Optical glass

Abstract

To provide optical glass which has a desired refractive index and Abbe number and also has negative anomalous dispersion.SOLUTION: Provided is optical glass which comprises the following components in percentage by weight: SiO2: 4-11%; B2O3: 8-15%; La2O3: greater than 45% but 55% or less; Gd2O3: 2-9.5%; Y2O3: 4-10%; ZrO2: 3-10%; Nb2O5: 5-12%; TiO2: 0.1-5%; Al2O3: greater than 0 but 4% or less, wherein (La2O3+Y2O3) / (Nb2O5+ZrO2)=2.5-6.5.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This application relates to optical glasses, and more particularly to optical glasses having negative anomalous dispersion. [Background technology]

[0002] In recent years, with the rapid development of fields such as photoelectric information, digital displays, surveillance security, and in-vehicle imaging, there has been an increasing demand for smaller, lighter, and higher-performance optical elements used in optical systems. For the same radius of curvature, a glass with a higher refractive index can provide a larger imaging field of view, which is advantageous for reducing the number of optical elements in optical equipment. As optical equipment becomes increasingly smaller, the demand for high-refractive-index glasses is becoming increasingly prominent. Optical glasses with refractive indices between 1.86 and 1.91 and Abbe numbers between 37 and 41 have excellent application prospects. To increase the degree of freedom in optical system design, optical glasses with a variety of different performance characteristics are required. Optical glasses with the ability to adequately or as much as possible eliminate residual chromatic aberration in the secondary spectrum, especially those with low relative partial dispersion (P g,F ) and negative anomalous dispersion have attracted attention. Chinese patent application CN103288344A discloses optical glass with a refractive index of 1.86 to 1.90 and an Abbe number of 35 to 40, and its relative partial dispersion (P g,F ) and does not have negative anomalous dispersion. Summary of the Invention [Problem to be solved by the invention]

[0003] The technical problem that the present invention seeks to solve is to provide an optical glass that has negative anomalous dispersion. [Means for solving the problem]

[0004] The technical means adopted by the present invention to solve the technical problems are as follows:

[0005] (1) An optical glass having a composition expressed in weight percentages of SiO2: 4% to 11%, B2O3: 8% to 15%, La2O3: more than 45% and not more than 55%, Gd2O3: 2% to 9.5%, Y2O3: 4% to 10%, ZrO2: 3% to 10%, Nb2O5: 5% to 12%, TiO2: 0.1% to 5%, and Al2O3: more than 0% and not more than 4%, and wherein (La2O3 + Y2O3) / (Nb2O5 + ZrO2) is 2.5 to 6.5.

[0006] (2) The optical glass described in (1) above further contains, when expressed as a composition by weight percentage, 0-4% ZnO, and / or 0-5% RO, and / or 0-5% RnO, and / or 0-5% WO, and / or 0-5% TaO, and / or 0-5% YbO, and / or 0-5% GeO, and / or 0-4% fining agent, where RO is one or more of MgO, CaO, SrO, and BaO; RnO is one or more of LiO, NaO, and KO; and the fining agent is one or more of SbO, SnO, and CeO.

[0007] (3) Optical glass, the composition of which contains SiO2, B2O3, La2O3, Gd2O3, Y2O3, ZrO2, Nb2O5, TiO2, and Al2O3, and the composition expressed as a weight percentage is (La2O3+Y2O3) / (Nb2O5+ZrO2) of 2.5 to 6.5, and the optical glass has a refractive index n d is 1.86 to 1.91, and the Abbe number ν d is 37-41, and the relative partial variance P g,F is less than 0.7000, and the relative partial dispersion deviation value ΔP g,F is less than or equal to -0.0020.

[0008] (4) The optical glass described in (3) above has a composition, expressed in weight percentage, of SiO2: 4% to 11%, and / or B2O3: 8% to 15%, and / or La2O3: more than 45% and not more than 55%, and / or Gd2O3: 2% to 9.5%, and / or Y2O3: 4% to 10%, and / or ZrO2: 3% to 10%, and / or Nb2O5: 5% to 12%, and / or TiO2: 0.1% to 5%, and / or Al2O3: more than 0% and not more than 4%, and / or ZnO: 0 to 4%. and / or RO: 0-5%, and / or Rn2O: 0-5%, and / or WO3: 0-5%, and / or Ta2O5: 0-5%, and / or Yb2O3: 0-5%, and / or GeO2: 0-4%, and / or fining 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 fining agent is one or more of Sb2O3, SnO2, and CeO2.

[0009] (5) The optical glass according to any one of the above items (1) to (4) has a composition expressed in weight percentage as follows: 1) When Gd2O3 / Y2O3 is 0.25 to 1.1, preferably Gd2O3 / Y2O3 is 0.3 to 1.0, more preferably Gd2O3 / Y2O3 is 0.4 to 0.9, and even more preferably Gd2O3 / Y2O3 is 0.5 to 0.9, 2) When Gd2O3 / SiO2 is 0.2 to 1.0, preferably Gd2O3 / SiO2 is 0.3 to 0.95, more preferably Gd2O3 / SiO2 is 0.4 to 0.9, and even more preferably Gd2O3 / SiO2 is 0.5 to 0.9, 3) When Al2O3 / TiO2 is 0.05 to 3.0, preferably Al2O3 / TiO2 is 0.1 to 2.0, more preferably Al2O3 / TiO2 is 0.1 to 1.5, and even more preferably Al2O3 / TiO2 is 0.2 to 1.0, 4) (La2O3 + Y2O3) / (Nb2O5 + ZrO2) is 2.8 to 6.0, preferably (La2O3 + Y2O3) / (Nb2O5 + ZrO2) is 3.0 to 5.5, and more preferably (La2O3 + Y2O3) / (Nb2O5 + ZrO2) is 3.5 to 5.0; 5) When Al2O3 / Gd2O3 is 0.02 to 0.8, preferably Al2O3 / Gd2O3 is 0.05 to 0.6, more preferably Al2O3 / Gd2O3 is 0.1 to 0.5, and even more preferably Al2O3 / Gd2O3 is 0.1 to 0.4, 6) (La2O3+Nb2O5) / Gd2O3 is 6.0 to 23.0, preferably (La2O3+Nb2O5) / Gd2O3 is 8.0 to 20.0, more preferably (La2O3+Nb2O5) / Gd2O3 is 9.0 to 15.0, and even more preferably (La2O3+Nb2O5) / Gd2O3 is 10.0 to 13.0, 7) When Nb2O5 / Y2O3 is 0.6 to 2.0, preferably 0.7 to 1.7, more preferably 0.8 to 1.5, and even more preferably 0.9 to 1.2, 8) One or more of the following eight conditions is satisfied: Al2O3 / SiO2 is 0.01 to 0.8, preferably Al2O3 / SiO2 is 0.05 to 0.6, more preferably Al2O3 / SiO2 is 0.08 to 0.5, and even more preferably Al2O3 / SiO2 is 0.1 to 0.3.

[0010] (6) The optical glass according to any one of the above items (1) to (4) has a composition expressed in weight percentage as follows: 1) When Y2O3 / (Gd2O3+Ta2O5+ZnO+WO3+GeO2) is 0.9 to 4.0, preferably, Y2O3 / (Gd2O3+Ta2O5+ZnO+WO3+GeO2) is 1.0 to 3.5, more preferably, Y2O3 / (Gd2O3+Ta2O5+ZnO+WO3+GeO2) is 1.0 to 3.0, and even more preferably, Y2O3 / (Gd2O3+Ta2O5+ZnO+WO3+GeO2) is 1.2 to 2.0, 2) (TiO2+ZnO+Ta2O5+WO3) / Nb2O5 is 0.01 to 1.0, preferably (TiO2+ZnO+Ta2O5+WO3) / Nb2O5 is 0.05 to 0.8, more preferably (TiO2+ZnO+Ta2O5+WO3) / Nb2O5 is 0.1 to 0.5, and even more preferably (TiO2+ZnO+Ta2O5+WO3) / Nb2O5 is 0.1 to 0.3; 3) (Ta2O5+ZnO+RO) / TiO2 is 2.5 or less, preferably (Ta2O5+ZnO+RO) / TiO2 is 1.5 or less, more preferably (Ta2O5+ZnO+RO) / TiO2 is 1.0 or less, and even more preferably (Ta2O5+ZnO+RO) / TiO2 is 0.5 or less, and the RO is one or more of MgO, CaO, SrO, and BaO.

[0011] (7) The optical glass according to any one of (1) to (4) above has a composition, expressed in weight percentage, of SiO2: 5% to 10%, preferably SiO2: 5.5% to 9%, and / or B2O3: 10% to 14%, preferably B2O3: 11% to 13.5%, and / or La2O3: 46% to 53%, preferably La2O3: 48% to 52%, and / or Gd2O3: 3% to 8%, preferably Gd2 O3: 4% to 7%, and / or Y2O3: 5% to 9.5%, preferably Y2O3: 5.5% to 8.5%, and / or ZrO2: 4% to 9%, preferably ZrO2: 5% to 8%, and / or Nb2O5: 5.5% to 11%, preferably Nb2O5: 6% to 10%, and / or TiO2: 0.5% to 4%, preferably TiO2: 1% to 3%, and / or Al2O3: 0.1% to 3%, preferably Al2 O3: 0.5% to 2%, and / or ZnO: 0 to 2%, preferably ZnO: 0 to 1%, and / or RO: 0 to 3%, preferably RO: 0 to 1%, and / or Rn2O: 0 to 3%, preferably Rn2O: 0 to 1%, and / or WO3: 0 to 3%, preferably WO3: 0 to 1%, and / or Ta2O5: 0 to 3%, preferably Ta2O5: 0 to 1%, and / or Yb2O3: 0 to 3%, preferably The composition contains 0 to 1% Yb2O3 and / or 0 to 2% GeO2, preferably 0 to 1% GeO2, and / or 0 to 0.5% fining agent, preferably 0 to 0.1% fining agent, and 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 fining agent is one or more of Sb2O3, SnO2, and CeO2.

[0012] (8) The optical glass according to any one of (1) to (4) above has a composition that does not contain ZnO, and / or does not contain MgO, and / or does not contain CaO, and / or does not contain SrO, and / or does not contain BaO, and / or does not contain Li2O, and / or does not contain Na2O, and / or does not contain K2O, and / or does not contain WO3, and / or does not contain Ta2O5, and / or does not contain Yb2O3, and / or does not contain GeO2, and / or does not contain Sb2O3, and / or does not contain SnO2, and / or does not contain CeO2.

[0013] (9) The optical glass according to any one of (1) to (4) above has a refractive index n d is 1.86 to 1.91, preferably 1.87 to 1.90, more preferably 1.88 to 1.89, and the Abbe number ν d is 37 to 41, preferably 38 to 40.5, and more preferably 39 to 40.

[0014] (10) The optical glass according to any one of (1) to (4) above has a thermal expansion coefficient α -30 / 70℃ is 85 x 10 -7 / K or less, preferably 80×10 -7 / K or less, and more preferably 75×10 -7 / K or less, and / or water resistance stability D W is two or more classes, preferably one class, and / or acid resistance stability D A is 2 classes or more, preferably 1 class, and / or Knoop hardness H K is 680 x 10 7 Pa or more, preferably 690 x 10 7 Pa or more, more preferably 700×10 7 Pa or greater, and / or relative partial dispersion P g,F is 0.7000 or less, preferably 0.6500 or less, more preferably 0.6000 or less, and / or the relative partial dispersion deviation value ΔP g,Fis -0.0020 or less, preferably -0.0040 or less, more preferably -0.0050 or less, even more preferably -0.0058 or less, and / or the cellularity is level A or more, preferably level A0 or more, more preferably level A 00 and / or the degree of striae is level C or higher, preferably level B or higher, and / or the density ρ is 5.10 g / cm 3 Preferably, it is 5.00 g / cm or less. 3 More preferably, 4.95 g / cm 3 and / or the devitrification resistance is level C or higher, preferably level B or higher, and more preferably level A.

[0015] (11) A glass preform made from the optical glass according to any one of (1) to (10) above.

[0016] (12) An optical element, which is manufactured from the optical glass according to any one of (1) to (10) above, or from the glass preform according to (11) above.

[0017] (13) An optical instrument, which contains the optical glass according to any one of (1) to (10) above and / or the optical element according to (12) above. [Effects of the Invention]

[0018] The beneficial effect of the present invention is that the optical glass of the present invention has a desired refractive index and Abbe number through rational composition design, as well as negative anomalous dispersion, and is therefore applicable to high-performance optical systems. DETAILED DESCRIPTION OF THE INVENTION

[0019] Hereinafter, embodiments of the optical glass of the present invention will be described in detail. However, the present invention is not limited to the following embodiments, and can be practiced with appropriate modifications within the scope of the object of the present invention. Furthermore, although redundant explanations may be omitted as appropriate, this does not limit the spirit of the invention, and hereinafter the optical glass of the present invention may be simply referred to as glass.

[0020] [Optical glass] The range of each composition (component) of the optical glass of the present invention will be explained below. In the present invention, unless otherwise specified, the content of each composition and the total content are all expressed in weight percentage (wt%), that is, the content of each composition and the total content are expressed as weight percentages relative to the total amount of glass material in terms of oxide composition. Here, the term "composition in terms of oxide" refers to the case where oxides, composite salts, hydroxides, etc. used as raw materials for the composition components of the optical glass of the present invention decompose to oxides during melting, and the total amount of the oxide material is taken as 100%.

[0021] The numerical ranges described herein include upper and lower limits unless otherwise specified in a specific instance, and the terms "greater than or equal to" and "less than or equal to" include the endpoints and all integers and fractions contained within the range, but are not limited to the specific value recited when the range is defined. As used herein, "and / or" is inclusive, e.g., "A and / or B" means A only, or B only, or both A and B.

[0022] <Essential and optional ingredients> SiO2 can increase the viscosity of molten glass, reduce glass coloration, improve the thermal stability of glass, and improve devitrification resistance. However, if the SiO2 content is too high, the glass becomes more difficult to melt, the transition temperature rises, and the refractive index does not meet the design requirements. Therefore, in the present invention, the SiO2 content is 4% to 11%, preferably 5% to 10%, and more preferably 5.5% to 9%. In some embodiments, the SiO2 content may be 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%, 10.5%, or 11%.

[0023] B2O3 is a glass network-forming component that improves the meltability and devitrification resistance of glass and is also an effective component for imparting low dispersion to glass. However, if the B2O3 content is less than 8%, the stability of the glass decreases. If the B2O3 content is too high, the chemical stability of the glass decreases, making it difficult for the refractive index of the glass to meet the design requirements. Therefore, in the present invention, the B2O3 content is 8% to 15%, preferably 10% to 14%, and more preferably 11% to 13.5%. In some embodiments, the glass may contain 8%, 8.5%, 9%, 9.5%, 10%, 10.5%, 11%, 11.5%, 12%, 12.5%, 13%, 13.5%, 14%, 14.5%, or 15% B2O3.

[0024] La2O3 is a high-refractive-index, low-dispersion component that can improve the refractive index of glass, adjust dispersion, and reduce the high-temperature viscosity of glass. However, if its content is too high, the devitrification resistance of the glass decreases, and the temperature coefficient of refractive index and Abbe number do not meet the design requirements. Therefore, in the present invention, the La2O3 content is greater than 45% but not more than 55%, preferably 46% to 53%, and more preferably 48% to 52%. In some embodiments, the glass may contain more than 45%, 45.1%, 45.5%, 46%, 46.5%, 47%, 47.5%, 48%, 48.5%, 49%, 49.5%, 50%, 50.5%, 51%, 51.5%, 52%, 52.5%, 53%, 53.5%, 54%, 54.5%, or 55% La2O3.

[0025] Gd2O3 is a high-refractive-index, low-dispersion component that reduces the relative partial dispersion of glass and improves chemical stability. If its content is too high, the glass's devitrification resistance deteriorates and its transition temperature increases. Therefore, in the present invention, the Gd2O3 content is 2% to 9.5%, preferably 3% to 8%, and more preferably 4% to 7%. In some embodiments, the glass may contain 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, or 9.5% Gd2O3.

[0026] In some embodiments, by controlling the ratio of the Gd2O3 content to the SiO2 content, Gd2O3 / SiO2, within the range of 0.2 to 1.0, the optical glass has excellent chemical stability, the hardness and porosity of the glass are improved, and an increase in the thermal expansion coefficient can be prevented. Therefore, Gd2O3 / SiO2 is preferably 0.2 to 1.0, more preferably 0.3 to 0.95, even more preferably 0.4 to 0.9, and even more preferably 0.5 to 0.9. In some embodiments, the value of Gd2O3 / SiO2 can be 0.2, 0.23, 0.25, 0.27, 0.3, 0.33, 0.35, 0.37, 0.4, 0.43, 0.45, 0.47, 0.5, 0.53, 0.55, 0.57, 0.6, 0.63, 0.65, 0.67, 0.7, 0.73, 0.75, 0.77, 0.8, 0.83, 0.85, 0.87, 0.9, 0.93, 0.95, 0.97, or 1.0.

[0027] In the present invention, by including 4% or more of Y2O3 and further using Y2O3 in combination with Gd2O3, it is possible to improve the meltability and devitrification resistance of the glass while maintaining a high refractive index and low dispersion. If the Y2O3 content is too high, the stability and devitrification resistance of the glass decrease and the transition temperature increases. Therefore, the Y2O3 content is 4% to 10%, preferably 5% to 9.5%, and more preferably 5.5% to 8.5%. In some embodiments, the glass may contain 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, or 10% Y2O3.

[0028] In some embodiments, the ratio of the Gd2O3 content to the Y2O3 content, Gd2O3 / Y2O3, can be controlled within a range of 0.25 to 1.1 to reduce the thermal expansion coefficient of the glass and improve its chemical stability. Therefore, Gd2O3 / Y2O3 is preferably 0.25 to 1.1, and more preferably 0.3 to 1.0. Furthermore, by controlling Gd2O3 / Y2O3 within a range of 0.4 to 0.9, the devitrification resistance of the glass can be further improved. Therefore, Gd2O3 / Y2O3 is more preferably 0.4 to 0.9, and even more preferably 0.5 to 0.9. In some embodiments, the value of Gd2O3 / Y2O3 can be 0.25, 0.27, 0.3, 0.33, 0.35, 0.37, 0.4, 0.43, 0.45, 0.47, 0.5, 0.53, 0.55, 0.57, 0.6, 0.63, 0.65, 0.67, 0.7, 0.73, 0.75, 0.77, 0.8, 0.83, 0.85, 0.87, 0.9, 0.93, 0.95, 0.97, 1.0, 1.03, 1.05, 1.07, or 1.1.

[0029] Yb2O3 is a high-refractive-index, low-dispersion component, and if its content exceeds 5%, the devitrification resistance of the glass decreases. Therefore, the Yb2O3 content is 0 to 5%, preferably 0 to 3%, more preferably 0 to 1%, and even more preferably no Yb2O3 is contained. In some embodiments, Yb2O3 may be contained in an amount of 0%, more than 0%, 0.01%, 0.05%, 0.1%, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5%.

[0030] ZrO2 improves the refractive index and devitrification resistance of the glass, and reduces the ΔP of the glass. g,F However, if the ZrO2 content is too high, it becomes difficult to melt the glass, inclusions are likely to enter the glass, and light transmittance is likely to decrease, while devitrification resistance of the glass is also reduced. Therefore, in the present invention, the ZrO2 content is 3% to 10%, preferably 4% to 9%, and more preferably 5% to 8%. In some embodiments, the ZrO2 content may be 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, or 10%.

[0031] Nb2O5 has the effect of increasing the refractive index, improving the chemical stability and devitrification resistance, and can reduce the thermal expansion coefficient of the glass. g,F value and ΔP g,F The glass does not significantly improve the glass resistance and light transmittance, and if the content is less than 5%, the above effect is not significant. If the Nb2O5 content exceeds 12%, the weather resistance and light transmittance of the glass decrease, and the glass transition temperature increases. Therefore, the Nb2O5 content is 5% to 12%, preferably 5.5% to 11%, and more preferably 6% to 10%. In some embodiments, the glass may contain 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%, 10.5%, 11%, 11.5%, or 12% Nb2O5.

[0032] In some embodiments, by controlling the ratio (La2O3+Y2O3) / (Nb2O5+ZrO2) of the total content of La2O3 and Y2O3 (La2O3+Y2O3) to the total content of Nb2O5 and ZrO2 (Nb2O5+ZrO2) within the range of 2.5 to 6.5, the optical glass can easily obtain a desired refractive index and Abbe number, and the P of the glass can be improved. g,F value and ΔP g,F The value can be reduced. Therefore, preferably, (La2O3 + Y2O3) / (Nb2O5 + ZrO2) is 2.5 to 6.5, and more preferably, (La2O3 + Y2O3) / (Nb2O5 + ZrO2) is 2.8 to 6.0. Furthermore, by controlling (La2O3 + Y2O3) / (Nb2O5 + ZrO2) to a range of 3.0 to 5.5, the hardness of the glass can be further improved. Therefore, more preferably, (La2O3 + Y2O3) / (Nb2O5 + ZrO2) is 3.0 to 5.5, and even more preferably, (La2O3 + Y2O3) / (Nb2O5 + ZrO2) is 3.5 to 5.0. In some embodiments, the value of (La2O3 + Y2O3) / (Nb2O5 + ZrO2) can be 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9, 5.0, 5.1, 5.2, 5.3, 5.4, 5.5, 5.6, 5.7, 5.8, 5.9, 6.0, 6.1, 6.2, 6.3, 6.4, or 6.5.

[0033] In some embodiments, the ratio (La2O3+Nb2O5) / Gd2O3 of the total content of La2O3 and Nb2O5 (La2O3+Nb2O5) to the content of Gd2O3 is controlled within a range of 6.0 to 23.0, thereby controlling the density and P of the glass. g,F value and ΔP g,FThis reduces the value, thereby improving the chemical stability and bubble content of the glass. Therefore, preferably, (La2O3+Nb2O5) / Gd2O3 is 6.0 to 23.0, more preferably, (La2O3+Nb2O5) / Gd2O3 is 8.0 to 20.0, even more preferably, (La2O3+Nb2O5) / Gd2O3 is 9.0 to 15.0, and even more preferably, (La2O3+Nb2O5) / Gd2O3 is 10.0 to 13.0. In some embodiments, the value of (La2O3 + Nb2O5) / Gd2O3 can be 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5, 10.0, 10.5, 11.0, 11.5, 12.0, 12.5, 13.0, 13.5, 14.0, 14.5, 15.0, 15.5, 16.0, 16.5, 17.0, 17.5, 18.0, 18.5, 19.0, 19.5, 20.0, 20.5, 21.0, 21.5, 22.0, 22.5, or 23.0.

[0034] In some embodiments, by controlling the ratio of the Nb2O5 content to the Y2O3 content, Nb2O5 / Y2O3, within the range of 0.6 to 2.0, the optical glass will have the desired refractive index and Abbe number, the glass's bubble content will be improved, and a decrease in weather resistance and devitrification resistance will be prevented. Therefore, Nb2O5 / Y2O3 is preferably 0.6 to 2.0, more preferably 0.7 to 1.7, even more preferably 0.8 to 1.5, and even more preferably 0.9 to 1.2. In some embodiments, the values ​​of Nb2O5 / Y2O3 are 0.6, 0.63, 0.65, 0.67, 0.7, 0.73, 0.75, 0.77, 0.8, 0.83, 0.85, 0.87, 0.9, 0.93, 0.95, 0.97, 1.0, 1.03, 1.05, 1.07, 1.1, 1.13, 1.15, 1.17, 1.2, 1.23, 1.24, 1.25, 1.26, 1.27, 1.28, 1.29, 1.30, 1.31, 1.32, 1.33, 1.34, 1.35, 1.36, 1.37, 1.38, 1.39, 1.40, 1.41, 1.42, 1.43, 1.44, 1.45, 1.46, 1.47, 1.48, 1.49, 1.50, 1.51, 1.52, 1.53, 1.54, 1.55, 1.56, 1.57, 1.58, 1.59, 1.60, 1.61, 1.62, 1.63, 1.64, 1.65, 1.66, 1.67, 1.68, 1.69, 1.70, 1.71, 1.72, 1.73, 1.74, 1.75, 1.76, 1.77, 1.78, 1.79, 1.80, 1 1.5, 1.27, 1.3, 1.33, 1.35, 1.37, 1.4, 1.43, 1.45, 1.47, 1.5, 1.53, 1.55, 1.57, 1.6, 1.63, 1.65, 1.67, 1.7, 1.73, 1.75, 1.77, 1.8, 1.83, 1.85, 1.87, 1.9, 1.93, 1.95, 1.97, or 2.0.

[0035] Al2O3 reduces the thermal expansion coefficient of glass and can improve the devitrification resistance and thermal stability of glass. However, if the Al2O3 content is too high, the glass transition temperature increases and the melting property of the glass deteriorates. Therefore, in the present invention, the Al2O3 content is greater than 0 and 4% or less, preferably 0.1% to 3%, and more preferably 0.5% to 2%. In some embodiments, the Al2O3 content may be greater than 0%, 0.01%, 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, or 4%.

[0036] In some embodiments, the ratio of the Al2O3 content to the SiO2 content, Al2O3 / SiO2, can be controlled within the range of 0.01 to 0.8 to improve the devitrification resistance and the degree of striae of the glass and optimize the abrasion resistance of the glass. Therefore, Al2O3 / SiO2 is preferably 0.01 to 0.8, more preferably 0.05 to 0.6, even more preferably 0.08 to 0.5, and even more preferably 0.1 to 0.3. In some embodiments, the value of Al2O3 / SiO2 can be 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.13, 0.15, 0.17, 0.2, 0.23, 0.25, 0.27, 0.3, 0.33, 0.35, 0.37, 0.4, 0.43, 0.45, 0.47, 0.5, 0.53, 0.55, 0.57, 0.6, 0.63, 0.65, 0.67, 0.7, 0.73, 0.75, 0.77, or 0.8.

[0037] In some embodiments, the ratio of the Al2O3 content to the Gd2O3 content, Al2O3 / Gd2O3, can be controlled within the range of 0.02 to 0.8 to improve the degree of striae and hardness of the glass and optimize the devitrification resistance of the glass. Therefore, Al2O3 / Gd2O3 is preferably 0.02 to 0.8, more preferably 0.05 to 0.6, even more preferably 0.1 to 0.5, and even more preferably 0.1 to 0.4. In some embodiments, the value of Al2O3 / Gd2O3 can be 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.13, 0.15, 0.17, 0.2, 0.23, 0.25, 0.27, 0.3, 0.33, 0.35, 0.37, 0.4, 0.43, 0.45, 0.47, 0.5, 0.53, 0.55, 0.57, 0.6, 0.63, 0.65, 0.67, 0.7, 0.73, 0.75, 0.77, or 0.8.

[0038] TiO2 has the effect of improving the refractive index and dispersion of glass. In the present invention, when an appropriate amount of TiO2 is contained, the stability of the glass can be improved and the devitrification resistance of the glass can be improved. However, if the content of TiO2 exceeds 5%, the P g,F value and ΔP g,F The TiO2 content increases, and at the same time, the glass becomes more susceptible to crystallization during press molding. Therefore, in the present invention, the TiO2 content is 0.1% to 5%, preferably 0.5% to 4%, and more preferably 1% to 3%. In some embodiments, the TiO2 content may be 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5%.

[0039] In some embodiments, the devitrification resistance and hardness of the glass can be improved and the degree of striae in the glass can be optimized by controlling the ratio of the Al2O3 content to the TiO2 content, Al2O3 / TiO2, within the range of 0.05 to 3.0. Therefore, Al2O3 / TiO2 is preferably 0.05 to 3.0, more preferably 0.1 to 2.0, even more preferably 0.1 to 1.5, and even more preferably 0.2 to 1.0. In some embodiments, the values ​​of Al2O3 / TiO2 are 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, 1.0, 1.1 It may be 0.05, 1.1, 1.15, 1.2, 1.25, 1.3, 1.35, 1.4, 1.45, 1.5, 1.55, 1.6, 1.65, 1.7, 1.75, 1.8, 1.85, 1.9, 1.95, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, or 3.0.

[0040] ZnO is an optional component of the present invention, and can improve the chemical stability of glass, enhance the weather resistance of glass, and lower the glass transition temperature. However, if the ZnO content is too high, it increases corrosion of platinum equipment during melting, shortens the service life of the melting furnace, and is detrimental to the devitrification resistance of the glass. Therefore, in the present invention, the ZnO content is 0 to 4%, preferably 0 to 2%, more preferably 0 to 1%, and even more preferably, ZnO is not contained. In some embodiments, ZnO may comprise 0%, greater than 0%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, or 4%.

[0041] WO3 can improve the refractive index and mechanical strength of glass, but a WO3 content greater than 5% reduces the thermal stability and devitrification resistance of the glass. Therefore, in the present invention, the WO3 content is 0 to 5%, preferably 0 to 3%, and more preferably 0 to 1%. In some embodiments, it is even more preferable to have no WO3. In some embodiments, WO3 may be present in an amount of 0%, greater than 0%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5%.

[0042] Ta2O5 has the effect of increasing the refractive index of glass and improving devitrification resistance, but if its content is too high, the thermal stability of the glass decreases and the density increases, which is disadvantageous in controlling the cost of glass raw materials. Therefore, in the present invention, the Ta2O5 content is 0 to 5%, preferably 0 to 3%, and more preferably 0 to 1%. In some embodiments, it is even more preferable that Ta2O5 is not contained. In some embodiments, Ta2O5 may include 0%, greater than 0%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5%.

[0043] In some embodiments, the ratio of the total content of TiO2, ZnO, Ta2O5, and WO3 to the content of Nb2O5 (TiO2 + ZnO + Ta2O5 + WO3) / Nb2O5 is controlled within the range of 0.01 to 1.0, thereby reducing the thermal expansion coefficient of the glass, improving the degree of bubbles in the glass, and reducing P g,F value and ΔP g,FTherefore, preferably, (TiO2+ZnO+Ta2O5+WO3) / Nb2O5 is 0.01 to 1.0, more preferably, (TiO2+ZnO+Ta2O5+WO3) / Nb2O5 is 0.05 to 0.8, even more preferably, (TiO2+ZnO+Ta2O5+WO3) / Nb2O5 is 0.1 to 0.5, and even more preferably, (TiO2+ZnO+Ta2O5+WO3) / Nb2O5 is 0.1 to 0.3. In some embodiments, the value of (TiO2 + ZnO + Ta2O5 + WO3) / Nb2O5 is 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.13, 0.15, 0.17, 0.2, 0.23, 0.25, 0.27, 0.3, 0.33, 0.40, 0.45, 0.46, 0.47, 0.50, 0.51, 0.52, 0.53, 0.54, 0.55, 0.56, 0.57, 0.58, 0.60, 0.61, 0.62, 0.63, 0.64, 0.65, 0.66, 0.67, 0.68, 0.69, 0.70, 0.71, 0.72, 0.73, 0.74, 0.75, 0.76, 0.77, 0.78, 0.79, 0.80, 0.81, 0.82, 0.83, 0.84, 0.85, 0.86, 0.87, 0.88, 0.89, 0.90, 0.91, 0.92, 0.93, 0.94, 0.95, 0.96, 0.97, 0.98, 0.99, 100, 100, 100, 100, 100, 100, 100, 100, 100, 100, It may be 0.35, 0.37, 0.4, 0.43, 0.45, 0.47, 0.5, 0.53, 0.55, 0.57, 0.6, 0.63, 0.65, 0.67, 0.7, 0.73, 0.75, 0.77, 0.8, 0.83, 0.85, 0.87, 0.9, 0.93, 0.95, 0.97, or 1.0.

[0044] GeO2 has the effect of improving the refractive index and devitrification resistance of glass, but if its content is too high, the chemical stability of the glass will decrease, and on the other hand, GeO2 is very expensive compared to other components, so its amount must be kept as small as possible from the perspective of glass raw material costs. Therefore, in the present invention, the GeO2 content is limited to 0 to 4%, preferably 0 to 2%, more preferably 0 to 1%, and even more preferably, GeO2 is not contained. Some embodiments may include 0%, greater than 0%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, or 4% GeO2.

[0045] In some embodiments, by controlling the ratio of the Y2O3 content to the total content of Gd2O3, Ta2O5, ZnO, WO3, and GeO2, Y2O3 / (Gd2O3+Ta2O5+ZnO+WO3+GeO2), within the range of 0.9 to 4.0, the degree of bubbles and striae in the glass can be improved and the density of the glass can be reduced. Therefore, preferably, Y2O3 / (Gd2O3+Ta2O5+ZnO+WO3+GeO2) is 0.9 to 4.0, more preferably, Y2O3 / (Gd2O3+Ta2O5+ZnO+WO3+GeO2) is 1.0 to 3.5, even more preferably, Y2O3 / (Gd2O3+Ta2O5+ZnO+WO3+GeO2) is 1.0 to 3.0, and even more preferably, Y2O3 / (Gd2O3+Ta2O5+ZnO+WO3+GeO2) is 1.2 to 2.0. In some embodiments, the value of Y2O3 / (Gd2O3+Ta2O5+ZnO+WO3+GeO2) is 0.9, 0.95, 1.0, 1.05, 1.1, 1.15, 1.2, 1.25, 1.3, 1.35, 1.4, 1.45, 1.5, 1.55, 1.6, 1.65, 1.7, 1.75, 1.8, 1.85, 1.9, 1.05, 1.15, 1.25, 1.35, 1.45, 1.5, 1.55, 1.6, 1.65, 1.7, 1.75, 1.8, 1.85, 1.9, 1.05, 1.05, 1.1 ... It may be 0.95, 2.0, 2.05, 2.1, 2.15, 2.2, 2.25, 2.3, 2.35, 2.4, 2.45, 2.5, 2.55, 2.6, 2.65, 2.7, 2.75, 2.8, 2.85, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, or 4.0.

[0046] RO (RO is one or more of MgO, CaO, SrO, and BaO) can improve the meltability of glass and adjust the optical constants of glass, but if the RO content exceeds 5%, the devitrification resistance of the glass decreases. Therefore, in the present invention, the RO content is 0 to 5%, preferably 0 to 3%, and more preferably 0 to 1%. In some embodiments, it is more preferable that the glass does not contain MgO, and / or does not contain CaO, and / or does not contain SrO, and / or does not contain BaO. Some embodiments may include 0%, greater than 0%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5% RO. Some embodiments may include 0%, greater than 0%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5% MgO. Some embodiments may include 0%, greater than 0%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5% CaO. Some embodiments may include 0%, greater than 0%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5% SrO.Some embodiments may include 0%, greater than 0%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5% BaO.

[0047] In some embodiments, the ratio of the total content of Ta2O5, ZnO, and RO (Ta2O5+ZnO+RO) to the content of TiO2 (Ta2O5+ZnO+RO) / TiO2 can be controlled to 2.5 or less, thereby reducing the thermal expansion coefficient and density of the glass and optimizing the degree of striae in the glass. Therefore, preferably, (Ta2O5+ZnO+RO) / TiO2 is 2.5 or less, more preferably, (Ta2O5+ZnO+RO) / TiO2 is 1.5 or less, even more preferably, (Ta2O5+ZnO+RO) / TiO2 is 1.0 or less, and even more preferably, (Ta2O5+ZnO+RO) / TiO2 is 0.5 or less. In some embodiments, the value of (Ta2O5+ZnO+RO) / TiO2 is 0, greater than 0, 0.01, 0.03, 0.05, 0.07, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, 1. It may be 0, 1.05, 1.1, 1.15, 1.2, 1.25, 1.3, 1.35, 1.4, 1.45, 1.5, 1.55, 1.6, 1.65, 1.7, 1.75, 1.8, 1.85, 1.9, 1.95, 2.0, 2.05, 2.1, 2.15, 2.2, 2.25, 2.3, 2.35, 2.4, 2.45, or 2.5.

[0048] RnO (RnO is one or more of LiO, NaO, and KO) can lower the glass transition temperature, adjust the optical constants and high-temperature viscosity of the glass, and improve the meltability of the glass. However, if the RnO content is too high, the devitrification resistance and chemical stability of the glass decrease. Therefore, in the present invention, the RnO content is 0 to 5%, preferably 0 to 3%, and more preferably 0 to 1%. In some embodiments, it is more preferable that the glass does not contain LiO, NaO, and / or KO. Some embodiments may include 0%, greater than 0%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5% RnO. Some embodiments may include 0%, greater than 0%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5% LiO. Some embodiments may include 0%, greater than 0%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5% NaO. Some embodiments may include 0%, greater than 0%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5% KO.

[0049] In the present invention, the inclusion of 0-1% of one or more of Sb2O3, SnO2, and CeO2 as a fining agent can improve the fining effect of the glass and increase the cellularity of the glass. Preferably, the fining agent content is 0-0.5%, and more preferably, 0-0.1%. The optical glass of the present invention has a rational design of the types and contents of components, resulting in an excellent cellularity. Therefore, in some embodiments, it is preferable that the glass does not contain a fining agent. If the Sb2O3 content exceeds 1%, the fining ability of the glass tends to decrease, and its strong oxidizing effect accelerates corrosion of the platinum or platinum alloy vessel used to melt the glass and deterioration of the molding die. Therefore, in the present invention, the Sb2O3 content is preferably 0-1%, more preferably 0-0.5%, even more preferably 0-0.1%, and even more preferably, no Sb2O3 is contained. SnO2 may be used as a fining agent, but if its content exceeds 1%, the glass tends to become more colored, or when the glass is heated, softened, and reshaped by press molding or the like, Sn becomes the starting point for crystal nucleation, tending to cause devitrification. Therefore, the SnO2 content of the present invention is preferably 0 to 1%, more preferably 0 to 0.5%, even more preferably 0 to 0.1%, and even more preferably, no SnO2 is contained. The function and content of CeO2 are the same as those of SnO2, and its content is preferably 0 to 1%, more preferably 0 to 0.5%, even more preferably 0 to 0.1%, and even more preferably, no CeO2 is contained. In some embodiments, the fining agent may be present at 0%, greater than 0%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, or 1%. In some embodiments, the fining agent may be present at 0%, greater than 0%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, or 1%.In some embodiments, the composition may contain 0%, greater than 0%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, or 1% SnO2. In some embodiments, the composition may contain 0%, greater than 0%, 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, or 1% CeO2.

[0050] <Prohibited ingredients> In the glass of the present invention, even when oxides of transition metals such as V, Cr, Mn, Fe, Co, Ni, Cu, Ag, and Mo are contained alone or in combination, even in small amounts, they color the glass and cause absorption at specific wavelengths in the visible light region, thereby weakening the property of the present invention of improving visible light transmittance. Therefore, it is preferable that these oxides are substantially absent, particularly in optical glasses that require transmittance at wavelengths in the visible light region.

[0051] In recent years, there has been a trend to reduce the use of oxides of Th, Cd, Tl, Os, Be, and Se as harmful chemicals, and environmental protection measures are required not only in the glass manufacturing process but also in the processing process and disposal after commercialization. Therefore, when environmental impact is a priority, it is preferable to substantially not contain these elements except for unavoidable contamination. This ensures that the optical glass is substantially free of environmentally polluting substances. Therefore, the optical glass of the present invention can be manufactured, processed, and disposed of without the need for special environmental measures.

[0052] Due to environmental considerations, the optical glass of the present invention preferably does not contain As2O3 and PbO.

[0053] The terms "not contained" and "0%" used in this specification mean that the relevant compound, molecule, element, etc. is not intentionally added to the optical glass of the present invention as a raw material. However, some impurities or components that are not intentionally added may exist in the raw materials and / or equipment used to produce the optical glass, and may be contained in small or trace amounts in the final optical glass. Such cases are also within the scope of protection of the present invention patent.

[0054] The performance of the optical glass of the present invention will now be described.

[0055] <Refractive index and Abbe number> The refractive index of optical glass (n d ) and Abbe number (v d ) is measured according to the method specified in GB / T7962.1-2010.

[0056] In some embodiments, the refractive index (n d The lower limit of ) is 1.86, preferably 1.87, and more preferably 1.88.

[0057] In some embodiments, the refractive index (n d ) is 1.91, preferably 1.90, and more preferably 1.89.

[0058] In some embodiments, the Abbe number (ν d The lower limit of ) is 37, preferably 38, and more preferably 39.

[0059] In some embodiments, the Abbe number (ν d ) is 41, preferably 40.5, and more preferably 40.

[0060] <Thermal expansion coefficient> The thermal expansion coefficient of optical glass (α -30 / 70℃) is measured at temperatures between -30℃ and 70℃ according to the method specified in "GB / T7962.16-2010".

[0061] In some embodiments, the coefficient of thermal expansion (α -30 / 70℃ ) is 85 x 10 -7 / K or less, preferably 80×10 -7 / K or less, and more preferably 75×10 -7 / K or less.

[0062] <Water resistance stability> Water resistance stability of optical glass (D W ) (powder method) is measured according to the method specified in GB / T17129.

[0063] In some embodiments, the water action stability (D W ) is two or more classes, preferably one class.

[0064] <Acid resistance stability> Acid resistance stability of optical glass (D A ) (powder method) is measured according to the method specified in GB / T17129.

[0065] In some embodiments, the acid attack stability (D A ) is two or more classes, preferably one class.

[0066] <Knoop hardness> Knoop hardness of optical glass (H K ) is measured in accordance with the measurement method specified in "GB / T7962.18-2010." In the present invention, the Knoop hardness may be simply referred to as hardness.

[0067] In some embodiments, the Knoop hardness (H K ) is 680 x 10 7 Pa or more, preferably 690 x 10 7Pa or more, more preferably 700×10 7 Pa or more.

[0068] <Relative partial variance and relative partial variance deviation> Relative partial variance (P g,F ) and relative partial variance deviation (ΔP g,F The origin of this is explained in the following formula:

[0069] The relative partial dispersion for wavelengths x and y is expressed by the following formula (1).

[0070] P x,y =(n x -n y ) / (n F -n C ) (1) According to the Abbe number formula, the following formula (2) holds for many so-called "normal glasses" (hereinafter, H-K6 and F4 are selected as "normal glasses").

[0071] P x,y =m x,y ·v d +b x,y (2) Such a linear relationship is x,y is the ordinate, v d is expressed as the abscissa, where m x,y is the slope and b x,y is the intercept.

[0072] As is well known, correction of secondary spectra, i.e., achromatization for two or more wavelengths, requires the correction of at least one glass that does not conform to formula (2) above (i.e., its P x,y The deviation value is ΔP x,y When expressed as x,y -v d ΔP relative to the "normal line" where the points fit the above equation (2). x,y Thus, the ΔP of each glass x,y The value is calculated using the following formula (3).

[0073] Px,y =m x,y ·v d +b x,y +ΔP x,y (3) Therefore, ΔP x,y indicates quantitatively the deviation characteristics of the special dispersion when compared with "normal glass."

[0074] Therefore, the relative partial variance (P g,F ) and relative partial variance deviation (ΔP g,F The calculation formulas for (4) and (5) are as follows: P g,F =(n g -n F ) / (n F -n C ) (4) ΔP g,F =P g,F -0.6457+0.001703v d (5)

[0075] In some embodiments, the optical glasses of the present invention have a relative partial dispersion (P g,F ) is 0.7000 or less, preferably 0.6500 or less, and more preferably 0.6000 or less.

[0076] In some embodiments, the optical glass of the present invention has a relative partial dispersion deviation (ΔP g,F ) is −0.0020 or less, preferably −0.0040 or less, more preferably −0.0050 or less, and even more preferably −0.0058 or less.

[0077] <Bubble content> The bubble content of optical glass is measured according to the method specified in GB / T7962.8-2010.

[0078] In some embodiments, the cellularity of the optical glass of the present invention is at least Level A, preferably at least Level A0, and more preferably at least Level A. 00 is.

[0079] <Level of striae> The degree of striae in optical glass is determined by a striae inspection device consisting of a point light source and a lens, which is compared with a standard sample from the direction in which the striae are most visible. The details are shown in Table 1 below. [Table 1]

[0080] In some embodiments, the degree of striae in the optical glass of the present invention is level C or higher, preferably level B or higher.

[0081] <density> The density (ρ) of optical glass is measured according to the method specified in GB / T7962.20-2010.

[0082] In some embodiments, the density (ρ) of the optical glass of the present invention is 5.10 g / cm 3 Preferably, it is 5.00 g / cm or less. 3 More preferably, 4.95 g / cm 3 The following is the result.

[0083] <Devitrification resistance performance> The devitrification resistance of the optical glass according to the present invention was measured as follows: A glass sample measuring 10 mm x 20 mm x 20 mm was placed in a semicircular ceramic case with a radius of 15 mm and a depth of 15 mm. g The first heating was carried out in a test furnace at +230°C for 12 minutes, after which it was taken out and cooled to 200°C in a tunnel annealing furnace. g The second heating was carried out in a test furnace stabilized at +230°C, and the heating time was 12 minutes. After that, it was taken out and cooled to 200°C in a tunnel annealing furnace. After that, the set temperature was T gThe glass sample was placed in a stable test furnace at +230°C for a third heating period of 12 minutes. After the third heating period, the glass sample and ceramic case were placed in a tunnel annealing furnace and cooled to 200°C. The glass sample was then removed and allowed to cool naturally to room temperature in an atmospheric environment. After polishing the glass sample, the overall degree of softening and devitrification of the glass were observed with the naked eye, and the interior of the glass was observed under a microscope to confirm the presence of crystallized particles. The devitrification resistance of the glass was then determined from Table 2 below, with Level A being the best and Level E being the worst.

[0084] [Table 2]

[0085] In some embodiments, the devitrification resistance of the optical glass of the present invention is Level C or higher, preferably Level B or higher, and more preferably Level A.

[0086] [Optical glass manufacturing method] The method for producing the optical glass of the present invention is as follows. The glass of the present invention is produced using conventional raw materials and processes, including, but not limited to, oxides, hydroxides, complex salts (e.g., carbonates, nitrates, sulfates, etc.), boric acid, etc., by blending the raw materials in a conventional manner, and then charging the blended furnace material into a melting furnace (e.g., a platinum or platinum alloy crucible) at 1200 to 1500°C for melting. After undergoing fining and homogenization, a homogeneous molten glass free of bubbles and undissolved materials is obtained, and this molten glass is then cast into a mold and annealed to produce the glass. Those skilled in the art will be able to appropriately select the raw materials, process methods, and process parameters according to actual needs.

[0087] [Glass preforms and optical elements] From the produced optical glass, a glass preform can be produced, for example, by direct gob molding, polishing, or press molding such as hot press molding. That is, a glass precision preform can be produced by directly subjecting molten optical glass to precision gob molding, by subjecting the molten optical glass to mechanical processing such as grinding and polishing, or by producing a preform for press molding from the optical glass, re-hot press molding the preform, and then polishing the preform. Note that the means for producing a glass preform are not limited to those described above.

[0088] As described above, the optical glass of the present invention is useful for various optical elements and optical designs, and it is particularly preferable to form a preform from the optical glass of the present invention and use the preform to carry out reheat press molding, precision press molding, or the like to produce optical elements such as lenses and prisms.

[0089] The glass preform and optical element of the present invention are both formed from the optical glass of the present invention. The glass preform of the present invention has the excellent properties of optical glass, and the optical element of the present invention has the excellent properties of optical glass, making it possible to provide optical elements such as various lenses and prisms with high optical value.

[0090] Examples of lenses include various lenses whose lens surfaces are spherical or aspherical, such as concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, and plano-concave lenses.

[0091] [Optical equipment] Optical elements formed from the optical glass of the present invention can be used to manufacture optical devices such as cameras, imaging devices, projection devices, display devices, in-vehicle devices, and monitoring devices.

[0092] Example <Examples of optical glass> In order to further clearly interpret and explain the technical solutions of the present invention, the following non-limiting examples are provided.

[0093] In the present examples, the optical glass manufacturing method described above is used to obtain optical glasses having the compositions shown in Tables 3 to 5. In addition, the properties of each glass are measured using the measurement methods described in the present invention, and the measurement results are shown in Tables 3 to 5.

[0094] [Table 3] TIFF2025174890000004.tif70170

[0095] [Table 4] TIFF2025174890000006.tif68170

[0096] [Table 5] TIFF2025174890000008.tif58170

[0097] <Example of glass preform> From the glasses obtained in Examples 1# to 21# of optical glasses, various lenses such as concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, and plano-concave lenses, as well as preforms such as prisms, are manufactured using, for example, polishing means or press molding means such as reheat press molding and precision press molding.

[0098] <Example of optical element> These preforms obtained in the above glass preform examples are annealed to fine-tune the refractive index while reducing the stress inside the glass so that the optical properties such as the refractive index reach the desired values.

[0099] Next, each preform is 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. An anti-reflection film can also be applied to the surface of the obtained optical element.

[0100] <Example of optical equipment> Optical elements manufactured from the above optical element embodiments can be used in optical designs to form optical components or optical assemblies using one or more optical elements, which can be used in, for example, imaging equipment, sensors, microscopes, medical technology, digital projection, communications, optical communication technology / information transmission, optics / illumination in the automotive field, lithography technology, excimer lasers, wafers, computer chips, and integrated circuits and electronic devices containing such circuits and chips.

Claims

1. The composition expressed in weight percentage is SiO ２ : 4% to 11%, B ２ O ３ :8%~15%, La ２ O ３ : More than 45% and less than 55%, Gd ２ O ３ :2%~9.5%, Y ２ O ３ :4% to 10%, ZrO ２ :3%~10%, Nb ２ O ５ :5%~12%, TiO ２ :0.1%~5%, Al ２ O ３ : Contains more than 0 and 4% or less, (La ２ O ３ +Y ２ O ３ ) / (Nb ２ O ５ + ZrO ２ ) is 2.5 to 6.

5.

2. When the composition is expressed in weight percentage, ZnO: 0 to 4%, and / or RO: 0 to 5%, and / or Rn ２ O: 0 to 5%, and / or WO ３ : 0 to 5%, and / or Ta ２ O ５ : 0 to 5%, and / or Yb ２ O ３ : 0 to 5%, and / or GeO ２ : 0 to 4%, and / or fining agent: 0 to 1%, wherein the RO is one or more of MgO, CaO, SrO, and BaO, and Rn ２ O is Li ２ O, Na ２ O.K. ２ O, and the fining agent is Sb ２ O ３ , SnO ２ , CeO ２ 2. The optical glass according to claim 1, wherein the optical glass is one or more of the following:

3. Optical glass, the composition of which is SiO ２ , B ２ O ３ , La ２ O ３ , Gd ２ O ３ , Y ２ O ３ , ZrO ２ , Nb ２ O ５ , TiO ２ , Al ２ O ３ When the composition is expressed in weight percentage, (La ２ O ３ +Y ２ O ３ ) / (Nb ２ O ５ + ZrO ２ ) is 2.5 to 6.5, and the optical glass has a refractive index n ｄ is 1.86 to 1.91, and the Abbe number ν ｄ is 37-41, and the relative partial dispersion P ｇ，Ｆ is 0.7000 or less, and the relative partial dispersion deviation value ΔP ｇ，Ｆ is -0.0020 or less.

4. The composition expressed in weight percentage is SiO ２ : 4% to 11%, and / or B ２ O ３ : 8% to 15%, and / or La ２ O ３ : More than 45% and 55% or less, and / or Gd ２ O ３ : 2% to 9.5%, and / or Y ２ O ３ : 4% to 10%, and / or ZrO ２ : 3% to 10%, and / or Nb ２ O ５ : 5% to 12%, and / or TiO ２ : 0.1% to 5%, and / or Al ２ O ３ : more than 0 to 4% or less, and / or ZnO: 0 to 4%, and / or RO: 0 to 5%, and / or Rn ２ O: 0 to 5%, and / or WO ３ : 0 to 5%, and / or Ta ２ O ５ : 0 to 5%, and / or Yb ２ O ３ : 0 to 5%, and / or GeO ２ : 0 to 4%, and / or fining agent: 0 to 1%, wherein the RO is one or more of MgO, CaO, SrO, and BaO, and Rn ２ O is Li ２ O, Na ２ O.K. ２ O, and the fining agent is Sb ２ O ３ , SnO ２ , CeO ２ 4. The optical glass according to claim 3, wherein the optical glass is one or more of the following:

5. When the composition is expressed as a weight percentage, 1) Gd ２ O ３ / Y ２ O ３ is between 0.25 and 1.1, 2) Gd ２ O ３ / SiO ２ is between 0.2 and 1.0, 3) Al ２ O ３ / TiO ２ is 0.05 to 3.0, 4) (La ２ O ３ +Y ２ O ３ ) / (Nb ２ O ５ + ZrO ２ ) is 2.8 to 6.0, 5) Al ２ O ３ / Gd ２ O ３ is 0.02 to 0.8, 6) (La ２ O ３ +Nb ２ O ５ ) / Gd ２ O ３ is 6.0 to 23.0, 7) Nb ２ O ５ / Y ２ O ３ is 0.6 to 2.0, 8) Al ２ O ３ / SiO ２ 5. The optical glass according to claim 1, wherein the optical glass satisfies one or more of the following eight conditions: when is 0.01 to 0.

8.

6. When the composition is expressed as a weight percentage, 1) Gd ２ O ３ / Y ２ O ３ is between 0.4 and 0.9, 2) Gd ２ O ３ / SiO ２ is between 0.4 and 0.9, 3) Al ２ O ３ / TiO ２ is between 0.1 and 1.5, 4) (La ２ O ３ +Y ２ O ３ ) / (Nb ２ O ５ + ZrO ２ ) is 3.0 to 5.5, 5) Al ２ O ３ / Gd ２ O ３ is between 0.1 and 0.5, 6) (La ２ O ３ +Nb ２ O ５ ) / Gd ２ O ３ is 9.0 to 15.0, 7) Nb ２ O ５ / Y ２ O ３ is between 0.8 and 1.5, 8) Al ２ O ３ / SiO ２ 5. The optical glass according to claim 1, wherein the optical glass satisfies one or more of the following eight conditions: when is 0.08 to 0.

5.

7. When the composition is expressed as a weight percentage, 1) Gd ２ O ３ / Y ２ O ３ is between 0.5 and 0.9, 2) Gd ２ O ３ / SiO ２ is between 0.5 and 0.9, 3) Al ２ O ３ / TiO ２ is between 0.2 and 1.0, 4) (La ２ O ３ +Y ２ O ３ ) / (Nb ２ O ５ + ZrO ２ ) is 3.5 to 5.0, 5) Al ２ O ３ / Gd ２ O ３ is between 0.1 and 0.4, 6) (La ２ O ３ +Nb ２ O ５ ) / Gd ２ O ３ is 10.0 to 13.0, 7) Nb ２ O ５ / Y ２ O ３ is between 0.9 and 1.2, 8) Al ２ O ３ / SiO ２ 5. The optical glass according to claim 1, wherein the optical glass satisfies one or more of the following eight conditions: when is 0.1 to 0.

3.

8. When the composition is expressed as a weight percentage, 1) Y ２ O ３ / (Gd ２ O ３ +Ta ２ O ５ + ZnO + WO ３ +GeO ２ ) is 0.9 to 4.0, 2) (TiO ２ +ZnO + Ta ２ O ５ +WO ３ ) / Nb ２ O ５ is between 0.01 and 1.0, 3) (Ta ２ O ５ +ZnO+RO) / TiO ２ is less than or equal to 2.5, 5. The optical glass according to claim 1, wherein the RO is one or more of MgO, CaO, SrO, and BaO.

9. When the composition is expressed as a weight percentage, 1) Y ２ O ３ / (Gd ２ O ３ +Ta ２ O ５ + ZnO + WO ３ +GeO ２ ) is 1.0 to 3.0, 2) (TiO ２ +ZnO + Ta ２ O ５ +WO ３ ) / Nb ２ O ５ is between 0.1 and 0.5, 3) (Ta ２ O ５ +ZnO+RO) / TiO ２ is less than or equal to 1.0, 5. The optical glass according to claim 1, wherein the RO is one or more of MgO, CaO, SrO, and BaO.

10. When the composition is expressed as a weight percentage, 1) Y ２ O ３ / (Gd ２ O ３ +Ta ２ O ５ + ZnO + WO ３ +GeO ２ ) is 1.2 to 2.0, 2) (TiO ２ +ZnO + Ta ２ O ５ +WO ３ ) / Nb ２ O ５ is between 0.1 and 0.3, 3) (Ta ２ O ５ +ZnO+RO) / TiO ２ is less than or equal to 0.5; 5. The optical glass according to claim 1, wherein the RO is one or more of MgO, CaO, SrO, and BaO.

11. The composition expressed in weight percentage is SiO ２ : 5% to 10%, and / or B ２ O ３ : 10% to 14%, and / or La ２ O ３ : 46% to 53%, and / or Gd ２ O ３ : 3% to 8%, and / or Y ２ O ３ : 5% to 9.5%, and / or ZrO ２ : 4% to 9%, and / or Nb ２ O ５ : 5.5% to 11%, and / or TiO ２ : 0.5% to 4%, and / or Al ２ O ３ : 0.1% to 3%, and / or ZnO: 0 to 2%, and / or RO: 0 to 3%, and / or Rn ２ O: 0 to 3%, and / or WO ３ : 0 to 3%, and / or Ta ２ O ５ : 0 to 3%, and / or Yb ２ O ３ : 0 to 3%, and / or GeO ２ : 0 to 2%, and / or fining agent: 0 to 0.5%, wherein the RO is one or more of MgO, CaO, SrO, and BaO, and Rn ２ O is Li ２ O, Na ２ O.K. ２ O, and the fining agent is Sb ２ O ３ , SnO ２ , CeO ２ 5. The optical glass according to claim 1, wherein the optical glass is one or more of the following:

12. The composition expressed in weight percentage is SiO ２ : 5.5% to 9%, and / or B ２ O ３ : 11% to 13.5%, and / or La ２ O ３ : 48% to 52%, and / or Gd ２ O ３ : 4% to 7%, and / or Y ２ O ３ : 5.5% to 8.5%, and / or ZrO ２ : 5% to 8%, and / or Nb ２ O ５ : 6% to 10%, and / or TiO ２ : 1% to 3%, and / or Al ２ O ３ : 0.5% to 2%, and / or ZnO: 0 to 1%, and / or RO: 0 to 1%, and / or Rn ２ O: 0 to 1%, and / or WO ３ : 0 to 1%, and / or Ta ２ O ５ : 0 to 1%, and / or Yb ２ O ３ : 0 to 1%, and / or GeO ２ : 0 to 1%, and / or fining agent: 0 to 0.1%, wherein the RO is one or more of MgO, CaO, SrO, and BaO, and Rn ２ O is Li ２ O, Na ２ O.K. ２ O, and the fining agent is Sb ２ O ３ , SnO ２ , CeO ２ 5. The optical glass according to claim 1, wherein the optical glass is one or more of the following:

13. The composition does not contain ZnO, and / or does not contain MgO, and / or does not contain CaO, and / or does not contain SrO, and / or does not contain BaO, and / or does not contain Li ２ Contains no O and / or Na ２ Contains no O and / or K ２ Contains no O and / or WO ３ and / or Ta ２ O ５ and / or Yb ２ O ３ and / or GeO ２ and / or Sb ２ O ３ and / or SnO ２ and / or CeO ２ 5. The optical glass according to claim 1, wherein the optical glass does not contain:

14. The refractive index n of the optical glass ｄ is 1.87 to 1.90, and the Abbe number ν ｄ is 38 to 40.5, and / or the thermal expansion coefficient α －３０／７０℃ is 85 x 10 －７ / K or less, and / or water resistance stability D Ｗ is 2 classes or more, and / or acid resistance stability D Ａ is 2 classes or more, and / or Knoop hardness H Ｋ is 680 x 10 ７ Pa or greater, and / or the relative partial dispersion P ｇ，Ｆ is 0.7000 or less, and / or the relative partial dispersion deviation value ΔP ｇ，Ｆ is −0.0020 or less, and / or the cellularity is level A or more, and / or the degree of striae is level C or more, and / or the density ρ is 5.10 g / cm ３ The optical glass according to any one of claims 1 to 4, characterized in that it has a viscosity of 1000 ppm or less and / or devitrification resistance of level C or higher.

15. The refractive index n of the optical glass ｄ is 1.88 to 1.89, and the Abbe number ν ｄ is 39 to 40, and / or the thermal expansion coefficient α －３０／７０℃ is 75 x 10 －７ / K or less, and / or water resistance stability D Ｗ is one class, and / or acid resistance stability D Ａ is class 1, and / or Knoop hardness H Ｋ is 700 x 10 ７ Pa or greater, and / or the relative partial dispersion P ｇ，Ｆ is 0.6000 or less, and / or the relative partial dispersion deviation value ΔP ｇ，Ｆ is −0.0058 or less, and / or the degree of foaming is Level A ００ and / or the degree of striae is level B or higher, and / or the density ρ is 4.95 g / cm ３ 5. The optical glass according to claim 1, wherein the optical glass has a viscosity of 1000 ppm or less and / or devitrification resistance of Level A.

16. An optical element manufactured from the optical glass according to any one of claims 1 to 4.

17. An optical device comprising the optical glass according to any one of claims 1 to 4.

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