Optical glass, optical elements, and optical devices

Abstract

The present invention provides an optical glass. The optical glass contains, as components, 1 to 15% of SiO2, 5 to 25% of B2O3, 2 to 15% of ZrO2, 3 to 20% of Nb2O5, and 45 to 75% of La2O3+Y2O3+Gd2O3 in weight percentage. By reasonable component design, the present invention can obtain an optical glass with excellent devitrification resistance at low raw material cost.

Description

Technical Field

[0001] The present invention relates to optical glass, and in particular, to optical glass having a refractive index of 1.87 to 1.94 and an Abbe number of 33 to 41, as well as a glass molded body, an optical element, and an optical device manufactured from the optical glass.

Background Art

[0002] Currently, with the rapid development of science and technology, devices such as digital cameras, digital video cameras, and photographable mobile phones are becoming increasingly popular. Taking a digital camera as an example, a plurality of spherical lenses are required within one lens. However, instead of a plurality of spherical lenses, one aspherical lens processed from optical glass with a high refractive index can be used, significantly reducing the weight of the lens. Lenses formed from optical glass with a high refractive index can miniaturize and lighten the optical system. In particular, optical glass having a refractive index of 1.87 to 1.94 and an Abbe number of 33 to 41 is seeing an increasingly high market demand.

[0003] The optical glass disclosed in CN103288344A, having a refractive index of 1.86 to 1.90 and an Abbe number of 35 to 40, contains 13 to 20% of ZnO, 7 to 15% of Ta2O5, and 9 to 17% of WO3. Ta2O5 is a rare metal component, and a high content of Ta2O5 is disadvantageous for cost control of optical glass. Moreover, high contents of ZnO and WO3 have an adverse effect on the devitrification resistance of the glass. Therefore, obtaining optical glass with excellent devitrification resistance at a relatively low cost has become the goal of optical glass research.

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 with low raw material costs and excellent devitrification resistance.

Means for Solving the Problems

[0005] The technical means used by the present invention to solve the technical problems are as follows.

[0006] The optical glass contains, as components, in weight percentage, 1 to 15% of SiO2, 5 to 25% of B2O3, 2 to 15% of ZrO2, 3 to 20% of Nb2O5, and 45 to 75% of La2O3 + Y2O3 + Gd2O3.

[0007] Furthermore, the optical glass further contains, as components, in weight percentage, 0 to 10% of TiO2, and / or 0 to 5% of Ta2O5, and / or 0 to 8% of RO, and / or 0 to 8% of Rn2O, and / or 0 to 5% of WO3, and / or 0 to 10% of ZnO, and / or 0 to 8% of Al2O3, and / or 0 to 10% of Yb2O3, and / or 0 to 5% of GeO2, and / or 0 to 2% of a fining agent. The RO is one or more of MgO, CaO, SrO, and BaO. The Rn2O is one or more of Li2O, Na2O, and K2O. The fining agent is one or more of Sb2O3, SnO, SnO2, and CeO2.

[0008] The optical glass contains, as components, in weight percentage, 1 to 15% of SiO2, 5 to 25% of B2O3, 2 to 15% of ZrO2, 3 to 20% of Nb2O5, 45 to 75% of La2O3 + Y2O3 + Gd2O3, 0 to 10% of TiO2, 0 to 5% of Ta2O5, 0 to 8% of RO, 0 to 8% of Rn2O, 0 to 5% of WO3, 0 to 10% of ZnO, 0 to 8% of Al2O3, 0 to 10% of Yb2O3, 0 to 5% of GeO2, and 0 to 2% of a fining agent. The RO is one or more of MgO, CaO, SrO, and BaO. The Rn2O is one or more of Li2O, Na2O, and K2O. The fining agent is one or more of Sb2O3, SnO, SnO2, and CeO2.

[0009] Furthermore, in the optical glass, the components are in weight percentages, and (SiO2 + Y2O3) / B2O3 is 0.5 to 5.0, preferably (SiO2 + Y2O3) / B2O3 is 0.7 to 3.0, more preferably (SiO2 + Y2O3) / B2O3 is 1.0 to 2.5, and even more preferably (SiO2 + Y2O3) / B2O3 satisfies 1.0 to 2.0.

[0010] Furthermore, in the optical glass, the components are in weight percentages, and Y2O3 / (SiO2 + ZrO2) is 0.3 to 3.5, preferably Y2O3 / (SiO2 + ZrO2) is 0.4 to 3.0, more preferably Y2O3 / (SiO2 + ZrO2) is 0.5 to 2.5, and even more preferably Y2O3 / (SiO2 + ZrO2) satisfies 0.5 to 2.0.

[0011] Furthermore, in the optical glass, the components are in weight percentages, and (Y2O3 + Nb2O5) / La2O3 is 0.2 to 1.0, preferably (Y2O3 + Nb2O5) / La2O3 is 0.25 to 0.8, more preferably (Y2O3 + Nb2O5) / La2O3 is 0.3 to 0.7, and even more preferably (Y2O3 + Nb2O5) / La2O3 satisfies 0.35 to 0.65.

[0012] Furthermore, in the optical glass, the components are in weight percentages, and Nb2O5 / B2O3 is 0.2 to 2.5, preferably Nb2O5 / B2O3 is 0.4 to 2.0, more preferably Nb2O5 / B2O3 is 0.5 to 1.8, and even more preferably Nb2O5 / B2O3 satisfies 0.6 to 1.5.

[0013] Furthermore, in the optical glass, the components are in weight percentages, and TiO2 / (Y2O3 + Nb2O5) is 1.0 or less, preferably TiO2 / (Y2O3 + Nb2O5) is 0.8 or less, more preferably TiO2 / (Y2O3 + Nb2O5) is 0.5 or less, and even more preferably TiO2 / (Y2O3 + Nb2O5) satisfies 0.3 or less.

[0014] Furthermore, in the optical glass, the components, by weight percentage, satisfy that (RO + Rn2O) / SiO2 is 1.5 or less, preferably (RO + Rn2O) / SiO2 is 1.0 or less, more preferably (RO + Rn2O) / SiO2 is 0.8 or less, and even more preferably (RO + Rn2O) / SiO2 is 0.5 or less, where RO is one or more of MgO, CaO, SrO, and BaO, and Rn2O is one or more of Li2O, Na2O, and K2O.

[0015] Furthermore, in the optical glass, the components, by weight percentage, satisfy that ZnO / Y2O3 is 1.0 or less, preferably ZnO / Y2O3 is 0.8 or less, more preferably ZnO / Y2O3 is 0.5 or less, and even more preferably ZnO / Y2O3 is 0.2 or less.

[0016] Furthermore, in the optical glass, the components, by weight percentage, satisfy that (Ta2O5 + Gd2O3) / Nb2O5 is 2.0 or less, preferably (Ta2O5 + Gd2O3) / Nb2O5 is 1.5 or less, more preferably (Ta2O5 + Gd2O3) / Nb2O5 is 1.0 or less, and even more preferably (Ta2O5 + Gd2O3) / Nb2O5 is 0.8 or less.

[0017] Furthermore, the optical glass contains, as components, in weight percentage, 2 to 12% of SiO2, preferably 4 to 10% of SiO2, and / or 7 to 20% of B2O3, preferably 9 to 16% of B2O3, and / or 50 to 75% of La2O3 + Y2O3 + Gd2O3, preferably 55 to 70% of La2O3 + Y2O3 + Gd2O3, more preferably 60 to 70% of La2O3 + Y2O3 + Gd2O3, and / or 3 to 12% of ZrO2, preferably 4 to 10% of ZrO2, and / or 5 to 15% of Nb2O5, preferably 7 to 11% of Nb2O5, and / or 0 to 3% of Ta2O5, preferably 0 to 1% of Ta2O5, and / or 0 to 8% of TiO2, preferably 0 to 5% of TiO2, and / or 0 to 3% of RO, preferably 0 to 2% of RO, and / or 0 to 3% of Rn2O, preferably 0 to 2% of Rn2O, and / or 0 to 3% of WO3, preferably 0 to 2% of WO3, and / or 0 to 5% of ZnO, preferably 0 to 2% of ZnO, and / or 0 to 4% of Al2O3, preferably 0 to 2% of Al2O3, and / or 0 to 5% of Yb2O3, preferably 0 to 3% of Yb2O3, and / or 0 to 3% of GeO2, preferably 0 to 1% of GeO2, and / or 0 to 1% of fining agent, preferably 0 to 0.5% of fining agent. The RO is one or more of MgO, CaO, SrO, and BaO. The Rn2O is one or more of Li2O, Na2O, and K2O. The fining agent is one or more of Sb2O3, SnO, SnO2, and CeO2.

[0018] Furthermore, the optical glass contains, as components, in weight percentage, 35 to 65% of La2O3, preferably 40 to 60% of La2O3, more preferably 42 to 55% of La2O3, and / or 4 to 25% of Y2O3, preferably 6 to 22% of Y2O3, more preferably 8 to 20% of Y2O3, still more preferably 11 to 20% of Y2O3, and / or 0 to 10% of Gd2O3, preferably 0 to 7% of Gd2O3, more preferably 0 to 5% of Gd2O3.

[0019] Furthermore, the optical glass does not contain WO3, and / or Ta2O5, and / or RO, and / or Rn2O, and / or ZnO, and / or Al2O3, and / or GeO2 as components, where RO is one or more of MgO, CaO, SrO, and BaO, and Rn2O is one or more of Li2O, Na2O, and K2O.

[0020] Furthermore, in the optical glass, the refractive index n d is 1.87 to 1.94, preferably 1.88 to 1.92, more preferably 1.89 to 1.91, and the Abbe number ν d is 33 to 41, preferably 35 to 40, more preferably 36 to 39.

[0021] Furthermore, in the optical glass, the coefficient of thermal expansion α 20 / 120℃ is 95×10 -7 / K or less, preferably 90×10 -7 / K or less, more preferably 80×10 -7 / K or less, and / or the stability D against the action of water W is two or more, preferably one, and / or λ 70 is 410 nm or less, preferably 400 nm or less, more preferably 395 nm or less, and / or λ5 is 370 nm or less, preferably 360 nm or less, more preferably 355 nm, and / or the weather resistance CR is two or more, preferably one, and / or the Knoop hardness H K is 670×10 7 Pa or more, preferably 680×10 7 Pa or more, more preferably 690×10 7 Pa or more, and / or the Young's modulus E is 10000×10 7 Pa to 14000×10 7 Pa, preferably 11000×10 7 Pa to 13500×10 7 Pa, more preferably 11500×10 7 Pa to 13000×10 7It is Pa, and / or the bubble degree is Class A or above, preferably Class A0 or above, and more preferably Class A. 00 It is at the Class A level.

[0022] The glass molded body is manufactured from the above optical glass.

[0023] The optical element is manufactured from the above optical glass or the above glass molded body.

[0024] The optical device includes the above optical glass and / or the above optical element.

Advantages of the Invention

[0025] The beneficial effects of the present invention are as follows. Through reasonable component design, the present invention can obtain an optical glass with excellent devitrification resistance at a low raw material cost.

Embodiments for Carrying out the Invention

[0026] Hereinafter, embodiments of the optical glass of the present invention will be described in detail. However, the present invention is not limited to the following embodiments and can be appropriately modified and implemented within the scope of the object of the present invention. Also, for duplicate explanations, the explanations may be omitted as appropriate, but this does not limit the gist of the present invention. In the following content, the optical glass of the present invention may be abbreviated as glass.

[0027] [Optical Glass] Hereinafter, the range of each component (element) of the optical glass of the present invention will be described. In the present invention, unless otherwise specified, the content and total content of each component are all expressed in weight percentage (wt%), that is, the content and total content of each component are expressed as the weight percentage with respect to the total amount of the glass substance in the oxide-converted composition. Here, the "oxide-converted composition" 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 into oxides during melting, and the total amount of the oxides is set to 100%.

[0028] Unless otherwise specified in a particular case, the numerical ranges described in the present invention include the upper and lower limits, and "above" and "below" include the end values, as well as all integers and fractions within the range, and are not limited to the specific values described in the limited range. In this specification, "and / or" is inclusive. For example, "A and / or B" means only A, only B, or both A and B.

[0029] <Essential components and optional components> SiO2 has the effect of adjusting the optical constants, improving the chemical stability of the glass, maintaining a viscosity suitable for the molten glass, and reducing the abrasion degree and erosion of the refractory material. In the present invention, the above effects are obtained by containing 1% or more of SiO2. Preferably, the content of SiO2 is 2% or more, and more preferably 4% or more. If the content of SiO2 is too high, it becomes difficult to melt the glass and the transition temperature becomes high. Therefore, the upper limit of the content of SiO2 in the present invention is 15%, preferably 12%, and more preferably 10%.

[0030] B2O3 improves the meltability and devitrification resistance of the glass and is advantageous for reducing the transition temperature of the glass. In the present invention, the above effects are obtained by containing 5% or more of B2O3. Preferably, it contains 7% or more of B2O3, and more preferably 9% or more of B2O3. If the content of B2O3 is too much, the chemical stability of the glass, especially the water resistance, becomes low, and the refractive index and light transmittance of the glass decrease. Therefore, the content of B2O3 is 25% or less, preferably 20% or less, and more preferably 16% or less.

[0031] La2O3 is an effective component for improving the refractive index of the glass, and has a remarkable effect on improving the chemical stability and devitrification resistance of the glass. When its content is less than 35%, it becomes difficult to achieve the desired optical constants. Conversely, when the content exceeds 65%, the devitrification tendency of the glass increases and the thermal stability becomes low. Therefore, the content of La2O3 is limited to 35 - 65%, preferably limited to 40 - 60%, and more preferably limited to 42 - 55%.

[0032] Y2O3 can improve the refractive index and devitrification resistance of the glass, and can adjust the Young's modulus of the glass. In the present invention, by containing 4% or more of Y2O3, the above effects can be obtained. When its content exceeds 25%, the chemical stability and weather resistance of the glass will decrease. Therefore, in the present invention, the content of Y2O3 is 4 to 25%, preferably 6 to 22%, more preferably 8 to 20%, and still more preferably 11 to 20%.

[0033] In some embodiments, by controlling the ratio (SiO2 + Y2O3) / B2O3 of the total content of SiO2 and Y2O3, SiO2 + Y2O3, to the content of B2O3 within the range of 0.5 to 5.0, the bubble degree and light transmittance of the glass can be improved. Therefore, preferably, (SiO2 + Y2O3) / B2O3 is 0.5 to 5.0, more preferably 0.7 to 3.0. Further, by controlling (SiO2 + Y2O3) / B2O3 within the range of 1.0 to 2.5, the hardness of the glass can be further optimized. Therefore, (SiO2 + Y2O3) / B2O3 is more preferably 1.0 to 2.5, and even more preferably 1.0 to 2.0.

[0034] Gd2O3 can improve the refractive index and chemical stability of the glass, but when its content exceeds 10%, the devitrification resistance and abrasion degree of the glass will decrease. Therefore, the content of Gd2O3 is 0 to 10%, preferably 0 to 7%, more preferably 0 to 5%.

[0035] In some embodiments, by controlling the total content of La2O3, Y2O3 and Gd2O3, La2O3 + Y2O3 + Gd2O3, within the range of 45 to 75%, it is easy for the glass to obtain the desired refractive index and Abbe number, and the devitrification resistance and weather resistance of the glass are optimized. Therefore, La2O3 + Y2O3 + Gd2O3 is preferably 45 to 75%, more preferably 50 to 75%, still more preferably 55 to 70%, and even more preferably 60 to 70%.

[0036] Yb2O3 is also a component that imparts high refractive index and low dispersion performance to the glass. When its content exceeds 10%, the devitrification resistance performance of the glass decreases. Therefore, the content of Yb2O3 is 0 to 10%, preferably 0 to 5%, more preferably 0 to 3%, and even more preferably, it does not contain Yb2O3.

[0037] ZrO2 can improve the viscosity, hardness, refractive index and chemical stability of the optical glass, and can also reduce the thermal expansion coefficient of the glass. If the content of ZrO2 is too high, the devitrification resistance of the glass decreases, the melting difficulty increases, the melting temperature rises, leading to the generation of inclusions inside the glass and the decrease of light transmittance. Therefore, in the present invention, the content of ZrO2 is 2 to 15%, preferably 3 to 12%, more preferably 4 to 10%.

[0038] In some embodiments, by controlling the ratio Y2O3 / (SiO2 + ZrO2) of the content of Y2O3 to the total content SiO2 + ZrO2 of SiO2 and ZrO2 within the range of 0.3 to 3.5, the abrasion degree of the glass can be optimized and the decrease of glass hardness can be prevented. Therefore, Y2O3 / (SiO2 + ZrO2) is preferably 0.3 to 3.5, more preferably 0.4 to 3.0. Further, by controlling Y2O3 / (SiO2 + ZrO2) within the range of 0.5 to 2.5, the weather resistance and Young's modulus of the glass can be further optimized. Therefore, Y2O3 / (SiO2 + ZrO2) is more preferably 0.5 to 2.5, and even more preferably 0.5 to 2.0.

[0039] Nb2O5 is a high refractive index and high dispersion component, which can improve the refractive index and devitrification resistance of the glass and reduce the thermal expansion coefficient of the glass. In the present invention, the above effects are obtained by containing 3% or more of Nb2O5. Preferably, the lower limit of the content of Nb2O5 is 5%, more preferably 7%. When the content of Nb2O5 exceeds 20%, the thermal stability and weather resistance of the glass decrease, and the light transmittance decreases. Therefore, in the present invention, the upper limit of the content of Nb2O5 is 20%, preferably 15%, more preferably 11%.

[0040] In some embodiments, by controlling the ratio (Y2O3 + Nb2O5) / La2O3 of the total content of Y2O3 and Nb2O5 to the content of La2O3 within the range of 0.2 to 1.0, it is advantageous for improving the hardness and light transmittance of the glass. Therefore, (Y2O3 + Nb2O5) / La2O3 is preferably 0.2 to 1.0, more preferably 0.25 to 0.8. Furthermore, by controlling (Y2O3 + Nb2O5) / La2O3 within the range of 0.3 to 0.7, the Young's modulus and bubble degree of the glass can be further optimized. Therefore, (Y2O3 + Nb2O5) / La2O3 is more preferably 0.3 to 0.7, even more preferably 0.35 to 0.65.

[0041] In some embodiments, by controlling the ratio Nb2O5 / B2O3 of the content of Nb2O5 to the content of B2O3 within the range of 0.2 to 2.5, the chemical stability and light transmittance of the glass can be optimized. Therefore, Nb2O5 / B2O3 is preferably 0.2 to 2.5, more preferably 0.4 to 2.0. Furthermore, by controlling Nb2O5 / B2O3 within the range of 0.5 to 1.8, the bubble degree and thermal expansion coefficient of the glass can be further optimized. Therefore, Nb2O5 / B2O3 is more preferably 0.5 to 1.8, even more preferably 0.6 to 1.5.

[0042] TiO2 can improve the refractive index of glass, but if its content is too high, it will significantly reduce the dispersion coefficient, increase the crystallization tendency, and ultimately cause significant coloring of the glass. Therefore, the content of TiO2 is limited to 0 - 10%, preferably limited to 0 - 8%, and more preferably limited to 0 - 5%.

[0043] In some embodiments, by controlling the ratio TiO2 / (Y2O3 + Nb2O5) of the content of TiO2 to the total content of Y2O3 and Nb2O5 to be 1.0 or less, the crystallization resistance and weather resistance of the glass can be improved. Therefore, TiO2 / (Y2O3 + Nb2O5) is preferably 1.0 or less, and more preferably 0.8 or less. Furthermore, by controlling TiO2 / (Y2O3 + Nb2O5) to be 0.5 or less, the thermal expansion coefficient and hardness of the glass can be further optimized. Therefore, TiO2 / (Y2O3 + Nb2O5) is more preferably 0.5 or less, and even more preferably 0.3 or less.

[0044] Alkaline earth metal oxide RO (RO is one or more of MgO, CaO, SrO, BaO) can adjust the optical constants of the glass and optimize the chemical stability of the glass, but if its content is too high, the devitrification resistance of the glass will decrease. Therefore, the content of RO is limited to 0 - 8%, preferably limited to 0 - 3%, and more preferably limited to 0 - 2%. In some embodiments, more preferably, RO is not contained.

[0045] Alkali metal oxide Rn2O (Rn2O is one or more of Li2O, Na2O, K2O) can lower the transition temperature of the glass, adjust the optical constants and high-temperature viscosity of the glass, and improve the meltability of the glass, but if its content is too high, the devitrification resistance and chemical stability of the glass will decrease. Therefore, in the present invention, the content of Rn2O is 0 - 8%, preferably 0 - 3%, and more preferably 0 - 2%. In some embodiments, more preferably, Rn2O is not contained.

[0046] In some embodiments, by controlling the ratio (RO + Rn2O) / SiO2 of the total content of RO and Rn2O to the content of SiO2 to 1.5 or less, the weather resistance and the degree of veining of the glass can be optimized, and it is easier for the glass to obtain an appropriate Young's modulus. Therefore, (RO + Rn2O) / SiO2 is preferably 1.5 or less, more preferably 1.0 or less, still more preferably 0.8 or less, and even more preferably 0.5 or less.

[0047] WO3 can improve the refractive index and mechanical strength of the glass. However, when the content of WO3 exceeds 5%, the thermal stability of the glass decreases and the devitrification resistance decreases. Therefore, the upper limit of the content of WO3 is 5%, preferably 3%, and more preferably 2%. In some embodiments, more preferably, WO3 is not contained.

[0048] ZnO can adjust the refractive index and dispersion of the glass and lower the high-temperature viscosity and transition temperature of the glass. If the content of ZnO is too high, glass forming becomes difficult and the crystallization resistance performance becomes low. Therefore, the content of ZnO is 0 to 10%, preferably 0 to 5%, and more preferably 0 to 2%. In some embodiments, more preferably, ZnO is not contained.

[0049] In some embodiments, by controlling the ratio ZnO / Y2O3 of the content of ZnO to the content of Y2O3 to 1.0 or less, the bubble degree and chemical stability of the glass can be improved, the thermal expansion coefficient of the glass can be decreased, and the abrasion degree of the glass can be optimized. Therefore, ZnO / Y2O3 is preferably 1.0 or less, more preferably 0.8 or less, still more preferably 0.5 or less, and even more preferably 0.2 or less.

[0050] Ta2O5 has the effect of improving the refractive index and the devitrification resistance of the glass. However, if its content is too high, the thermal stability of the glass will decrease, the density will increase, and it will be difficult to control the optical constants within the desired range. On the other hand, Ta2O5 is very expensive compared to other components. Therefore, from the viewpoints of practicality and cost, its usage amount should be reduced as much as possible. Accordingly, in the present invention, the content of Ta2O5 is limited to 0 to 5%, preferably limited to 0 to 3%, and more preferably limited to 0 to 1%. In some embodiments, more preferably, Ta2O5 is not contained.

[0051] In some embodiments, by controlling the ratio (Ta2O5 + Gd2O3) / Nb2O5 of the total content of Ta2O5 and Gd2O3 (Ta2O5 + Gd2O3) to the content of Nb2O5 to be 2.0 or less, the chemical stability of the glass can be improved and the thermal expansion coefficient of the glass can be reduced. Therefore, (Ta2O5 + Gd2O3) / Nb2O5 is preferably 2.0 or less, and more preferably 1.5 or less. (Ta2O5 + Gd2O3) / Nb2O5 is more preferably 1.0 or less, which is advantageous for optimizing the density and Young's modulus of the glass. Therefore, (Ta2O5 + Gd2O3) / Nb2O5 is more preferably 1.0 or less, and even more preferably 0.8 or less.

[0052] Al2O3 can improve the chemical stability of the glass. However, when its content exceeds 8%, the meltability and light transmittance of the glass will decrease. Therefore, in the present invention, the content of Al2O3 is 0 to 8%, preferably 0 to 4%, and more preferably 0 to 2%. In some embodiments, more preferably, Al2O3 is not contained.

[0053] GeO2 has the effect of improving the refractive index and devitrification resistance. However, if its content is too high, the chemical stability of the glass will decrease. On the other hand, GeO2 is very expensive compared to other components. Therefore, from the perspectives of practicality and cost, its usage amount should be reduced as much as possible. Accordingly, in the present invention, the content of GeO2 is limited to 0 to 5%, preferably limited to 0 to 3%, more preferably limited to 0 to 1%, and even more preferably, it does not contain GeO2.

[0054] In the present invention, by containing one or more components of Sb2O3, SnO, SnO2, and CeO2 in the range of 0 to 2% as fining agents, the fining effect of the glass can be improved, and the bubble degree of the glass can be improved. The content of the fining agent is preferably 0 to 1%, more preferably 0 to 0.5%. The optical glass of the present invention has a reasonable design of the type and content of the components and is excellent in bubble degree. Therefore, in some embodiments, more preferably, it does not contain a fining agent. When the content of Sb2O3 exceeds 2%, the fining performance of the glass tends to decrease, and due to its strong oxidizing action, the corrosion of the platinum or platinum alloy dish for melting the glass and the deterioration of the molding die are promoted. Therefore, in the present invention, the content of Sb2O3 is preferably 0 to 2%, more preferably 0 to 1%, further preferably 0 to 0.5%, and even more preferably, it does not contain Sb2O3. SnO and SnO2 may be used as fining agents, but when their content exceeds 2%, the coloring tendency of the glass increases, or when the glass is heated, softened, and remolded by press molding or the like, Sn tends to become a starting point for crystal nucleation and devitrification occurs. Therefore, the content of SnO2 in the present invention is preferably 0 to 2%, more preferably 0 to 1%, further preferably 0 to 0.5%, and even more preferably, it does not contain SnO2. The content of SnO is preferably 0 to 2%, more preferably 0 to 1%, further preferably 0 to 0.5%, and even more preferably, it does not contain SnO. CeO2 has the same action and content ratio as SnO2, and its content is preferably 0 to 2%, more preferably 0 to 1%, further preferably 0 to 0.5%, and even more preferably, it does not contain CeO2.

[0055] <Components that should not be contained> In the glass of the present invention, even when a small amount of oxides of transition metals such as V, Cr, Mn, Fe, Co, Ni, Cu, Ag, and Mo are contained alone or in combination, the glass is colored and absorbs at specific wavelengths in the visible light region, which has the property of weakening the visible light transmittance improvement effect of the present invention. Therefore, in the case of optical glass where the transmittance of wavelengths in the visible light region is particularly required, preferably, the oxides of the transition metals are not substantially contained.

[0056] Oxides of Th, Cd, Tl, Os, Be, and Se tend to be restricted from use as harmful chemical substances in recent years. In addition to the glass manufacturing process, environmental protection measures are required in the processing process and the treatment after productization. Therefore, when emphasizing the impact on the environment, preferably, oxides of Th, Cd, Tl, Os, Be, and Se are not substantially contained except for inevitable contamination. As a result, the optical glass will not substantially contain substances that pollute the environment. Therefore, the optical glass of the present invention can be manufactured, processed, and discarded without taking special environmental countermeasures.

[0057] Preferably, the optical glass of the present invention does not contain As2O3 and PbO because it is environmentally friendly.

[0058] "Not containing" and "0%" described in the present text mean that the compound, molecule, element, etc. are not intentionally added to the optical glass of the present invention as raw materials. However, as raw materials and / or equipment for manufacturing the optical glass, there may be some impurities or components that are not intentionally added and are contained in trace amounts or in small amounts in the final optical glass. Such situations are also within the scope of the claims of the present invention.

[0059] Next, the performance of the optical glass of the present invention will be described.

[0060] <Refractive Index and Abbe Number> The refractive index (n d ) and Abbe number (ν d ) of the optical glass are measured according to the method specified in 'GB / T 7962.1 - 2010'.

[0061] In some embodiments, the lower limit of the refractive index (n d ) of the optical glass of the present invention is 1.87, preferably 1.88, and more preferably 1.89.

[0062] In some embodiments, the upper limit of the refractive index (n d ) of the optical glass of the present invention is 1.94, preferably 1.92, and more preferably 1.91.

[0063] In some embodiments, the lower limit of the Abbe number (ν d ) of the optical glass of the present invention is 33, preferably 35, and more preferably 36.

[0064] In some embodiments, the upper limit of the Abbe number (ν d ) of the optical glass of the present invention is 41, preferably 40, and more preferably 39.

[0065] <Coefficient of thermal expansion> For the coefficient of thermal expansion (α 20 / 120℃ ) of the optical glass, data at 20 - 120 °C are measured according to the method specified in 'GB / T 7962.16 - 2010'.

[0066] In some embodiments, the coefficient of thermal expansion (α 20 / 120℃ ) of the optical glass of the present invention is 95×10 -7 / K or less, preferably 90×10 -7 / K or less, and more preferably 80×10 -7 / K or less.

[0067] <Stability against the action of water> The stability against the action of water (D W ) (powder method) of the optical glass is measured according to the method specified in 'GB / T 17129'.

[0068] In some embodiments, the stability against the action of water (D WThere are two or more types, preferably one type.

[0069] <Degree of coloring> The short-wavelength spectral transmittance characteristics of the glass of the present invention are represented by the degree of coloring (λ 70 and λ5). λ 70 means the wavelength at which the glass transmittance reaches 70%. The measurement of λ 70 is to measure the spectral transmittance in the wavelength range from 280 nm to 700 nm using a glass with a thickness of 10 ± 0.1 mm having two opposing planes that are parallel to each other and optically polished, and to indicate the wavelength at which the transmittance becomes 70%. The spectral transmittance or transmittance is the amount represented by I in of light perpendicularly incident on the above surface of the glass and transmitted through the glass to emit light of intensity I out from one plane, and is the transmittance including the surface reflection loss at the above surface of the glass. The higher the refractive index of the glass, the greater the surface reflection loss. Therefore, in the glass with a high refractive index, the small value of λ out / I in means that the coloring of the glass itself is extremely small and the light transmittance is high. 70 In some embodiments, λ

[0070] of the optical glass of the present invention is 410 nm or less, preferably 400 nm or less, and more preferably 395 nm or less. 70 In some embodiments, λ5 of the optical glass of the present invention is 370 nm or less, preferably 360 nm or less, and more preferably 355 nm or less.

[0071] <Weather resistance>

[0072] The method for measuring the weather resistance (CR) of the optical glass is as follows. Place the sample in a test chamber with a relative humidity of 90% and a saturated water vapor environment, circulate alternately every 1 h at 40 - 50 °C, and perform 15 cycles of circulation. Based on the amount of change in turbidity before and after leaving the sample, classify the weather resistance type, and show the classification status of the weather resistance in Table 1.

[0073]

Table 1

[0074] In some embodiments, the weather resistance (CR) of the optical glass of the present invention is two or more, preferably one kind.

[0075] <Knoop hardness> The Knoop hardness (H K ) of the optical glass is measured according to the measurement method specified in "GB / T 7962.18 - 2010".

[0076] In some embodiments, the lower limit of the Knoop hardness (H K ) of the optical glass of the present invention is 670×10 7 Pa or more, preferably 680×10 7 Pa or more, more preferably 690×10 7 Pa or more.

[0077] <Young's modulus> The Young's modulus (E) is calculated by measuring the longitudinal wave velocity and the transverse wave velocity with ultrasonic waves and using the following formula.

[0078]

Equation

[0079] In some embodiments, the lower limit of the Young's modulus (E) of the optical glass of the present invention is 10000×10 7 Pa, preferably 11000×10 7It is Pa, more preferably 11500×10 7 Pa.

[0080] In some embodiments, the upper limit of the Young's modulus (E) of the optical glass of the present invention is 14000×10 7 Pa, preferably 13500×10 7 Pa, more preferably 13000×10 7 Pa.

[0081] <Bubble degree> The bubble degree of the optical glass is measured according to the method specified in 'GB / T 7962.8-2010'.

[0082] In some embodiments, the bubble degree of the optical glass of the present invention is A grade or above, preferably A0 grade or above, more preferably A 00 grade.

[0083] [Manufacturing method of optical glass] The manufacturing method of the optical glass of the present invention is as follows. The glass of the present invention is manufactured from conventional raw materials (including, but not limited to, oxides, hydroxides, composite salts (such as carbonates, nitrates, sulfates, etc.), boric acid, etc.) and processes. After preparing the raw materials by conventional methods, the prepared furnace materials are put into a melting furnace (such as a platinum or platinum alloy crucible) at 1200~1450°C for melting, and after clarification and homogenization, a homogeneous molten glass without bubbles and containing no undissolved substances is obtained, and this molten glass is cast and annealed in a mold to form. Those skilled in the art can appropriately select raw materials, process methods and process parameters according to actual needs.

[0084] [Glass molded body and optical element] To manufacture a glass molded body from the manufactured optical glass, for example, direct gob forming, means such as polishing, or press forming means such as hot press forming can be used. That is, the molten optical glass is directly precision gob formed to manufacture a glass precision molded body, or the glass molded body is manufactured by machining such as grinding and polishing, or a preform for press forming is manufactured from the optical glass, and after the preform is reheat press formed, it is polished to manufacture the glass molded body. Note that the means for manufacturing the glass molded body is not limited to the above means.

[0085] As described above, the optical glass of the present invention is useful for various optical elements and optical designs. Particularly preferably, a preform is formed from the optical glass of the present invention, and reheat press forming, precision press forming, etc. are performed on the preform to manufacture optical elements such as lenses and prisms.

[0086] Both the glass molded body and the optical element of the present invention are formed of the above-described optical glass of the present invention. The glass molded body of the present invention has excellent properties of the optical glass, and the optical element of the present invention has excellent properties of the optical glass, and can provide various optical elements such as lenses and prisms with high optical value.

[0087] Examples of the lens include various lenses such as a concave meniscus lens, a convex meniscus lens, a biconvex lens, a biconcave lens, a plano-convex lens, and a plano-concave lens in which the lens surface is spherical or aspherical.

[0088] [Optical equipment] Using the optical element formed of the optical glass of the present invention, for example, optical equipment such as camera equipment, imaging equipment, projection equipment, display equipment, in-vehicle equipment, and monitoring equipment can be manufactured.

[0089] (Examples) <Examples of optical glass> To more clearly interpret and explain the technical means of the present invention, the following non-limiting examples are provided.

[0090] In this example, optical glasses having the compositions shown in Tables 2 to 4 are obtained by the method for manufacturing the above optical glass. Further, the properties of each glass are measured by the measurement method described in the present invention, and the measurement results are shown in Tables 2 to 4.

[0091] [Table 2]

[0092] [Table 3]

[0093] [Table 4]

[0094] <Examples of Glass Moldings> The glasses obtained in Examples 1 to 24# of the optical glass are processed by means such as polishing, or press molding means such as reheat pressing and precision press molding to produce various lenses such as concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, plano-concave lenses, and moldings such as prisms.

[0095] <Examples of Optical Elements> These moldings obtained in the examples of the glass molding are annealed to reduce the internal stress of the glass and finely adjust the refractive index, thereby achieving desired values for optical properties such as the refractive index.

[0096] Next, each molding is ground and polished to produce various lenses such as concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, plano-concave lenses, and prisms. An antireflection film may be applied to the surface of the obtained optical element.

[0097] <Examples of Optical Instruments> Optical design is performed on the optical element manufactured in the above-described embodiment of the optical element, and the optical component or optical assembly formed using one or more optical elements can be used, for example, in imaging devices, sensors, microscopes, pharmaceutical technology, digital projection, communication, optical communication technology / information transmission, optical / lighting in the automotive field, photolithography technology, excimer lasers, wafers, computer chips, and integrated circuits and electronic devices including such circuits and chips.

Claims

1. As components, in weight percentage, 1 to 15% of SiO ２ , 5 to 25% of B ２ O ３ , 2 to 15% of ZrO ２ , 3 to 20% of Nb ２ O ５ , and 45 to 75% of La ２ O ３ + Y ２ O ３ + Gd ２ O ３ containing An optical glass, characterized in that...

2. As components, in weight percentage, 0 to 10% of TiO ２ and / or 0 to 5% of Ta ２ O ５ and / or 0 to 8% of RO, and / or 0 to 8% of Rn ２ O, and / or 0 to 5% of WO ３ and / or 0 to 10% of ZnO, and / or 0 to 8% of Al ２ O ３ and / or 0 to 10% of Yb ２ O ３ and / or 0 to 5% of GeO ２ and further contains 0 to 2% of a clarifying agent, wherein the RO is one or more of MgO, CaO, SrO, BaO, and Rn ２ O is one or more of Li ２ O, Na ２ O, K ２ O, and the clarifying agent is one or more of Sb ２ O ３ , SnO, SnO ２ , CeO ２ among them. The optical glass according to Claim 1, characterized in that...

3. As components, by weight percentage, 1 to 15% of SiO ２ , 5 to 25% of B ２ O ３ , 2 to 15% of ZrO ２ , 3 to 20% of Nb ２ O ５ , 45 to 75% of La ２ O ３ + Y ２ O ３ + Gd ２ O ３ , 0 to 10% of TiO ２ , 0 to 5% of Ta ２ O ５ , 0 to 8% of RO, 0 to 8% of Rn ２ O, 0 to 5% of WO ３ , 0 to 10% of ZnO, 0 to 8% of Al ２ O ３ , 0 to 10% of Yb ２ O ３ , 0 to 5% of GeO ２ , and contains 0 to 2% of a clarifying agent, wherein the RO is one or more of MgO, CaO, SrO, BaO, and Rn ２ O is one or more of Li ２ O, Na ２ O, K ２ O, and the clarifying agent is one or more of Sb ２ O ３ , SnO, SnO ２ , CeO ２ is one or more of them. An optical glass, characterized in that...

4. As components, by weight percentage, (SiO ２ +Y ２ O ３ ) / B ２ O ３ is 0.5 to 5.0, preferably, (SiO ２ +Y ２ O ３ ) / B ２ O ３ is 0.7 to 3.0, more preferably, (SiO ２ +Y ２ O ３ ) / B ２ O ３ is 1.0 to 2.5, even more preferably, (SiO ２ +Y ２ O ３ ) / B ２ O ３ is 1.0 to 2.0, The optical glass according to any one of Claims 1 to 3, characterized in that...

5. As a component, in terms of weight percentage, Y ２ O ３ / (SiO ２ + ZrO ２ ) is 0.3 to 3.5, preferably, Y ２ O ３ / (SiO ２ + ZrO ２ ) is 0.4 to 3.0, more preferably, Y ２ O ３ / (SiO ２ + ZrO ２ ) is 0.5 to 2.5, even more preferably, Y ２ O ３ / (SiO ２ + ZrO ２ ) is 0.5 to 2.0, The optical glass according to any one of Claims 1 to 3, characterized in that...

6. As a component, in weight percentage, (Y ２ O ３ + Nb ２ O ５ ) / La ２ O ３ is 0.2 to 1.0, preferably, (Y ２ O ３ + Nb ２ O ５ ) / La ２ O ３ is 0.25 to 0.8, more preferably, (Y ２ O ３ + Nb ２ O ５ ) / La ２ O ３ is 0.3 to 0.7, even more preferably, (Y ２ O ３ + Nb ２ O ５ ) / La ２ O ３ is 0.35 to 0.65, The optical glass according to any one of Claims 1 to 3, characterized in that...

7. As a component, by weight percentage, Nb ２ O ５ / B ２ O ３ is 0.2 to 2.5, preferably, Nb ２ O ５ / B ２ O ３ is 0.4 to 2.0, more preferably, Nb ２ O ５ / B ２ O ３ is 0.5 to 1.8, even more preferably, Nb ２ O ５ / B ２ O ３ is 0.6 to 1.5, The optical glass according to any one of Claims 1 to 3, characterized in that...

8. As a component, in terms of weight percentage, TiO ２ / (Y ２ O ３ + Nb ２ O ５ ) is 1.0 or less, preferably, TiO ２ / (Y ２ O ３ + Nb ２ O ５ ) is 0.8 or less, more preferably, TiO ２ / (Y ２ O ３ + Nb ２ O ５ ) is 0.5 or less, even more preferably, TiO ２ / (Y ２ O ３ + Nb ２ O ５ ) is 0.3 or less. The optical glass according to any one of Claims 1 to 3, characterized in that...

9. As a component, in weight percentage, (RO + Rn ２ O) / SiO ２ is 1.5 or less, preferably, (RO + Rn ２ O) / SiO ２ is 1.0 or less, more preferably, (RO + Rn ２ O) / SiO ２ is 0.8 or less, still more preferably, (RO + Rn ２ O) / SiO ２ is 0.5 or less, wherein RO is one or more of MgO, CaO, SrO, and BaO, and Rn ２ O is one or more of Li ２ O, Na ２ O, and K ２ O), The optical glass according to any one of Claims 1 to 3, characterized in that...

10. As a component, ZnO / Y in weight percentage ２ O ３ is 1.0 or less, preferably, ZnO / Y ２ O ３ is 0.8 or less, more preferably, ZnO / Y ２ O ３ is 0.5 or less, even more preferably, ZnO / Y ２ O ３ is 0.2 or less The optical glass according to any one of Claims 1 to 3, characterized in that...

11. As a component, in terms of weight percentage, (Ta ２ O ５ + Gd ２ O ３ ) / Nb ２ O ５ is 2.0 or less, preferably, (Ta ２ O ５ + Gd ２ O ３ ) / Nb ２ O ５ is 1.5 or less, more preferably, (Ta ２ O ５ + Gd ２ O ３ ) / Nb ２ O ５ is 1.0 or less, even more preferably, (Ta ２ O ５ + Gd ２ O ３ ) / Nb ２ O ５ is 0.8 or less, The optical glass according to any one of Claims 1 to 3, characterized in that...

12. As components, by weight percentage, 2 to 12% of SiO ２ , preferably, 4 to 10% of SiO ２ , and / or 7 to 20% of B ２ O ３ , preferably, 9 to 16% of B ２ O ３ , and / or 50 to 75% of La ２ O ３ +Y ２ O ３ +Gd ２ O ３ , preferably, 55 to 70% of La ２ O ３ +Y ２ O ３ +Gd ２ O ３ , more preferably, 60 to 70% of La ２ O ３ +Y ２ O ３ +Gd ２ O ３ , and / or 3 to 12% of ZrO ２ , preferably, 4 to 10% of ZrO ２ , and / or 5 to 15% of Nb ２ O ５ , preferably, 7 to 11% of Nb ２ O ５ , and / or 0 to 3% of Ta ２ O ５ , preferably, 0 to 1% of Ta ２ O ５ , and / or 0 to 8% of TiO ２ , preferably, 0 to 5% of TiO ２ , and / or 0 to 3% of RO, preferably, 0 to 2% of RO, and / or 0 to 3% of Rn ２ O, preferably, 0 to 2% of Rn ２ O, and / or 0 to 3% of WO ３ , preferably, 0 to 2% of WO ３ , and / or 0 to 5% of ZnO, preferably, 0 to 2% of ZnO, and / or 0 to 4% of Al ２ O ３ , preferably, 0 to 2% of Al ２ O ３ , and / or 0 to 5% of Yb ２ O ３ 、 preferably, 0 to 3% of Yb ２ O ３ 、 and / or 0 to 3% of GeO ２ 、 preferably, 0 to 1% of GeO ２ 、 and / or 0 to 1% of a clarifying agent, preferably, 0 to 0.5% of a clarifying agent, and the RO is one or more of MgO, CaO, SrO, BaO, and Rn ２ O is one or more of Li ２ O, Na ２ O, K ２ O, and the clarifying agent is one or more of Sb ２ O ３ 、 SnO, SnO ２ 、 CeO ２ 、 etc. The optical glass according to any one of Claims 1 to 3, characterized in that...

13. As components, La in a weight percentage of 35 to 65%, ２ O ３ preferably, La in a weight percentage of 40 to 60%, ２ O ３ more preferably, La in a weight percentage of 42 to 55%, ２ O ３ and / or Y in a weight percentage of 4 to 25%, ２ O ３ preferably, Y in a weight percentage of 6 to 22%, ２ O ３ more preferably, Y in a weight percentage of 8 to 20%, ２ O ３ even more preferably, Y in a weight percentage of 11 to 20%, ２ O ３ and / or Gd in a weight percentage of 0 to 10%, ２ O ３ preferably, Gd in a weight percentage of 0 to 7%, ２ O ３ more preferably, Gd in a weight percentage of 0 to 5%, ２ O ３ containing The optical glass according to any one of Claims 1 to 3, characterized in that...

14. As components, WO ３ , and / or Ta ２ O ５ , and / or RO, and / or Rn ２ O, and / or ZnO, and / or Al ２ O ３ , and / or GeO ２ is not contained, and the RO is one or more of MgO, CaO, SrO, BaO, and Rn ２ O is one or more of Li ２ O, Na ２ O, K ２ O The optical glass according to any one of Claims 1 to 3, characterized in that...

15. Refractive index n ｄ is from 1.87 to 1.94, preferably from 1.88 to 1.92, more preferably from 1.89 to 1.91, and the Abbe number ν ｄ is from 33 to 41, preferably from 35 to 40, more preferably from 36 to 39. The optical glass according to any one of Claims 1 to 3, characterized in that...

16. Thermal expansion coefficient α ２０／１２０℃ is 95×10 －７ / K or less, preferably 90×10 －７ / K or less, more preferably 80×10 －７ / K or less, and / or water resistance stability D Ｗ is two or more, preferably one, and / or λ ７０ is 410 nm or less, preferably 400 nm or less, more preferably 395 nm or less, and / or λ ５ is 370 nm or less, preferably 360 nm or less, more preferably 355 nm, and / or weather resistance CR is two or more, preferably one, and / or Knoop hardness H Ｋ is 670×10 ７ Pa or more, preferably 680×10 ７ Pa or more, more preferably 690×10 ７ Pa or more, and / or Young's modulus E is 10000×10 ７ Pa to 14000×10 ７ Pa, preferably 11000×10 ７ Pa to 13500×10 ７ Pa, more preferably 11500×10 ７ Pa to 13000×10 ７ Pa, and / or the porosity is Class A or higher, preferably Class A ０ Class A or higher, more preferably Class A ００ Class., The optical glass according to any one of Claims 1 to 3, characterized in that...

17. A glass formed body, manufactured from the optical glass according to any one of Claims 1 to 16, characterized in that...

18. An optical element, manufactured from the optical glass according to any one of Claims 1 to 16, or the glass formed body according to Claim 17, characterized in that...

19. An optical device, comprising the optical glass according to any one of Claims 1 to 16, and / or the optical element according to Claim 18, characterized in that...

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