarification, oxidation, decolorization, and devitrification prevention be achieved, ensuring that the glass has high internal transmittance in short-wavelength bands such as 460nm.

[0049] In some embodiments, in step S2, the mixture is put into a crucible without coloring elements for pre-melting. The crucible without coloring elements is made of a material resistant to high-temperature glass melt erosion, and the material of the crucible without coloring elements includes at least one of quartz, corundum, zirconium, etc.

[0050] In some embodiments, in step S2, the mixture is added to a quartz crucible, corundum crucible, or zirconium crucible in several batches for pre-melting.

[0051] Optionally, the quartz crucible has a SiO2 purity of ≥99.995%, preferably ≥99.999%, and the crucible is uniformly dense with a relative density of ≥99.1% (theoretical density 2.22 g / cm³). 3 The porosity is ≤0.5% or ≤0.9% (the upper limit can be selected according to different product requirements), with almost closed pores and no through pores; and the surface roughness is extremely low, with inner wall Ra ≤0.2μm or ≤0.4μm (the upper limit can be selected according to different product requirements).

[0052] Optionally, the corundum crucible has an α-Al₂O₃ purity of ≥99.9%, preferably ≥99.99%, and the crucible is uniformly dense with a relative density of ≥95% (theoretical density ≈ 3.99 g / cm³). 3 The apparent porosity is ≤0.5% or ≤1.5% (the upper limit can be selected according to different product requirements), with almost closed pores and no through pores; and the surface roughness is extremely low, with inner wall Ra≤0.4μm.

[0053] Optionally, the zirconium crucible has a ZrO2 purity of ≥99.8%, preferably ≥99.95%, and the crucible is uniformly dense with a relative density of ≥99.5% (theoretical density of ZrO2 ≈ 6.1 g / cm³). 3 The porosity is close to 0%, with almost closed pores and no through pores; and the surface roughness is extremely low, with inner wall Ra≤0.1μm or≤0.2μm (the upper limit can be selected according to different product requirements).

[0054] In some embodiments, the pre-melting temperature in step S2 is 1150-1350℃ (including but not limited to 1150℃, 1200℃, 1250℃, 1300℃, 1350℃), and the time is 5-20h (including but not limited to 5h, 10h, 15h, 20h).

[0055] In some embodiments, during the pre-melting process in step S2, the flow rate of the inert protective gas or oxygen introduced is 0.2-5 L / min (including but not limited to 0.2 L / min, 0.5 L / min, 1 L / min, 2 L / min, 3 L / min, 4 L / min, and 5 L / min). The residual gas in the prepared glass slag can inhibit the corrosion of noble metals during the secondary melting process. The inert protective gas is at least one of N2, Ar, He, and Ne.

[0056] In some embodiments, when preparing Nb-containing optical glass using this method, an inert protective gas is introduced during the pre-melting process.

[0057] In some embodiments, oxygen is introduced during the pre-melting process of the method for preparing Nb-containing optical glass, which is used to prepare Nb-containing borosilicate optical glass.

[0058] This invention introduces inert gases such as N2 or Ar into the molten glass during the pre-melting process. The core function is twofold: firstly, to isolate air from contact with the batch materials, inhibiting the premature oxidation of easily oxidizable impurities in the raw materials (such as low-valent iron and titanium compounds) into coloring ions; and secondly, to quickly expel volatile gases such as CO2 and H2O generated by the thermal decomposition of the batch materials, reducing residual bubbles. On the other hand, the inert gas maintains the inert environment of the pre-melting system, and some of the inert gas enters the glass slag, inhibiting the reaction between platinum and oxygen during secondary melting, protecting platinum from corrosion by the molten glass, thereby improving transmittance.

[0059] In some embodiments, in steps S3 and S4, the glass slag is added to a precious metal crucible for secondary melting, stirring, clarification and homogenization, and the precious metal crucible has strong corrosion resistance.

[0060] Optionally, the precious metal crucible is made of zirconium-reinforced Pt, wherein the zirconium oxide content is 1100~2300ppm.

[0061] In some embodiments, the secondary melting temperature in step S3 is 1200-1360℃ (including but not limited to 1200℃, 1250℃, 1300℃, 1350℃, 1360℃), and the melting time is 3-10h (including but not limited to 3h, 5h, 8h, 10h).

[0062] In some embodiments, the stirring in step S3 is carried out using a frame stirrer with a speed of 20-60 rpm (including but not limited to 20 rpm, 30 rpm, 40 rpm, 50 rpm, 60 rpm) and a stirring time of 2-10 h (including but not limited to 2 h, 4 h, 6 h, 8 h, 10 h).

[0063] In some embodiments, during the secondary melting and stirring process in step S3, a mixture of halogen-containing gas and inert protective gas (preferably with a volume ratio of 1:10) is introduced. The flow rate of the halogen-containing gas is 0.1-0.3 L / min (including but not limited to 0.1 L / min, 0.15 L / min, 0.2 L / min, 0.25 L / min, and 0.3 L / min), and the flow rate of the inert protective gas is 1-3 L / min (including but not limited to 1 L / min, 1.5 L / min, 2 L / min, 2.5 L / min, and 3 L / min). This serves two purposes: firstly, the halogens react with the coloring elements Fe and Pt to form halides that volatilize at high temperatures; and secondly, the inert protective gas protects the precious metals from corrosion by the molten glass. The inert protective gas is at least one of N2, Ar, He, and Ne.

[0064] Optionally, the halogen-containing gas is at least one of Cl2, CCl4, and CF4.

[0065] In some embodiments, during the secondary melting process in step S3, halides are added to the glass slag, and an inert protective gas is introduced during the secondary melting and stirring process. The flow rate of the inert protective gas is 1-3 L / min. On the one hand, the inert protective gas reacts with the coloring elements Fe and Pt to form halides that volatilize at high temperatures; on the other hand, it protects the precious metals from being corroded by the molten glass. The inert protective gas is at least one of N2, Ar, He, and Ne.

[0066] Optionally, the halide is at least one of KF, LiF, NaCl, etc., and the amount of halide added accounts for 0.3~2% of the mass of the glass slag.

[0067] In this invention, a mixture of halogen-containing gas (or a halide directly added as a substitute) and an inert protective gas is introduced during the secondary melting and stirring process. The gas can be introduced from the bottom of the crucible, along the crucible wall, or above the liquid surface. The halogen acts as a clarification and purification medium, reacting with low-valence metal ions (such as Ti) in the molten glass. 3+ Fe 2+ Coloring ions and impurities form volatile halides, which are discharged with the gas, eliminating visible light absorption caused by coloring ions at the source. Simultaneously, halogens reduce the surface tension of the molten glass, promoting the aggregation and upward movement of microbubbles during melting, thus reducing bubble defects. The inert protective gas, acting as a dilution gas, prevents excessive oxidation of the molten glass and crucible due to excessive halogens, thus preventing the formation of Sb. 5+ Ce 4+ The presence of excess strongly absorbing ions, while maintaining stable system pressure, inhibits glass melt evaporation, ensures melt uniformity, reduces light scattering caused by component inhomogeneity and bubbles, and improves internal transmittance. Simultaneously, the inert protective gas also protects the precious metal crucible, inhibiting its corrosion by the glass melt.

[0068] In some embodiments, the mixture of inert protective gas and oxidizing gas (preferably with a volume ratio of 3:7) introduced during step S4 clarification-homogenization has the following flow rates: the inert protective gas has a flow rate of 0.2-0.7 L / min (including but not limited to 0.2 L / min, 0.3 L / min, 0.4 L / min, 0.5 L / min, 0.6 L / min, and 0.7 L / min), and the oxidizing gas has a flow rate of 0.5-1.7 L / min (including but not limited to 0.5 L / min, 0.8 L / min, 1 L / min, 1.2 L / min, 1.5 L / min, and 1.7 L / min). The inert protective gas is at least one of N2, Ar, He, and Ne; and the oxidizing gas is at least one of O2 and air.

[0069] In some embodiments, the preheating temperature of the mold in step S5 is 300-700℃ (including but not limited to 300℃, 400℃, 500℃, 600℃, 700℃), and the molding temperature is 1100-1350℃ (including but not limited to 1100℃, 1150℃, 1200℃, 1250℃, 1300℃, 1350℃).

[0070] In some implementations, step S5 involves pouring or casting molten glass into a mold to form the shape.

[0071] In some embodiments, during step S5, a mixture of inert protective gas and oxidizing gas (preferably with a volume ratio of 3:7) is introduced. The flow rate of the inert protective gas is 0.2-0.7 L / min (including but not limited to 0.2 L / min, 0.3 L / min, 0.4 L / min, 0.5 L / min, 0.6 L / min, and 0.7 L / min), and the flow rate of the oxidizing gas is 0.5-1.7 L / min (including but not limited to 0.5 L / min, 0.8 L / min, 1 L / min, 1.2 L / min, 1.5 L / min, and 1.7 L / min). The inert protective gas is at least one of N2, Ar, He, and Ne; the oxidizing gas is at least one of O2 and air.

[0072] This invention introduces a mixture of inert protective gas and oxidizing gas above the surface of the molten glass during the clarification, homogenization, and forming processes. This creates a slightly positive pressure oxidizing atmosphere. If necessary, the oxidizing gas can be directly introduced into the molten glass to improve oxidation efficiency, but the flow rate must be strictly limited to avoid excessive gas flow and the generation of bubbles. The oxidizing gas maintains a weakly oxidizing atmosphere in the system, which helps to neutralize residual low-valence coloring ions (such as Ti) in the molten glass. 3+ 、Nb 4+ Oxidation into colorless, high-valence ions inhibits the formation of coloring centers; on the other hand, it can oxidize residual reducing impurities, reducing light absorption caused by impurities. The protective gas can adjust the concentration of oxidizing gas to avoid excessive oxidation leading to glass phase separation, devitrification, and crucible erosion. At the same time, the inertness of the protective gas can prevent the glass surface from being contaminated by impurities in the air during the forming process, reducing surface defects and light scattering. With a reasonable ratio of the two, a thorough clarification, colorless, and defect-free effect can be achieved, ultimately significantly improving the internal transmittance of the glass in the visible light band (especially the 460nm short-wave region).

[0073] In some embodiments, the annealing in step S6 is fine annealing, the annealing temperature is 500-700℃ (including but not limited to 500℃, 550℃, 600℃, 650℃, 700℃), and the annealing time is 4-100h (including but not limited to 4h, 5h, 10h, 20h, 50h, 80h, 100h).

[0074] The Nb-containing optical glass prepared by the above preparation method is either Nb-containing phosphate optical glass or Nb-containing borosilicate optical glass.

[0075] In some embodiments, the composition of the Nb-containing phosphate optical glass comprises, by weight percentage, the following oxide components: P2O5: 10-30%, SiO2: 0%-3%, B2O3: 0-6%, Nb2O5: 20-52%, R2O: 0-10%, MO: 0-30%, ZrO2: 0-2%, TiO2: 10-20%, WO3: 0-10%; wherein R is at least one of Li, Na, and K; and M is at least one of Mg, Ca, Sr, Ba, and Zn.

[0076] In some embodiments, the refractive index n of the Nb-containing phosphate optical glass d ≥1.92, internal transmittance at 460nm ≥92.5%.

[0077] In some embodiments, the composition of the Nb-containing borosilicate optical glass, by weight percentage, includes the following oxide components: B2O3: 1%-20%, SiO2: 3%-20%, Nb2O5: 3-30%, RE2O3: 0-70%, R2O: 0-10%, MO: 0-30%, ZrO2: 0-8%, TiO2: 1-33%, WO3: 0-10%; wherein RE is at least one of La, Y, Gd, and Yb; R is at least one of Li, Na, and K; and M is at least one of Mg, Ca, Sr, Ba, and Zn.

[0078] In some embodiments, the refractive index n of the Nb-containing borosilicate optical glass is... d ≥1.90, internal transmittance at 460nm ≥95%.

[0079] The lens is made of the aforementioned Nb-containing optical glass.

[0080] The above-mentioned Nb-containing optical glass or lenses are used in the manufacture of smartphones, AR / VR glasses, SLR cameras, high-end microscopes, high-definition / ultra-high-definition (4K / 8K) surveillance, automotive and high-end imaging systems, etc.

[0081] Example 1 A method for preparing a high-transmittance Nb phosphate optical glass in the visible light band includes the following steps: (1) Weigh the raw materials according to the following parts by weight: P2O5: 20 parts, Nb2O5: 42 parts, Li2O: 0.5 parts, K2O: 6 parts, Na2O: 1 part, BaO: 3 parts, ZrO2: 0.5 parts, TiO2: 18 parts, WO3: 3 parts, B2O3: 3 parts; SiO2: 1 part, Sb2O3: 0.005 parts, SO3: 0.3 parts, SnO2: 0.3 parts, CeO2: 0.0 parts, CoO: 1.0 parts. Mix these raw materials evenly to obtain a mixture.

[0082] (2) The mixture was added to a quartz crucible without coloring elements in multiple batches and pre-melted at 1250°C under an inert nitrogen atmosphere for 15 hours, with a nitrogen flow rate of 3 L / min. The glass slag after pre-melting was cooled, crushed, washed and dried. The fine glass slag was then transferred to a zirconium-reinforced Pt crucible with strong corrosion resistance after drying.

[0083] (3) The glass material was melted again at 1200℃ for 5 hours. Then, the glass material was stirred at 50 rpm with a frame stirrer, and the temperature was controlled at 1250℃ for 2 hours. During the second melting and stirring, a mixture of chlorine and nitrogen gas was introduced, with a chlorine flow rate of 0.1 L / min and a nitrogen flow rate of 1 L / min.

[0084] (4) After the stirring process is completed, let it stand and clarify for 5 hours, and at the same time, a mixture of nitrogen and oxygen gas is introduced (until the glass forming is completed). The nitrogen flow rate is 0.3 L / min and the oxygen flow rate is 0.7 L / min.

[0085] (5) Preheat the molding mold to 600°C in advance, and the temperature of the glass melt in the crucible is 1200°C before molding.

[0086] (6) Anneal the formed glass at a temperature of 650°C for 50 hours.

[0087] The refractive index n of the Nb-containing optical glass obtained in this embodiment is... d The transmittance of the 10 mm thick sample was 93.2% at 460 nm, with a value of 1.932.

[0088] Example 2 A method for preparing a high-transmittance Nb phosphate optical glass in the visible light band includes the following steps: (1) Weigh the raw materials according to the following parts by weight: P2O5: 20 parts, Nb2O5: 42 parts, Li2O: 0.5 parts, K2O: 6 parts, Na2O: 1 part, BaO: 3 parts, ZrO2: 0.5 parts, TiO2: 18 parts, WO3: 3 parts, B2O3: 3 parts; SiO2: 1 part, Sb2O3: 0.005 parts, SO3: 0.3 parts, SnO2: 0.3 parts, CeO2: 0.0 parts, CoO: 1.0 parts. Mix these raw materials evenly to obtain a mixture.

[0089] (2) The mixture was added to a quartz crucible without coloring elements in multiple batches and pre-melted at 1250°C under an inert nitrogen atmosphere for 15 hours, with a nitrogen flow rate of 3 L / min. After pre-melting, the glass slag was cooled, crushed, washed and dried, and then transferred to a zirconium-reinforced Pt crucible with strong corrosion resistance.

[0090] (3) A second melting was carried out at 1200℃ for 5 hours. Then, the glass material was stirred at 50 rpm with a frame stirrer, and the temperature was controlled at 1250℃ for 2 hours. During the second melting and stirring, a mixture of chlorine and nitrogen gas was introduced, with a chlorine flow rate of 0.2 L / min and a nitrogen flow rate of 2 L / min.

[0091] (4) After the stirring process is completed, let it stand and clarify for 5 hours, and at the same time, a mixture of nitrogen and oxygen gas is introduced (until the glass forming is completed). The nitrogen flow rate is 0.3 L / min and the oxygen flow rate is 0.7 L / min.

[0092] (5) Preheat the molding mold to 600°C in advance, and the temperature of the glass melt in the crucible is 1200°C before molding.

[0093] (6) Anneal the formed glass at a temperature of 650°C for 50 hours.

[0094] The refractive index n of the Nb-containing optical glass obtained in this embodiment is... d The transmittance of the 10 mm thick sample was 93.6% at 460 nm, with a value of 1.932.

[0095] Example 3 A method for preparing a high-transmittance Nb phosphate optical glass in the visible light band includes the following steps: (1) Weigh the raw materials according to the following parts by weight: P2O5: 20 parts, Nb2O5: 42 parts, Li2O: 0.5 parts, K2O: 6 parts, Na2O: 1 part, BaO: 3 parts, ZrO2: 0.5 parts, TiO2: 18 parts, WO3: 3 parts, B2O3: 3 parts; SiO2: 1 part, Sb2O3: 0.005 parts, SO3: 0.3 parts, SnO2: 0.3 parts, CeO2: 0.0 parts, CoO: 1.5 parts. Mix these raw materials evenly to obtain a mixture.

[0096] (2) The mixture was added to a quartz crucible without coloring elements in multiple batches and pre-melted at 1250°C under an inert nitrogen atmosphere for 15 hours, with a nitrogen flow rate of 3 L / min. After pre-melting, the glass slag was cooled, crushed, washed and dried, and then transferred to a zirconium-reinforced Pt crucible with strong corrosion resistance.

[0097] (3) A second melting was carried out at 1200℃ for 5 hours. Then, the glass material was stirred at 50 rpm with a frame stirrer, and the temperature was controlled at 1250℃ for 2 hours. During the second melting and stirring, a mixture of chlorine and nitrogen gas was introduced, with a chlorine flow rate of 0.2 L / min and a nitrogen flow rate of 2 L / min.

[0098] (4) After the stirring process is completed, let it stand and clarify for 5 hours, and at the same time, a mixture of nitrogen and oxygen gas is introduced (until the glass forming is completed). The nitrogen flow rate is 0.3 L / min and the oxygen flow rate is 0.7 L / min.

[0099] (5) Preheat the molding mold to 600°C in advance, and the temperature of the glass melt in the crucible is 1200°C before molding.

[0100] (6) Anneal the formed glass at a temperature of 650°C for 50 hours.

[0101] The refractive index n of the Nb-containing optical glass obtained in this embodiment is... d The transmittance of the 10 mm thick sample was 94.7% at 460 nm, which is 1.933.

[0102] Example 4 A method for preparing a high-transmittance Nb phosphate optical glass in the visible light band includes the following steps: (1) Weigh the raw materials according to the following parts by weight: P2O5: 20 parts, Nb2O5: 42 parts, Li2O: 0.5 parts, K2O: 6 parts, Na2O: 1 part, BaO: 3 parts, ZrO2: 0.5 parts, TiO2: 18 parts, WO3: 3 parts, B2O3: 3 parts; SiO2: 1 part, Sb2O3: 0.005 parts, SO3: 0.3 parts, SnO2: 0.1 parts, CeO2: 0.1 parts, CoO: 1.5 parts. Mix these raw materials evenly to obtain a mixture.

[0103] (2) The mixture was added to a quartz crucible without coloring elements in multiple batches and pre-melted at 1250°C under an inert nitrogen atmosphere for 15 hours, with a nitrogen flow rate of 3 L / min. After pre-melting, the glass slag was cooled, crushed, washed and dried, and then transferred to a zirconium-reinforced Pt crucible with strong corrosion resistance.

[0104] (3) A second melting was carried out at 1200℃ for 5 hours. Then, the glass material was stirred at 50 rpm with a frame stirrer, and the temperature was controlled at 1250℃ for 2 hours. During the second melting and stirring, a mixture of chlorine and nitrogen gas was introduced, with a chlorine flow rate of 0.2 L / min and a nitrogen flow rate of 2 L / min.

[0105] (4) After the stirring process is completed, let it stand and clarify for 5 hours, and at the same time, a mixture of nitrogen and oxygen gas is introduced (until the glass forming is completed). The nitrogen flow rate is 0.3 L / min and the oxygen flow rate is 0.7 L / min.

[0106] (5) Preheat the molding mold to 600°C in advance, and the temperature of the glass melt in the crucible is 1200°C before molding.

[0107] (6) Anneal the formed glass at a temperature of 650°C for 50 hours.

[0108] The Nb-containing optical glass obtained in this embodiment has a refractive index nd of 1.933, and the transmittance of a 10 mm thick sample is 95.2% at 460 nm.

[0109] Example 5 A method for preparing a high-transmittance Nb phosphate optical glass in the visible light band includes the following steps: (1) Weigh the raw materials according to the following parts by weight: P2O5: 20 parts, Nb2O5: 42 parts, Li2O: 0.5 parts, K2O: 6 parts, Na2O: 1 part, BaO: 3 parts, ZrO2: 0.5 parts, TiO2: 18 parts, WO3: 3 parts, B2O3: 3 parts; SiO2: 1 part, Sb2O3: 0.003 parts, SO3: 0.3 parts, SnO2: 0.1 parts, CeO2: 0.1 parts, CoO: 1.2 parts. Mix these raw materials evenly to obtain a mixture.

[0110] (2) The mixture was added to a quartz crucible without coloring elements in multiple batches and pre-melted at 1250°C under an inert nitrogen atmosphere for 15 hours, with a nitrogen flow rate of 3 L / min. After pre-melting, the glass slag was cooled, crushed, washed and dried, and then transferred to a zirconium-reinforced Pt crucible with strong corrosion resistance.

[0111] (3) A second melting was carried out at 1200℃ for 5 hours. Then, the glass material was stirred at 50 rpm with a frame stirrer, and the temperature was controlled at 1250℃ for 2 hours. During the second melting and stirring, a mixture of chlorine and nitrogen gas was introduced, with a chlorine flow rate of 0.2 L / min and a nitrogen flow rate of 2 L / min.

[0112] (4) After the stirring process is completed, let it stand and clarify for 5 hours, and at the same time, a mixture of nitrogen and oxygen gas is introduced (until the glass forming is completed). The nitrogen flow rate is 0.3 L / min and the oxygen flow rate is 0.7 L / min.

[0113] (5) Preheat the molding mold to 600°C in advance, and the temperature of the glass melt in the crucible is 1200°C before molding.

[0114] (6) Anneal the formed glass at a temperature of 650°C for 50 hours.

[0115] The refractive index n of the Nb-containing optical glass obtained in this embodiment is... d The transmittance of the 10 mm thick sample was 95.5% at 460 nm, which is 1.933.

[0116] Example 6 A method for preparing high-transmittance Nb-containing optical glass in the visible light band includes the following steps: (1) Weigh the raw materials according to the following parts by weight: B2O3: 7 parts, SiO2: 8 parts, La2O3: 48 parts, Y2O3: 7 parts, Gd2O3: 10 parts, Nb2O5: 5 parts, Li2O: 0.5 parts, ZnO: 5 parts, ZrO2: 5 parts, TiO2: 5 parts, Sb2O3: 0.01 parts, SO3: 0.1 parts, SnO2: 0.5 parts, CeO2: 0.1 parts, CoO: 0.2 parts; (2) The mixture was added to a corundum crucible without coloring elements in multiple batches and pre-melted at 1320°C in an oxygen atmosphere for 15 hours, with an oxygen flow rate of 2 L / min. After pre-melting, the glass slag was cooled, crushed, washed and dried, and then transferred to a zirconium-reinforced Pt crucible with strong corrosion resistance.

[0117] (3) Secondary melting was carried out at 1300℃ for 6 hours. Then, the glass material was stirred at 50 rpm with a frame stirrer, and the temperature was controlled at 1350℃ for 2 hours. During the secondary melting and stirring, a mixture of chlorine and nitrogen gas was introduced, with a chlorine flow rate of 0.15 L / min and a nitrogen flow rate of 1.5 L / min.

[0118] (4) After the stirring process is completed, let it stand and clarify for 5 hours, and at the same time, a mixture of nitrogen and oxygen gas is introduced (until the glass forming is completed). The nitrogen flow rate is 0.3 L / min and the oxygen flow rate is 0.7 L / min.

[0119] (5) Preheat the molding mold to 650°C in advance, and the temperature of the glass melt in the crucible is 1300°C before molding.

[0120] (6) Anneal the formed glass at a temperature of 650°C for 10 hours.

[0121] The refractive index n of the Nb-containing optical glass obtained in this embodiment is... d The transmittance of a 10 mm thick sample is 95.5% at 460 nm, with a value of 1.915.

[0122] Example 7 A method for preparing high-transmittance Nb-containing optical glass in the visible light band includes the following steps: (1) Weigh the raw materials according to the following parts by weight: B2O3: 7 parts, SiO2: 8 parts, La2O3: 48 parts, Y2O3: 7 parts, Gd2O3: 10 parts, Nb2O5: 5 parts, Li2O: 0.5 parts, ZnO: 5 parts, ZrO2: 5 parts, TiO2: 5 parts, Sb2O3: 0.01 parts, SO3: 0.1 parts, SnO2: 0.5 parts, CeO2: 0.5 parts, CoO: 0.2 parts; (2) The mixture was added to a corundum crucible without coloring elements in multiple batches and pre-melted at 1320°C in an oxygen atmosphere for 15 hours, with an oxygen flow rate of 2 L / min. After pre-melting, the glass slag was cooled, crushed, washed and dried, and then transferred to a zirconium-reinforced Pt crucible with strong corrosion resistance.

[0123] (3) Secondary melting was carried out at 1300℃ for 6 hours. Then, the glass material was stirred at 50 rpm with a frame stirrer, and the temperature was controlled at 1350℃ for 2 hours. During the secondary melting and stirring, a mixture of chlorine and nitrogen gas was introduced, with a chlorine flow rate of 0.15 L / min and a nitrogen flow rate of 1.5 L / min.

[0124] (4) After the stirring process is completed, let it stand and clarify for 5 hours, and at the same time, a mixture of nitrogen and oxygen gas is introduced (until the glass forming is completed). The nitrogen flow rate is 0.3 L / min and the oxygen flow rate is 0.7 L / min.

[0125] (5) Preheat the molding mold to 650°C in advance, and the temperature of the glass melt in the crucible is 1300°C before molding.

[0126] (6) Anneal the formed glass at a temperature of 650°C for 10 hours.

[0127] The Nb-containing optical glass obtained in this embodiment has a refractive index nd of 1.918, and the transmittance of a 10 mm thick sample is 95.9% at 460 nm.

[0128] Example 8 A method for preparing high-transmittance Nb-containing optical glass in the visible light band includes the following steps: (1) Weigh the raw materials according to the following parts by weight: B2O3: 7 parts, SiO2: 8 parts, La2O3: 48 parts, Y2O3: 7 parts, Gd2O3: 10 parts, Nb2O5: 5 parts, Li2O: 0.5 parts, ZnO: 5 parts, ZrO2: 5 parts, TiO2: 5 parts, Sb2O3: 0.01 parts, SO3: 0.1 parts, SnO2: 0.5 parts, CeO2: 0.1 parts, CoO: 0.2 parts; (2) The mixture was added to a corundum crucible without coloring elements in multiple batches and pre-melted at 1320°C in an oxygen atmosphere for 15 hours, with an oxygen flow rate of 2 L / min. After pre-melting, the glass slag was cooled, crushed, washed and dried, and then transferred to a zirconium-reinforced Pt crucible with strong corrosion resistance.

[0129] (3) Secondary melting was carried out at 1300℃ for 6 hours. Then, the glass material was stirred at 50 rpm under the action of a frame stirrer, and the temperature was controlled at 1350℃ for 2 hours. During the secondary melting and stirring, a mixture of chlorine and nitrogen gas was introduced, with a chlorine flow rate of 0.1 L / min and a nitrogen flow rate of 1 L / min.

[0130] (4) After the stirring process is completed, let it stand and clarify for 5 hours, and at the same time, a mixture of nitrogen and oxygen gas is introduced (until the glass forming is completed). The nitrogen flow rate is 0.3 L / min and the oxygen flow rate is 0.7 L / min.

[0131] (5) Preheat the molding mold to 650°C in advance, and the temperature of the glass melt in the crucible is 1300°C before molding.

[0132] (6) Anneal the formed glass at a temperature of 650°C for 10 hours.

[0133] The refractive index n of the Nb-containing optical glass obtained in this embodiment is... d The transmittance of the 10 mm thick sample was 96.3% at 460 nm, with a value of 1.915.

[0134] Example 9 A method for preparing high-transmittance Nb-containing optical glass in the visible light band includes the following steps: (1) Weigh the raw materials according to the following parts by weight: B2O3: 7 parts, SiO2: 8 parts, La2O3: 48 parts, Y2O3: 7 parts, Gd2O3: 10 parts, Nb2O5: 5 parts, Li2O: 0.5 parts, ZnO: 5 parts, ZrO2: 5 parts, TiO2: 5 parts, Sb2O3: 0.01 parts, SO3: 0.1 parts, SnO2: 0.5 parts, CeO2: 0.1 parts, CoO: 0.2 parts; (2) The mixture was added to a corundum crucible without coloring elements in multiple batches and pre-melted at 1320°C in an oxygen atmosphere for 15 hours, with an oxygen flow rate of 2 L / min. After pre-melting, the glass slag was cooled, crushed, washed and dried, and then transferred to a zirconium-reinforced Pt crucible with strong corrosion resistance.

[0135] (3) Secondary melting was carried out at 1300℃ for 6 hours. Then, the glass material was stirred at 50 rpm under the action of a frame stirrer, and the temperature was controlled at 1350℃ for 2 hours. During the secondary melting and stirring, a mixture of chlorine and nitrogen gas was introduced, with a chlorine flow rate of 0.1 L / min and a nitrogen flow rate of 1 L / min.

[0136] (4) After the stirring process is completed, let it stand and clarify for 5 hours, and at the same time, a mixture of nitrogen and oxygen gas is introduced (until the glass forming is completed). The nitrogen flow rate is 0.64 L / min and the oxygen flow rate is 1.5 L / min.

[0137] (5) Preheat the molding mold to 650°C in advance, and the temperature of the glass melt in the crucible is 1300°C before molding.

[0138] (6) Anneal the formed glass at a temperature of 650°C for 10 hours.

[0139] The refractive index n of the Nb-containing optical glass obtained in this embodiment is... d The transmittance of a 10 mm thick sample is 96.5% at 460 nm, with a value of 1.915.

[0140] Example 10 A method for preparing high-transmittance Nb-containing optical glass in the visible light band includes the following steps: (1) Weigh the raw materials according to the following weight parts: B2O3: 7 parts, SiO2: 8 parts, La2O3: 48 parts, Y2O3: 7 parts, Gd2O3: 10 parts, Nb2O5: 5 parts, Li2O: 0.5 parts, ZnO: 5 parts, ZrO2: 5 parts, TiO2: 5 parts, Sb2O3: 0.01 parts, SO3: 0.1 parts, SnO2: 0.5 parts, CeO2: 0.1 parts, CoO: 0.2 parts.

[0141] (2) The mixture was added to a zircon crucible without coloring elements in multiple batches and pre-melted at 1320°C in an oxygen atmosphere for 15 hours, with an oxygen flow rate of 2 L / min. After pre-melting, the glass slag was cooled, crushed, washed and dried, and then transferred to a zircon-reinforced Pt crucible with strong corrosion resistance.

[0142] (3) Secondary melting was carried out at 1300℃ for 6 hours. Then, the glass material was stirred at 50 rpm under the action of a frame stirrer, and the temperature was controlled at 1350℃ for 2 hours. During the secondary melting and stirring, a mixture of chlorine and nitrogen gas was introduced, with a chlorine flow rate of 0.1 L / min and a nitrogen flow rate of 1 L / min.

[0143] (4) After the stirring process is completed, let it stand and clarify for 5 hours, and at the same time, a mixture of nitrogen and oxygen gas is introduced (until the glass forming is completed). The nitrogen flow rate is 0.64 L / min and the oxygen flow rate is 1.5 L / min.

[0144] (5) Preheat the molding mold to 650°C in advance, and the temperature of the glass melt in the crucible is 1300°C before molding.

[0145] (6) Anneal the formed glass at a temperature of 650°C for 10 hours.

[0146] The refractive index n of the Nb-containing optical glass obtained in this embodiment is... d The transmittance is 96.5% at 460 nm for a 10 mm thick sample with a value of 1.916.

[0147] Comparative Example 1 The difference between this comparative example and Example 1 is that no composite clarifying agent-oxidizing agent is added to the raw materials; a pure platinum crucible is used, and melting is carried out in an air atmosphere. Everything else is the same as in Example 1.

[0148] Comparative Example 2 The difference between this comparative example and Example 1 is that: no Li2O and composite clarifying agent-oxidant are added to the raw materials; no pre-melting is performed, and a pure platinum crucible is used directly for melting in an air atmosphere; the melting, stirring, and clarifying temperatures are each increased by 30°C compared to Example 1, otherwise the melting will be insufficient and there will be many bubbles. The rest is the same as Example 1.

[0149] Comparative Example 3 The difference between this comparative example and Example 1 is that the raw material composition is the same as in Example 1, and a pure platinum crucible and air atmosphere are used for melting. Everything else is the same as in Example 1.

[0150] Comparative Example 4 The difference between this comparative example and Example 1 is that the raw material composition is the same as in Example 1, a zirconium-reinforced platinum crucible (purity 99.9%, Ra > 3 μm) is used, and conventional melting is performed in an air atmosphere. Everything else is the same as in Example 1.

[0151] Comparative Example 5 The difference between this comparative example and Example 1 is that the raw material composition is the same as in Example 1, but after pre-melting in an ordinary quartz crucible (purity 99.9%, Ra > 3μm), the glass slag is transferred to a zirconium-reinforced platinum crucible for secondary melting, stirring, clarification, and homogenization (in air atmosphere). The rest is the same as in Example 1.

[0152] Comparative Example 6 The difference between this comparative example and Example 1 is that chlorine gas is not introduced, while the introduction of other gases remains unchanged. Everything else is the same as in Example 1.

[0153] Comparative Example 7 The difference between this comparative example and Example 1 is that nitrogen gas is only introduced during the pre-melting process, and not during other stages. The rest is the same as Example 1.

[0154] Comparative Example 8 The difference between this comparative example and Example 1 is as follows: The raw material composition of this comparative example is: P2O5: 20 parts, Nb2O5: 42 parts, Li2O: 0.5 parts, K2O: 6 parts, Na2O: 1 part, BaO: 3 parts, ZrO2: 0.5 parts, TiO2: 18 parts, WO3: 3 parts, B2O3: 3 parts; SiO2: 1 part, Sb2O3: 0.005 parts, SO3: 0.3 parts, SnO2: 0.3 parts, CeO2: 0.0 parts, CoO: 3.0 parts. The rest is the same as in Example 1.

[0155] Comparative Example 9 The difference between this comparative example and Example 1 is that the raw material composition of this comparative example is: P2O5: 20 parts, Nb2O5: 42 parts, Li2O: 0.5 parts, K2O: 6 parts, Na2O: 1 part, BaO: 3 parts, ZrO2: 0.5 parts, TiO2: 18 parts, WO3: 3 parts, B2O3: 3 parts; SiO2: 1 part, Sb2O3: 0.005 parts, SO3: 0.3 parts, SnO2: 0.3 parts, CeO2: 1.0 part, CoO: 3.0 parts. The rest is the same as in Example 1.

[0156] Comparative Example 10 The difference between this comparative example and Example 6 is that the raw material composition of this comparative example is: B2O3: 7 parts, SiO2: 8 parts, La2O3: 48 parts, Y2O3: 7 parts, Gd2O3: 10 parts, Nb2O5: 5 parts, Li2O: 0.5 parts, ZnO: 5 parts, ZrO2: 5 parts, TiO2: 5 parts, Sb2O3: 0.01 parts. A pure platinum crucible was used, and melting was performed in an air atmosphere. The rest is the same as in Example 6.

[0157] Comparative Example 11 The difference between this comparative example and Example 6 is that the raw material composition of this comparative example is: B2O3: 7 parts, SiO2: 8 parts, La2O3: 48 parts, Y2O3: 7 parts, Gd2O3: 10 parts, Nb2O5: 5 parts, Li2O: 0.5 parts, ZnO: 5 parts, ZrO2: 5 parts, TiO2: 5 parts, Sb2O3: 0.01 parts. Pre-melting (homogenization by introducing oxygen) was performed using a quartz crucible, followed by melting in an air atmosphere using a pure platinum crucible. The rest is the same as in Example 6.

[0158] Comparative Example 12 The difference between this comparative example and Example 6 is that a quartz crucible was used for pre-melting (homogenization by introducing oxygen), and then a pure platinum crucible was used for melting in an air atmosphere. The rest is the same as Example 6.

[0159] Test case The physicochemical properties of Comparative Examples 1 to 12 and the resulting performance data of Nb-containing optical glasses are shown in Table 1.

[0160] Table 1. Physicochemical properties and performance data of Nb-containing optical glasses for Comparative Examples 1-12

[0161] Based on the data in Table 1 Figures 1-2 It is known that using ordinary quartz crucibles for pre-melting will reduce the glass's refractive index. Using pure platinum crucibles, not introducing chlorine gas, reducing nitrogen introduction time, adding unsuitable composite oxidant-clarifying agent components, and not performing pre-melting will all lead to a decrease in transmittance. Therefore, to obtain high-transmittance, high-refractive-index glass, it is essential to strictly control the composition of the main components and the ratio of the composite oxidant-clarifying agent, use crucibles that are corrosion-resistant and do not easily introduce coloring elements, and carefully control the type, flow rate, and timing of the atmosphere.

[0162] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing Nb-containing optical glass, characterized in that, Includes the following steps: Step S1, Raw material mixing: Weigh the raw materials according to the component ratio of Nb-containing optical glass, and mix them evenly to obtain a mixture; Step S2, Pre-melting: Inert protective gas or oxygen is introduced into the mixture for pre-melting to obtain glass slag; Step S3, Secondary Melting: The glass slag is melted and stirred a second time to obtain molten glass; Step S4, Clarification-Homogeneity: A mixture of inert protective gas and oxidizing gas is introduced into the molten glass to perform clarification-homogenization; Step S5, Forming: The clarified and homogenized molten glass is injected into the mold for forming. During the forming process, a mixture of inert protective gas and oxidizing gas is introduced. Step S6, Annealing: Anneal the formed glass to obtain Nb-containing optical glass products.

2. The method for preparing Nb-containing optical glass according to claim 1, characterized in that, The composition ratio of the Nb-containing optical glass in step S1, by weight percentage, includes the following oxide components: B2O3+SiO2+P2O5: 4-40%, Nb2O5: 3-52%, RE2O3: 0-70%, R2O: 0-10%, MO: 0-30%, ZrO2: 0-8%, TiO2+WO3: 0-43%, Ta2O5: 0-20%; wherein, the contents of B2O3, SiO2, and P2O5 in B2O3+SiO2+P2O5 can all be 0%, but the contents of the three cannot be 0% at the same time; RE is at least one of La, Y, Gd, and Yb; R is at least one of Li, Na, and K; and M is at least one of Mg, Ca, Sr, Ba, and Zn.

3. The method for preparing Nb-containing optical glass according to claim 2, characterized in that, It should include at least one of the following technical features: (1) The R2O comprises at least 0.2-1.0% Li2O; (2) The raw materials mentioned in step S1 also include a composite clarifying agent-oxidizing agent, which includes the following components by weight percentage: Sb2O3: 0.001-0.02%, SO3: 0.002-0.6%, SnO2: 0.00-1.0%, CeO2: 0.00-1.0%, CoO: 0.00-2.0%.

4. The method for preparing Nb-containing optical glass according to claim 3, characterized in that, It should include at least one of the following technical features: (1) In step S2, the mixture is put into a quartz crucible, a corundum crucible or a zircon crucible for pre-melting; (2) The pre-melting temperature in step S2 is 1150-1350℃ and the time is 5-20h; (3) The flow rate of inert protective gas or oxygen introduced during the pre-melting process in step S2 is 0.2-5 L / min; (4) When preparing Nb-containing phosphate optical glass, an inert protective gas is introduced during the pre-melting process; (5) When preparing Nb-containing borosilicate optical glass, oxygen is introduced during the pre-melting process.

5. The method for preparing Nb-containing optical glass according to claim 4, characterized in that, It should include at least one of the following technical features: (1) In steps S3 and S4, the glass slag is put into a precious metal crucible for secondary melting, stirring, clarification and homogenization; (2) The secondary melting temperature in step S3 is 1200-1360℃, and the melting time is 3-10h; (3) In step S3, the stirring speed is 20-60 rpm and the stirring time is 2-10 h; (4) In step S3, during the secondary melting and stirring process, a mixture of halogen-containing gas and inert protective gas is introduced, wherein the flow rate of the halogen-containing gas is 0.1-0.3 L / min and the flow rate of the inert protective gas is 1-3 L / min; (5) In step S3, halide is added to the glass slag during the secondary melting process, and inert protective gas is introduced during the secondary melting and stirring process. The flow rate of the inert protective gas is 1-3 L / min.

6. The method for preparing Nb-containing optical glass according to claim 5, characterized in that, It should include at least one of the following technical features: (1) The halogen-containing gas is at least one of Cl2, CCl4, and CF4; (2) The halide is at least one of KF, LiF, and NaCl; (3) The amount of halide added accounts for 0.3~2% of the mass of the glass slag.

7. The method for preparing Nb-containing optical glass according to claim 5, characterized in that, It should include at least one of the following technical features: (1) The mixture of inert protective gas and oxidizing gas introduced during the clarification-homogenization process in step S4, wherein the flow rate of the inert protective gas is 0.2-0.7 L / min and the flow rate of the oxidizing gas is 0.5-1.7 L / min; (2) In step S5, the preheating temperature of the mold before molding is 300-700℃, and the molding temperature is 1100-1350℃; (3) In step S5, the molten glass is poured or poured into the mold to form the shape; (4) During the molding process in step S5, a mixture of inert protective gas and oxidizing gas is introduced, wherein the flow rate of the inert protective gas is 0.2-0.7 L / min and the flow rate of the oxidizing gas is 0.5-1.7 L / min; (5) The annealing in step S6 is fine annealing; (6) The annealing temperature in step S6 is 500-700℃ and the annealing time is 4-100h.

8. The Nb-containing optical glass prepared by the preparation method according to any one of claims 1 to 7, characterized in that, The Nb-containing optical glass is either Nb-containing phosphate optical glass or Nb-containing borosilicate optical glass; The composition of the Nb-containing phosphate optical glass, by weight percentage, includes the following oxide components: P2O5: 10-30%, SiO2: 0%-3%, B2O3: 0-6%, Nb2O5: 20-52%, R2O: 0-10%, MO: 0-30%, ZrO2: 0-2%, TiO2: 10-20%, WO3: 0-10%; wherein R is at least one of Li, Na, and K; and M is at least one of Mg, Ca, Sr, Ba, and Zn. The composition of the Nb-containing borosilicate optical glass, by weight percentage, includes the following oxide components: B2O3: 1%-20%, SiO2: 3%-20%, Nb2O5: 3-30%, RE2O3: 0-70%, R2O: 0-10%, MO: 0-30%, ZrO2: 0-8%, TiO2: 1-33%, WO3: 0-10%; wherein RE is at least one of La, Y, Gd, and Yb; R is at least one of Li, Na, and K; and M is at least one of Mg, Ca, Sr, Ba, and Zn.

9. The lens made of Nb-containing optical glass as described in claim 8.

10. The application of the Nb-containing optical glass as described in claim 8 or the lens as described in claim 9 in the manufacture of smartphones, AR / VR glasses, SLR cameras, high-end microscopes, high-definition / ultra-high-definition surveillance, automotive and high-end imaging systems.

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