Optical glass, glass preforms, optical elements and optical equipment

Abstract

To provide an optical glass that has a refractive index of 1.90-1.97 and an Abbe number of 24-32, featuring superior chemical stability.SOLUTION: An optical glass provided includes, in wt.%, following components: SiO2: 2-15%, B2O3: 5-20%, La2O3: 25-45%, ZrO2: 1-12%, TiO2: 7-22%, Nb2O5: 5-20%, and RO: 7-35%, where the RO denotes a total content of MgO, CaO, SrO, and BaO. The inventive optical glass features a rational component design, allowing for achievement of a desired refractive index and Abbe number, as well as superior chemical stability.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to optical glass, and more particularly to optical glass having a refractive index of 1.90 to 1.97 and an Abbe number of 24 to 32, as well as a glass preform, optical element and optical instrument made therefrom. [Background technology]

[0002] With the fusion of optics, electronic information science, and new materials science, the applications of optical glass, which is the basic material for optoelectronics, in the fields of optical transmission, optical storage, and photoelectric display are expanding dramatically. In recent years, optical elements and optical equipment have rapidly developed in terms of digitalization, integration, and high definition, which has placed higher requirements on the performance of optical equipment and the optical glass used in them.

[0003] Optical glass with a refractive index of 1.90 to 1.97 and an Abbe number of 24 to 32 is of great significance for simplifying optical systems and improving imaging quality in the fields of optical design and optical communications. Conventional optical glass has a relatively low chemical stability, making it susceptible to damage when exposed to substances such as acid, alkali, and water during processing or use, shortening the service life of the optical glass. Summary of the Invention [Problem to be solved by the invention]

[0004] The technical problem to be solved by the present invention is to provide an optical glass having a refractive index of 1.90 to 1.97, an Abbe number of 24 to 32, 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:

[0006] Optical glass containing the following components in weight percent: SiO2: 2-15%, B2O3: 5-20%, La2O3: 25-45%, ZrO2: 1-12%, TiO2: 7-22%, Nb2O5: 5-20%, RO: 7-35%, where RO is the total content of MgO, CaO, SrO, and BaO.

[0007] The optical glass further contains the following components in weight percent: Y2O3: 0-8%, and / or Gd2O3: 0-8%, and / or Yb2O3: 0-5%, and / or ZnO: 0-8%, and / or Rn2O: 0-8%, and / or GeO2: 0-5%, and / or WO3: 0-5%, and / or Ta2O5: 0-8%, and / or Al2O3: 0-5%, and / or a fining agent: 0-1%, wherein the Rn2O is one or more of Li2O, Na2O, and K2O, and the fining agent is one or more of Sb2O3, SnO, SnO2, and CeO2.

[0008] Optical glass containing the following components by weight: SiO2: 2-15%, B2O3: 5-20%, La2O3: 25-45%, ZrO2: 1-12%, TiO2: 7-22%, Nb2O5: 5-20%, RO: 7-35%, Y2O3: 0-8%, Gd2O3: 0-8%, Yb2O3: 0-5%, ZnO: 0-8%, Rn2O: 0-8% %, GeO2: 0-5%, WO3: 0-5%, Ta2O5: 0-8%, Al2O3: 0-5%, fining agent: 0-1%, where RO is the total content of MgO, CaO, SrO, and BaO, Rn2O is one or more of Li2O, Na2O, and K2O, and the fining agent is one or more of Sb2O3, SnO, SnO2, and CeO2.

[0009] Furthermore, the optical glass contains the following components in weight percent: CaO / (SiO2+ZrO2) is 0.01 to 2.0, preferably CaO / (SiO2+ZrO2) is 0.02 to 1.5, more preferably CaO / (SiO2+ZrO2) is 0.05 to 1.0, and even more preferably CaO / (SiO2+ZrO2) is 0.08 to 0.7.

[0010] The optical glass further contains the following components in weight percent: (B2O3+SrO) / (CaO+BaO+TiO2) is 0.1 to 1.0, preferably (B2O3+SrO) / (CaO+BaO+TiO2) is 0.1 to 0.8, more preferably (B2O3+SrO) / (CaO+BaO+TiO2) is 0.2 to 0.6, and even more preferably (B2O3+SrO) / (CaO+BaO+TiO2) is 0.25 to 0.5.

[0011] Furthermore, the optical glass contains the following components in weight percent: (Gd2O3+Y2O3+Ta2O5) / TiO2 is 1.0 or less, preferably (Gd2O3+Y2O3+Ta2O5) / TiO2 is 0.8 or less, more preferably (Gd2O3+Y2O3+Ta2O5) / TiO2 is 0.5 or less, and even more preferably (Gd2O3+Y2O3+Ta2O5) / TiO2 is 0.2 or less.

[0012] The optical glass further contains the following components in weight percent: (SiO2+BaO) / (La2O3+Nb2O5) is 0.2 to 1.0, preferably (SiO2+BaO) / (La2O3+Nb2O5) is 0.25 to 0.9, more preferably (SiO2+BaO) / (La2O3+Nb2O5) is 0.3 to 0.8, and even more preferably (SiO2+BaO) / (La2O3+Nb2O5) is 0.4 to 0.6.

[0013] The optical glass further contains the following components in weight percent: the content of B2O3 is higher than the content of SiO2, and / or (SiO2+Nb2O5) / (B2O3+La2O3) is 0.15 to 1.0, preferably (SiO2+Nb2O5) / (B2O3+La2O3) is 0.2 to 0.8, more preferably (SiO2+Nb2O5) / (B2O3+La2O3) is 0.25 to 0.65, and even more preferably (SiO2+Nb2O5) / (B2O3+La2O3) is 0.3 to 0.5.

[0014] The optical glass further contains the following components in weight percent: ZnO / CaO is 2.0 or less, preferably ZnO / CaO is 1.5 or less, more preferably ZnO / CaO is 1.0 or less, and even more preferably ZnO / CaO is 0.5 or less.

[0015] The optical glass further contains the following components in weight percent: RO / Nb2O5 is 0.5 to 5.0, preferably RO / Nb2O5 is 0.6 to 3.0, more preferably RO / Nb2O5 is 0.8 to 2.5, and even more preferably RO / Nb2O5 is 1.0 to 2.0, where RO is the total content of MgO, CaO, SrO, and BaO.

[0016] The optical glass further contains the following components in weight percent: (La2O3+Gd2O3+Y2O3) / RO is 0.8 to 5.0, preferably (La2O3+Gd2O3+Y2O3) / RO is 1.0 to 4.0, more preferably (La2O3+Gd2O3+Y2O3) / RO is 1.2 to 3.0, and even more preferably (La2O3+Gd2O3+Y2O3) / RO is 1.5 to 2.5, where RO is the total content of MgO, CaO, SrO, and BaO.

[0017] The optical glass further contains the following components in weight percent: SiO2: 3 to 13%, preferably SiO2: 6 to 11%, and / or B2O3: 8 to 18%, preferably B2O3: 9 to 15%, and / or La2O3: 28 to 40%, preferably La2O3: 31 to 38%, and / or ZrO2: 2 to 10%, preferably ZrO2: 3 to 8%, and / or TiO2: 1 0-20%, preferably TiO2: 12-18%, and / or RO: 10-30%, preferably RO: 12-25%, and / or Y2O3: 0-4%, preferably Y2O3: 0-2%, and / or Gd2O3: 0-4%, preferably Gd2O3: 0-2%, and / or Yb2O3: 0-3%, preferably Yb2O3: 0-1%, and / or Nb2O5: 6-15% , preferably Nb2O5: 8-13%, and / or ZnO: 0-5%, preferably ZnO: 0-2%, and / or Rn2O: 0-5%, preferably Rn2O: 0-3%, and / or GeO2: 0-3%, preferably GeO2: 0-1%, and / or WO3: 0-3%, preferably WO3: 0-1%, and / or Ta2O5: 0-5%, preferably Ta2O5: 0 Rn2O is one or more of Li2O, Na2O, and K2O, and the fining agent is one or more of Sb2O3, SnO, SnO2, and CeO2.

[0018] The optical glass further contains the following components in terms of weight percent: BaO: 7 to 22%, preferably BaO: 10 to 20%, more preferably BaO: 11 to 17%, and / or SrO: 0 to 10%, preferably SrO: 0 to 5%, more preferably SrO: 0 to 2%, and / or CaO: 0 to 10%, preferably CaO: 0.5 to 8%, more preferably CaO: 1 to 6%, and / or MgO: 0 to 10%, preferably MgO: 0 to 5%, more preferably MgO: 0 to 2%.

[0019] Furthermore, the optical glass may contain no WO3, no Ta2O5, no Al2O3, no GeO2, no Y2O3, no Gd2O3, no SrO, no MgO, and / or no Yb2O3.

[0020] Furthermore, the refractive index n of the optical glass d is 1.90 to 1.97, preferably 1.91 to 1.96, more preferably 1.92 to 1.95, and Abbe number ν d is 24 to 32, preferably 25 to 30, and more preferably 26 to 29.

[0021] Furthermore, the thermal expansion coefficient α of the optical glass 20 / 120℃ is 95 x 10 -7 / K or less, preferably 90×10 -7 / K or less, preferably 85×10 -7 / K or less, and / or water resistance stability D W is 2 or more, preferably 1, and / or weather resistance CR is 2 or more, preferably 1, and / or transition temperature T g is 690°C or less, preferably 680°C or less, more preferably 670°C or less, and / or the density ρ is 4.80 g / cm 3 or less, preferably 4.70 g / cm 3 or less, more preferably 4.60 g / cm 3 or less, more preferably 4.50 g / cm 3 and / or the degree of foaming is class A or higher, preferably class A0 or higher, more preferably class A 00 The upper limit of the crystallization temperature is 1180°C or lower, preferably 1150°C or lower, and more preferably 1130°C or lower.

[0022] A glass preform manufactured using the optical glass described above.

[0023] An optical element manufactured using the above optical glass or the above glass preform.

[0024] An optical instrument comprising the optical glass and / or the optical element. [Effects of the Invention]

[0025] The beneficial effects of the present invention are as follows: By rationally designing the components, the optical glass obtained by the present invention has a desired refractive index and Abbe number, and at the same time, has excellent chemical stability. DETAILED DESCRIPTION OF THE INVENTION

[0026] Hereinafter, embodiments of the optical glass according to the present invention will be described in detail, but the present invention is not limited to the embodiments described below, and can be practiced by making 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 repetition of the description, and hereinafter the optical glass of the present invention may also be referred to simply as glass.

[0027] [Optical glass] The range of components of the 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. "Converted to an oxide composition" here 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%.

[0028] 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.

[0029] <Required and optional ingredients> SiO2 adjusts the optical constants, improves the chemical stability of glass, maintains a suitable viscosity for molten glass, and reduces abrasion and erosion of refractories. In the present invention, 2% or more of SiO2 is added to achieve these effects, preferably 3% or more, and more preferably 6% or more. If the SiO2 content is too high, the glass becomes more difficult to melt and the transition temperature rises. Therefore, in the present invention, the upper limit of the SiO2 content is 15%, preferably 13%, and more preferably 11%.

[0030] B2O3 is beneficial for improving the melting property and devitrification resistance of glass and lowering the glass transition temperature. To achieve these effects, the present invention adds 5% or more B2O3, preferably a B2O3 content of 8%, and more preferably a B2O3 content of 9% or more. If the B2O3 content is too high, the chemical stability of the glass, particularly its water resistance, will be impaired, and the refractive index and light transmittance of the glass will decrease. Therefore, the B2O3 content is set to 20% or less, preferably 18% or less, and more preferably 15% or less. In some embodiments of the present invention, a B2O3 content greater than the SiO2 content is beneficial for improving the weather resistance and bubble content of the glass and achieving good abrasion resistance.

[0031] La2O3 is an effective component for increasing the refractive index of glass and is significantly effective in improving the chemical stability and devitrification resistance of glass. If its content is less than 25%, it is difficult to achieve the required optical constants, while if its content exceeds 45%, the glass's tendency to devitrify increases and its thermal stability deteriorates. Therefore, the La2O3 content is 25 to 45%, preferably 28 to 40%, and more preferably 31 to 38%.

[0032] Y2O3 can increase the refractive index and devitrification resistance of the glass, but if its content exceeds 8%, the chemical stability and weather resistance of the glass will deteriorate. Therefore, in the present invention, the Y2O3 content is 0 to 8%, preferably 0 to 4%, and more preferably 0 to 2%. In some embodiments, it is even more preferable that the glass does not contain Y2O3.

[0033] Although Gd2O3 can increase the refractive index and chemical stability of the glass, if its content exceeds 8%, the devitrification resistance and abrasion resistance of the glass deteriorate. Therefore, the Gd2O3 content is 0 to 8%, preferably 0 to 4%, and more preferably 0 to 2%. In some embodiments, it is even more preferable that no Gd2O3 is contained.

[0034] Yb2O3 is also a component that imparts high refractive index and low dispersion to the glass, and if its content exceeds 5%, the crystallization resistance of the glass decreases. Therefore, the Yb2O3 content should be 0 to 5%, preferably 0 to 3%, more preferably 0 to 1%, and even more preferably no Yb2O3.

[0035] ZrO2 can increase the viscosity, hardness, refractive index, and chemical stability of optical glass and can also lower the thermal expansion coefficient of glass, but if the ZrO2 content is too high, the devitrification resistance of the glass decreases, the melting difficulty increases, the melting temperature rises, inclusions occur inside the glass, and the light transmittance decreases. Therefore, in the present invention, the ZrO2 content is 1 to 12%, preferably 2 to 10%, and more preferably 3 to 8%.

[0036] Although MgO can effectively reduce the relative partial dispersion of 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 limited to 0 to 10%, preferably 0 to 5%, and more preferably 0 to 2%. In some embodiments, it is even more preferable to not include MgO.

[0037] CaO adjusts the optical constants of the glass, increases its chemical stability, improves its processability, reduces its high-temperature viscosity and surface tension, and eases the difficulty of glass production. However, if its content is too high, the devitrification resistance of the glass decreases. Therefore, the CaO content is 0 to 10%, preferably 0.5 to 8%, and more preferably 1 to 6%.

[0038] In some embodiments, by controlling the ratio of CaO to the total content of SiO2 and ZrO2 (SiO2 + ZrO2), CaO / (SiO2 + ZrO2), within the range of 0.01 to 2.0, it is possible to optimize the abrasion resistance and weather resistance of the glass and prevent an increase in density and a decrease in hardness of the glass. Therefore, preferably, CaO / (SiO2 + ZrO2) is 0.01 to 2.0, more preferably, CaO / (SiO2 + ZrO2) is 0.02 to 1.5, even more preferably, CaO / (SiO2 + ZrO2) is 0.05 to 1.0, and even more preferably, CaO / (SiO2 + ZrO2) is 0.08 to 0.7.

[0039] Although adding SrO to glass can adjust the refractive index and Abbe number of the glass, if the SrO content is too high, the chemical stability and devitrification resistance of the glass decrease. Therefore, the SrO content is limited to 0 to 10%, preferably 0 to 5%, and more preferably 0 to 2%. In some embodiments, it is even more preferable that no SrO is contained.

[0040] BaO increases the refractive index, meltability, and thermal stability of the glass, and can improve the abrasion resistance and light transmittance of the glass, but if its content is too high, the density of the glass increases and the devitrification resistance decreases. Therefore, the BaO content is 7 to 22%, preferably 10 to 20%, and more preferably 11 to 17%.

[0041] In some embodiments, by controlling the total content RO of alkaline earth metal oxides MgO, CaO, SrO, and BaO to within 7 to 35%, the glass can easily obtain desired optical constants, the chemical stability of the glass can be optimized, and a decrease in the devitrification resistance of the glass can be prevented. Therefore, RO is preferably 7 to 35%, more preferably 10 to 30%, and even more preferably 12 to 25%.

[0042] In some embodiments, controlling the ratio (La2O3+Gd2O3+Y2O3) / RO of the total content of La2O3, Gd2O3, and Y2O3 (La2O3+Gd2O3+Y2O3) to the content of RO within the range of 0.8 to 5.0 makes it easier to obtain the desired refractive index and Abbe number of the glass, improves the chemical stability of the glass, and prevents increases in the glass transition temperature and thermal expansion coefficient. Therefore, preferably, (La2O3+Gd2O3+Y2O3) / RO is 0.8 to 5.0, more preferably, 1.0 to 4.0, even more preferably, 1.2 to 3.0, and even more preferably, 1.5 to 2.5.

[0043] ZnO adjusts the refractive index and dispersion of the glass, and can lower the high-temperature viscosity and transition temperature of the glass. If the ZnO content is too high, the devitrification resistance of the glass will deteriorate. Therefore, the ZnO content is 0 to 8%, preferably 0 to 5%, and more preferably 0 to 2%.

[0044] In some embodiments, by controlling the ratio of the ZnO content to the CaO content, ZnO / CaO, to 2.0 or less, deterioration of the weather resistance and crystallization resistance of the glass can be prevented, and excellent weather resistance and crystallization resistance can be obtained. Therefore, ZnO / CaO is preferably 2.0 or less, and more preferably 1.5 or less. Furthermore, by controlling ZnO / CaO to 1.0 or less, the bubble content of the glass can be further optimized. Therefore, ZnO / CaO is more preferably 1.0 or less, and even more preferably ZnO / CaO is 0.5 or less.

[0045] Although TiO2 can increase the refractive index and dispersion of glass and improve its resistance to devitrification, too high a content can significantly reduce the dispersion coefficient, increase the tendency to crystallize, and cause obvious coloration of the glass. Therefore, the TiO2 content is limited to 7-22%, preferably 10-20%, and more preferably 12-18%.

[0046] In some embodiments, controlling the ratio (B2O3+SrO) / (CaO+BaO+TiO2) of the total content of B2O3 and SrO (B2O3+SrO) to the total content of CaO, BaO, and TiO2 (CaO+BaO+TiO2) within a range of 0.1 to 1.0 is advantageous for improving the crystallization resistance and weather resistance of the glass. Therefore, preferably, (B2O3+SrO) / (CaO+BaO+TiO2) is 0.1 to 1.0, and more preferably, (B2O3+SrO) / (CaO+BaO+TiO2) is 0.1 to 0.8. Furthermore, controlling (B2O3+SrO) / (CaO+BaO+TiO2) within a range of 0.2 to 0.6 can further reduce the thermal expansion coefficient and density of the glass. Therefore, more preferably, (B2O3+SrO) / (CaO+BaO+TiO2) is 0.2 to 0.6, and even more preferably, (B2O3+SrO) / (CaO+BaO+TiO2) is 0.25 to 0.5.

[0047] Nb2O5 is a high-refractive, high-dispersion component that can increase the refractive index and devitrification resistance of glass and reduce the thermal expansion coefficient of glass. In order to achieve the above effects, the present invention adds 5% or more of Nb2O5, with the Nb2O5 content preferably being 6% or more, and more preferably being 8% or more. If the Nb2O5 content exceeds 20%, the thermal stability and weather resistance of the glass will decrease and the light transmittance will decrease, so the Nb2O5 content in the present invention is 20% or less, preferably 15% or less, and more preferably 13% or less.

[0048] In some embodiments, the weather resistance of the glass can be improved and the thermal expansion coefficient of the glass can be reduced by controlling the ratio (SiO2 + BaO) / (La2O3 + Nb2O5) of the total content of SiO2 and BaO (SiO2 + BaO) to the total content of La2O3 and Nb2O5 (La2O3 + Nb2O5) within 0.2 to 1.0. Therefore, the ratio (SiO2 + BaO) / (La2O3 + Nb2O5) is preferably 0.2 to 1.0, and more preferably 0.25 to 0.9. Furthermore, the bubble content and stripes of the glass can be further optimized by controlling the ratio (SiO2 + BaO) / (La2O3 + Nb2O5) within 0.3 to 0.8. Therefore, more preferably, (SiO2+BaO) / (La2O3+Nb2O5) is 0.3 to 0.8, and even more preferably, (SiO2+BaO) / (La2O3+Nb2O5) is 0.4 to 0.6.

[0049] In some embodiments, the ratio (SiO2+Nb2O5) / (B2O3+La2O3) of the total content of SiO2 and Nb2O5 (SiO2+Nb2O5) to the total content of B2O3 and La2O3 (B2O3+La2O3) is controlled within a range of 0.15 to 1.0, thereby reducing the density of the glass and optimizing the degree of cellularity of the glass. Therefore, the ratio (SiO2+Nb2O5) / (B2O3+La2O3) is preferably 0.15 to 1.0, and more preferably 0.2 to 0.8. Furthermore, by controlling (SiO2+Nb2O5) / (B2O3+La2O3) to within the range of 0.25 to 0.65, the abrasion resistance and crystallization resistance of the glass can be further optimized. Therefore, it is more preferable that (SiO2+Nb2O5) / (B2O3+La2O3) be 0.25 to 0.65, and even more preferably that (SiO2+Nb2O5) / (B2O3+La2O3) be 0.3 to 0.5.

[0050] In some embodiments, by controlling the ratio of the RO content to the Nb2O5 content, RO / Nb2O5, within a range of 0.5 to 5.0, the glass transition temperature can be lowered and the chemical stability of the glass can be improved. Therefore, RO / Nb2O5 is preferably 0.5 to 5.0, and more preferably 0.6 to 3.0. Furthermore, by controlling RO / Nb2O5 within a range of 0.8 to 2.5, the thermal expansion coefficient of the glass can be further reduced and the bubble content of the glass can be optimized. Therefore, RO / Nb2O5 is more preferably 0.8 to 2.5, and even more preferably 1.0 to 2.0.

[0051] Ta2O5 can increase the refractive index and improve the devitrification resistance of glass, but if its content is too high, the thermal stability of the glass decreases, the density increases, and it becomes difficult to control the optical constants within the desired range. On the other hand, Ta2O5 is very expensive compared to other components, and from the viewpoint of practicality and cost, it is necessary to reduce its use amount as much as possible. Therefore, the Ta2O5 content in the present invention is limited to 0 to 8%, preferably 0 to 5%, and more preferably 0 to 1%. In some embodiments, it is even more preferable that Ta2O5 is not included.

[0052] In some embodiments, the chemical stability and crystallization resistance of the glass can be improved by controlling the ratio of the total content of Gd2O3, Y2O3, and Ta2O5 (Gd2O3 + Y2O3 + Ta2O5) to the content of TiO2 (Gd2O3 + Y2O3 + Ta2O5) / TiO2 to 1.0 or less. Therefore, preferably, (Gd2O3 + Y2O3 + Ta2O5) / TiO2 is 1.0 or less, and more preferably, (Gd2O3 + Y2O3 + Ta2O5) / TiO2 is 0.8 or less. Furthermore, by controlling (Gd2O3 + Y2O3 + Ta2O5) / TiO2 to 0.5 or less, the porosity of the glass can be further optimized and the glass transition temperature can be lowered. Therefore, more preferably, (Gd2O3+Y2O3+Ta2O5) / TiO2 is 0.5 or less, and even more preferably, (Gd2O3+Y2O3+Ta2O5) / TiO2 is 0.2 or less.

[0053] The alkaline metal oxide 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, but a high RnO content reduces the devitrification resistance and chemical stability of the glass. Therefore, in the present invention, the RnO content is 0 to 8%, preferably 0 to 5%, and more preferably 0 to 3%.

[0054] Although WO3 can increase the refractive index and mechanical strength of glass, a WO3 content exceeding 5% reduces the thermal stability and devitrification resistance of the glass. Therefore, the upper limit of the WO3 content is 5%, preferably 3%, and more preferably 1%. In some embodiments, it is even more preferable to exclude WO3.

[0055] 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 3%, and more preferably 0 to 1%. In some embodiments, it is even more preferable that Al2O3 is not contained.

[0056] Although GeO2 can increase the refractive index and devitrification resistance, if its content is too high, the chemical stability of the glass decreases. Furthermore, GeO2 is very expensive compared to other components, and from the viewpoint of practicality and cost, its use amount must be reduced as much as possible. Therefore, the GeO2 content in the present invention is limited to 0 to 5%, preferably 0 to 3%, more preferably 0 to 1%, and even more preferably, GeO2 is not included.

[0057] In the present invention, the addition of 0 to 1% of one or more of Sb2O3, SnO, SnO2, and CeO2 as a fining agent can enhance the fining effect of the glass and improve the cellularity of the glass. Preferably, the fining agent content is 0 to 0.5%, and more preferably 0 to 0.2%. Because the types and contents of the components of the optical glass of the present invention are rationally designed and the glass has an excellent cellularity, in some embodiments, it is preferable to not include 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 platinum or platinum alloy containers used for melting the glass and deterioration of molding dies. Therefore, the Sb2O3 content in the present invention is preferably 0 to 1%, more preferably 0 to 0.5%, even more preferably 0 to 0.2%, and even more preferably no Sb2O3. SnO and SnO2 can also be used as fining agents, but if their content exceeds 1%, the glass tends to become more colored, and when the glass is heated, softened, and reshaped by press molding, Sn acts as a starting point for crystal nucleation, causing 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 0.2%, and even more preferably does not contain SnO2. The SnO content is preferably 0 to 1%, more preferably 0 to 0.5%, even more preferably 0 to 0.2%, and even more preferably does not contain SnO. The function and content ratio of CeO2 are identical to those of SnO2, and its content is preferably 0 to 1%, more preferably 0 to 0.5%, even more preferably 0 to 0.2%, and even more preferably does not contain CeO2.

[0058] <Ingredients that should not be included> 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.

[0059] 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.

[0060] In consideration of the environment, the optical glass of the present invention preferably does not contain As2O3 and PbO.

[0061] 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 patent of the present invention.

[0062] The properties of the optical glass of the present invention will be described below.

[0063] <Refractive index and Abbe number> The refractive index of optical glass (n d ) and Abbe number (ν d ) is tested according to the method specified in GB / T 7962.1-2010.

[0064] In some embodiments, the refractive index (n d ) has a lower limit of 1.90, preferably 1.91, and more preferably 1.92.

[0065] In some embodiments, the refractive index (n d ) has an upper limit of 1.97, preferably 1.96, and more preferably 1.95.

[0066] In some embodiments, the Abbe number (ν d ) has a lower limit of 24, preferably a lower limit of 25, and more preferably a lower limit of 26.

[0067] In some embodiments, the Abbe number (ν d ) has an upper limit of 32, preferably 30, and more preferably 29.

[0068] <Thermal expansion coefficient> The thermal expansion coefficient of optical glass (α 20 / 120℃ ) is measured at 20 to 120°C according to the method specified in GB / T 7962.16-2010.

[0069] In some embodiments, the thermal expansion coefficient (α 20 / 120℃ ) is 95 x 10 -7 / K or less, preferably 90×10 -7 / K or less, preferably 85×10 -7 / K or less.

[0070] <Water resistance stability> Water resistance stability of optical glass (D W ) (powder method) is tested according to the method specified in GB / T 17129.

[0071] In some embodiments, the water resistance stability (D W ) is class 2 or more, preferably class 1.

[0072] <Weather resistance> The weather resistance (CR) test method for optical glass is as follows: the sample is placed in a test box in a saturated water vapor environment with a relative humidity of 90%, and the temperature is alternately circulated at 40-50°C every hour for 15 cycles. The weather resistance classification is determined based on the amount of turbidity change before and after leaving the sample, and the weather resistance classification is shown in Table 1.

[0073] [Table 1]

[0074] In some embodiments, the weather resistance (CR) of the optical glass of the present invention is Class 2 or higher, preferably Class 1.

[0075] <Bubble content> The bubble content of optical glass is tested according to the method specified in GB / T 7962.8-2010.

[0076] In some embodiments, the bubble content of the optical glass of the present invention is Class A or higher, preferably Class A0 or higher, more preferably Class A 00 It is a grade.

[0077] <density> The density (ρ) of optical glass is tested according to the method described in GB / T 7962.20-2010.

[0078] In some embodiments, the density (ρ) of the optical glass of the present invention is 4.80 g / cm 3 or less, preferably 4.70 g / cm 3 or less, more preferably 4.60 g / cm 3 or less, more preferably 4.50 g / cm 3 The following is the result.

[0079] <Transition temperature> Optical glass transition temperature (T g ) is measured according to the method specified in GB / T 7962.16-2010.

[0080] In some embodiments, the transition temperature (T g ) is 690°C or less, preferably 680°C or less, and more preferably 670°C or less.

[0081] <Crystal upper limit temperature> The temperature gradient furnace method is used to measure the crystallization resistance of optical glass. A 180 x 10 x 10 mm glass sample is prepared, the sides are polished, and the sample is placed in a furnace with a temperature gradient (10°C / cm) at a maximum temperature of 1200°C for four hours. The sample is then removed and allowed to cool naturally to room temperature. The crystallization state of the glass is observed under a microscope, and the maximum temperature at which crystallization is confirmed is taken as the maximum crystallization temperature of the glass. The lower the maximum crystallization temperature of the glass, the better the crystallization resistance of the glass.

[0082] In some embodiments, the upper crystallization temperature limit of the optical glass of the present invention is 1180° C. or lower, preferably 1150° C. or lower, and more preferably 1130° C. or lower.

[0083] [Optical glass manufacturing method] The optical glass of the present invention is manufactured by the following method: after mixing conventional raw materials, including but not limited to oxides, hydroxides, complex salts (carbonates, nitrates, sulfates, etc.), boric acid, etc., using conventional processes, the resulting furnace material is placed in a melting furnace (platinum or platinum alloy crucible) at 1200°C to 1500°C and melted. The resulting mixture is then clarified 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, manufacturing methods, and process parameters according to their actual needs.

[0084] [Glass preforms and optical elements] Glass preforms can be manufactured using optical glass produced using press molding methods such as direct drop molding, polishing, or hot press molding. That is, a precision glass preform can be produced by directly precision drop molding molten optical glass, or by mechanical processing such as grinding or polishing, or by using optical glass to produce a preform blank for press molding, and then hot press processing and polishing this preform blank to produce a glass preform. It should be noted that the means for manufacturing optical preforms are not limited to the above means.

[0085] 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 blank from the optical glass of the present invention and use this blank to carry out hot press molding, precision press molding, or the like to produce optical elements such as lenses and prisms.

[0086] The optical preform and optical element of the present invention are both formed from the optical glass of the present invention. The optical 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.

[0087] 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.

[0088] [Optical equipment] Optical elements formed from the 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.

[0089] Example <Examples of optical glass> To further clearly illustrate the technical solutions of the present invention, the following non-limiting examples are provided.

[0090] In this example, optical glasses having the components shown in Tables 2-1 to 4-2 were obtained using the above-described optical glass manufacturing method. The properties of each glass were measured using the test methods described in the present invention, and the results are shown in Tables 2-1 to 4-2.

[0091] [Table 2]

[0092] [Table 3]

[0093] [Table 4]

[0094] [Table 5]

[0095] [Table 6]

[0096] [Table 7]

[0097] <Example of glass preform> The glasses obtained in Examples 1 to 24 of the optical glass are used to produce preforms for 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, using 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 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.

[0099] 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.

[0100] <Example of optical equipment> 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. An optical glass comprising, in weight percent: SiO 2 : 2-15%, B 2 O 3 : 5-20%, La 2 O 3 : 25-45%, ZrO 2 : 1-12%, TiO 2 : 7-22%, Nb 2 O 5 :5~20%, RO:7~35%, CaO / (SiO 2 +ZrO 2 ) is 0.01 to 2.0, RO / Nb 2 O 5 is 0.5 to 2.0, and the refractive index n d is 1.90 to 1.95, Abbe number ν d is 24 to 29, and the RO is the total content of MgO, CaO, SrO, and BaO.

2. 10. The optical glass of claim 1 further comprising the following components in weight percent: Y 2 O 3 : 0-8%, and / or Gd 2 O 3 : 0 to 8%, and / or Yb 2 O 3 : 0 to 5%, and / or ZnO: 0 to 8%, and / or Rn 2 O: 0-8% and / or GeO 2 : 0-5%, and / or WO 3 : 0 to 5%, and / or Ta 2 O 5 : 0 to 8%, and / or Al 2 O 3 : 0 to 5%, and / or fining agent: 0 to 1%, the above Rn 2 O is Li 2 O, Na 2 OK 2 The fining agent is one or more of Sb 2 O 3 , SnO, SnO 2 , CeO 2 It is one or more of the following.

3. An optical glass comprising, in weight percent: SiO 2 : 2-15%, B 2 O 3 : 5-20%, La 2 O 3 : 25-45%, ZrO 2 : 1-12%, TiO 2 : 7-22%, Nb 2 O 5 : 5-20%, RO: 7-35%, Y 2 O 3 : 0-8%, Gd 2 O 3 : 0-8%, Yb 2 O 3 : 0-5%, ZnO: 0-8%, Rn 2 O: 0-8%, GeO 2 : 0-5%, WO 3 : 0 to 5%, Ta 2 O 5 : 0-8%, Al 2 O 3 : 0-5%, Clarifying agent: 0-1%, CaO / (SiO 2 +ZrO 2 ) is 0.01 to 2.0, RO / Nb 2 O 5 is 0.5 to 2.0, and the refractive index n d is 1.90 to 1.95, Abbe number ν d is 24 to 29, the RO is the total content of MgO, CaO, SrO, and BaO, and the Rn 2 O is Li 2 O, Na 2 OK 2 The fining agent is one or more of Sb 2 O 3 , SnO, SnO 2 , CeO 2 It is one or more of the following.

4. 10. The optical glass of claim 1, comprising the components in weight percent and satisfying one or more of the following nine conditions: 1) CaO / (SiO 2 +ZrO 2 ) is 0.02 to 2.0; 2) (B 2 THE 3 +SrO) / (CaO+BaO+TiO 2 )は0.1~1.0; 3) (Gd 2 O 3 +Y 2 O 3 +Ta 2 O 5 ) / TiO 2 is less than or equal to 1.0; 4) (SiO) 2 +BaO) / (La 2 SHE 3 +Nb 2 SHE 5 )は0.2~1.0; 5) B 2 O 3 The content of SiO 2 content is greater than that of 6) (SiO) 2 +Nb 2 SHE 5 ) / (B 2 SHE 3 +La 2 SHE 3 )は0.15~1.0; 7) ZnO / CaO is 2.0 or less; 8) (La 2 O 3 +Gd 2 O 3 +Y 2 O 3 ) / RO is 0.8 to 5.

0.

5. 10. The optical glass of claim 1, comprising the components in weight percent and satisfying one or more of the following eight conditions: 1) CaO / (SiO 2 +ZrO 2 ) is 0.02 to 1.5; 2) (B 2 THE 3 +SrO) / (CaO+BaO+TiO 2 )は0.1~0.8; 3) (Gd 2 O 3 +Y 2 O 3 +Ta 2 O 5 ) / TiO 2 is less than or equal to 0.8; 4) (SiO) 2 +BaO) / (La 2 SHE 3 +Nb 2 SHE 5 )は0.25~0.9; 5) (SiO) 2 +Nb 2 SHE 5 ) / (B 2 SHE 3 +La 2 SHE 3 )は0.2~0.8; 6) ZnO / CaO is 1.5 or less; 7) RO / Nb 2 O 5 is 0.6-2.0; 8) (La 2 O 3 +Gd 2 O 3 +Y 2 O 3 ) / RO is 1.0 to 4.

0.

6. 10. The optical glass of claim 1, comprising the components in weight percent and satisfying one or more of the following eight conditions: 1) CaO / (SiO 2 +ZrO 2 ) is 0.05 to 1.0; 2) (B 2 THE 3 +SrO) / (CaO+BaO+TiO 2 )は0.2~0.6; 3) (Gd 2 O 3 +Y 2 O 3 +Ta 2 O 5 ) / TiO 2 is less than or equal to 0.5; 4) (SiO) 2 +BaO) / (La 2 SHE 3 +Nb 2 SHE 5 )は0.3~0.8; 5) (SiO) 2 +Nb 2 SHE 5 ) / (B 2 SHE 3 +La 2 SHE 3 )は0.25~0.65; 6) ZnO / CaO is 1.0 or less; 7) RO / Nb 2 O 5 is 0.8-2.0; 8) (La 2 O 3 +Gd 2 O 3 +Y 2 O 3 ) / RO is 1.2 to 3.

0.

7. 10. The optical glass of claim 1, comprising the components in weight percent and satisfying one or more of the following eight conditions: 1) CaO / (SiO 2 +ZrO 2 ) is 0.08 to 0.7; 2) (B 2 THE 3 +SrO) / (CaO+BaO+TiO 2 )は0.25~0.5; 3) (Gd 2 O 3 +Y 2 O 3 +Ta 2 O 5 ) / TiO 2 is less than or equal to 0.2; 4) (SiO) 2 +BaO) / (La 2 SHE 3 +Nb 2 SHE 5 )は0.4~0.6; 5) (SiO) 2 +Nb 2 SHE 5 ) / (B 2 SHE 3 +La 2 SHE 3 )は0.3~0.5; 6) ZnO / CaO is 0.5 or less; 7) RO / Nb 2 O 5 is 1.0 to 2.0; 8) (La 2 O 3 +Gd 2 O 3 +Y 2 O 3 ) / RO is 1.5 to 2.

5.

8. 10. The optical glass of claim 1, comprising the following components in weight percent: SiO 2 : 3 to 13%, and / or B 2 O 3 : 8-18%, and / or La 2 O 3 : 28-40% and / or ZrO 2 : 2 to 10%, and / or TiO 2 : 10-20%, and / or RO: 10-30%, and / or Y 2 O 3 : 0-4%, and / or Gd 2 O 3 : 0 to 4%, and / or Yb 2 O 3 : 0 to 3%, and / or Nb 2 O 5 : 6 to 15%, and / or ZnO: 0 to 5%, and / or Rn 2 O: 0-5% and / or GeO 2 : 0-3%, and / or WO 3 : 0 to 3%, and / or Ta 2 O 5 : 0 to 5%, and / or Al 2 O 3 : 0 to 3%, and / or fining agent: 0 to 0.5%, the RO is the total content of MgO, CaO, SrO, and BaO, and the Rn 2 O is Li 2 O, Na 2 OK 2 The fining agent is one or more of Sb 2 O 3 , SnO, SnO 2 , CeO 2 It is one or more of the following.

9. 10. The optical glass of claim 1, comprising the following components in weight percent: SiO 2 : 6-11%, and / or B 2 O 3 : 9-15%, and / or La 2 O 3 : 31-38%, and / or ZrO 2 : 3 to 8%, and / or TiO 2 : 12-18%, and / or RO: 12-25%, and / or Y 2 O 3 : 0-2% and / or Gd 2 O 3 : 0 to 2%, and / or Yb 2 O 3 : 0 to 1%, and / or Nb 2 O 5 : 8 to 13%, and / or ZnO: 0 to 2%, and / or Rn 2 O: 0-3% and / or GeO 2 : 0-1%, and / or WO 3 : 0 to 1%, and / or Ta 2 O 5 : 0 to 1%, and / or Al 2 O 3 : 0 to 1%, and / or fining agent: 0 to 0.2%, the RO is the total content of MgO, CaO, SrO, and BaO, and the Rn 2 O is Li 2 O, Na 2 OK 2 The fining agent is one or more of Sb 2 O 3 , SnO, SnO 2 , CeO 2 It is one or more of the following.

10. 10. The optical glass of claim 1, comprising the following components in weight percent: BaO: 7 to 22%, and / or SrO: 0 to 10%, and / or CaO: 0 to 10%, and / or MgO: 0 to 10%.

11. 10. The optical glass of claim 1, comprising the following components in weight percent: BaO: 11 to 17%, and / or SrO: 0 to 2%, and / or CaO: 1 to 6%, and / or MgO: 0 to 2%.

12. The component is WO 3 does not contain and / or Ta 2 O 5 does not contain and / or Al 2 O 3 and / or GeO 2 does not contain and / or Y 2 O 3 Does not contain and / or Gd 2 O 3 does not contain SrO, and / or does not contain MgO, and / or does not contain Yb 2 O 3 The optical glass of claim 1, which does not contain

13. The refractive index n of the optical glass d is 1.91 to 1.95, Abbe number ν d 2. The optical glass according to claim 1, wherein

14. The refractive index n of the optical glass d is 1.92 to 1.95, Abbe number ν d 2. The optical glass according to claim 1, wherein

15. The thermal expansion coefficient α of the optical glass 20 / 120℃ is 95 x 10 -7 / K or less, and / or water resistance stability D W is Class 2 or higher, and / or weather resistance CR is Class 2 or higher, and / or transition temperature T g is 690°C or less, and / or density ρ is 4.80g / cm 3 2. The optical glass according to claim 1, wherein the glass has a porosity of Class A or higher and / or an upper crystallization temperature of 1,180°C or lower.

16. The thermal expansion coefficient α of the optical glass 20 / 120℃ is 85 x 10 -7 / K or less, and / or water resistance stability D W is Class 1, and / or weather resistance CR is Class 1, and / or transition temperature T g is 670°C or less, and / or density ρ is 4.60 g / cm 3 or less, and / or the foaming degree is A 00 2. The optical glass according to claim 1, which has a crystallization temperature of 1130°C or lower and / or a maximum crystallization temperature of 1130°C or lower.

17. A glass preform manufactured using the optical glass according to any one of claims 1 to 16.

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

19. An optical instrument comprising the optical glass according to any one of claims 1 to 16.

Images