Optical Glass, Optical Elements, and Optical Devices

Abstract

The present invention provides an optical glass, which contains the following components by weight: SiO2: 55-70%, B2O3: 2-18%, ZnO: 1-20%, La2O3+Y2O3+Gd2O3: 4-30%, Ta2O5+Nb2O5+TiO2+ZrO2: 0.5-20%, Li2O+Na2O+K2O: 3-15%, (La2O3+Y2O3+Gd2O3) / (Ta2O5+Nb2O5+TiO2+ZrO2) is 1.0-13.0. Due to the rational component design, the optical glass obtained by the present invention has a desired refractive index and Abbe number, and at the same time, has a high ultraviolet transmittance and excellent ultraviolet radiation resistance.

Description

Technical Field

[0001] The present invention relates to optical glass, and particularly to optical glass having a refractive index of 1.51 to 1.58 and an Abbe number of 55 to 65, and optical elements and optical devices manufactured therefrom.

Background Art

[0002] In recent years, ultraviolet rays in the 320-400 nm band have been widely applied in fields such as banknote forgery prevention, food packaging, metal detection, blood analysis, ultraviolet packaging, ultraviolet photolithography, and ultraviolet exposure systems. With the rapid development of the semiconductor manufacturing field, the requirements for the accuracy of ultraviolet packaging, ultraviolet photolithography, and ultraviolet exposure systems are increasing. Taking the objective lens system of an ultraviolet photolithography machine as an example, in order to achieve a high-precision effect, it is necessary to combine several to more than a dozen large-aperture lenses with different refractive indices and Abbe numbers. In an ultraviolet optical system in the 320-400 nm band, high transmittance and high irradiation resistance characteristics are required. Taking a high-precision optical system such as photolithography and exposure as an example, in order to obtain a higher yield, it is necessary to use ultraviolet rays with a power of kilowatts or higher. Under such high power, the glass material must have good ultraviolet irradiation resistance performance. When the transmittance of the glass decreases under ultraviolet band irradiation, the heat generation of the glass becomes intense, resulting in a deviation of the refractive index of the lens group and a deformation of the curved surface, and the imaging effect deteriorates.

[0003] Optical glass having a refractive index of 1.51 to 1.58 and an Abbe number of 55 to 65 belongs to barium crown glass based on the optical glass classification standard in China. The conventional barium crown glass has a transmittance in the ultraviolet band much lower than the usage requirements of photolithography. Especially in the most commonly used 365 nm band, the transmittance of the glass after irradiation decreases sharply, and it is not suitable for use in ultraviolet irradiation devices.

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 an optical glass with high ultraviolet transmittance and excellent ultraviolet irradiation resistance performance.

Means for Solving the Problem

[0005] The technical solution adopted by the present invention to solve the technical problem is as follows. Optical glass containing the following components by weight percentage: SiO2: 55 - 70%, B2O3: 2 - 18%, ZnO: 1 - 20%, La2O3 + Y2O3 + Gd2O3: 4 - 30%, Ta2O5 + Nb2O5 + TiO2 + ZrO2: 0.5 - 20%, Li2O + Na2O + K2O: 3 - 15%, (La2O3 + Y2O3 + Gd2O3) / (Ta2O5 + Nb2O5 + TiO2 + ZrO2) is 1.0 - 13.0.

[0006] Furthermore, the above optical glass further contains the following components by weight percentage: BaO + SrO + CaO + MgO: 0 - 15%, and / or Al2O3: 0 - 5%, and / or F: 0 - 3%, and / or fining agent: 0 - 1%, the fining agent is one or more of Sb2O3, SnO, SnO2, CeO2, Cl, Br.

[0007] Optical glass containing the following components by weight percentage: SiO2: 55 - 70%, B2O3: 2 - 18%, ZnO: 1 - 20%, La2O3 + Y2O3 + Gd2O3: 4 - 30%, Ta2O5 + Nb2O5 + TiO2 + ZrO2: 0.5 - 20%, Li2O + Na2O + K2O: 3 - 15%, BaO + SrO + CaO + MgO: 0 - 15%, Al2O3: 0 - 5%, F: 0 - 3%, fining agent: 0 - 1%, the fining agent is one or more of Sb2O3, SnO, SnO2, CeO2, Cl, Br.

[0008] Furthermore, the optical glass contains the following components by weight %: (La2O3 + Y2O3 + Gd2O3) / (Ta2O5 + Nb2O5 + TiO2 + ZrO2) is 1.0 to 13.0, preferably (La2O3 + Y2O3 + Gd2O3) / (Ta2O5 + Nb2O5 + TiO2 + ZrO2) is 2.0 to 10.0, more preferably (La2O3 + Y2O3 + Gd2O3) / (Ta2O5 + Nb2O5 + TiO2 + ZrO2) is 3.0 to 7.0.

[0009] Furthermore, the optical glass contains the following components by weight %: La2O3 / Nb2O5 is 3.5 to 15.0, preferably La2O3 / Nb2O5 is 5.0 to 14.0, more preferably La2O3 / Nb2O5 is 7.0 to 13.5.

[0010] Furthermore, the optical glass contains the following components by weight %: (La2O3 + Y2O3 + Gd2O3) / SiO2 is 0.07 to 0.35, preferably (La2O3 + Y2O3 + Gd2O3) / SiO2 is 0.08 to 0.3, more preferably (La2O3 + Y2O3 + Gd2O3) / SiO2 is 0.1 to 0.25.

[0011] Furthermore, the optical glass contains the following components by weight %: (B2O3 + Al2O3) / SiO2 is 0.05 to 0.4, preferably (B2O3 + Al2O3) / SiO2 is 0.08 to 0.35, more preferably (B2O3 + Al2O3) / SiO2 is 0.1 to 0.3.

[0012] Furthermore, the optical glass contains the following components by weight %: (BaO + SrO + CaO + MgO) / SiO2 is 0.01 to 0.25, preferably (BaO + SrO + CaO + MgO) / SiO2 is 0.01 to 0.2, more preferably (BaO + SrO + CaO + MgO) / SiO2 is 0.02 to 0.15, still more preferably (BaO + SrO + CaO + MgO) / SiO2 is 0.02 to 0.1.

[0013] Furthermore, the optical glass contains the following components by weight %: (La2O3 + Y2O3 + Gd2O3) / B2O3 is 0.3 to 6.0, preferably (La2O3 + Y2O3 + Gd2O3) / B2O3 is 0.4 to 5.0, more preferably (La2O3 + Y2O3 + Gd2O3) / B2O3 is 0.5 to 3.0.

[0014] Furthermore, the optical glass contains the following components by weight %: SiO2: 56 to 68%, preferably SiO2: 57 to 67%, and / or B2O3: 4 to 16%, preferably B2O3: 5 to 15%, and / or ZnO: 2 to 16%, preferably ZnO: 3 to 12%, and / or La2O3 + Y2O3 + Gd2O3: 5 to 20%, preferably La2O3 + Y2O3 + Gd2O3: 7 to 15%, and / or Ta2O5 + Nb2O5 + TiO2 + ZrO2: 1 to 15%, preferably Ta2O5 + Nb2O5 + TiO2 + ZrO2: 2 to 10%, and / or Li2O + Na2O + K2O: 5 to 14%, preferably Li2O + Na2O + K2O: 6 to 13%, and / or BaO + SrO + CaO + MgO: 1 to 15%, preferably BaO + SrO + CaO + MgO: 1.5 to 10%, more preferably BaO + SrO + CaO + MgO: 1.5 to 8%, and / or Al2O3: 0 to 4%, preferably Al2O3: 0 to 3%, and / or F: 0 to 2%, preferably F: 0 to 1%, and / or fining agent: 0 to 0.8%, preferably fining agent: 0 to 0.5%, and the fining agent is one or more of Sb2O3, SnO, SnO2, CeO2, Cl, Br.

[0015] Furthermore, the optical glass contains the following components by weight percentage: La2O3: 4 to 25%, preferably La2O3: 6 to 20%, more preferably La2O3: 7 to 14%, and / or Gd2O3: 0 to 8%, preferably Gd2O3: 0 to 7%, more preferably Gd2O3: 0 to 5%, and / or Y2O3: 0 to 10%, preferably Y2O3: 0 to 8%, more preferably Y2O3: 0 to 5%, and / or Na2O: 2 to 15%, preferably Na2O: 4 to 14%, more preferably Na2O: 5 to 13%, and / or K2O: 0 to 8%, preferably K2O: 1 to 6%, more preferably K2O: 2 to 5%, and / or Li2O: 0 to 5%, preferably Li2O: 0 to 4%, more preferably Li2O: 0 to 3%.

[0016] Furthermore, the optical glass wherein the component does not contain F, and / or does not contain MgO, and / or does not contain CaO, and / or does not contain Li2O.

[0017] Furthermore, the refractive index n of the optical glass d is 1.51 to 1.58, preferably 1.52 to 1.57, more preferably 1.53 to 1.56, and / or the Abbe number v d is 55 to 65, preferably 56 to 63, more preferably 57 to 60. Furthermore, the τ of the optical glass 365nm is 99.0% or more, preferably 99.2% or more, more preferably 99.4% or more, still more preferably 99.5% or more, and / or Δτ 365nm is 5.0% or less, preferably 2.0% or less, more preferably 1.0% or less.

[0018] Furthermore, the water resistance stability D of the optical glass W is Class 2 or higher, preferably Class 1, and / or the acid resistance stability D A is Class 3 or higher, preferably Class 2 or higher, more preferably Class 1, and / or the refractive index temperature coefficient dn / dt is 8.0×10 -6 / ℃ or less, preferably 7.0×10 -6 / ℃ or less, more preferably 6.0×10 -6below / ℃ and / or the crystal upper limit temperature is 1300℃ or below, preferably 1280℃ or below, more preferably 1250℃ or below, still more preferably 1230℃ or below, and / or the bubble degree is Class A or above, preferably Class A0 or above, more preferably Class A 00 class, and / or the stripe is Class C or above, preferably Class B or above, and / or Δn d value is 5×10 -6 or below, preferably 3×10 -6 or below, more preferably 2×10 -6 or below.

[0019] A glass preform manufactured from the above optical glass.

[0020] An optical element manufactured from the above optical glass or the above glass preform.

[0021] An optical device including the above optical glass and / or the above optical element.

Advantages of the Invention

[0022] The beneficial effects of the present invention are as follows. Through reasonable component design, the optical glass obtained by the present invention has a desired refractive index and Abbe number, high ultraviolet transmittance, and excellent ultraviolet irradiation resistance performance.

Modes for Carrying Out the Invention

[0023] Hereinafter, embodiments of the optical glass according to the present invention will be described in detail. However, the present invention is not limited to the embodiments described below, and can be appropriately modified and implemented within the scope of the object of the present invention. Furthermore, although there are appropriate omissions, the gist of the present invention is not limited by repeating the description. Hereinafter, the optical glass of the present invention may sometimes be simply referred to as glass.

[0024] [Optical Glass] The following describes the ranges of the components of the optical glass of the present invention. In this specification, the content and total content of each component shall be expressed in weight percent (wt%) unless otherwise specified. That is, the content and total content of each component are expressed as weight percentages with respect to the total weight of the glass material converted into the oxide composition. The "converted into the oxide composition" as used herein means the case where the total weight of the oxide substances when oxides, complex salts, hydroxides, etc. used as raw materials for the composition of the optical glass of the present invention are decomposed into oxides during melting is taken as 100%.

[0025] Specifically, the numerical ranges described in this specification include upper and lower limit values, and "above" and "below" include the end point values, as well as all integers and fractions included in the range, and are not limited to the specific values described when the range is limited. What is referred to as "and / or" in this specification is inclusive. For example, "A and / or B" means only A, only B, or both A and B.

[0026] <Essential Components and Optional Components> SiO2 and B2O3 are the main network - forming components of the glass of the present invention. The strong structure formed by these two network - forming components is the basis for realizing high transmittance of ultraviolet light and excellent chemical stability. When the content of SiO2 is less than 55%, the glass transmittance at 365 nm is low, and it is difficult to reach 99.0% or more. This is fatal for ultraviolet optical systems with long optical paths such as photolithography lenses and exposure machine prisms, which have high illuminance requirements. Therefore, the lower limit of the content of SiO2 is 55%, preferably 56%, more preferably 57%. When the content of SiO2 exceeds 70%, it becomes difficult for the refractive index of the glass to meet the design requirements, and the glass needs to be melted at a higher temperature. Under a higher melting temperature, the erosion of the glass melt to the crucible expands exponentially, and the content of ions with strong absorption effects in the ultraviolet band, such as iron (Fe) ions and platinum (Pt) ions, increases rapidly, and instead, the transmittance of ultraviolet light, especially the transmittance at 365 nm, decreases rapidly. Also, when the content of SiO2 is too high, the high - temperature viscosity of the glass becomes too large, and it becomes difficult for the optical uniformity, bubble degree, stripe, etc. to meet the design requirements. Therefore, the upper limit of the content of SiO2 is 70%, preferably 68%, more preferably 67%.

[0027] An appropriate amount of B2O3 can increase the refractive index of the glass, strengthen the structure of the glass, and improve the ultraviolet - irradiation resistance performance of the glass. When the content of B2O3 exceeds 18%, the erosion of the glass melt to the crucible increases rapidly, and the transmittance of ultraviolet light decreases rapidly. When the content of B2O3 is less than 2%, it becomes difficult to melt the glass. Therefore, the content of B2O3 is 2 - 18%, preferably 4 - 16%, more preferably 5 - 15%.

[0028] Al2O3 can increase the compactness of the internal structure of the glass and improve the ultraviolet transmittance and chemical stability of the glass. However, when its content exceeds 5%, stones are likely to occur inside the glass, and the internal quality of the glass decreases. Therefore, the content of Al2O3 is limited to 5% or less, preferably 4% or less, more preferably 3% or less.

[0029] Any of SiO2, B2O3, and Al2O3 can form a glass network. As a result of a large number of experimental studies by the inventors, it has been found that when the above three types of network-forming components coexist, the structure of the glass changes complexly, and the properties such as the high-temperature viscosity and chemical stability of the glass also change. In some embodiments, by controlling the value of (B2O3 + Al2O3) / SiO2 within 0.05 to 0.4, the glass can have excellent chemical stability and prevent the high-temperature viscosity from increasing. Therefore, the value of (B2O3 + Al2O3) / SiO2 is preferably 0.05 to 0.4, more preferably 0.08 to 0.35, and even more preferably 0.1 to 0.3.

[0030] BaO, SrO, CaO, and MgO are alkaline earth metal oxides. Conventional barium crown glass contains a large amount of BaO to increase the refractive index of the glass, which is also the origin of the variety of barium crown glass. As a result of repeated research, the inventors found that although alkaline earth metal oxides can improve the refractive index and stability of the glass, a glass structure with high tightness cannot be obtained, and the ultraviolet transmittance and chemical stability of the glass are relatively low. In the glass of the present invention, when the total content of alkaline earth metal oxides BaO + SrO + CaO + MgO exceeds 15%, the ultraviolet transmittance of the glass significantly decreases. Therefore, the total content of alkaline earth metal oxides BaO + SrO + CaO + MgO in the present invention is 0 to 15%. Also, when BaO + SrO + CaO + MgO is less than 1%, the effect of improving the stability of the glass is not significant, and the crystallization tendency of the glass increases, which is very disadvantageous for the forming of large-sized glass (for example, glass with a width of 330 mm or more and a thickness of 30 mm or more). Therefore, the total content of alkaline earth metal oxides BaO + SrO + CaO + MgO in the present invention is preferably 1 to 15%, more preferably 1.5 to 10%, and even more preferably 1.5 to 8%. Regarding the selection of the type of alkaline earth metal oxides, preferably BaO and / or SrO are most advantageous for improving the glass stability, more preferably BaO, and even more preferably not containing CaO and / or MgO.

[0031] Conventional barium crown glass improves the refractive index of the glass by using a large amount of alkaline earth metal oxides. As a result of a large number of experimental studies, the inventors found that in some embodiments, when the value of (BaO + SrO + CaO + MgO) / SiO2 exceeds 0.25, the refractive index of the glass is likely to meet the design requirements, but the glass structure is destroyed, the impurity level increases, and the ultraviolet transmittance rapidly decreases. Therefore, the value of (BaO + SrO + CaO + MgO) / SiO2 in the present invention is preferably 0.25 or less, more preferably 0.2 or less, still more preferably 0.15 or less, and even more preferably 0.1 or less. Also, by setting the (BaO + SrO + CaO + MgO) / SiO2 value to 0.01 or more, it is possible to prevent a decrease in the stability and chemical stability of the glass. Therefore, the (BaO + SrO + CaO + MgO) / SiO2 value is preferably 0.01 or more, more preferably 0.02 or more.

[0032] By adding an appropriate amount of ZnO, the network structure of the glass can be strengthened, and the refractive index and ultraviolet transmittance of the glass can be improved. When the ZnO content exceeds 20%, the phase separation tendency of the glass increases, the ultraviolet transmittance conversely decreases, and it becomes difficult for the stripe to meet the design requirements. Also, when the ZnO content is less than 1%, the effect of increasing the ultraviolet transmittance of the glass is not significant, the surface tension of the glass increases, it is difficult to remove air bubbles, and the bubble degree becomes difficult to meet the design requirements. Therefore, the ZnO content is 1 to 20%, preferably 2 to 16%, and more preferably 3 to 12%.

[0033] La2O3, Gd2O3, and Y2O3 are high refractive index and low dispersion oxides. By adding them to glass, the refractive index of the glass can be rapidly increased, and the dispersion of the glass can be adjusted. As a result of extensive research by the inventors, it has been found that all of La2O3, Gd2O3, and Y2O3 have strong aggregation in the glass, can enhance the stability of the glass structure, and can increase the ultraviolet transmittance of the glass while increasing the refractive index. In addition, by adding an appropriate amount, the ultraviolet irradiation resistance of the glass can be enhanced, the viscosity of the glass can be lowered, making the melting, clarification, and forming of the glass easier, and it is advantageous for obtaining higher optical uniformity, bubble degree, and stripes. However, if the content of La2O3, Gd2O3, or Y2O3 is too high, the glass is particularly prone to crystallization, and glass-ceramics may also occur. Therefore, the total content of La2O3, Gd2O3, and Y2O3 in the present invention, La2O3 + Y2O3 + Gd2O3, is 4 to 30%, preferably 5 to 20%, more preferably 7 to 15%.

[0034] As a result of extensive experimental research by the inventors, it has been found that in terms of improving the ultraviolet transmittance, La2O3 is superior to Y2O3, Y2O3 is superior to Gd2O3, and in terms of improving the ultraviolet irradiation resistance of the glass, La2O3 is slightly superior to Gd2O3, and Gd2O3 is superior to Y2O3. Therefore, considering the performance of the glass such as ultraviolet transmittance, ultraviolet irradiation resistance, and crystallization resistance, the content of La2O3 in the present invention is preferably 4 to 25%, more preferably 6 to 20%, even more preferably 7 to 14%, the content of Y2O3 is preferably 0 to 10%, more preferably 0 to 8%, even more preferably 0 to 5%, and the content of Gd2O3 is preferably 0 to 8%, more preferably 0 to 7%, even more preferably 0 to 5%.

[0035] As a result of a large number of experimental studies, the inventors have found that in some embodiments, when the value of (La2O3 + Y2O3 + Gd2O3) / SiO2 exceeds 0.35, the stability and crystallization resistance of the glass decrease, and ceramics may be formed during the flow of the glass melt. When the value of (La2O3 + Y2O3 + Gd2O3) / SiO2 is less than 0.07, the viscosity of the glass at 1400 °C exceeds 400 poises. When producing at a high viscosity, it is difficult to meet the design requirements for the bubble degree and stripes, and it is also difficult to achieve the design requirements for the ultraviolet transmittance of the glass. More importantly, the structure of the glass tends to relax, and the ultraviolet irradiation resistance of the glass tends to decrease. Therefore, preferably, the value of (La2O3 + Y2O3 + Gd2O3) / SiO2 is 0.07 to 0.35, more preferably, the value of (La2O3 + Y2O3 + Gd2O3) / SiO2 is 0.08 to 0.3, and even more preferably, the value of (La2O3 + Y2O3 + Gd2O3) / SiO2 is 0.1 to 0.25.

[0036] In some embodiments of the present invention, when the value of (La2O3 + Y2O3 + Gd2O3) / B2O3 exceeds 6.0, the crystallization resistance of the glass decreases. When the value of (La2O3 + Y2O3 + Gd2O3) / B2O3 is less than 0.3, the chemical stability of the glass deteriorates and the ultraviolet transmittance decreases. Therefore, preferably, the value of (La2O3 + Y2O3 + Gd2O3) / B2O3 is 0.3 to 6.0, more preferably 0.4 to 5.0, and even more preferably 0.5 to 3.0.

[0037] Ta2O5, Nb2O5, TiO2, and ZrO2 are high refractive index and high dispersion oxides. By adding them to glass, the ultraviolet irradiation resistance performance of the glass can be enhanced, and at the same time, the refractive index and dispersion of the glass can be increased. In the present invention, the total content of Ta2O5, Nb2O5, TiO2, and ZrO2, Ta2O5 + Nb2O5 + TiO2 + ZrO2, is set to 0.5% or more to obtain the above effects. Preferably, Ta2O5 + Nb2O5 + TiO2 + ZrO2 is 1% or more, more preferably 2% or more. Also, Ta2O5, Nb2O5, TiO2, and ZrO2 have the effect of reducing the ultraviolet transmittance in the glass. When the total content of Ta2O5, Nb2O5, TiO2, and ZrO2, Ta2O5 + Nb2O5 + TiO2 + ZrO2, exceeds 20%, it becomes difficult for the ultraviolet transmittance of the glass, especially the transmittance at 365 nm, to meet the design requirements. Therefore, Ta2O5 + Nb2O5 + TiO2 + ZrO2 is 20% or less, preferably 15% or less, more preferably 10% or less.

[0038] In the glass production process, when the upper limit temperature of glass crystallization exceeds 1300 °C, the glass liquid is likely to clog at each connection stage of the melting furnace, and the transmittance, internal quality, and stripes of the glass cannot meet the design requirements. As a result of a large amount of experimental research by the inventors, in some embodiments, by controlling the ratio of the total content of La2O3, Y2O3, and Gd2O3, La2O3 + Y2O3 + Gd2O3, to the total content of Ta2O5, Nb2O5, TiO2, and ZrO2, Ta2O5 + Nb2O5 + TiO2 + ZrO2, within 1.0 to 13.0, preferably within 2.0 to 10.0, more preferably within 3.0 to 7.0, the upper limit temperature of glass crystallization can be lowered, and at the same time, the ultraviolet light transmittance and irradiation resistance performance of the glass can be enhanced.

[0039] In some embodiments, by controlling the value of La2O3 / Nb2O5 within 3.5 to 15.0, preferably within 5.0 to 14.0, more preferably within 7.0 to 13.5, the ultraviolet irradiation resistance performance and stability of the glass are optimized.

[0040] Li2O, Na2O, and K2O are alkali metal oxides. In the present invention, they can lower the high-temperature viscosity of the glass, provide free oxygen to strengthen the glass network structure, and increase the ultraviolet transmittance of the glass. From the perspective of the strengthening effect on the glass network structure, when the content is reasonable, the strengthening effects of Na2O and K2O are the strongest. However, since K2O has a stronger ability to reduce the chemical stability of the glass than Na2O, it is necessary to more strictly control the content of K2O. If the contents of Na2O and K2O are too high, a large amount of glass raw materials will volatilize during the production process, making it difficult to meet the design requirements regarding the stability of the refractive index and also reducing the stability of the glass. Therefore, preferably, the content of Na2O is 2 - 15%, more preferably 4 - 14%, even more preferably 5 - 13%, and preferably the content of K2O is 0 - 8%, more preferably 1 - 6%, even more preferably 2 - 5%.

[0041] Li2O, which is an alkali metal oxide, has the highest ability to lower the high-temperature viscosity. When the high-temperature viscosity does not meet the design requirements, a small amount of Li2O can be added. However, when its content exceeds 5%, the crystallization of the glass is serious, the forming viscosity of the glass is small, and it is difficult to meet the forming requirements for a thick size. Therefore, the content of Li2O is limited to 5% or less, preferably 4% or less, more preferably 3% or less, and even more preferably it does not contain Li2O.

[0042] In some embodiments of the present invention, when the total content of Li2O, Na2O, and K2O, Li2O + Na2O + K2O, is less than 3%, the temperature coefficient of the refractive index of the glass rapidly increases. The refractive index of the glass lens changes more significantly within the same temperature change range, and the imaging quality of the optical system rapidly deteriorates. On the other hand, the glass cannot achieve good bubble degree. When Li2O + Na2O + K2O exceeds 15%, the stability of the glass rapidly decreases, the structure of the glass loosens, and the ultraviolet irradiation resistance performance deteriorates. Therefore, preferably, Li2O + Na2O + K2O is 3 - 15%, more preferably 5 - 14%, even more preferably 6 - 13%.

[0043] A small amount of F (fluorine) can increase the ultraviolet transmittance and ultraviolet irradiation resistance of the glass. When the F content exceeds 3%, it will be greatly volatilized during the glass melting process, the refractive index of the glass becomes unstable, it is difficult for the optical uniformity of the glass to meet the design requirements, and it will also cause harm to the production environment and the health of operators. Therefore, the F content is controlled to be 3% or less, preferably 2% or less, more preferably 1% or less. In some embodiments, if there is room for the ultraviolet transmittance and ultraviolet irradiation resistance performance of the glass, it is even more preferable that F is not contained.

[0044] In the present invention, by adding one or more components of Sb2O3, SnO, SnO2, CeO2, Cl, Br as fining agents in an amount of 0-1%, the fining effect of the glass can be enhanced. Preferably, the content of the fining agent is 0-0.8%, more preferably 0-0.5%. Preferably, Sb2O3 is added as a fining agent. When the content of Sb2O3 exceeds 1%, the ultraviolet transmittance of the glass decreases.

[0045] <Components that should not be included> 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, will color the glass, absorb specific wavelengths in the visible light region, and weaken the visible light transmission effect of the present invention. Therefore, for optical glass that requires a specific wavelength transmittance in the visible light region, it is preferably not actually contained.

[0046] Oxides of Th, Cd, Tl, Os, Be, and Se have a tendency to be restricted in use as harmful chemical substances in recent years. From the glass manufacturing process to the processing process and the disposal of the finished product, efforts for environmental protection are required. Therefore, when emphasizing the impact on the environment, it is preferably not to contain them except for inevitable contamination. This makes the optical glass not actually contain substances that pollute the environment. Therefore, the optical glass of the present invention can be manufactured, processed, and discarded without taking special environmental measures.

[0047] For environmental considerations, the optical glass of the present invention preferably does not contain As2O3 and PbO.

[0048] The terms "not added", "not contained", and "0%" described in this specification mean that this component was not intentionally added as a raw material for the glass of the present invention. However, as raw materials and / or equipment for manufacturing glass, impurities and components that were not intentionally added may be present in trace amounts or small amounts in the final glass, and these are also the subject of the patent of the present invention.

[0049] The characteristics of the optical glass of the present invention will be described below.

[0050] <Refractive Index and Abbe Number> The refractive index (n d ) and Abbe number (ν d ) of the optical glass are tested according to the methods specified in GB / T 7962.1-2010.

[0051] In some embodiments, the lower limit of the refractive index (n d ) of the optical glass of the present invention is 1.51, preferably the lower limit is 1.52, more preferably the lower limit is 1.53. In some embodiments, the upper limit of the refractive index (n d ) of the optical glass of the present invention is 1.58, preferably the upper limit is 1.57, more preferably the upper limit is 1.56. In some embodiments, the lower limit of the Abbe number (ν d ) of the optical glass of the present invention is 55, preferably the lower limit is 56, more preferably the lower limit is 57. In some embodiments, the upper limit of the Abbe number (ν d ) of the optical glass of the present invention is 65, preferably the upper limit is 63, more preferably the upper limit is 60.

[0052] <Water Resistance Stability> The water resistance stability (D W ) (powder method) of the optical glass is tested by the method specified in GB / T 17129.

[0053] 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.

[0054] <Acid resistance stability> The acid resistance stability (D A ) (powder method) of the optical glass is tested by the method specified in GB / T 17129. In some embodiments, the acid resistance stability (D A ) of the optical glass of the present invention is Class 3 or higher, preferably Class 2 or higher, more preferably Class 1.

[0055] <Refractive index temperature coefficient> The refractive index temperature coefficient (dn / dt) of the optical glass is measured according to the method specified in "GB / T 7962.4-2010" for the refractive index temperature coefficient (d-line dn / dt relative (10 -6 / °C)) of the optical glass within the range of 40 to 60 °C. In some embodiments, the refractive index temperature coefficient (dn / dt) of the optical glass of the present invention is 8.0×10 -6 / °C or less, preferably 7.0×10 -6 / °C or less, more preferably 6.0×10 -6 / °C or less.

[0056] <Internal transmittance τ at 365 nm 365nm > The ultraviolet transmittance of the optical glass of the present invention is expressed by the internal transmittance at 365 nm. The internal transmittance at 365 nm (τ 365nm ) is measured according to the method specified in "GB / T7962.12-2010", and the thickness of the glass sample is 10 mm.

[0057] In some embodiments, the internal transmittance at 365 nm (τ 365nm ) of the optical glass of the present invention is 99.0% or more, preferably 99.2% or more, more preferably 99.4% or more, and still more preferably 99.5% or more.

[0058] <Internal transmittance UV irradiation attenuation performance at 365 nm> The UV irradiation resistance performance of the optical glass is Δτ 365nm which is shown as, that is, the internal transmittance UV irradiation attenuation performance at 365 nm, and the test method is as follows. According to the method specified in 'GB / T7962.12 - 2010', the original internal transmittance τ 365nm-1 of the sample at 365 nm is measured. Next, it is irradiated using a high - pressure mercury lamp, and the power density on the glass surface is 1 W / cm 2 . After 2 - hour irradiation, the internal transmittance τ 365nm-2 at 365 nm is re - measured according to the method specified in 'GB / T7962.12 - 2010'. The difference τ 365nm-1 - τ 365nm-2 between the two measured values is, that is, the attenuation of the glass at this wavelength, and the thickness of the glass sample is 10 mm.

[0059] In some embodiments, the internal transmittance UV irradiation attenuation performance (Δτ 365nm ) of the optical glass of the present invention at 365 nm is 5.0% or less, preferably 2.0% or less, more preferably 1.0% or less.

[0060] <Crystallization upper - limit temperature> The crystallization resistance of the glass is measured using the temperature - gradient furnace method. The glass is made into a sample of 180 mm×10 mm×10 mm, the side surface is polished, and it is placed in a furnace with a temperature gradient (10℃ / cm). The temperature in the highest - temperature region is raised to 1400℃, held for 4 hours, then taken out and naturally cooled to room temperature. The crystallization situation of the glass is observed under a microscope, and the highest temperature when crystals are confirmed is defined as the crystallization upper - limit temperature of the glass.

[0061] In some embodiments, the crystallization upper - limit temperature of the optical glass of the present invention is 1300℃ or lower, preferably 1280℃ or lower, more preferably 1250℃ or lower, and even more preferably 1230℃ or lower.

[0062] <Bubble degree> The bubble degree of the optical glass is measured and classified according to the method specified in 'GB / T 7962.8-2010'.

[0063] In some embodiments, the bubble degree of the optical glass of the present invention is grade A or above, preferably grade A0 or above, more preferably grade A 00 grade.

[0064] <Stripe> The stripe test method for the optical glass is as follows: Using a stripe meter composed of a point light source and a lens, compare the standard sample from the direction where the stripes are most visible, and it is divided into four grades according to the regulations in Table 1.

[0065]

Table 1

[0066] In some embodiments, the stripe of the optical glass of the present invention is grade C or above, preferably grade B or above.

[0067] <Optical uniformity> The optical uniformity of the optical glass is represented by the maximum value Δn of the refractive index deviation of each part of a single glass sample d and is tested according to the test method specified in 'GB / T 7962.2-2010'.

[0068] In some embodiments, the Δn d value of the optical glass of the present invention is 5×10 -6 or less, preferably 3×10 -6 or less, more preferably 2×10 -6 or less.

[0069] [Manufacturing method of optical glass] The manufacturing method of the optical glass of the present invention is as follows: General raw materials such as carbonates, nitrates, sulfates, oxides, and hydroxides are manufactured by conventional processes and mixed by conventional methods. Then, the prepared furnace materials are put into a melting furnace (such as a platinum or quartz crucible) at 1200°C to 1600°C and melted. Thereafter, clarification, stirring, and homogenization are performed to obtain a homogeneous molten glass without bubbles and undissolved substances. This molten glass is then put into a mold for casting and annealing. Those skilled in the art can appropriately select raw materials, manufacturing methods, and process parameters according to actual requirements.

[0070] [Glass preform and optical element] A glass preform can be manufactured from the produced optical glass using a press forming method such as direct dropping forming, grinding, or hot press forming. That is, the molten optical glass can be manufactured into a precise glass preform by direct precision dropping forming, the glass preform can be manufactured by machining such as grinding and polishing, a preform blank for press forming can be produced using optical glass, and this preform blank can be hot pressed and polished to produce a glass preform. It should be noted that it is to be explained that the manufacturing means of the optical preform is not limited to the above means.

[0071] 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 blank from the optical glass of the present invention and perform hot press forming, precision press forming, etc. using this blank to produce optical elements such as lenses and prisms. Both the optical preform and the optical element of the present invention are formed from the optical glass of the present invention. The optical preform of the present invention has excellent characteristics possessed by the optical glass, and the optical element of the present invention has excellent characteristics possessed by the optical glass, and can provide various optical elements with high optical value such as lenses and prisms.

[0072] 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.

[0073] [Optical device] The optical element fabricated with the optical glass of the present invention can be used in the manufacture of optical devices such as photographic devices, imaging devices, projection devices, display devices, photolithography devices, in-vehicle devices, and monitoring devices.

Example

[0074] <Example of optical glass> To more clearly illustrate the technical solution of the present invention, the following non-limiting examples are provided. In this example, using the manufacturing method of the above optical glass, optical glasses having the components shown in Tables 2 to 3 are obtained. Also, the characteristics of each glass are measured by the test method described in the present invention, and the results are shown in Tables 2 to 3.

[0075]

Table 2

[0076]

Table 3

[0077] <Example of glass preform> The glasses obtained in Examples 1 to 13 of the optical glass are used to manufacture preforms such as various lenses (e.g., concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, and plano-concave lenses) and prisms using polishing means or press forming means such as reheat press forming and precision press forming.

[0078] <Example of optical element> 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 the desired values.

[0079] 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.

[0080] <Example of optical device> The optical elements manufactured in the examples of the above optical elements can be used 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 by forming optical components or optical components using one or more optical elements according to optical design.

Claims

1. Optical glass containing the following components by weight percentage: SiO 2 : 55 - 70%, B 2 O 3 : 2 - 18%, ZnO: 1 - 20%, La 2 O 3 +Y 2 O 3 +Gd 2 O 3 : 4 - 30%, Ta 2 O 5 +Nb 2 O 5 +TiO 2 +ZrO 2 : 0.5 - 20%, Li 2 O + Na 2 O + K 2 O: 3 - 15%, (La 2 O 3 +Y 2 O 3 +Gd 2 O 3 ) / (Ta 2 O 5 +Nb 2 O 5 +TiO 2 +ZrO 2 ) is 1.0 - 13.0, BaO + SrO + CaO + MgO: 0 - 9.2%, La 2 O 3 / Nb 2 O 5 is 3.5 - 15.

0.

2. The optical glass according to claim 1, further comprising the following components by weight %: Al 2 O 3 : 0 to 5%, and / or F: 0 to 3%, and / or fining agent: 0 to 1%, the fining agent being Sb 2 O 3 , SnO, SnO 2 , CeO 2 , one or more of Cl, Br.

3. Optical glass containing the following components by weight percentage: SiO 2 : 55 to 70%; B 2 O 3 : 2 to 18%, ZnO: 1 to 20%, La 2 O 3 +Y 2 O 3 +Gd 2 O 3 : 4 to 30%, Ta 2 O 5 +Nb 2 O 5 +TiO 2 +ZrO 2 : 0.5 to 20%, Li 2 O + Na 2 O + K 2 O: 3 to 15%, BaO + SrO + CaO + MgO: 0 to 9.2%, Al 2 O 3 : 0 to 5%, F: 0 to 3%, fining agent: 0 to 1%, La 2 O 3 / Nb 2 O 5 is 3.5 to 15.0, and the fining agent is Sb 2 O 3 、SnO、SnO 2 、CeO 2 、Cl, Br, or one or more of them.

4. The optical glass according to claim 1, comprising the following components by weight%: (La 2 O 3 +Y 2 O 3 +Gd 2 O 3 ) / (Ta 2 O 5 +Nb 2 O 5 +TiO 2 +ZrO 2 ) is 1.0 to 13.

0.

5. An optical glass according to any one of Claims 1 to 3, comprising the following components by weight %, provided that it satisfies one or more of the following 1) to 5): 1) (La 2 O 3 +Y 2 O 3 +Gd 2 O 3 ) / (Ta 2 O 5 +Nb 2 O 5 +TiO 2 +ZrO 2 ) is 2.0 to 10.0; 2) (La 2 O 3 +Y 2 O 3 +Gd 2 O 3 ) / SiO 2 is 0.07 to 0.35; 3) (B 2 O 3 + Al 2 O 3 ) / SiO 2 is 0.05 to 0.4; 4) (BaO + SrO + CaO + MgO) / SiO 2 is 0.01 to 0.25; 5) (La 2 O 3 + Y 2 O 3 + Gd 2 O 3 ) / B 2 O 3 is 0.3 to 6.

0.

6. An optical glass according to any one of Claims 1 to 3, comprising the following components by weight %, provided that it satisfies one or more of the following 1) to 6): 1) (La 2 O 3 +Y 2 O 3 +Gd 2 O 3 ) / (Ta 2 O 5 +Nb 2 O 5 +TiO 2 +ZrO 2 ) is 3.0 to 7.0; 2) La 2 O 3 / Nb 2 O 5 is 5.0 to 14.0; 3) (La 2 O 3 +Y 2 O 3 +Gd 2 O 3 ) / SiO 2 is 0.08 to 0.3; 4) (B 2 O 3 + Al 2 O 3 ) / SiO 2 is 0.08 to 0.35; 5) (BaO + SrO + CaO + MgO) / SiO 2 is 0.01 to 0.2; 6) (La 2 O 3 +Y 2 O 3 +Gd 2 O 3 ) / B 2 O 3 is 0.4 to 5.

0.

7. An optical glass according to any one of Claims 1 to 3, comprising the following components by weight %, provided that it satisfies one or more of the following 1) to 5): 1) La 2 O 3 / Nb 2 O 5 is 7.0 to 13.5; 2) (La 2 O 3 +Y 2 O 3 +Gd 2 O 3 ) / SiO 2 is 0.1 to 0.25; 3) (B 2 O 3 + Al 2 O 3 ) / SiO 2 is 0.1 to 0.3; 4) (BaO + SrO + CaO + MgO) / SiO 2 is from 0.02 to 0.15; 5) (La 2 O 3 +Y 2 O 3 +Gd 2 O 3 ) / B 2 O 3 is 0.5 to 3.

0.

8. The optical glass according to any one of claims 1 to 3, comprising the following components in % by weight: (BaO + SrO + CaO + MgO) / SiO 2 is from 0.02 to 0.

1.

9. The optical glass according to any one of claims 1 to 3, comprising the following components by weight%: SiO 2 : 56 to 68%, and / or B 2 O 3 : 4 to 16%, and / or ZnO: 2 to 16%, and / or La 2 O 3 +Y 2 O 3 +Gd 2 O 3 : 5 to 20%, and / or Ta 2 O 5 +Nb 2 O 5 +TiO 2 +ZrO 2 : 1 to 15%, and / or Li 2 O + Na 2 O + K 2 O: 5 to 14%, and / or BaO + SrO + CaO + MgO: 1 to 9.2%, and / or Al 2 O 3 : 0 to 4%, and / or F: 0 to 2%, and / or fining agent: 0 to 0.8%, the fining agent being Sb 2 O 3 、SnO, SnO 2 、CeO 2 、Cl, Br, or one or more of them.

10. The optical glass according to any one of claims 1 to 3, comprising the following components by weight%: SiO 2 : 57 to 67%, and / or B 2 O 3 : 5 to 15%, and / or ZnO: 3 to 12%, and / or La 2 O 3 +Y 2 O 3 +Gd 2 O 3 : 7 to 15%, and / or Ta 2 O 5 +Nb 2 O 5 +TiO 2 +ZrO 2 : 2 to 10%, and / or Li 2 O + Na 2 O + K 2 O: 6 to 13%, and / or BaO + SrO + CaO + MgO: 1.5 to 8%, and / or Al 2 O 3 : 0 to 3%, and / or F: 0 to 1%, and / or fining agent: 0 to 0.5%, the fining agent being Sb 2 O 3 、SnO、SnO 2 、CeO 2 、Cl, Br, or one or more of them.

11. The optical glass according to any one of claims 1 to 3, comprising the following components in % by weight: La 2 O 3 : 4 to 25%, and / or Gd 2 O 3 : 0 to 8%, and / or Y 2 O 3 : 0 to 10%, and / or Na 2 O: 2 to 15%, and / or K 2 O: 0 to 8%, and / or Li 2 O: 0 to 5%.

12. The optical glass according to any one of claims 1 to 3, comprising the following components by weight%: La 2 O 3 : 7 to 14%, and / or Gd 2 O 3 : 0 to 5%, and / or Y 2 O 3 : 0 to 5%, and / or Na 2 O: 5 to 13%, and / or K 2 O: 2 to 5%, and / or Li 2 O: 0 to 3%.

13. The optical glass according to any one of claims 1 to 3, wherein the component does not contain F, and / or does not contain MgO, and / or does not contain CaO, and / or does not contain Li 2 2O.

14. The refractive index n of the optical glass d is 1.51 to 1.58, and / or the Abbe number v d is 55 to 65, and the optical glass according to any one of claims 1 to 3.

15. The refractive index n of the optical glass d is 1.53 to 1.56, and / or the Abbe number v d is 57 to 60, and the optical glass according to any one of claims 1 to 3.

16. The τ of the optical glass 365nm is 99.0% or more, and / or Δτ 365nm is 5.0% or less, and / or the hydrolysis stability D W is Class 2 or more, and / or the acid resistance stability D A is Class 3 or more, and / or the refractive index temperature coefficient dn / dt is 8.0×10 -6 / °C or less, and / or the crystallization upper limit temperature is 1300°C or less, and / or the bubble degree is Class A or more, and / or the stripe is Class C or more, and / or Δn d value is 5×10 -6 or less. The optical glass according to any one of claims 1 to 3

17. The τ of the optical glass 365nm is 99.5% or more, and / or Δτ 365nm is 1.0% or less, and / or the water resistance stability D W is Class 1, and / or the acid resistance stability D A is Class 2 or higher, and / or the refractive index temperature coefficient dn / dt is 6.0×10 -6 / °C or less, and / or the crystallization upper limit temperature is 1230°C or less, and / or the bubble degree is Grade A 00 and / or the stripe is Grade B or higher, and / or Δn d value is 2×10 -6 or less. The optical glass according to any one of claims 1 to 3

18. A glass preform manufactured from the optical glass according to any one of Claims 1 to 17.

19. An optical element manufactured using the optical glass according to any one of Claims 1 to 17, or manufactured using the glass preform according to Claim 18.

20. An optical device comprising the optical glass according to any one of Claims 1 to 17, and / or an optical device comprising the optical element according to Claim 19.

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