Special dispersion optical glass, glass preforms, optical elements, and optical equipment

Abstract

The present invention provides a special dispersion optical glass, which contains the following components by weight: SiO2: 23-45%, Nb2O5: 20-40%, ZrO2: 2-14%, RO: 1-25%, Rn2O: 0-25%, Ln2O3: 0-20%, where SiO2 / Nb2O5 is 0.65-2.0, RO is the total content of BaO, SrO, CaO, MgO, Rn2O is the total content of Li2O, Na2O, K2O, and Ln2O3 is the total content of La2O3, Gd2O3, Y2O3, Yb2O3. Through rational component design, the special dispersion optical glass obtained by the present invention has a low content of P g,F Value and ΔP g,F The value is relatively low and the chemical stability is excellent.

Description

[Technical Field]

[0001] The present invention relates to optical glass, and more particularly to special dispersion optical glass, and glass preforms, optical elements and optical instruments produced therefrom. [Background technology]

[0002] Optical glass is an important component of optoelectronic products, and in recent years, with the rapid development of optoelectronic products such as smartphones, SLR cameras, and security surveillance, higher requirements have been placed on the performance of optical glass. For example, in order to realize the performance of eliminating or minimizing the residual dispersion of secondary spectrum expected from optical glass in optical design, the relative partial dispersion (P g,F ) and relative partial variance deviation (ΔP g,F ) must be relatively low. In addition, optical glass comes into contact with substances such as acid, alkali, and water during processing, cleaning, and use, so if it does not have good chemical stability, the service life of the optical glass may be shortened.

[0003] Therefore, P g,F value and ΔP g,F Developing optical glasses with relatively low values ​​and excellent chemical stability has become a new challenge for scientific researchers. Summary of the Invention [Problem to be solved by the invention]

[0004] The technical problem that the present invention aims to solve is g,F value and ΔP g,F The object of the present invention is to provide an optical glass having a relatively low value and excellent chemical stability. [Means for solving the problem]

[0005] The technical solutions adopted by the present invention to solve the technical problems are as follows: (1) Special dispersion optical glass containing the following components by weight: SiO2: 23-45%, Nb2O5: 20-40%, ZrO2: 2-14%, RO: 1-25%, Rn2O: 0-25%, Ln2O3: 0-20%, in which SiO2 / Nb2O5 is 0.65-2.0, where RO is the total content of BaO, SrO, CaO, and MgO, Rn2O is the total content of Li2O, Na2O, and K2O, and Ln2O3 is the total content of La2O3, Gd2O3, Y2O3, and Yb2O3. (2) Special dispersion optical glass containing the following components by weight: SiO2: 23-45%, Nb2O5: 20-40%, ZrO2: 2-14%, RO: 1-25%, Rn2O: 0-25%, Ln2O3: 0-20%, where RO is the total content of BaO, SrO, CaO, and MgO, Rn2O is the total content of Li2O, Na2O, and K2O, and Ln2O3 is the total content of La2O3, Gd2O3, Y2O3, and Yb2O3. (3) The special dispersion optical glass according to either (1) or (2), further comprising the following components in weight percent: ZnO: 0-10%, and / or WO3: 0-5%, and / or B2O3: 0-8%, and / or TiO2: 0-5%, and / or Al2O3: 0-5%, and / or Ta2O5: 0-5%, and / or fining agent: 0-1%, wherein the fining agent is one or more of Sb2O3, SnO, SnO2, and CeO2. (4) A special dispersion optical glass containing SiO2, Nb2O5 and alkaline earth metal oxides in weight percent, wherein SiO2 / Nb2O5 is 0.65 to 2.0, and the refractive index n of the special dispersion optical glass is d is 1.68~1.82, Abbe number v d 31~40, P g,F Value is 0.7000 or less, ΔP g,F The value is less than or equal to 0. (5) The special dispersion optical glass according to (4), containing the following components by weight: SiO2: 23-45%, and / or Nb2O5: 20-40%, and / or ZrO2: 2-14%, and / or RO: 1-25%, and / or Rn2O: 0-25%, and / or Ln2O3: 0-20%, and / or ZnO: 0-10%, and / or WO3: 0-5%, and / or B2O3: 0-8%, and / or TiO2: 0-5%. %, and / or Al2O3: 0-5%, and / or Ta2O5: 0-5%, and / or fining agent: 0-1%, wherein RO is the total content of BaO, SrO, CaO, and MgO, Rn2O is the total content of Li2O, Na2O, and K2O, Ln2O3 is the total content of La2O3, Gd2O3, Y2O3, and Yb2O3, and the fining agent is one or more of Sb2O3, SnO, SnO2, and CeO2. (6) Special dispersion optical glass containing the following components in weight percent: SiO2: 23-45%, Nb2O5: 20-40%, ZrO2: 2-14%, RO: 1-25%, Rn2O: 0-25%, Ln2O3: 0-20%, ZnO: 0-10%, WO3: 0-5%, B2O3: 0-8%, TiO2: 0-5%, Al2O3: 0-5%, Ta2O5: 0-5%, and fining agent: 0-1%, where RO is the total content of BaO, SrO, CaO, and MgO, Rn2O is the total content of Li2O, Na2O, and K2O, Ln2O3 is the total content of La2O3, Gd2O3, Y2O3, and Yb2O3, and the fining agent is one or more of Sb2O3, SnO, SnO2, and CeO2. (7) The special dispersion optical glass according to any one of (1) to (6), containing the following components in weight percent: SiO2 / Nb2O5 is 0.75 to 1.8, preferably SiO2 / Nb2O5 is 0.8 to 1.5, and more preferably SiO2 / Nb2O5 is 0.9 to 1.3. (8) The special dispersion optical glass according to any one of (1) to (7), containing the following components in weight percent: Nb2O5 / (BaO+La2O3) is 0.8 to 8.0, preferably Nb2O5 / (BaO+La2O3) is 1.0 to 6.0, more preferably Nb2O5 / (BaO+La2O3) is 1.2 to 4.0, and even more preferably Nb2O5 / (BaO+La2O3) is 1.5 to 3.0. (9) The special dispersion optical glass according to any one of (1) to (8), containing the following components in weight percent: ZnO / (BaO+La2O3) is 2.0 or less, preferably ZnO / (BaO+La2O3) is 0.05 to 1.5, more preferably ZnO / (BaO+La2O3) is 0.08 to 1.0, and even more preferably ZnO / (BaO+La2O3) is 0.1 to 0.5. (10) The special dispersion optical glass according to any one of (1) to (9), containing the following components in weight percent: (CaO+Na2O) / BaO is 0.02 to 8.0, preferably (CaO+Na2O) / BaO is 0.05 to 5.0, more preferably (CaO+Na2O) / BaO is 0.1 to 3.0, and even more preferably (CaO+Na2O) / BaO is 0.2 to 1.0. (11) The special dispersion optical glass according to any one of (1) to (10), containing the following components in weight percent: BaO / (Na2O+Nb2O5) is 0.05 to 0.8, preferably BaO / (Na2O+Nb2O5) is 0.1 to 0.6, more preferably BaO / (Na2O+Nb2O5) is 0.15 to 0.5, and even more preferably BaO / (Na2O+Nb2O5) is 0.2 to 0.4. (12) The special dispersion optical glass according to any one of (1) to (11), containing the following components in weight percent: Li2O / Rn2O is 0.3 to 1.0, preferably Li2O / Rn2O is 0.4 to 0.9, more preferably Li2O / Rn2O is 0.45 to 0.8, and even more preferably Li2O / Rn2O is 0.5 to 0.75. (13) The special dispersion optical glass according to any one of (1) to (12), containing the following components in weight percent: SiO2 / (BaO+ZnO) is 1.0 to 20.0, preferably SiO2 / (BaO+ZnO) is 1.5 to 15.0, more preferably SiO2 / (BaO+ZnO) is 2.0 to 10.0, and even more preferably SiO2 / (BaO+ZnO) is 2.5 to 5.0. (14) The special dispersion optical glass according to any one of (1) to (13), containing the following components in weight percent: B2O3 / SiO2 is 0.3 or less, preferably B2O3 / SiO2 is 0.2 or less, more preferably B2O3 / SiO2 is 0.15 or less, and even more preferably B2O3 / SiO2 is 0.1 or less. (15) The special dispersion optical glass according to any one of (1) to (14), containing the following components in weight percent: SiO2: 28 to 42%, preferably SiO2: 31 to 40%, and / or Nb2O5: 22 to 37%, preferably Nb2O5: 26 to 33%, and / or ZrO2: 3 to 12%, preferably ZrO2: 5 to 10%, and / or RO: 3 to 20%, preferably RO: 6 to 15%, and / or Rn2O: 1 to 20%, preferably Rn2O: 2 to 15%, and / or Ln2O3: 1 to 15%, preferably Ln2O3: 2 to 10%, and / or ZnO: 0.1 to 8%, preferably ZnO: 0.5 to 6%, and / or WO3: 0 to 3%, preferably or WO3: 0-2%, and / or B2O3: 0-4%, preferably B2O3: 0-2%, and / or TiO2: 0-3%, preferably TiO2: 0-2%, and / or Al2O3: 0-2%, preferably Al2O3: 0-1%, and / or Ta2O5: 0-2%, preferably Ta2O5: 0-1%, and / or fining agent: 0-0.5%, wherein RO is the total content of BaO, SrO, CaO, and MgO, Rn2O is the total content of Li2O, Na2O, and K2O, Ln2O3 is the total content of La2O3, Gd2O3, Y2O3, and Yb2O3, and the fining agent is one or more of Sb2O3, SnO, SnO2, and CeO2. (16) The special dispersion optical glass according to any one of (1) to (15), containing the following components in weight percent: BaO: 2 to 18%, preferably BaO: 4 to 15%, more preferably BaO: 5 to 12%, and / or CaO: 0 to 18%, preferably CaO: 0 to 16.5%, more preferably CaO: 0 to 8%, and / or SrO: 0 to 8%, preferably SrO: 0 to 5%, more preferably SrO: 0 to 2%, and / or MgO: 0 to 8%, preferably MgO: 0 to 5%, more preferably MgO: 0 to 2%, and / or Li2O: 1 to 12%, preferably Li2O: 1 to 10%, more preferably Li2O: 1 to 9%, and / or Na2O: 0 to 10%. , preferably Na2O: 0.5 to 8%, more preferably Na2O: 1 to 6%, and / or K2O: 0 to 8%, preferably K2O: 0 to 5%, more preferably K2O: 0 to 4%, and / or La2O3: 0 to 14%, preferably La2O3: 2 to 12%, more preferably La2O3: 4 to 10%, and / or Gd2O3: 0 to 10%, preferably Gd2O3: 0 to 5%, more preferably Gd2O3: 0 to 3%, and / or Y2O3: 0 to 10%, preferably Y2O3: 0 to 5%, more preferably Y2O3: 0 to 3%, and / or Yb2O3: 0 to 10%, preferably Yb2O3: 0 to 5%, more preferably Yb2O3: 0 to 3%. (17) The special dispersion optical glass according to any one of (1) to (16), wherein the components do not contain B2O3, and / or do not contain TiO2, and / or do not contain WO3, and / or do not contain Ta2O5, and / or do not contain SrO, and / or do not contain MgO, and / or do not contain CaO, and / or do not contain Gd2O3, and / or do not contain Y2O3. (18) Refractive index n d is 1.68 to 1.82, preferably 1.70 to 1.80, more preferably 1.71 to 1.79, and even more preferably 1.73 to 1.77, and / or Abbe number v d The special dispersion optical glass according to any one of (1) to (17), wherein is 31 to 40, preferably 32 to 38, and more preferably 33 to 37. (19) P g,Fa value of 0.7000 or less, preferably 0.6500 or less, more preferably 0.6000 or less, and / or ΔP g,F The special dispersion optical glass according to any one of (1) to (18), wherein the value is 0 or less, preferably −0.0010 or less, more preferably −0.0020 or less, and even more preferably −0.0030 or less. (20) The density ρ is 3.80 g / cm 3 or less, preferably 3.70 g / cm 3 or less, more preferably 3.60 g / cm 3 and / or the thermal expansion coefficient α -30 / 70℃ is 100 x 10 -7 / K or less, preferably 90×10 -7 / K or less, preferably 85×10 -7 / K or less, and / or the transition temperature T g is 600°C or less, preferably 590°C or less, more preferably 580°C or less, and even more preferably 570°C or less, and / or λ 80 is 410 nm or less, preferably λ 80 is 400 nm or less, more preferably λ 80 is 395 nm or less, and / or λ5 is 340 nm or less, preferably λ5 is 335 nm or less, more preferably λ5 is 330 nm or less, and / or water resistance stability D W is Class 2 or more, preferably Class 1, and / or acid resistance stability D A is Class 2 or more, preferably Class 1, and / or Knoop hardness H K is 520 x 10 7 Pa or more, preferably 540 × 10 7 Pa or more, preferably 550×10 7 Pa or more, more preferably 570 × 10 7 The special dispersion optical glass according to any one of claims 1 to 19, wherein the refractive index is 1.0 Pa or more. (21) A glass preform produced using the special dispersion optical glass according to any one of (1) to (20). (22) An optical element produced using the special dispersion optical glass according to any one of (1) to (20) or the glass preform according to (21). (23) An optical instrument comprising the special dispersion optical glass according to any one of (1) to (20) or the optical element according to (22). [Effects of the Invention]

[0006] The beneficial effects of the present invention are as follows: By rationally designing the components, the special dispersion optical glass obtained by the present invention has P g,F and ΔP g,F The value is relatively low and the chemical stability is excellent. DETAILED DESCRIPTION OF THE INVENTION

[0007] The following describes in detail embodiments of the special dispersion optical glass according to the present invention, but the present invention is not limited to the embodiments described below and can be practiced by appropriate modifications within the scope of the object of the present invention. Furthermore, although some omissions may be made, the gist of the present invention is not limited by the repetition of the description, and hereinafter the special dispersion optical glass of the present invention may be referred to simply as optical glass or glass.

[0008] [Special dispersion optical glass] The range of each component (ingredient) of the special dispersion optical glass of the present invention is explained below. In this specification, the content and total content of each component are expressed in weight percent (wt%) unless otherwise specified. That is, the content and total content of each component are expressed as weight percent relative to the total weight of the glass material converted into an oxide composition. Here, "converted into an oxide composition" refers to the case where the total weight of the oxide material when the oxides, complex salts, hydroxides, etc. used as raw materials for the optical glass composition of the present invention are decomposed and converted into oxides during melting is taken as 100%.

[0009] Specifically, the numerical ranges set forth herein include upper and lower limits, and the terms "greater than or equal to" and "less than or equal to" include the endpoints, and all integers and fractions subsumed within the range, but are not limited to the specific values ​​set forth when the range is limited. References herein to "and / or" are inclusive, e.g., "A and / or B" means A only, B only, or both A and B.

[0010] <Required and optional ingredients> SiO2 improves the chemical stability of glass, maintains a viscosity suitable for forming molten glass, and reduces corrosion of refractories and platinum containers. In the present invention, 23% or more of SiO2 is added to achieve these effects, preferably 28% or more, and more preferably 31% or more. If the SiO2 content is too high, it becomes difficult to melt the glass and is also disadvantageous in lowering the glass transition temperature. Therefore, in the present invention, the upper limit of the SiO2 content is 45%, preferably 42%, and more preferably 40%.

[0011] Nb2O5 is a highly refractive and highly dispersive component that increases the refractive index and devitrification resistance of the glass, and also contributes to the relative partial dispersion P g,F and the relative partial variance deviation value ΔP g,F In order to achieve this effect, 20% or more of Nb2O5 is added in the present invention, with the lower limit of the Nb2O5 content being preferably 22%, more preferably 26%. If the Nb2O5 content exceeds 40%, the thermal stability and chemical stability of the glass will decrease, and light transmittance will decrease. Therefore, in the present invention, the upper limit of the Nb2O5 content is 40%, preferably 37%, more preferably 33%.

[0012] As a result of extensive experimental research, the inventors have found that in some embodiments of the present invention, by controlling the ratio of the SiO2 content to the Nb2O5 content, SiO2 / Nb2O5, to within the range of 0.65 to 2.0, the optical glass of the present invention can obtain the desired optical constants and can also reduce the P of the glass. g,F value and ΔPg,F It has been found that this can reduce the SiO2 / Nb2O5 ratio and improve the chemical stability of the glass. Therefore, the SiO2 / Nb2O5 ratio is preferably 0.65 to 2.0, more preferably 0.75 to 1.8, even more preferably 0.8 to 1.5, and still more preferably 0.9 to 1.3.

[0013] ZrO2 increases the refractive index of the glass, adjusts the dispersion, and g,F value and ΔP g,F This reduces the ZrO2 content and optimizes the alkali resistance of the glass. To achieve this effect, the present invention contains 2% or more ZrO2, preferably 3% or more ZrO2, and more preferably 5% or more ZrO2. If the ZrO2 content exceeds 14%, the glass becomes more difficult to melt, the melting temperature rises, inclusions are formed inside the glass, and light transmittance decreases. Therefore, the ZrO2 content is 14% or less, preferably 12% or less, and more preferably 10% or less.

[0014] ZnO adjusts the refractive index and dispersion of glass and increases its stability. At the same time, ZnO can lower the high-temperature viscosity and transition temperature of glass, allowing it to melt at a relatively low temperature and increasing the light transmittance of glass. Furthermore, if the ZnO content is too high, the glass becomes more difficult to mold and its crystallization resistance deteriorates. Therefore, the ZnO content is 10% or less, preferably 0.1 to 8%, and more preferably 0.5 to 6%.

[0015] Alkaline earth metal oxides can adjust the optical constants of glass and improve its resistance to devitrification, but if their content is too high, the chemical stability of the glass decreases. Therefore, the total content RO of alkaline earth metal oxides BaO, SrO, CaO, and MgO is 1 to 25%, preferably 3 to 20%, and more preferably 6 to 15%.

[0016] The addition of BaO to the glass of the present invention can improve the devitrification resistance and hardness of the glass and reduce the refractive index, temperature coefficient, and thermal expansion coefficient of the glass. In order to achieve these effects, 2% or more of BaO is added in the present invention, with the BaO content being preferably 4% or more, and more preferably 5% or more. Furthermore, by controlling the BaO content to 18% or less, it is possible to prevent a decrease in chemical stability due to an excessively high BaO content. The BaO content is preferably 15% or less, and more preferably 12% or less.

[0017] In some embodiments of the present invention, the ratio of the SiO2 content to the total content of BaO and ZnO (BaO + ZnO), SiO2 / (BaO + ZnO), is controlled within the range of 1.0 to 20.0, thereby optimizing the glass forming stability and light transmittance of the glass and reducing the thermal expansion coefficient of the glass. Therefore, SiO2 / (BaO + ZnO) is preferably 1.0 to 20.0, more preferably 1.5 to 15.0, even more preferably 2.0 to 10.0, and even more preferably 2.5 to 5.0.

[0018] CaO adjusts the optical constants of the glass and helps improve the workability of the glass, but if the CaO content is too high, the optical constants of the glass will not meet the requirements and the crystallization resistance will be poor. Therefore, the CaO content is 0 to 18%, preferably 0 to 16.5%, and more preferably 0 to 8%. In some embodiments, it is even more preferable that no CaO is contained.

[0019] Although adding SrO to glass can adjust the refractive index and dispersion of the glass, if the content is too high, the chemical stability of the glass decreases and the cost of the glass increases rapidly. Therefore, the SrO content is 0 to 8%, preferably 0 to 5%, and more preferably 0 to 2%. In some embodiments, it is even more preferable that no SrO is contained.

[0020] Although MgO is advantageous in lowering the density and melting temperature of the glass, if the MgO content is too high, the refractive index of the glass will not meet the design requirements, and the crystallization resistance and stability of the glass will decrease. Therefore, the MgO content is 0 to 8%, preferably 0 to 5%, and more preferably 0 to 2%. In some embodiments, it is even more preferable that no MgO is present.

[0021] Alkali metal oxides can lower the glass transition temperature and optimize the meltability of glass, but if their content is too high, the chemical stability and devitrification resistance of the glass will decrease. Therefore, in the present invention, the total content of alkali metal oxides Li2O, Na2O, and K2O, Rn2O, is 25% or less, preferably 1 to 20%, and more preferably 2 to 15%.

[0022] Li2O significantly improves the meltability of glass, increases the solubility of ZrO2 in glass, lowers the glass transition temperature, and adjusts the refractive index of glass, but if its content is too high, it is detrimental to the acid stability and thermal expansion coefficient of the glass. Therefore, in the present invention, the Li2O content is 1 to 12%, preferably 1 to 10%, and more preferably 1 to 9%.

[0023] Although Na2O can improve the meltability of glass and lower the glass transition temperature, if its content exceeds 10%, the chemical stability and weather resistance of the glass will decrease. Therefore, the Na2O content is 0 to 10%, preferably 0.5 to 8%, and more preferably 1 to 6%.

[0024] In some embodiments of the present invention, by controlling the ratio (CaO + Na2O) / BaO, the ratio of the total content of CaO and Na2O (CaO + Na2O) to the content of BaO, to within a range of 0.02 to 8.0, the chemical stability of the optical glass can be improved and the density of the glass can be reduced, which is advantageous for achieving a lighter optical system. Therefore, (CaO + Na2O) / BaO is preferably 0.02 to 8.0, and more preferably 0.05 to 5.0. Furthermore, by controlling (CaO + Na2O) / BaO to within a range of 0.1 to 3.0, the hardness of the glass can be further optimized. Therefore, more preferably, (CaO + Na2O) / BaO is 0.1 to 3.0, and even more preferably, (CaO + Na2O) / BaO is 0.2 to 1.0.

[0025] In some embodiments of the present invention, the ratio of the BaO content to the total content of Na2O and Nb2O5 (Na2O + Nb2O5), BaO / (Na2O + Nb2O5), can be controlled within a range of 0.05 to 0.8 to increase the hardness of the glass and optimize its light transmittance. Therefore, BaO / (Na2O + Nb2O5) is preferably 0.05 to 0.8, more preferably 0.1 to 0.6, even more preferably 0.15 to 0.5, and still more preferably 0.2 to 0.4.

[0026] Although K2O can improve the thermal stability and meltability of glass, if the K2O content exceeds 8%, the devitrification resistance of the glass decreases. Therefore, the upper limit of the K2O content is 8%, preferably 5%, and more preferably 4%.

[0027] As a result of extensive experimental research, the inventors have found that in some embodiments of the present invention, controlling the Li2O / Rn2O ratio within the range of 0.3 to 1.0 optimizes the devitrification resistance of the glass and improves its water resistance. Therefore, Li2O / Rn2O is preferably 0.3 to 1.0, and more preferably 0.4 to 0.9. Furthermore, controlling the Li2O / Rn2O ratio within the range of 0.45 to 0.8 is also advantageous in improving the weather resistance of the glass. Therefore, Li2O / Rn2O is more preferably 0.45 to 0.8, and even more preferably 0.5 to 0.75.

[0028] Ln2O3 (Ln2O3 is the total content of La2O3, Gd2O3, Y2O3, and Yb2O3) can increase the refractive index of glass, but if its content exceeds 20%, the devitrification resistance of the glass decreases. Therefore, the Ln2O3 content is 20% or less, preferably 1 to 15%, and more preferably 2 to 10%.

[0029] La2O3 effectively improves the refractive index of glass, strengthens the chemical stability and mechanical strength of glass, and at the same time, reduces the P content of glass. g,F value and ΔP g,F Although the value is not significantly increased, if the content exceeds 14%, the devitrification resistance of the glass deteriorates. Therefore, in the glass of the present invention, the La2O3 content is 0 to 14%, preferably 2 to 12%, and more preferably 4 to 10%.

[0030] As a result of extensive experimental research, the inventors have found that in some embodiments of the present invention, the ratio of the Nb2O5 content to the total content of BaO and La2O3 (BaO+La2O3), Nb2O5 / (BaO+La2O3), can be controlled within a range of 0.8 to 8.0, thereby making it possible to obtain glass P g,F value and ΔP g,FIt has been found that this reduces the thermal expansion coefficient of the glass and optimizes the crystallization resistance of the glass during secondary press molding. Therefore, Nb2O5 / (BaO+La2O3) is preferably 0.8 to 8.0, more preferably 1.0 to 6.0, even more preferably 1.2 to 4.0, and still more preferably 1.5 to 3.0.

[0031] In some embodiments of the present invention, a decrease in glass hardness can be prevented by controlling the ratio of the ZnO content to the total content of BaO and La2O3 (BaO + La2O3), ZnO / (ZnO / (BaO + La2O3)), to 2.0 or less. Therefore, ZnO / (BaO + La2O3) is preferably 2.0 or less, and ZnO / (BaO + La2O3) is more preferably 0.05 to 1.5. Furthermore, by controlling ZnO / (BaO + La2O3) to within a range of 0.08 to 1.0, the crystallization resistance and abrasion resistance of the glass can be further optimized, and an increase in the thermal expansion coefficient of the glass can be prevented. Therefore, ZnO / (BaO + La2O3) is more preferably 0.08 to 1.0, and even more preferably ZnO / (BaO + La2O3) is 0.1 to 0.5.

[0032] Although Gd2O3 can increase the refractive index, if its content exceeds 10%, the devitrification resistance of the glass decreases and the transition temperature tends to increase. Therefore, the Gd2O3 content in the present invention is 10% or less, preferably 0 to 5%, and more preferably 0 to 3%. In some embodiments, it is even more preferable that no Gd2O3 is contained.

[0033] Y2O3 can improve the meltability and crystallization resistance of glass and increase the chemical stability of glass, but if its content exceeds 10%, the stability and devitrification resistance of glass decrease. Therefore, the Y2O3 content should be 0 to 10%, preferably 0 to 5%, more preferably 0 to 3%, and even more preferably no Y2O3.

[0034] Although Yb2O3 can increase the refractive index of glass, if its content exceeds 10%, the stability and devitrification resistance of the glass decrease. Therefore, the Yb2O3 content should be 0 to 10%, preferably 0 to 5%, more preferably 0 to 3%, and even more preferably no Yb2O3.

[0035] Although WO3 can increase the refractive index and mechanical strength of glass, a WO3 content exceeding 5% reduces the thermal stability of the glass, resulting in reduced transmittance and devitrification resistance. Therefore, the upper limit of the WO3 content is 5%, preferably 3%, and more preferably 2%. In some embodiments, it is even more preferable to have no WO3.

[0036] B2O3 can function as a glass network former in the glasses of the present invention, and g,F value and ΔP g,F This is advantageous for reducing the glass's porosity. If the B2O3 content exceeds 8%, the chemical stability of the glass deteriorates, the high-temperature viscosity of the glass decreases, and the glass transmittance and crystallization resistance during secondary press molding deteriorate. Therefore, the B2O3 content is limited to 8% or less, preferably 4% or less, and more preferably 2% or less. In some embodiments, it is even more preferable that the glass does not contain B2O3.

[0037] In some embodiments of the present invention, controlling the B2O3 / SiO2 ratio to 0.3 or less can improve the crystallization resistance and chemical stability of the glass. Therefore, B2O3 / SiO2 is preferably 0.3 or less, and more preferably 0.2 or less. Furthermore, controlling the B2O3 / SiO2 ratio to 0.15 or less is advantageous in improving the hardness of the glass. Therefore, B2O3 / SiO2 is more preferably 0.15 or less, and even more preferably 0.1 or less.

[0038] TiO2 has the effect of increasing the refractive index and dispersion of glass, and adding an appropriate amount can make glass more stable and reduce the viscosity of glass. However, the presence of TiO2 affects the P g,F value and ΔPg,F Therefore, the content of TiO2 in the present invention is 5% or less, preferably 3% or less, and more preferably 2% or less. In some embodiments, it is even more preferable that TiO2 is not present.

[0039] Although Al2O3 can improve the chemical stability of glass, if its content exceeds 5%, the meltability and light transmittance of the glass deteriorate. Therefore, in the present invention, the Al2O3 content is 0 to 5%, preferably 0 to 2%, and more preferably 0 to 1%. In some embodiments, it is even more preferable that Al2O3 is not contained.

[0040] Ta2O5 increases the refractive index of the glass and g,F value and ΔP g,F However, if the Ta2O5 content is too high, the chemical stability of the glass decreases, the surface tension of the glass increases, and it becomes difficult to remove bubbles. Furthermore, Ta2O5 is very expensive compared to other components, and from a practical and cost-effective standpoint, it is necessary to reduce its use as much as possible. Therefore, in the present invention, the Ta2O5 content is limited to 0 to 5%, preferably 0 to 2%, more preferably 0 to 1%, and even more preferably, Ta2O5 is not present.

[0041] In the present invention, the fining effect of glass can be enhanced by adding 0-1% of one or more of Sb2O3, SnO, SnO2, and CeO2 as a fining agent. The fining agent content is preferably 0-0.5%. If the Sb2O3 content exceeds 1%, the fining ability of the glass tends to decrease, and its strong oxidizing effect promotes corrosion of platinum or platinum alloy glass-melting containers and deterioration of forming dies. Therefore, the Sb2O3 content in the present invention is preferably 0-1%, more preferably 0-0.5%. SnO and SnO2 can also be used as fining agents, but if their content exceeds 1%, the glass tends to become more colored. When the glass is heated, softened, and reshaped by press molding, Sn acts as a starting point for crystal nucleation, leading to devitrification. Therefore, the SnO2 content in the present invention is preferably 0-1%, more preferably 0-0.5%, and the SnO content is preferably 0-1%, more preferably 0-0.5%. The function and content ratio of CeO2 are the same as those of SnO2, and the content thereof is preferably 0 to 1%, more preferably 0 to 0.5%, and even more preferably does not contain CeO2.

[0042] <Ingredients that should not be included>

[0043] 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, the glass is colored and specific wavelengths in the visible light region are absorbed, weakening the visible light transmission effect of the present invention. Therefore, it is preferable that optical glasses that require wavelength transmittance in the visible light region in particular do not actually contain these oxides.

[0044] In recent years, there has been a trend toward restricting the use of oxides of Th, Cd, Tl, Os, Be, and Se as hazardous chemicals, necessitating environmental protection efforts not only in the glass manufacturing process but also in the processing and disposal of finished products. Therefore, when environmental impact is a major concern, it is preferable to avoid these elements except for unavoidable contamination. This ensures that the optical glass does not contain substances that actually pollute the environment. Therefore, the optical glass of the present invention can be manufactured, processed, and disposed of without the need for special environmental measures.

[0045] In consideration of the environment, the optical glass of the present invention preferably does not contain As2O3 and PbO.

[0046] The terms "not added," "not containing," and "0%" used herein mean that the component was not intentionally added as a raw material for the glass of the present invention. However, impurities or components not intentionally added as raw materials and / or equipment for producing the glass may exist in small or trace amounts in the final glass, and these are also within the scope of the present invention.

[0047] The performance of the special dispersion optical glass of the present invention will now be described.

[0048] <Refractive index and Abbe number> The refractive index of optical glass (n d ) and Abbe number (ν d ) has been tested in accordance with the method specified in GB / T 7962.1-2010.

[0049] In some embodiments, the refractive index (n d The lower limit of the refractive index (n d ) is 1.82, preferably 1.80, more preferably 1.79, and even more preferably 1.77.

[0050] In some embodiments, the Abbe number (ν d The lower limit of the Abbe number (ν ) of the special dispersion optical glass of the present invention is 31, preferably 32, and more preferably 33. In some embodiments, the lower limit of the Abbe number (ν d ) has an upper limit of 40, preferably 38, and more preferably 37.

[0051] <density> The density (ρ) of optical glass is tested according to the method described in GB / T 7962.20-2010.

[0052] In some embodiments, the density (ρ) of the special dispersion optical glass of the present invention is 3.80 g / cm 3 or less, preferably 3.70 g / cm 3 or less, more preferably 3.60 g / cm 3 The following is the result.

[0053] <Thermal expansion coefficient> The thermal expansion coefficient of optical glass (α -30 / 70℃ ) is measured at -30 to 70°C according to the method described in GB / T 7962.16-2010.

[0054] In some embodiments, the thermal expansion coefficient (α -30 / 70℃ ) is 100 x 10 -7 / K or less, preferably 90×10 -7 / K or less, preferably 85×10 -7 / K or less.

[0055] <Transition temperature> Optical glass transition temperature (T g ) is measured according to the method specified in GB / T 7962.16-2010.

[0056] In some embodiments, the transition temperature (T g) is 600°C or less, preferably 590°C or less, more preferably 580°C or less, and further preferably 570°C or less.

[0057] <Coloring degree> The short-wave transmission spectrum characteristics of the glass of the present invention are determined by the coloring degree (λ 80 and λ5). 80 λ refers to the wavelength at which the glass transmittance reaches 80%. 80 In the measurement, a glass with a thickness of 10±0.1 mm having two parallel, optically polished flat surfaces is used, and the spectral transmittance is measured in the wavelength range from 280 nm to 700 nm, and the wavelength at which the transmittance is 80% is shown. Spectral transmittance or transmittance is the intensity I in The light is incident on the glass and passes through it with an intensity of I out When light of I is emitted from one plane, out / I in This quantity is expressed by the formula λ , and includes the transmittance of the surface reflection loss at the surface of the glass. The higher the refractive index of the glass, the greater the surface reflection loss. Therefore, for high refractive index glass, λ 80 The smaller the value, the less coloring there is in the glass itself and the higher the light transmittance.

[0058] In some embodiments, the λ 80 is 410 nm or less, preferably λ 80 is 400 nm or less, more preferably λ 80 is 395 nm or less.

[0059] In some embodiments, the special dispersion optical glass of the present invention has a λ5 of 340 nm or less, preferably a λ5 of 335 nm or less, and more preferably a λ5 of 330 nm or less.

[0060] <Water resistance stability> Water resistance stability of optical glass (D W ) (powder method) is tested according to the method specified in GB / T 17129.

[0061] In some embodiments, the water resistance stability (D W ) is class 2 or more, preferably class 1.

[0062] <Acid resistance stability> Acid resistance stability of optical glass (D A ) (powder method) is tested according to the method specified in GB / T 17129.

[0063] In some embodiments, the acid resistance stability (D A ) is class 2 or more, preferably class 1.

[0064] <Knoop hardness> Knoop hardness of optical glass (H K ) has been tested in accordance with the test method specified in GB / T 7962.18-2010.

[0065] In some embodiments, the Knoop hardness (H k ) is 520 x 10 7 Pa or more, preferably 540 × 10 7 Pa or more, preferably 550×10 7 Pa or more, more preferably 570 × 10 7 Pa or more.

[0066] <Relative partial variance and relative partial variance deviation> The relative partial variance (P g,F ) and relative partial variance deviation (ΔP g,F ) Explain the origin of the word. The relative partial dispersion for wavelengths x and y is given by the following equation (1): P x,y =(n x -n y ) / (n F -n C ) (1)

[0067] According to Abbe's formula, the following formula (2) holds true for most so-called "normal glasses" (hereinafter, H-K6 and F4 will be referred to as "normal glasses"). P x,y =m x,y ·v d +b x,y (2) This linear relationship is x,y is the ordinate, v d is expressed as the abscissa, and in the formula, m x,y is the slope, b x,y is the intercept.

[0068] As is well known, to correct for secondary spectra, i.e., to eliminate color differences for two or more wavelengths, it is necessary to select at least one glass that does not conform to the above formula (2) (i.e., its P x,y The deviation value is ΔP x,y When expressed as x,y -v d The point is the "normal line" that corresponds to the above equation (2) x,y In this way, the ΔP of each glass x,y The value can be calculated using the following formula (3): P x,y =m x,y ·v d +b x,y +ΔP x,y (3) Therefore, ΔP x,y quantitatively expresses the deviation characteristics of the special dispersion compared to "normal glass".

[0069] Therefore, as mentioned above, the relative partial variance (P g,F ) and relative partial variance deviation (ΔP g,F ) are calculated using the following equations (4) and (5): P g,F =(n g -n F ) / (n F -n C ) (4) ΔP g,F =P g,F -0.6457+0.001703vd (5)

[0070] In some embodiments, the relative partial dispersion (P g,F ) is 0.7000 or less, preferably 0.6500 or less, and more preferably 0.6000 or less.

[0071] In some embodiments, the relative partial dispersion deviation value (ΔP g,F ) is 0 or less, preferably −0.0010 or less, more preferably −0.0020 or less, and even more preferably −0.0030 or less.

[0072] <Crystallization resistance> The crystallization resistance test method is as follows: A sample glass was cut into a size of 20 x 20 x 10 mm, and g The glass is placed in a muffle furnace at +(200-250)°C and kept at this temperature for 15-30 minutes. After removal and cooling, the glass is observed for the presence of crystals on the surface and inside, and for the development of opacity. The absence of opacity and crystals in the glass sample indicates excellent crystallization resistance. This test method is used to characterize the crystallization resistance of the glass of the present invention during secondary pressing.

[0073] [Manufacturing method of special dispersion optical glass] The method for producing the special dispersion optical glass of the present invention is as follows: After mixing common raw materials, including but not limited to oxides, hydroxides, carbonates, nitrates, phosphates, and metaphosphates, using conventional processes, the resulting furnace material is placed in a melting furnace (platinum or platinum alloy crucible) at 1200°C to 1400°C and melted. The mixture is then refined and homogenized to obtain a homogeneous molten glass free of bubbles and undissolved materials, which is then cast into a mold and annealed. Those skilled in the art will be able to select the appropriate raw materials, production methods, and process parameters according to actual needs.

[0074] [Glass preforms and optical elements] Glass preforms can be manufactured from special dispersion optical glass produced using direct drop molding or polishing, or press molding such as hot press molding. That is, molten optical glass can be produced into a precision glass preform by direct precision drop molding, or a glass preform can be produced by mechanical processing such as grinding or polishing, or a preform blank for press molding can be produced using optical glass, and this preform blank can be hot pressed and polished to produce a glass preform. It should be noted that the means for manufacturing optical preforms are not limited to the above means.

[0075] As described above, the special dispersion optical glass of the present invention is useful for a variety of optical elements and optical designs, and it is particularly preferable to form a preform from the special dispersion optical glass of the present invention and use this preform to carry out reheat press molding, precision press molding, or the like to produce optical elements such as lenses and prisms.

[0076] The glass preform and optical element of the present invention are both formed from the special dispersion optical glass of the present invention. The glass preform of the present invention has the excellent properties of special dispersion optical glass, and the optical element of the present invention has the excellent properties of special dispersion optical glass, making it possible to provide optical elements such as various lenses and prisms with high optical value.

[0077] Examples of lenses include various lenses such as a concave meniscus lens, a convex meniscus lens, a biconvex lens, a biconcave lens, a plano-convex lens, and a plano-concave lens, each having a spherical or aspherical lens surface.

[0078] [Optical equipment] Optical elements formed from the special dispersion optical glass of the present invention can be used to manufacture optical equipment such as photographic devices, imaging devices, projection devices, display devices, in-vehicle devices, and monitoring devices. [Example]

[0079] <Optical Glass Examples> To further clearly illustrate the technical solutions of the present invention, the following non-limiting examples are provided.

[0080] In this example, optical glasses having the components shown in Tables 1 to 5 are obtained using the above-mentioned method for producing special dispersion optical glass. The properties of each glass were measured using the test methods described in the present invention, and the results are shown in Tables 1 to 5. In the crystallization resistance tests in Tables 1 to 5, according to the test method, glasses that are free of milkiness and have no crystalline particles inside are marked with an "A," glasses that are free of milkiness but have 1 to 10 crystalline particles inside are marked with a "B," glasses that are free of milkiness but have 10 to 20 crystalline particles inside are marked with a "C," and glasses that have milkiness or have densely packed precipitated particles inside are marked with an "X."

[0081] [Table 1] [Table 2] [Table 3] [Table 4] [Table 5]

[0082] <Example of glass preform> The special dispersion optical glass obtained in Examples 1 to 32 is subjected to polishing or press molding such as reheat press molding or precision press molding to produce preforms of various lenses such as concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, and plano-concave lenses, as well as prisms.

[0083] <Optical element examples> These preforms obtained in the glass preform examples above 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.

[0084] Each preform is then ground and polished to produce various lenses and prisms, including concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, and plano-concave lenses.Anti-reflection coatings can also be applied to the surfaces of the resulting optical elements.

[0085] <Optical equipment example> The optical elements manufactured according to the above optical element embodiments can be used in imaging devices, sensors, microscopes, medical technology, digital projection, communications, optical communication technology / information transmission, optics / illumination in the automotive field, photolithography technology, excimer lasers, wafers, computer chips and integrated circuits and electronic devices containing such circuits and chips, by using one or more optical elements according to optical design to form optical parts or components.

Claims

1. Special dispersion optical glass containing the following components in weight percent: SiO ２ :23-45%, Nb ２ O ５ :20~40%, ZrO ２ :2~14%, RO:1~25%, Rn ２ O: 0-25%, Ln ２ O ３ :0~20%, ZnO:0.1~10%, TiO ２ : 0-5%, B ２ O ３ : 0 to 4%, of which SiO ２ / Nb ２ O ５ is 0.65 to 2.0, Nb ２ O ５ / (BaO+La ２ O ３ ) is 0.8 to 4.0, ZnO / (BaO+La ２ O ３ ) is 0.1 to 2.0, the RO is the total content of BaO, SrO, CaO, and MgO, and Rn ２ O is Li ２ O, Na ２ O.K. ２ is the total content of O, and Ln ２ O ３ Is La ２ O ３ , Gd ２ O ３ , Y ２ O ３ , Yb ２ O ３ The total content is

2. 2. The special dispersion optical glass of claim 1, further comprising the following components in weight percent: WO ３ : 0 to 5%, and / or Al ２ O ３ : 0 to 5%, and / or Ta ２ O ５ : 0 to 5%, and / or fining agent: 0 to 1%, the fining agent being Sb ２ O ３ , SnO, SnO ２ , CeO ２ It is one or more of the following.

3. SiO in wt% ２ , Nb ２ O ５ and alkaline earth metal oxides, of which ZnO: 0.1 to 10%, TiO ２ : 0-5%, B ２ O ３ : 0 to 4%, SiO ２ / Nb ２ O ５ is 0.65 to 2.0, Nb ２ O ５ / (BaO+La ２ O ３ ) is 0.8 to 4.0, ZnO / (BaO+La ２ O ３ ) is 0.1 to 2.0, the refractive index n ｄ is 1.68 to 1.82, Abbe number v ｄ 31-40, P ｇ，Ｆ Value is 0.7000 or less, ΔP ｇ，Ｆ The value is less than or equal to 0.

4. 4. The special dispersion optical glass of claim 3, further comprising the following components in weight percent: SiO ２ : 23 to 45%, and / or Nb ２ O ５ : 20 to 40%, and / or ZrO ２ : 2 to 14%, and / or RO: 1 to 25%, and / or Rn ２ O: 0 to 25%, and / or Ln ２ O ３ : 0 to 20%, and / or WO ３ : 0 to 5%, and / or Al ２ O ３ : 0 to 5%, and / or Ta ２ O ５ : 0 to 5%, and / or fining agent: 0 to 1%, wherein RO is the total content of BaO, SrO, CaO, and MgO, and Rn ２ O is Li ２ O, Na ２ O.K. ２ is the total content of O, and Ln ２ O ３ Is La ２ O ３ , Gd ２ O ３ , Y ２ O ３ , Yb ２ O ３ The total content of the fining agent is Sb ２ O ３ , SnO, SnO ２ , CeO ２ It is one or more of the following.

5. 5. The special dispersion optical glass according to claim 1, which contains the components in weight percent and satisfies one or more of the following six conditions: 1) SiO ２ / Nb ２ O ５ is 0.75 to 1.8; 2) (CaO + Na ２ O) / BaO is 0.02 to 8.0; 3) BaO / (Na ２ O+Nb ２ O ５ ) is 0.05 to 0.8; 4) Li ２ O / Rn ２ O is 0.3 to 1.0; 5) SiO ２ / (BaO + ZnO) is 1.0 to 20.0; 6) B ２ O ３ / SiO ２ is 0.3 or less.

6. 5. The special dispersion optical glass according to claim 1, which contains the components in weight percent and satisfies one or more of the following eight conditions: 1) SiO ２ / Nb ２ O ５ is 0.9 to 1.3; 2) Nb ２ O ５ / (BaO+La ２ O ３ ) is 1.2 to 4.0; 3) ZnO / (BaO+La ２ O ３ ) is 0.1 to 1.0; 4) (CaO + Na ２ O) / BaO is 0.1 to 3.0; 5) BaO / (Na ２ O+Nb ２ O ５ ) is 0.15 to 0.5; 6) Li ２ O / Rn ２ O is 0.45 to 0.8; 7) SiO ２ / (BaO + ZnO) is 2.0 to 10.0; 8) B ２ O ３ / SiO ２ is 0.15 or less.

7. 5. The special dispersion optical glass according to claim 1, which contains the components in weight percent and satisfies one or more of the following eight conditions: 1) SiO ２ / Nb ２ O ５ is between 1.102 and 1.255; 2) Nb ２ O ５ / (BaO+La ２ O ３ ) is 1.5 to 2.364; 3) ZnO / (BaO+La ２ O ３ ) is 0.1 to 0.331; 4) (CaO + Na ２ O) / BaO is 0.357 to 0.857; 5) BaO / (Na ２ O+Nb ２ O ５ ) is 0.2 to 0.313; 6) Li ２ O / Rn ２ O is 0.5 to 0.75; 7) SiO ２ / (BaO + ZnO) is 2.774 to 4.09; 8) B ２ O ３ / SiO ２ is 0.1 or less.

8. The special dispersion optical glass according to any one of claims 1 to 4, comprising the following components in weight percent: SiO ２ : 28 to 42%, and / or Nb ２ O ５ : 22 to 37%, and / or ZrO ２ : 3 to 12%, and / or RO: 3 to 20%, and / or Rn ２ O: 1 to 20%, and / or Ln ２ O ３ : 1 to 15%, and / or ZnO: 0.1 to 8%, and / or WO ３ : 0 to 3%, and / or TiO ２ : 0 to 3%, and / or Al ２ O ３ : 0 to 2%, and / or Ta ２ O ５ : 0 to 2%, and / or fining agent: 0 to 0.5%, wherein RO is the total content of BaO, SrO, CaO, and MgO, and Rn ２ O is Li ２ O, Na ２ O.K. ２ is the total content of O, and Ln ２ O ３ Is La ２ O ３ , Gd ２ O ３ , Y ２ O ３ , Yb ２ O ３ The total content of the fining agent is Sb ２ O ３ , SnO, SnO ２ , CeO ２ It is one or more of the following.

9. The special dispersion optical glass according to any one of claims 1 to 4, comprising the following components in weight percent: SiO ２ : 31 to 40%, and / or Nb ２ O ５ : 26 to 33%, and / or ZrO ２ : 5 to 10%, and / or RO: 6 to 15%, and / or Rn ２ O: 2 to 15%, and / or Ln ２ O ３ : 2 to 10%, and / or ZnO: 0.5 to 6%, and / or WO ３ : 0 to 2%, and / or B ２ O ３ : 0 to 2%, and / or TiO ２ : 0 to 2%, and / or Al ２ O ３ : 0 to 1%, and / or Ta ２ O ５ : 0 to 1%, wherein RO is the total content of BaO, SrO, CaO, and MgO, and Rn ２ O is Li ２ O, Na ２ O.K. ２ is the total content of O, and Ln ２ O ３ Is La ２ O ３ , Gd ２ O ３ , Y ２ O ３ , Yb ２ O ３ The total content of the fining agent is Sb ２ O ３ , SnO, SnO ２ , CeO ２ It is one or more of the following.

10. The special dispersion optical glass according to any one of claims 1 to 4, comprising the following components in weight percent: BaO: 2 to 18%, and / or SrO: 0 to 8%, and / or MgO: 0 to 8%, and / or Li ２ O: 1 to 12%, and / or Na ２ O: 0 to 10% and / or K ２ O: 0 to 8%, and / or La ２ O ３ : 0 to 14%, and / or Gd ２ O ３ : 0 to 10%, and / or Y ２ O ３ : 0 to 10%, and / or Yb ２ O ３ : 0 to 10%.

11. The special dispersion optical glass according to any one of claims 1 to 4, comprising the following components in weight percent: BaO: 5 to 12%, and / or SrO: 0 to 2%, and / or MgO: 0 to 2%, and / or Li ２ O: 1 to 9% and / or Na ２ O: 1 to 6%, and / or K ２ O: 0 to 4%, and / or La ２ O ３ : 4 to 10%, and / or Gd ２ O ３ : 0 to 3%, and / or Y ２ O ３ : 0 to 3%, and / or Yb ２ O ３ : 0 to 3%.

12. The component B ２ O ３ and / or TiO ２ and / or WO ３ and / or Ta ２ O ５ and / or does not contain SrO, and / or does not contain MgO, and / or does not contain CaO, and / or Gd ２ O ３ and / or does not contain Y ２ O ３ The special dispersion optical glass according to any one of claims 1 to 4, which does not contain

13. The refractive index n of the special dispersion optical glass ｄ is 1.70 to 1.80, and / or Abbe number v ｄ is 31 to 40, and / or P ｇ，Ｆ value is 0.7000 or less, and / or ΔP ｇ，Ｆ value is −0.0010 or less, and / or density ρ is 3.80 g / cm ３ and / or the thermal expansion coefficient α －３０／７０℃ is 100 x 10 －７ / K or less, and / or the transition temperature T ｇ is 600°C or less, and / or λ ８０ is 410 nm or less, and / or λ ５ is 340 nm or less, and / or water resistance stability D Ｗ Class 2 or higher, and / or acid resistance stability D Ａ Class 2 or higher, and / or Knoop hardness H Ｋ is 540 x 10 ７ The special dispersion optical glass according to any one of claims 1 to 4, wherein the refractive index is 0.01 Pa or more.

14. The refractive index n of the special dispersion optical glass ｄ is 1.73 to 1.77, and / or Abbe number v ｄ is 33 to 37, and / or P ｇ，Ｆ value is 0.6000 or less, and / or ΔP ｇ，Ｆ value is −0.0030 or less, and / or density ρ is 3.60 g / cm ３ and / or the thermal expansion coefficient α －３０／７０℃ is 85 x 10 －７ / K or less, and / or the transition temperature T ｇ is 580°C or less, and / or λ ８０ is 395 nm or less, and / or λ ５ is 330 nm or less, and / or water resistance stability D Ｗ Class 1 or higher, and / or acid resistance stability D Ａ is Class 1 or higher, and / or Knoop hardness H Ｋ is 570 x 10 ７ The special dispersion optical glass according to any one of claims 1 to 4, wherein the refractive index is 0.01 Pa or more.

15. A glass preform manufactured using the special dispersion optical glass according to any one of claims 1 to 4.

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

17. An optical instrument comprising the special dispersion optical glass according to any one of claims 1 to 4.

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