Optical glass, optical elements, and optical instruments

Abstract

Through rational component design, we provide optical glass with a relatively low coefficient of thermal expansion. [Solution] Provide an optical glass containing the following components by weight: SiO2: 17-32%, B2O3: 18-32%, BaO: 12-27.5%, SrO: 2-15%, Ln2O3: 7.5-28%, Al2O3: greater than 0% and less than or equal to 10%, (La2O3+SrO) / BaO is 0.5-2.5, and the Ln2O3 is the total content of La2O3, Gd2O3, Y2O3, and Yb2O3.

Description

Technical Field

[0001] The present invention relates to optical glass, and particularly to optical glass having a relatively low coefficient of thermal expansion, and a glass preform, an optical element, and an optical device manufactured therefrom.

Background Art

[0002] In recent years, with the popularization of smartphones, surveillance security devices, in-vehicle imaging, etc., optical elements made of optical glass are widely applied to these devices, and the demand for optical glass with a refractive index of 1.59 to 1.66 and an Abbe number of 55 to 61 is also increasing. Optical elements mounted on in-vehicle devices and equipment, and optical elements mounted on optical devices that generate heat such as projectors, copiers, laser printers, etc. are used in an environment with large temperature changes. When the coefficient of thermal expansion of the optical glass is too large, thermal expansion of the optical element occurs due to changes in the environmental temperature. Since the coefficient of expansion of the optical element fixing fixture is different, stress is generated in the optical element, and further birefringence occurs, which may cause changes in imaging characteristics. Patent Document 1 (CN115991571A) discloses optical glass with a refractive index of 1.59 to 1.65 and an Abbe number of 54 to 70, but its coefficient of thermal expansion is relatively high, so it cannot meet the usage requirements in high-performance optical devices.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The technical problem to be solved by the present invention is to provide optical glass having a relatively low coefficient of thermal expansion.

Means for Solving the Problems

[0005] The technical solution employed by this invention to solve the technical problems is as follows:

[0006] (1) Optical glass containing the following components by weight %,: SiO2: 17-32%; B2O3: 18-32%; BaO: 12-27.5%; SrO: 2-15%; Ln2O3: 7.5-28%; Al2O3: greater than 0% and less than or equal to 10%, (La2O3+SrO) / BaO is 0.5-2.5, and the Ln2O3 is the total content of La2O3, Gd2O3, Y2O3, and Yb2O3.

[0007] (2) The optical glass described in (1), further comprising the following components by weight %,: ZrO2: 0-10%, and / or Nb2O5: 0-5%, and / or WO3: 0-5%, and / or ZnO: 0-4.5%, and / or Rn2O: 0-6.5%, and / or MgO: 0-5%, and / or CaO: 0-4%, and / or TiO2: 0-5%, and / or Ta2O5: 0-5%, and / or P2O5: 0-4%, and / or F: 0-5%, and / or clarifying agent: 0-1%, wherein Rn2O is one or more of Li2O, Na2O, and K2O, and the clarifying agent is one or more of Sb2O3, SnO2, SnO, and CeO2.

[0008] (3) An optical glass comprising SiO2, B2O3, BaO and SrO, with the components expressed in weight percent, containing 7.5 to 28% Ln2O3, (La2O3 + SrO) / BaO being 0.5 to 2.5, and the refractive index of the optical glass n d ν is 1.59-1.66, Abbe number ν d The coefficient of thermal expansion is α, which is 55-61. 20 / 300℃ is 90 x 10 -7 Below / K, the Ln2O3 is the total content of La2O3, Gd2O3, Y2O3, and Yb2O3.

[0009] (4) Optical glass as described in (3), containing the following components by weight %,: SiO2: 17-32%, and / or B2O3: 18-32%, and / or BaO: 12-27.5%, and / or SrO: 2-15%, and / or Al2O3: greater than 0% and 10%, and / or ZrO2: 0-10%, and / or Nb2O5: 0-5%, and / or WO3: 0-5%, and / or ZnO: 0-4.5%, and / or Rn2O: 0-6.5%, and / Alternatively, the composition may be MgO: 0-5%, and / or CaO: 0-4%, and / or TiO2: 0-5%, and / or Ta2O5: 0-5%, and / or P2O5: 0-4%, and / or F: 0-5%, and / or clarifying agent: 0-1%, where Rn2O is one or more of Li2O, Na2O, and K2O, and the clarifying agent is one or more of Sb2O3, SnO2, SnO, and CeO2.

[0010] (5) An optical glass according to any of (1) to (4), whose composition is expressed in weight percent and which can satisfy one or more of the following 10 conditions. 1) The B2O3 / SiO2 ratio is 0.7 to 1.7, preferably 0.75 to 1.5, more preferably 0.8 to 1.3, and even more preferably 0.85 to 1.1. 2) The (La2O3+SrO) / BaO ratio is 0.7 to 2.0, preferably 0.8 to 1.8, and more preferably 0.9 to 1.5. 3) The SrO / La2O3 ratio is 0.1 to 1.5, preferably 0.2 to 1.2, more preferably 0.3 to 1.0, and even more preferably 0.35 to 0.8. 4) The La2O3 / SiO2 ratio is 0.3 to 1.2, preferably 0.35 to 1.0, more preferably 0.4 to 0.9, and even more preferably 0.45 to 0.8. 5) The ratio of (BaO+SrO) / (ZrO2+Al2O3) is 1.0 to 15.0, preferably 1.5 to 10.0, more preferably 2.0 to 8.0, and even more preferably 2.5 to 5.0. 6) The Al2O3 / B2O3 ratio is 0.01 to 0.45, preferably 0.05 to 0.4, and more preferably 0.1 to 0.3. 7) The ZrO2 / SiO2 ratio is 0.01 to 0.4, preferably 0.05 to 0.35, and more preferably 0.1 to 0.3. 8) The Al2O3 / ZrO2 ratio is 0.2 to 8.0, preferably 0.5 to 6.0, more preferably 0.8 to 4.0, and even more preferably 1.0 to 2.0. 9) The ratio of (Y2O3+Gd2O3+ZnO+CaO+Rn2O) / SrO is 1.0 or less, preferably 0.8 or less, more preferably 0.5 or less, and even more preferably 0.3 or less. 10) (ZnO+CaO+Rn2O) / La2O3 is 1.0 or less, preferably (ZnO+CaO+Rn2O) / La2O3 is 0.8 or less, more preferably (ZnO+CaO+Rn2O) / La2O3 is 0.5 or less, and even more preferably (ZnO+CaO+Rn2O) / La2O3 is 0.3 or less, and the Rn2O is one or more of Li2O, Na2O, and K2O.

[0011] (6) Optical glass according to any one of (1) to (4), comprising the following components by weight %: SiO2: 21-30%, preferably SiO2: 22-28%, and / or B2O3: 21-30%, preferably B2O3: 22-29%, and / or Ln2O3: 10-25%, preferably Ln2O3: 11-20%, and / or BaO: 15-25%, preferably BaO: 16-23%, and / or SrO: 3-13%, preferably SrO: 5.5-11%, and / or A l2O3:1~8%, preferably Al2O3:2~7%, and / or ZrO2:0.5~8%, preferably ZrO2:1~7%, and / or Nb2O5:0~3%, preferably Nb2O5:0~1%, more preferably no Nb2O5, and / or WO3:0~3%, preferably WO3:0~1%, more preferably no WO3, and / or ZnO:0~3%, preferably ZnO:0~2%, more preferably no ZnO, and / or Rn2O:0~5% Preferably Rn2O: 0-2%, and / or MgO: 0-3%, preferably MgO: 0-2%, more preferably no MgO, and / or CaO: 0-3%, preferably CaO: 0-2%, more preferably no CaO, and / or TiO2: 0-3%, preferably TiO2: 0-2%, more preferably no TiO2, and / or Ta2O5: 0-3%, preferably Ta2O5: 0-1%, more preferably no Ta2O5, and / or P2O5: The composition is 0-2%, preferably P2O5:0-1%, more preferably no P2O5, and / or F:0-3%, preferably F:0-2%, more preferably no F, and / or clarifying agent:0-0.5%, preferably clarifying agent:0-0.2%, where Ln2O3 is the total content of La2O3, Gd2O3, Y2O3, and Yb2O3, Rn2O is one or more of Li2O, Na2O, and K2O, and the clarifying agent is one or more of Sb2O3, SnO2, SnO, and CeO2.

[0012] (7) Optical glass according to any one of (1) to (4), comprising the following components by weight %,: La2O3: 7.5 to 23%, preferably La2O3: 11 to 20%, more preferably La2O3: 12 to 18%, and / or Gd2O3: 0 to 8%, preferably Gd2O3: 0 to 5%, more preferably Gd2O3: 0 to 1.5%, even more preferably Gd2O3-free, and / or Y2O3: 0 to 8%, preferably Y2O3: 0 to 5%, more preferably Y2O3: 0 to 1.5%, even more preferably Y2O3-free, and / or Yb2O3 The content of the following components is 0-5%, preferably Yb2O3:0-3%, more preferably Yb2O3:0-2%, even more preferably no Yb2O3, and / or Li2O:0-5%, preferably Li2O:0-3%, more preferably Li2O:0-2%, and / or Na2O:0-5%, preferably Na2O:0-3%, more preferably Na2O:0-2%, even more preferably no Na2O, and / or K2O:0-5%, preferably K2O:0-3%, more preferably K2O:0-2%, even more preferably no K2O.

[0013] (8) Refractive index n d The Abbe number ν is 1.59 to 1.66, preferably 1.60 to 1.65, more preferably 1.61 to 1.64. d The optical glass according to any one of (1) to (4), wherein the ratio is 55 to 61, preferably 56 to 60, and more preferably 57 to 59.

[0014] (9) Average light transmittance τ of optical glass with a thickness of 12 mm or less at 400-800 nm 400~800nm The optical glass has a light transmittance of 99.0% or more, preferably 99.5% or more, more preferably 99.7% or more, and / or a thickness of 12 mm or less, at 400 nm. 400nm The optical glass according to any one of claims (1) to (4), wherein the content is 99.0% or more, preferably 99.5% or more, and more preferably 99.7% or more.

[0015] (10) The thickness of the optical glass is 1 to 12 mm, preferably 2 to 12 mm, more preferably 5 to 10 mm, and even more preferably 2 mm or 5 mm or 8 mm or 10 mm, the optical glass according to (9).

[0016] (11) The transition temperature T of the optical glass g is 650 °C or less, preferably 600 to 650 °C, more preferably 605 to 645 °C, even more preferably 610 to 640 °C, and / or the hydrolysis resistance D W is Class 3 or higher, preferably Class 2 or higher, more preferably Class 1, and / or the density ρ is 3.60 g / cm 3 or less, preferably 3.50 g / cm 3 or less, more preferably 3.40 g / cm 3 or less, and / or the Knoop hardness H K is 500×10 7 Pa or higher, preferably 515×10 7 Pa or higher, more preferably 530×10 7 Pa or higher, and / or the Young's modulus E is 7000×10 7 Pa or higher, preferably 7300×10 7 Pa or higher, more preferably 7600×10 7 Pa or higher, and / or the abrasion degree F A is 200 or less, preferably 175 or less, more preferably 150 or less, and / or the thermal expansion coefficient α 20 / 300℃ is 90×10 -7 / K or less, preferably 50×10 -7 / K to 85×10 -7 / K, more preferably 55×10 -7 / K to 80×10 -7 / K, even more preferably 60×10 -7 / K to 72×10 -7 / K, and / or the high temperature viscosity at 1200 °C is 60 dPaS or less, preferably 40 dPaS or less, more preferably 30 dPaS or less, and / or the crystallization resistance is Class B or higher, preferably Class A, the optical glass according to any one of (1) to (4).

[0017] (12) A glass preform manufactured from any one of the optical glass described in (1) to (11).

[0018] (13) An optical element manufactured from one of the optical glass described in (1) to (11) or the glass preform described in (12).

[0019] (14) An optical instrument comprising an optical glass as described in one of (1) to (11), or an optical element as described in (13). [Effects of the Invention]

[0020] The beneficial effects of the present invention are as follows: Due to its rational composition design, the thermal expansion coefficient of the optical glass of the present invention is relatively low. [Modes for carrying out the invention]

[0021] The embodiments of the optical glass according to the present invention will be described in detail below, but the present invention is not limited to the embodiments described below and can be appropriately modified and implemented within the scope of the object of the present invention. Furthermore, although omissions may be made as appropriate, the gist of the present invention is not limited by repetition of the description. Hereinafter, the optical glass of the present invention may be simply referred to as glass.

[0022] (Optical glass) The component ranges of the optical glass of the present invention will be described below. In this specification, unless otherwise specified, the content of each component, the total content, and the gross content are expressed as the weight percentage of the oxide component relative to the total glass material. Here, "converted to oxide composition" means that the total weight of oxide substances when the oxides, complex salts, hydroxides, etc. used as raw materials for the composition of the optical glass of the present invention decompose into oxides during melting is taken as 100%.

[0023] Specifically, the numerical ranges described herein include upper and lower limits, and “greater than or equal to” and “less than or equal to” include endpoint values, as well as all integers and fractions included in the range, and are not limited to the specific values ​​described where the range is limited. The terms “and / or” used herein are inclusive; for example, “A and / or B” means A only, B only, or both A and B.

[0024] <Essential and Optional Ingredients> SiO2 forms the backbone of optical glass and, as a glass network component, plays a role in maintaining the chemical stability of the glass and improving its resistance to devitrification. When the SiO2 content is less than 17%, the above effects are not significant. Therefore, the lower limit of the SiO2 content is 17%, preferably 21%, and more preferably 22%. When the SiO2 content exceeds 32%, the meltability of the glass decreases, the transition temperature and high-temperature viscosity increase, which is unfavorable for improving the light transmittance of the glass. Therefore, the upper limit of the SiO2 content is 32%, preferably 30%, and more preferably 28%.

[0025] B2O3 is a component that forms the network structure of glass and is an essential component of the glass of the present invention. Adding 18% or more of B2O3 can improve the meltability, devitrification resistance, and light transmittance of the glass. However, if the B2O3 content exceeds 32%, the chemical stability of the glass deteriorates, glass volatilization increases, which is unfavorable for stable control of optical constants, and stripes tend to worsen. Therefore, the B2O3 content is 18-32%, preferably 21-30%, and more preferably 22-29%.

[0026] In some embodiments, controlling the ratio of B2O3 content to SiO2 content, B2O3 / SiO2, within the range of 0.7 to 1.7 can reduce the high-temperature viscosity of the glass while simultaneously preventing a decrease in Young's modulus. Therefore, preferably B2O3 / SiO2 is 0.7 to 1.7, and more preferably B2O3 / SiO2 is 0.75 to 1.5. Furthermore, controlling B2O3 / SiO2 to within 0.8 to 1.3 can further optimize the light transmittance and thermal expansion coefficient of the glass. Therefore, even more preferably B2O3 / SiO2 is 0.8 to 1.3, and even more preferably B2O3 / SiO2 is 0.85 to 1.1.

[0027] La2O3 is an essential component of the glass of this invention, and it can increase the refractive index of the glass, enhance the chemical stability and mechanical strength of the glass, and reduce the relative partial dispersion of the glass. In this invention, the above effects are achieved by adding 7.5% or more of La2O3, preferably 11% or more, more preferably 12% or more, and when the La2O3 content exceeds 23%, the crystallinity resistance and thermal stability of the glass tend to deteriorate. Therefore, in this invention, the La2O3 content is 23% or less, preferably 20% or less, and more preferably 18% or less.

[0028] In some embodiments, controlling the ratio of La2O3 content to SiO2 content, La2O3 / SiO2, within the range of 0.3 to 1.2 allows the glass to have excellent abrasion resistance while simultaneously preventing an increase in the transition temperature. Therefore, preferably, La2O3 / SiO2 is 0.3 to 1.2, and more preferably, La2O3 / SiO2 is 0.35 to 1.0. Furthermore, the light transmittance of the glass can be further optimized by controlling La2O3 / SiO2 to within 0.4 to 0.9. Therefore, more preferably, La2O3 / SiO2 is 0.4 to 0.9, and even more preferably, La2O3 / SiO2 is 0.45 to 0.8.

[0029] Gd2O3 can enhance the refractive index and chemical stability of glass, but if its content exceeds 8%, the glass's devitrification resistance and abrasion resistance deteriorate. Therefore, the Gd2O3 content is 0-8%, preferably 0-5%, and more preferably 0-1.5%. In some embodiments, it is even more preferable to have no Gd2O3 at all.

[0030] Y2O3 can increase the refractive index of glass and lower its density and the upper limit temperature for crystal precipitation, but if its content exceeds 8%, the devitrification resistance and weather resistance of the glass deteriorate. Therefore, the Y2O3 content in the present invention is 0 to 8%, preferably 0 to 5%, and more preferably 0 to 1.5%. In some embodiments, it is even more preferable to have no Y2O3 at all.

[0031] Yb2O3 is a component that imparts high refractive index and low dispersibility to glass, but if its content exceeds 5%, the crystallinity resistance of the glass deteriorates. Therefore, the Yb2O3 content is 0-5%, preferably 0-3%, and more preferably 0-2%. In some embodiments, it is even more preferable to not include Yb2O3 at all.

[0032] In some embodiments, by controlling the total content of Ln2O3 (La2O3, Gd2O3, Y2O3, Yb2O3) to within the range of 7.5-28%, the expected refractive index can be achieved, chemical stability can be enhanced, and a decrease in the crystallinity of the glass can be prevented. Therefore, the Ln2O3 content is preferably 7.5-28%, more preferably 10-25%, and even more preferably 11-20%.

[0033] ZrO2 can adjust the optical constants of glass and improve its resistance to devitrification and chemical stability. However, if its content exceeds 10%, the melting performance of the glass decreases, the melting temperature rises, inclusions appear inside the glass, its transmittance decreases, and it becomes difficult to maintain a low transition temperature. Therefore, the ZrO2 content is 0-10%, preferably 0.5-8%, and more preferably 1-7%.

[0034] In some embodiments, controlling the ratio of ZrO2 content to SiO2 content, ZrO2 / SiO2, within the range of 0.01 to 0.4 can enhance the hardness and chemical stability of the glass and prevent a decrease in crystallinity. Therefore, preferably, ZrO2 / SiO2 is 0.01 to 0.4, more preferably 0.05 to 0.35, and even more preferably 0.1 to 0.3.

[0035] Nb2O5 can increase the refractive index and dispersion of glass, and improve its crystallinity and chemical stability. However, if its content exceeds 5%, the dispersion of the glass increases, making it impossible to achieve the optical properties of the glass of the present invention, and the light transmittance of the glass also decreases. Therefore, the Nb2O5 content is 0-5%, preferably 0-3%, and more preferably 0-1%. In some embodiments, it is even more preferable to not include Nb2O5 at all.

[0036] While WO3 can increase the refractive index and dispersion of glass, if its content is too high, the light transmittance of the glass decreases and its crystallinity deteriorates. Therefore, the WO3 content is 0-5%, preferably 0-3%, and more preferably 0-1%. In some embodiments, it is even more preferable to have no WO3 at all.

[0037] ZnO can lower the transition temperature of glass, increase its chemical stability, and reduce its high-temperature viscosity. However, if the ZnO content is too high, the glass's crystal resistance deteriorates and its coefficient of thermal expansion increases. Therefore, the ZnO content in this invention is 0-4.5%, preferably 0-3%, and more preferably 0-2%. In some embodiments, it is even more preferable to have no ZnO at all.

[0038] Alkaline metal oxides Rn2O (Rn2O being one or more of Li2O, Na2O, and K2O) can lower the transition temperature of glass, adjust the optical constants and high-temperature viscosity of glass, and improve the meltability of glass. However, if the content is high, the devitrification resistance and chemical stability of glass will decrease. Therefore, the Rn2O content in the present invention is 0 to 6.5%, preferably 0 to 5%, and more preferably 0 to 2%.

[0039] While Li2O can lower the transition temperature of glass, high levels of Li2O are detrimental to the acid resistance and thermal expansion coefficient of the glass, and it is corrosive to molten vessels (e.g., platinum crucibles). Therefore, the Li2O content is 0-5%, preferably 0-3%, and more preferably 0-2%.

[0040] Na2O can improve the meltability of glass and lower the glass transition temperature, but if its content is too high, the chemical stability and weather resistance of the glass will decrease. Therefore, the Na2O content is 0-5%, preferably 0-3%, and more preferably 0-2%. In some embodiments, it is even more preferable to have no Na2O at all.

[0041] K2O can improve the thermal stability and meltability of glass, but if the K2O content exceeds 5%, the devitrification resistance of the glass decreases. Therefore, the K2O content is 0-5%, preferably 0-3%, and more preferably 0-2%. In some embodiments, it is even more preferable to have no K2O at all.

[0042] While MgO can lower the melting temperature and relative partial dispersion of glass, excessively high MgO content reduces the glass's crystallinity and stability. Therefore, the MgO content is 0-5%, preferably 0-3%, and more preferably 0-2%. In some embodiments, it is even more preferable to have no MgO at all.

[0043] CaO helps improve the density and workability of glass, but if the CaO content is too high, it becomes difficult for the optical constants of the glass to meet the design requirements and the crystallinity deteriorates. Therefore, the CaO content is 0-4%, preferably 0-3%, and more preferably 0-2%. In some embodiments, it is even more preferable to have no CaO at all.

[0044] In some embodiments, controlling the ratio of the total content of ZnO, CaO, and Rn2O (ZnO+CaO+Rn2O) to the content of La2O3 ((ZnO+CaO+Rn2O) / La2O3) to 1.0 or less can improve the chemical stability and light transmittance of the glass and prevent deterioration of density and abrasion. Therefore, preferably (ZnO+CaO+Rn2O) / La2O3 is 1.0 or less, more preferably (ZnO+CaO+Rn2O) / La2O3 is 0.8 or less, even more preferably (ZnO+CaO+Rn2O) / La2O3 is 0.5 or less, and even more preferably (ZnO+CaO+Rn2O) / La2O3 is 0.3 or less.

[0045] SrO can improve the devitrification resistance of glass and enhance its melting performance, but if its content is too high, it becomes difficult for the refractive index of the glass to meet the design requirements, and the cost of the glass also increases rapidly. Therefore, the SrO content is 2-15%, preferably 3-13%, and more preferably 5.5-11%.

[0046] In some embodiments, controlling the ratio of SrO content to La2O3 content, SrO / La2O3, within the range of 0.1 to 1.5 can improve the chemical stability and Young's modulus of the glass and prevent an increase in the thermal expansion coefficient of the glass. Therefore, preferably, SrO / La2O3 is 0.1 to 1.5, more preferably 0.2 to 1.2, even more preferably 0.3 to 1.0, and even more preferably 0.35 to 0.8.

[0047] In some embodiments, by controlling the ratio of the total content of Y2O3, Gd2O3, ZnO, CaO, and Rn2O (Y2O3+Gd2O3+ZnO+CaO+Rn2O) to the content of SrO ((Y2O3+Gd2O3+ZnO+CaO+Rn2O) / SrO) to 1.0 or less, it is possible to lower the high-temperature viscosity and transition temperature of the glass while simultaneously preventing deterioration of hardness. Therefore, preferably (Y2O3+Gd2O3+ZnO+CaO+Rn2O) / SrO is 1.0 or less, more preferably (Y2O3+Gd2O3+ZnO+CaO+Rn2O) / SrO is 0.8 or less, even more preferably (Y2O3+Gd2O3+ZnO+CaO+Rn2O) / SrO is 0.5 or less, and even more preferably (Y2O3+Gd2O3+ZnO+CaO+Rn2O) / SrO is 0.3 or less.

[0048] In this invention, BaO can adjust the refractive index of the glass, improve its transmittance and devitrification resistance, and lower the refractive index temperature coefficient and thermal expansion coefficient of the glass. However, if the BaO content is too high, the chemical stability of the glass will decrease. Therefore, the BaO content is 12-27.5%, preferably 15-25%, and more preferably 16-23%.

[0049] In some embodiments, by controlling the ratio of the total content of La2O3 and SrO (La2O3+SrO) to the content of BaO ((La2O3+SrO) / BaO) to within the range of 0.5 to 2.5, the thermal expansion coefficient and transition temperature of the glass can be reduced, and a decrease in the Young's modulus of the glass can be prevented. Therefore, preferably (La2O3+SrO) / BaO is 0.5 to 2.5, more preferably (La2O3+SrO) / BaO is 0.7 to 2.0, even more preferably (La2O3+SrO) / BaO is 0.8 to 1.8, and even more preferably (La2O3+SrO) / BaO is 0.9 to 1.5.

[0050] TiO2 can increase the refractive index of glass and be used to form a glass network. Adding it in appropriate amounts can make the glass more stable, but if the content is too high, the light transmittance of the glass decreases and the glass becomes noticeably discolored. Therefore, the TiO2 content in this invention is 0-5%, preferably 0-3%, and more preferably 0-2%. In some embodiments, it is even more preferable to not include TiO2.

[0051] Al2O3 can improve the stability and devitrification resistance of glass and increase its strength, but if its content exceeds 10%, the chemical stability and meltability of the glass decrease. Therefore, in this invention, the Al2O3 content is greater than 0 and less than or equal to 10%, preferably 1 to 8%, and more preferably 2 to 7%.

[0052] In some embodiments, controlling the ratio of Al2O3 content to ZrO2 content, Al2O3 / ZrO2, within the range of 0.2 to 8.0 can reduce the high-temperature viscosity of the glass and prevent a decrease in the crystallinity resistance of the glass. Therefore, preferably Al2O3 / ZrO2 is 0.2 to 8.0, and more preferably Al2O3 / ZrO2 is 0.5 to 6.0. Furthermore, controlling Al2O3 / ZrO2 within 0.8 to 4.0 can further optimize the hardness and abrasion resistance of the glass. Therefore, even more preferably Al2O3 / ZrO2 is 0.8 to 4.0, and even more preferably Al2O3 / ZrO2 is 1.0 to 2.0.

[0053] In some embodiments, controlling the ratio of Al2O3 content to B2O3 content, Al2O3 / B2O3, within the range of 0.01 to 0.45 can reduce the thermal expansion coefficient of the glass while simultaneously preventing an increase in the transition temperature of the glass and increasing the light transmittance of the glass. Therefore, preferably, Al2O3 / B2O3 is 0.01 to 0.45, more preferably 0.05 to 0.4, and even more preferably 0.1 to 0.3.

[0054] In some embodiments, the ratio (BaO+SrO) / (ZrO2+Al2O3) of the total content of BaO and SrO to the total content of ZrO2 and Al2O3 can be controlled within the range of 1.0 to 15.0, thereby reducing the density of the glass while simultaneously optimizing the degree of glass abrasion. Therefore, preferably (BaO+SrO) / (ZrO2+Al2O3) is 1.0 to 15.0, and more preferably (BaO+SrO) / (ZrO2+Al2O3) is 1.5 to 10.0. Furthermore, the high-temperature viscosity of the glass can be further optimized by controlling (BaO+SrO) / (ZrO2+Al2O3) within the range of 2.0 to 8.0. Therefore, it is more preferable that (BaO+SrO) / (ZrO2+Al2O3) is between 2.0 and 8.0, and even more preferable that (BaO+SrO) / (ZrO2+Al2O3) is between 2.5 and 5.0.

[0055] Ta2O5 can increase the refractive index of glass and improve its resistance to devitrification, but if its content is too high, the thermal stability of the glass decreases and its density increases. Furthermore, Ta2O5 is very expensive compared to other components, and from the viewpoint of practicality and cost, it is necessary to reduce the amount used as much as possible. Therefore, the content of Ta2O5 in this invention is limited to 0-5%, preferably 0-3%, and more preferably 0-1%. In some embodiments, it is even more preferable to not include Ta2O5 at all.

[0056] P2O5 can improve the devitrification resistance of glass, but if its content is too high, the chemical stability of the glass deteriorates. Therefore, the P2O5 content is 0-4%, preferably 0-2%, and more preferably 0-1%. In some embodiments, it is even more preferable to have no P2O5 at all.

[0057] The present invention enhances the clarifying effect of glass and improves the degree of bubbles in glass by adding 0 to 1% of one or more types of clarifying agents such as Sb2O3, SnO2, SnO, and CeO2, preferably with a clarifying agent content of 0 to 0.5%, and more preferably with a clarifying agent content of 0 to 0.2%.

[0058] F can be used to adjust the refractive index of glass and lower the refractive index temperature coefficient, but it volatilizes during the production process, causing an environmental burden. Furthermore, volatilization from the glass surface within the molding temperature range can form heterogeneous areas, which may reduce the consistency between the glass quality and optical constants. Therefore, the F content is 0-5%, preferably 0-3%, and more preferably 0-2%. In some embodiments, it is even more preferable to have no F at all.

[0059] <Ingredients that should not be included> In the glass of the present invention, even if oxides of transition metals such as V, Cr, Mn, Fe, Co, Ni, Cu, Ag, and Mo are included in small amounts, either individually or in combination, the glass becomes colored, certain wavelengths in the visible light region are absorbed, and the visible light transmission effect of the present invention is weakened. Therefore, it is preferable that optical glass that particularly requires wavelength transmittance in the visible light region does not actually contain such oxides.

[0060] In recent years, there has been a trend to control the use of oxides of Th, Cd, Tl, Os, Be, and Se as hazardous chemical substances, and environmental protection efforts are necessary not only in the glass manufacturing process but also in the processing process and the treatment of the finished product. Therefore, when considering the impact on the environment, it is preferable to exclude these substances except for unavoidable inclusions. As a result, the optical glass does not actually contain substances that pollute the environment. Accordingly, the optical glass of the present invention can be manufactured, processed, and disposed of without taking special environmental measures.

[0061] To be environmentally conscious, the optical glass of the present invention preferably does not contain As2O3 and PbO. Although As2O3 has the effect of removing air bubbles and preventing discoloration of the glass, the addition of As2O3 increases platinum erosion in the glass melting furnace, especially the platinum melting furnace, allowing more platinum ions to enter the glass and adversely affecting the service life of the platinum melting furnace.

[0062] The terms “not added,” “not contained,” and “0%” as used herein mean that this component was not intentionally added as a raw material for the glass of the present invention. However, small or trace amounts of impurities or components that were not intentionally added as raw materials and / or equipment for manufacturing the glass may be present in the final glass, and these are also covered by the patent of the present invention.

[0063] The properties of the optical glass of the present invention will be described below.

[0064] <Refractive index and Abbe number> Refractive index of optical glass (n d ) and Abbe number (ν d ) has been tested according to the method specified in GB / T 7962.1-2010.

[0065] In some embodiments, the refractive index (n) of the optical glass of the present invention d The upper limit of ) is 1.66, preferably 1.65, and more preferably 1.64.

[0066] In some embodiments, the refractive index (n) of the optical glass of the present invention is determined by the present invention. d The lower limit of ) is 1.59, preferably 1.60, and more preferably 1.61.

[0067] In some embodiments, the Abbe number (ν) of the optical glass of the present invention d The upper limit of ) is 61, preferably 60, and more preferably 59.

[0068] In some embodiments, the Abbe number (ν) of the optical glass of the present invention d The lower limit of ) is 55, preferably 56, and more preferably 57.

[0069] <Transition Temperature> Transition temperature of optical glass (T g ) is measured according to the method specified in GB / T7962.16-2010. In some embodiments, the transition temperature (T) of the optical glass of the present invention is specified. g The temperature is 650°C or lower, preferably 600-650°C, more preferably 605-645°C, and even more preferably 610-640°C.

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

[0071] In some embodiments, the water resistance stability of the optical glass of the present invention (D W ) is of class 3 or more, preferably class 2 or more, more preferably class 1.

[0072] <density> The density (ρ) of optical glass is tested according to the method specified in GB / T7962.20-2010. In some embodiments, the density (ρ) of the optical glass of the present invention is 3.60 g / cm³. 3 Preferably, 3.50 g / cm³ 3 More preferably, 3.40 g / cm³ 3 The following applies:

[0073] <Knoop hardness> Knoop hardness (H) of optical glass K ) has been tested according to the test method specified in GB / T7962.18-2010.

[0074] In some embodiments, the Knoop hardness (H) of the optical glass of the present invention is determined by the Knoop hardness (H) of the optical glass of the present invention. K ) is 500 x 10 7 Pa or higher, preferably 515 × 10 7 Pa or higher, comfortable 530×10 7 It is Pa or higher.

[0075] Young's modulus The Young's modulus (E) of optical glass is calculated by measuring the longitudinal and transverse wave velocities using ultrasound and following the formula below.

number

number

[0076] In some embodiments, the Young's modulus (E) of the optical glass of the present invention is 7000 × 10⁻¹⁰. 7 Pa or higher, preferably 7300 × 10 7 Pa or higher, futuristic 7600 x 10 7 It is Pa or higher.

[0077] <Abrasion level> Abrasion degree of optical glass (F A This value is obtained by multiplying the ratio of the wear amount of the sample to the wear amount (volume) of the standard sample (H-K9 glass) by 100 under exactly the same conditions, and the formula is as follows:

number

[0078] In some embodiments, the degree of wear (F) of the optical glass of the present invention is A ) is 200 or less, preferably 175 or less, more preferably 150 or less.

[0079] <Coefficient of thermal expansion> The thermal expansion coefficient of optical glass (α20 / 300℃ The data shown is from measurements taken at 20-300°C according to the method specified in GB / T7962.16-2010.

[0080] In some embodiments, the thermal expansion coefficient of the optical glass of the present invention (α 20 / 300℃ ) is 90 x 10 -7 / K or less, preferably 50 × 10 -7 / K~85×10 -7 / K, more comfortable 55×10 -7 / K~80×10 -7 / K, more preferably 60×10 -7 / K~72×10 -7 It is / K.

[0081] <Crystallization resistance> The test method for the crystallinity resistance of optical glass is as follows: Cut the glass sample to 20 × 20 × 10 mm and heat to temperature T g The glass sample is placed in a muffle furnace at +200°C and kept warm for 60 minutes. After removal and cooling, the presence or absence of devitrification or crystal grain formation on the glass surface and inside is observed. If there is no devitrification or crystal grain in the glass sample, it is judged that the glass has excellent crystal resistance.

[0082] According to the above test method, glass with no devitrification or crystalline particles on the surface and no crystalline particles inside is designated as "A", glass with no crystalline particles inside but with devitrification or crystalline particles on the surface is designated as "B", glass with 1 to 10 crystalline particles inside is designated as "C", glass with 10 to 20 crystalline particles inside is designated as "D", and glass with 20 or more densely packed crystalline particles inside is designated as "×".

[0083] In some embodiments, the crystallinity resistance of the optical glass of the present invention is B-grade or higher, preferably A-grade.

[0084] <High temperature viscosity> The high-temperature viscosity of optical glass is tested according to the following method: it is tested using the rotational method with a THETA Rheotronic II high-temperature viscometer, and the numerical unit is dPaS (poise), with a smaller value indicating lower viscosity.

[0085] In some embodiments, the high-temperature viscosity of the optical glass of the present invention at 1200°C is 60 dPaS or less, preferably 40 dPaS or less, and more preferably 30 dPaS or less.

[0086] <400~800nm ​​average light transmittance> Average light transmittance of optical glass at 400-800nm ​​(τ 400~800nm The glass is tested according to the method specified in GB / T 7962.12-2010. The higher the average light transmittance in the 400-800nm ​​range, the lower the average loss of light transmission in the optical glass.

[0087] In some embodiments, the average light transmittance (τ) of optical glass with a thickness of 12 mm or less at 400-800 nm is determined. 400~800nm The percentage is 99.0% or higher, preferably 99.5% or higher, and more preferably 99.7% or higher.

[0088] The thickness of the optical glass is preferably 1 to 12 mm, more preferably 2 to 12 mm, even more preferably 5 to 10 mm, and even more preferably 2 mm, 5 mm, 8 mm, or 10 mm.

[0089] <400nm light transmittance> 400nm light transmittance of optical glass (τ 400nm The glass is tested according to the method specified in GB / T 7962.12-2010. The higher the 400nm light transmittance, the lower the blue light absorption of the optical glass, and the more the illumination effect tends to approach white light.

[0090] In some embodiments, the 400nm light transmittance (τ) of optical glass with a thickness of 12 mm or less is 400nm The percentage is 99.0% or higher, preferably 99.5% or higher, and more preferably 99.7% or higher.

[0091] The thickness of the optical glass is preferably 1 to 12 mm, more preferably 2 to 12 mm, even more preferably 5 to 10 mm, and even more preferably 2 mm, 5 mm, 8 mm, or 10 mm.

[0092] (Manufacturing method) The method for manufacturing the optical glass of the present invention is as follows: The glass of the present invention is manufactured using conventional raw materials and processes, including but not limited to oxides, hydroxides, fluorides, various salts (carbonates, nitrates, sulfates, phosphates, metaphosphates), boric acid, etc. After compounding by conventional methods, the prepared furnace material is placed in a melting furnace (such as a crucible of platinum, gold, or platinum alloy) at 1000 to 1400°C and melted. Subsequently, it is clarified and homogenized to obtain a homogeneous molten glass free from bubbles and undissolved material. This molten glass is then placed in a mold for casting and annealed. Those skilled in the art can appropriately select the raw materials, manufacturing method, and process parameters as needed.

[0093] (Glass preforms and optical elements) Glass preforms can be manufactured from optical glass using press forming methods such as polishing, hot press forming, and precision press forming. Specifically, optical preforms can be manufactured from optical glass by mechanical processing such as grinding and polishing, or by manufacturing a press forming blank from optical glass, then hot press forming this blank and polishing it to produce an optical preform, or by precision press forming a polished blank to produce an optical preform.

[0094] It should be noted that the means for manufacturing the optical preform are not limited to those described above. 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 manufacture optical elements such as lenses and prisms by performing hot press molding, precision press molding, etc.

[0095] Both the optical preform and the optical element of the present invention are 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 various optical elements such as lenses and prisms with high optical value.

[0096] Examples of lenses include various types of lenses with spherical or aspherical lens surfaces, such as concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, and plano-concave lenses.

[0097] The optical glass of the present invention can be used to stretch optical elements such as optical fibers.

[0098] (optical equipment) Optical elements formed from the optical glass of the present invention can be used to manufacture optical devices such as photographic devices, imaging devices, endoscopes, display devices, and monitoring devices.

[0099] Examples <Examples of optical glass applications> To further clarify the technical solutions of the present invention, the following non-limiting embodiments are provided.

[0100] This embodiment uses the optical glass manufacturing method described above to obtain optical glass having the compositions shown in Tables 1 to 3. Furthermore, the properties of each glass were measured using the test method described in the present invention, and the results are shown in Tables 1 to 3. In the following embodiment, the average light transmittance (τ) of the optical glass at 400-800 nm is... 400~800nm ) and 400nm light transmittance (τ 400nm The results shown are for a test of 10mm thick optical glass. [Table 1] [Table 2] [Table 3]

[0101] <Examples of glass preforms> The glass obtained in Examples 1 to 24 of the optical glass is used to manufacture various lenses and preforms such as prisms, including concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, and plano-concave lenses, using polishing or press forming methods such as reheat press forming or precision press forming.

[0102] <Examples of optical elements> The preform obtained in the above example of optical preform is tempered, and the refractive index is finely adjusted while reducing internal strain in the glass so that the optical properties such as the refractive index reach the desired value.

[0103] Next, each preform is ground and polished to produce various lenses and prisms, such as concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, and plano-concave lenses. An anti-reflective coating can also be applied to the surface of the resulting optical elements.

[0104] <Examples of optical equipment> The optical elements manufactured in the above-described embodiment can be used in imaging devices, sensors, microscopes, pharmaceutical technology, digital projection, communications, optical communications technology / information transmission, optics / illumination in the automotive field, photolithography technology, excimer lasers, wafers, computer chips and integrated circuits and electronic devices including such circuits and chips, or imaging equipment and devices in the automotive field, by forming optical components or optical parts using one or more optical elements through optical design.

Claims

1. An optical glass containing the following components in weight %: SiO 2 : 17 to 32%; B 2 O 3 : 18 to 32%; BaO: 12 to 27.5%; SrO: 2 to 15%; Ln 2 O 3 : 7.5 to 28%; Al 2 O 3 : more than 0 and 10% or less, (La 2 O 3 + SrO) / BaO is 0.5 to 2.5, and the above-mentioned Ln 2 O 3 is the total content of La 2 O 3 , Gd 2 O 3 , Y 2 O 3 , Yb 2 O 3 .

2. The optical glass according to claim 1, further comprising the following components by weight: ZrO 2 : 0-10%, and / or Nb 2 O 5 : 0-5%, and / or WO 3 : 0-5%, and / or ZnO: 0-4.5%, and / or Rn 2 O: 0–6.5%, and / or MgO: 0–5%, and / or CaO: 0–4%, and / or TiO 2 : 0-5%, and / or Ta 2 O 5 : 0-5%, and / or P 2 O 5 : 0-4%, and / or F: 0-5%, and / or clarifying agent: 0-1%, the Rn 2 O is Li 2 O, Na 2 OK 2 It is one or more types of O, and the clarifying agent is Sb 2 O 3 SnO 2 SnO, CeO 2 It is one or more species of [something].

3. Optical glass, SiO 2 B 2 O 3 It contains BaO and SrO, and its composition is expressed in weight percent, with 7.5-28% Ln 2 O 3 (La 2 O 3 The ratio of (+SrO) / BaO is 0.5 to 2.5, and the refractive index n of the optical glass is n d 1.59–1.66, Abbe number ν d The coefficient of thermal expansion is 55-61, α 20 / 300℃ is 90 x 10 -7 / K or less, the above Ln 2 O 3 is La 2 O 3 , Gd 2 O 3 , Y 2 O 3 Yb 2 O 3 This is the total content.

4. The optical glass according to claim 3, comprising the following components by weight: SiO 2 : 17-32%, and / or B 2 O 3 : 18–32%, and / or BaO: 12–27.5%, and / or SrO: 2–15%, and / or Al 2 O 3 : Greater than 0 and less than or equal to 10%, and / or ZrO 2 : 0-10%, and / or Nb 2 O 5 : 0-5%, and / or WO 3 : 0-5%, and / or ZnO: 0-4.5%, and / or Rn 2 O: 0–6.5%, and / or MgO: 0–5%, and / or CaO: 0–4%, and / or TiO 2 : 0-5%, and / or Ta 2 O 5 : 0-5%, and / or P 2 O 5 : 0-4%, and / or F: 0-5%, and / or clarifying agent: 0-1%, the Rn 2 O is Li 2 O, Na 2 OK 2 It is one or more types of O, and the clarifying agent is Sb 2 O 3 SnO 2 SnO, CeO 2 It is one or more species of [something].

5. The optical glass according to any one of claims 1 to 4, comprising the components in weight percent and satisfying one or more of the following 10 conditions: 1) B 2 O 3 / SiO 2 is 0.7 to 1.7; 2) (Let 2 O 3 +SrO) / BaOは0.7~2.0; 3) SrO / La 2 O 3 is 0.1 to 1.5; 4) La 2 O 3 / SiO 2 is 0.3 to 1.2; 5) (BaO+SrO) / (ZrO 2 +Al 2 O 3 )は1.0~15.0; 6) To 2 EITHER 3 / B 2 EITHER 3 は0.01~0.45; 7) ZrO 2 / SiO 2 is 0.01 to 0.4; 8) Al 2 O 3 / ZrO 2 is 0.2 to 8.0; 9) (Y 2 O 3 +Gd 2 O 3 +ZnO+CaO+Rn 2 O) / SrO is less than or equal to 1.0; 10) (ZnO + CaO + Rn 2 O) / La 2 O 3 The Rn is 1.0 or less. 2 O is Li 2 O, Na 2 OK 2 It is one or more types of O.

6. The optical glass according to any one of claims 1 to 4, comprising the components in weight percent and satisfying one or more of the following 10 conditions: 1) B 2 O 3 / SiO 2 is 0.75 to 1.5; 2) (Let 2 O 3 +SrO) / BaOは0.8~1.8; 3) SrO / La 2 O 3 is 0.2 to 1.2; 4) La 2 O 3 / SiO 2 is 0.35 to 1.0; 5) (BaO+SrO) / (ZrO 2 +Al 2 O 3 )は1.5~10.0; 6) To 2 EITHER 3 / B 2 EITHER 3 は0.05~0.4; 7) ZrO 2 / SiO 2 is 0.05 to 0.35; 8) Al 2 O 3 / ZrO 2 is 0.5 to 6.0; 9) (Y 2 O 3 +Gd 2 O 3 +ZnO+CaO+Rn 2 O) / SrO is 0.8 or less; 10) (ZnO + CaO + Rn 2 O) / La 2 O 3 The Rn is 0.8 or less. 2 O is Li 2 O, Na 2 OK 2 It is one or more types of O.

7. The optical glass according to any one of claims 1 to 4, comprising the components in weight percent and satisfying one or more of the following 10 conditions: 1) B 2 O 3 / SiO 2 is 0.85 to 1.1; 2) (Let 2 O 3 +SrO) / BaOは0.9~1.5; 3) SrO / La 2 O 3 is 0.35 to 0.8; 4) La 2 O 3 / SiO 2 is 0.45-0.8; 5) (BaO+SrO) / (ZrO 2 +Al 2 O 3 )は2.5~5.0; 6) To 2 EITHER 3 / B 2 EITHER 3 は0.1~0.3; 7) ZrO 2 / SiO 2 is 0.1 to 0.3; 8) Al 2 O 3 / ZrO 2 is 1.0 to 2.0; 9) (Y 2 O 3 +Gd 2 O 3 +ZnO+CaO+Rn 2 O) / SrO is 0.3 or less; 10) (ZnO + CaO + Rn 2 O) / La 2 O 3 The Rn is 0.3 or less. 2 O is Li 2 O, Na 2 OK 2 It is one or more types of O.

8. The optical glass according to any one of claims 1 to 4, comprising the following components by weight: SiO 2 : 21-30%, and / or B 2 O 3 : 21-30%, and / or Ln 2 O 3 : 10-25%, and / or BaO: 15-25%, and / or SrO: 3-13%, and / or Al 2 O 3 : 1-8%, and / or ZrO 2 : 0.5–8%, and / or Nb 2 O 5 : 0-3%, and / or WO 3 : 0-3%, and / or ZnO: 0-3%, and / or Rn 2 O: 0-5%, and / or MgO: 0-3%, and / or CaO: 0-3%, and / or TiO 2 : 0-3%, and / or Ta 2 O 5 : 0-3%, and / or P 2 O 5 : 0-2%, and / or F: 0-3%, and / or clarifying agent: 0-0.5%, Ln 2 O 3 La 2 O 3 , Gd 2 O 3 , Y 2 O 3 Yb 2 O 3 Total content, Rn 2 O is Li 2 O, Na 2 OK 2 It is one or more types of O, and the clarifying agent is Sb 2 O 3 SnO 2 SnO, CeO 2 It is one or more species of [something].

9. The optical glass according to any one of claims 1 to 4, comprising the following components by weight: SiO 2 : 22-28%, and / or B 2 O 3 : 22–29%, and / or Ln 2 O 3 : 11–20%, and / or BaO: 16–23%, and / or SrO: 5.5–11%, and / or Al 2 O 3 : 2-7%, and / or ZrO 2 : 1-7%, and / or Nb 2 O 5 : 0-1%, and / or WO 3 : 0-1%, and / or ZnO: 0-2%, and / or Rn 2 O: 0-2%, and / or MgO: 0-2%, and / or CaO: 0-2%, and / or TiO 2 : 0-2%, and / or Ta 2 O 5 : 0-1%, and / or P 2 O 5 : 0-1%, and / or F: 0-2%, and / or clarifying agent: 0-0.2%, Ln 2 O 3 La 2 O 3 , Gd 2 O 3 , Y 2 O 3 Yb 2 O 3 Total content, Rn 2 O is Li 2 O, Na 2 OK 2 It is one or more types of O, and the clarifying agent is Sb 2 O 3 SnO 2 SnO, CeO 2 It is one or more species of [something].

10. The optical glass according to any one of claims 1 to 4, comprising the following components by weight: La 2 O 3 : 7.5–23%, and / or Gd 2 O 3 : 0-8%, and / or Y 2 O 3 : 0-8%, and / or Yb 2 O 3 : 0-5%, and / or Li 2 O: 0-5%, and / or Na 2 O: 0-5%, and / or K 2 O: 0-5%

11. The optical glass according to any one of claims 1 to 4, comprising the following components by weight: La 2 O 3 : 12-18%, and / or Gd 2 O 3 : 0–1.5%, and / or Y 2 O 3 : 0–1.5%, and / or Yb 2 O 3 : 0-2%, and / or Li 2 O: 0-2%, and / or Na 2 O: 0-2%, and / or K 2 O: 0-2%

12. The optical glass according to any one of claims 1 to 4: Its components include Nb 2 O 5 Does not include and / or WO 3 It does not contain, and / or does not contain ZnO, and / or does not contain MgO, and / or does not contain CaO, and / or TiO 2 Does not include and / or Ta 2 O 5 Does not include and / or P 2 O 5 Does not include F, and / or does not include Gd 2 O 3 Does not include and / or Y 2 O 3 Does not include and / or Yb 2 O 3 Does not contain, and / or Na 2 Does not contain O, and / or K 2 It does not contain O.

13. The refractive index n of the optical glass d is 1.60 to 1.65, and / or Abbe number ν d The average light transmittance τ of optical glass with a thickness of 1 to 12 mm and a range of 56 to 60 and / or 400 to 800 nm. 400～800nm This refers to a light transmittance of 99.0% or more, and / or 400nm light transmittance τ of optical glass with a thickness of 1 to 12 mm. 400nm is 99.0% or higher, and / or transition temperature T g It is rated for temperatures below 650℃ and / or water resistance stability D. W It is classified as Class 3 or higher, and / or its density ρ is 3.60 g / cm³. 3 The following and / or Knoop hardness H K is 500 x 10 7 Pa or higher, and / or Young's modulus E is 7000 × 10⁻⁶ 7 Pa or higher, and / or abrasion degree F A is 200 or less, and / or the coefficient of thermal expansion α 20 / 300℃ is 50 x 10 -7 / K~85×10 -7 The optical glass according to any one of claims 1 to 4, wherein the viscosity at / K and / or high temperature at 1200°C is 60 dPaS or less, and / or the crystallinity resistance is of grade B or higher.

14. The refractive index n of the optical glass d is 1.61 to 1.64, and / or Abbe number ν d The average light transmittance τ of optical glass with a thickness of 1 to 12 mm and a range of 57 to 59 and / or 400 to 800 nm. 400～800nm This refers to a light transmittance of 99.7% or more, and / or 400nm light transmittance τ of optical glass with a thickness of 1 to 12 mm. 400nm is 99.7% or higher, and / or transition temperature T g It is suitable for temperatures of 610-640°C and / or has a water resistance stability of D. W It is classified as Class 1, and / or its density ρ is 3.40 g / cm³. 3 The following and / or Knoop hardness H K is 530×10 7 Pa or higher, and / or Young's modulus E is 7600 × 10⁻⁶ 7 Pa or higher, and / or abrasion degree F A is 150 or less, and / or the coefficient of thermal expansion α 20 / 300℃ is 60×10 -7 / K~72×10 -7 The optical glass according to any one of claims 1 to 4, wherein the viscosity at / K and / or high temperature at 1200°C is 30 dPaS or less, and / or the crystallinity resistance is of class A.

15. An optical element manufactured from the optical glass described in any one of claims 1 to 4.

16. An optical instrument comprising the optical glass described in any one of claims 1 to 4.

17. An optical device comprising the optical element described in claim 15.

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