Optical glass and optical element

Abstract

To provide an optical glass with high light transmittance.SOLUTION: The optical glass comprises, in percentage by weight, SiO2: 30% to 50%, Nb2O5: 25% to 38%, ZrO2: 1% to 10%, BaO: 3% to 15%, SrO: 3% to 13%, and Rn2O: 5% to 20%, wherein (Na2O+BaO) / (Li2O+SrO) is 0.4 to 5.0, and the Rn2O is the total content of Li2O, Na2O and K2O. Through reasonable component design, the optical glass of the present invention has high light transmittance and low relative partial dispersion, and meets the application of a high-performance optical system.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to optical glass, and more particularly to optical glass having high light transmittance. [Background technology]

[0002] With the continuous development and progress of technology, there is an increasing demand for imaging quality and resolution in fields such as smartphones, in-vehicle cameras, and surveillance security. In order to improve imaging quality, in optical design, it is desired that optical glass has the ability to properly eliminate or reduce as much as possible the residual chromatic aberration of secondary spectrum, which requires the optical glass to have low relative partial dispersion and high light transmittance.

[0003] Chinese Patent CN102442775A discloses an optical glass with a refractive index of 1.63 to 1.72 and an Abbe number of 29 to 40. The optical glass has high relative partial dispersion and contains 30 to 60 wt% PbO, which does not meet environmental protection requirements. JP2018-168011 discloses an optical glass with a refractive index of 1.67 to 1.77 and an Abbe number of 26 to 33. The optical glass has low light transmittance, which is unfavorable for achieving high imaging quality in optical systems. Summary of the Invention [Problem to be solved by the invention]

[0004] The problem to be solved by the present invention is to provide an optical glass having high light transmittance. [Means for solving the problem]

[0005] The means by which the present invention solves the problems are as follows.

[0006] (1) An optical glass having a composition expressed in weight percentage of SiO2: 30% to 50%, Nb2O5: 25% to 38%, ZrO2: 1% to 10%, BaO: 3% to 15%, SrO: 3% to 13%, and Rn2O: 5% to 20%, in which (Na2O+BaO) / (Li2O+SrO) is 0.4 to 5.0, and the Rn2O is the total content of Li2O, Na2O, and K2O.

[0007] (2) The optical glass described in (1) contains, when expressed as a weight percentage, 0-4% B2O3, and / or 0-3% Al2O3, and / or 0-3% TiO2, and / or 0-4% Ln2O3, and / or 0-5% ZnO, and / or 0-5% CaO, and / or 0-5% MgO, and / or 0-3% P2O5, and / or 0-1% of a fining agent, wherein the Ln2O3 is one or more of La2O3, Gd2O3, Y2O3, and Yb2O3, and the fining agent is one or more of Sb2O3, SnO, SnO2, and CeO2.

[0008] (3) An optical glass, the composition of which contains SiO2, Nb2O5, ZrO2, BaO, SrO, and Rn2O, and the composition expressed as a weight percentage contains 5% to 20% Rn2O, (Na2O+BaO) / (Li2O+SrO) is 0.4 to 5.0, the Rn2O is the total content of Li2O, Na2O, and K2O, and the optical glass has a refractive index n d is 1.685 to 1.76, and the Abbe number ν d is 31.50 to 37.50, and the 400nm internal transmittance τ 400nm is 88.0% or more.

[0009] (4) The optical glass described in (3) has a composition, expressed in weight percentage, of SiO2: 30% to 50%, and / or Nb2O5: 25% to 38%, and / or ZrO2: 1% to 10%, and / or BaO: 3% to 15%, and / or SrO: 3% to 13%, and / or B2O3: 0 to 4%, and / or Al2O3: 0 to 3%, and / or TiO2: 0 to 3%, and / or Ln2O Ln2O3 is one or more of La2O3, Gd2O3, Y2O3, and Yb2O3, and the fining agent is one or more of Sb2O3, SnO, SnO2, and CeO2.

[0010] (5) The optical glass according to any one of (1) to (4) has a composition expressed in weight percentage: 1) When SiO2 / Nb2O5 is 0.9 to 1.8, preferably SiO2 / Nb2O5 is 1.0 to 1.6, and more preferably SiO2 / Nb2O5 is 1.1 to 1.5, 2) (Na2O+BaO) / (Li2O+SrO) is 0.5 to 3.5, preferably (Na2O+BaO) / (Li2O+SrO) is 0.7 to 2.5, and more preferably (Na2O+BaO) / (Li2O+SrO) is 0.9 to 2.0, 3) (TiO2+B2O3+ZnO) / SrO is 1.3 or less, preferably (TiO2+B2O3+ZnO) / SrO is 1.0 or less, more preferably (TiO2+B2O3+ZnO) / SrO is 0.01 to 0.7, and even more preferably (TiO2+B2O3+ZnO) / SrO is 0.05 to 0.4, 4) (B2O3 + Ln2O3) / (MgO + SrO + CaO) is 1.5 or less, preferably (B2O3 + Ln2O3) / (MgO + SrO + CaO) is 1.0 or less, more preferably (B2O3 + Ln2O3) / (MgO + SrO + CaO) is 0.5 or less, and even more preferably (B2O3 + Ln2O3) / (MgO + SrO + CaO) is 0.3 or less; 5) When (Nb2O5 + B2O3 + ZnO) / (MgO + SrO + CaO + BaO) is 0.9 to 5.5, preferably (Nb2O5 + B2O3 + ZnO) / (MgO + SrO + CaO + BaO) is 1.0 to 5.0, more preferably (Nb2O5 + B2O3 + ZnO) / (MgO + SrO + CaO + BaO) is 1.2 to 4.0, and even more preferably (Nb2O5 + B2O3 + ZnO) / (MgO + SrO + CaO + BaO) is 1.5 to 3.0, 6) When ZnO / ZrO2 is 1.0 or less, preferably ZnO / ZrO2 is greater than 0 and 0.8 or less, more preferably ZnO / ZrO2 is 0.01 to 0.6, and even more preferably ZnO / ZrO2 is 0.05 to 0.5, 7) When (MgO+SrO+CaO+BaO) / (Nb2O5+TiO2) is 0.2 to 1.2, preferably (MgO+SrO+CaO+BaO) / (Nb2O5+TiO2) is 0.25 to 1.0, more preferably (MgO+SrO+CaO+BaO) / (Nb2O5+TiO2) is 0.3 to 0.8, and even more preferably (MgO+SrO+CaO+BaO) / (Nb2O5+TiO2) is 0.3 to 0.6, 8) When Li2O / (Na2O+K2O) is 0.1 to 2.0, preferably Li2O / (Na2O+K2O) is 0.2 to 1.5, more preferably Li2O / (Na2O+K2O) is 0.2 to 1.0, and even more preferably Li2O / (Na2O+K2O) is 0.3 to 0.7, 9) One or more of the following nine conditions is satisfied: RnO / SrO is 0.5 to 4.5, preferably RnO / SrO is 0.6 to 4.0, more preferably RnO / SrO is 0.8 to 3.0, and even more preferably RnO / SrO is 1.0 to 2.5; The Rn2O is the total content of Li2O, Na2O, and K2O, and the Ln2O3 is one or more of La2O3, Gd2O3, Y2O3, and Yb2O3.

[0011] (6) The optical glass according to any one of (1) to (4) has a composition, expressed in weight percentage, of SiO2: 35% to 45%, preferably SiO2: 37% to 43%, and / or Nb2O5: 26% to 36%, preferably Nb2O5: 28% to 32%, and / or ZrO2: 3% to 8%, preferably ZrO2: 4% to 7%, and / or BaO: 4% to 11%. , preferably BaO: 5% to 9%, and / or SrO: 4% to 10%, preferably SrO: 5% to 8%, and / or Rn2O: 6% to 18%, preferably Rn2O: 7% to 15%, and / or B2O3: 0 to 2%, preferably B2O3: 0 to 1%, and / or Al2O3: 0 to 2%, preferably Al2O3: 0 to 1%, and / or TiO2: 0 to 2%, preferably or TiO2: 0-1%, and / or Ln2O3: 0-2%, preferably Ln2O3: 0-1%, and / or ZnO: more than 0 and 3% or less, preferably ZnO: 0.1%-2%, and / or CaO: 0-3%, preferably CaO: 0-1%, and / or MgO: 0-3%, preferably MgO: 0-1%, and / or P2O5: 0-2%, preferably P2O5: 0 to 1%, and / or fining agent: 0 to 0.5%, preferably fining agent: 0 to 0.1%, the Rn2O is the total content of Li2O, Na2O, and K2O, the Ln2O3 is one or more of La2O3, Gd2O3, Y2O3, and Yb2O3, and the fining agent is one or more of Sb2O3, SnO, SnO2, and CeO2.

[0012] (7) The optical glass according to any one of (1) to (4) has a composition, expressed in weight percentage, of Li2O: 1% to 7%, preferably Li2O: 1% to 5%, more preferably Li2O: 1% to 4%, and / or Na2O: 2% to 9%, preferably Na2O: 2% to 7%, more preferably Na2O: 2% to 6%, and / or K2O: 1% to 7%, preferably K2O: 1% to 5%, more preferably K2O: 1% to 4%.

[0013] (8) The optical glass according to any one of (1) to (4) has a composition that does not contain TiO2, and / or does not contain B2O3, and / or does not contain Al2O3, and / or does not contain CaO, and / or does not contain MgO, and / or does not contain P2O5, and / or does not contain La2O3, and / or does not contain Gd2O3, and / or does not contain Y2O3, and / or does not contain Yb2O3.

[0014] (9) The optical glass according to any one of (1) to (4) has a refractive index n d is 1.685 to 1.76, preferably 1.69 to 1.75, more preferably 1.70 to 1.74, and / or the Abbe number ν d is 31.50 to 37.50, preferably 32 to 37, and more preferably 33 to 36.

[0015] (10) The optical glass according to any one of (1) to (4) has a relative partial dispersion P g,F is 0.6000 or less, preferably 0.5900 or less, more preferably 0.5860 or less, and / or the density ρ is 3.80 g / cm 3 Preferably, it is 3.60 g / cm or less. 3 More preferably, 3.50 g / cm or less. 3 and / or 400 nm internal transmittance τ 400nm is 88.0% or more, preferably 90.0% or more, more preferably 90.5% or more, even more preferably 91.0% or more, still more preferably 92.0% or more, and even more preferably 92.5% or more, and / or the devitrification resistance is level B or more, preferably level A, and / or the thermal expansion coefficient α 20 / 120℃ is 90 x 10 -7 / K or less, preferably 85×10 -7 / K or less, and more preferably 80×10 -7 / K or less, and / or the cellularity is level A or more, preferably level A0 or more, and / or the viscosity at 1400°C is 50 poise or less, preferably 35 poise or less, more preferably 20 poise or less, and / or the transition temperature T g is 630°C or less, preferably 620°C or less, and more preferably 610°C or less.

[0016] (11) A glass preform made from the optical glass according to any one of (1) to (10).

[0017] (12) An optical element, which is manufactured from the optical glass according to any one of (1) to (10) above, or from the glass preform according to (11).

[0018] (13) An optical instrument, which contains the optical glass according to any one of (1) to (10) and / or the optical element according to (12). [Effects of the Invention]

[0019] The beneficial effect of the present invention is that, through rational composition design, the optical glass of the present invention has high light transmittance and low relative partial dispersion, which meets the application of high performance optical systems. DETAILED DESCRIPTION OF THE INVENTION

[0020]

[0033] Hereinafter, embodiments of the optical glass of the present invention will be described in detail, but the present invention is not limited to the following embodiments and can be practiced with appropriate modifications within the scope of the object of the present invention. Furthermore, duplicated explanations may be omitted where appropriate, but this does not limit the spirit of the invention, and hereinafter the optical glass of the present invention may be simply referred to as glass.

[0021] [Optical glass] The range of each composition (component) of the optical glass of the present invention will be explained below. In the present invention, unless otherwise specified, the content of each composition and the total content are all expressed in weight percentage (wt%), that is, the content of each composition and the total content are expressed as weight percentages relative to the total amount of glass material in terms of oxide composition. Here, the term "composition in terms of oxide" refers to the case where oxides, composite salts, hydroxides, etc. used as raw materials for the composition components of the optical glass of the present invention decompose to oxides during melting, and the total amount of the oxide material is taken as 100%.

[0022] The numerical ranges recited in the present invention include upper and lower limits unless otherwise specified in a specific instance, and the terms "greater than or equal to" and "less than or equal to" include the endpoints and all integers and fractions contained within the range, and are not limited to the specific values ​​recited when the range is defined. As used herein, "and / or" is inclusive, for example, "A and / or B" means A only, or B only, or both A and B.

[0023] <Essential and optional ingredients> SiO2 is an essential component of the optical glass of the present invention and is the skeleton of the optical glass of the present invention. If the SiO2 content is less than 30%, it becomes difficult to obtain a stable glass, and the chemical stability and devitrification resistance of the glass deteriorate. Therefore, in the present invention, the SiO2 content is 30% or more, preferably 35% or more, and more preferably 37% or more. If the SiO2 content exceeds 50%, the meltability of the glass deteriorates, making it difficult for the glass to obtain the desired optical constants. Therefore, the SiO2 content is 50% or less, preferably 45% or less, and more preferably 43% or less.

[0024] B2O3 has the effect of improving the meltability of glass, but if its content is too high, the chemical stability of the glass deteriorates, the viscosity of the glass decreases, and volatilization increases, which are disadvantageous in stable control of the refractive index and dispersion. Furthermore, if the B2O3 content is too high, it is disadvantageous in improving the light transmittance of the glass of the present invention. Therefore, in the present invention, the B2O3 content is 0 to 4%, preferably 0 to 2%, and more preferably 0 to 1%. In some embodiments, it is even more preferable that the glass does not contain B2O3.

[0025] Although Al2O3 can improve the chemical stability of glass, if its content exceeds 3%, the meltability and light transmittance of the glass deteriorate. Therefore, in the present invention, the Al2O3 content is 0 to 3%, preferably 0 to 2%, and more preferably 0 to 1%. In some embodiments, it is even more preferable that Al2O3 is not contained.

[0026] ZrO2 improves the refractive index of glass, improves its chemical stability, and adjusts the relative partial dispersion of glass, but if its content is too high, it becomes difficult to melt the glass, the melting temperature rises, inclusions enter the glass, and light transmittance decreases. Therefore, the ZrO2 content is 1% to 10%, preferably 3% to 8%, and more preferably 4% to 7%.

[0027] TiO2 has the effect of increasing the refractive index and dispersion of glass, and when contained in an appropriate amount, it can make the glass more stable and reduce the viscosity of the glass. If the TiO2 content exceeds 3%, the crystallization tendency of the glass increases, the relative partial dispersion of the glass increases, and the light transmittance decreases. Therefore, in the present invention, the TiO2 content is 3% or less, preferably 2% or less, and more preferably 1% or less. In some embodiments, it is even more preferable that TiO2 is not contained.

[0028] Nb2O5 is a component that improves the devitrification resistance, refractive index, and dispersion of the glass and provides anomalous dispersion. If the content is too high, the thermal stability and light transmittance of the glass tend to decrease and the liquidus temperature tends to increase. Therefore, in the present invention, the Nb2O5 content is 25% to 38%, preferably 26% to 36%, and more preferably 28% to 32%.

[0029] In some embodiments, the ratio of the SiO2 content to the Nb2O5 content, SiO2 / Nb2O5, is controlled within the range of 0.9 to 1.8, thereby achieving low relative partial dispersion of the glass, optimizing the high-temperature viscosity and chemical stability of the glass, and contributing to preventing an increase in the thermal expansion coefficient of the glass. Therefore, SiO2 / Nb2O5 is preferably 0.9 to 1.8, more preferably 1.0 to 1.6, and even more preferably 1.1 to 1.5.

[0030] Ln2O3 (Ln2O3 is one or more of La2O3, Gd2O3, Y2O3, and Yb2O3) is a component that improves the refractive index and chemical stability of glass, and by controlling the Ln2O3 content to 4% or less, it is possible to prevent a decrease in the devitrification resistance of the glass. Therefore, the Ln2O3 content is 4% or less, preferably 2% or less, and more preferably 1% or less. In some embodiments, it is more preferable that the glass does not contain La2O3, and / or does not contain Gd2O3, and / or does not contain Y2O3, and / or does not contain Yb2O3.

[0031] ZnO adjusts the refractive index and dispersion of glass, lowers the high-temperature viscosity and transition temperature of glass, allows glass to melt at a low temperature, and improves the light transmittance of glass. If the ZnO content is too high, the glass becomes more difficult to mold and its devitrification resistance deteriorates. Therefore, the ZnO content is 0 to 5%, preferably greater than 0 but not more than 3%, and more preferably 0.1 to 2%.

[0032] In some embodiments, by controlling the ratio of the ZnO content to the ZrO content (ZnO / ZrO2) to 1.0 or less, the thermal expansion coefficient and high-temperature viscosity of the glass can be optimized, and deterioration of the cellularity and relative partial dispersion of the glass can be prevented. Therefore, ZnO / ZrO2 is preferably 1.0 or less, more preferably greater than 0 and 0.8 or less, even more preferably 0.01 to 0.6, and even more preferably 0.05 to 0.5.

[0033] Although BaO can improve the abrasion resistance and hardness of the glass and reduce the refractive index temperature coefficient and thermal expansion coefficient of the glass, a high BaO content reduces the chemical stability of the glass. Therefore, the BaO content is 3% to 15%, preferably 4% to 11%, and more preferably 5% to 9%.

[0034] SrO improves the devitrification resistance and chemical stability of the glass and can reduce the density of the glass, but since SrO is expensive, if the content is too high, the cost of the glass increases. Therefore, in the present invention, the SrO content is 3% to 13%, preferably 4% to 10%, and more preferably 5% to 8%.

[0035] In some embodiments, the ratio (TiO2+B2O3+ZnO) / SrO of the total content of TiO2, B2O3, and ZnO (TiO2+B2O3+ZnO) to the content of SrO can be controlled to 1.3 or less to improve the bubble content and devitrification resistance of the glass and lower the glass transition temperature. Therefore, preferably, (TiO2+B2O3+ZnO) / SrO is 1.3 or less, more preferably, (TiO2+B2O3+ZnO) / SrO is 1.0 or less, even more preferably, (TiO2+B2O3+ZnO) / SrO is 0.01 to 0.7, and even more preferably, (TiO2+B2O3+ZnO) / SrO is 0.05 to 0.4.

[0036] CaO contributes to adjusting the optical constants of the glass, improves the processability of the glass, and reduces the density of the glass. However, if the CaO content is too high, the devitrification resistance of the glass decreases. Therefore, the CaO content is limited to 5% or less, preferably 3% or less, and more preferably 1% or less. In some embodiments, it is even more preferable that the glass does not contain CaO.

[0037] Although MgO helps improve the weather resistance of glass, if the content is too high, the refractive index of the glass will be difficult to achieve the design requirements, the devitrification resistance and stability of the glass will be reduced, and the cost of the glass will rise rapidly. Therefore, the MgO content is limited to 0 to 5%, preferably 0 to 3%, and more preferably 0 to 1%. In some embodiments, it is even more preferable that the glass does not contain MgO.

[0038] In some embodiments, the ratio (B2O3+Ln2O3) / (MgO+SrO+CaO) of the total content of B2O3 and Ln2O3 (B2O3+Ln2O3) to the total content of MgO, CaO, and SrO (MgO+SrO+CaO) can be controlled to 1.5 or less to prevent relative partial dispersion and an increase in density of the glass and improve the light transmittance of the glass. Therefore, preferably, (B2O3+Ln2O3) / (MgO+SrO+CaO) is 1.5 or less, more preferably, (B2O3+Ln2O3) / (MgO+SrO+CaO) is 1.0 or less, even more preferably, (B2O3+Ln2O3) / (MgO+SrO+CaO) is 0.5 or less, and even more preferably, (B2O3+Ln2O3) / (MgO+SrO+CaO) is 0.3 or less.

[0039] In some embodiments, controlling the ratio (Nb2O5+B2O3+ZnO) / (MgO+SrO+CaO+BaO) of the total content of Nb2O5, B2O3, and ZnO, Nb2O5+B2O3+ZnO, to the total content of MgO, CaO, SrO, and BaO, MgO+SrO+CaO+BaO, within the range of 0.9 to 5.5 is advantageous in reducing the high-temperature viscosity and transition temperature of the glass and improving the chemical stability of the glass. Therefore, preferably, (Nb2O5 + B2O3 + ZnO) / (MgO + SrO + CaO + BaO) is 0.9 to 5.5, more preferably, (Nb2O5 + B2O3 + ZnO) / (MgO + SrO + CaO + BaO) is 1.0 to 5.0, even more preferably, (Nb2O5 + B2O3 + ZnO) / (MgO + SrO + CaO + BaO) is 1.2 to 4.0, and even more preferably, (Nb2O5 + B2O3 + ZnO) / (MgO + SrO + CaO + BaO) is 1.5 to 3.0.

[0040] In some embodiments, by controlling the ratio (MgO+SrO+CaO+BaO) / (Nb2O5+TiO2) of the total content of MgO, CaO, SrO, and BaO (MgO+SrO+CaO+BaO) to the total content of Nb2O5 and TiO2 (Nb2O5+TiO2) within the range of 0.2 to 1.2, it is possible to optimize the cellularity and thermal expansion coefficient of the glass and prevent increases in the density and transition temperature of the glass. Therefore, preferably, (MgO+SrO+CaO+BaO) / (Nb2O5+TiO2) is 0.2 to 1.2, more preferably, (MgO+SrO+CaO+BaO) / (Nb2O5+TiO2) is 0.25 to 1.0, even more preferably, (MgO+SrO+CaO+BaO) / (Nb2O5+TiO2) is 0.3 to 0.8, and even more preferably, (MgO+SrO+CaO+BaO) / (Nb2O5+TiO2) is 0.3 to 0.6.

[0041] An appropriate amount of alkali metal oxide RnO (RnO is the total content of LiO, NaO, and KO) reduces the melting difficulty of the glass, making it easier for the refractive index, Abbe number, and relative partial dispersion to meet design requirements. If the RnO content is less than 5%, the above effects are not significant, and if the RnO content exceeds 20%, the devitrification resistance of the glass rapidly deteriorates. Therefore, the RnO content is 5% to 20%, preferably 6% to 18%, and more preferably 7% to 15%.

[0042] Although Li2O can lower the glass transition temperature, adjust the high-temperature viscosity of glass, and improve the meltability of glass, a high Li2O content is detrimental to the chemical stability of glass. Therefore, in the present invention, the Li2O content is 1% to 7%, preferably 1% to 5%, and more preferably 1% to 4%.

[0043] Na2O has the effect of improving the meltability of glass, enhancing the glass melting effect, and contributing to a decrease in the relative partial dispersion of the glass, but if its content is too high, the chemical stability and weather resistance of the glass will decrease. Therefore, the Na2O content is 2% to 9%, preferably 2% to 7%, and more preferably 2% to 6%.

[0044] In some embodiments, by controlling the ratio (Na2O+BaO) / (Li2O+SrO) of the total content of Na2O and BaO (Na2O+BaO) to the total content of Li2O and SrO (Li2O+SrO) within the range of 0.4 to 5.0, the glass has excellent resistance to devitrification and high-temperature viscosity, and a decrease in the light transmittance of the glass can be prevented. Therefore, preferably, (Na2O+BaO) / (Li2O+SrO) is 0.4 to 5.0, more preferably, (Na2O+BaO) / (Li2O+SrO) is 0.5 to 3.5, even more preferably, (Na2O+BaO) / (Li2O+SrO) is 0.7 to 2.5, and even more preferably, (Na2O+BaO) / (Li2O+SrO) is 0.9 to 2.0.

[0045] Although K2O has the effect of improving the thermal stability and meltability of glass, if its content is too high, the devitrification resistance and chemical stability of the glass decrease. Therefore, in the present invention, the K2O content is 1% to 7%, preferably 1% to 5%, and more preferably 1% to 4%.

[0046] In some embodiments, the chemical stability and light transmittance of the glass can be improved and a decrease in the devitrification resistance of the glass can be prevented by controlling the ratio Li2O / (Na2O+K2O) of the Li2O content to the total content of Na2O and K2O (Na2O+K2O) within the range of 0.1 to 2.0. Therefore, Li2O / (Na2O+K2O) is preferably 0.1 to 2.0, more preferably 0.2 to 1.5, even more preferably 0.2 to 1.0, and even more preferably 0.3 to 0.7.

[0047] In some embodiments, by controlling the ratio (RnO / SrO) of the total content (RnO) of Li2O, Na2O, and K2O to the content (SrO) within the range of 0.5 to 4.5, the high-temperature viscosity of the glass can be reduced, the light transmittance can be optimized, and an increase in the glass transition temperature can be prevented. Therefore, preferably, Rn2O / SrO is 0.5 to 4.5, more preferably, Rn2O / SrO is 0.6 to 4.0, even more preferably, Rn2O / SrO is 0.8 to 3.0, and even more preferably, Rn2O / SrO is 1.0 to 2.5.

[0048] Although P2O5 can adjust the Abbe number of the glass, in this type of glass, if the P2O5 content exceeds 3%, a large number of crystal nuclei are formed in the glass, rapidly deteriorating the devitrification resistance of the glass. Therefore, the P2O5 content is limited to 3% or less, preferably 2% or less, and more preferably 1% or less. In some embodiments, it is even more preferable that the glass does not contain P2O5.

[0049] In the present invention, the inclusion of 0-1% of one or more of Sb2O3, SnO, SnO2, and CeO2 as a fining agent can improve the fining effect of the glass and increase the cellularity of the glass. Preferably, the content of the fining agent is 0-0.5%, more preferably 0-0.1%. If the Sb2O3 content exceeds 1%, the fining ability of the glass tends to decrease, and its strong oxidizing effect accelerates corrosion of the platinum or platinum alloy vessel used to melt the glass and deterioration of the molding die. Therefore, in the present invention, the Sb2O3 content is preferably 0-1%, more preferably 0-0.5%, and even more preferably 0-0.1%. SnO and SnO2 may 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 or the like, Sn tends to act as a starting point for crystal nucleation, resulting in devitrification. Therefore, the content of SnO2 in the present invention is preferably 0 to 1%, more preferably 0 to 0.5%, and even more preferably 0 to 0.1%, and the content of SnO is preferably 0 to 1%, more preferably 0 to 0.5%, and even more preferably 0 to 0.1%. The function and content of CeO2 are similar to those of SnO2, and its content is preferably 0 to 1%, more preferably 0 to 0.5%, and even more preferably 0 to 0.1%, and even more preferably CeO2 is not contained.

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

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

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

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

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

[0055] <Refractive index and Abbe number> The refractive index of optical glass (n d ) and Abbe number (ν d ) is measured according to the method specified in GB / T 7962.1-2010.

[0056] In some embodiments, the refractive index (n d The lower limit of ) is 1.685, preferably 1.69, and more preferably 1.70.

[0057] In some embodiments, the refractive index (n d ) is 1.76, preferably 1.75, and more preferably 1.74.

[0058] In some embodiments, the Abbe number (ν d The lower limit of ) is 31.50, preferably 32, and more preferably 33.

[0059] In some embodiments, the Abbe number (ν d ) is 37.50, preferably 37, and more preferably 36.

[0060] <density> The density (ρ) of optical glass is measured according to the method specified in GB / T7962.20-2010.

[0061] In some embodiments, the density (ρ) of the optical glass of the present invention is 3.80 g / cm 3 Preferably, it is 3.60 g / cm or less. 3 More preferably, 3.50 g / cm or less. 3 The following is the result.

[0062] <400nm internal transmittance> 400nm internal transmittance (τ 400nm ) is measured according to the method specified in GB / T 7962.12-2010, and the thickness of the glass sample is 10 mm.

[0063] In some embodiments, the 400 nm internal transmittance (τ 400nm ) is 88.0% or more, preferably 90.0% or more, more preferably 90.5% or more, even more preferably 91.0% or more, still more preferably 92.0% or more, and even more preferably 92.5% or more.

[0064] <Relative partial variance> Relative partial dispersion (P g,F )=(n g -n F ) / (n F -nC ).

[0065] In some embodiments, the optical glasses of the present invention have a relative partial dispersion (P g,F ) is 0.6000 or less, preferably 0.5900 or less, and more preferably 0.5860 or less.

[0066] <Strong acid resistance> In this invention, the acid resistance / chemical stability of glass is expressed by its strong acid resistance. The test method involves polishing a large surface of a 30 x 30 x 10 mm glass sample, immersing it in an acid solution with a pH of 2.0, and removing it every 5 hours to observe whether corrosion pits were present on the surface. The longer the time from immersion until corrosion pits appeared, the higher the acid resistance of the glass.

[0067] In some embodiments, the optical glass of the present invention exhibits a time from immersion in an acid solution until corrosion pits appear of 60 hours or more, preferably 80 hours or more, and more preferably 100 hours or more.

[0068] <Devitrification resistance performance> The devitrification resistance of the glass of the present invention is determined as follows.

[0069] The experimental glass sample was processed to a standard size of 20 × 20 × 10 mm, polished on both sides, and heated to a temperature of T g The glass was placed in a crystallization furnace at +200°C and kept at this temperature for 30 minutes. After removing it and cooling, the two large surfaces were polished and the crystallization performance of the glass was judged according to Table 1 below, with Level A being the best and Level E being the worst.

[0070] Table 1. Classification and judgment criteria for crystallization levels [Table 1]

[0071] In some embodiments, the devitrification resistance of the optical glass of the present invention is Level B or higher, and preferably Level A.

[0072] <Thermal expansion coefficient> The thermal expansion coefficient of optical glass (α 20 / 120℃ ) is measured at temperatures between 20°C and 120°C for optical glass according to the method specified in GB / T 7962.16-2010.

[0073] In some embodiments, the coefficient of thermal expansion (α 20 / 120℃ ) is 90 x 10 -7 / K or less, preferably 85×10 -7 / K or less, and more preferably 80×10 -7 / K or less.

[0074] <Bubble content> The bubble content of optical glass is measured according to the method specified in GB / T7962.8-2010.

[0075] In some embodiments, the cellular content of the optical glass of the present invention is level A or higher, preferably level A0 or higher.

[0076] <High temperature viscosity> The high temperature viscosity of optical glass is measured by the following method: The high temperature viscosity of glass is measured by the rotational method using a THETA Rheotronic II high temperature viscometer, and the numerical unit is dPaS (poise), with the smaller the numerical value, the lower the viscosity.

[0077] In some embodiments, the optical glass of the present invention has a viscosity at 1400° C. of 50 poise or less, preferably 35 poise or less, and more preferably 20 poise or less.

[0078] <Transition temperature> Optical glass transition temperature (T g ) is measured according to the method specified in GB / T7962.16-2010.

[0079] In some embodiments, the optical glass of the present invention has a transition temperature (T g) is 630°C or less, preferably 620°C or less, and more preferably 610°C or less.

[0080] [Optical glass manufacturing method] The method for producing the optical glass of the present invention is as follows. The glass of the present invention is produced using conventional raw materials and processes, including, but not limited to, oxides, hydroxides, complex salts (e.g., carbonates, nitrates, sulfates, phosphates, metaphosphates, etc.), boric acid, etc., by blending the raw materials in a conventional manner, and then charging the blended furnace material into a melting furnace (e.g., a platinum or platinum alloy crucible) at 1200 to 1500°C for melting. After undergoing fining and homogenization, a homogeneous molten glass free of bubbles and undissolved materials is obtained, and this molten glass is then cast into a mold and annealed to produce the glass. Those skilled in the art will be able to appropriately select the raw materials, process methods, and process parameters according to actual needs.

[0081] [Glass preforms and optical elements] From the produced optical glass, a glass preform can be produced, for example, by direct gob molding, polishing, or press molding such as hot press molding. That is, a glass precision preform can be produced by directly subjecting molten optical glass to precision gob molding, by subjecting the molten optical glass to mechanical processing such as grinding and polishing, or by producing a preform for press molding from the optical glass, re-hot press molding the preform, and then polishing the preform. Note that the means for producing a glass preform are not limited to those described above.

[0082] As described above, the optical glass of the present invention is useful for various optical elements and optical designs, and it is particularly preferable to form a preform from the optical glass of the present invention and use the preform to carry out reheat press molding, precision press molding, or the like to produce optical elements such as lenses and prisms.

[0083] The glass preform and optical element of the present invention are both formed from the optical glass of the present invention. The glass preform of the present invention has the excellent properties of optical glass, and the optical element of the present invention has the excellent properties of optical glass, making it possible to provide optical elements such as various lenses and prisms with high optical value.

[0084] Examples of lenses include various lenses whose lens surfaces are spherical or aspherical, such as concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, and plano-concave lenses.

[0085] The optical glass of the present invention can be used to produce optical elements such as glass wafers for AR / MR technology and tempered glass wafers.

[0086] [Optical equipment] The optical glass or optical element formed from the optical glass of the present invention can be used to produce optical equipment such as photography equipment, image capture equipment, display equipment, and monitoring equipment. The optical glass or optical element of the present invention is suitable for use in automotive lighting equipment and optical equipment, and is applied to fields such as automotive applications. The optical glass or optical element of the present invention is suitable for use in optical equipment such as microprojection, microimaging (image capture / photography), and microlighting.

[0087] Example <Examples of optical glass> In order to further clearly interpret and explain the technical solutions of the present invention, the following non-limiting examples are provided.

[0088] In this example, the optical glass manufacturing method described above is used to obtain optical glasses having the compositions shown in Tables 2 to 4. In addition, the properties of each glass are measured using the measurement methods described in the present invention, and the measurement results are shown in Tables 2 to 4.

[0089] Table 2. [Table 2] TIFF2025130047000003.tif73170

[0090] Table 3. [Table 3] TIFF2025130047000005.tif73170

[0091] Table 4. [Table 4] TIFF2025130047000007.tif74170

[0092] <Example of glass preform> From the glasses obtained in Examples 1# to 24# of optical glasses, various lenses such as concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, and plano-concave lenses, as well as preforms such as prisms, are manufactured using, for example, polishing means or press molding means such as reheat press molding and precision press molding.

[0093] <Example of optical element> These preforms obtained in the above glass preform examples are annealed to fine-tune the refractive index while reducing the stress inside the glass so that the optical properties such as the refractive index reach the desired values.

[0094] Next, each preform is ground and polished to produce various lenses and prisms, such as concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, and plano-concave lenses. An anti-reflection film can also be applied to the surface of the obtained optical element.

[0095] <Example of optical equipment> Optical elements manufactured from the above optical element embodiments can be used in optical designs to form optical components or optical assemblies using one or more optical elements, which can be used in, for example, imaging equipment, sensors, microscopes, medical technology, digital projection, communications, optical communication technology / information transmission, optics / illumination in the automotive field, lithography technology, excimer lasers, wafers, computer chips, and integrated circuits and electronic devices containing such circuits and chips.

Claims

1. The composition expressed in weight percentage is SiO ２ :30%~50%, Nb ２ O ５ :25%~38%, ZrO ２ : 1% to 10%, BaO: 3% to 15%, SrO: 3% to 13%, Rn ２ O: Contains 5% to 20%, (Na ２ O+BaO) / (Li ２ O+SrO) is 0.4 to 5.0, and the Rn ２ O is Li ２ O, Na ２ O.K. ２ 1. An optical glass comprising:

2. When the composition is expressed in weight percentage, B ２ O ３ : 0 to 4%, and / or Al ２ O ３ : 0 to 3%, and / or TiO ２ : 0 to 3%, and / or Ln ２ O ３ : 0 to 4%, and / or ZnO: 0 to 5%, and / or CaO: 0 to 5%, and / or MgO: 0 to 5%, and / or P ２ O ５ : 0 to 3%, and / or fining agent: 0 to 1%, ２ O ３ Is, La ２ O ３ , Gd ２ O ３ , Y ２ O ３ , Yb ２ O ３ The fining agent is one or more of Sb ２ O ３ , SnO, SnO ２ , CeO ２ 2. The optical glass according to claim 1, wherein the optical glass is one or more of the following:

3. Optical glass, the composition of which is SiO ２ , Nb ２ O ５ , ZrO ２ , BaO, SrO and Rn ２ O is contained, and when the composition is expressed in weight percentage, 5% to 20% of Rn ２ Contains O, (Na ２ O+BaO) / (Li ２ O+SrO) is 0.4 to 5.0, and the Rn ２ O is Li ２ O, Na ２ O.K. ２ The total content of O is 0, and the optical glass has a refractive index n ｄ is 1.685 to 1.76, and the Abbe number ν ｄ is 31.50 to 37.50, and the 400 nm internal transmittance τ ４００ｎｍ % or more.

4. The composition expressed in weight percentage is SiO ２ : 30% to 50%, and / or Nb ２ O ５ : 25% to 38%, and / or ZrO ２ : 1% to 10%, and / or BaO: 3% to 15%, and / or SrO: 3% to 13%, and / or B ２ O ３ : 0 to 4%, and / or Al ２ O ３ : 0 to 3%, and / or TiO ２ : 0 to 3%, and / or Ln ２ O ３ : 0 to 4%, and / or ZnO: 0 to 5%, and / or CaO: 0 to 5%, and / or MgO: 0 to 5%, and / or P ２ O ５ : 0 to 3%, and / or fining agent: 0 to 1%, ２ O ３ Is, La ２ O ３ , Gd ２ O ３ , Y ２ O ３ , Yb ２ O ３ The fining agent is one or more of Sb ２ O ３ , SnO, SnO ２ , CeO ２ 4. The optical glass according to claim 3, wherein the optical glass is one or more of the following:

5. When the composition is expressed as a weight percentage, 1) SiO ２ / Nb ２ O ５ is between 0.9 and 1.8, 2) (Na ２ O+BaO) / (Li ２ O + SrO) is 0.5 to 3.5, 3) (TiO ２ +B ２ O ３ +ZnO) / SrO is 1.3 or less, 4) (B ２ O ３ +Ln ２ O ３ ) / (MgO+SrO+CaO) is 1.5 or less, 5) (Nb ２ O ５ +B ２ O ３ + ZnO) / (MgO+SrO+CaO+BaO) is 0.9 to 5.5, 6) ZnO / ZrO ２ is less than or equal to 1.0, 7) (MgO+SrO+CaO+BaO) / (Nb ２ O ５ + TiO ２ ) is 0.2 to 1.2, 8) Li ２ O / (Na ２ O+K ２ O) is 0.1 to 2.0, 9) Rn ２ One or more of the following nine conditions is satisfied: O / SrO is 0.5 to 4.5; Said Rn ２ O is Li ２ O, Na ２ O.K. ２ is the total content of O, and Ln ２ O ３ Is, La ２ O ３ , Gd ２ O ３ , Y ２ O ３ , Yb ２ O ３ 5. The optical glass according to claim 1, wherein the optical glass is one or more of the following:

6. When the composition is expressed as a weight percentage, 1) SiO ２ / Nb ２ O ５ is between 1.0 and 1.6, 2) (Na ２ O+BaO) / (Li ２ O + SrO) is 0.7 to 2.5, 3) (TiO ２ +B ２ O ３ +ZnO) / SrO is 0.01 to 0.7, 4) (B ２ O ３ +Ln ２ O ３ ) / (MgO+SrO+CaO) is 0.5 or less, 5) (Nb ２ O ５ +B ２ O ３ + ZnO) / (MgO+SrO+CaO+BaO) is 1.2 to 4.0, 6) ZnO / ZrO ２ is 0.01 to 0.6, 7) (MgO+SrO+CaO+BaO) / (Nb ２ O ５ + TiO ２ ) is 0.3 to 0.8, 8) Li ２ O / (Na ２ O+K ２ O) is 0.2 to 1.0, 9) Rn ２ One or more of the following nine conditions is satisfied: O / SrO is 0.8 to 3.0; Said Rn ２ O is Li ２ O, Na ２ O.K. ２ is the total content of O, and Ln ２ O ３ Is, La ２ O ３ , Gd ２ O ３ , Y ２ O ３ , Yb ２ O ３ 5. The optical glass according to claim 1, wherein the optical glass is one or more of the following:

7. When the composition is expressed as a weight percentage, 1) SiO ２ / Nb ２ O ５ is between 1.1 and 1.5, 2) (Na ２ O+BaO) / (Li ２ O + SrO) is 0.9 to 2.0, 3) (TiO ２ +B ２ O ３ +ZnO) / SrO is 0.05 to 0.4, 4) (B ２ O ３ +Ln ２ O ３ ) / (MgO+SrO+CaO) is 0.3 or less, 5) (Nb ２ O ５ +B ２ O ３ + ZnO) / (MgO+SrO+CaO+BaO) is 1.5 to 3.0, 6) ZnO / ZrO ２ is between 0.05 and 0.5, 7) (MgO+SrO+CaO+BaO) / (Nb ２ O ５ + TiO ２ ) is 0.3 to 0.6, 8) Li ２ O / (Na ２ O+K ２ O) is 0.3 to 0.7, 9) Rn ２ One or more of the following nine conditions is satisfied: O / SrO is 1.0 to 2.5; Said Rn ２ O is Li ２ O, Na ２ O.K. ２ is the total content of O, and Ln ２ O ３ Is, La ２ O ３ , Gd ２ O ３ , Y ２ O ３ , Yb ２ O ３ 5. The optical glass according to claim 1, wherein the optical glass is one or more of the following:

8. The composition expressed in weight percentage is SiO ２ : 35% to 45%, and / or Nb ２ O ５ : 26% to 36%, and / or ZrO ２ : 3% to 8%, and / or BaO: 4% to 11%, and / or SrO: 4% to 10%, and / or Rn ２ O: 6% to 18%, and / or B ２ O ３ : 0 to 2%, and / or Al ２ O ３ : 0 to 2%, and / or TiO ２ : 0 to 2%, and / or Ln ２ O ３ : 0 to 2%, and / or ZnO: greater than 0 and not more than 3%, and / or CaO: 0 to 3%, and / or MgO: 0 to 3%, and / or P ２ O ５ : 0 to 2%, and / or fining agent: 0 to 0.5%, and the Rn ２ O is Li ２ O, Na ２ O.K. ２ The total content of O, ２ O ３ Is, La ２ O ３ , Gd ２ O ３ , Y ２ O ３ , Yb ２ O ３ The fining agent is one or more of Sb ２ O ３ , SnO, SnO ２ , CeO ２ 5. The optical glass according to claim 1, wherein the optical glass is one or more of the following:

9. The composition expressed in weight percentage is SiO ２ : 37% to 43%, and / or Nb ２ O ５ : 28% to 32%, and / or ZrO ２ : 4% to 7%, and / or BaO: 5% to 9%, and / or SrO: 5% to 8%, and / or Rn ２ O: 7% to 15%, and / or B ２ O ３ : 0 to 1%, and / or Al ２ O ３ : 0 to 1%, and / or TiO ２ : 0 to 1%, and / or Ln ２ O ３ : 0 to 1%, and / or ZnO: 0.1 to 2%, and / or CaO: 0 to 1%, and / or MgO: 0 to 1%, and / or P ２ O ５ : 0 to 1%, and / or fining agent: 0 to 0.1%, and the Rn ２ O is Li ２ O, Na ２ O.K. ２ The total content of O, ２ O ３ Is, La ２ O ３ , Gd ２ O ３ , Y ２ O ３ , Yb ２ O ３ The fining agent is one or more of Sb ２ O ３ , SnO, SnO ２ , CeO ２ 5. The optical glass according to claim 1, wherein the optical glass is one or more of the following:

10. When the composition is expressed in weight percentage, Li ２ O: 1% to 7% and / or Na ２ O: 2% to 9% and / or K ２ 5. The optical glass according to claim 1, wherein O is 1% to 7%.

11. When the composition is expressed in weight percentage, Li ２ O: 1% to 4% and / or Na ２ O: 2% to 6% and / or K ２ 5. The optical glass according to claim 1, wherein O is 1% to 4%.

12. The composition is TiO ２ and / or B ２ O ３ and / or Al ２ O ３ and / or does not contain CaO, and / or does not contain MgO, and / or does not contain P ２ O ５ and / or does not contain La ２ O ３ and / or Gd ２ O ３ and / or Y ２ O ３ and / or Yb ２ O ３ 5. The optical glass according to claim 1, wherein the optical glass does not contain:

13. The refractive index n of the optical glass ｄ is 1.685 to 1.76, and / or the Abbe number ν ｄ is 31.50 to 37.50, and / or the relative partial dispersion P ｇ，Ｆ is 0.6000 or less, and / or the density ρ is 3.80 g / cm ３ and / or the 400 nm internal transmittance τ ４００ｎｍ is 90.0% or more, and / or the devitrification resistance is level B or more, and / or the thermal expansion coefficient α ２０／１２０℃ is 90 x 10 －７ / K or less, and / or the porosity is level A or more, and / or the viscosity at 1400°C is 50 poise or less, and / or the transition temperature T ｇ 5. The optical glass according to claim 1, wherein the temperature is 630° C. or lower.

14. The refractive index n of the optical glass ｄ is 1.70 to 1.74, and / or the Abbe number ν ｄ is 33 to 36, and / or the relative partial dispersion P ｇ，Ｆ is 0.5860 or less, and / or the density ρ is 3.50 g / cm ３ and / or the 400 nm internal transmittance τ ４００ｎｍ is 92.5% or more, and / or the devitrification resistance is level A, and / or the thermal expansion coefficient α ２０／１２０℃ is 80 x 10 －７ / K or less, and / or the foaming level is level A ０ and / or the viscosity at 1400°C is 20 poise or less, and / or the transition temperature T ｇ 5. The optical glass according to claim 1, wherein the temperature is 610° C. or lower.

15. A glass preform, characterized in that it is produced from the optical glass according to any one of claims 1 to 4.

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

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

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