TWI898656B - Optical glass, glass preforms, optical components and optical instruments - Google Patents

Abstract

The present invention provides an optical glass comprising, by weight, _3-18 % _SiO₂ + _B₂O₃ ; 45-65% _{La₂O₃ + Y₂O₃} + _Gd₂O₃ ; 3-13% _ZrO₂ ; 3-15% _Nb₂O₅ ; _and 8-22% _TiO₂ . _The ratio _{( La₂O₃} + _Gd₂O₃ )/ _Nb₂O₅ is _3.5-15.0 . Through a rational compositional design, the optical glass of the present invention possesses a desired refractive index and Abbe number, a low thermal expansion _coefficient , and excellent _light transmittance.

Description

Optical glass, glass preforms, optical components and optical instruments

The present invention relates to optical glass, and more particularly to optical glass having a refractive index of 1.98 or greater and an Abbe number of 22 to 31, as well as glass preforms, optical components, and optical instruments made thereof.

High-refractive-index optical glass is a key material for manufacturing diffractive waveguide components used in augmented reality/mixed reality (AR/MR) devices. Its refractive index determines the field of view (FOV) of AR/MR devices. For example, optical glass with a refractive index of 1.9 can achieve a 65° FOV. However, in practical applications, optical glass with a higher refractive index is required to enhance the FOV of AR/MR devices and provide users with a more realistic user experience. Furthermore, lenses formed from high-refractive-index optical glass can miniaturize optical systems. Market demand for ultra-high-refractive-index optical glass, with a refractive index of 1.98 or higher, is growing.

CN102050574A discloses an ultra-high refractive index optical glass with a refractive index of 2.0-2.3 and an Abbe _number of 17-25 _. This glass is a _B2O3 - _{Bi2O3 -Ga2O3 system} glass. Although it has a relatively high refractive index, its embodiments show that the optimal _λ70 is 490nm and the optimal _λ5 is 428nm. This glass has low light transmittance, which can significantly reduce the brightness of AR/MR devices. On the other hand, optical components installed in automotive optical instruments, as well as those installed in heat-generating optical instruments such as projectors, copiers, and laser printers, are used in environments with large temperature fluctuations. If the thermal expansion coefficient of the optical glass is too large, the thermal expansion of the optical component due to changes in ambient temperature will differ from the expansion coefficient of the fixture holding the optical component, generating stress in the optical component and causing birefringence, which in turn causes changes in imaging characteristics. Therefore, optical glass with a low thermal expansion coefficient is desirable.

The technical problem to be solved by the present invention is to provide an optical glass with a refractive index of 1.98 or greater, an Abbe number of 22 to 31, a low thermal expansion coefficient, and excellent light transmittance.

The technical solution adopted by the present invention to solve the technical problem is:

(1) Optical glass, the components of which, expressed in percentage by weight, contain: _SiO₂ + _B₂O₃ : 3-18%; _{La₂O₃ + Y₂O₃ + Gd₂O₃} : _45-65 %; _ZrO₂ : _3-13 %; _Nb₂O₅ : 3-15%; _TiO₂ : 8-22%, wherein _{the ratio ( La₂O₃} + _{Gd₂O₃ )} / _Nb₂O₅ is 3.5-15.0.

(2) The optical glass according to (1), wherein the components are expressed in weight percentage and further contain: ZnO: 0-5%; and/or RO: 0-6%; and/or _Rn2O : 0-5%; and _/ or _WO3 : 0-5%; and/or _Ta2O5 : 0-5%; and/or _Al2O3 : 0-5%; and/or _Yb2O3 : 0-8%; and/or _GeO2 : 0-3%; and/or _P2O5 : 0-4%; and/or _clarifier : 0-1%, wherein RO _is one or _more of MgO, CaO, SrO, and BaO, _Rn2O is one or more of _Li2O , _Na2O , and _K2O , and the clarifier is one or more of _Sb2O3 , _SnO2 , and _{CeO2 .}

(3) Optical glass containing _ZrO2 , _Nb2O5 , _{and TiO2} as essential components, wherein the composition, expressed in weight percentage, comprises 3-18% of _SiO2 + _B2O3 and 45-65% _{of La2O3} + _Y2O3 + _Gd2O3 , wherein _{( La2O3} + _Gd2O3 )/ _Nb2O5 is _3.5-15.0 , and the optical glass has a refractive index _nd of not less than 1.98, _an Abbe number _νd of 22-31, _and a thermal expansion coefficient α _{at -30/ 70 ° C} of not more than 90× ^10-7 /K.

(4) The optical glass according to (3), wherein the composition is expressed in weight percentage and further comprises: ZrO ₂ : 3-13%; and/or Nb ₂ O ₅ : 3-15%; and/or TiO ₂ : 8-22%; and/or ZnO: 0-5%; and/or RO: 0-6%; and/or Rn ₂ O: 0-5%; and/or WO ₃ : 0-5%; and/or Ta ₂ O ₅ : 0-5%; and/or Al ₂ O ₃ : 0-5%; and/or Yb ₂ O ₃ : 0-8%; and/or GeO 2 : 0-3%; and/or P ₂ O ₅ : 0-4%; and/or clarifier: 0-1%, wherein the RO is one or more of MgO, CaO, SrO, and BaO, and the Rn ₂ O is Li ₂ O _, Na ₂ O, K _{2 O} , or the like. The clarifier is one or more of Sb ₂ O ₃ , SnO ₂ , and CeO ₂ .

(5) The optical glass according to any one of (1) to (4), wherein the composition is expressed in weight percentage, wherein: (La ₂ O ₃ +Gd ₂ O ₃ )/Nb ₂ O ₅ is 4.0 to 10.0, preferably (La ₂ O ₃ +Gd ₂ O ₃ )/Nb ₂ O ₅ is 5.0 to 8.0, and more preferably (La ₂ O ₃ +Gd ₂ O ₃ )/Nb ₂ O ₅ is 5.5 to 6.5.

(6) The optical glass according to any one of (1) to (4), wherein the composition is expressed in weight percentage, wherein: _SiO2 / _B2O3 is _0.4 to 4.0, preferably _SiO2 / _B2O3 is 0.5 to _3.0 , more preferably _SiO2 / _B2O3 is _0.6 to 2.0, and further preferably _SiO2 / _B2O3 is 0.7 to 1.2 _.

(7) The optical glass according to any one of (1) to (4), wherein the composition is expressed in weight percentage, wherein: (ZnO + Y ₂ O ₃ ) / Gd ₂ O ₃ is less than 0.8, preferably (ZnO + Y ₂ O ₃ ) / Gd ₂ O ₃ is less than 0.6, more preferably (ZnO + Y ₂ O ₃ ) / Gd ₂ O ₃ is 0.01 to 0.5, and further preferably (ZnO + Y ₂ O ₃ ) / Gd ₂ O ₃ is 0.05 to 0.3.

(8) The optical glass according to any one of (1) to (4), wherein the composition is expressed in weight percentage, wherein: (SiO ₂ + B ₂ O ₃ )/Gd ₂ O ₃ is 0.3 to 2.5, preferably (SiO ₂ + B ₂ O ₃ )/Gd ₂ O ₃ is 0.4 to 2.0, more preferably (SiO ₂ + B ₂ O ₃ )/Gd ₂ O ₃ is 0.5 to 1.5, and further preferably (SiO ₂ + B ₂ O ₃ )/Gd ₂ O ₃ is 0.7 to 1.2.

(9) The optical glass according to any one of (1) to (4), wherein the composition is expressed in weight percentage, wherein: ZnO/(SiO ₂ + B ₂ O ₃ ) is less than 0.8, preferably ZnO/(SiO ₂ + B ₂ O ₃ ) is less than 0.6, more preferably ZnO/(SiO ₂ + B ₂ O ₃ ) is 0.01 to 0.5, and further preferably ZnO/(SiO ₂ + B ₂ O ₃ ) is 0.02 to 0.3.

(10) The optical glass according to any one of (1) to (4), wherein the composition is expressed in weight percentage, wherein: (SiO ₂ + B ₂ O ₃ + La ₂ O ₃ )/ZrO ₂ is 4.0 to 15.0, preferably (SiO ₂ + B ₂ O ₃ + La ₂ O ₃ )/ZrO ₂ is 5.0 to 12.0, more preferably (SiO ₂ + B ₂ O ₃ + La ₂ O ₃ )/ZrO ₂ is 6.5 to 10.0, and further preferably (SiO ₂ + B ₂ O ₃ + La ₂ O ₃ )/ZrO ₂ is 7.5 to 9.0.

(11) The optical glass _according to any one of (1) to (4), wherein the composition is expressed in weight percentage, wherein: _B2O3 / _TiO2 is 0.1 to 1.0, preferably _B2O3 / _TiO2 is _0.2 to 0.8, more preferably _B2O3 / _TiO2 is _0.2 to 0.7, and further preferably _B2O3 / _TiO2 is _0.3 to 0.5.

(12) The optical glass according to any one of (1) to (4), wherein the composition is expressed in weight percentage, wherein: (Gd ₂ O ₃ +Nb ₂ O ₅ +TiO ₂ )/(SiO ₂ +B ₂ O ₃ ) is 1.0 to 8.0, preferably (Gd ₂ O ₃ +Nb ₂ O ₅ +TiO ₂ )/(SiO ₂ +B ₂ O ₃ ) is 1.5 to 6.0, more preferably (Gd ₂ O ₃ +Nb ₂ O ₅ +TiO ₂ )/(SiO ₂ +B ₂ O ₃ ) is 2.0 to 5.0, and further preferably (Gd ₂ O ₃ +Nb ₂ O ₅ +TiO ₂ )/(SiO ₂ +B ₂ O ₃ ) is 2.5 to 4.0.

(13) The optical glass according to any one of (1) to (4), wherein the composition is expressed in weight percentage, wherein: (Gd ₂ O ₃ +TiO ₂ )/(La ₂ O ₃ +Nb ₂ O ₅ ) is 0.3 to 0.9, preferably (Gd ₂ O ₃ +TiO ₂ )/(La ₂ O ₃ +Nb ₂ O ₅ ) is 0.35 to 0.8, more preferably (Gd ₂ O ₃ +TiO ₂ )/(La ₂ O ₃ +Nb ₂ O ₅ ) is 0.4 to 0.7, and further preferably (Gd ₂ O ₃ +TiO ₂ )/(La ₂ O ₃ +Nb ₂ O ₅ ) is 0.45 to 0.6.

(14) The optical glass according to any one of (1) to (4), wherein the composition is expressed in weight percentage, wherein: (B ₂ O ₃ +La ₂ O ₃ )/(Gd ₂ O ₃ +Nb ₂ O ₅ +TiO ₂ ) is 0.7 to 2.5, preferably (B ₂ O ₃ +La ₂ O ₃ )/(Gd ₂ O ₃ +Nb ₂ O ₅ +TiO ₂ ) is 0.8 to 2.0, more preferably (B ₂ O ₃ +La ₂ O ₃ )/(Gd ₂ O ₃ +Nb ₂ O ₅ +TiO ₂ ) is 0.9 to 1.7, and further preferably (B ₂ O ₃ +La ₂ O ₃ )/(Gd ₂ O ₃ +Nb ₂ O ₅ +TiO ₂ ) is 1.0 to 1.5.

(15) The optical glass according to any one of (1) to (4), wherein the composition is expressed in weight percentage, wherein: (B ₂ O ₃ +La ₂ O ₃ )/(Gd ₂ O ₃ +SiO ₂ ) is 1.5 to 5.5, preferably (B ₂ O ₃ +La ₂ O ₃ )/(Gd ₂ O ₃ +SiO ₂ ) is 2.0 to 4.0, more preferably (B ₂ O ₃ +La ₂ O ₃ )/(Gd ₂ O ₃ +SiO ₂ ) is 2.3 to 3.3, and further preferably (B ₂ O ₃ +La ₂ O ₃ )/(Gd ₂ O ₃ +SiO ₂ ) is 2.5 to 3.2.

(16) The optical glass according to any one of (1) to (4), wherein the composition is expressed in weight percentage, wherein: B ₂ O ₃ /(ZrO ₂ +Y ₂ O ₃ ) is 0.2 to 2.5, preferably B ₂ O ₃ /(ZrO ₂ +Y ₂ O ₃ ) is 0.4 to 2.0, more preferably B ₂ O ₃ /(ZrO ₂ +Y ₂ O ₃ ) is 0.5 to 1.5, and further preferably B ₂ O ₃ /(ZrO ₂ +Y ₂ O ₃ ) is 0.6 to 1.0.

(17) The optical glass according to any one of (1) to (4), wherein the composition is expressed in weight percentage, wherein: RO/ _Nb2O5 is less than _0.8 , preferably RO/ _Nb2O5 is less than _0.5 , more preferably RO/ _Nb2O5 is less than _0.3 , and further preferably RO/ _Nb2O5 is _less than 0.1, and the RO is one or more of MgO, CaO, SrO, and BaO.

(18) The optical glass according to any one of (1) to (4), wherein the composition is expressed in weight percentage, wherein: (B ₂ O ₃ +La ₂ O ₃ +Y ₂ O ₃ +RO)/Gd ₂ O ₃ is 2.0 to 7.0, preferably (B ₂ O ₃ +La ₂ O ₃ +Y ₂ O ₃ +RO)/Gd ₂ O ₃ is 2.5 to 6.0, more preferably (B ₂ O ₃ +La ₂ O ₃ +Y ₂ O ₃ +RO)/Gd ₂ O ₃ is 3.0 to 4.6, and further preferably (B ₂ O ₃ +La ₂ O ₃ +Y ₂ O ₃ +RO)/Gd ₂ O ₃ is 3.5 to 4.5, and the RO is one or more of MgO, CaO, SrO, and BaO.

(19) The optical glass according to any one of (1) to (4), wherein the composition is expressed in weight percentage, wherein: (RO + GeO ₂ + Y ₂ O ₃ + Ta ₂ O ₅ ) / La ₂ O ₃ is less than 0.3, preferably (RO + GeO ₂ + Y ₂ O ₃ + Ta ₂ O ₅ ) / La ₂ O ₃ is less than 0.2, more preferably (RO + GeO ₂ + Y ₂ O ₃ + Ta ₂ O ₅ ) / La ₂ O ₃ is less than 0.15, and further preferably (RO + GeO ₂ + Y ₂ O ₃ + Ta ₂ O ₅ ) / La ₂ O ₃ is less than 0.1, and the RO is one or more of MgO, CaO, SrO, and BaO.

(20) The optical glass according to any one of (1) to (4), wherein the components thereof are expressed in weight percentages, wherein: SiO ₂ +B ₂ O ₃ : 5-15%, preferably SiO ₂ +B ₂ O ₃ : 7-13%; and/or La ₂ O ₃ +Y ₂ O ₃ +Gd ₂ O ₃ : 50-63%, preferably La ₂ O ₃ +Y ₂ O ₃ +Gd ₂ O ₃ : 52-60%; and/or ZrO ₂ : 4-11%, preferably ZrO ₂ : 6-10%; and/or Nb ₂ O ₅ : 5-13%, preferably Nb ₂ O ₅ : 7-12%; and/or TiO ₂ : 10-20%, preferably TiO ₂ : 13-18%; and/or ZnO: 0-4%, preferably ZnO: 0.1-3%; and/or RO: 0-4%, preferably RO: 0-2%; and/or Rn ₂ O: 0-3%, preferably Rn ₂ O: 0-1%; and/or WO ₃ : 0-3%, preferably WO ₃ : 0-1%; and/or Ta ₂ O ₅ : 0-3%, preferably Ta ₂ O ₅ : 0-1%; and/or Al ₂ O ₃ : 0-3%, preferably Al ₂ O ₃ : 0-1%; and/or Yb ₂ O ₃ : 0-5%, preferably Yb ₂ O ₃ : 0-1%; and/or GeO ₂ : 0-2%, preferably GeO ₂ : 0-1%; and/or P ₂ O ₅ : 0-2%, preferably P ₂ O ₅ : 0-1%; and/or clarifier: 0-0.5%, preferably clarifier: 0-0.2%, RO is one or more of MgO, CaO, SrO, and BaO, _Rn2O is one or more of _Li2O , _Na2O , and _K2O , and the clarifier is one or more _{of Sb2O3} , _SnO2 , and _CeO2 .

(21) The optical glass according to any one of (1) to (4), wherein the components thereof are expressed in weight percentages, wherein: SiO ₂ : 1-10%, preferably SiO ₂ : 2-8%, more preferably SiO ₂ : 3-7%; and/or B ₂ O ₃ : 1-10%, preferably B ₂ O ₃ : 2-9%, more preferably B ₂ O ₃ : 4-8%; and/or La ₂ O ₃ : 35-50%, preferably La ₂ O ₃ : 37-47%, more preferably La ₂ O ₃ : 41-46%; and/or Y ₂ O ₃ : 0-6%, preferably Y ₂ O ₃ : 0-4%, more preferably Y ₂ O ₃ : 0.1-3%; and/or Gd ₂ O ₃ : 6-20%, preferably Gd ₂ O ₃ : 8-18%, more preferably Gd ₂ O ₃ ：11～15%.

(22) The optical glass according to any one of (1) to (4), wherein the composition does not contain WO ₃ ; and/or does not contain Ta ₂ O ₅ ; and/or does not contain RO; and/or does not contain Rn ₂ O; and/or does not contain P ₂ O ₅ ; and/or does not contain Al ₂ O ₃ ; and/or does not contain GeO ₂ ; and/or does not contain Yb ₂ O ₃ , wherein RO is one or more of MgO, CaO, SrO, and BaO, and Rn ₂ O is one or more of Li ₂ O, Na ₂ O, and K ₂ O.

(23) The optical glass according to any one of (1) to (4) has a refractive index n _d of 1.98 or greater, preferably 1.99 or greater, more preferably 2.00 to 2.15, further preferably 2.01 to 2.10, further preferably 2.03 to 2.07, and an Abbe number v _d of 22 to 31, preferably 23 to 30, more preferably 24 to 29, further preferably 25 to 28.

(24) The optical glass according to any one of (1) to (4) has a thermal expansion coefficient α _{-30/70 °C} of 90 × 10 ^-7 /K or less, preferably 80 × 10 ^-7 /K or less, more preferably 75 × 10 ^-7 /K or less; and/or an acid resistance stability _DA of Class 2 or higher, preferably Class 1; and/or a λ ₇₀ of 480 nm or lower, preferably 470 _nm or lower, more preferably 465 _nm or lower; and/or a λ ₅ of 390 nm or lower, preferably 380 _nm or lower, more preferably 375 _nm or lower; and/or a weather resistance CR of Class 2 or higher, preferably Class 1; and/or a Knoop hardness H _K of 630 × 10 ⁷ Pa or higher, preferably 650 × 10 ⁷ Pa or higher, more preferably 660 × 10 ⁷ Pa or above; and/or Young's modulus E is 11000×10 ⁷ Pa or above, preferably 12000×10 ⁷ Pa or above, more preferably 13000×10 ⁷ Pa or above; and/or the bubble degree is A grade or above, preferably _A0 grade or above, more preferably _A00 grade; and/or the density ρ is 5.50 g/cm ³ or below, preferably 5.40 g/cm ³ or below, more preferably 5.30 g/cm ³ or below; and/or the abrasion resistance _FA is 90-140, preferably 100-130, more preferably 110-123.

(25) A glass preform made of any optical glass described in (1) to (24).

(26) An optical element made of any of the optical glasses described in (1) to (24), or made of the glass preform described in (25).

(27) An optical instrument comprising the optical glass described in any one of (1) to (24) and/or the optical element described in (26).

The beneficial effect of the present invention is that, through reasonable component design, the optical glass of the present invention has a desired refractive index and Abbe number, as well as a low thermal expansion coefficient and excellent light transmittance.

The following describes in detail embodiments of the optical glass of the present invention. However, the present invention is not limited to the embodiments described below and can be implemented with appropriate modifications within the scope of the present invention. Furthermore, although some overlapping descriptions may be omitted, this does not limit the scope of the invention. In the following description, the optical glass of the present invention will sometimes be referred to simply as "glass." [Optical Glass]

The following describes the ranges of the various components (ingredients) of the optical glass of the present invention. Unless otherwise specified, the content and total content of each component are expressed in weight percentage (wt%), that is, the content and total content of each component are expressed as the weight percentage relative to the total amount of the glass material converted into oxide composition. Here, "composition converted into oxide composition" means that, when the oxides, complex salts, and hydroxides used as raw materials for the optical glass of the present invention decompose and convert into oxides during melting, the total amount of the oxide material is taken as 100%.

Unless otherwise specified under specific circumstances, the numerical ranges listed in this invention include upper and lower limits, and "above" and "below" include the endpoints and all integers and fractions within the range, without being limited to the specific values listed when defining the range. The term "and/or" herein is inclusive; for example, "A and/or B" means only A, only B, or both A and B. <Required and Optional Components>

_SiO₂ increases the viscosity of molten glass, reduces glass coloration, improves the chemical stability of glass, and enhances its resistance to devitrification. In the present invention, these effects are achieved by containing at least 1% _SiO₂ . The _SiO₂ content is preferably at least 2%, and more preferably at least 3%. _{Excessive SiO₂} content increases the difficulty of melting the glass, raises the transition temperature, and reduces the refractive index. Therefore, in the present invention, the upper limit of the _SiO₂ content is 10%, preferably 8%, and more preferably 7%.

_B₂O₃ improves the meltability and devitrification resistance of glass, helping to lower its transition temperature. The present invention achieves this effect by containing at least 1% _{B₂O₃ ,} preferably at least _{2 %} , and more preferably at least 4 _% . Excessive _B₂O₃ content deteriorates the chemical stability of the glass and reduces _{its refractive} index, hindering the high refractive index achieved in the _present invention. Therefore, _{the B₂O₃} content is 10% or less, preferably 9% or less, and more preferably 8% or less.

In some embodiments, controlling the combined content of _SiO2 and _{B2O3 ( SiO2} + _{B2O3 )} within the range of 3-18% helps improve the chemical stability of the glass and optimizes its abrasiveness. _Therefore , the _SiO2 + _{B2O3 ratio} is preferably _3-18 %, more preferably _5-15 %, and even more _{preferably 7-13 %} .

In some embodiments, controlling the ratio of _SiO2 to _B2O3 ( _SiO2 / _{B2O3 )} within the range of _0.4 to 4.0 can improve the anti-devitrification properties of the glass and optimize its weather resistance and Young's modulus. Therefore, the _SiO2 / _{B2O3 ratio} is preferably 0.4 to 4.0, more preferably _0.5 to _3.0 , further preferably _{0.6 to 2.0 , and} even _more preferably 0.7 to _1.2 .

_La₂O₃ is _an effective component for increasing the refractive index of glass, significantly improving its chemical stability and resistance to devitrification. If its content is less than 35%, achieving the required optical constants is difficult. If it exceeds 50%, the glass's devitrification tendency increases, and _its thermal stability deteriorates. Therefore, the _La₂O₃ content is limited to 35-50%, preferably 37-47%, and even more preferably 41-46%.

_Gd2O3 can increase the refractive index and chemical stability of glass, improving its thermal stability. However, if its content is too high, the glass's resistance to devitrification _will deteriorate and the raw material cost _will increase. Therefore, the _Gd2O3 content is 6-20%, preferably 8-18%, and more preferably 11-15%.

In some embodiments, _{the ratio of the combined content of SiO2 and B2O3 (SiO2 + B2O3) to the content of Gd2O3 ( ( SiO2} + _B2O3 )/ _Gd2O3 ) ₎ is controlled within the range of 0.3 to 2.5 to optimize the abrasiveness and blistering _of the glass and increase the Young's modulus of the glass. Therefore, _{( SiO2} + _{B2O3 )} / _Gd2O3 is preferably _0.3 to _2.5 , more preferably _{0.4 to 2.0 ,} further _{preferably 0.5} to _1.5 , _and even more _{preferably 0.7 to 1.2 .}

In some embodiments, controlling the ratio of the combined content of _B2O3 and _La2O3 ( _B2O3 + _{La2O3 ) to the combined content of Gd2O3 and SiO2 (Gd2O3 +SiO2) ((B2O3 +La2O3 ) / ( Gd2O3 + SiO2 ) ) within the range of 1.5} to 5.5 helps reduce the density of the glass and improve the chemical stability of the glass. Therefore, the ratio of ( _{B2O3 + La2O3} ) _/ ( _Gd2O3 + _SiO2 ) is preferably 1.5 to 5.5, _{and more preferably (B2O3 +La2O3)/(Gd2O3 + SiO2 ) is 2.0 to 4.0} . Furthermore, controlling the ( _B2O3 + _La2O3 )/ _{( Gd2O3} + _SiO2 ) ratio within the range of _2.3 to 3.3 can further optimize the glass's bubble density and Young's modulus. Therefore, _a ( _B2O3 + _La2O3 )/ _{( Gd2O3} + _SiO2 ) ratio of 2.3 to 3.3 is more preferred, and _{a ( B2O3} + _La2O3 )/ _{( Gd2O3} + _{SiO2 ) ratio} of 2.5 to 3.2 is even more preferred.

_Y2O3 can improve the refractive index and devitrification resistance of glass. However, if _its content is too high, the chemical stability and weather resistance of the _glass will deteriorate. Therefore, the content of _Y2O3 in the present invention is 0-6%, preferably 0-4%, and more preferably 0.1-3%.

In some embodiments, the combined content _{of La2O3, Y2O3 , and Gd2O3 ( La2O3 + Y2O3} + _{Gd2O3 )} is controlled within the range of 45-65%. _{This makes} it easier for the glass to achieve a desired refractive index and Abbe _number , _and optimizes _{the glass} 's devitrification resistance and weather resistance. Therefore, _{the La2O3} + _{Y2O3 + Gd2O3 content} is preferably _45-65 %, more _preferably 50-63 _% , and even _{more preferably 52-60 % .}

_Yb2O3 is _a component that imparts high refractive index and low dispersion to glass. If its content exceeds 8%, the glass's anti-devitrification properties decrease. Therefore, the _Yb2O3 content is 0-8%, preferably 0-5%, and more preferably 0-1%. It is even more preferred that _{the glass} contain no _Yb2O3 .

_ZrO₂ can enhance the glass's resistance to devitrification, improving its chemical stability and mechanical properties. However, excessive ZrO₂ content increases melting difficulty, increases melting temperatures, and can lead to inclusions within the glass and a decrease in light transmittance. Therefore, the _ZrO₂ content in the present invention is 3-13%, preferably 4-11%, and even more preferably 6-10%.

In some embodiments, controlling the ratio of the combined content _{of SiO2} , _B2O3 , and _{La2O3 ( SiO2} + _B2O3 + _{La2O3 )} to the content _{of ZrO2} (( _SiO2 + _B2O3 + _{La2O3 )} / _{ZrO2 )} within the range of 4.0 to 15.0 can increase the Young's modulus and hardness of the glass and optimize the weather resistance of the glass. Therefore, ( _SiO2 + _B2O3 + _La2O3 )/ _ZrO2 is preferably 4.0 to _15.0 , more preferably ( _SiO2 + _B2O3 + _La2O3 )/ZrO2 _is 5.0 to 12.0, further preferably ( _SiO2 + _{B2O3 + La2O3} )/ _ZrO2 is 6.5 to _10.0 , and even _{more preferably ( SiO2} + _B2O3 + _La2O3 )/ _ZrO2 is _7.5 to _9.0 .

In some embodiments, controlling the _ratio of _B2O3 to the total content _{of ZrO2} and _Y2O3 ( _ZrO2 + _{Y2O3 )} ( _B2O3 /( _ZrO2 + _{Y2O3 )} ) within the range of 0.2 to _2.5 can improve the chemical stability and thermal expansion coefficient of the glass and prevent the hardness of the glass from decreasing. _{Therefore , B2O3 / ( ZrO2 + Y2O3 )} is _preferably 0.2-2.5 _, more _{preferably 0.4-2.0} , further preferably _0.5-1.5 , _{and even more preferably 0.6-1.0 .}

_Nb2O5 can increase the refractive index and devitrification resistance of glass and reduce its thermal expansion coefficient. In the present invention _, these effects are achieved by containing at least 3% _{Nb2O5 .} The preferred lower limit for the _Nb2O5 content is 5%, and _more preferably 7%. If the _Nb2O5 content exceeds 15%, the thermal stability and weather resistance of the glass _will decrease, and the light transmittance will fall. Therefore, in the present invention, the upper limit of _{the Nb2O5} content is 15%, with a preferred upper limit of 13% and a more preferred upper limit of 12%.

In some embodiments, controlling the ratio _of the combined content of _La2O3 and _{Gd2O3 ( La2O3} + _{Gd2O3 )} to _the content of _Nb2O5 ( _{( La2O3} + _{Gd2O3 )} / _Nb2O5 ) ₎ within the range of _3.5 to 15.0 helps the glass obtain a desired refractive index and Abbe number while reducing the thermal expansion coefficient of the glass and optimizing the light transmittance and Young's modulus. _Therefore , _{( La2O3 + Gd2O3 )} / _Nb2O5 is preferably _3.5 to _{15.0 ,} more preferably _{4.0 to 10.0 ,} further _preferably 5.0 to 8.0 _{, and even more preferably 5.5 to 6.5 .}

_TiO₂ increases the refractive index of glass, improves its stability, and reduces its density. However, if its content is too high, the glass's Abbe number will not meet design requirements, and the light transmittance of the glass will decrease. Therefore, the _TiO₂ content is 8-22%, preferably 10-20%, and even more preferably 13-18%.

In some embodiments, controlling the ratio _{of B2O3} to _{TiO2 ( B2O3} /TiO2 ₎ within the range of 0.1 to 1.0 can improve the glass's air bubble content and chemical stability, while preventing a decrease in the glass's light transmittance. Therefore, a _B2O3 /TiO2 _ratio of _0.1 to 1.0 is preferred, _0.2 to 0.8 is _more preferred, _{0.2 to 0.7 is} even more preferred, and _0.3 to 0.5 is even _more preferred _.

In some embodiments, the ratio of the combined content of _Gd2O3 , _{Nb2O5 ,} and _{TiO2 ( Gd2O3} + _Nb2O5 +TiO2 _{) to} the combined content of _{SiO2 and B2O3 ( SiO2} + _{B2O3 ) (Gd2O3+Nb2O5 + TiO2 )} /( _SiO2 + _B2O3 ) is controlled within the range of 1.0 to _8.0 , _which is beneficial to reducing _the density and thermal expansion coefficient of the glass and _improving the chemical stability and _light transmittance of the glass. Therefore, ( _Gd2O3 + _Nb2O5 + _TiO2 )/ ₍ SiO2+ _B2O3 ) is preferably _1.0 to 8.0, more preferably ( _Gd2O3 + _Nb2O5 + _TiO2 )/ _{( SiO2+B2O3) is 1.5 to 6.0, further preferably (Gd2O3+Nb2O5 + TiO2 ) / ( SiO2} + _{B2O3 )} is 2.0 to _5.0 , and _{even more preferably (Gd2O3 + Nb2O5 + TiO2 ) / ( SiO2} + _B2O3 ) is 2.5 to 4.0.

In some embodiments, the ratio of the combined content of _Gd2O3 and _TiO2 ( _Gd2O3 +TiO2 _{) to the} combined content of _La2O3 and _{Nb2O5 ( La2O3} + _Nb2O5 ) ( _Gd2O3 + _TiO2 )/( _La2O3 + _Nb2O5 ) is controlled within the range of _0.3 to _0.9 , which can optimize the density and abrasion resistance _{of the} glass and improve the anti _- devitrification performance and weather resistance _of the glass. Therefore, _{( Gd2O3} + _TiO2 )/( _La2O3 + _Nb2O5 ) is preferably 0.3-0.9, more preferably _{( Gd2O3} + _TiO2 )/ _{(La2O3+Nb2O5 )} is 0.35-0.8, more preferably ( _{Gd2O3 + TiO2} )/ _{( La2O3 + Nb2O5} ) is 0.4-0.7, and even _more preferably ( _{Gd2O3 + TiO2} ) _{/ ( La2O3 + Nb2O5 ) is} 0.45-0.6.

In some embodiments, the ratio of the combined content of _B2O3 and _{La2O3 ( B2O3 + La2O3 )} to the combined content of _Gd2O3 , _Nb2O5 , and _{TiO2 ( Gd2O3} + _Nb2O5 + _{TiO2) ( ( B2O3 + La2O3} )/ _{( Gd2O3} + _Nb2O5 + _TiO2 )) is controlled within the range of _0.7 to _{2.5 . This} can increase the bubble content of the glass and prevent deterioration in _the Young's modulus and hardness of the glass. Therefore, ( _B2O3 + _La2O3 )/( _Gd2O3 + _Nb2O5 + _TiO2 ) is preferably 0.7-2.5, more preferably ( _B2O3 + _{La2O3 )} / _{( Gd2O3 + Nb2O5} + _TiO2 ) is 0.8-2.0, more preferably ( _B2O3 + _La2O3 )/ _{( Gd2O3 + Nb2O5 + TiO2} ) is 0.9-1.7 _, and even more preferably _{( B2O3 + La2O3 )} / _{( Gd2O3 + Nb2O5 + TiO2 ) is 1.0-1.5} .

ZnO improves the devitrification resistance of glass, enhances the solubility of glass raw materials, and lowers the high-temperature viscosity and transition temperature of glass. However, excessive ZnO content increases the difficulty of glass molding and deteriorates thermal stability. Therefore, the ZnO content is preferably 0-5%, preferably 0-4%, and even more preferably 0.1-3%.

In some embodiments, controlling the ratio of _the combined ZnO and _Y₂O₃ content (ZnO+ _{Y₂O₃ )} to _{the Gd₂O₃} content ( ₍ ZnO+ _Y₂O₃ )/ _{Gd₂O₃ )} to below 0.8 is beneficial for improving the Young's modulus and anti _{-vitrification properties of the glass. Therefore, (ZnO+Y₂O₃)/Gd₂O₃ is preferably below 0.8} , and more preferably below 0.6. Furthermore, controlling the ₍ ZnO+ _Y₂O₃ )/ _{Gd₂O₃ ratio} to _within the range of 0.01 to 0.5 can further optimize _{the glass} 's bubbling properties. Therefore, the ₍ ZnO + Y ₂ O ₃ ) /Gd ₂ O _{3 ratio} is more preferably 0.01 to 0.5, _and even more preferably 0.05 to _0.3 .

In some embodiments, controlling the ratio of ZnO to the combined content _{of SiO₂ and B₂O₃ ( SiO₂ + B₂O₃ )} (ZnO/( _SiO₂ + _{B₂O₃ )} ) to below 0.8 helps improve the chemical stability and blistering of the glass. Therefore, ZnO/( _SiO₂ + _B₂O₃ ) is preferably below 0.8, and more preferably below 0.6. Furthermore, controlling the ZnO/ _{( SiO₂} + _B₂O₃ ) _ratio to within the range of 0.01 to _{0.5 can} further optimize _the thermal expansion coefficient of the glass. _Therefore , the ZnO/ ₍ SiO ₂ + B ₂ O ₃ ) ratio is more preferably 0.01 to 0.5, _and even more preferably 0.02 to 0.3.

Alkali earth metal oxides (RO) (RO is one or more of MgO, CaO, SrO, and BaO) can adjust the optical constants of glass and optimize its chemical stability. However, high RO content can reduce the glass's resistance to devitrification. Therefore, the RO content is limited to 0-6%, preferably 0-4%, and even more preferably 0-2%. In some embodiments, RO is preferably absent.

In some embodiments, controlling the ratio of RO to _Nb2O5 (RO/ _{Nb2O5 )} to below 0.8 helps reduce the thermal expansion coefficient of the glass and prevents degradation _of the glass's weather resistance _{and anti-vitrification properties. Therefore, RO/Nb2O5 is preferably} below _0.8 , more preferably _{below 0.5} , further preferably _below 0.3, and even more preferably _below 0.1.

In some embodiments, the ratio of the combined content _{of B2O3} , _La2O3 , _{Y2O3 ,} and RO _{( B2O3} + _La2O3 + _Y2O3 +RO ₎ to _the content of _{Gd2O3 (} ( _{B2O3 + La2O3} + _Y2O3 +RO)/ _{Gd2O3 )} is controlled within the range of 2.0 to 7.0, which can improve the weather resistance of _the glass and optimize the abrasion resistance and thermal expansion coefficient _{of the} glass. Therefore, ( _B2O3 + _La2O3 + _Y2O3 +RO)/ _Gd2O3 is _preferably 2.0-7.0, more preferably ( _B2O3 + _La2O3 + _Y2O3 +RO)/ _Gd2O3 is _{2.5-6.0 ,} more preferably ( _B2O3 + _{La2O3 +Y2O3 + RO} ) _{/ Gd2O3} is _3.0-4.6 , and _{even more preferably (B2O3+La2O3 + Y2O3 + RO )} / _{Gd2O3 is 3.5-4.5 .}

Alkali metal oxides ( _Rn₂O ) ( _Rn₂O is one or more of _Li₂O , _Na₂O , and _K₂O ) can lower the transition temperature of glass, adjust the optical constants and high-temperature viscosity of glass, and improve its meltability. However, high Rn₂O content can reduce the glass's devitrification resistance and chemical stability. Therefore, in the present invention, the _Rn₂O content is 0-5%, preferably 0-3%, and even more preferably 0-1%. In some embodiments, _Rn₂O is preferably absent.

_WO3 can increase the refractive index and mechanical strength of glass. However, if the _WO3 content exceeds 5%, the thermal stability of the glass decreases and its resistance to devitrification is reduced. Therefore, the upper limit of the _WO3 content is 5%, preferably 3%, and more preferably 1%. In some embodiments, it is further preferred that _WO3 be absent.

_{Ta₂O₅₅₅₅₅₅₅₅₅₅₅} has the effect of increasing the refractive index and improving the glass's resistance to devitrification. However, if its content is too _high , _{the glass} 's thermal stability decreases, the density increases, and _the optical constants become difficult to control within the desired range _. Furthermore, _{Ta₂O₅ ...}

_{Al2O3 can} improve the chemical stability of glass, but when its content exceeds 5%, the glass's solubility and light transmittance deteriorate. Therefore, in the present invention, _{the Al2O3} content is 0-5%, preferably 0-3%, and more preferably 0-1%. In some embodiments, it is further preferred that _{Al2O3 be} absent.

_{P2O5 can} improve the devitrification resistance of glass, but if its content is too high, the chemical stability _will decrease. Therefore, the content of _P2O5 is 0-4%, preferably 0-2%, more preferably 0-1%, and it is even more preferred that _P2O5 be _absent .

_GeO2 increases the refractive index and improves devitrification resistance, but excessive levels can reduce the chemical stability of glass. Furthermore, _GeO2 is very expensive compared to other components, so its use should be minimized for practical and cost reasons. Therefore, the _GeO2 content in the present invention is limited to 0-3%, preferably 0-2%, and even more preferably 0-1%. It is even more preferred that _GeO2 be absent.

In some embodiments, the ratio of the combined content of RO, _GeO2 , _Y2O3 , and _Ta2O5 (RO+ _{GeO2 +Y2O3+Ta2O5) to the content of La2O3 ((RO+GeO2+Y2O3+Ta2O5)/La2O3 ) ) is controlled below 0.3 to optimize the bubble degree} and abrasiveness of _the glass and prevent the deterioration _{of the} Young's modulus of the glass. Therefore _, (RO+ _GeO2 + _Y2O3 + _Ta2O5 )/ _La2O3 is preferably 0.3 or less, more preferably ( _RO + _GeO2 + _Y2O3 + _Ta2O5 )/ _La2O3 is _{0.2 or} less, further preferably (RO+ _{GeO2 + Y2O3} + _Ta2O5 )/ _La2O3 is _0.15 or less, and even more preferably ( _RO + _{GeO2 + Y2O3} + _{Ta2O5 ) / La2O3} is _{0.1 or less} .

The present invention includes 0-1% of one or more _{of Sb₂O₃} , _SnO₂ , and _CeO₂ as fining agents to enhance the clarification and degassing properties of the glass. The preferred fining agent content is 0-0.5%, and more preferably 0-0.2%. Due to the rational design of the component types and contents of the optical glass of the present invention, its degassing properties are excellent. Therefore, in some embodiments, it is further preferred that no fining agent be included. When _{the Sb2O3} content exceeds 1%, the glass tends to have reduced clarity. Its strong oxidizing effect also promotes corrosion of the platinum or platinum alloy vessels used to melt the glass and deteriorates the molding molds. Therefore, the present invention preferably contains _Sb2O3 in an amount of 0-1%, more preferably 0-0.5%, and even more preferably _0-0.2 %. It is even more preferred that the _glass contain no _Sb2O3 . _SnO2 can also serve as a fining agent, but when its content exceeds 1%, the glass tends to color more. Furthermore, when the glass is heated, softened, and then re-molded by molding, Sn can serve as a starting point for crystal nucleation, resulting in a tendency for devitrification. Therefore, the _SnO2 content of the present invention is preferably 0-1%, more preferably 0-0.5%, further preferably 0-0.2%, and even more preferably no _SnO2 is contained. The role and content ratio of _CeO2 are the same as those _{of SnO2} , and its content is preferably 0-1%, more preferably 0-0.5%, further preferably 0-0.2%, and even more preferably no _CeO2 is contained. <Components that should not be contained>

Even if oxides of transition metals such as V, Cr, Mn, Fe, Co, Ni, Cu, Ag, and Mo are present in the glass of the present invention, either singly or in combination, in small amounts, they can color the glass and absorb specific wavelengths in the visible light region, thereby reducing the present invention's ability to enhance visible light transmittance. Therefore, it is preferred that these oxides be substantially absent from the glass, particularly for optical glasses requiring transmittance at wavelengths in the visible light region.

In recent years, oxides of Th, Cd, Tl, Os, Be, and Se have been regulated as hazardous chemicals, necessitating environmental protection measures not only in glass manufacturing but also in processing and post-product disposal. Therefore, given the importance of environmental impact, it is preferable to virtually eliminate these oxides, except where they are unavoidable. This effectively eliminates environmentally polluting substances from optical glass. Therefore, the optical glass of the present invention can be manufactured, processed, and disposed of without requiring special environmental measures.

To achieve environmental friendliness, the optical glass of the present invention preferably does not contain As ₂ O ₃ and PbO.

The terms "does not contain" or "0%" used herein mean that the compound, molecule, element, or the like is not intentionally added as a raw material to the optical glass of the present invention. However, the raw materials and/or equipment used to produce the optical glass may contain certain unintentionally added impurities or components, which may be present in small or trace amounts in the final optical glass. Such situations are also within the scope of protection of the present patent.

The following describes the properties of the optical glass of the present invention. <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 (n _d ) of the optical glass of the present invention is 1.98, preferably 1.99, more preferably 2.00, further preferably 2.01, and even more preferably 2.03.

In some embodiments, the upper limit of the refractive index (n _d ) of the optical glass of the present invention is 2.15, preferably 2.10, and more preferably 2.07.

In some embodiments, the lower limit of the Abbe number (ν _d ) of the optical glass of the present invention is 22, preferably 23, more preferably 24, and further preferably 25.

In some embodiments, the upper limit of the Abbe number (ν _d ) of the optical glass of the present invention is 31, preferably 30, more preferably 29, and further preferably 28. <Thermal Expansion Coefficient>

The coefficient of thermal expansion of optical glass (α _{-30/70 °C} ) is measured at -30 to 70°C according to the method specified in GB/T7962.16-2010.

In some embodiments, the thermal expansion coefficient (α _{-30/70 °C} ) of the optical glass of the present invention is 90×10 ^-7 /K or less, preferably 80×10 ^-7 /K or less, and more preferably 75×10 ^-7 /K or less. <Acid 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 ( _DA ) of the optical glass of the present invention is Class 2 or higher, preferably Class 1.

The short-wavelength transmission spectral characteristics of the glass of the present invention are expressed using chromaticity ( _λ70 and _λ5 ). _λ70 refers to the wavelength at which the glass's transmittance reaches 70%. _λ70 is measured using 10±0.1mm thick glass with two parallel, optically polished opposing surfaces. The wavelength at which transmittance reaches 70% is measured. Spectral transmittance, or transmittance, is the value expressed as _Iout / _Iin when light with intensity Iin is incident perpendicularly on the surface of the glass and passes through the glass to _emerge from a single plane with intensity _Iout . This transmittance also includes surface reflection loss on the 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 _λ70 value means that the glass itself has minimal coloration and high light transmittance.

In some embodiments, the _λ70 of the optical glass of the present invention is below 480 nm, _preferably below 470 nm, and more preferably below 465 _nm .

In some embodiments, the optical glass of the present invention has a _λ5 of 390 nm or less, preferably 380 _nm or less, and more preferably 375 _nm or less.

The weather resistance (CR) test method for optical glass is as follows: the specimen is placed in a test chamber with a saturated water vapor environment at a relative humidity of 90%, alternating between 40°C and 50°C with an hourly cycle for 15 cycles. The weather resistance classification is determined based on the change in turbidity before and after the specimen is placed. The weather resistance classification is shown in Table 1:

Table 1. Category 1 2 3 4 a b c Turbidity increase △H (%) <0.3 0.3～1.0 1.0～2.0 2.0～4.0 4.0～6.0 ≥6.0

In some embodiments, the optical glass of the present invention has a weather resistance (CR) of Class 2 or higher, preferably Class 1. <Knoop Hardness>

The Knoop hardness ( _HK ) of optical glass is tested according to the test method specified in GB/T7962.18-2010.

In some embodiments, the Knoop hardness ( _HK ) of the optical glass of the present invention is 630×10 ⁷ Pa or greater, preferably 650×10 ⁷ Pa or greater, and more preferably 660×10 ⁷ Pa or greater. <Young's modulus>

Young's modulus (E) is calculated using the following formula using ultrasonic testing of longitudinal and transverse wave velocities. G=V _S ² ρ where: E is Young's modulus, Pa; G is shear modulus, Pa; _VT is transverse wave velocity, m/s; V _S is longitudinal wave velocity, m/s; ρ is glass density, g/cm ³ .

In some embodiments, the Young's modulus (E) of the optical glass of the present invention is 11,000 × 10 ⁷ Pa or more, preferably 12,000 × 10 ⁷ Pa or more, and more preferably 13,000 × 10 ⁷ Pa or more. <Bubble Degree>

The bubble content of optical glass is tested according to the method specified in GB/T7962.8-2010.

In some embodiments, the bubble level of the optical glass of the present invention is A-level or higher, preferably A0 _- level or higher, and more preferably _A00- level.

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, and more preferably 5.30 g/cm ³ or less.

The abrasion degree of optical glass ( _FA ) refers to the ratio of the wear amount of the sample to the wear amount (volume) of the standard sample (H-K9 glass) under exactly the same conditions, multiplied by 100, and is expressed as follows: _FA =V/ _V0 ×100=(W/ρ)/( _W0 / _ρ0 )×100 Where: V—volume wear amount of the sample being tested; _V0 —volume wear amount of the standard sample; W—mass wear amount of the sample being tested; _W0 —mass wear amount of the standard sample; ρ—density of the sample being tested; _ρ0 —density of the standard sample.

In some embodiments, the abrasiveness ( _FA ) of the optical glass of the present invention has a lower limit of 90, preferably 100, and more preferably 110.

In some embodiments, the upper limit of the abrasiveness ( _FA ) of the optical glass of the present invention is 140, preferably 130, and more preferably 123. [Manufacturing Method of Optical Glass]

The optical glass of the present invention is produced using conventional raw materials and processes, including but not limited to oxides, hydroxides, complex salts (such as carbonates, nitrates, sulfates), and boric acid. After mixing the ingredients according to conventional methods, the prepared charge is placed in a melting furnace (such as a platinum or platinum alloy crucible) at 1200-1450°C for melting. After clarification and homogenization, a homogeneous molten glass free of bubbles and undissolved matter is obtained. This molten glass is then cast in a mold and annealed. Those skilled in the art will be able to appropriately select the raw materials, process methods, and process parameters based on actual needs. [Glass Preforms and Optical Components]

The produced optical glass can be used to produce a glass preform using methods such as direct drop molding, grinding, or hot pressing. Specifically, the molten optical glass can be directly drop molded into a precision glass preform, or can be produced by mechanical processing such as grinding and lapping. Alternatively, a preform for press molding can be produced from the optical glass, followed by hot pressing and then grinding. It should be noted that the methods for producing a glass preform are not limited to the methods described above.

As described above, the optical glass of the present invention is useful for various optical elements and optical designs. It is particularly preferred to form a preform from the optical glass of the present invention and use the preform to perform re-hot pressing, precision stamping, etc. to produce optical elements such as lenses and prisms.

The glass preform and optical components of the present invention are both formed from the optical glass described above. The glass preform and optical components of the present invention possess the superior properties of optical glass, enabling the production of various optical components, such as lenses and prisms, with high optical value.

Examples of lenses include concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, and plano-concave lenses, with spherical or aspherical lens surfaces. [Optical Instruments]

Optical components formed from the optical glass of the present invention can be used to manufacture optical instruments such as photographic equipment, imaging equipment, projection equipment, display equipment, vehicle-mounted equipment, and monitoring equipment.

Examples <Optical Glass Examples>

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

This embodiment uses the above-mentioned optical glass manufacturing method to obtain optical glasses having the compositions shown in Tables 2 to 4. In addition, the properties of each glass were measured using the testing method described in the present invention, and the measurement results are shown in Tables 2 to 4.

Table 2. Example (wt%) 1# 2# 3# 4# 5# 6# 7# 8# SiO2 2.6 4.3 7.5 3.5 6.7 8.3 6.2 7.3 B2O3 6.3 7.2 3.7 8.2 5.5 2.5 6.1 4.6 La2O3 42 48.8 40.5 37.4 36.6 46.1 44.6 38.3 Y2O3 0.5 0.2 1.4 0.7 3.5 0 1.6 1.1 Gd2O3 18.2 11.3 7.6 8.5 10.6 16.2 9.8 13.6 Yb2O3 0 0 0 0 0 0 0 0 ZrO2 3.6 5.8 4.2 12.1 10.5 6.3 8.4 9.2 Nb2O5 12.5 10.2 13.6 4.3 6.2 5.5 8.3 7.6 TiO2 12.2 9.5 19.2 21.8 18.2 11.3 10.8 14.3 ZnO 0.6 0.1 0 0.7 0.2 0.8 2.2 1.5 MgO 0 0 1 0 0 0.5 0 0 CaO 0 0 0 0 0 0 1 0.5 SrO 0 0 0 0 0 0 0 0 BaO 0 0 0 0 1 0 0 0.5 Li2O 0 0.5 0 0 0 1 0 0 Na2O 1 0 0 2 0 0 0 0.5 K2O 0 0 0 0 0 0 0 0 WO3 0.5 0 0 0 0 0 0 1 Ta2O5 0 2 0 0.6 0 0 1 0 Al2O3 0 0 0 0 0 1.5 0 0 P2O5 0 0 0 0 1 0 0 0 GeO2 0 0 1.2 0 0 0 0 0 Sb2O3 0 0.1 0 0.2 0 0 0 0 SnO2 0 0 0.1 0 0 0 0 0 CeO2 0 0 0 0 0 0 0 0 total 100 100 100 100 100 100 100 100 SiO2+B2O3 8.9 11.5 11.2 11.7 12.2 10.8 12.3 11.9 La2O3+Y2O3+Gd2O3 60.7 60.3 49.5 46.6 50.7 62.3 56 53 RO/Nb2O5 0 0 0.07 0 0.16 0.09 0.12 0.13 (La2O3+Gd2O3)/Nb2O5 4.82 5.89 3.54 10.67 7.61 11.33 6.55 6.83 SiO2/B2O3 0.41 0.60 2.03 0.43 1.22 3.32 1.02 1.59 (ZnO+Y2O3)/Gd2O3 0.06 0.03 0.18 0.16 0.35 0.05 0.39 0.19 (SiO2+B2O3)/Gd2O3 0.49 1.02 1.47 1.38 1.15 0.67 1.26 0.88 ZnO/(SiO2+B2O3) 0.07 0.01 0 0.06 0.02 0.07 0.18 0.13 (SiO2+B2O3+La2O3)/ZrO2 14.14 10.40 12.31 4.06 4.65 9.03 6.77 5.46 B2O3/TiO2 0.52 0.76 0.19 0.38 0.30 0.22 0.56 0.32 (Gd2O3+Nb2O5+TiO2)/(SiO2+B2O3) 4.82 2.70 3.61 2.96 2.87 3.06 2.35 2.98 (Gd2O3+TiO2)/(La2O3+Nb2O5) 0.56 0.35 0.50 0.73 0.67 0.53 0.39 0.61 (B2O3+La2O3)/(Gd2O3+Nb2O5+TiO2) 1.13 1.81 1.09 1.32 1.20 1.47 1.75 1.21 (B2O3+La2O3)/(Gd2O3+SiO2) 2.32 3.59 2.93 3.80 2.43 1.98 3.17 2.05 (B2O+La2O3+Y2O3+RO)/Gd2O3 2.68 4.97 6.13 5.45 4.40 3.03 5.44 3.31 B2O/(ZrO2+Y2O3) 1.54 1.20 0.66 0.64 0.39 0.40 0.61 0.45 (RO+GeO2+Y2O3+Ta2O5)/La2O3 0.01 0.05 0.09 0.03 0.12 0.01 0.08 0.05 nd 2.0913 2.0824 2.0746 2.0131 2.0254 2.0347 2.0231 2.0424 νd 24.16 25.22 23.26 28.52 29.17 30.50 29.63 25.37 DA Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 CR Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 HK (×107Pa) 663 658 665 668 665 670 660 662 E (×107Pa) 12856 12473 13028 12936 12845 13124 12785 13325 ρ (g/cm3) 5.32 5.41 5.36 5.40 5.33 5.32 5.33 5.35 FA 126 127 103 106 112 113 125 116 Bubble degree (level) A00 A0 A0 A00 A00 A00 A0 A00 α-30/70℃ (×10-7/K) 80 78 77 78 75 76 73 74 λ70 (nm) 472 467 470 466 463 464 463 460 λ5 (nm) 381 375 380 375 372 372 375 368

Table 3. Example (wt%) 9# 10# 11# 12# 13# 14# 15# 16# SiO2 5.5 5.1 4.6 3.5 3.5 5.3 5.4 5 B2O3 8.3 4.7 6.5 4.4 8.5 6.2 6 5.7 La2O3 37 38.4 44.7 46.1 43.1 41.1 42.3 42.4 Y2O3 4.2 1.3 0.8 0.6 0.4 0.3 0.9 1.3 Gd2O3 14.8 11.2 10.5 12.4 13.3 12 11.7 12.5 Yb2O3 0 0 0 0 0 0 0 0 ZrO2 7.3 8.1 6.8 6.5 7.4 7.8 6.6 7.2 Nb2O5 10.2 11.4 8.3 9.5 7.7 11 10.3 10.5 TiO2 11.4 16.3 13.5 14 14.7 15.2 16 14.7 ZnO 0.3 0.5 3.8 1 1.4 1.1 0.8 0.7 MgO 0 0 0 2 0 0 0 0 CaO 0 1 0 0 0 0 0 0 SrO 0 0 0.5 0 0 0 0 0 BaO 0 2 0 0 0 0 0 0 Li2O 0 0 0 0 0 0 0 0 Na2O 0 0 0 0 0 0 0 0 K2O 1 0 0 0 0 0 0 0 WO3 0 0 0 0 0 0 0 0 Ta2O5 0 0 0 0 0 0 0 0 Al2O3 0 0 0 0 0 0 0 0 P2O5 0 0 0 0 0 0 0 0 GeO2 0 0 0 0 0 0 0 0 Sb2O3 0 0 0 0 0 0 0 0 SnO2 0 0 0 0 0 0 0 0 CeO2 0 0 0 0 0 0 0 0 total 100 100 100 100 100 100 100 100 SiO2+B2O3 13.8 9.8 11.1 7.9 12 11.5 11.4 10.7 La2O3+Y2O3+Gd2O3 56 50.9 56 59.1 56.8 53.4 54.9 56.2 RO/Nb2O5 0 0.26 0.06 0.21 0 0 0 0 (La2O3+Gd2O3)/Nb2O5 5.08 4.35 6.65 6.16 7.32 4.83 5.24 5.23 SiO2/B2O3 0.66 1.09 0.71 0.80 0.41 0.85 0.90 0.88 (ZnO+Y2O3)/Gd2O3 0.30 0.16 0.44 0.13 0.14 0.12 0.15 0.16 (SiO2+B2O3)/Gd2O3 0.93 0.88 1.06 0.64 0.90 0.96 0.97 0.86 ZnO/(SiO2+B2O3) 0.02 0.05 0.34 0.13 0.12 0.10 0.07 0.07 (SiO2+B2O3+La2O3)/ZrO2 6.96 5.95 8.21 8.31 7.45 6.74 8.14 7.38 B2O3/TiO2 0.73 0.29 0.48 0.31 0.58 0.41 0.38 0.39 (Gd2O3+Nb2O5+TiO2)/(SiO2+B2O3) 2.64 3.97 2.91 4.54 2.98 3.32 3.33 3.52 (Gd2O3+TiO2)/(La2O3+Nb2O5) 0.56 0.55 0.45 0.47 0.55 0.52 0.53 0.51 (B2O3+La2O3)/(Gd2O3+Nb2O5+TiO2) 1.24 1.11 1.59 1.41 1.45 1.24 1.27 1.28 (B2O3+La2O3)/(Gd2O3+SiO2) 2.23 2.64 3.39 3.18 3.07 2.73 2.82 2.75 (B2O+La2O3+Y2O3+RO)/Gd2O3 3.34 4.23 5 4.28 3.91 3.97 4.21 3.95 B2O/(ZrO2+Y2O3) 0.72 0.50 0.86 0.62 1.09 0.77 0.80 0.67 (RO+GeO2+Y2O3+Ta2O5)/La2O3 0.11 0.11 0.03 0.06 0.01 0.01 0.02 0.03 nd 2.0053 2.0508 2.0526 2.0633 2.0527 2.0266 2.0382 2.0512 νd 30.15 26.78 27.25 25.47 26.92 24.57 28.42 26.58 DA Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 CR Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 HK (×107Pa) 678 672 671 673 672 680 677 670 E (×107Pa) 13486 13212 13075 13368 13608 13223 13588 13542 ρ (g/cm3) 5.34 5.36 5.38 5.30 5.27 5.24 5.23 5.26 FA 120 119 107 117 115 113 120 118 Bubble degree (level) A00 A00 A0 A00 A00 A00 A00 A00 α-30/70℃ (×10-7/K) 66 73 75 73 70 74 65 64 λ70 (nm) 465 465 459 466 457 463 460 460 λ5 (nm) 376 376 370 374 369 374 371 368

Table 4. Example (wt%) 17# 18# 19# 20# twenty one# twenty two# twenty three# twenty four# SiO2 4.8 4.7 4.2 3.8 3.6 6.1 5.7 5.2 B2O3 5.5 5.9 4.8 7.3 7 6.5 6.3 5.8 La2O3 44 47.4 46.2 43 42 43.5 45.1 45.4 Y2O3 1 0.7 0.6 0.5 0.8 0.8 0.9 1 Gd2O3 13 10.4 12.5 12.2 13.7 10.5 11.6 12.4 Yb2O3 0 0 0 0 0 0 0 0 ZrO2 6.4 5.8 6.3 7.4 6.2 6.1 5.8 7 Nb2O5 9.6 9.8 8.6 10.2 11.1 10.4 9.2 8.7 TiO2 15.1 14.3 16.3 15.2 14.8 15.5 14.7 13.8 ZnO 0.6 1 0.5 0.4 0.8 0.6 0.7 0.7 MgO 0 0 0 0 0 0 0 0 CaO 0 0 0 0 0 0 0 0 SrO 0 0 0 0 0 0 0 0 BaO 0 0 0 0 0 0 0 0 Li2O 0 0 0 0 0 0 0 0 Na2O 0 0 0 0 0 0 0 0 K2O 0 0 0 0 0 0 0 0 WO3 0 0 0 0 0 0 0 0 Ta2O5 0 0 0 0 0 0 0 0 Al2O3 0 0 0 0 0 0 0 0 P2O5 0 0 0 0 0 0 0 0 GeO2 0 0 0 0 0 0 0 0 Sb2O3 0 0 0 0 0 0 0 0 SnO2 0 0 0 0 0 0 0 0 CeO2 0 0 0 0 0 0 0 0 total 100 100 100 100 100 100 100 100 SiO2+B2O3 10.3 10.6 9 11.1 10.6 12.6 12 11 La2O3+Y2O3+Gd2O3 58 58.5 59.3 55.7 56.5 54.8 57.6 58.8 RO/Nb2O5 0 0 0 0 0 0 0 0 (La2O3+Gd2O3)/Nb2O5 5.94 5.90 6.83 5.41 5.02 5.19 6.16 6.64 SiO2/B2O3 0.87 0.80 0.88 0.52 0.51 0.94 0.90 0.90 (ZnO+Y2O3)/Gd2O3 0.12 0.16 0.09 0.07 0.12 0.13 0.14 0.14 (SiO2+B2O3)/Gd2O3 0.79 1.02 0.72 0.91 0.77 1.20 1.03 0.89 ZnO/(SiO2+B2O3) 0.06 0.09 0.06 0.04 0.08 0.05 0.06 0.06 (SiO2+B2O3+La2O3)/ZrO2 8.48 10 8.76 7.31 8.48 September 20 9.84 8.06 B2O3/TiO2 0.36 0.41 0.29 0.48 0.47 0.42 0.43 0.42 (Gd2O3+Nb2O5+TiO2)/(SiO2+B2O3) 3.66 3.25 4.16 3.39 3.74 2.89 2.96 3.17 (Gd2O3+TiO2)/(La2O3+Nb2O5) 0.52 0.43 0.53 0.52 0.54 0.48 0.48 0.48 (B2O3+La2O3)/(Gd2O3+Nb2O5+TiO2) 1.31 1.54 1.36 1.34 1.24 1.37 1.45 1.47 (B2O3+La2O3)/(Gd2O3+SiO2) 2.78 3.53 3.05 3.14 2.83 3.01 2.97 2.91 (B2O+La2O3+Y2O3+RO)/Gd2O3 3.88 5.19 4.13 4.16 3.64 4.84 4.51 4.21 B2O/(ZrO2+Y2O3) 0.74 0.91 0.70 0.92 1 0.94 0.94 0.73 (RO+GeO2+Y2O3+Ta2O5)/La2O3 0.02 0.01 0.01 0.01 0.02 0.02 0.02 0.02 nd 2.0527 2.0607 2.0477 2.0438 2.0517 2.0496 2.0525 2.0536 νd 26.69 27.06 27.35 26.55 26.37 26.85 27.16 27.08 DA Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 CR Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 Category 1 HK (×107Pa) 682 673 671 670 677 674 673 675 E (×107Pa) 13607 13493 13567 13526 13486 13667 13485 13568 ρ (g/cm3) 5.28 5.38 5.29 5.22 5.24 5.27 5.26 5.25 FA 116 106 115 117 116 109 113 115 Bubble degree (level) A ₀₀ A ₀₀ A ₀₀ A ₀₀ A ₀₀ A ₀₀ A ₀₀ A ₀₀ α-30/70℃ (×10-7/K) 67 73 72 65 68 63 68 64 λ70 (nm) 455 457 464 461 460 457 460 458 λ5 (nm) 365 368 372 370 372 366 371 367 <Glass Preform Example>

The glasses obtained in Optical Glass Examples 1 to 24 can be used, for example, by grinding, hot pressing, precision stamping, or other molding methods to produce preforms for various lenses, such as concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, and plano-concave lenses, as well as prisms. <Optical Element Examples>

The preforms obtained from the above-mentioned glass preform embodiments are annealed to reduce the internal stress of the glass and fine-tune the refractive index so that the optical properties such as the refractive index reach the desired values.

Each preform is then ground and polished to produce various lenses and prisms, including concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, and plano-concave lenses. The surfaces of the resulting optical components can also be coated with an antireflection film. <Optical Instrument Example>

The optical elements produced by the above-mentioned optical element embodiments are optically designed and formed into optical components or optical assemblies using one or more optical elements. The optical components can be used in, for example, imaging equipment, sensors, microscopes, medical technology, digital projection, communications, optical communication technology/information transmission, optics/illumination in the automotive field, photolithography technology, excimer lasers, chips, computer chips, and integrated circuits and electronic components including such circuits and chips.

Claims (18)

An optical glass characterized in that its composition, expressed in weight percentage, comprises: _{SiO2 + B2O3} : 3-18%; _La2O3 + _{Y2O3 +} Gd2O3: 45-65%; _ZrO2 : _3-13 %; _Nb2O5 : _3-15 %; _TiO2 : 8-22%, wherein _the ( _La2O3 + _Gd2O3 ) _{/ Nb2O5 ratio} is 3.5-15.0; _B2O3 : 1-10% _{; and the} ( _B2O3 + _La2O3 + _{Y2O3 +} RO)/ _{Gd2O3 ratio} is _2.0-4.6 , wherein RO is one or more of MgO, CaO, SrO, _and BaO. The optical glass according to claim 1, wherein the components thereof, expressed in weight percentage, further comprise: ZnO: 0-5%; and/or RO: 0-6%; and/or _Rn2O : 0-5%; and/or _WO3 : 0-5%; and _/ or _Ta2O5 : 0-5%; and/or _Al2O3 : 0-5%; and/or _Yb2O3 : 0-8%; and/or _GeO2 : 0-3%; and/or _P2O5 : 0-4%; and/or a _{fining agent} : 0-1%, wherein RO is one or more of MgO, CaO, SrO, _and BaO; _Rn2O is one or more of _Li2O , _Na2O , and _K2O ; and the fining agent is one or more _{of Sb2O3} , _SnO2 , and _CeO2 . An optical glass characterized by containing _ZrO2 , _Nb2O5 , _{and TiO2} as essential components, wherein the composition _, expressed in weight percentage, comprises 3-18% _SiO2 + _B2O3 and 45-65% _La2O3 + _Y2O3 + _Gd2O3 , wherein ( _La2O3 + _Gd2O3 )/ _Nb2O5 is 3.5-15.0, and the optical glass has a refractive index _nd of 1.98 or greater _, an _Abbe number _vd of 22-31, _{and a} thermal _expansion coefficient α _{at -30/70 ° C} of 90 _× ^10-7 /K or _less ; _B2O3 : 1-10%; _{( B2O3 + La2O3} + _Y2O3 + RO)/ _Gd2O3 ; ₃ is 2.0-4.6, and the RO is one or more of MgO, CaO, SrO, and BaO. The optical glass as claimed in claim 3, wherein the composition thereof is expressed in weight percentage and further comprises: ZrO ₂ : 3-13%; and/or Nb ₂ O ₅ : 3-15%; and/or TiO ₂ : 8-22%; and/or ZnO: 0-5%; and/or RO: 0-6%; and/or Rn ₂ O: 0-5%; and/or WO ₃ : 0-5%; and/or Ta ₂ O ₅ : 0-5%; and/or Al ₂ O ₃ : 0-5%; and/or Yb ₂ O ₃ : 0-8%; and/or GeO ₂ : 0-3%; and/or P ₂ O ₅ : 0-4%; and/or a fining agent: 0-1%, wherein the RO is one or more of MgO, CaO, SrO, and BaO, and the Rn ₂ O is Li ₂ O, Na ₂ O, or K _{2 O.} The clarifier is one or more of Sb ₂ O ₃ , SnO ₂ , and CeO ₂ . The optical glass according to any one of claims 1 to 4, wherein the composition thereof, expressed in weight percentage, satisfies one or more of the following 14 conditions: 1) (La ₂ O ₃ +Gd ₂ O ₃ )/Nb ₂ O ₅ is 4.0 to 10.0; 2) SiO ₂ /B ₂ O ₃ is 0.4 to 4.0; 3) (ZnO + Y ₂ O ₃ )/Gd ₂ O ₃ is 0.8 or less; 4) (SiO ₂ +B ₂ O ₃ )/Gd ₂ O ₃ is 0.3 to 2.5; 5) ZnO/(SiO ₂ +B ₂ O ₃ ) is 0.8 or less; 6) (SiO ₂ +B ₂ O ₃ +La ₂ O ₃ )/ZrO ₂ is 4.0 to 15.0; 7) B ₂ O ₃ /TiO 3 is 0. ₂ is 0.1 to 1.0; 8) (Gd ₂ O ₃ +Nb ₂ O ₅ +TiO ₂ )/(SiO ₂ +B ₂ O ₃ ) is 1.0 to 8.0; 9) (Gd ₂ O ₃ +TiO ₂ )/(La ₂ O ₃ +Nb ₂ O ₅ ) is 0.3 to 0.9; 10) (B ₂ O ₃ +La ₂ O ₃ )/(Gd ₂ O ₃ +Nb ₂ O ₅ +TiO ₂ ) is 0.7～2.5; 11) (B ₂ O ₃ +La ₂ O ₃ )/(Gd ₂ O ₃ +SiO ₂ ) is 1.5～5.5; 12) B ₂ O ₃ / (ZrO ₂ +Y ₂ O ₃ ) is 0.2~2.5; 13) RO/Nb ₂ O ₅ is 0.8 or less; 14) (RO + GeO ₂ + Y ₂ O ₃ + Ta ₂ O ₅ ) / La ₂ O ₃ is 0.3 or less, and the RO is one or more of MgO, CaO, SrO, and BaO. The optical glass according to any one of claims 1 to 4, wherein the composition thereof, expressed in weight percentage, satisfies one or more of the following 15 conditions: 1) (La ₂ O ₃ + Gd ₂ O ₃ )/Nb ₂ O ₅ is 5.0 to 8.0; 2) SiO ₂ /B ₂ O ₃ is 0.5 to 3.0; 3) (ZnO + Y ₂ O ₃ )/Gd ₂ O ₃ is 0.6 or less; 4) (SiO ₂ + B ₂ O ₃ )/Gd ₂ O ₃ is 0.4 to 2.0; 5) ZnO/(SiO ₂ + B ₂ O ₃ ) is 0.6 or less; 6) (SiO ₂ + B ₂ O ₃ + La ₂ O ₃ )/ZrO ₂ is 5.0 to 12.0; 7) B ₂ O ₃ /TiO 3 is 0.6 or less; ₂ is 0.2～0.8; 8) (Gd ₂ O ₃ +Nb ₂ O ₅ +TiO ₂ )/(SiO ₂ +B ₂ O ₃ ) is 1.5～6.0; 9) (Gd ₂ O ₃ +TiO ₂ )/(La ₂ O ₃ +Nb ₂ O ₅ ) is 0.35～0.8; 10) (B ₂ O ₃ +La ₂ O ₃ )/(Gd ₂ O ₃ +Nb ₂ O ₅ +TiO ₂ ) is 0.8～2.0; 11) (B ₂ O ₃ +La ₂ O ₃ )/(Gd ₂ O ₃ +SiO ₂ ) is 2.0～4.0; 12) B ₂ O ₃ / (ZrO ₂ +Y ₂ O ₃ ) is 0.4~2.0; 13) RO/Nb ₂ O ₅ is 0.5 or less; 14) ( _B2O3 + _La2O3 + _Y2O3 + _RO )/ _Gd2O3 is _2.5-4.6 ; 15) (RO _{+ GeO2 + Y2O3} + _Ta2O5 )/ _La2O3 is _0.2 or _less , and the _RO is one or more of MgO, CaO, SrO, and BaO. The optical glass according to any one of claims 1 to 4, wherein the composition thereof, expressed in weight percentage, satisfies one or more of the following 15 conditions: 1) (La ₂ O ₃ +Gd ₂ O ₃ )/Nb ₂ O ₅ is 5.5-6.5; 2) SiO ₂ /B ₂ O ₃ is 0.6-2.0; 3) (ZnO + Y ₂ O ₃ )/Gd ₂ O ₃ is 0.01-0.5; 4) (SiO ₂ +B ₂ O ₃ )/Gd ₂ O ₃ is 0.5-1.5; 5) ZnO/(SiO ₂ +B ₂ O ₃ ) is 0.01-0.5; 6) (SiO ₂ +B ₂ O ₃ +La ₂ O ₃ )/ZrO ₂ is 6.5-10.0; 7) B ₂ O ₃ /TiO 3 is 0. ₂ is 0.2～0.7; 8) (Gd ₂ O ₃ +Nb ₂ O ₅ +TiO ₂ )/(SiO ₂ +B ₂ O ₃ ) is 2.0～5.0; 9) (Gd ₂ O ₃ +TiO ₂ )/(La ₂ O ₃ +Nb ₂ O ₅ ) is 0.4～0.7; 10) (B ₂ O ₃ +La ₂ O ₃ )/(Gd ₂ O ₃ +Nb ₂ O ₅ +TiO ₂ ) is 0.9～1.7; 11) (B ₂ O ₃ +La ₂ O ₃ )/(Gd ₂ O ₃ +SiO ₂ ) is 2.3～3.3; 12) B ₂ O ₃ / (ZrO ₂ +Y ₂ O ₃ ) is 0.5~1.5; 13) RO/Nb ₂ O ₅ is 0.3 or less; 14) ( _B2O3 + _La2O3 + _Y2O3 + _RO )/ _Gd2O3 is _3.0-4.6 ; 15) (RO _{+ GeO2 + Y2O3} + _Ta2O5 )/ _La2O3 is _0.15 or _less , and the _RO is one or more of MgO, CaO, SrO, and BaO. The optical glass according to any one of claims 1 to 4, wherein the composition thereof, expressed in weight percentage, satisfies one or more of the following 14 conditions: 1) SiO ₂ /B ₂ O ₃ is 0.7 to 1.2; 2) (ZnO + Y ₂ O ₃ ) /Gd ₂ O ₃ is 0.05 to 0.3; 3) (SiO ₂ + B ₂ O ₃ ) /Gd ₂ O ₃ is 0.7 to 1.2; 4) ZnO / (SiO ₂ + B ₂ O ₃ ) is 0.02 to 0.3; 5) (SiO ₂ + B ₂ O ₃ +La ₂ O ₃ ) /ZrO ₂ is 7.5 to 9.0; 6) B ₂ O ₃ /TiO ₂ is 0.3 to 0.5; 7) (Gd ₂ O ₃ +Nb ₂ O ₅ +TiO ₂ ) / (SiO ₂ +B ₂ O ₃ ) is 2.5 to 4.0; 8) (Gd ₂ O ₃ +TiO ₂ )/(La ₂ O ₃ +Nb ₂ O ₅ ) is 0.45 to 0.6; 9) (B ₂ O ₃ +La ₂ O ₃ )/(Gd ₂ O ₃ +Nb ₂ O ₅ +TiO ₂ ) is 1.0 to 1.5; 10) (B ₂ O ₃ +La ₂ O ₃ )/(Gd ₂ O ₃ +SiO ₂ ) is 2.5 to 3.2; 11) B ₂ O ₃ / (ZrO ₂ +Y ₂ O ₃ ) is 0.6 to 1.0; 12) RO/Nb ₂ O ₅ is 0.1 or less; 13) (B ₂ O ₃ +La ₂ O ₃ +Y ₂ O ₃ +RO)/Gd ₂ O ₃ is 3.5 to 4.5; 14) (RO + GeO ₂ + Y ₂ O ₃ + Ta ₂ O ₅ ) /La ₂ O ₃ is 0.1 or less, and the RO is one or more of MgO, CaO, SrO, and BaO. The optical glass according to any one of claims 1 to 4, wherein the components thereof are expressed in weight percentages, wherein: SiO ₂ + B ₂ O ₃ : 5-15%; and/or La ₂ O ₃ + Y ₂ O ₃ + Gd ₂ O ₃ : 50-63%; and/or ZrO ₂ : 4-11%; and/or Nb ₂ O ₅ : 5-13%; and/or TiO ₂ : 10-20%; and/or ZnO: 0-4%; and/or RO: 0-4%; and/or Rn ₂ O: 0-3%; and/or WO ₃ : 0-3%; and/or Ta ₂ O ₅ : 0-3%; and/or Al ₂ O ₃ : 0-3%; and/or Yb ₂ O ₃ : 0-5%; and/or GeO ₂ : 0-2%; and/or P ₂ O ₅ : 0-2%; and/or clarifier: 0-0.5%, wherein RO is one or more of MgO, CaO, SrO, and BaO, _Rn2O is one or more of _Li2O , _Na2O , and _K2O , and the clarifier is one or more of _Sb2O3 , _SnO2 , _{and CeO2} . The optical glass according to any one of claims 1 to 4, wherein the components thereof are expressed in weight percentages, wherein: SiO ₂ + B ₂ O ₃ : 7-13%; and/or La ₂ O ₃ + Y ₂ O ₃ + Gd ₂ O ₃ : 52-60%; and/or ZrO ₂ : 6-10%; and/or Nb ₂ O ₅ : 7-12%; and/or TiO ₂ : 13-18%; and/or ZnO: 0.1-3%; and/or RO: 0-2%; and/or Rn ₂ O: 0-1%; and/or WO ₃ : 0-1%; and/or Ta ₂ O ₅ : 0-1%; and/or Al ₂ O ₃ : 0-1%; and/or Yb ₂ O ₃ : 0-1%; and/or GeO ₂ : 0-1%; and/or P ₂ O ₅ : 0-1%; and/or clarifier: 0-0.2%, wherein RO is one or more of MgO, CaO, SrO, and BaO, _Rn2O is one or more of _Li2O , _Na2O , and _K2O , and the clarifier is one or more of _Sb2O3 , _SnO2 , _{and CeO2} . The optical glass according to any one of claims 1 to 4, wherein the components thereof are expressed in weight percentages, wherein: SiO ₂ : 1-10%; and/or La ₂ O ₃ : 35-50%; and/or Y ₂ O ₃ : 0-6%; and/or Gd ₂ O ₃ : 6-20%. The optical glass according to any one of claims 1 to 4, wherein the components thereof are expressed in weight percentages, wherein: SiO ₂ : 3-7%; and/or B ₂ O ₃ : 4-8%; and/or La ₂ O ₃ : 41-46%; and/or Y ₂ O ₃ : 0.1-3%; and/or Gd ₂ O ₃ : 11-15%. The optical glass as described in any one of claims 1 to 4, wherein its composition does _not contain _WO3 ; and/or does not contain _Ta2O5 ; and/or does not contain RO; and _/ or does not contain _Rn2O ; and/or does not contain _P2O5 ; and _/ or does not contain _Al2O3 ; and/or does not contain _GeO2 ; and/or does not _{contain Yb2O3} , wherein RO is one or more of MgO, CaO, SrO, and BaO, and _Rn2O is one or more of _Li2O , _Na2O , and _K2O . The optical glass according to any one of claims 1 to 4, wherein the optical glass has a refractive index _nd of 1.99 or greater; and/or an Abbe number _vd of 23 to 30; and/or a thermal expansion coefficient α _{-30/70 °C} of 80× ^10-7 /K or less; and/or an acid resistance stability _DA of Class 2 or greater; and/or a _λ70 of 480 nm or less; and/or a _λ5 of 390 nm or less; and/or a weather resistance CR of Class 2 or greater; and/or a Knoop hardness _HK of 630× ¹⁰⁷ Pa or greater; and/or a Young's modulus E of 11000× ¹⁰⁷ Pa or greater; and/or a bubble degree of Class A or greater; and/or a density ρ of 5.50 g/cm3 or ^less ; and/or an abrasion resistance _FA of 90 to 140. The optical glass according to any one of claims 1 to 4, wherein the optical glass has a refractive index _nd of 2.01 to 2.10, and/or an Abbe number _vd of 25 to 28; and/or a thermal expansion coefficient α _{-30/70 °C} of 75× ^10-7 /K or less; and/or an acid resistance stability _DA of Class 1; and/or a _λ70 of 465 nm or less; and/or a _λ5 of 375 nm or less; and/or a weather resistance CR of Class 1; and/or a Knoop hardness _HK of 660× ¹⁰⁷ Pa or more; and/or a Young's modulus E of 13000× ¹⁰⁷ Pa or more; and/or a bubble degree of _A00 ; and/or a density ρ of 5.30 g/cm3 or ^less ; and/or an abrasion resistance _FA of 110 to 123. A glass preform is characterized in that it is made of the optical glass as described in any one of claims 1 to 15. An optical element is characterized in that it is made of the optical glass as described in any one of claims 1 to 15, or is made of the glass preform as described in claim 16. An optical instrument, characterized by comprising the optical glass as described in any one of claims 1 to 15 and/or the optical element as described in claim 17.