Optical glass, glass preforms, optical components and optical instruments

Abstract

This invention provides an optical glass whose composition, expressed as a weight percentage, contains: SiO2: 2-18%; B2O3: 8-22%; La2O3: 40-60%; Y2O3: 3-18%; ZrO2: 1-15%; Nb2O5: 2-15%. Through reasonable composition design, the optical glass obtained by this invention exhibits excellent devitrification resistance and chemical stability.

Description

Technical Field

[0001] This invention relates to an optical glass, and more particularly to an optical glass with a refractive index nd of 1.82 to 1.89 and an Abbe number vd of 37 to 44, as well as glass preforms, optical elements and optical instruments made therefrom. Prior Technology

[0002] Optical glasses with a refractive index (nd) of 1.82–1.89 and an Abbe number (vd) of 37–44 are high-refractive-index optical glasses. They are widely used in the manufacture of lenses, prisms, mirrors, and windows in optical instruments and mechanical systems. However, the devitrification resistance and chemical stability of existing optical glasses with a refractive index (nd) of 1.82–1.89 and an Abbe number (vd) of 37–44 need improvement. For example, CN110937802A discloses an optical glass with a refractive index (nd) of 1.75–1.85 and an Abbe number (vd) of 34–40, and CN106810066A discloses an optical glass with a refractive index (nd) of 1.80–1.90 and an Abbe number (vd) of 30–40. Therefore, developing a high-refractive-index optical glass with excellent devitrification resistance and chemical stability is of great significance to the development of the optoelectronic field. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide an optical glass with excellent resistance to devitrification and chemical stability.

[0004] The technical solution adopted by this invention to solve the technical problem is:

[0005] An optical glass, the composition of which is expressed as a weight percentage, contains: SiO2: 2~18%; B2O3: 8~22%; La2O3: 40~60%; Y2O3: 3~18%; ZrO2: 1~15%; Nb2O5: 2~15%.

[0006] Furthermore, the optical glass, in weight percentage, further contains: Ta₂O₅: 0~10%; and / or Gd₂O₃: 0~9%; and / or TiO₂: 0~6%; and / or RO: 0~10%; and / or Rn₂O: 0~8%; and / or WO₃: 0~8%; and / or ZnO: 0~10%; and / or Al₂O₃: 0~5%; and / or Yb₂O₃: 0~8%; and / or GeO₂: 0~5%; and / or clarifying agent: 0~1%, wherein RO is one or more of MgO, CaO, SrO, and BaO, Rn₂O is one or more of Li₂O, Na₂O, and K₂O, and the clarifying agent is one or more of Sb₂O₃, SnO, SnO₂, and CeO₂.

[0007] An optical glass, the composition of which is expressed as a weight percentage, comprises: SiO₂: 2-18%; B₂O₃: 8-22%; La₂O₃: 40-60%; Y₂O₃: 3-18%; ZrO₂: 1-15%; Nb₂O₅: 2-15%; Ta₂O₅: 0-10%; Gd₂O₃: 0-9%; TiO₂: 0-6%; RO: 0-10%; Rn₂O: 0-8%; WO₃: 0-8%; ZnO: 0-10%; Al₂O₃: 0-5%; Yb₂O₃: 0-8%; GeO₂: 0-5%; and a clarifying agent: 0-1%. The RO is one or more of MgO, CaO, SrO, and BaO, and the Rn₂O is Li₂O, Na₂O, or K₂O. One or more of 2O, and the clarifying agent is one or more of Sb 2O 3, SnO, SnO 2, CeO 2.

[0008] Furthermore, the composition of the optical glass is expressed as a weight percentage, wherein: (ZnO+Ta₂O₅) / Nb₂O₅ is 2.0 or less, preferably (ZnO+Ta₂O₅) / Nb₂O₅ is 1.5 or less, more preferably (ZnO+Ta₂O₅) / Nb₂O₅ is 1.0 or less, and even more preferably (ZnO+Ta₂O₅) / Nb₂O₅ is 0.1 to 0.8.

[0009] Furthermore, the composition of the optical glass is expressed as a weight percentage, wherein: (Gd₂O₃+Ta₂O₅+WO₃) / La₂O₃ is 0.5 or less, preferably (Gd₂O₃+Ta₂O₅+WO₃) / La₂O₃ is 0.4 or less, more preferably (Gd₂O₃+Ta₂O₅+WO₃) / La₂O₃ is 0.3 or less, and even more preferably (Gd₂O₃+Ta₂O₅+WO₃) / La₂O₃ is 0.2 or less.

[0010] Furthermore, the composition of the optical glass is expressed as a weight percentage, wherein: (Ta₂O₅+Gd₂O₃) / Y₂O₃ is 1.0 or less, preferably (Ta₂O₅+Gd₂O₃) / Y₂O₃ is 0.8 or less, more preferably (Ta₂O₅+Gd₂O₃) / Y₂O₃ is 0.5 or less, and even more preferably (Ta₂O₅+Gd₂O₃) / Y₂O₃ is 0.2 or less.

[0011] Furthermore, the composition of the optical glass is expressed as a weight percentage, wherein: La₂O₃ / (B₂O₃+Nb₂O₅) is 1.2~5.0, preferably La₂O₃ / (B₂O₃+Nb₂O₅) is 1.3~4.0, more preferably La₂O₃ / (B₂O₃+Nb₂O₅) is 1.5~3.5, and even more preferably La₂O₃ / (B₂O₃+Nb₂O₅) is 1.7~2.7.

[0012] Furthermore, the composition of the optical glass is expressed as a weight percentage, wherein: (ZnO+WO3) / Nb2O5 is 3.0 or less, preferably (ZnO+WO3) / Nb2O5 is 2.0 or less, more preferably (ZnO+WO3) / Nb2O5 is 1.5 or less, and even more preferably (ZnO+WO3) / Nb2O5 is 0.2 to 1.0.

[0013] Furthermore, the composition of the optical glass is expressed as a weight percentage, wherein: (B₂O₃+RO) / La₂O₃ is 0.15~0.7, preferably (B₂O₃+RO) / La₂O₃ is 0.15~0.6, more preferably (B₂O₃+RO) / La₂O₃ is 0.18~0.5, and even more preferably (B₂O₃+RO) / La₂O₃ is 0.2~0.4, wherein RO is one or more of MgO, CaO, SrO, and BaO.

[0014] Furthermore, the composition of the optical glass is expressed as a weight percentage, wherein: (Gd₂O₃+ZnO) / Y₂O₃ is 2.0 or less, preferably (Gd₂O₃+ZnO) / Y₂O₃ is 1.5 or less, more preferably (Gd₂O₃+ZnO) / Y₂O₃ is 1.0 or less, and even more preferably (Gd₂O₃+ZnO) / Y₂O₃ is 0.8 or less.

[0015] Furthermore, the optical glass comprises, by weight percentage: SiO₂: 4-15%, preferably SiO₂: 6-12%; and / or B₂O₃: 10-20%, preferably B₂O₃: 12-18%; and / or La₂O₃: 43-55%, preferably La₂O₃: 46-52%; and / or Y₂O₃: 5-15%, preferably Y₂O₃: 7-13%; and / or ZrO₂: 2-12%, preferably ZrO₂: 3-10%; and / or Nb₂O₅: 3-13%, preferably Nb₂O₅: 5-11%; and / or Ta₂O₅: 0-5%, preferably Ta₂O₅: 0-2%; and / or Gd₂O₃: 0-5%, preferably Gd₂O₅. 3:0~2%; and / or TiO2:0~4%, preferably TiO2:0~2%; and / or RO:0~5%, preferably RO:0~2%; and / or Rn2O:0~4%, preferably Rn2O:0~2%; and / or WO3:0~6%, preferably WO3:0~4%; and / or ZnO:1~8%, preferably ZnO:2~7%; and / or Al2O3:0~3%, preferably Al2O3:0~1%; and / or Yb2O3:0~3%, preferably Yb2O3:0~1%; and / or GeO2:0~3%, preferably GeO2:0~1%; and / or clarifying agent:0~0.5%, preferably clarifying agent:0~0.2%, wherein RO is one or more of MgO, CaO, SrO, and BaO, and Rn2O is Li One or more of 2O, Na 2O, and K 2O, and one or more of Sb 2O 3, SnO, SnO 2, and CeO 2 as the clarifying agent.

[0016] Furthermore, the optical glass described herein does not contain Ta₂O₅; and / or does not contain RO; and / or does not contain Rn₂O; and / or does not contain Gd₂O₃; and / or does not contain Yb₂O₃; and / or does not contain Al₂O₃; and / or does not contain GeO₂, wherein RO is one or more of MgO, CaO, SrO, and BaO, and Rn₂O is one or more of Li₂O, Na₂O, and K₂O.

[0017] Furthermore, the refractive index nd of the optical glass is 1.82~1.89, preferably 1.83~1.88, more preferably 1.84~1.87, and the Abbe number vd is 37~44, preferably 38~43, more preferably 39~42.

[0018] Furthermore, the density ρ of the optical glass is 5.00 g / cm³ or less, preferably 4.90 g / cm³ or less, more preferably 4.80 g / cm³ or less; and / or the coefficient of thermal expansion α -30 / 70 °C is 85 × 10⁻⁷ / K or less, preferably 80 × 10⁻⁷ / K or less, more preferably 75 × 10⁻⁷ / K or less, more preferably 70 × 10⁻⁷ / K or less; and / or the water resistance stability DW is Class 2 or more, preferably Class 1; and / or the acid resistance stability DA is Class 2 or more, preferably Class 1; and / or λ 70 is 400 nm or less, preferably 395 nm or less, more preferably 390 nm or less; and / or λ 5 is 350 nm or less, preferably 345 nm or less, more preferably λ 5 is 345 nm or less. 5 is below 340nm; and / or the weather resistance CR is Class 2 or above, preferably Class 1; and / or the Knoop hardness HK is 670×10 7 Pa or above, preferably 680×10 7 Pa or above, more preferably 690×10 7 Pa or above, even more preferably 695×10 7 Pa or above; and / or the Young's modulus E is 10500×10 7 Pa or above, preferably 11000×10 7 Pa or above, more preferably 11500×10 7 Pa or above; and / or the abrasion degree FA is 75~120, preferably 80~110, more preferably 86~105; and / or the bubble degree is Grade A or above, preferably Grade A0 or above, more preferably Grade A00.

[0019] A glass preform made of the aforementioned optical glass.

[0020] An optical element made of the aforementioned optical glass or of the aforementioned glass preform.

[0021] An optical instrument comprising the aforementioned optical glass and / or the aforementioned optical elements.

[0022] The beneficial effects of this invention are: through reasonable component design, the optical glass obtained by this invention has excellent devitrification resistance and chemical stability. Implementation

[0023] The embodiments of the optical glass of the present invention will now be described in detail. However, the present invention is not limited to the embodiments described below, and appropriate modifications can be made to implement it within the scope of the purpose of the present invention. Furthermore, regarding repeated descriptions, although there are appropriate omissions, this will not limit the spirit of the invention. In the following text, the optical glass of the present invention will sometimes be simply referred to as glass.

[0024] Optical Glass

[0025] The composition range of each component in the optical glass of the present invention will be described below. In the present invention, unless otherwise specified, the content and total content of each component are expressed as a weight percentage (wt%), that is, the weight percentage of the content and total content of each component relative to the total weight of the glass material converted into oxide composition. Here, "converted into oxide composition" means that when the oxides, complex salts, and hydroxides used as raw materials for the optical glass of the present invention decompose and transform into oxides upon melting, the total amount of such oxides is taken as 100%.

[0026] Unless otherwise specified in the specific context, the numerical ranges listed in this invention include upper and lower limits, and "above" and "below" include endpoint values ​​and all integers and fractions included in the range, but are not limited to the specific values ​​listed when the range is defined. The term "and / or" as used herein is inclusive; for example, "A and / or B" means only A, or only B, or both A and B.

[0027] <Essential and Optional Components>

[0028] SiO2 has the functions of adjusting optical constants, improving the chemical stability of glass, maintaining a viscosity suitable for molten glass, reducing abrasion, and reducing corrosion to refractory materials. In this invention, the above effects are achieved by containing more than 2% SiO2, preferably more than 4%, and more preferably more than 6%. If the SiO2 content is too high, the difficulty of melting the glass increases, and the transition temperature rises. Therefore, the upper limit of the SiO2 content in this invention is 18%, preferably 15%, and more preferably 12%.

[0029] B₂O₃ can improve the melt flow properties and devitrification resistance of glass, which is beneficial for lowering the glass transition temperature. This invention achieves these effects by containing 8% or more B₂O₃, preferably 10% or more, and more preferably 12% or more. If the B₂O₃ content is too high, the chemical stability of the glass deteriorates, especially its water resistance, and the refractive index and light transmittance decrease. Therefore, the B₂O₃ content is 22% or less, preferably 20% or less, and more preferably 18% or less.

[0030] La₂O₃ is an effective component for improving the refractive index of glass, and it has a significant effect on improving the chemical stability and devitrification resistance of glass. If its content is less than 40%, it is difficult to achieve the required optical constant; if the content is higher than 60%, the glass's devitrification tendency will increase and its thermal stability will deteriorate. Therefore, the content of La₂O₃ is limited to 40-60%, preferably 43-55%, and more preferably 46-52%.

[0031] Y₂O₃ can improve the refractive index and devitrification resistance of glass, and adjust the Young's modulus of glass. This invention achieves the above effects by containing more than 3% Y₂O₃; if its content exceeds 18%, the chemical stability and weather resistance of the glass deteriorate. Therefore, the Y₂O₃ content in this invention is 3~18%, preferably 5~15%, and more preferably 7~13%.

[0032] Gd₂O₃ can improve the refractive index and chemical stability of glass, but if its content exceeds 9%, the glass's resistance to devitrification and abrasion resistance deteriorates. Therefore, the content of Gd₂O₃ is 0-9%, preferably 0-5%, and more preferably 0-2%. In some embodiments, it is even more preferable that the glass does not contain Gd₂O₃.

[0033] Yb₂O₃ is also a component that imparts high refractive index and low dispersion to glass. If its content exceeds 8%, the glass's resistance to crystallization decreases. Therefore, the content of Yb₂O₃ is 0~8%, preferably 0~3%, more preferably 0~1%, and even more preferably does not contain Yb₂O₃.

[0034] ZrO₂ can improve the viscosity, hardness, refractive index, and chemical stability of optical glass, and can also reduce the coefficient of thermal expansion of glass. However, when the ZrO₂ content is too high, the glass's resistance to devitrification decreases, the melting difficulty increases, the melting temperature rises, and inclusions appear inside the glass, leading to a decrease in light transmittance. Therefore, the ZrO₂ content in this invention is 1~15%, preferably 2~12%, and more preferably 3~10%.

[0035] TiO2 can increase the refractive index of glass, but excessive content will greatly reduce the dispersion coefficient and increase the tendency to crystallize, and may even cause the glass to become noticeably discolored. Therefore, the TiO2 content is limited to 0~6%, preferably 0~4%, and more preferably 0~2%.

[0036] Ta₂O₅ can improve the refractive index and enhance the devitrification resistance of glass. However, if its content is too high, the thermal stability of the glass decreases, the density increases, and the optical constants are difficult to control within the desired range. On the other hand, compared with other components, Ta₂O₅ is very expensive. From a practical and cost perspective, its usage should be minimized. Therefore, in this invention, the content of Ta₂O₅ is limited to 0-10%, preferably 0-5%, more preferably 0-2%, and even more preferably does not contain Ta₂O₅.

[0037] In some embodiments, controlling the ratio of the total content of Ta₂O₅ and Gd₂O₃ (Ta₂O₅+Gd₂O₃) to the content of Y₂O₃ (Ta₂O₅+Gd₂O₃) / Y₂O₃ to below 1.0 is beneficial for obtaining suitable abrasion resistance, optimizing glass density and Young's modulus, and preventing deterioration of glass chemical stability. Therefore, it is preferable that (Ta₂O₅+Gd₂O₃) / Y₂O₃ is below 1.0, more preferably (Ta₂O₅+Gd₂O₃) / Y₂O₃ is below 0.8, further preferably (Ta₂O₅+Gd₂O₃) / Y₂O₃ is below 0.5, and even more preferably (Ta₂O₅+Gd₂O₃) / Y₂O₃ is below 0.2.

[0038] Nb₂O₅ is a high-refractive-index and high-dispersion component that can improve the refractive index and devitrification resistance of glass, and reduce the coefficient of thermal expansion of glass. In this invention, the above effects are achieved by containing more than 2% Nb₂O₅, preferably with a lower limit of 3%, and more preferably with a lower limit of 5%. If the Nb₂O₅ content exceeds 15%, the thermal stability and weather resistance of the glass decrease, and the light transmittance decreases. Therefore, in this invention, the upper limit of the Nb₂O₅ content is 15%, preferably 13%, and more preferably 11%.

[0039] In some embodiments, controlling the ratio of La₂O₃ content to the total content of B₂O₃ and Nb₂O₅, B₂O₃+Nb₂O₅ (La₂O₃ / (B₂O₃+Nb₂O₅)), within the range of 1.2 to 5.0, can improve the Young's modulus of the glass and increase its bubble content. Therefore, a La₂O₃ / (B₂O₃+Nb₂O₅) ratio of 1.2 to 5.0 is preferred, and a La₂O₃ / (B₂O₃+Nb₂O₅) ratio of 1.3 to 4.0 is more preferred. Furthermore, controlling the La₂O₃ / (B₂O₃+Nb₂O₅) ratio within the range of 1.5 to 3.5 can further improve the hardness of the glass and reduce its coefficient of thermal expansion. Therefore, the preferred ratio of La₂O₃ / (B₂O₃+Nb₂O₅) is 1.5~3.5, and the preferred ratio of La₂O₃ / (B₂O₃+Nb₂O₅) is 1.7~2.7.

[0040] Alkaline earth metal oxides (RO, which is one or more of MgO, CaO, SrO, and BaO) can adjust the optical constants of glass and optimize its chemical stability. However, when the RO content is high, the glass's devitrification resistance decreases. Therefore, the RO content is limited to 0-10%, preferably 0-5%, and more preferably 0-2%. In some embodiments, it is further preferred that the glass does not contain RO.

[0041] In some embodiments, controlling the ratio of the total content of B₂O₃ and RO (B₂O₃+RO) to the content of La₂O₃ (B₂O₃+RO) / La₂O₃ within the range of 0.15 to 0.7 can improve the bubble content and weather resistance of the glass. Therefore, it is preferable that (B₂O₃+RO) / La₂O₃ is 0.15 to 0.7, more preferably (B₂O₃+RO) / La₂O₃ is 0.15 to 0.6. Furthermore, controlling (B₂O₃+RO) / La₂O₃ within the range of 0.18 to 0.5 can further improve the hardness of the glass and optimize the coefficient of thermal expansion of the glass. Therefore, it is even more preferable that (B₂O₃+RO) / La₂O₃ is 0.18 to 0.5, and even more preferably (B₂O₃+RO) / La₂O₃ is 0.2 to 0.4.

[0042] Alkali metal oxides Rn₂O (Rn₂O is one or more of Li₂O, Na₂O, and K₂O) can lower the glass transition temperature, adjust the optical constant and high-temperature viscosity of the glass, and improve the glass's meltability. However, when its content is high, the glass's resistance to devitrification and chemical stability decrease. Therefore, in this invention, the Rn₂O content is 0-8%, preferably 0-4%, and more preferably 0-2%. In some embodiments, it is further preferred that Rn₂O is not present.

[0043] ZnO can adjust the refractive index and dispersion of glass, and reduce its high-temperature viscosity and transition temperature. However, if the ZnO content is too high, glass forming becomes more difficult, and its resistance to crystallization deteriorates. Therefore, the ZnO content is 0-10%, preferably 1-8%, and more preferably 2-7%.

[0044] In some embodiments, controlling the ratio of the total content of ZnO and Ta₂O₅ (ZnO+Ta₂O₅) to the content of Nb₂O₅ (ZnO+Ta₂O₅) / Nb₂O₅ to below 2.0 is beneficial to improving the chemical stability and light transmittance of the glass. Therefore, it is preferable that (ZnO+Ta₂O₅) / Nb₂O₅ is below 2.0, more preferably below 1.5. Furthermore, controlling (ZnO+Ta₂O₅) / Nb₂O₅ to below 1.0 can further improve the Young's modulus and bubble content of the glass. Therefore, it is even more preferable that (ZnO+Ta₂O₅) / Nb₂O₅ is below 1.0, and even more preferably below 0.1 to 0.8.

[0045] In some embodiments, by controlling the ratio of the total content of Gd₂O₃ and ZnO (Gd₂O₃+ZnO) to the content of Y₂O₃ (Gd₂O₃+ZnO) / Y₂O₃ to below 2.0, the coefficient of thermal expansion of the glass can be reduced, and the abrasion resistance of the glass can be optimized. Therefore, it is preferable that (Gd₂O₃+ZnO) / Y₂O₃ is below 2.0, and more preferably (Gd₂O₃+ZnO) / Y₂O₃ is below 1.5. Furthermore, controlling (Gd₂O₃+ZnO) / Y₂O₃ to below 1.0 makes it easier for the glass to obtain a suitable Young's modulus and prevents a decrease in glass hardness. Therefore, it is further preferred that (Gd₂O₃+ZnO) / Y₂O₃ be 1.0 or less, and even more preferably (Gd₂O₃+ZnO) / Y₂O₃ be 0.8 or less.

[0046] WO3 can improve the refractive index and mechanical strength of glass. However, if the WO3 content exceeds 8%, the thermal stability and devitrification resistance of the glass decrease. Therefore, the WO3 content is 0-8%, preferably 0-6%, and more preferably 0-4%.

[0047] In some embodiments, controlling the ratio of the total content of Gd₂O₃, Ta₂O₅, and WO₃ (Gd₂O₃+Ta₂O₅+WO₃) to the content of La₂O₃ (Gd₂O₃+Ta₂O₅+WO₃) / La₂O₃ to below 0.5 can reduce the density of the glass and improve its light transmittance. Therefore, it is preferable that (Gd₂O₃+Ta₂O₅+WO₃) / La₂O₃ is below 0.5, and more preferably (Gd₂O₃+Ta₂O₅+WO₃) / La₂O₃ is below 0.4. Furthermore, controlling (Gd₂O₃+Ta₂O₅+WO₃) / La₂O₃ to below 0.3 can further optimize the abrasion resistance and coefficient of thermal expansion of the glass. Therefore, it is further preferred that (Gd₂O₃+Ta₂O₅+WO₃) / La₂O₃ be 0.3 or less, and even more preferably (Gd₂O₃+Ta₂O₅+WO₃) / La₂O₃ be 0.2 or less.

[0048] In some embodiments, controlling the ratio of the total content of ZnO and WO3 (ZnO+WO3) to the content of Nb2O5 (ZnO+WO3) / Nb2O5 to below 3.0 can improve the weather resistance of the glass and reduce its density. Therefore, it is preferable that (ZnO+WO3) / Nb2O5 is below 3.0, more preferably below 2.0, and even more preferably below 1.5. Furthermore, controlling (ZnO+WO3) / Nb2O5 within the range of 0.2 to 1.0 can further optimize the hardness of the glass. Therefore, it is even more preferable that (ZnO+WO3) / Nb2O5 is 0.2 to 1.0.

[0049] Al₂O₃ can improve the chemical stability of glass, but when its content exceeds 5%, the meltability and light transmittance of the glass deteriorate. Therefore, in this invention, the content of Al₂O₃ is 0-5%, preferably 0-3%, and more preferably 0-1%. In some embodiments, it is further preferred that the glass does not contain Al₂O₃.

[0050] GeO2 improves refractive index and devitrification resistance, but excessive content reduces the chemical stability of the glass. Furthermore, GeO2 is very expensive compared to other components, and its usage should be minimized from a practical and cost-effective perspective. Therefore, the GeO2 content in this invention is limited to 0-5%, preferably 0-3%, more preferably 0-1%, and even more preferably does not contain GeO2.

[0051] In this invention, one or more components selected from Sb₂O₃, SnO, SnO₂, and CeO₂ are used as clarifying agents (0-1%) to improve the clarification effect and bubble content of the glass. Preferably, the clarifying agent content is 0-0.5%, more preferably 0-0.2%. Because the optical glass of this invention has a reasonable design in terms of component types and content, resulting in excellent bubble content, it is further preferred in some embodiments to be free of clarifying agents. When the Sb₂O₃ content exceeds 1%, the glass tends to have reduced clarification performance. Simultaneously, its strong oxidizing effect promotes the corrosion of platinum or platinum alloy vessels used in the molten glass and the deterioration of the forming mold. Therefore, in this invention, the Sb₂O₃ content is preferably 0-1%, more preferably 0-0.5%, further preferably 0-0.2%, and even more preferably free of Sb₂O₃. SnO and SnO2 can also be used as clarifying agents, but when their content exceeds 1%, the tendency for glass coloring increases. Alternatively, when the glass is heated, softened, and then molded, Sn can become the starting point for crystal nucleation, leading to a tendency for devitrification. Therefore, the SnO2 content of this invention is preferably 0-1%, more preferably 0-0.5%, further preferably 0-0.2%, and even more preferably free of SnO2. The SnO content is preferably 0-1%, more preferably 0-0.5%, further preferably 0-0.2%, and even more preferably free of SnO. The role and content ratio of CeO2 are the same as those of SnO2, and its content is preferably 0-1%, more preferably 0-0.5%, further preferably 0-0.2%, and even more preferably free of CeO2.

[0052] <Components that should not be present>

[0053] In the glass of this invention, even if oxides of transition metals such as V, Cr, Mn, Fe, Co, Ni, Cu, Ag, and Mo are present in small amounts, either alone or in combination, the glass will be colored and absorb at specific wavelengths in the visible light region, thereby weakening the property of this invention to improve visible light transmittance. Therefore, it is preferable that the glass does not contain these oxides, especially for optical glass where transmittance in the visible light region is required.

[0054] Oxides of Th, Cd, Tl, Os, Be, and Se have been increasingly subject to controlled use in recent years due to their status as hazardous chemicals. Environmental protection measures are essential not only in glass manufacturing but also in processing and post-product disposal. Therefore, given the importance of environmental impact, it is preferable to avoid the presence of these substances, except where their contamination is unavoidable. As a result, the optical glass becomes virtually free of pollutants. Therefore, the optical glass of this invention can be manufactured, processed, and disposed of even without special environmental countermeasures.

[0055] To achieve environmental friendliness, the optical glass of the present invention preferably does not contain As₂O₃ and PbO.

[0056] The terms "not containing" or "0%" as used herein mean that the compound, molecule, or element was not intentionally added to the optical glass of this invention as a raw material; however, as raw materials and / or equipment used in the production of optical glass, there may be certain impurities or components that are not intentionally added, which may be present in small or trace amounts in the final optical glass, and such cases are also within the scope of protection of this patent.

[0057] The performance of the optical glass of the present invention will now be described.

[0058] <Refractive Index and Abbe Number>

[0059] The refractive index (nd) and Abbe number (νd) of optical glass are tested according to the method specified in GB / T 7962.1—2010.

[0060] In some embodiments, the lower limit of the refractive index (nd) of the optical glass of the present invention is 1.82, preferably 1.83, and more preferably 1.84.

[0061] In some embodiments, the upper limit of the refractive index (nd) of the optical glass of the present invention is 1.89, preferably 1.88, and more preferably 1.87.

[0062] In some embodiments, the lower limit of the Abbe number (νd) of the optical glass of the present invention is 37, preferably 38, and more preferably 39.

[0063] In some embodiments, the upper limit of the Abbe number (νd) of the optical glass of the present invention is 44, preferably 43, and more preferably 42.

[0064] <Density>

[0065] The density (ρ) of optical glass was tested according to the method specified in GB / T7962.20-2010.

[0066] In some embodiments, the density (ρ) of the optical glass of the present invention is 5.00 g / cm³ or less, preferably 4.90 g / cm³ or less, and more preferably 4.80 g / cm³ or less.

[0067] <Coefficient of thermal expansion>

[0068] The thermal expansion coefficient (α -30 / 70 ℃) of optical glass is tested according to the method specified in GB / T7962.16-2010 for temperatures ranging from -30 to 70℃.

[0069] In some embodiments, the coefficient of thermal expansion (α -30 / 70 °C) of the optical glass of the present invention is 85 × 10⁻⁷ / K or less, preferably 80 × 10⁻⁷ / K or less, more preferably 75 × 10⁻⁷ / K or less, and even more preferably 70 × 10⁻⁷ / K or less.

[0070] <Stability under water resistance>

[0071] The water resistance stability (DW) of optical glass (powder method) was tested according to the method specified in GB / T 17129.

[0072] In some embodiments, the water resistance stability (DW) of the optical glass of the present invention is Class 2 or above, preferably Class 1.

[0073] <Stability under acid conditions>

[0074] The acid resistance stability (DA) of optical glass (powder method) was tested according to the method specified in GB / T 17129.

[0075] In some embodiments, the acid resistance stability (DA) of the optical glass of the present invention is Class 2 or above, preferably Class 1.

[0076] <shading>

[0077] The short-wavelength transmission spectral characteristics of the glass of this invention are represented by tinting strength (λ70 and λ5). λ70 refers to the wavelength corresponding to a glass transmittance of 70%. λ70 is measured using glass with two parallel and optically polished opposing planes of a thickness of 10 ± 0.1 mm. The spectral transmittance in the wavelength range from 280 nm to 700 nm is measured, and the wavelength exhibiting 70% transmittance is recorded. Spectroscopic transmittance, or transmittance, is the quantity expressed as I out / I in when light of intensity I in is incident perpendicularly to the aforementioned surface of the glass, passes through the glass, and exits from a plane as light of intensity I out. It also includes the transmittance due to surface reflection loss on the aforementioned surface of the glass. The higher the refractive index of the glass, the greater the surface reflection loss. Therefore, in high-refractive-index glasses, a small value of λ70 means that the glass itself has very little tinting strength and high light transmittance.

[0078] In some embodiments, the λ 70 of the optical glass of the present invention is 400 nm or less, preferably 395 nm or less, and more preferably 390 nm or less.

[0079] In some embodiments, the λ5 of the optical glass of the present invention is 350 nm or less, preferably 345 nm or less, and more preferably 340 nm or less.

[0080] <Weather resistance>

[0081] The weather resistance (CR) test method for optical glass is as follows: The sample is placed in a test chamber with a relative humidity of 90% and saturated water vapor, and the temperature is alternately cyclical every 1 hour at 40-50℃, for 15 cycles. Weather resistance is classified according to the change in turbidity before and after the sample placement. The weather resistance classification is shown in Table 1. [Table 1] category 1 2 3 4 a b c Increase in turbidity ΔH (%) <0.3 0.3~1.0 Version 1.0~2.0 2.0~4.0 4.0~6.0 ≥6.0

[0082] In some embodiments, the weather resistance (CR) of the optical glass of the present invention is Class 2 or above, preferably Class 1.

[0083] Knoop Hardness

[0084] The Knoop hardness (HK) of optical glass was tested according to the test method specified in GB / T7962.18-2010.

[0085] In some embodiments, the Knoop hardness (HK) of the optical glass of the present invention is 670 × 10⁷ Pa or more, preferably 680 × 10⁷ Pa or more, more preferably 690 × 10⁷ Pa or more, and even more preferably 695 × 10⁷ Pa or more.

[0086] Young's Modulus

[0087] Young's modulus (E) is obtained by ultrasonic testing of longitudinal and transverse wave velocities, and then calculated using the following formula.

[0088]

[0089] G=VS 2ρ

[0090] In the formula: E is Young's modulus, Pa;

[0091] G is the shear modulus, in Pa;

[0092] VT is the transverse wave velocity, in m / s;

[0093] VS represents the longitudinal wave velocity, in m / s;

[0094] ρ is the density of glass, in g / cm³.

[0095] In some embodiments, the Young's modulus (E) of the optical glass of the present invention is 10500×10 7 Pa or more, preferably 11000×10 7 Pa or more, and more preferably 11500×10 7 Pa or more.

[0096] <wear level>

[0097] The abrasion factor (FA) of optical glass refers to the ratio of the abrasion amount of the sample to the abrasion amount (volume) of the standard sample (H-K9 glass) under identical conditions, multiplied by 100. The formula is as follows:

[0098] FA=V / V 0×100=(W / ρ) / ( W 0 / ρ 0)×100

[0099] Where: V—volume wear of the tested sample;

[0100] V0—Volume wear of the standard sample;

[0101] W—Abrasion loss of the tested sample;

[0102] W0—Standard sample quality wear amount;

[0103] ρ—Density of the sample being measured;

[0104] ρ0 — density of standard sample.

[0105] In some embodiments, the lower limit of the abrasion degree (FA) of the optical glass of the present invention is 75, preferably 80, and more preferably 86.

[0106] In some embodiments, the maximum abrasion factor (FA) of the optical glass of the present invention is 120, preferably 110, and more preferably 105.

[0107] <Effervescence>

[0108] The bubble content of optical glass shall be tested according to the method specified in GB / T7962.8-2010.

[0109] In some embodiments, the bubble degree of the optical glass of the present invention is grade A or above, preferably grade A0 or above, and more preferably grade A00.

[0110] [Manufacturing methods for optical glass]

[0111] The manufacturing method of the optical glass of this invention is as follows: The glass of this invention is produced using conventional raw materials and processes, including but not limited to using oxides, hydroxides, complex salts (such as carbonates, nitrates, sulfates, etc.), boric acid, etc. as raw materials. After the raw materials are prepared according to conventional methods, the prepared furnace charge is put into a melting furnace (such as a platinum or platinum alloy crucible) at 1200~1500℃ for melting. After clarification and homogenization, a homogeneous molten glass without bubbles and undissolved substances is obtained. This molten glass is then cast in a mold and annealed. Those skilled in the art can appropriately select raw materials, process methods, and process parameters according to actual needs.

[0112] [Glass preforms and optical components]

[0113] Glass preforms can be manufactured from the produced optical glass using methods such as direct drop forming, grinding, or hot pressing. Specifically, glass preforms can be manufactured by directly and precisely drop-forming molten optical glass into precision glass preforms, or by machining such as grinding and polishing, or by hot pressing a preform made from optical glass for compression molding followed by grinding. It should be noted that the methods for preparing glass preforms are not limited to the methods described above.

[0114] As described above, the optical glass of the present invention is useful for various optical components and optical designs. It is particularly preferred to form a preform from the optical glass of the present invention, and to use the preform for hot pressing, precision stamping, etc., to manufacture optical components such as lenses and prisms.

[0115] Both the glass preform and the optical element of the present invention are formed from the optical glass described above. The glass preform of the present invention possesses the excellent properties of optical glass; the optical element of the present invention possesses the excellent properties of optical glass, and can provide various optical elements such as lenses and prisms with high optical value.

[0116] Examples of lenses include concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, plano-concave lenses, and so on, where the lens surface is spherical or aspherical.

[0117] [Optical Instruments]

[0118] The optical elements formed by the optical glass of the present invention can be used to manufacture optical instruments such as photographic equipment, video equipment, projection equipment, display devices, vehicle-mounted equipment, and monitoring equipment.

[0119] Example

[0120] <Example of Optical Glass>

[0121] To further illustrate and explain the technical solution of the present invention, the following non-limiting embodiments are provided.

[0122] In this embodiment, optical glass with the composition shown in Tables 2 to 4 was obtained using the optical glass manufacturing method described above. Furthermore, the properties of each glass were measured using the testing method described in this invention, and the measurement results are shown in Tables 2 to 4. [Table 2] Example (wt%) 1# 2# 3# 4# 5# 6# 7# 8# SiO2 10.23 13.5 15.2 8.52 3.75 5.3 4.73 6.72 B2O3 18.6 9.45 10.43 17.24 21.05 11.84 17.35 15.23 La2O3 46.37 45.75 46.71 47.6 47.11 42.82 46.8 43.98 Y2O3 5.25 4.65 8.24 13.32 6.33 12.5 15.4 7.2 Gd2O3 0 2.6 0 0 1.5 0 0.55 0 Yb2O3 0 0 0 0 0 0 0 0 ZrO2 2.45 11.5 13.24 3.7 4.45 1.54 5.5 10.25 Nb2O5 13.2 8.23 3.35 7.12 5.58 12.4 6.54 9.2 TiO2 0 0 0 0.1 0 0 0.3 0 Ta2O5 0 1.2 0 0 0.6 0.8 0 2.1 MgO 1 0 0 0.8 0 0 0 0 High 0 0 1.4 0.6 0 2.5 0 0 SrO 0 0 0 0 0 0 0 0 Bag 0 2.2 0 0 1.6 0 0 0 Li2O 0 0 0.6 0 0 1 0 0 Na2O 0 0 0 0 0 0.5 0 0 K2O 0 0 0 0 0.8 0 0 1 WO3 1.3 0 0.5 0.8 0 5.2 0 0 ZnO 1.6 0.82 0.33 0 7.23 3.5 2.63 4.32 Al2O3 0 0 0 0 0 0 0 0 GeO2 0 0 0 0 0 0 0 0 Sb2O3 0 0.1 0 0 0 0.1 0.2 0 SnO 0 0 0 0 0 0 0 0 SnO2 0 0 0 0.2 0 0 0 0 CeO2 0 0 0 0 0 0 0 [[ID=5__0]] 0 Total 100 100 100 100 100 100 100 100 (ZnO + Ta2O5) / Nb2O5 0.121 0.245 0.099 0 [[ID=8__1]] 1.403 0.347 0.402 0.698 (Gd2O3 + Ta2O5 + WO3) / La2O3 0.028 0.083 0.011 0.017 0.045 0.14 0.012 0.048 <__ (Ta2O5 + Gd2O3) / Y2O3 0 0.817 0 0 0.332 0.064 0.036 0.292 La2O3 / (B2O3+Nb2O5) 1.458 2.588 3.39 1.954 1.769 1.767 1.959 1.8 (ZnO+WO3) / Nb2O5 0.22 0.1 0.248 0.112 1.296 0.702 0.402 0.47 (B2O3+RO) / La2O3 0.423 0.255 0.253 0.392 0.481 0.335 0.371 0.347 (Gd2O3+ZnO) / Y2O3 0.305 0.735 0.04 0 1.379 0.28 0.206 0.6 nd 1.8648 1.8836 1.8655 1.8373 1.8225 1.8428 1.8467 1.8756 νd 37.35 39.27 43.26 39.85 43.15 37.83 42.56 39.78 DW Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 DA Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 CR Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 HK(×107Pa) 697 694 695 698 688 702 703 701 FA 93 85 94 92 106 95 95 93 E(×107Pa) 11676 11745 11342 11858 11273 12437 12520 12438 ρ(g / cm3) 4.75 4.83 4.73 4.80 4.82 4.72 4.73 4.75 λ70(nm) 382 384 388 390 387 380 377 382 λ5(nm) 331 333 338 340 336 328 327 330 Bubble density (grade) A0 A00 A0 A00 A0 A00 A00 A00 α-30 / 70℃ (×10-7 / K) 73 66 70 65 72 63 64 65 [Table 3] Example (wt%) 9# 10# 11# 12# 13# 14# 15# 16# SiO2 8.24 7.92 9.03 9.44 11.25 12.24 8.43 9.15 B2O3 14.75 12.24 13.54 19.2 20.35 16.38 14.82 13.64 La2O3 50.67 44.32 43.88 51.87 41.03 41.67 49.28 49.08 Y2O3 3.5 9.44 10.24 4.1 3.2 11.54 9.32 10.04 Gd2O3 0 0 0 0 0 0 0 0 Yb2O3 0 0 0 0 0 0 0 0 ZrO2 9.32 6.16 7.35 4.29 8.18 5.03 6.43 5.26 Nb2O5 10.42 11.22 7.43 8.04 8.32 9.12 6.54 6.8 TiO2 1 0 0.5 0 2.2 0 0 0.3 Ta2O5 0 1.3 0 0 0 0 0 0 MgO 0 0 0 0 0 0 0 0 High 0 0 0 0 0 0 0 0 SrO 0 0 0 0 0 0 0 0 Bag 0 1.2 0 0 0 0 0 0 Li2O 0 0 0 0 0 0 0 0 Na2O 0 0 0 0 0 0 0 0 K2O 0 0 0 0 0 0 0 0 WO3 2.1 0 2.5 0 1.2 0.6 1.4 0 ZnO 0 6.2 5.53 3.06 4.17 3.42 3.58 4.63 Al2O3 0 0 0 0 0 0 0 1.1 GeO2 0 0 0 0 0 0 0 0 Sb2O3 0 0 0 0 0.1 0 0.2 0 SnO 0 0 0 0 0 0 0 0 SnO2 0 0 0 0 0 0 0 0 CeO2 0 0 0 0 0 0 0 0 Total 100 100 100 100 100 100 100 100 (ZnO + Ta2O5) / Nb2O5 0 0.668 0.744 0.381 0.501 0.375 0.547 0.681 (Gd2O3 + Ta2O5 + WO3) / La2O3 0.041 0.029 0.057 0 0.029 0.014 0.028 0 (Ta2O5 + Gd2O3) / Y2O3 0 0.138 0 0 0 0 0 0 La2O3 / (B2O3 + Nb2O5) 2.013 1.889 2.093 1.904 1.431 1.634 2.307 2.401 (ZnO + WO3) / Nb2O5 0.202 0.553 1.081 0.381 0.645 0.441 0.761 0.681 (B2O3 + RO) / La2O3 0.291 0.303 0.309 0.37 0.496 0.393 0.301 0.278 (Gd2O3 + ZnO) / Y2O3 0 0.657 0.54 0.746 1.303 0.296 0.384 0.461 nd 1.8783 1.8475 1.8633 1.8382 1.8553 1.8612 1.8524 1.8534 νd 38.86 38.24 42.16 41.25 40.74 39.66 40.27 41.04 DW Category 1 Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 DA Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 CR Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 HK(×107Pa) 703 705 693 705 690 704 702 705 FA 94 98 92 93 105 95 94 92 E(×107Pa) 11745 12510 12488 12523 11327 11784 12356 12452 ρ(g / cm3) 4.69 4.70 4.77 4.71 4.73 4.70 4.71 4.68 λ70(nm) 386 376 377 380 381 380 381 383 λ5(nm) 335 325 328 331 330 330 330 332 Bubble density (grade) A 00 A 00 A 00 A 00 A 0 A 00 A 00 A 00 α-30 / 70℃ (×10-7 / K) 62 60 62 65 75 63 64 62 [Table 4] Example (wt%) 17# 18# 19# 20# twenty one# twenty two# twenty three# twenty four# SiO2 9.42 8.74 7.83 8.28 6.32 10.23 9.83 8.75 B2O3 12.88 15.53 14.27 15.03 16.62 15.83 14.82 15.82 La2O3 47.87 47.77 47.08 44.64 47.52 46.97 46.48 49.15 Y2O3 8.54 9.32 11.15 10.64 10.38 9.24 7.34 8.5 Gd2O3 0 0 0 0 0 0 0 0 Yb2O3 0 0 0 0 0 0 0 0 ZrO2 8.05 5.22 4.85 6.37 6.25 5.43 4.76 6.35 Nb2O5 7.13 7.88 8.5 8.17 7.83 7.45 6.62 7.38 TiO2 0.8 0 0 1.1 0 0 1.5 0 Ta2O5 0 0 0 0 0 0 0 0 MgO 0 0 0 0 0 0 0 0 CaO 0 0 0 0 0 0 0 0 SrO 0 0 0 0 0 0 0 0 BaO 0 0 0 0 0 0 0 0 Li2O 0 0 0 0 0 0 0 0 Na2O 0 0 0 0 0 0 0 0 K2O 0 0 0 0 0 0 0 0 WO3 0.5 0 1.5 0 1.7 0.2 3.4 0 ZnO 4.81 5.54 4.82 5.77 3.38 4.65 5.25 4.05 Al2O3 0 0 0 0 0 0 0 0 SceneO2 0 0 0 0 0 0 0 0 Sb2O3 0 0 0 0 0 0 0 0 SnO 0 0 0 0 0 0 0 0 SnO2 0 0 0 0 0 0 0 0 CeO2 0 0 0 0 0 0 0 0 total 100 100 100 100 100 100 100 100 (ZnO+Ta2O5) / Nb2O5 0.675 0.703 0.567 0.706 0.432 0.624 0.793 0.549 (Gd2O3+Ta2O5+WO3) / La2O3 0.01 0 0.032 0 0.036 0.004 0.073 0 (Ta2O5+Gd2O3) / Y2O3 0 0 0 0 0 0 0 0 La2O3 / (B2O3+Nb2O5) 2.392 2.041 2.068 1.924 1.944 2.018 2.168 2.119 (ZnO+WO3) / Nb2O5 0.745 0.703 0.744 0.706 0.649 0.651 1.307 0.549 (B2O3+RO) / La2O3 0.269 0.325 0.303 0.337 0.35 0.337 0.319 0.322 (Gd₂O₃+ZnO) / Y₂O₃ 0.563 0.594 0.432 0.542 0.326 0.503 0.715 0.476 nd 1.8522 1.8518 1.8512 1.8489 1.8515 1.8478 1.8521 1.8526 νd 40.88 40.62 41.21 40.54 40.26 41.38 40.72 40.57 DW Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 DA Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 CR Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 Class 1 HK(×107Pa) 708 704 710 705 703 709 710 704 FA 91 95 94 96 95 93 95 94 E(×107Pa) 12507 12388 12463 12645 12482 12433 12684 12450 ρ(g / cm3) 4.67 4.71 4.72 4.74 4.70 4.72 4.78 4.71 λ70(nm) 382 380 378 377 380 379 378 376 λ5(nm) 330 328 328 327 331 330 327 326 Bubble density (grade) A 00 A 00 A 00 A 00 A 00 A 00 A 00 A 00 α-30 / 70℃ (×10-7 / K) 64 65 63 66 65 67 63 64

[0123] <Example of Glass Prefabricated Components>

[0124] The glass obtained from optical glass Examples 1 to 24# is used to manufacture preforms of various lenses and prisms, such as concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, and plano-concave lenses, by means of grinding, hot pressing, precision stamping, or other molding methods.

[0125] <Optical Component Examples>

[0126] Annealing the preforms obtained from the above glass preform examples reduces the internal stress of the glass while fine-tuning the refractive index, so that the optical properties such as the refractive index reach the required values.

[0127] Next, the prefabricated parts are ground and polished to produce various lenses and prisms, such as concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, and plano-concave lenses. Anti-reflective coatings can also be applied to the surface of the resulting optical elements.

[0128] <Examples of Optical Instruments>

[0129] The optical elements obtained from the above-described optical element embodiments can be used, through optical design, to form optical components or optical elements by using one or more optical elements. They can be used in, for example, imaging devices, sensors, microscopes, medical technology, digital projection, communications, optical communication technology / information transmission, optics / lighting in the automotive field, photolithography, excimer lasers, wafers, computer wafers, and integrated circuits and electronic devices that include such circuits and wafers.

Claims

1. An optical glass, wherein, Its composition, expressed as a weight percentage, contains: SiO2: 2–18%; B2O3: 8–22%; La2O3: 40–60%; Y2O3: 3–18%; ZrO2: 1–15%; Nb2O5: 2–15%; ZnO: 2–10%, (ZnO+WO3) / Nb2O5 is 0.2–3.0, and (ZnO+Ta2O5) / Nb2O5 is 0.375–2.

0.

2. The optical glass as claimed in claim 1, wherein, Its components, expressed as a weight percentage, also contain: Ta2O5: 0–10%; and / or Gd2O3: 0–9%; and / or TiO2: 0–6%; and / or RO: 0–10%; and / or Rn2O: 0–8%; and / or WO3: 0–8%; and / or Al2O3: 0–5%; and / or Yb2O3: 0–8%; and / or GeO2: 0–5%; and / or clarifying agent: 0–1%, wherein the RO is one or more of MgO, CaO, SrO, and BaO, the Rn2O is one or more of Li2O, Na2O, and K2O, and the clarifying agent is one or more of Sb2O3, SnO, SnO2, and CeO2.

3. An optical glass, wherein, Its composition, expressed as a weight percentage, is as follows: SiO2: 2–18%; B2O3: 8–22%; La2O3: 40–55%; Y2O3: 3–18%; ZrO2: 1–15%; Nb2O5: 2–15%; Ta2O5: 0–10%; Gd2O3: 0–9%. TiO2: 0~6%; RO: 0~10%; Rn2O: 0~8%; WO3: 0-8%; ZnO: 2-10%; Al2O3: 0-5%; Yb2O3: 0-8%; GeO2: 0-5%; clarifying agent: 0-1% composition, (ZnO+WO3) / Nb2O5 is 0.2-3.0, (ZnO+Ta2O5) / Nb2O5 is 0.375-2.0, wherein RO is one or more of MgO, CaO, SrO, and BaO, Rn2O is one or more of Li2O, Na2O, and K2O, and the clarifying agent is one or more of Sb2O3, SnO, SnO2, and CeO2.

4. The optical glass as claimed in any one of claims 1 to 3, wherein, Its components are expressed as weight percentages and satisfy one or more of the following five conditions: 1) (Gd2O3+Ta2O5+WO3) / La2O3 is 0.5 or less; 2) (Ta2O5+Gd2O3) / Y2O3 is 1.0 or less; 3) La2O3 / (B2O3+Nb2O5) is 1.2 to 5.0; 4) (B2O3+RO) / La2O3 is 0.15 to 0.7; 5) (Gd2O3+ZnO) / Y2O3 is 2.0 or less, wherein RO is one or more of MgO, CaO, SrO, and BaO.

5. The optical glass as claimed in any one of claims 1 to 3, wherein, Its components are expressed as weight percentages and satisfy one or more of the following seven conditions: 1) (ZnO+Ta2O5) / Nb2O5 is 0.375~1.5; 2) (Gd2O3+Ta2O5+WO3) / La2O3 is 0.4 or less; 3) (Ta2O5+Gd2O3) / Y2O3 is 0.8 or less; 4) La2O3 / (B2O3+Nb2O5) is 1.3~4.0; 5) (ZnO+WO3) / Nb2O5 is 0.2~2.0; 6) (B2O3+RO) / La2O3 is 0.15~0.6; 7) (Gd2O3+ZnO) / Y2O3 is 1.5 or less, wherein RO is one or more of MgO, CaO, SrO, and BaO.

6. The optical glass as claimed in any one of claims 1 to 3, wherein, Its components are expressed as weight percentages and satisfy one or more of the following seven conditions: 1) (ZnO+Ta2O5) / Nb2O5 is 0.375~1.0; 2) (Gd2O3+Ta2O5+WO3) / La2O3 is 0.3 or less; 3) (Ta2O5+Gd2O3) / Y2O3 is 0.5 or less; 4) La2O3 / (B2O3+Nb2O5) is 1.5~3.5; 5) (ZnO+WO3) / Nb2O5 is 0.2~1.5; 6) (B2O3+RO) / La2O3 is 0.18~0.5; 7) (Gd2O3+ZnO) / Y2O3 is 1.0 or less, wherein RO is one or more of MgO, CaO, SrO, and BaO.

7. The optical glass as claimed in any one of claims 1 to 3, wherein, Its components are expressed as weight percentages and satisfy one or more of the following seven conditions: 1) (ZnO+Ta2O5) / Nb2O5 is 0.375 to 0.8; 2) (Gd2O3+Ta2O5+WO3) / La2O3 is 0.2 or less; 3) (Ta2O5+Gd2O3) / Y2O3 is 0.2 or less; 4) La2O3 / (B2O3+Nb2O5) is 1.7 to 2.7; 5) (ZnO+WO3) / Nb2O5 is 0.2 to 1.0; 6) (B2O3+RO) / La2O3 is 0.2 to 0.4; 7) (Gd2O3+ZnO) / Y2O3 is 0.8 or less, wherein RO is one or more of MgO, CaO, SrO, and BaO.

8. The optical glass as claimed in any one of claims 1 to 3, wherein, Its components are expressed as a weight percentage. Wherein: SiO2: 4-15%; and / or B2O3: 10-20%; and / or La2O3: 43-55%; and / or Y2O3: 5-15%; and / or ZrO2: 2-12%; and / or Nb2O5: 3-13%; and / or Ta2O5: 0-5%; and / or Gd2O3: 0-5%; and / or TiO2: 0-4%; and / or RO: 0-5%; and / or Rn2O: 0-4%; and / or WO3: 0–6%; and / or ZnO: 2–8%; and / or Al2O3: 0–3%; and / or Yb2O3: 0–3%; and / or GeO2: 0–3%; and / or clarifying agent: 0–0.5%, wherein RO is one or more of MgO, CaO, SrO, and BaO, Rn2O is one or more of Li2O, Na2O, and K2O, and the clarifying agent is one or more of Sb2O3, SnO, SnO2, and CeO2.

9. The optical glass as claimed in any one of claims 1 to 3, wherein, Its components are expressed as a weight percentage. Wherein: SiO2: 6-12%; and / or B2O3: 12-18%; and / or La2O3: 46-52%; and / or Y2O3: 7-13%; and / or ZrO2: 3-10%; and / or Nb2O5: 5-11%; and / or Ta2O5: 0-2%; and / or Gd2O3: 0-2%; and / or TiO2: 0-2%; and / or RO: 0-2%; and / or Rn2O: 0-2%; and / or WO3: 0–4%; and / or ZnO: 2–7%; and / or Al2O3: 0–1%; and / or Yb2O3: 0–1%; and / or GeO2: 0–1%; and / or clarifying agent: 0–0.2%, wherein RO is one or more of MgO, CaO, SrO, and BaO, Rn2O is one or more of Li2O, Na2O, and K2O, and the clarifying agent is one or more of Sb2O3, SnO, SnO2, and CeO2.

10. The optical glass as claimed in any one of claims 1 to 3, wherein, Its components do not contain Ta2O5; and / or RO; and / or Rn2O; and / or Gd2O3; and / or Yb2O3; and / or Al2O3; and / or GeO2, wherein RO is one or more of MgO, CaO, SrO, and BaO, and Rn2O is one or more of Li2O, Na2O, and K2O.

11. The optical glass as claimed in any one of claims 1 to 3, wherein, The optical glass has a refractive index nd of 1.82 to 1.89 and an Abbe number vd of 37 to 44.

12. The optical glass as claimed in any one of claims 1 to 3, wherein, The optical glass has a refractive index nd of 1.84 to 1.87 and an Abbe number vd of 39 to 42.

13. The optical glass as claimed in any one of claims 1 to 3, wherein, The optical glass has the following properties: density ρ is less than 5.00 g / cm3; and / or coefficient of thermal expansion α-30 / 70℃ is less than 85×10-7 / K; and / or water resistance stability DW is Class 2 or above; and / or acid resistance stability DA is Class 2 or above; and / or λ70 is less than 400 nm; and / or λ5 is less than 350 nm; and / or weather resistance CR is Class 2 or above; and / or Knoop hardness HK is 670×107 Pa or above; and / or Young's modulus E is 10500×107 Pa or above; and / or abrasion degree FA is 75-120; and / or bubble degree is Grade A or above.

14. The optical glass as claimed in any one of claims 1 to 3, wherein, The optical glass has the following properties: density ρ below 4.80 g / cm³; thermal expansion coefficient α-30 / 70℃ below 70×10⁻⁷ / K; water resistance stability DW Class 1; acid resistance stability DA Class 1; λ70 below 390 nm; λ5 below 340 nm; weather resistance CR Class 1; Knoop hardness HK above 690×10⁷ Pa; Young's modulus E above 11500×10⁷ Pa; abrasion resistance FA 86-105; and bubble density A00 grade.

15. A glass preform, wherein, It is made of optical glass as described in any one of claims 1 to 14.

16. An optical element, wherein, It is made of optical glass as described in any one of claims 1 to 14, or of glass preform as described in claim 15.

17. An optical instrument, wherein, It contains optical glass as described in any one of claims 1 to 14, and / or contains optical elements as described in claim 16.