TWI783603B - Optical glass, glass preforms, optical components and optical instruments - Google Patents

Abstract

The invention provides an optical glass, the components of which are represented by weight percentage, including: B ₂ O ₃ : 8-20%; La ₂ O ₃ : 21-40%; Gd ₂ O ₃ : 6-20%; ZrO ₂ : 1~10%; ZnO: 7~20%; WO ₃ : 8~20%; TiO ₂ : greater than 0 but less than or equal to 10%, where (WO ₃ +ZnO)/(La ₂ O ₃ +TiO ₂ +ZrO ₂ ) 0.3~1.5. Through reasonable component design, the optical glass obtained by the invention has lower transition temperature and thermal expansion coefficient, and is suitable for precision molding.

Description

Optical glass, glass preforms, optical components and optical instruments

The invention relates to an optical glass, in particular to an optical glass with a low thermal expansion coefficient and high refractive index suitable for precision molding, as well as a glass preform and an optical element made thereof.

Optical glass is a glass material used to manufacture lenses, prisms, mirrors and windows in optical instruments or mechanical systems. At present, the mainstream method of manufacturing optical glass into optical components is precision molding (including direct pressing method and secondary pressing method). Lenses manufactured by precision molding technology usually do not need to be ground and polished, thereby reducing the consumption of raw materials. The cost of manpower and material resources is reduced, and environmental pollution is reduced. This technology can produce optical components in large quantities at low cost. The so-called precision molding is to mold a glass preform with a high-precision mold with a predetermined product shape under a certain temperature and pressure, so as to obtain a glass product with the final product shape and optical function. Various optical glass products such as spherical lenses, aspheric lenses, prisms and diffraction gratings can be manufactured through precision molding technology.

When performing precision compression molding, in order to replicate the high-precision mold surface on the finished glass product, it is necessary to pressurize the glass preform at high temperature (usually above the glass transition temperature of 20~60°C). At this time, the forming mold is under high temperature and pressure Under the environment, even in the protective gas, the surface of the mold is easily oxidized and corroded. In order to prolong the life of the mold and suppress the damage to the mold in the high temperature environment, it is necessary to reduce the molding temperature. Therefore, the transition temperature (Tg) of the glass material used for molding needs to be as low as possible.

With the advancement of science and technology, the continuous update of optoelectronic information products, the demand for optical glass The quantity is also increasing, and at the same time, higher requirements are put forward for the performance of optical glass. For example, due to the large thermal expansion coefficient of optical glass, it is easy to cause cracks during thermal processing, which reduces the yield of glass components; at the same time, it also leads to poor thermal shock resistance of optical glass.

Under the same radius of curvature, glass with a higher refractive index can obtain a larger imaging field of view. With the development trend of miniaturization of optical devices, the demand for glass with a higher refractive index is becoming more and more obvious.

The technical problem to be solved by the present invention is to provide a high-refractive-index optical glass with a low coefficient of thermal expansion and suitable for precision molding.

The technical scheme that the present invention solves technical problem adopts is:

(1) Optical glass, the composition of which is expressed in weight percent, containing: B ₂ O ₃ : 8~20%; La ₂ O ₃ : 21~40%; Gd ₂ O ₃ : 6~20%; ZrO ₂ : 1 ~10%; ZnO: 7~20%; WO ₃ : 8~20%; TiO ₂ : greater than 0 but less than or equal to 10%, where (WO ₃ +ZnO)/(La ₂ O ₃ +TiO ₂ +ZrO ₂ ) is 0.3~1.5.

(2) The optical glass according to (1), the composition of which is expressed in weight percent, further contains: SiO ₂ : 0~9%; and/or Y ₂ O ₃ : 0~10%; and/or Yb ₂ O ₃ : 0~10%; and/or Nb ₂ O ₅ : 0~8%; and/or Rn ₂ O: 0~10%; and/or RO: 0~10%; and/or Al ₂ O ₃ : 0~5%; and/or Ta ₂ O ₅ : 0~5%; and/or clarifying agent: 0~1%, the Rn ₂ O is one of Li ₂ O, Na ₂ O, K ₂ O or more, RO is one or more of MgO, CaO, SrO, and BaO, and the clarifying agent is one or more of Sb ₂ O ₃ , SnO ₂ , SnO, and CeO ₂ .

(3) Optical glass, containing B ₂ O ₃ , La ₂ O ₃ , Gd ₂ O ₃ , ZrO ₂ , ZnO, WO ₃ and TiO ₂ as essential components, and its components are expressed in weight percent, where (WO ₃ + ZnO)/(La ₂ O ₃ +TiO ₂ +ZrO ₂ ) is 0.3~1.5, the refractive index n _d of the optical glass is 1.85~1.91, the Abbe number ν _d is 32~38.5, and the coefficient of thermal expansion α is _{100/300 °C} is 100×10 ^-7 /K or less.

(4) The optical glass according to (3), the components of which are expressed in weight percent, containing: B ₂ O ₃ : 8-20%; and/or La ₂ O ₃ : 21-40%; and/or Gd ₂ O ₃ : 6~20%; and/or ZrO ₂ : 1~10%; and/or ZnO: 7~20%; and/or WO ₃ : 8~20%; and/or TiO ₂ : greater than 0 but Less than or equal to 10%; and/or SiO ₂ : 0~9%; and/or Y ₂ O ₃ : 0~10%; and/or Yb ₂ O ₃ : 0~10%; and/or Nb ₂ O ₅ : 0~8%; and/or Rn ₂ O: 0~10%; and/or RO: 0~10%; and/or Al ₂ O ₃ : 0~5%; and/or Ta ₂ O ₅ : 0 ~5%; and/or clarifying agent: 0~1%, the Rn ₂ O is one or more of Li ₂ O, Na ₂ O, K ₂ O, and RO is one of MgO, CaO, SrO, BaO or more, and the clarifying agent is one or more of Sb ₂ O ₃ , SnO ₂ , SnO, and CeO ₂ .

(5) Optical glass, the composition of which is represented by weight percentage, consisting of B ₂ O ₃ : 8~20%; La ₂ O ₃ : 21~40%; Gd ₂ O ₃ : 6~20%; ZrO ₂ : 1~ 10%; ZnO: 7~20%; WO ₃ : 8~20%; TiO ₂ : greater than 0 but less than or equal to 10%; SiO ₂ : 0~9%; Y ₂ O ₃ : 0~10%; Yb ₂ O ₃ : 0~10%; Nb ₂ O ₅ : 0~8%; Rn ₂ O : 0~10%; RO: 0~10%; Al ₂ O ₃ : 0~5%; Ta ₂ O ₅ : 0 ~5%; clarifying agent: 0~1% composition, where (WO ₃ +ZnO)/(La ₂ O ₃ +TiO ₂ +ZrO ₂ ) is 0.3~1.5, and the Rn ₂ O is Li ₂ O, Na ₂ One or more of O and K ₂ O, RO is one or more of MgO, CaO, SrO, and BaO, and the clarifying agent is one or more of Sb ₂ O ₃ , SnO ₂ , SnO, and CeO ₂ .

(6) The optical glass according to any one of (1) to (5), the components of which are expressed in weight percent and satisfy at least one of the following nine conditions: 1) Nb ₂ O ₅ /Y ₂ O ₃ is 0.1 ~2.5; 2) Y ₂ O ₃ /WO ₃ is 0.05~1.0; 3) Y ₂ O ₃ /TiO ₂ is 0.2~3.5; 4) 5×Nb ₂ O ₅ /(WO ₃ +Gd ₂ O ₃ ) is 0.05~1.5; 5) ZnO/La ₂ O ₃ is 0.2~0.8; 6) Gd ₂ O ₃ /(La ₂ O ₃ +Y ₂ O ₃ ) is 0.2~0.8; 7) (WO ₃ +ZnO)/( La ₂ O ₃ +TiO ₂ +ZrO ₂ ) is 0.5~1.0; 8) 5×Li ₂ O/(TiO ₂ +SiO ₂ ) is 0.05~5.0; 9) Nb ₂ O ₅ /WO ₃ is 0.03~0.7.

(7) According to the optical glass described in any one of (1)~(5), its components are expressed in weight percentage, wherein: B ₂ O ₃ : 10~18%; and/or La ₂ O ₃ : 25~38% %; and/or Gd ₂ O ₃ : 8~18%; and/or ZrO ₂ : 1~8%; and/or ZnO: 8~18%; and/or WO ₃ : 10~18%; and/or TiO ₂ : 0.5~7%; and/or SiO ₂ : 0.5~9%; and/or Y ₂ O ₃ : greater than 0 but less than or equal to 6%; and/or Yb ₂ O ₃ : 0~5%; and /or Nb ₂ O ₅ : 0.5~6%; and/or Rn ₂ O: 0~5%; and/or RO: 0~5%; and/or Al ₂ O ₃ : 0~2%; and/or Ta ₂ O ₅ : 0~2%; and/or clarifier: 0~0.5%, the Rn ₂ O is one or more of Li ₂ O, Na ₂ O, K ₂ O, RO is MgO, CaO, One or more of SrO and BaO, and the clarifying agent is one or more of Sb ₂ O ₃ , SnO ₂ , SnO, and CeO ₂ .

(8) According to the optical glass described in any one of (1)~(5), its components are expressed in weight percent, and satisfy at least one of the following nine situations: 1) Nb ₂ O ₅ /Y ₂ O ₃ is 0.25 ~1.5; 2) Y ₂ O ₃ /WO ₃ is 0.1~0.6; 3) Y ₂ O ₃ /TiO ₂ is 0.5~2.0; 4) 5×Nb ₂ O ₅ /(WO ₃ +Gd ₂ O ₃ ) is 0.1~1.0; 5) ZnO/La ₂ O ₃ is 0.3~0.7; 6) Gd ₂ O ₃ /(La ₂ O ₃ +Y ₂ O ₃ ) is 0.25~0.65; 7) (WO ₃ +ZnO)/( La ₂ O ₃ +TiO ₂ +ZrO ₂ ) is 0.6~0.9; 8) 5×Li ₂ O/(TiO ₂ +SiO ₂ ) is 0.1~2.0; 9) Nb ₂ O ₅ /WO ₃ is 0.05~0.5.

(9) According to the optical glass described in any one of (1)~(5), its components are represented by weight percentage, wherein: B ₂ O ₃ : 11~17%; and/or La ₂ O ₃ : 28~35% %; and/or Gd ₂ O ₃ : 9.5~16%, preferably Gd ₂ O ₃ : 11~16%; and/or ZrO ₂ : 2~6%; and/or ZnO: 10~16%, preferably ZnO: 11~16%; and/or WO ₃ : 12~17%; and/or TiO ₂ : 1~5%; and/or SiO ₂ : 1~8%, preferably SiO ₂ : 2~6%; and/or Y ₂ O ₃ : 1~5%; and/or Yb ₂ O ₃ : 0~2%; and/or Nb ₂ O ₅ : 1~5%; and/or Rn ₂ O: 0.5~3%; and/or or RO: 0~2%; and/or Al ₂ O ₃ : 0~1%; and/or Ta ₂ O ₅ : 0~1%; and/or clarifying agent: 0~0.1%, the Rn ₂ O One or more of Li ₂ O, Na ₂ O, K ₂ O, RO is one or more of MgO, CaO, SrO, BaO, clarifier is Sb ₂ O ₃ , SnO ₂ , SnO, CeO ₂ one or more.

(10) According to the optical glass described in any one of (1) to (5), its components are expressed in weight percent, and satisfy at least one of the following nine situations: 1) Nb ₂ O ₅ /Y ₂ O ₃ is 0.3 ~0.8; 2) Y ₂ O ₃ /WO ₃ is 0.1~0.4; 3) Y ₂ O ₃ /TiO ₂ is 0.8~1.3; 4) 5×Nb ₂ O ₅ /(WO ₃ +Gd ₂ O ₃ ) is 0.15~0.5; 5) ZnO/La ₂ O ₃ is 0.35~0.65; 6) Gd ₂ O ₃ /(La ₂ O ₃ +Y ₂ O ₃ ) is 0.35~0.55; 7) (WO ₃ +ZnO)/( La ₂ O ₃ +TiO ₂ +ZrO ₂ ) is 0.7~0.85; 8) 5×Li ₂ O/(TiO ₂ +SiO ₂ ) is 0.2~1.0; 9) Nb ₂ O ₅ /WO ₃ is 0.06~0.4.

(11) The optical glass according to any one of (1) to (5), the components of which are expressed in weight percent and satisfy one or more of the following five conditions: 1) Nb ₂ O ₅ /Y ₂ O ₃ is 0.4 ~0.7; 2) 5×Nb ₂ O ₅ /(WO ₃ +Gd ₂ O ₃ ) is 0.2~0.4; 3) ZnO/La ₂ O ₃ is 0.4~0.55; 4) 5×Li ₂ O/(TiO ₂ +SiO ₂ ) is 0.3~0.8; 5) Nb ₂ O ₅ /WO ₃ is 0.08~0.3.

(12) The optical glass according to any one of (1)~(5), its components are represented by weight percentage, wherein: Li ₂ O: 0~6%, preferably Li ₂ O: greater than 0 but less than or equal to 4% %, more preferably Li ₂ O: 0.1~3%, more preferably Li ₂ O: 0.5~2%; and/or Na ₂ O: 0~5%, preferably Na ₂ O: 0~3%, more preferably Na ₂ O: 0~2%; and/or K ₂ O: 0~5%, preferably K ₂ O: 0~3%, more preferably K ₂ O: 0~2%.

(13) According to the optical glass described in any one of (1) to (5), its components do not contain Ta ₂ O ₅ ; and/or do not contain GeO ₂ ; and/or do not contain F; and/or do not contain Al ₂ O ₃ ; and/or does not contain RO; and/or does not contain P ₂ O ₅ ; and/or does not contain Bi ₂ O ₃ .

(14) According to the optical glass described in any one of (1) to (5), the refractive index n _d of the optical glass is 1.85 to 1.91, preferably 1.86 to 1.90, more preferably 1.88 to 1.90; the Abbe number ν _d is 32-38.5, preferably 33-37.5, more preferably 34-37.

(15) According to the optical glass described in any one of (1) to (5), the acid resistance stability D _A of the optical glass is more than 3 types, preferably 2 or more types, more preferably 1 type; and/or The water resistance stability D _W is more than 2 types, preferably 1 type; and/or the density ρ is 5.50 g/cm ³ or less, preferably 5.40 g/cm ³ or less, more preferably 5.30 g/cm ³ or less, even more preferably Be less than or equal to 5.20g/cm ³ ; And/or λ ₇₀ is less than or equal to 410nm, preferably λ ₇₀ is less than or equal to 405nm, more preferably λ ₇₀ is less than or equal to 400nm, more preferably λ ₇₀ is less than or equal to 395nm; And/or λ ₅ is less than Or equal to _375nm , preferably λ5 is less than or equal to 370nm, more preferably _λ5 is less than or equal to 365nm, further preferably _λ5 is less than or equal to 360nm.

(16) The optical glass according to any one of (1) to (5), wherein the optical glass has a thermal expansion coefficient α _100/300°C of 100×10 ^-7 /K or less, preferably 95×10 ^-7 /K below, more preferably below 90×10 ^-7 /K; and/or transition temperature T _g below 620°C, preferably below 610°C, more preferably below 600°C; and/or crystallization upper limit temperature below 1250°C , preferably 1200°C or lower, more preferably 1180°C or lower, even more preferably 1160°C or lower.

(17) A glass prefabricated part made of the optical glass described in any one of (1) to (16).

(18) An optical element made of the optical glass described in any one of (1) to (16) or the glass preform described in (17).

(19) An optical instrument containing the optical glass described in any one of (1) to (16), and/or containing the optical element described in (18).

The beneficial effect of the invention is that: through reasonable component design, the optical glass obtained by the invention has lower transition temperature and thermal expansion coefficient, and is suitable for precision molding.

Below, the embodiment of the optical glass of the present invention will be described in detail, but the present invention It is not limited to the embodiment described below, and it can be implemented with appropriate changes within the scope of the purpose of the present invention. In addition, with regard to the repeated description, although the description may be appropriately omitted, the gist of the invention will not be limited accordingly. In the following content, the optical glass of the present invention is sometimes simply referred to as glass.

[Optical glass]

The scope of each component (ingredient) of the optical glass of the present invention will be described below. In the present invention, unless otherwise specified, the content and total content of each component are all expressed in weight percent (wt%), that is, the content of each component and the total content are relative to the total amount of glass substances converted into oxides. The amount is expressed in weight percent. Here, the "composition in terms of oxides" refers to the case where oxides, composite salts, hydroxides, etc. used as raw materials for the optical glass composition of the present invention are decomposed and converted into oxides during melting , and the total amount of the oxide is taken as 100%.

Unless otherwise indicated in specific circumstances, the numerical ranges listed in the present invention include upper and lower limit values, "above" and "below" include endpoint values, and include all integers and fractions within the range, without limitation Specific values listed when limiting ranges. The term "and/or" herein is inclusive, for example, "A and/or B" means only A, or only B, or both A and B.

<Essential Components and Optional Components>

B ₂ O ₃ is a network forming component in the present invention, which can improve the thermal stability of the glass and improve the meltability of the glass, so that the glass without the melting residue of the glass raw material can be obtained. In the present invention, by containing more than 8% For B ₂ O ₃ to obtain the above effects, the content of B ₂ O ₃ is preferably ₁₀ % or more, more preferably ₁₁ % or more. However, when the content _of B2O3 is too much, the refractive index of the glass will decrease and the chemical stability will deteriorate. Therefore, the upper limit _of the content of B2O3 in the present invention is ₂₀ %, preferably the upper limit is ₁₈ %, and more preferably the upper limit is 17%. .

SiO ₂ can improve the chemical stability of glass, maintain the viscosity suitable for molten glass forming, and reduce the erosion of refractory materials. If its content is too high, it will be more difficult to melt the glass, and it is not good for reducing the transition temperature of the glass. Therefore, in the present invention, the content of _SiO2 is 9% or less, preferably 0.5-9%, more preferably 1-8%, even more preferably 2-6%.

La ₂ O ₃ is a high-refraction and low-dispersion component, which can increase the refractive index of the glass and adjust the dispersion in the glass, and reduce the high-temperature viscosity of the glass. The content of La ₂ O ₃ in the present invention is more than 21%, preferably La ₂ O The content of ₃ is 25% or more, and the content of La ₂ O ₃ is more preferably 28% or more. On the other hand, by limiting the content of La ₂ O ₃ to less than 40%, the devitrification of the glass can be reduced by improving the stability of the glass, and the increase of the temperature coefficient of the refractive index and the Abbe number can be suppressed beyond the design requirements. Therefore, the content of La ₂ O ₃ is 40% or less, preferably 38% or less, more preferably 35% or less.

In the present invention, the chemical stability of the optical glass is improved by containing more than 6% of Gd ₂ O ₃ , and the thermal expansion coefficient and refractive index of the glass are adjusted. The content of Gd ₂ O ₃ is preferably more than 8%, more preferably Gd ₂ The O ₃ content is 9.5% or more, and the Gd ₂ O ₃ content is more preferably 11% or more. But when the Gd ₂ O ₃ content exceeds 20%, the devitrification resistance of the glass becomes poor, and the transition temperature of the glass increases. Therefore, the content of Gd ₂ O ₃ in the present invention is 20% or less, preferably 18% or less, more preferably 16% or less.

In the present invention, Y ₂ O ₃ is preferably contained below 10%. By combining Y ₂ O ₃ and La ₂ O ₃ at the same time, the melting property and devitrification resistance of the glass can be improved while maintaining high refractive index and low dispersion. If the content of Y ₂ O ₃ exceeds 10%, the stability and devitrification resistance of the glass will decrease, and the transition temperature will increase. Therefore, the content of Y ₂ O ₃ is 0-10%, preferably greater than 0 but less than or equal to 6%. In some embodiments, by containing more than 1% of Y ₂ O ₃ , the glass crystallization upper limit temperature and density can also be reduced. Therefore, the content of Y ₂ O ₃ in the present invention is more preferably 1-5%.

In some embodiments, if Gd ₂ O ₃ /(La ₂ O ₃ +Y ₂ O ₃ ) is lower than 0.2, the stability of the glass decreases, the temperature coefficient of the refractive index increases, and the glass is affected by temperature changes during use. Large; if Gd ₂ O ₃ /(La ₂ O ₃ +Y ₂ O ₃ ) exceeds 0.8, the abrasion degree of the glass will deteriorate and the density will increase. Therefore, preferably Gd ₂ O ₃ /(La ₂ O ₃ +Y ₂ O ₃ ) is 0.2 to 0.8, more preferably Gd ₂ O ₃ /(La ₂ O ₃ +Y ₂ O ₃ ) is 0.25 to 0.65, further preferably Gd ₂ O ₃ /(La ₂ O ₃ +Y ₂ O ₃ ) is 0.35~0.55.

Yb ₂ O ₃ is also a component that endows glass with high refraction and low dispersion performance. It is an optional component in the present invention. When its content exceeds 10%, the anti-devitrification performance and chemical stability of the glass will decrease, so Yb The content of ₂ O ₃ is limited to 0 to 10%, preferably 0 to 5%, more preferably 0 to 2%, and further preferably does not contain Yb ₂ O ₃ .

In the system glass of the present invention, ZnO can adjust the refractive index and dispersion of the glass, reduce the transition temperature, improve the anti-devitrification performance of the glass, and improve the stability of the glass. Melting at low temperature can improve the transmittance of glass. In the present invention, the above-mentioned effects are obtained by containing 7% or more of ZnO, preferably 8% or more of ZnO, more preferably 10% or more of ZnO, and even more preferably 11% or more of ZnO. On the other hand, if the content of ZnO is higher than 20%, the abrasion resistance of the glass becomes worse, the forming difficulty increases, and the devitrification resistance of the glass becomes worse. Therefore, the ZnO content is limited to 20% or less, preferably 18% or less, more preferably 16% or less.

In some embodiments of the present invention, by making the ratio ZnO/La ₂ O ₃ between the content of ZnO and the content of La ₂ O ₃ more than 0.2, the chemical stability and the temperature coefficient of refractive index of the glass can be improved, but if When ZnO/La ₂ O ₃ exceeds 0.8, the devitrification resistance of the glass decreases. Therefore, ZnO/La ₂ O ₃ is preferably 0.2 to 0.8, more preferably ZnO/La ₂ O ₃ is 0.3 to 0.7, further preferably ZnO/La ₂ O ₃ is 0.35 to 0.65, and even more preferably ZnO/La ₂ O ₃ is 0.4~0.55.

WO ₃ can increase the refractive index and mechanical strength of the glass, and reduce the transition temperature of the glass. In the present invention, the above-mentioned effect can be obtained by containing more than 8% WO ₃ . The lower limit of the content of WO ₃ is preferably 10%, and more preferably the lower limit of the content of WO ₃ 12%. If the WO ₃ content exceeds 20%, the thermal stability of the glass decreases, and the devitrification resistance decreases. Therefore, the upper limit of the content of WO ₃ is 20%, preferably 18%, more preferably 17%.

In some embodiments of the present invention, if Y ₂ O ₃ /WO ₃ is less than 0.05, the density of the glass will increase, which is not conducive to the realization of lightweight glass. If the Y ₂ O ₃ /WO ₃ exceeds 1.0, the thermal stability of the glass will decline. Therefore, Y ₂ O ₃ /WO ₃ is preferably 0.05 to 1.0, more preferably Y ₂ O ₃ /WO ₃ is 0.1 to 0.6, and even more preferably Y ₂ O ₃ /WO ₃ is 0.1 to 0.4.

Nb ₂ O ₅ is a high-refraction and high-dispersion component, which can increase the refractive index and devitrification resistance of the glass, and reduce the thermal expansion coefficient of the glass. If the content of Nb ₂ O ₅ is too high, the thermal and chemical stability of the glass will decrease , the light transmittance decreases. Therefore, the content of Nb ₂ O ₅ in the present invention is 0-8%, preferably 0.5-6%, more preferably 1-5%.

The inventors have found through a large number of experimental studies that in some embodiments of the present invention, Nb ₂ O ₅ , WO ₃ and Gd ₂ O ₃ will produce a complex synergistic effect in the glass, especially making 5×Nb ₂ O ₅ /( WO ₃ +Gd ₂ O ₃ ) in the range of 0.05~1.5, the glass can obtain good hot-press stability and also have a suitable degree of abrasion, preferably 5×Nb ₂ O ₅ /(WO ₃ +Gd ₂ O ₃ ) 0.1~1.0. Furthermore, by making 5×Nb ₂ O ₅ /(WO ₃ +Gd ₂ O ₃ ) in the range of 0.15~0.5, the thermal expansion coefficient of the glass can be further optimized, so 5×Nb ₂ O ₅ /(WO ₃ +Gd ₂ O ₃ ) is 0.15 to 0.5, more preferably 5×Nb ₂ O ₅ /(WO ₃ +Gd ₂ O ₃ ) is 0.2 to 0.4.

In some embodiments of the present invention, making Nb ₂ O ₅ /Y ₂ O ₃ more than 0.1 helps to improve the anti-devitrification performance of the glass, but if Nb ₂ O ₅ /Y ₂ O ₃ exceeds 2.5, the glass’s The coloring tendency increases and the light transmittance decreases. Therefore, preferably Nb ₂ O ₅ /Y ₂ O ₃ is 0.1 to 2.5, more preferably Nb ₂ O ₅ /Y ₂ O ₃ is 0.25 to 1.5, further preferably Nb ₂ O ₅ /Y ₂ O ₃ is 0.3 to 0.8, more preferably More preferably, Nb ₂ O ₅ /Y ₂ O ₃ is 0.4 to 0.7.

In some embodiments of the present invention, by making Nb ₂ O ₃ /WO ₃ in the range of 0.03~0.7, it helps to improve the thermal stability of the glass and optimize the chemical stability of the glass, preferably Nb ₂ O ₅ /WO ₃ 0.05 to 0.5, more preferably Nb ₂ O ₅ /WO ₃ is 0.06 to 0.4, further preferably Nb ₂ O ₅ /WO ₃ is 0.08 to 0.3.

TiO ₂ has the effect of increasing the refractive index and dispersion of the glass, and an appropriate amount can make the glass more stable and reduce the viscosity of the glass. However, if the TiO ₂ content exceeds 10%, the crystallization tendency of the glass increases, the transition temperature of the glass increases, and the glass becomes easily colored when press-molded. Therefore, the content of TiO ₂ in the present invention is greater than 0 but less than or equal to 10%, preferably the content of TiO ₂ is 0.5-7%, more preferably 1-5%.

In some embodiments of the present invention, the weather resistance of the glass can be improved by controlling the ratio Y ₂ O ₃ /TiO ₂ between the content of Y ₂ O ₃ and the content of TiO ₂ to be above 0.2, but if Y ₂ O ₃ When /TiO ₂ exceeds 3.5, the bubble degree of the glass deteriorates and the hardness decreases. Therefore, Y ₂ O ₃ /TiO ₂ is preferably 0.2-3.5, more preferably Y ₂ O ₃ /TiO ₂ is 0.5-2.0, and further preferably Y ₂ O ₃ /TiO ₂ is 0.8-1.3.

_ZrO2 is a high refraction and low dispersion component, which can increase the refractive index of the glass and adjust the dispersion in the glass, and improve the anti-devitrification performance of the glass. In the present invention, the above effects are obtained by containing more than ₁ % ZrO2, preferably ZrO The content of ₂ is 2% or more. If the content of ZrO ₂ is higher than 10%, it will be more difficult to melt the glass, and the melting temperature will rise, and furthermore, inclusions will appear inside the glass and the transmittance will decrease. Therefore, the ZrO2 content is ₁₀ % or less, preferably 8% or less, more preferably 6% or less.

In some embodiments of the present invention, by controlling the ratio of the total content of WO ₃ and ZnO between WO ₃ +ZnO and the total content of La ₂ O ₃ , TiO ₂ , and ZrO ₂ La ₂ O ₃ +TiO ₂ +ZrO ₂ (WO ₃ +ZnO)/(La ₂ O ₃ +TiO ₂ +ZrO ₂ ) is in the range of 0.3~1.5, the glass can obtain a lower coefficient of thermal expansion while having a lower transition temperature. Therefore, in the present invention, preferably (WO ₃ +ZnO)/(La ₂ O ₃ +TiO ₂ +ZrO ₂ ) is 0.3~1.5, more preferably (WO ₃ +ZnO)/(La ₂ O ₃ +TiO ₂ +ZrO ₂ ) is 0.5~1.0. Further, by controlling (WO ₃ +ZnO)/(La ₂ O ₃ +TiO ₂ +ZrO ₂ ) in the range of 0.6~0.9, the bubble degree and wear degree of the glass can be further optimized, so it is further preferred that (WO ₃ + ZnO)/(La ₂ O ₃ +TiO ₂ +ZrO ₂ ) is 0.6 to 0.9, more preferably (WO ₃ +ZnO)/(La ₂ O ₃ +TiO ₂ +ZrO ₂ ) is 0.7 to 0.85.

Rn ₂ O is an alkali metal oxide, and Rn ₂ O is one or more of Li ₂ O, Na ₂ O, and K ₂ O, which can improve the melting property of the glass and reduce the transition temperature of the glass. When the content of Rn ₂ O exceeds When the content is 10%, the resistance to devitrification of the glass becomes worse, and the refractive index drops significantly. Therefore, the content of Rn ₂ O in the present invention is 0-10%, preferably 0-5%, more preferably 0.5-3%.

Li ₂ O can reduce the transition temperature of glass, but when its content is high, it is unfavorable to the acid resistance stability and thermal expansion coefficient of glass. Therefore, the content of Li ₂ O in the present invention is 6% or less, preferably greater than 0 but less than or equal to 4% %, more preferably 0.1~3%, even more preferably 0.5~2%.

In some embodiments of the present invention, by making the value of 5×Li ₂ O/(TiO ₂ +SiO ₂ ) in the range of 0.05 to 5.0, the viscosity of the glass can be optimized, and the striation and air bubbles of the glass can be improved, preferably 5 ×Li ₂ O/(TiO ₂ +SiO ₂ ) is 0.1 to 2.0. Furthermore, if the value of 5×Li ₂ O/(TiO ₂ +SiO ₂ ) is in the range of 0.2-1.0, the moldability of the glass can be significantly improved and the probability of glass fogging during the molding process can be reduced. Therefore, it is more preferable that 5×Li ₂ O/(TiO ₂ +SiO ₂ ) is 0.2 to 1.0, and it is still more preferable that 5×Li ₂ O/(TiO ₂ +SiO ₂ ) is 0.3 to 0.8.

Na ₂ O has the effect of improving glass melting, can improve the glass melting effect, and can also reduce the glass transition temperature. If the Na ₂ O content exceeds 5%, the chemical stability and weather resistance of the glass will be reduced. Therefore, Na ₂ O The content of Na 2 O is 0~5%, preferably the content of Na ₂ O is 0~3%, more preferably the content of Na ₂ O is 0~2%.

K ₂ O has the effect of improving the thermal stability and melting property of glass, but its content exceeds 5%, the devitrification resistance of glass decreases, and the chemical stability of glass deteriorates, so the content of K ₂ O in the present invention is 5% or less, The content of K ₂ O is preferably 0-3%, more preferably 0-2%.

RO is an alkaline earth metal oxide, RO is one of MgO, CaO, SrO, BaO or more. Adding RO to the glass can improve the melting property of the glass and lower the transition temperature of the glass. If the RO content exceeds 10%, the devitrification resistance of the glass will decrease. Therefore, the RO content of the present invention is 0-10%, preferably 0-5%, more preferably 0-2%, and further preferably does not contain RO.

Al ₂ O ₃ can improve the chemical stability of the glass, but when its content exceeds 5%, the melting and transmittance of the glass will deteriorate. Therefore, the content of Al ₂ O ₃ in the present invention is 0-5%, preferably 0-2%, more preferably 0-1%, and further preferably does not contain Al ₂ O ₃ .

Ta ₂ O ₅ has the effect of increasing the refractive index and improving the devitrification resistance of the glass, but if its content is too high, the chemical stability of the glass will decrease, and it is difficult to control the optical constants to the desired range; on the other hand, compared with other components , Ta ₂ O ₅ is very expensive, and its usage should be reduced as far as possible from the viewpoint of practicality and cost. Therefore, the content of Ta ₂ O ₅ in the present invention is limited to 0-5%, preferably 0-2%, more preferably 0-1%, and further preferably does not contain Ta ₂ O ₅ .

In the present invention, by adding 0~1% of one or more of Sb ₂ O ₃ , SnO, SnO ₂ , and CeO ₂ components as a clarifier, the clarification effect of the glass can be improved, and the content of the clarifier is preferably 0~0.5% , more preferably 0~0.1%. When the Sb ₂ O ₃ content exceeds 1%, the glass has a tendency to reduce the clarification performance, and at the same time, due to its strong oxidation, it promotes the corrosion of the platinum or platinum alloy vessel of the molten glass and the deterioration of the forming mold, so the present invention preferably Sb ₂ The amount of O added is 0 to ₁ %, more preferably 0 to 0.5%, and even more preferably 0 to 0.1%. SnO and _SnO2 can also be added as clarifiers, but when the content exceeds 1%, the tendency of glass coloring increases, or when the glass is heated, softened, and reshaped by molding, etc., Sn will become the starting point of crystal nucleation , resulting in a tendency to devitrify. Therefore the content of _SnO of the present invention is preferably 0～1%, more preferably 0～0.5, more preferably 0～0.1%, more preferably does not contain; The content of SnO is preferably 0～1%, more preferably 0～0.5%. 0.5%, more preferably 0 to 0.1%, still more preferably not contained. The effect and the addition ratio of CeO ₂ are the same as those of SnO ₂ , and its content is preferably 0-1%, more preferably 0-0.5%, further preferably 0-0.1%, and still more preferably not contained.

An appropriate amount of F (fluorine) can be contained in the glass of the present invention, but in some embodiments, F will lead to poor glass stability and reduced devitrification resistance, and its volatility will lead to instability of glass optical constants and streaks degree becomes worse, so it is preferable not to contain F.

The glass of the present invention can contain an appropriate amount of GeO ₂ , but in some embodiments, the introduction of GeO ₂ will lead to a decrease in glass transmittance, and because it is an expensive raw material, it reduces the economical efficiency of the glass, so it is preferable not to use GeO 2 Contains GeO ₂ .

An appropriate amount of P ₂ O ₅ can be contained in the glass of the present invention, but in some embodiments, the inclusion of P ₂ O ₅ in the glass makes it difficult to obtain the desired high refractive index, and the devitrification resistance of the glass is reduced, so it is preferred Does not contain P ₂ O ₅ .

An appropriate amount of Bi ₂ O ₃ can be contained in the glass of the present invention, but in some embodiments, Bi ₂ O ₃ will cause the light transmittance of the glass to decrease, the degree of abrasion and chemical stability to deteriorate, and the density to increase significantly, so It is preferable not to contain Bi ₂ O ₃ .

<Components that should not be contained>

In the glass of the present invention, even if oxides of transition metals such as V, Cr, Mn, Fe, Co, Ni, Cu, Ag, and Mo are contained alone or in a small amount in combination, the glass will be colored, and in the visible light region Absorption at specific wavelengths weakens the visible light transmittance enhancement effect of the present invention. Therefore, it is preferable not to substantially contain it, especially in optical glasses that require transmittance at wavelengths in the visible light region.

Oxides of Th, Cd, Tl, Os, Re, and Se have tended to be controlled as harmful chemical substances in recent years, not only in the manufacturing process of glass, but also in the process of processing and disposal after production. Measures are required. Therefore, while paying attention to the impact on the environment, Except for unavoidable mixing, it is preferable not to contain them substantially. Thereby, the optical glass becomes practically free of environmental polluting substances. Therefore, the optical glass of the present invention can be manufactured, processed, and discarded without taking special environmental measures.

In order to be environmentally friendly, the optical glass of the present invention preferably does not contain As ₂ O ₃ and PbO. Although As ₂ O ₃ has the effect of eliminating bubbles and better preventing glass coloring, the addition of As ₂ O ₃ will increase the platinum erosion of the glass on the furnace, especially the platinum furnace, resulting in more platinum ions entering the glass. The service life of the platinum furnace is adversely affected.

"Does not contain" or "0%" described herein means that no such compound, molecule or element is intentionally added as a raw material to the optical glass of the present invention; but as a raw material and/or equipment for producing optical glass, there will be some Some impurities or components that are not intentionally added will be contained in small or trace amounts in the final optical glass, and this situation is also within the protection scope of the patent of the present invention.

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

<Refractive index and Abbe number>

The refractive index (n _d ) and Abbe number (ν _d ) of optical glass are tested according to the method specified in GB/T 7962.1-2010.

In some embodiments, the lower limit of the refractive index ( _nd ) of the optical glass of the present invention is 1.85, preferably 1.86, more preferably 1.88; the upper limit of the refractive index ( _nd ) is 1.91, preferably 1.90.

In some embodiments, the lower limit of the Abbe number (ν _d ) of the optical glass of the present invention is 32, preferably the lower limit is 33, more preferably the lower limit is 34; the upper limit of the Abbe number (ν _d ) is 38.5, preferably the upper limit is 37.5 , more preferably the upper limit is 37.

<density>

The density (ρ) of optical glass is tested according to the method specified in GB/T7962.20-2010.

In some embodiments, the density (ρ) of the optical glass of the present invention is 5.50 g/cm ³ or less, preferably 5.40 g/cm ³ or less, more preferably 5.30 g/cm ³ or less, even more preferably 5.20 g/cm ³ the following.

<Thermal expansion coefficient>

The thermal expansion coefficient of optical glass (α _100/300°C ) is tested according to the method specified in GB/T7962.16-2010, and the data of 100~300°C is tested.

In some embodiments, the thermal expansion coefficient (α _100/300°C ) of the optical glass of the present invention is 100×10 ^-7 /K or less, preferably 95×10 ^-7 /K or less, more preferably 90×10 ^-7 /K below.

<transition temperature>

The transition temperature (T _g ) of optical glass is tested according to the method specified in GB/T7962.16-2010.

In some embodiments, the transition temperature (T _g ) of the optical glass of the present invention is lower than 620°C, preferably lower than 610°C, more preferably lower than 600°C.

<coloring degree>

The short-wave transmission spectral properties of the glasses of the present invention are expressed by degrees of coloration (λ ₇₀ and λ ₅ ). λ ₇₀ refers to the corresponding wavelength when the glass transmittance reaches 70%. The measurement of λ ₇₀ is to measure the spectral transmittance in the wavelength range from 280nm to 700nm and show the wavelength at which the transmittance is 70% using glass with a thickness of 10±0.1mm having two opposite planes parallel to each other and optically polished. The so-called spectral transmittance or transmittance is the amount represented by I _out /I _in when the light of the intensity I _in is incident vertically on the above-mentioned surface of the glass, and the light of the intensity I _out is emitted from a plane through the glass, and also Contains the transmittance of the surface reflection loss on the above surface of the glass. The higher the refractive index of the glass, the greater the surface reflection loss. Therefore, in high refractive index glass, a small value of _λ70 means that the coloring of the glass itself is extremely small and the light transmittance is high.

In some embodiments, the λ ₇₀ of the optical glass of the present invention is less than or equal to 410nm, preferably λ ₇₀ is less than or equal to 405nm, more preferably λ ₇₀ is less than or equal to 400nm, further preferably λ ₇₀ is less than or equal to 395nm.

In some embodiments, the λ of the optical glass of the present invention is less than or equal to _375nm , preferably _λ is less than or equal to 370nm, more preferably _λ is less than or equal to 365nm, further preferably _λ is less than or equal to 360nm.

<Acid resistance stability>

The acid resistance stability (DA) (powder method) of optical glass is tested according to 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 3 or more, preferably 2 or more, and more preferably 1.

<Water Resistance Stability>

The water resistance stability (D _W ) (powder method) of optical glass is tested according to the method specified in GB/T 17129.

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.

<Crystalization upper limit temperature>

The crystallization performance of glass was measured by the temperature gradient furnace method. The glass was made into a sample of 180×10×10mm, the side was polished, and it was placed in a furnace with a temperature gradient (10°C/cm) and raised to 1300°C for 4 hours and then taken out. Naturally cool to room temperature, observe the crystallization of the glass under a microscope, the highest temperature corresponding to the appearance of crystals in the glass is the crystallization upper limit temperature of the glass.

In some embodiments, the crystallization upper limit temperature of the optical glass of the present invention is lower than 1250°C, preferably lower than 1200°C, more preferably lower than 1180°C, even more preferably lower than 1160°C.

[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 produced using conventional raw materials and processes, including but not limited to using carbonates, nitrates, sulfates, hydroxides, oxides, etc. as raw materials, and after batching according to conventional methods, Put the prepared charge into a smelting furnace (such as platinum crucible, alumina crucible, etc.) at 1200~1400°C for melting, and after clarification, stirring and homogenization, a homogeneous melting without bubbles and undissolved substances is obtained Glass is made by casting this molten glass in a mold and annealing it. Those skilled in the art can properly select raw materials, process methods and process parameters according to actual needs.

[Glass Preforms and Optical Components]

A glass preform can be produced from the produced optical glass by means of, for example, grinding processing, or compression molding such as reheat press molding, precision press molding, or the like. That is, the glass preform can be produced by mechanical processing such as grinding and grinding of optical glass, or by making a preform for compression molding from optical glass, and then grinding the preform after reheating and pressing. Glass preforms are produced by machining, or by precision stamping of preforms produced by grinding.

It should be noted that the means for preparing the glass preform are not limited to the above means. As described above, the optical glass of the present invention is useful for various optical elements and optical designs, wherein it is particularly preferable to form a preform from the optical glass of the present invention, and to use the preform for reheat press molding, precision press molding, etc., Make optical components such as lenses and prisms.

Both the glass preform and the optical element of the present invention are formed from the above-mentioned optical glass of the present invention. The glass preform of the present invention has the excellent characteristics that optical glass has; the optical element of the present invention With the excellent characteristics of optical glass, it can provide various optical components such as lenses and prisms with high optical value.

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

[Optical Instruments]

The optical elements formed from the optical glass of the present invention can be used to make optical instruments such as photographic equipment, imaging equipment, display devices, and monitoring equipment.

Example

<Example of Optical Glass>

In order to further clearly illustrate and illustrate the technical solution of the present invention, the following non-limiting examples are provided.

In this embodiment, optical glass having the compositions shown in Table 1 to Table 2 was obtained by adopting the above-mentioned manufacturing method of optical glass. In addition, the characteristics of each glass were measured by the test method described in the present invention, and the measurement results are shown in Tables 1 to 2.

<Example of glass preform>

The glass obtained in the optical glass examples 1 to 20 is used, for example, by means of grinding, Or hot pressing molding, precision stamping molding and other molding methods to make concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, plano-concave lenses and other lenses, prisms and other prefabricated parts.

<Example of optical element>

These preforms obtained in the above glass preform embodiment are annealed, and fine-tuning is performed while reducing the deformation inside the glass, so that the optical properties such as the refractive index reach the required values.

Next, each preform is ground and polished to produce various lenses and prisms such as concave meniscus lens, convex meniscus lens, biconvex lens, biconcave lens, plano-convex lens, and plano-concave lens. An antireflection film may be coated on the surface of the obtained optical element.

<Example of Optical Instrument>

The optical element prepared by the above optical element embodiment can be used for example in imaging equipment, sensor, microscope, medical technology, digital projection, communication, Optical communication technology/information transmission, optics/illumination in the automotive field, photolithography, excimer lasers, chips, computer chips, and integrated circuits and electronic devices including such circuits and chips, or used in the automotive field Camera equipment and installations.

Claims (31)

An optical glass, wherein its components are represented by weight percentage, including: B ₂ O ₃ : 8~20%; La ₂ O ₃ : 21~40%; Gd ₂ O ₃ : 6~20%; ZrO ₂ : 1 ~10%; ZnO: 7~20%; WO ₃ : 8~20%; TiO ₂ : greater than 0 but less than or equal to 10%; Y ₂ O ₃ : greater than 0 but less than or equal to 10%; where (WO ₃ + ZnO)/(La ₂ O ₃ +TiO ₂ +ZrO ₂ ) is 0.3~1.5, Gd ₂ O ₃ /(La ₂ O ₃ +Y ₂ O ₃ ) is 0.2~0.8, Y ₂ O ₃ /WO ₃ is 0.05 ~1.0. The optical glass according to Claim 1, wherein its components are expressed in weight percent, and further contain: SiO ₂ : 0~9%; and/or Yb ₂ O ₃ : 0~10%; and/or Nb ₂ O ₅ : 0~8%; and/or Rn ₂ O: 0~10%; and/or RO: 0~10%; and/or Al ₂ O ₃ : 0~5%; and/or Ta ₂ O ₅ : 0~5%; and/or clarifying agent: 0~1%, the Rn ₂ O is one or more of Li ₂ O, Na ₂ O, K ₂ O, RO is MgO, CaO, SrO, BaO One or more, the clarifying agent is one or more of Sb ₂ O ₃ , SnO ₂ , SnO, CeO ₂ . An optical glass, which contains B ₂ O ₃ , La ₂ O ₃ , Gd ₂ O ₃ , ZrO ₂ , ZnO, WO ₃ , TiO ₂ and Y ₂ O ₃ as essential components, and its components are expressed in weight percent, Where (WO ₃ +ZnO)/(La ₂ O ₃ +TiO ₂ +ZrO ₂ ) is 0.3~1.5, Gd ₂ O ₃ /(La ₂ O ₃ +Y ₂ O ₃ ) is 0.2~0.8, Y ₂ O ₃ /WO ₃ is 0.05-1.0, the optical glass has a refractive index n _d of 1.85-1.91, an Abbe number ν _d of 32-38.5, and a coefficient of thermal expansion α _100/300°C of 100×10 ^-7 /K or less. The optical glass as claimed in claim 3, wherein its components are expressed in weight percent, including: B ₂ O ₃ : 8-20%; and/or La ₂ O ₃ : 21-40%; and/or Gd ₂ O ₃ : 6~20%; and/or ZrO ₂ : 1~10%; and/or ZnO: 7~20%; and/or WO ₃ : 8~20%; and/or TiO ₂ : greater than 0 but less than or equal to 10%; and/or SiO ₂ : 0~9%; and/or Y ₂ O ₃ : greater than 0 but less than or equal to 10%; and/or Yb ₂ O ₃ : 0~10%; and/or Nb ₂ O ₅ : 0~8%; and/or Rn ₂ O: 0~10%; and/or RO: 0~10%; and/or Al ₂ O ₃ : 0~5%; and/or Ta ₂ O ₅ : 0~5%; and/or clarifying agent: 0~1%, the Rn ₂ O is one or more of Li ₂ O, Na ₂ O, K ₂ O, RO is MgO, CaO, SrO, BaO One or more of them, and the clarifying agent is one or more of Sb ₂ O ₃ , SnO ₂ , SnO, CeO ₂ . An optical glass, wherein its components are represented by weight percentage, consisting of B ₂ O ₃ : 8~20%; La ₂ O ₃ : 21~40%; Gd ₂ O ₃ : 6~20%; ZrO ₂ : 1~20% 10%; ZnO: 7~20%; WO ₃ : 8~20%; TiO ₂ : greater than 0 but less than or equal to 10%; SiO ₂ : 0~9%; Y ₂ O ₃ : greater than 0 but less than or equal to 10% %; Yb ₂ O ₃ : 0~10%; Nb ₂ O ₅ : 0~8%; Rn ₂ O : 0~10%; RO: 0~10%; Al ₂ O ₃ : 0~5%; Ta ₂ O ₅ : 0~5%; clarifying agent: 0~1% composition, where (WO ₃ +ZnO)/(La ₂ O ₃ +TiO ₂ +ZrO ₂ ) is 0.3~1.5, Gd ₂ O ₃ /(La ₂ O ₃ +Y ₂ O ₃ ) is 0.2~0.8, Y ₂ O ₃ /WO ₃ is 0.05~1.0, the Rn ₂ O is one or more of Li ₂ O, Na ₂ O, K ₂ O, RO is One or more of MgO, CaO, SrO, and BaO, and the clarifier is one or more of Sb ₂ O ₃ , SnO ₂ , SnO, and CeO ₂ . The optical glass as described in any one of claims 1 to 5, wherein its components are expressed in weight percent and satisfy at least one of the following seven situations: 1) Nb ₂ O ₅ /Y ₂ O ₃ is 0.1 ~2.5; 2) Y ₂ O ₃ /TiO ₂ is 0.2~3.5; 3) 5×Nb ₂ O ₅ /(WO ₃ +Gd ₂ O ₃ ) is 0.05~1.5; 4) ZnO/La ₂ O ₃ is 0.2 ~0.8; 5) (WO ₃ +ZnO)/(La ₂ O ₃ +TiO ₂ +ZrO ₂ ) is 0.5~1.0; 6) 5×Li ₂ O/(TiO ₂ +SiO ₂ ) is 0.05~5.0; 7 ) Nb ₂ O ₅ /WO ₃ is 0.03~0.7. The optical glass as described in any one of claims 1 to 5, wherein its components are expressed in weight percent, wherein: B ₂ O ₃ : 10-18%; and/or La ₂ O ₃ : 25-38% %; and/or Gd ₂ O ₃ : 8~18%; and/or ZrO ₂ : 1~8%; and/or ZnO: 8~18%; and/or WO ₃ : 10~18%; and/or TiO ₂ : 0.5~7%; and/or SiO ₂ : 0.5~9%; and/or Y ₂ O ₃ : greater than 0 but less than or equal to 6%; and/or Yb ₂ O ₃ : 0~5%; and /or Nb ₂ O ₅ : 0.5~6%; and/or Rn ₂ O: 0~5%; and/or RO: 0~5%; and/or Al ₂ O ₃ : 0~2%; and/or Ta ₂ O ₅ : 0~2%; and/or clarifier: 0~0.5%, the Rn ₂ O is one or more of Li ₂ O, Na ₂ O, K ₂ O, RO is MgO, CaO, One or more of SrO and BaO, and the clarifying agent is one or more of Sb ₂ O ₃ , SnO ₂ , SnO, and CeO ₂ . The optical glass as described in any one of claims 1 to 5, wherein its components are expressed in weight percentages and satisfy at least one of the following nine situations: 1) Nb ₂ O ₅ /Y ₂ O ₃ is 0.25 ~1.5; 2) Y ₂ O ₃ /WO ₃ is 0.1~0.6; 3) Y ₂ O ₃ /TiO ₂ is 0.5~2.0; 4) 5×Nb ₂ O ₅ /(WO ₃ +Gd ₂ O ₃ ) is 0.1~1.0; 5) ZnO/La ₂ O ₃ is 0.3~0.7; 6) Gd ₂ O ₃ /(La ₂ O ₃ +Y ₂ O ₃ ) is 0.25~0.65; 7) (WO ₃ +ZnO)/( La ₂ O ₃ +TiO ₂ +ZrO ₂ ) is 0.6~0.9; 8) 5×Li ₂ O/(TiO ₂ +SiO ₂ ) is 0.1~2.0; 9) Nb ₂ O ₅ /WO ₃ is 0.05~0.5. The optical glass as described in any one of claims 1 to 5, wherein its components are expressed in weight percent, wherein: B ₂ O ₃ : 11-17%; and/or La ₂ O ₃ : 28-35% %; and/or Gd ₂ O ₃ : 9.5~16%; and/or ZrO ₂ : 2~6%; and/or ZnO: 10~16%; and/or WO ₃ : 12~17%; and/or TiO ₂ : 1~5%; and/or SiO ₂ : 1~8%; and/or Y ₂ O ₃ : 1~5%; and/or Yb ₂ O ₃ : 0~2%; and/or Nb ₂ O ₅ : 1~5%; and/or Rn ₂ O: 0.5~3%; and/or RO: 0~2%; and/or Al ₂ O ₃ : 0~1%; and/or Ta ₂ O ₅ : 0~1%; and/or clarifying agent: 0~0.1%, the Rn ₂ O is one or more of Li ₂ O, Na ₂ O, K ₂ O, RO is MgO, CaO, SrO, BaO One or more of, clarifier is one or more of Sb ₂ O ₃ , SnO ₂ , SnO, CeO ₂ . The optical glass as described in any one of claims 1 to 5, wherein its components are expressed in weight percent, wherein: Gd ₂ O ₃ : 11-16%; and/or ZnO: 11-16%; and /or SiO ₂ : 2~6%. The optical glass as described in any one of claims 1 to 5, wherein its components are expressed in weight percent and satisfy at least one of the following nine conditions: 1) Nb ₂ O ₅ /Y ₂ O ₃ is 0.3 ~0.8; 2) Y ₂ O ₃ /WO ₃ is 0.1~0.4; 3) Y ₂ O ₃ /TiO ₂ is 0.8~1.3; 4) 5×Nb ₂ O ₅ /(WO ₃ +Gd ₂ O ₃ ) is 0.15~0.5; 5) ZnO/La ₂ O ₃ is 0.35~0.65; 6) Gd ₂ O ₃ /(La ₂ O ₃ +Y ₂ O ₃ ) is 0.35~0.55; 7) (WO ₃ +ZnO)/( La ₂ O ₃ +TiO ₂ +ZrO ₂ ) is 0.7~0.85; 8) 5×Li ₂ O/(TiO ₂ +SiO ₂ ) is 0.2~L.0; 9) Nb ₂ O ₅ /WO ₃ is 0.06~ 0.4. The optical glass as described in any one of claims 1 to 5, wherein its components are expressed in weight percent and satisfy one or more of the following five conditions: 1) Nb ₂ O ₅ /Y ₂ O ₃ is 0.4 ~0.7; 2) 5×Nb ₂ O ₅ /(WO ₃ +Gd ₂ O ₃ ) is 0.2~0.4; 3) ZnO/La ₂ O ₃ is 0.4~0.55; 4) 5×Li ₂ O/(TiO ₂ +SiO ₂ ) is 0.3~0.8; 5) Nb ₂ O ₅ /WO ₃ is 0.08~0.3. The optical glass as described in any one of claims 1 to 5, wherein its components are represented by weight percentage, wherein: Li ₂ O: 0~6%; and/or Na ₂ O: 0~5%; And/or K ₂ O: 0~5%. The optical glass according to any one of claims 1 to 5, wherein its components are expressed in weight percent, wherein: Li ₂ O: greater than 0 but less than or equal to 4%; and/or Na ₂ O: 0 ~3%; and/or K2O: ₀ ~3%. The optical glass as described in any one of claims 1 to 5, wherein its components are represented by weight percentage, wherein: Li ₂ O: 0.1~3%; and/or Na ₂ O: 0~2%; And/or K ₂ O: 0~2%. The optical glass as described in any one of claims 1 to 5, wherein its components are represented by weight percentage, wherein: Li ₂ O: 0.5~2%. The optical glass as described in any one of claims 1 to 5, wherein its components do not contain Ta ₂ O ₅ ; and/or do not contain GeO ₂ ; and/or do not contain F; and/or do not contain Al ₂ O ₃ ; and/or does not contain RO; and/or does not contain P ₂ O ₅ ; and/or does not contain Bi ₂ O ₃ . The optical glass according to any one of claims 1 to 5, wherein the optical glass has a refractive index nd of 1.85-1.91 _{; and an Abbe number ν d of} 32-38.5. The optical glass according to any one of claims 1 to 5, wherein the optical glass has a refractive index nd of 1.86-1.90 _{; and an Abbe number ν d of} 33-37.5. The optical glass according to any one of claims 1 to 5, wherein the optical glass has a refractive index _nd of 1.88-1.90; and an Abbe number ν _d of 34-37. The optical glass according to any one of claims 1 to 5, wherein the optical glass has an acid resistance stability D _A of 3 or more; and/or a water resistance stability D _W of 2 or more; and /or the density ρ is 5.50 g/cm ³ or less; and/or λ ₇₀ is less than or equal to 410 nm; and/or λ ₅ is less than or equal to 375 nm. The optical glass according to any one of claims 1 to 5, wherein the optical glass has an acid resistance stability D _A of class 2 or above; and/or a water resistance stability D _W of class 1; and/or Or the density ρ is 5.40g/cm ³ or less; and/or λ ₇₀ is less than or equal to 405nm; and/or λ ₅ is less than or equal to 370nm. The optical glass according to any one of claims 1 to 5, wherein, the acid resistance stability D _A of the optical glass is Class 1; and/or the density ρ is 5.30 g/cm ³ or less; and/or λ ₇₀ is less than or equal to 400 nm; and/or λ ₅ is less than or equal to 365 nm. The optical glass as described in any one of claims 1 to 5, wherein the density p of the optical glass is 5.20 g/cm ³ or less; and/or λ ₇₀ is less than or equal to 395 nm; and/or λ ₅ is less than Or equal to 360nm. The optical glass according to any one of claims 1 to 5, wherein the thermal expansion coefficient α _100/300°C of the optical glass is 100×10 ^-7 /K or less; and/or the transition temperature T _g is 620 below 1250°C; and/or the upper limit temperature of crystallization is below 1250°C. The optical glass according to any one of claims 1 to 5, wherein the thermal expansion coefficient α _100/300°C of the optical glass is 95×10 ^-7 /K or less; and/or the transition temperature T _g is 610 below 1200°C; and/or the upper limit temperature of crystallization is below 1200°C. The optical glass according to any one of claims 1 to 5, wherein the thermal expansion coefficient α _100/300°C of the optical glass is 90×10 ^-7 /K or less; and/or the transition temperature T _g is 600 below 1180°C; and/or the upper limit temperature of crystallization is below 1180°C. The optical glass according to any one of claims 1 to 5, wherein the crystallization upper limit temperature of the optical glass is below 1160°C. A glass preform, which is made of the optical glass described in any one of Claims 1 to 28. An optical element, wherein the optical glass described in any one of claims 1 to 28 or the glass preform described in claim 29 is used. An optical instrument, which contains the optical glass described in any one of Claims 1 to 28, and/or contains the optical element described in Claim 30.