Optical glass, glass preform, optical element, and optical device

Abstract

The present invention provides an optical glass, and when its composition is expressed in weight percentage, it contains SiO 2 : 2% to 20%, B 2 O 3 : 3% to 20%, La 2 O 3 : 35% to 60%, Y 2 O 3 : 5% to 30%, ZrO 2 : 2% to 15%, Nb 2 O 5 : 1% to 15%, and Ta 2 O 5 : 0 to 15%. By reasonable composition design, the present invention can obtain an optical glass with excellent chemical stability at low raw material cost.

Description

Technical Field

[0001] The present invention relates to optical glass, and particularly to optical glass having a refractive index of 1.86 to 1.92 and an Abbe number of 36 to 44, and a glass preform, an optical element, and an optical device manufactured thereby.

Background Art

[0002] In recent years, due to the progress of digitalization and high definition of optical devices, the requirements for optical glass used in optical devices have been increasing. Optical glass having a refractive index of 1.86 to 1.92 and an Abbe number of 36 to 44 has a high refractive index, so it is easy to achieve miniaturization, ultra-thinning, and wide-angleization, and has a wide range of application scenarios. In order to apply optical glass to various optical devices, it is necessary to process or clean the optical glass. If the chemical stability of the optical glass is poor, defects are likely to occur in the glass during processing or cleaning, and the yield of the optical glass decreases. In the prior art, all optical glasses having a refractive index of 1.86 to 1.92 and an Abbe number of 36 to 44 contain a large amount of Ta 2 O 5 For example, the optical glass disclosed in CN101386469A having a refractive index of 1.85 to 1.90 and an Abbe number of 35 to 45 contains more than 19% and less than 27% of Ta 2 O 5 Ta 2 O 5 is a rare metal component, and a high content of Ta 2 O 5 is disadvantageous for cost control of optical glass. In various optical devices such as imaging devices such as digital cameras and digital video cameras, and image reproduction (projection) devices such as projectors and projection TVs, in order to improve the yield and reduce the cost, the use of optical glass having excellent chemical stability and low raw material cost is desired.

Summary of the Invention

Problems to be Solved by the Invention

[0003] The problem to be solved by the present invention is to provide an optical glass with low raw material costs and excellent chemical stability.

Means for Solving the Problem

[0004] The means adopted by the present invention to solve the problem are as follows. An optical glass, when the composition is expressed in weight percentage, contains SiO 2 : 2% to 20%, B 2 O 3 : 3% to 20%, La 2 O 3 : 35% to 60%, Y 2 O 3 : 5% to 30%, ZrO 2 : 2% to 15%, Nb 2 O 5 : 1% to 15%, and Ta 2 O 5 : 0 to 15%.

[0005] Furthermore, when the composition of the optical glass is expressed in weight percentage, it further contains Gd 2 O 3 : 0 to 8%, and / or TiO 2 : 0 to 5%, and / or RO: 0 to 8%, and / or Rn 2 O: 0 to 8%, and / or WO 3 : 0 to 5%, and / or ZnO: 0 to 8%, and / or Al 2 O 3 : 0 to 8%, and / or Yb 2 O 3 : 0 to 8%, and / or GeO 2 : 0 to 5%, and / or fining agent: 0 to 2%. The 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 fining agent is one or more of Sb 2 O 3 , SnO, SnO 2 2 CeO : 0 to 8%, and / or GeO

[0006] An optical glass, when the composition is expressed in weight percentages, contains SiO 2 : 2% to 20%, B 2 O 3 : 3% to 20%, La 2 O 3 : 35% to 60%, Y 2 O 3 : 5% to 30%, ZrO 2 : 2% to 15%, Nb 2 O 5 : 1% to 15%, Ta 2 O 5 : 0 to 15%, Gd 2 O 3 : 0 to 8%, TiO 2 : 0 to 5%, RO: 0 to 8%, Rn 2 O: 0 to 8%, WO 3 : 0 to 5%, ZnO: 0 to 8%, Al 2 O 3 : 0 to 8%, Yb 2 O 3 : 0 to 8%, GeO 2 : 0 to 5%, and a fining agent: 0 to 2%. The 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, K 2 O. The fining agent is one or more of Sb 2 O 3 , SnO, SnO 2 , CeO 2 .

[0007] Furthermore, when the composition of the optical glass is expressed in weight percentages, La 2 O 3 +Y 2 O 3 +Gd 2 O 3 is 45% to 75%, preferably, La 2 O 3 +Y 2 O 3 +Gd 2 O 3 is 50% to 75%, more preferably, La2 O 3 +Y 2 O 3 +Gd 2 O 3 is 55% - 70%, and more preferably, La 2 O 3 +Y 2 O 3 +Gd 2 O 3 is 60% - 70%.

[0008] Furthermore, when the composition of the optical glass is expressed in weight percentage, Y 2 O 3 / B 2 O 3 is 0.5 - 5.0, preferably, Y 2 O 3 / B 2 O 3 is 0.6 - 3.0, more preferably, Y 2 O 3 / B 2 O 3 is 0.7 - 2.5, and more preferably, Y 2 O 3 / B 2 O 3 is 0.8 - 2.0.

[0009] Furthermore, when the composition of the optical glass is expressed in weight percentage, Gd 2 O 3 / (SiO 2 +B 2 O 3 is 1.0 or less, preferably, Gd 2 O 3 / (SiO 2 +B 2 O 3 is 0.8 or less, more preferably, Gd 2 O 3 / (SiO 2 +B 2 O 3 is 0.5 or less, and more preferably, Gd 2 O 3 / (SiO 2 +B 2 O 3) is 0.3 or less.

[0010] Furthermore, when the composition of the optical glass is expressed in weight percentages, (La 2 O 3 +Y 2 O 3 ) / ZrO 2 is 4.0 or more, preferably, (La 2 O 3 +Y 2 O 3 ) / ZrO 2 is 5.0 to 20.0, more preferably, (La 2 O 3 +Y 2 O 3 ) / ZrO 2 is 6.0 to 13.0, still more preferably, (La 2 O 3 +Y 2 O 3 ) / ZrO 2 is 7.0 to 11.0.

[0011] Furthermore, when the composition of the optical glass is expressed in weight percentages, Y 2 O 3 / (Ta 2 O 5 +ZnO) is 0.5 to 8.0, preferably, Y 2 O 3 / (Ta 2 O 5 +ZnO) is 0.7 to 5.0, more preferably, Y 2 O 3 / (Ta 2 O 5 +ZnO) is 0.8 to 4.0, still more preferably, Y 2 O 3 / (Ta 2 O 5 +ZnO) is 1.0 to 3.0.

[0012] Furthermore, when the composition of the optical glass is expressed in weight percentages, La 2 O 3 / Nb 2 O 5 is 3.0 or more, preferably, La2 O 3 / Nb 2 O 5 is 4.0 to 30.0, more preferably, La 2 O 3 / Nb 2 O 5 is 5.0 to 20.0, even more preferably, La 2 O 3 / Nb 2 O 5 is 6.0 to 12.0.

[0013] Furthermore, when the composition of the optical glass is expressed as a weight percentage, (Ta 2 O 5 +Gd 2 O 3 ) / Nb 2 O 5 is 0.3 to 8.0, preferably, (Ta 2 O 5 +Gd 2 O 3 ) / Nb 2 O 5 is 0.5 to 6.0, more preferably, (Ta 2 O 5 +Gd 2 O 3 ) / Nb 2 O 5 is 0.6 to 5.0, even more preferably, (Ta 2 O 5 +Gd 2 O 3 ) / Nb 2 O 5 is 0.8 to 3.0.

[0014] Furthermore, when the composition of the optical glass is expressed as a weight percentage, (TiO 2 +WO 3 ) / Y 2 O 3 is 1.0 or less, preferably, (TiO 2 +WO 3 ) / Y 2 O 3 is 0.8 or less, more preferably, (TiO 2 +WO 3 ) / Y2 O 3 is 0.5 or less, more preferably, (TiO 2 +WO 3 ) / Y 2 O 3 is 0.1 or less.

[0015] Furthermore, when the composition of the optical glass is expressed in weight percentage, (Gd 2 O 3 +ZnO) / Y 2 O 3 is 1.0 or less, preferably, (Gd 2 O 3 +ZnO) / Y 2 O 3 is 0.8 or less, more preferably, (Gd 2 O 3 +ZnO) / Y 2 O 3 is 0.5 or less, more preferably, (Gd 2 O 3 +ZnO) / Y 2 O 3 is 0.3 or less.

[0016] Furthermore, when the composition of the optical glass is expressed in weight percentage, SiO 2 : 3% - 15%, preferably, SiO 2 : 4% - 10%, and / or, B 2 O 3 : 5% - 15%, preferably, B 2 O 3 : 7% - 13%, and / or, La 2 O 3 : 38% - 60%, preferably, La 2 O 3 : 41% - 55%, and / or, Y 2 O 3 : 7% - 24%, preferably, Y 2 O 3 : 8% - 22%, more preferably, Y 2 O 3 : 11% - 22%, and / or, ZrO 2 : 3% - 13%, preferably, ZrO 2 : 4% - 10%, and / or, Nb2 O 5 : 2% to 10%, preferably, Nb 2 O 5 : 3% to 8%, and / or, Ta 2 O 5 : 2% to 12%, preferably, Ta 2 O 5 : 5% to 10%, and / or, Gd 2 O 3 : 0 to 5%, preferably, Gd 2 O 3 : 0 to 3%, and / or, TiO 2 : 0 to 3%, preferably, TiO 2 : 0 to 2%, and / or, RO: 0 to 3%, preferably, RO: 0 to 2%, and / or, Rn 2 O: 0 to 3%, preferably, Rn 2 O: 0 to 2%, and / or, WO 3 : 0 to 3%, preferably, WO 3 : 0 to 2%, and / or, ZnO: 0 to 4%, preferably, ZnO: 0 to 2%, and / or, Al 2 O 3 : 0 to 4%, preferably, Al 2 O 3 : 0 to 2%, and / or, Yb 2 O 3 : 0 to 5%, preferably, Yb 2 O 3 : 0 to 3%, and / or GeO 2 : 0 to 3%, preferably, GeO 2 : 0 to 1%, and / or fining agent: 0 to 1%, preferably, fining agent: 0 to 0.5%, and the RO is one or more of MgO, CaO, SrO, BaO, and Rn 2 O is Li 2 O, Na 2 O, K 2 O, and is one or more of them, and the fining agent is Sb 2 O 3 、SnO, SnO 2 、CeO 2 and is one or more of them.

[0017] Further, the optical glass has a composition of WO 3does not contain, and / or TiO 2 does not contain, and / or does not contain RO, and / or Rn 2 does not contain O, and / or does not contain ZnO, and / or Al 2 O 3 does not contain, and / or GeO 2 does not contain, wherein the RO is one or more of MgO, CaO, SrO, and BaO, and Rn 2 O is Li 2 O, Na 2 O, K 2 O is one or more of them.

[0018] Furthermore, when the composition of the optical glass is expressed in weight percentage, SiO 2 , B 2 O 3 , La 2 O 3 , Y 2 O 3 , ZrO 2 , Nb 2 O 5 , Ta 2 O 5 The total content is 85% or more. Preferably, SiO 2 , B 2 O 3 , La 2 O 3 , Y 2 O 3 , ZrO 2 , Nb 2 O 5 , Ta 2 O 5 The total content is 88% or more. More preferably, SiO 2 , B 2 O 3 , La 2 O 3 , Y 2 O 3 , ZrO 2 , Nb 2 O 5 , Ta 2 O 5 The total content is 90% or more. Even more preferably, SiO 2 , B 2 O 3, La 2 O 3 , Y 2 O 3 , ZrO 2 , Nb 2 O 5 , Ta 2 O 5 The total content thereof is 95% or more.

[0019] Furthermore, the refractive index n of the optical glass d is 1.86 to 1.92, preferably 1.87 to 1.91, more preferably 1.88 to 1.90, and the Abbe number ν d is 36 to 44, preferably 38 to 43, more preferably 39 to 42.

[0020] Furthermore, the density ρ of the optical glass is 5.20 g / cm 3 or less, preferably 5.15 g / cm 3 or less, more preferably 5.10 g / cm 3 or less, and / or the coefficient of thermal expansion α 20 / 120℃ is 85×10 -7 / K or less, preferably 80×10 -7 / K or less, more preferably 75×10 -7 / K or less, and / or the stability D against water action W is class 2 or higher, preferably class 1, and / or λ 70 is 400 nm or less, preferably λ 70 is 390 nm or less, more preferably λ 70 is 385 nm or less, and / or λ 5 is 340 nm or less, preferably λ 5 is 330 nm or less, more preferably λ 5 is 325 nm or less, and / or the weather resistance CR is class 2 or higher, preferably class 1, and / or the Vickers hardness H K is 690×10 7 Pa or more, preferably 700×10 7 Pa or more, more preferably 710×10 7It is Pa or more, and / or the Young's modulus E is 10500×10 7 Pa to 14500×10 7 Pa, preferably 11000×10 7 Pa to 14000×10 7 Pa, more preferably 11500×10 7 Pa to 13500×10 7 Pa, and / or the bubble degree is level A or more, preferably level A 0 or more, more preferably level A 00 or more.

[0021] A glass preform, which is made of the above optical glass.

[0022] An optical element, which is made of the above optical glass or made of the above glass preform.

[0023] An optical device, which contains the above optical glass and / or contains the above optical element.

Advantages of the Invention

[0024] As a beneficial effect of the present invention, through reasonable composition design, the present invention can obtain an optical glass with excellent chemical stability at low raw material cost.

Embodiments for Carrying Out the Invention

[0025] 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. For overlapping description parts, the description may be omitted as appropriate, but the gist of the invention is not limited thereby. Hereinafter, the optical glass of the present invention may be simply referred to as glass.

[0026] [Optical Glass] Hereinafter, the ranges of the respective compositions (components) 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 composition are all expressed in weight percentage (wt%), that is, the weight percentage of the content and total content of each composition with respect to the total amount of the glass material in terms of oxide conversion composition. Here, the "oxide conversion composition" means that when oxides, double salts, hydroxides, etc. used as raw materials for the composition components of the optical glass of the present invention decompose into oxides during melting, the total amount of the oxides is set to 100%.

[0027] The numerical ranges described in the present invention include the upper limit value and the lower limit value unless otherwise specified in a particular case, and "more than" and "less than" include the end point values, and all integers and fractions included within this range, and are not limited to the specific values described when the range is limited. As used herein, "and / or" is inclusive, for example, "A and / or B" means only A, or only B, or both A and B.

[0028] <Essential components and optional components> SiO 2 has the functions of adjusting the optical constants, improving the chemical stability of the glass, maintaining a viscosity suitable for the molten glass, reducing the abrasion degree, and reducing the erosion of the refractory. In the present invention, by containing SiO 2 at 2% or more, the above effects can be achieved. Preferably, the content of SiO 2 is 3% or more, and more preferably, the content of SiO 2 is 4% or more. If the content of SiO 2 is too high, the melting difficulty of the glass increases and the transition temperature becomes high. Therefore, in the present invention, the upper limit of the content of SiO 2 is 20%, preferably 15%, and more preferably 10%.

[0029] B 2 O 3 improves the meltability and devitrification resistance of the glass and is advantageous for reducing the transition temperature of the glass. The present invention is directed to B 2 O 3Contain 3% or more, preferably B 2 O 3 Contain 5% or more, more preferably B 2 O 3 Achieve the above effects by containing 7% or more. B 2 O 3 If the content of B 2 O 3 is too high, the chemical stability of the glass, especially the water resistance, will deteriorate, and the refractive index and light transmittance of the glass will decrease. Therefore, the content of B

[0030] La 2 O 3 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. If its content is less than 35%, it will be difficult to reach the desired optical constants. If its content exceeds 60%, the devitrification tendency of the glass will increase and the thermal stability will deteriorate. Therefore, the content of La 2 O 3 is limited to 35% - 60%, preferably limited to 38% - 60%, more preferably limited to 41% - 55%.

[0031] Y 2 O 3 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, the above effects are achieved by containing 5% or more of Y 2 O 3 If its content exceeds 30%, the chemical stability and weather resistance of the glass will deteriorate. Therefore, in the present invention, the content of Y 2 O 3 is 5% - 30%, preferably 7% - 24%, more preferably 8% - 22%, and even more preferably 11% - 22%.

[0032] In some embodiments, the ratio between the content of Y 2 O 3 and the content of B 2 O 3 Y2 O 3 / B 2 O 3 By controlling Y 2 2 O 3 / B 2 O 3 within the range of 0.5 to 5.0, it is advantageous for the glass to obtain an appropriate Young's modulus. Therefore, preferably, Y 2 2 O 3 / B 2 O 3 is 0.5 to 5.0, and more preferably, Y 2 2 O 3 / B 2 O 3 By controlling Y 2 2 O 3 / B 2 O 3 within the range of 0.7 to 2.5, it is advantageous to further reduce the thermal expansion coefficient of the glass and optimize the bubble degree of the glass. Therefore, more preferably, Y 2 2 O 3 / B 2 O 3 is 0.7 to 2.5, and even more preferably, Y 2

[0033] Gd 2 O 3 can improve the refractive index and chemical stability of the glass, but when its content exceeds 8%, the devitrification resistance and wear degree of the glass deteriorate. Therefore, the content of Gd 2 2 O 3 is 0 to 8%, preferably 0 to 5%, and more preferably 0 to 3%.

[0034] In some embodiments, the ratio of the content of Gd 2 2 O 3 to the total content of SiO 2 2 and B 2 2 O 3 Gd 2 2 +B 2 O 3 O 2 2 O 3 / (SiO 2 2 +B 2O 3 ) By controlling it to 1.0 or less, the density of the glass can be reduced, and the bubble degree and wear degree of the glass can be optimized. Therefore, preferably, Gd 2 O 3 / (SiO 2 +B 2 O 3 ) is 1.0 or less, more preferably, Gd 2 O 3 / (SiO 2 +B 2 O 3 ) is 0.8 or less, even more preferably, Gd 2 O 3 / (SiO 2 +B 2 O 3 ) is 0.5 or less, and even more preferably, Gd 2 O 3 / (SiO 2 +B 2 O 3 ) is 0.3 or less.

[0035] In some embodiments, by controlling the total content of La 2 O 3 , Y 2 O 3 and Gd 2 O 3 La 2 O 3 +Y 2 O 3 +Gd 2 O 3 within the range of 45% to 75%, it is easier 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, preferably, La 2 O 3 +Y 2 O 3 +Gd 2 O 3 is 45% to 75%, more preferably, La 2 O 3 +Y 2 O 3 +Gd 2 O 3 is 50% to 75%, even more preferably, La 2 O3 +Y 2 O 3 +Gd 2 O 3 is 55% to 70%, and more preferably, La 2 O 3 +Y 2 O 3 +Gd 2 O 3 is 60% to 70%.

[0036] Yb 2 O 3 is also a component that imparts high refractive index and low dispersion performance to the glass. When its content exceeds 8%, the devitrification resistance performance of the glass decreases. Therefore, Yb 2 O 3 has a content of 0 to 8%, preferably 0 to 5%, more preferably 0 to 3%, and even more preferably, Yb 2 O 3 is not contained.

[0037] ZrO 2 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. When the content of ZrO 2 is too high, the devitrification resistance of the glass decreases, melting becomes difficult, the melting temperature rises, inclusions enter the glass interior, and the light transmittance decreases. Therefore, in the present invention, the content of ZrO 2 is 2% to 15%, preferably 3% to 13%, more preferably 4% to 10%.

[0038] In some embodiments, the total content of La 2 O 3 and Y 2 O 3 La 2 O 3 +Y 2 O 3 and the content of ZrO 2 The ratio (La 2 O 3 +Y 2 O 3 ) / ZrO 2By controlling it to be 4.0 or more, it is easy for the glass to obtain a desired Young's modulus and is advantageous for reducing the density of the glass. Therefore, preferably, (La 2 O 3 +Y 2 O 3 ) / ZrO 2 is 4.0 or more, and more preferably, (La 2 O 3 +Y 2 O 3 ) / ZrO 2 is 5.0 to 20.0. Further, by controlling (La 2 O 3 +Y 2 O 3 ) / ZrO 2 within the range of 6.0 to 13.0, the weather resistance and hardness of the glass can be further optimized. Therefore, more preferably, (La 2 O 3 +Y 2 O 3 ) / ZrO 2 is 6.0 to 13.0, and even more preferably, (La 2 O 3 +Y 2 O 3 ) / ZrO 2 is 7.0 to 11.0.

[0039] TiO 2 can improve the refractive index of the glass, but if its content is too high, it will significantly reduce the dispersion coefficient, increase the devitrification tendency, and ultimately significantly color the glass. Therefore, the content of TiO 2 is limited to 0 to 5%, preferably limited to 0 to 3%, more preferably limited to 0 to 2%, and even more preferably, TiO 2 is not contained.

[0040] Nb 2 O 5 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, Nb 2 O 5By containing 1% or more, the above effects can be achieved. Preferably, Nb 2 O 5 The lower limit of the content is 2%, more preferably 3%. Nb 2 O 5 When the content of exceeds 15%, 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 Nb 2 O 5 is 15%, preferably 10%, more preferably 8%.

[0041] In some embodiments, by controlling the ratio of the content of La 2 O 3 to the content of Nb 2 O 5 La 2 O 3 / Nb 2 O 5 to 3.0 or more, the hardness of the glass can be improved, the decrease in light transmittance can be prevented, and the glass can obtain a suitable Young's modulus. Therefore, preferably, La 2 O 3 / Nb 2 O 5 is 3.0 or more, more preferably, La 2 O 3 / Nb 2 O 5 is 4.0 to 30.0, still more preferably, La 2 O 3 / Nb 2 O 5 is 5.0 to 20.0, even more preferably, La 2 O 3 / Nb 2 O 5 is 6.0 to 12.0.

[0042] Alkaline earth metal oxides RO (RO is one or more of MgO, CaO, SrO, BaO) can adjust the optical constants of glass and optimize the chemical stability of glass. However, when its content is high, the devitrification resistance of glass decreases. Therefore, the content of RO is limited to 0 to 8%, preferably limited to 0 to 3%, and more preferably limited to 0 to 2%. In some embodiments, more preferably, RO is not contained.

[0043] Alkali metal oxides Rn 2 O (Rn 2 O is one or more of Li 2 O, Na 2 O, K 2 O) can lower the glass transition temperature, adjust the optical constants and high-temperature viscosity of glass, and improve the meltability of glass. However, when its content is high, the devitrification resistance and chemical stability of glass decrease. Therefore, in the present invention, the content of Rn 2 O is 0 to 8%, preferably 0 to 3%, and more preferably 0 to 2%. In some embodiments, more preferably, Rn 2 O is not contained.

[0044] WO 3 can improve the refractive index and mechanical strength of glass. When the content of WO 3 exceeds 5%, the thermal stability of glass decreases and the devitrification resistance decreases. Therefore, the upper limit of the content of WO 3 is 5%, preferably 3%, and more preferably 2%. In some embodiments, more preferably, WO 3 is not contained.

[0045] In some embodiments, TiO 2 and WO 3 The total content of TiO 2 +WO 3 and the content of Y 2 O 3 The ratio of (TiO 2 +WO 3 ) / Y 2 O3 By controlling it to 1.0 or less, the chemical stability and bubble degree of the glass can be improved. Therefore, preferably, (TiO 2 +WO 3 ) / Y 2 O 3 is 1.0 or less, and more preferably, (TiO 2 +WO 3 ) / Y 2 O 3 is 0.8 or less. Furthermore, by controlling (TiO 2 +WO 3 ) / Y 2 O 3 to 0.5 or less, the wear degree of the glass can be further optimized and an increase in the thermal expansion coefficient of the glass can be prevented. Therefore, more preferably, (TiO 2 +WO 3 ) / Y 2 O 3 is 0.5 or less, and even more preferably, (TiO 2 +WO 3 ) / Y 2 O 3 is 0.1 or less.

[0046] ZnO can adjust the refractive index and dispersion of the glass and reduce the high-temperature viscosity and transition temperature of the glass. If the content of ZnO is too high, the difficulty of glass forming increases and the devitrification resistance performance deteriorates. Therefore, the content of ZnO is 0 to 8%, preferably 0 to 4%, and more preferably 0 to 2%. In some embodiments, more preferably, ZnO is not contained.

[0047] In some embodiments, the total content of Gd 2 O 3 and ZnO, Gd 2 O 3 +ZnO, and the content of Y 2 O 3 The ratio of (Gd 2 O 3 +ZnO) / Y 2 O 3By controlling it to 1.0 or less, the thermal expansion coefficient of the glass can be reduced, and the wear degree of the glass can be optimized. Therefore, preferably, (Gd 2 O 3 +ZnO) / Y 2 O 3 is 1.0 or less, and more preferably, (Gd 2 O 3 +ZnO) / Y 2 O 3 is 0.8 or less. Further, by controlling (Gd 2 O 3 +ZnO) / Y 2 O 3 to 0.5 or less, the glass can easily obtain an appropriate Young's modulus and prevent a decrease in the hardness of the glass. Therefore, more preferably, (Gd 2 O 3 +ZnO) / Y 2 O 3 is 0.5 or less, and even more preferably, (Gd 2 O 3 +ZnO) / Y 2 O 3 is 0.3 or less.

[0048] Ta 2 O 5 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 decreases, the density increases, and it becomes difficult to control the optical constants within the desired range. On the other hand, compared with other components, Ta 2 O 5 is very expensive, and from the viewpoints of practicality and economy, it is necessary to minimize its usage amount. Therefore, in the present invention, the content of Ta 2 O 5 is limited to 0 to 15%, preferably limited to 2 to 12%, and more preferably limited to 5 to 10%.

[0049] In some embodiments, the content of Y 2 O 3 and the total content of Ta 2 O 5 and ZnO, Ta2 O 5 Ratio Y with ZnO 2 O 3 / (Ta 2 O 5 +ZnO) is controlled within the range of 0.5 to 8.0, which is advantageous for improving the chemical stability of the glass, preventing a decrease in light transmittance, and improving the hardness of the glass. Therefore, preferably, Y 2 O 3 / (Ta 2 O 5 +ZnO) is 0.5 to 8.0, more preferably, Y 2 O 3 / (Ta 2 O 5 +ZnO) is 0.7 to 5.0, even more preferably, Y 2 O 3 / (Ta 2 O 5 +ZnO) is 0.8 to 4.0, and even more preferably, Y 2 O 3 / (Ta 2 O 5 +ZnO) is 1.0 to 3.0.

[0050] In some embodiments, the total content of Ta 2 O 5 and Gd 2 O 3 Ta 2 O 5 +Gd 2 O 3 and the content of Nb 2 O 5 Ratio (Ta 2 O 5 +Gd 2 O 3 ) / Nb 2 O 5 is controlled within the range of 0.3 to 8.0, which can improve the chemical stability of the glass and reduce the thermal expansion coefficient of the glass. Therefore, preferably, (Ta 2 O 5 +Gd 2 O 3 ) / Nb 2 O 5is from 0.3 to 8.0, more preferably, (Ta 2 O 5 +Gd 2 O 3 ) / Nb 2 O 5 is from 0.5 to 6.0. Further preferably, (Ta 2 O 5 +Gd 2 O 3 ) / Nb 2 O 5 is in the range of 0.6 to 5.0, which is advantageous for the optimization of the density and Young's modulus of the glass. Therefore, more preferably, (Ta 2 O 5 +Gd 2 O 3 ) / Nb 2 O 5 is from 0.6 to 5.0, and more preferably, (Ta 2 O 5 +Gd 2 O 3 ) / Nb 2 O 5 is from 0.8 to 3.0.

[0051] Al 2 O 3 can improve the chemical stability of the glass, but when its content exceeds 8%, the meltability and light transmittance of the glass deteriorate. Therefore, in the present invention, the content of Al 2 O 3 is from 0 to 8%, preferably from 0 to 4%, and more preferably from 0 to 2%. In some embodiments, more preferably, Al 2 O 3 is not contained.

[0052] GeO 2 has the effect of improving the refractive index and devitrification resistance, but when its content is too high, the chemical stability of the glass decreases. On the other hand, compared with other components, GeO 2 is very expensive, and it is necessary to minimize its usage amount from the viewpoints of practicality and economy. Therefore, in the present invention, GeO 2The content is limited to 0 to 5%, preferably limited to 0 to 3%, more preferably limited to 0 to 1%, and even more preferably, GeO 2 is not contained.

[0053] In the present invention, 0 to 2% of Sb 2 O 3 , SnO, SnO 2 , CeO 2 By containing one or more of them as a fining agent, 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%, and more preferably 0 to 0.5%. Since the optical glass of the present invention has a reasonable design of the types and contents of the components and is excellent in bubble degree, in some embodiments, more preferably, it does not contain a fining agent. When the content of Sb 2 O 3 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 container for melting the glass and the deterioration of the molding die are promoted. Therefore, in the present invention, the content of Sb 2 O 3 is preferably 0 to 2%, more preferably 0 to 1%, even more preferably 0 to 0.5%, and even more preferably, Sb 2 O 3 is not contained. SnO and SnO 2 may be used as a fining agent, but when its content exceeds 2%, the coloring tendency of the glass increases, or when the glass is heated and softened and remolded by press molding or the like, Sn tends to become a starting point for crystal nucleation and devitrify. Therefore, the content of SnO 2 in the present invention is preferably 0 to 2%, more preferably 0 to 1%, even more preferably 0 to 0.5%, and even more preferably, it does not contain SnO 2 , and the content of SnO is preferably 0 to 2%, more preferably 0 to 1%, even more preferably 0 to 0.5%, and even more preferably, it does not contain SnO. The action and content ratio of CeO 2 are the same as those of SnO 2It coincides, and its content is preferably 0 to 2%, more preferably 0 to 1%, still more preferably 0 to 0.5%, and even more preferably, CeO 2 is not contained.

[0054] In some embodiments, in order to endow the optical glass of the present invention with a low coefficient of thermal expansion and density, high hardness and light transmittance, excellent chemical stability, and appropriate wear resistance and Young's modulus, preferably, SiO 2 , B 2 O 3 , La 2 O 3 , Y 2 O 3 , ZrO 2 , Nb 2 O 5 , Ta 2 O 5 The total content of is 85% or more, more preferably, SiO 2 , B 2 O 3 , La 2 O 3 , Y 2 O 3 , ZrO 2 , Nb 2 O 5 , Ta 2 O 5 The total content of is 88% or more, still more preferably, SiO 2 , B 2 O 3 , La 2 O 3 , Y 2 O 3 , ZrO 2 , Nb 2 O 5 , Ta 2 O 5 The total content of is 90% or more, and even more preferably, SiO 2 , B 2 O 3 , La 2 O 3 , Y 2 O 3 , ZrO 2 , Nb 2 O 5 , Ta 2O 5 The total content is 95% or more.

[0055] <Prohibited components> In the glass of the present invention, oxides of transition metals such as V, Cr, Mn, Fe, Co, Ni, Cu, Ag, and Mo, even when contained in a small amount alone or in combination, cause the glass to be colored and absorption occurs at specific wavelengths in the visible light region, thereby weakening the property of the present invention of improving the visible light transmittance effect. Therefore, for optical glass that requires transmittance at wavelengths in the visible light region, it is preferably not substantially contained.

[0056] Oxides of Th, Cd, Tl, Os, Be, and Se have recently tended to be restricted from use as harmful chemical substances, and measures for environmental protection are required not only in the glass manufacturing process but also in the processing process and disposal after productization. Therefore, when emphasizing the impact on the environment, it is preferably not substantially contained except for inevitable contamination. As a result, the optical glass will substantially not 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] For environmental considerations, preferably, the optical glass of the present invention does not contain As 2 O 3 and PbO.

[0058] As used herein, "not contained" and "0%" mean that the compound, molecule, element, etc. is not intentionally added to the optical glass of the present invention as a raw material. However, as raw materials and / or equipment for producing the optical glass, there may be some impurities and components that are not intentionally added and are contained in a small or trace amount in the final optical glass. Such cases are also within the protection scope of the present invention patent.

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

[0060] <Refractive index and Abbe number> Refractive index (n) of the optical glass d ) and Abbe number (ν d ) are tested according to the method specified in 'GB / T7962.1-2010'.

[0061] In some embodiments, the lower limit of the refractive index (n d ) of the optical glass of the present invention is 1.86, preferably 1.87, and more preferably 1.88.

[0062] In some embodiments, the upper limit of the refractive index (n d ) of the optical glass of the present invention is 1.92, preferably 1.91, and more preferably 1.90.

[0063] In some embodiments, the lower limit of the Abbe number (ν d ) of the optical glass of the present invention is 36, preferably 38, and more preferably 39.

[0064] In some embodiments, the upper limit of the Abbe number (ν d ) of the optical glass of the present invention is 44, preferably 43, and more preferably 42.

[0065] <Density> The density (ρ) of the optical glass is tested according to the method specified in 'GB / T7962.20-2010'.

[0066] In some embodiments, the density (ρ) of the optical glass of the present invention is 5.20 g / cm 3 or less, preferably 5.15 g / cm 3 or less, and more preferably 5.10 g / cm 3 or less.

[0067] <Coefficient of thermal expansion> The coefficient of thermal expansion (α 20 / 120℃ ) of the optical glass is tested for data at 20°C to 120°C according to the method specified in 'GB / T7962.16-2010'.

[0068] In some embodiments, the coefficient of thermal expansion (α 20 / 120℃ ) of the optical glass of the present invention is 85×10 -7 / K or less, preferably 80×10 -7 / K or less, more preferably 75×10 -7 / K or less.

[0069] <Water resistance stability> The water resistance stability (D W ) of the optical glass is tested according to the method specified in 'GB / T17129' (powder method).

[0070] In some embodiments, the water resistance stability (D W ) of the optical glass of the present invention is class 2 or higher, preferably class 1.

[0071] <Degree of coloring> The short - wave transmission spectral characteristics of the glass of the present invention are represented by the degree of coloring (λ 70 and λ 5 ). λ 70 means the corresponding wavelength when the glass transmittance reaches 70%. The measurement of λ 70 is carried out using a glass having two opposing planes that are parallel to each other and optically polished (thickness 10 ± 0.1 mm), measuring the spectral transmittance in the wavelength range of 280 nm to 700 nm, and using the wavelength showing a transmittance of 70%. So - called spectral transmittance or transmittance means the amount represented by I in of light perpendicularly incident on the above - mentioned surface of the glass and transmitted through the glass and emerging as light of intensity I out from one plane, that is, I out / I in , and it is the transmittance including the surface reflection loss on the above - mentioned surface of the glass. The higher the refractive index of the glass, the greater the surface reflection loss. Therefore, in a high - refractive - index glass, the small value of λ 70 means that the coloring of the glass itself is extremely small and the light transmittance is high.

[0072] In some embodiments, λ 70is 400 nm or less, preferably, λ 70 is 390 nm or less, more preferably, λ 70 is 385 nm or less.

[0073] In some embodiments, the λ of the optical glass of the present invention 5 is 340 nm or less, preferably, λ 5 is 330 nm or less, more preferably, λ 5 is 325 nm or less.

[0074] <Weather resistance> The test method for the weather resistance (CR) of the optical glass is as follows. The sample is placed in a test chamber with a saturated water vapor atmosphere at a relative humidity of 90%, and alternately circulated 15 cycles at 1-hour intervals between 40 °C and 50 °C. The class of weather resistance is classified by the amount of turbidity change before and after leaving the sample, and the classification status of weather resistance is shown in Table 1.

Table 1

[0075] In some embodiments, the weather resistance (CR) of the optical glass of the present invention is Class 2 or higher, preferably Class 1.

[0076] <Knoop hardness> The Knoop hardness (H K ) of the optical glass is tested according to the test method specified in "GB / T7962.18-2010".

[0077] In some embodiments, the Knoop hardness (H K ) of the optical glass of the present invention is 690×10 7 Pa or more, preferably 700×10 7 Pa or more, more preferably 710×10 7 Pa or more.

[0078] <Young's modulus> The Young's modulus (E) is calculated by the following formula by measuring the longitudinal wave velocity and the transverse wave velocity with ultrasonic waves.

Number

[0079] In some embodiments, the lower limit of the Young's modulus (E) of the optical glass of the present invention is 10500×10 7 Pa, preferably 11000×10 7 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 14500×10 7 Pa, preferably 14000×10 7 Pa, more preferably 13500×10 7 Pa.

[0081] <Bubble degree> The bubble degree of the optical glass is tested according to the method specified in "GB / T7962.8-2010".

[0082] In some embodiments, the bubble degree of the optical glass of the present invention is level A or above, preferably level A 0 or above, more preferably level A 00 .

[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 using ordinary raw materials and processes, and uses raw materials including, but not limited to, oxides, hydroxides, double salts (such as carbonates, nitrates, sulfates, etc.), boric acid, etc. After blending the raw materials in the usual way, the blended furnace materials are put into a melting furnace (such as a platinum or platinum alloy crucible) at 1200°C to 1450°C for melting. After clarification and homogenization, a homogeneous molten glass without bubbles and free of undissolved substances is obtained, and this molten glass is cast into a mold and annealed for manufacturing. Those skilled in the art can appropriately select raw materials, process methods, and process parameters according to actual needs.

[0084] [Glass preform and optical element] From the manufactured optical glass, a glass preform can be manufactured using, for example, direct gob forming, or means such as grinding, or press forming means such as hot press forming. That is, precision gob forming is directly performed on the molten optical glass to manufacture a glass precision preform, or machining such as grinding and polishing is performed to manufacture a glass preform, or a preform for press forming is manufactured from the optical glass, and after reheating and press forming the preform, it is polished to manufacture a glass preform. Note that the means for manufacturing the glass preform 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. In particular, it is preferable to form a preform from the optical glass of the present invention and perform reheat press forming, precision press forming, etc. using the preform to manufacture optical elements such as lenses and prisms.

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

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

[0088] [Optical device] The optical element formed from the optical glass of the present invention can be used to manufacture optical devices such as camera devices, imaging devices, projection devices, display devices, in-vehicle devices, and monitoring devices.

[0089] Examples [Examples of optical glass] In order to more clearly interpret and explain the technical solution means of the present invention, the following non-limiting examples are provided.

[0090] In this example, optical glass having the compositions shown in Tables 2 to 4 is obtained by the above-described method for manufacturing optical glass. Further, the characteristics of each glass are measured by the test method described in the present invention, and the measurement results are shown in Tables 2 to 4. [Table 2] TIFF2025518149000004.tif61170 [Table 3] TIFF2025518149000006.tif61170 [Table 4] TIFF2025518149000008.tif61170

[0091] [Examples of glass preforms] From the glass obtained in Examples 1 to 24# of the optical glass, various lenses such as concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, and plano-concave lenses, and preforms such as prisms are manufactured using means such as polishing or press-forming means such as reheat press forming and precision press forming.

[0092] <Examples of optical elements> These preforms obtained in the examples of the glass preform are annealed to finely adjust the refractive index while reducing the internal stress of the glass so that optical properties such as the refractive index reach desired values.

[0093] Next, each preform 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 can also be applied to the surface of the obtained optical element.

[0094] <Examples of optical devices> From the optical elements manufactured from the examples of the optical elements above, by optical design, one or more optical elements are used to form an optical member or optical assembly, and thus can be used, for example, in imaging devices, sensors, microscopes, medical technology, digital projection, communication, optical communication technology / information transmission, optical / lighting in the automotive field, lithography technology, excimer lasers, wafers, computer chips, and integrated circuits and electronic devices including such circuits and chips.

Claims

1. When the composition is expressed as a weight percentage, SiO ２ : 2% to 20%, B ２ O ３ : 3% to 20%, La ２ O ３ : 35% to 60%, Y ２ O ３ : 5% to 30%, ZrO ２ : 2% to 15%, Nb ２ O ５ : 1% to 15%, and Ta ２ O ５ : 0 to 15%, characterized by an optical glass containing the same.

2. When the composition is expressed in weight percentage, Gd ２ O ３ : 0 to 8%, and / or TiO ２ : 0 to 5%, and / or RO: 0 to 8%, and / or Rn ２ O: 0 to 8%, and / or WO ３ : 0 to 5%, and / or ZnO: 0 to 8%, and / or Al ２ O ３ : 0 to 8%, and / or Yb ２ O ３ : 0 to 8%, and / or GeO ２ : 0 to 5%, and further contains a clarifying agent: 0 to 2%, 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 of one or more of the above, and the optical glass according to claim 1, characterized in that.

3. When the composition is expressed in weight percentage, SiO ２ : 2% to 20%, B ２ O ３ : 3% to 20%, La ２ O ３ : 35% to 60%, Y ２ O ３ : 5% to 30%, ZrO ２ : 2% to 15%, Nb ２ O ５ : 1% to 15%, Ta ２ O ５ : 0 to 15%, Gd ２ O ３ : 0 to 8%, TiO ２ : 0 to 5%, RO: 0 to 8%, Rn ２ O: 0 to 8%, WO ３ : 0 to 5%, ZnO: 0 to 8%, Al ２ O ３ : 0 to 8%, Yb ２ O ３ : 0 to 8%, GeO ２ : 0 to 5%, and consists of 0 to 2% of fining agent, wherein the RO is one or more of MgO, CaO, SrO, BaO, Rn ２ O is one or more of Li ２ O, Na ２ O, K ２ O, and the fining agent is one or more of Sb ２ O ３ 、SnO、SnO ２ 、CeO ２ One or more of them, and is characterized by an optical glass.

4. When the composition is expressed as a weight percentage, La ２ O ３ + Y ２ O ３ + Gd ２ O ３ is 45% to 75%, preferably, La ２ O ３ + Y ２ O ３ + Gd ２ O ３ is 50% to 75%, more preferably, La ２ O ３ + Y ２ O ３ + Gd ２ O ３ is 55% to 70%, still more preferably, La ２ O ３ + Y ２ O ３ + Gd ２ O ３ is 60% to 70%, and the optical glass according to any one of claims 1 to 3, characterized in that.

5. When the composition is expressed in weight percentages, Y ２ O ３ / B ２ O ３ is 0.5 to 5.0, preferably, Y ２ O ３ / B ２ O ３ is 0.6 to 3.0, more preferably, Y ２ O ３ / B ２ O ３ is 0.7 to 2.5, even more preferably, Y ２ O ３ / B ２ O ３ is 0.8 to 2.0, and the optical glass according to any one of claims 1 to 3 is characterized by this.

6. When the composition is expressed in weight percentage, Gd ２ O ３ / (SiO ２ + B ２ O ３ ) is 1.0 or less, preferably, Gd ２ O ３ / (SiO ２ + B ２ O ３ ) is 0.8 or less, more preferably, Gd ２ O ３ / (SiO ２ + B ２ O ３ ) is 0.5 or less, still more preferably, Gd ２ O ３ / (SiO ２ + B ２ O ３ ) is 0.3 or less, The optical glass according to any one of claims 1 to 3, characterized in that.

7. When the composition is expressed in weight percentage, (La ２ O ３ + Y ２ O ３ ) / ZrO ２ is 4.0 or more, preferably, (La ２ O ３ + Y ２ O ３ ) / ZrO ２ is 5.0 to 20.0, more preferably, (La ２ O ３ + Y ２ O ３ ) / ZrO ２ is 6.0 to 13.0, still more preferably, (La ２ O ３ + Y ２ O ３ ) / ZrO ２ is 7.0 to 11.0, and the optical glass according to any one of claims 1 to 3, characterized in that.

8. When the composition is expressed in weight percentage, Y ２ O ３ / (Ta ２ O ５ + ZnO) is 0.5 to 8.0, preferably, Y ２ O ３ / (Ta ２ O ５ + ZnO) is 0.7 to 5.0, more preferably, Y ２ O ３ / (Ta ２ O ５ + ZnO) is 0.8 to 4.0, still more preferably, Y ２ O ３ / (Ta ２ O ５ + ZnO) is 1.0 to 3.0, and the optical glass according to any one of claims 1 to 3 is characterized in that.

9. When the composition is expressed in weight percentage, La ２ O ３ / Nb ２ O ５ is 3.0 or more, preferably, La ２ O ３ / Nb ２ O ５ is 4.0 to 30.0, more preferably, La ２ O ３ / Nb ２ O ５ is 5.0 to 20.0, still more preferably, La ２ O ３ / Nb ２ O ５ is 6.0 to 12.0, and the optical glass according to any one of claims 1 to 3, characterized in that.

10. When the composition is expressed as a weight percentage, (Ta ２ O ５ + Gd ２ O ３ ) / Nb ２ O ５ is 0.3 to 8.0, preferably, (Ta ２ O ５ + Gd ２ O ３ ) / Nb ２ O ５ is 0.5 to 6.0, more preferably, (Ta ２ O ５ + Gd ２ O ３ ) / Nb ２ O ５ is 0.6 to 5.0, still more preferably, (Ta ２ O ５ + Gd ２ O ３ ) / Nb ２ O ５ is 0.8 to 3.0, and the optical glass according to any one of claims 1 to 3 is characterized in that.

11. When the composition is expressed as a weight percentage, (TiO ２ + WO ３ ) / Y ２ O ３ is 1.0 or less, preferably, (TiO ２ + WO ３ ) / Y ２ O ３ is 0.8 or less, more preferably, (TiO ２ + WO ３ ) / Y ２ O ３ is 0.5 or less, still more preferably, (TiO ２ + WO ３ ) / Y ２ O ３ is 0.1 or less, The optical glass according to any one of claims 1 to 3, characterized in that.

12. When the composition is expressed as a weight percentage, (Gd ２ O ３ + ZnO) / Y ２ O ３ is 1.0 or less, preferably, (Gd ２ O ３ + ZnO) / Y ２ O ３ is 0.8 or less, more preferably, (Gd ２ O ３ + ZnO) / Y ２ O ３ is 0.5 or less, still more preferably, (Gd ２ O ３ + ZnO) / Y ２ O ３ is 0.3 or less, and the optical glass according to any one of claims 1 to 3 is characterized by this.

13. When the composition is expressed as a weight percentage, SiO ２ : 3% to 15%, preferably, SiO ２ : 4% to 10%, and / or, B ２ O ３ : 5% to 15%, preferably, B ２ O ３ : 7% to 13%, and / or, La ２ O ３ : 38% to 60%, preferably, La ２ O ３ : 41% to 55%, and / or, Y ２ O ３ : 7% to 24%, preferably, Y ２ O ３ : 8% to 22%, more preferably, Y ２ O ３ : 11% to 22%, and / or, ZrO ２ : 3% to 13%, preferably, ZrO ２ : 4% to 10%, and / or, Nb ２ O ５ : 2% to 10%, preferably, Nb ２ O ５ : 3% to 8%, and / or, Ta ２ O ５ : 2% to 12%, preferably, Ta ２ O ５ : 5% to 10%, and / or, Gd ２ O ３ : 0 to 5%, preferably, Gd ２ O ３ : 0 to 3%, and / or, TiO ２ : 0 to 3%, preferably, TiO ２ : 0 to 2%, and / or, RO: 0 to 3%, preferably, RO: 0 to 2%, and / or, Rn ２ O: 0 to 3%, preferably, Rn ２ O: 0 to 2%, and / or, WO ３ : 0 to 3%, preferably, WO ３ : 0 to 2%, and / or, ZnO: 0 to 4%, preferably, ZnO: 0 to 2%, and / or, Al ２ O ３ : 0 to 4%, preferably, Al ２ O ３ : 0 to 2%, and / or, Yb ２ O ３ : 0 to 5%, preferably, Yb ２ O ３ : 0 to 3%, and / or GeO ２ : 0 to 3%, preferably, GeO ２ : 0 to 1%, and / or fining agent: 0 to 1%, preferably, fining agent: 0 to 0.5%, wherein RO is one or more of MgO, CaO, SrO, BaO, and Rn ２ O is Li ２ O, Na ２ O, K ２ O, and the fining agent is one or more of Sb ２ O ３ , SnO, SnO ２ , CeO ２ of claim 1 to 3, characterized in that the optical glass according to any one of.

14. The composition does not contain WO ３ and / or does not contain TiO ２ and / or does not contain RO and / or does not contain Rn ２ O and / or does not contain ZnO and / or does not contain Al ２ O ３ and / or does not contain GeO ２ 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 optical glass according to any one of claims 1 to 3, characterized in that.

15. When the composition is expressed as a weight percentage, SiO ２ 、B ２ O ３ 、La ２ O ３ 、Y ２ O ３ 、ZrO ２ 、Nb ２ O ５ 、Ta ２ O ５ The total content of is 85% or more, preferably, SiO ２ 、B ２ O ３ 、La ２ O ３ 、Y ２ O ３ 、ZrO ２ 、Nb ２ O ５ 、Ta ２ O ５ The total content of is 88% or more, more preferably, SiO ２ 、B ２ O ３ 、La ２ O ３ 、Y ２ O ３ 、ZrO ２ 、Nb ２ O ５ 、Ta ２ O ５ The total content of is 90% or more, still more preferably, SiO ２ 、B ２ O ３ 、La ２ O ３ 、Y ２ O ３ 、ZrO ２ 、Nb ２ O ５ 、Ta ２ O ５ The optical glass according to any one of claims 1 to 3, characterized in that the total content of is 95% or more.

16. The refractive index n of the optical glass ｄ is 1.86 to 1.92, preferably 1.87 to 1.91, more preferably 1.88 to 1.90, and the Abbe number ν ｄ is 36 to 44, preferably 38 to 43, more preferably 39 to 42, and the optical glass according to any one of claims 1 to 3 is characterized by this.

17. The density ρ of the optical glass is 5.20 g / cm ３ or less, preferably 5.15 g / cm ３ or less, more preferably 5.10 g / cm ３ or less, and / or the coefficient of thermal expansion α ２０／１２０℃ is 85×10 －７ / K or less, preferably 80×10 －７ / K or less, more preferably 75×10 －７ / K or less, and / or the water resistance stability D Ｗ is Class 2 or higher, preferably Class 1, and / or λ ７０ is 400 nm or less, preferably λ ７０ is 390 nm or less, more preferably λ ７０ is 385 nm or less, and / or λ ５ is 340 nm or less, preferably λ ５ is 330 nm or less, more preferably λ ５ is 325 nm or less, and / or the weather resistance CR is Class 2 or higher, preferably Class 1, and / or the Knoop hardness H Ｋ is 690×10 ７ Pa or higher, preferably 700×10 ７ Pa or higher, more preferably 710×10 ７ Pa or higher, and / or the Young's modulus E is 10500×10 ７ Pa to 14500×10 ７ Pa, preferably 11000×10 ７ Pa to 14000×10 ７ Pa, more preferably 11500×10 ７ Pa to 13500×10 ７ Pa, and / or the bubble degree is Level A or higher, preferably Level A ０ or higher, more preferably Level A ００ or higher, which is characterized in that the optical glass according to any one of claims 1 to 3

18. A glass preform, characterized in that it is made of the optical glass according to any one of Claims 1 to 17.

19. An optical element, characterized in that it is made of the optical glass according to any one of Claims 1 to 17, or is made of the glass preform according to Claim 18.

20. An optical device, characterized in that it contains the optical glass according to any one of Claims 1 to 17 and / or contains the optical element according to Claim 19.

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