Optical glass and optical element

Abstract

This invention provides an optical glass with a low glass transition temperature, low dispersion, and excellent thermal stability. The optical glass of this invention has the following glass composition, expressed as cation percent: S 6+ Content exceeding 0.0% but below 30.0%, Al 3+ Content exceeding 0.0% but below 30.0%, P 5+ Content of 5.0% or more and 50.0% or less, Li + Content of 0.0% to 51.0% and Na + Content of 0.0% or more and 44.0% or less, K + The content is above 0.0% and below 45.0%, Li + Na + K + and Cs + Total content R + For a percentage above 5.0%, Be 2+ Mg 2+ Ca 2+ 、Sr 2+ And Ba 2+ The total content is set as R. 2+ R 2+ Compared to Al 3+ With R 2+ The total content of cation ratio (R) 2+ / (Al 3+ +R 2+ The anion content is 0.56% or less, and the glass composition is as follows (expressed as anion percentage): O 2‑ The content is above 10.0% and below 95.0%, F ‑ The content is 10.0% or more and 90.0% or less, and the external transmittance of the above optical glass at a wavelength of 500nm to 1000nm is 80% or more when converted to a thickness of 10.0mm.

Description

Technical Field

[0001] This invention relates to optical glass and optical components. Background Technology

[0002] For example, patent document 1 discloses an optical glass with a low glass transition temperature.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: WO2003 / 037813 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] Glass with a low glass transition temperature can be molded at low temperatures. Considering factors such as less deterioration of the molding die caused by heating and the ability to use molding dies with low heat resistance and low cost, molding at low temperatures is preferred.

[0008] In projection optical systems such as camera optical systems and projectors, chromatic aberration can be compensated and the optical system can be miniaturized by combining lenses with different dispersion properties to form a combined lens. Low dispersion is generally easy to achieve with plastic lenses; therefore, optical glass with low dispersion is useful as a material for optical components in projection optical systems such as camera optical systems and projectors.

[0009] In view of the above, the inventors studied optical glasses with low glass transition temperature and low dispersion, and found that further improvements in thermal stability can be expected.

[0010] One embodiment of the present invention aims to provide an optical glass with a low glass transition temperature, low dispersion, and excellent thermal stability.

[0011] Problem Solving Methods

[0012] One embodiment of the present invention relates to an optical glass having, in a glass composition expressed as cations%,

[0013] S 6+ Content exceeding 0.0% cations and below 30.0% cations,

[0014] Al 3+ Content exceeding 0.0% cations and below 30.0% cations,

[0015] P 5+ The content is 5.0% or more and 50.0% or less of cationic content.

[0016] Li + The content is ≥0.0% cations and ≤51.0% cations.

[0017] Na + The content is ≥0.0% cations and ≤44.0% cations.

[0018] K + The content is ≥0.0% cations and ≤45.0% cations.

[0019] Li + Na + K + and Cs + Total content R + It is 5.0% or more of cations.

[0020] Be 2+ Mg 2+ Ca 2+ 、Sr 2+ And Ba 2+ The total content is set as R. 2+ R 2+ Compared to Al 3+ With R 2+ The total content of cation ratio (R) 2+ / (Al 3+ +R 2+ The value is below 0.56.

[0021] In the glass composition expressed as anion %

[0022] O 2- The content is ≥10.0% anion and ≤95.0% anion.

[0023] F - The content is 10.0% or more and 90.0% or less of anions.

[0024] Furthermore, the external transmittance of the optical glass at the wavelengths of 500nm to 1000nm, converted to a thickness of 10.0mm, is over 80%.

[0025] The optical glass described above, by having the aforementioned glass composition, can have a low glass transition temperature and low dispersion, and can exhibit excellent thermal stability.

[0026] The effects of the invention

[0027] According to one embodiment of the present invention, an optical glass with a low glass transition temperature, low dispersion, and excellent thermal stability can be provided. Furthermore, according to another embodiment of the present invention, an optical element incorporating the optical glass can be provided. Detailed Implementation

[0028] Optical Glass

[0029] In this invention and this specification, unless otherwise specified, the content and total content of cationic components are expressed as cationic % and the content and total content of anionic components are expressed as anionic % unless otherwise specified.

[0030] Here, "cation%" is a value calculated as "(number of cations of interest / total number of cations in the glass composition) × 100", which represents the molar percentage of the amount of cations of interest relative to the total amount of the cation composition.

[0031] In addition, "anion%" is a value calculated as "(number of anions of interest / total number of anions in the glass composition) × 100", which represents the molar percentage of the amount of anions of interest relative to the total amount of anion components.

[0032] The molar ratio of the contents of the cationic components is equal to the ratio of the contents of the cationic component of interest, expressed as cations (%).

[0033] The content of each component can be quantified by known methods, such as inductively coupled plasma atomic emission spectrometry (ICP-AES), inductively coupled plasma mass spectrometry (ICP-MS), and ion chromatography.

[0034] Regarding cationic components, such as Al 3+ P 5+ This indicates the valence of the cationic component (e.g., Al). 3+ The price is +3, P 5+ The valence (+5) is a value determined by convention, similar to how Al, P, etc., are expressed as Al2O3, P2O5, etc., based on oxides. Regarding the expression of A as an oxide... m O n The composition of (A represents cation, O represents oxygen, and m and n are stoichiometric integers) is represented as A. s+ Where s = 2n / m. Therefore, for example, when analyzing and quantifying the composition of glass, the valence of the cationic components does not need to be analyzed. The same applies to the anionic components; when analyzing and quantifying the composition of glass, the valence of the anionic components does not need to be analyzed.

[0035] Furthermore, in this invention and this specification, the content of a constituent element being 0.0%, 0.00%, not containing, or not introduced means that the constituent element is substantially not contained, and the content of the constituent element is below the level of impurities, which means, for example, less than 0.01%.

[0036] In this invention and this specification, "thermal stability" refers to the degree to which crystals do not easily precipitate when molten glass solidifies.

[0037] Hereinafter, the glass transition temperature will sometimes be expressed as Tg.

[0038] The optical glass (sometimes simply referred to as "glass") described above will be explained in more detail below.

[0039] <Glass Composition>

[0040] The glass composition of the aforementioned optical glass, expressed as cations (%), will be described below.

[0041] From the perspectives of reducing the Tg of glass, maintaining the refractive index and low dispersion, and improving thermal stability, S 6+ The content exceeds 0%, preferably 0.5% or more, and more preferably in the following order: 1.0% or more, 1.2% or more, 1.3% or more, 1.4% or more, 1.5% or more, 1.6% or more, 1.7% or more, 1.8% or more, 1.9% or more, 2.0% or more, 2.1% or more, 2.2% or more, 2.3% or more, 2.4% or more, 2.5% or more, 2.6% or more, 2.7% or more, 2.8% or more, 2.9% or more, and 3.0% or more.

[0042] Furthermore, considering the need to maintain refractive index, thermal stability, and suppress the rise in liquid phase temperature, S 6+ The content is 30.0% or less, preferably 29.0% or less, and more preferably in the order of 28.0% or less, 27.0% or less, 26.0% or less, 25.0% or less, 24.0% or less, 23.0% or less, 22.0% or less, 21.0% or less, 20.0% or less, 19.0% or less, 18.0% or less, 17.0% or less, 16.0% or less, 15.0% or less, and 14.0% or less.

[0043] From the perspectives of increasing the refractive index while maintaining low dispersion, and from the perspectives of improving the thermal stability and maintaining the chemical durability of glass, Al 3+ The content exceeds 0.0%, preferably 1.0% or more, and more preferably in the order of 2.0% or more, 3.0% or more, 4.0% or more, 5.0% or more, 6.0% or more, 7.0% or more, 8.0% or more, 9.0% or more, 10.0% or more, and 11.0% or more.

[0044] Furthermore, from the perspective of suppressing the rise of Tg, Al 3+The content is 30.0% or less, preferably 29.0% or less, and more preferably in the order of 28.0% or less, 27.0% or less, 26.0% or less, 25.0% or less, 24.0% or less, 23.0% or less, 22.0% or less, 21.0% or less, 20.0% or less, 19.0% or less, and 18.0% or less.

[0045] From the perspective of maintaining low dispersion and improving the thermal stability of glass, P 5+ The content is 5.0% or more, preferably 7.0% or more, and more preferably in the order of 9.0% or more, 11.0% or more, 13.0% or more, 14.0% or more, 15.0% or more, 16.0% or more, and 17.0% or more.

[0046] Furthermore, from the perspectives of maintaining the refractive index, improving the thermal stability of the glass, and suppressing the decline in chemical durability, P 5+ The content is 50.0% or less, preferably 48.0% or less, and more preferably in the order of 46.0% or less, 44.0% or less, 42.0% or less, 40.0% or less, 38.0% or less, 37.0% or less, 36.0% or less, 35.0% or less, 34.0% or less, 33.0% or less, and 32.0% or less.

[0047] From the perspectives of increasing refractive index while maintaining low dispersion, as well as lowering the glass's Tg, improving its meltability, and reducing its specific gravity, Li + The content is 0.0% or more, preferably 1.0% or more, and more preferably in the order of 2.0% or more, 4.0% or more, 5.5% or more, 7.0% or more, 8.5% or more, 10.0% or more, 12.0% or more, 13.5% or more, 15.0% or more, 16.5% or more, 17.0% or more, 18.5% or more, and 20.0% or more.

[0048] Furthermore, from the perspective of improving the thermal stability of glass and suppressing the decline in chemical durability, Li + The content is 51.0% or less, preferably 48.0% or less, and more preferably in the order of 45.0% or less, 43.0% or less, 41.0% or less, 40.0% or less, 39.0% or less, 38.0% or less, 37.0% or less, 36.0% or less, 35.0% or less, 34.0% or less, 33.0% or less, 32.0% or less, and 31.0% or less.

[0049] From the perspectives of maintaining refractive index, maintaining low dispersion, lowering the glass's Tg, improving its melting point, and reducing its specific gravity, Na... +The content is 0.0% or more, preferably 1.0% or more, and more preferably in the order of 2.0% or more, 3.0% or more, 4.0% or more, 5.0% or more, 6.0% or more, 7.0% or more, 8.0% or more, and 9.0% or more.

[0050] Furthermore, from the perspective of improving the thermal stability of glass and inhibiting the reduction of chemical durability, Na + The content is 44.0% or less, preferably 42.0% or less, and more preferably in the order of 40.0% or less, 38.0% or less, 36.0% or less, 34.0% or less, 32.0% or less, 30.0% or less, 28.0% or less, 26.0% or less, 24.0% or less, 22.0% or less, 20.0% or less, and 19.0% or less.

[0051] From the perspectives of maintaining refractive index, maintaining low dispersion, lowering the glass's Tg, improving its melting point, and reducing its specific gravity, K + The content is 0.0% or more, preferably 1.0% or more, and more preferably in the order of 2.0% or more, 3.0% or more, 4.0% or more, 5.0% or more, and 6.0% or more.

[0052] Furthermore, from the perspectives of improving the thermal stability of glass, suppressing the decline in chemical durability, and reducing specific gravity, K + The content is preferred to be 45.0% or less, in the following order: 43.0% or less, 40.0% or less, 38.0% or less, 36.0% or less, 34.0% or less, 32.0% or less, 30.0% or less, 28.0% or less, 26.0% or less, 25.0% or less, 24.0% or less, 23.0% or less, 22.0% or less, 21.0% or less, 20.0% or less, 19.0% or less, 18.0% or less, 17.0% or less, 16.0% or less, and 15.0% or less.

[0053] From the perspectives of maintaining low dispersion, low Tg of the glass, low specific gravity, and lower liquidus temperature, Li + Na + K + and Cs + Total content R + The content is 5.0% or more, preferably 10.0% or more, and more preferably in the order of 15.0% or more, 20.0% or more, 23.0% or more, 25.0% or more, 28.0% or more, 30.0% or more, 33.0% or more, 35.0% or more, 37.0% or more, 40.0% or more, and 42.0% or more.

[0054] Furthermore, considering the need to maintain low dispersion, preserve the thermal stability of the glass, and inhibit the degradation of chemical durability, Li+ Na + K + and Cs + Total content R + Preferably, it is 65.0% or less, and more preferably in the order of 64.0% or less, 63.0% or less, 62.0% or less, 61.0% or less, 60.0% or less, and 59.0% or less.

[0055] Cs + The content can be 0.0%, or more than 0.0%, or even exceed 0.0%. From the perspective of reducing the Tg of glass and improving its melting properties, Cs... + The content can be 0.0% or more, preferably 0.1% or more, and more preferably in the order of 0.2% or more, 0.3% or more, 0.4% or more, 0.5% or more, and 0.6% or more.

[0056] Furthermore, from the perspective of improving the thermal stability of glass and inhibiting the decline in chemical durability, Cs + The content is preferably 10.0% or less, and more preferably in the order of 8.0% or less, 6.0% or less, 4.0% or less, 2.0% or less, 1.5% or less, and 1.0% or less.

[0057] From the perspective of suppressing the rise of Tg and maintaining the thermal stability of glass, Be 2+ Mg 2+ Ca 2+ 、Sr 2+ And Ba 2+ The total content is set as R. 2+ In the aforementioned optical glass, R 2+ Compared to Al 3+ With R 2+ The total content of cation ratio (R) 2+ / (Al 3+ +R 2+ The value is 0.56 or less, preferably 0.55 or less, and more preferably in the order of 0.54 or less, 0.53 or less, 0.52 or less, 0.51 or less, 0.50 or less, 0.49 or less, 0.48 or less, 0.47 or less, 0.46 or less, 0.45 or less, 0.44 or less, 0.43 or less, 0.42 or less, 0.41 or less, 0.40 or less, 0.39 or less, 0.38 or less, and 0.37 or less.

[0058] In addition, the cation ratio (R) 2+ / (Al 3+ +R 2+The value can be 0.00 or more than 0.00. From the viewpoint of reducing the Tg of the glass and improving the meltability of the glass, it is preferred to be 0.01 or more, and more preferably in the order of 0.02 or more and 0.03 or more.

[0059] Be 2+ The content can be 0.0%, above 0.0%, or exceeding 0.0%. From the perspective of maintaining refractive index, maintaining low dispersion, suppressing the rise of Tg, and maintaining the thermal stability of the glass, Be... 2+ The content is preferably 15.0% or less, more preferably 10.0% or less, and further preferably in the order of 5.0% or less, 2.5% or less, 1.5% or less, 1.0% or less, and 0.5% or less.

[0060] Mg 2+ The content can be 0.0%, above 0.0%, or greater than 0.0%. From the perspective of maintaining refractive index, maintaining low dispersion, suppressing the rise of Tg, and maintaining the thermal stability of the glass, Mg... 2+ The content is preferably 15.0% or less, more preferably 14.0% or less, and further preferably in the order of 13.0% or less, 12.0% or less, 11.0% or less, and 10.0% or less.

[0061] Ca 2+ The content can be 0.0%, above 0.0%, or greater than 0.0%. From the perspective of maintaining refractive index, maintaining low dispersion, suppressing the rise of Tg, and maintaining the thermal stability of the glass, Ca... 2+ The content is preferably 15.0% or less, more preferably 14.0% or less, and further preferably in the order of 13.0% or less, 12.0% or less, 11.0% or less, 10.0% or less, 9.0% or less, 8.0% or less, 7.0% or less, 6.0% or less, and 5.0% or less.

[0062] Sr 2+ The content can be 0.0%, above 0.0%, or greater than 0.0%. From the perspective of maintaining refractive index, maintaining low dispersion, suppressing the rise of Tg, and maintaining the thermal stability of the glass, Sr... 2+ The content is preferably 10.0% or less, more preferably 9.0% or less, and further preferably in the order of 8.0% or less, 7.0% or less, 6.0% or less, 5.0% or less, and 4.0% or less.

[0063] Ba 2+ The content can be 0.0%, above 0.0%, or greater than 0.0%. From the perspectives of maintaining refractive index, maintaining low dispersion, improving glass meltability, suppressing Tg rise, and maintaining glass thermal stability, Ba... 2+The content is preferably 10.0% or less, more preferably 9.0% or less, and further preferably in the order of 8.0% or less, 7.0% or less, 6.0% or less, 5.0% or less, 4.0% or less, 3.0% or less, and 2.0% or less.

[0064] Be 2+ Mg 2+ Ca 2+ 、Sr 2+ And Ba 2+ Total content R 2+ It can be 0.0%, above 0.0%, or greater than 0.0%. From the perspective of maintaining refractive index, maintaining low dispersion, suppressing the rise of Tg, and maintaining the thermal stability of the glass, the total content R... 2+ Preferably, it is 20.0% or less, more preferably 19.0% or less, and further preferably in the order of 18.0% or less, 17.0% or less, 16.0% or less, 15.0% or less, 14.0% or less, 13.0% or less, 12.0% or less, 11.0% or less, and 10.0% or less.

[0065] Zn 2+ The content can be 0.0%, above 0.0%, or greater than 0.0%. Zn 2+ Zn plays a role in maintaining refractive index and improving thermal stability, but if it is present in excess, it tends to increase dispersion. Considering the above points, Zn... 2+ The content is preferably 20.0% or less, more preferably 19.0% or less, and further preferably in the order of 18.0% or less, 17.0% or less, 16.0% or less, 15.0% or less, 14.0% or less, 13.0% or less, 12.0% or less, 11.0% or less, and 10.0% or less.

[0066] Zr 4+ The content can be 0.0%, above 0.0%, or greater than 0.0%. Zr 4+ Zr is a component that increases the refractive index, but if it is present in excess, it tends to increase dispersion and lead to an increase in chromatic ag (Tg). Considering the above points, Zr... 4+ The content is preferably 10.0% or less, more preferably 9.0% or less, and further preferably in the order of 8.0% or less, 7.0% or less, 6.0% or less, 5.0% or less, 4.0% or less, 3.0% or less, and 2.0% or less.

[0067] From the perspectives of maintaining low dispersion, further improving the thermal stability of glass, further reducing the Tg of glass, and improving the melting properties of glass, P 5+ Content relative to Al 3+ With P 5+ The total content of cation ratio (P)5+ / (Al 3+ +P 5+ Preferably, the value is 0.30 or higher, more preferably 0.35 or higher, and further preferred in the order of 0.40 or higher, 0.45 or higher, and 0.50 or higher.

[0068] Furthermore, from the viewpoint of maintaining refractive index and chemical durability, the cation ratio (P) 5+ / (Al 3+ +P 5+ Preferably, the value is 0.85 or less, more preferably 0.83 or less, and further preferably in the order of 0.81 or less, 0.80 or less, 0.79 or less, 0.78 or less, 0.77 or less, 0.76 or less, 0.75 or less, 0.74 or less, 0.73 or less, 0.72 or less, and 0.71 or less.

[0069] From the perspectives of increasing refractive index, further reducing the Tg of the glass, and improving the meltability of the glass, Li + Content relative to R + With R 2+ The total cation ratio (Li + / (R + +R 2+ Preferably, the value is 0.00 or higher, more preferably 0.05 or higher, and further preferred in the order of 0.10 or higher, 0.13 or higher, 0.15 or higher, 0.17 or higher, 0.20 or higher, 0.23 or higher, 0.25 or higher, 0.27 or higher, 0.30 or higher, 0.33 or higher, 0.35 or higher, 0.37 or higher, and 0.40 or higher.

[0070] Furthermore, from the perspective of further reducing the Tg of glass and improving its meltability, the cation ratio (Li) + / (R + +R 2+ Preferably, the value is 1.00 or less, more preferably 0.95 or less, and further preferably in the order of 0.92 or less, 0.90 or less, 0.88 or less, 0.85 or less, 0.83 or less, 0.80 or less, 0.78 or less, 0.75 or less, 0.72 or less, 0.70 or less, 0.67 or less, 0.65 or less, 0.63 or less, and 0.60 or less.

[0071] From the perspectives of maintaining low dispersion, further reducing the Tg of the glass, improving the melting point of the glass, and reducing its specific gravity, R + Compared to Al 3+ With P 5+ The total content of cation ratio (R) + / (Al 3+ +P 5+Preferably, it is 0.93 or higher, more preferably 0.95 or higher, and even more preferably 0.97 or higher, 0.99 or higher, 1.01 or higher, 1.03 or higher, 1.05 or higher, 1.07 or higher, 1.09 or higher, 1.11 or higher, 1.13 or higher, 1.14 or higher, 1.15 or higher, or 1.16 or higher.

[0072] Furthermore, from the perspective of maintaining refractive index, maintaining low dispersion, and maintaining the thermal stability of glass, the cation ratio (R... + / (Al 3+ +P 5+ Preferably, the value is 2.00 or less, more preferably 1.98 or less, and further preferably in the order of 1.96 or less, 1.94 or less, 1.92 or less, 1.90 or less, 1.88 or less, 1.87 or less, 1.86 or less, and 1.85 or less.

[0073] From the perspectives of maintaining low dispersion, further reducing the Tg of the glass, improving the melting point of the glass, and reducing its specific gravity, Li + With K + The total content relative to Al 3+ With P 5+ The total content of cation ratio ((Li + +K + ) / (Al 3+ +P 5+ Preferably, the value is 0.56 or higher, more preferably 0.58 or higher, and further preferred in the order of 0.60 or higher, 0.62 or higher, 0.64 or higher, 0.66 or higher, 0.68 or higher, 0.70 or higher, 0.72 or higher, 0.74 or higher, 0.76 or higher, 0.78 or higher, and 0.80 or higher.

[0074] Furthermore, from the perspective of maintaining refractive index, maintaining low dispersion, and maintaining thermal stability, the cation ratio ((Li) + +K + ) / (Al 3+ +P 5+ Preferably, the value is 1.40 or less, more preferably 1.38 or less, and further preferably in the order of 1.36 or less, 1.34 or less, 1.32 or less, 1.30 or less, 1.28 or less, 1.27 or less, 1.26 or less, and 1.25 or less.

[0075] From the perspective of further reducing the Tg of glass and improving its melting properties, Li + with Na + The total content relative to Li + With K + The total content of cation ratio ((Li + +Na +) / (Li + +K + Preferably, the value is 0.50 or higher, more preferably 0.55 or higher, and further preferred in the order of 0.60 or higher, 0.65 or higher, 0.70 or higher, 0.75 or higher, 0.80 or higher, 0.85 or higher, 0.86 or higher, 0.87 or higher, 0.88 or higher, 0.89 or higher, and 0.90 or higher.

[0076] From the perspective of further reducing the Tg of glass and improving its meltability, the cation ratio ((Li) + +Na + ) / (Li + +K + Preferably, the value is 1.59 or less, more preferably 1.57 or less, and further preferably in the order of 1.55 or less, 1.53 or less, 1.51 or less, 1.49 or less, 1.47 or less, 1.45 or less, 1.43 or less, 1.41 or less, 1.39 or less, 1.37 or less, 1.35 or less, 1.33 or less, 1.31 or less, 1.29 or less, 1.28 or less, 1.27 or less, 1.26 or less, 1.25 or less, and 1.24 or less.

[0077] Pb, As, Cd, Tl, Be, and Se are all toxic, therefore, it is preferable to avoid including these elements in the glass, that is, not to introduce these elements into the glass as glass components.

[0078] U, Th, and Ra are all radioactive elements. Therefore, it is preferable to avoid including these elements in the glass, that is, not to introduce these elements into the glass as a glass component.

[0079] V, Cr, Mn, Fe, Co, Ni, Cu, Pr, Nd, Pm, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Ce may increase the coloration of the glass or become sources of fluorescence; therefore, these elements are not preferred for use in glass as optical components. It is therefore preferable that these elements are not present, i.e., that they are not introduced into the glass as a component.

[0080] Sb and Sn are optional elements that function as clarifying agents.

[0081] Based on the mass fraction (%) of Sb₂O₃ when the mass of the glass is set to 100, the Sb content of the aforementioned optical glass can be, for example, 0.40% or less, 0.20% or less, 0.10% or less, 0.05% or less, 0.02% or less, or 0.01% or less. On the other hand, based on the mass fraction (%) of Sb₂O₃ when the mass of the glass is set to 100, the Sb content can be 0.00% or more, or it can be 0.00%.

[0082] Based on the mass fraction (%) of SnO2 when the mass of the glass is set to 100, the Sn content of the aforementioned optical glass can be, for example, 0.40% or less, 0.20% or less, 0.10% or less, 0.05% or less, 0.02% or less, or 0.01% or less. On the other hand, based on the mass fraction (%) of SnO2 when the mass of the glass is set to 100, the Sn content can be 0.00% or more, or it can be 0.00%.

[0083] The above explains the cationic components. Next, the anionic components will be explained.

[0084] The aforementioned optical glass contains at least O 2- and F - As an anionic component.

[0085] From the perspective of increasing the refractive index of glass and improving its thermal stability, O 2- The content is 10.0% or more, preferably 15.0% or more, and more preferably in the following order: 17.5% or more, 20.0% or more, 22.5% or more, 25.0% or more, 27.5% or more, 30.0% or more, 32.5% or more, 35.0% or more, 37.5% or more, 40.0% or more, 42.5% or more, 45.0% or more, 48.0% or more, 49.0% or more, 50.0% or more, 51.0% or more, 52.0% or more, 53.0% or more, 54.0% or more, 55.0% or more, 56.0% or more, 57.0% or more, 58.0% or more, and 59.0% or more.

[0086] Furthermore, from the perspective of maintaining low dispersion and suppressing the rise of the glass's Tg, O 2- The content is 95.0% or less, preferably 88.5% or less, and more preferably in the order of 86.0% or less, 83.5% or less, 82.0% or less, 81.0% or less, 80.0% or less, 79.0% or less, 78.0% or less, and 77.0% or less.

[0087] From the perspective of maintaining the glass's low dispersion and low Tg, F - The content is 10.0% or more, preferably 11.00% or more, and more preferably in the order of 12.00% or more, 13.00% or more, 14.00% or more, 15.00% or more, 16.00% or more, 17.00% or more, 18.00% or more, 19.00% or more, 20.00% or more, 21.00% or more, 22.00% or more, and 23.00% or more.

[0088] Furthermore, from the perspective of improving the thermal stability of glass and suppressing glass volatilization during melting, F -The content is 90.0% or less, preferably 85.0% or less, and more preferably in the following order: 80.0% or less, 75.0% or less, 70.0% or less, 65.0% or less, 63.0% or less, 60.0% or less, 57.0% or less, 55.0% or less, 54.0% or less, 52.0% or less, 50.0% or less, 49.0% or less, 48.0% or less, 47.0% or less, 46.0% or less, 45.0% or less, 44.0% or less, and 43.0% or less.

[0089] As for O 2- and F - Other anionic components, such as Cl, can be exemplified. - ,Br - and I - .

[0090] Cl - The content can be, for example, 0.0%, more than 0.0%, more than 0.0%, more than 0.10%, more than 0.20%, and can also be, for example, less than 5.0%, less than 4.0%, less than 3.0%, less than 2.0%, less than 1.0%, or less than 0.50%.

[0091] Br - The content can be, for example, 0.0%, more than 0.0%, more than 0.0%, more than 0.10%, more than 0.20%, or, for example, less than 5.0%, less than 4.0%, less than 3.0%, less than 2.0%, less than 1.0%, or less than 0.5%.

[0092] I - The content can be, for example, 0.0%, more than 0.0%, more than 0.0%, more than 0.10%, more than 0.20%, or, for example, less than 5.0%, less than 4.0%, less than 3.0%, less than 2.0%, less than 1.0%, or less than 0.5%.

[0093] <Properties of Glass>

[0094] (Abbe number νd)

[0095] The optical glass described above exhibits low dispersion due to its glass composition. The Abbe number νd, an indicator of dispersion, is expressed using the refractive indices nd, nF, and nC under d-rays, F-rays, and C-rays, respectively, as νd = (nd - 1) / (nF - nC). From the viewpoint of its usefulness as a material for optical elements, the Abbe number νd of the optical glass is preferably 70.00 or higher, more preferably 70.50 or higher, and further preferably in the order of 71.00 or higher, 71.50 or higher, 72.00 or higher, 72.50 or higher, and 73.00 or higher. Furthermore, the Abbe number νd of the optical glass can, for example, be 82.00 or lower.

[0096] (Refractive index nd)

[0097] From the viewpoint of its usefulness as a material for optical elements, the refractive index nd of the aforementioned optical glass can, for example, be 1.420 or higher, 1.425 or higher, 1.430 or higher, 1.435 or higher, 1.440 or higher, 1.445 or higher, 1.446 or higher, 1.447 or higher, 1.448 or higher, 1.449 or higher, or 1.450 or higher. Alternatively, it can be 1.510 or lower, 1.505 or lower, 1.500 or lower, 1.4950 or lower, 1.490 or lower, 1.489 or lower, 1.488 or lower, 1.487 or lower, 1.486 or lower, 1.485 or lower, 1.484 or lower, 1.483 or lower, or 1.482 or lower. In this invention and this specification, "refractive index" refers to "refractive index nd," which is the refractive index at a wavelength of 587.56 nm.

[0098] (Glass transition temperature Tg)

[0099] The optical glass described above, by having the aforementioned glass composition, can have a low glass transition temperature. The glass transition temperature Tg of the aforementioned optical glass is preferably 350°C or less, more preferably 340°C or less, and further preferably in the order of 330°C or less, 320°C or less, 310°C or less, 300°C or less, 290°C or less, 280°C or less, 270°C or less, and 260°C or less. Furthermore, the glass transition temperature Tg of the aforementioned optical glass can, for example, be 150°C or more, 160°C or more, 170°C or more, 180°C or more, 190°C or more, or 200°C or more. The glass transition temperature Tg is determined by the method described later.

[0100] (proportion)

[0101] From the viewpoint of reducing the weight of optical components, it is preferable that the optical glass has a low specific gravity. The specific gravity of the optical glass can be, for example, 3.10 or less, 3.05 or less, 3.00 or less, 2.95 or less, 2.90 or less, or 2.85 or less. Alternatively, the specific gravity of the optical glass can be, for example, 2.55 or more; the lower the specific gravity, the more preferred. Therefore, there is no particular limitation on the lower limit.

[0102] (Transmittance characteristics)

[0103] The aforementioned optical glass exhibits an external transmittance of 80% or more when converted to a thickness of 10.0 mm within the wavelength range of 500 nm to 1000 nm. "An external transmittance of 80% or more when converted to a thickness of 10.0 mm within the wavelength range of 500 nm to 1000 nm" means that the external transmittance converted to a thickness of 10.0 mm is 80% or more but less than 100% within the entire wavelength range of 500 nm to 1000 nm. Optical glass with this transmittance characteristic is useful as a material for optical components. For example, by manufacturing it without Cu... 2+ Glass with cationic components can achieve the aforementioned transmittance characteristics.

[0104] The transmittance characteristics of the glass described above were determined using the following method.

[0105] The glass sample was processed into a plane with parallel surfaces that had been optically polished, and the external transmittance was measured at wavelengths of 500–1000 nm. The external transmittance also includes the light reflection loss at the sample surface.

[0106] In addition, if the glass being measured is not the glass of the thickness to be converted, the thickness of the glass can be set as d, and the transmittance at each wavelength λ can be converted using the following formula A, and the transmittance characteristics can be obtained through the conversion.

[0107] Equation A: T(λ)=(1-R(λ)) 2 ×exp(log e ((T0(λ) / 100) / (1-R(λ)) 2 )×d / d0)×100

[0108] In Equation A, T(λ): converted transmittance at wavelength λ (%), T0(λ): measured transmittance at wavelength λ (%), d: converted thickness (mm), d0: glass thickness (mm), R(λ)=((n(λ)-1) / (n(λ)+1)) 2Let n(λ) represent the reflectance at wavelength λ, and n(λ) represent the refractive index at wavelength λ. The refractive index n(λ) at wavelength λ is determined according to Japanese Industrial Standard (JIS) JISB 7071-1 "Method for Determination of Refractive Index of Optical Glass - Part 1: Minimum Deflection Angle Method" for each wavelength.

[0109] <Methods for Manufacturing Optical Glass>

[0110] The aforementioned optical glass can be obtained as follows: Phosphates, fluorides, oxides, carbonates, sulfates, nitrates, hydroxides, etc., are weighed and mixed as raw materials to obtain the desired glass composition. This mixture is thoroughly mixed to form a masterbatch, which is then heated, melted, degassed, and stirred in a melting vessel to produce a uniform, bubble-free molten glass. This molten glass is then shaped to obtain the optical glass. Specifically, a known melting method can be used for its production.

[0111] [Glass raw materials for pressure forming, optical component blanks, and their manufacturing methods]

[0112] Another embodiment of the present invention relates to:

[0113] Glass raw materials for pressure forming of the aforementioned optical glass; and

[0114] Optical component blanks containing the aforementioned optical glass.

[0115] According to another embodiment of the present invention, the following is also provided:

[0116] A method for manufacturing glass raw materials for pressure forming, comprising the process of forming the aforementioned optical glass into glass raw materials for pressure forming;

[0117] A method for manufacturing optical component blanks, comprising the step of pressurizing the aforementioned glass raw material for pressurizing optical glass using a pressurizing mold to produce optical component blanks; and

[0118] A method for manufacturing optical element blanks, comprising the process of forming the aforementioned optical glass into optical element blanks.

[0119] Optical element blanks refer to optical element base materials that are similar in shape to the target optical element, and have been coated with polishing material (a surface layer that is removed by polishing) and, if necessary, abrasive material (a surface layer that is removed by grinding). The optical element is then finished by grinding and polishing the surface of the optical element blank. In one embodiment, the optical element blank can be produced by pressing molten glass obtained by melting an appropriate amount of the aforementioned glass (called the direct press method). In another embodiment, the optical element blank can also be produced by solidifying the molten glass obtained by melting an appropriate amount of the aforementioned glass.

[0120] In another embodiment, an optical element blank can be produced by manufacturing a glass raw material for pressure molding and by press molding the manufactured glass raw material for pressure molding.

[0121] The pressure forming of glass raw materials for pressure forming can be carried out by a known method of applying pressure to the heated and softened glass raw materials using a pressure forming mold. Both heating and pressure forming can be performed in the atmosphere. By annealing after pressure forming to reduce internal strain in the glass, a uniform optical element blank can be obtained.

[0122] Regarding glass raw materials for pressure forming, in addition to raw materials called glass gobs that are supplied directly in their original state for pressure forming of optical component blanks, this also includes raw materials that have undergone machining such as cutting, grinding, and polishing, and have been processed by glass gobs before being supplied for pressure forming. Cutting methods include methods such as: forming a groove on the surface of a glass plate to be cut using a method called scribing; applying localized pressure from the back side of the grooved side towards the grooved portion; and cutting the glass plate using a cutting blade. Grinding and polishing methods include tumbler polishing.

[0123] Glass raw materials for pressure forming can be produced, for example, by casting molten glass into a mold and shaping it into a glass plate, and then cutting the glass plate into multiple glass sheets. Alternatively, a suitable amount of molten glass can be shaped to produce glass droplets for pressure forming. Optical component blanks can also be produced by reheating and softening the glass droplets for pressure forming and then pressing them. The method of producing optical component blanks by reheating, softening, and pressing glass is called the reheat press method, as opposed to the direct pressing method.

[0124] Optical components and their manufacturing methods

[0125] Another embodiment of the present invention relates to:

[0126] Optical components that include the aforementioned optical glass.

[0127] The aforementioned optical element is manufactured using the aforementioned optical glass. In the aforementioned optical element, a coating of one or more layers, such as an anti-reflective film, can be formed on the glass surface.

[0128] Additionally, according to one embodiment of the present invention, the following can also be provided:

[0129] A method for manufacturing an optical element, comprising the steps of grinding and / or polishing the aforementioned optical element blank to produce an optical element.

[0130] In the above-described manufacturing method for optical elements, machining processes such as grinding and polishing can be performed using known methods. By thoroughly cleaning and drying the surface of the optical element after machining, optical elements with high internal and surface quality can be obtained. This results in an optical element formed from the aforementioned optical glass. Examples of optical elements include spherical lenses, aspherical lenses, microlenses, and various prisms.

[0131] Furthermore, optical elements formed from the aforementioned optical glass are also suitable for use as lenses constituting joined optical elements. Examples of joined optical elements include elements formed by joining lenses together (joined lenses) and elements formed by joining lenses and prisms. For example, joined optical elements can be manufactured by precisely machining the joining surfaces of the two optical elements to be joined in such a way that their shapes are reversed (e.g., spherical polishing), applying an ultraviolet-curing adhesive for bonding the joined lenses, bonding them together, and then irradiating them with ultraviolet light through the lens to cure the adhesive, thereby manufacturing a joined optical element. Multiple elements to be joined can be manufactured separately using various types of glass with different Abbe numbers (νd) and then joined together, thereby producing an element suitable for compensating chromatic aberration.

[0132] Example

[0133] The present invention will now be described in more detail with reference to the embodiments. However, the present invention is not limited to the implementation methods shown in the embodiments.

[0134] [Example 1]

[0135] <Sample No. 1~88>

[0136] To achieve the glass composition shown in the table below, appropriate phosphates, fluorides, nitrates, sulfates, carbonates, hydroxides, oxides, boric acids, etc., were used as raw materials for introducing each component. The raw materials were weighed, thoroughly mixed, and the blending raw materials were prepared.

[0137] The raw materials were placed in a platinum crucible and heated in a furnace set at 700–1100°C for 90 minutes. After the molten glass was stirred and homogenized, it was poured into a preheated mold and allowed to cool naturally to near the glass transition temperature. It was then immediately placed in an annealing furnace and held at around the glass transition temperature for about 30 minutes. After that, it was slowly cooled at a rate of -30°C / hour for 4 hours, and then allowed to cool naturally to room temperature in the furnace. This yielded the optical glasses No. 1–88 shown in the table below.

[0138] [Comparative Example A, Comparative Example B]

[0139] To achieve the glass composition shown in the table below, appropriate phosphates, fluorides, nitrates, sulfates, carbonates, hydroxides, oxides, boric acids, etc., were used as raw materials for introducing each component. The raw materials were weighed, thoroughly mixed, and the blending raw materials were prepared.

[0140] The raw materials were placed in a platinum crucible and heated in a furnace set at 700–1100°C for 90 minutes. After the molten glass was stirred and homogenized, it was poured into a preheated mold and allowed to cool naturally to near the glass transition temperature. It was then immediately placed in an annealing furnace and held at approximately the glass transition temperature for about 30 minutes. Afterward, it was slowly cooled at a rate of -30°C / hour for 4 hours, and then allowed to cool naturally to room temperature in the furnace. This yielded the optical glasses of Comparative Examples A and B shown in the table below. Comparative Example A corresponds to Example 33 of WO2003 / 037813 (Patent Document 1), and Comparative Example B corresponds to Example 35 of WO2003 / 037813 (Patent Document 1).

[0141] <Physical Property Evaluation>

[0142] The physical properties of the optical glasses shown in the following table were determined using the methods described below.

[0143] (1) Refractive index nd, Abbe number νd

[0144] For each optical glass, the refractive index nd and Abbe number νd were measured using the standard refractive index measurement method of the Japan Optical Glass Manufacturers Association. Regarding Comparative Example A, since the glass was devitrified, the refractive index nd and Abbe number νd could not be measured.

[0145] (2) Glass transition temperature Tg

[0146] The glass was thoroughly crushed in a mortar and pestle to form a sample. A platinum cell was used as the sample container. The glass transition temperature Tg was determined using a differential scanning calorimeter (DSC3300SA) manufactured by NETZSCH JAPAN, with the heating rate set to 10 °C / min.

[0147] (3) Specific gravity

[0148] The specific gravity was determined using the Archimedes method.

[0149] (4) Transmittance characteristics

[0150] Test pieces were cut from the obtained glass, and both sides were mirror polished to form parallel, optically polished planes. After the thickness reached 10.0 mm, the external transmittance at wavelengths of 500–1000 nm was measured using a spectrophotometer.

[0151] In any of the samples No. 1 to 88, Comparative Example A and Comparative Example B, it was confirmed that the external transmittance at wavelengths of 500 nm to 1000 nm was 80% or more and 100% or less when the thickness was 10.0 mm.

[0152] <Evaluation of Thermal Stability>

[0153] For samples No. 1 to 88, Comparative Example A and Comparative Example B, respectively, in order to form the glass composition shown in the table below, the corresponding phosphates, fluorides, nitrates, sulfates, carbonates, hydroxides, oxides, boric acids, etc. were used as raw materials for introducing each component. The raw materials were weighed, thoroughly mixed, and prepared into formulation raw materials.

[0154] The raw materials were placed in a platinum crucible and heated in a furnace set at 700–1100°C for 90 minutes. After the molten glass was stirred and homogenized, it was cast into a molding die, shaped, and slowly cooled to obtain a block-shaped glass sample.

[0155] The obtained glass samples were observed for crystallization using an optical microscope. The magnification of the optical microscope was set to 40–100x. If no crystals were observed in the glass block, it was classified as A. The average crystal density was [missing information - likely a value] per 1 cm. 3 If more than one but less than 15 crystals are confirmed, it is classified as B, with an average density of 1 cm. 3 If more than 16 but less than 40 crystals are confirmed, it is classified as C. This is based on an average density of crystals per 1cm. 3If more than 40 crystals are confirmed, the glass is classified as D. Regarding A, B, and C, thermal stability increases in the order C→B→A, with A having the highest thermal stability. If the order is A, B, and C, then the number of crystals in the glass is within an acceptable range for internal quality during manufacturing. Glass classified as D lacks thermal stability and is considered to have poor internal quality during manufacturing.

[0156] As shown in the table below, the glass samples No. 1 to 88 were confirmed to have excellent thermal stability (judgment result A, B or C).

[0157]

[0158]

[0159]

[0160]

[0161]

[0162]

[0163]

[0164]

[0165]

[0166]

[0167]

[0168]

[0169]

[0170]

[0171]

[0172]

[0173]

[0174]

[0175] (Example 2)

[0176] Glass blocks (glass droplets) for pressure forming were fabricated using the various glasses obtained in Example 1. The glass droplets were heated and softened in the atmosphere, and then pressed and formed using a pressure forming mold to produce lens blanks (optical element blanks). The lens blanks were removed from the pressure forming mold, annealed, and subjected to machining processes including polishing to produce spherical lenses formed from the various glasses produced in Example 1.

[0177] (Example 3)

[0178] The molten glass produced in Example 1 was press-formed using a pressure forming mold to produce a lens blank (optical element blank). The produced lens blank was removed from the pressure forming mold, annealed, and subjected to machining processes including polishing to produce spherical lenses formed from the various types of glass produced in Example 1.

[0179] (Example 4)

[0180] An annealing process was performed on the glass block (optical element blank) made by solidifying the molten glass produced in Example 1, followed by machining including polishing, to produce spherical lenses formed from various types of glass produced in Example 1.

[0181] Finally, the above implementation methods are summarized.

[0182] [1] An optical glass having, in a glass composition expressed as cations%,

[0183] S 6+ Content exceeding 0.0% cations and below 30.0% cations,

[0184] Al 3+ Content exceeding 0.0% cations and below 30.0% cations,

[0185] P 5+ The content is 5.0% or more and 50.0% or less of cationic content.

[0186] Li + The content is ≥0.0% cations and ≤51.0% cations.

[0187] Na + The content is ≥0.0% cations and ≤44.0% cations.

[0188] K + The content is ≥0.0% cations and ≤45.0% cations.

[0189] Li + Na + K + and Cs +Total content R + It is 5.0% or more of cations.

[0190] Be 2+ Mg 2+ Ca 2+ 、Sr 2+ And Ba 2+ The total content is set as R. 2+ R 2+ Compared to Al 3+ With R 2+ The total content of cation ratio (R) 2+ / (Al 3+ +R 2+ The value is below 0.56.

[0191] In the glass composition expressed as anion %

[0192] O 2- The content is ≥10.0% anion and ≤95.0% anion.

[0193] F - The content is 10.0% or more and 90.0% or less of anions.

[0194] Furthermore, the external transmittance of this optical glass at wavelengths of 500nm to 1000nm, converted to a thickness of 10.0mm, is over 80%.

[0195] [2] According to the optical glass described in [1], wherein,

[0196] P 5+ Content relative to Al 3+ With P 5+ The total content of cation ratio (P) 5+ / (Al 3+ +P 5+ The value is above 0.30 and below 0.85.

[0197] [3] The optical glass according to [1] or [2], wherein,

[0198] Li + Content relative to R + With R 2+ The total cation ratio (Li + / (R + +R 2+ )) is above 0.00 and below 1.00.

[0199] [4] The optical glass according to any one of [1] to [3], wherein,

[0200] R +Compared to Al 3+ With P 5+ The total content of cation ratio (R) + / (Al 3+ +P 5+ The value is above 0.93.

[0201] [5] The optical glass according to any one of [1] to [4], wherein,

[0202] Li + With K + The total content relative to Al 3+ With P 5+ The total content of cation ratio ((Li + +K + ) / (Al 3+ +P 5+ The value is above 0.56.

[0203] [6] The optical glass according to any one of [1] to [5], wherein,

[0204] Li + with Na + The total content relative to Li + With K + The total content of cation ratio ((Li + +Na + ) / (Li + +K + The value is above 0.50 and below 1.59.

[0205] [7] The optical glass according to any one of [1] to [6] has a glass transition temperature Tg of 150°C or higher and 350°C or lower.

[0206] [8] The optical glass according to any one of [1] to [7] has an Abbe number νd of 70.00 or more and 82.00 or less.

[0207] [9] According to the optical glass described in [1], wherein,

[0208] P 5+ Content relative to Al 3+ With P 5+ The total content of cation ratio (P) 5+ / (Al 3+ +P 5+ The value is above 0.30 and below 0.85.

[0209] Li + Content relative to R + With R 2+ The total cation ratio (Li+ / (R + +R 2+ ()) is above 0.00 and below 1.00.

[0210] R + Compared to Al 3+ With P 5+ The total content of cation ratio (R) + / (Al 3+ +P 5+ The value is above 0.93.

[0211] Li + With K + The total content relative to Al 3+ With P 5+ The total content of cation ratio ((Li + +K + ) / (Al 3+ +P 5+ The value is above 0.56.

[0212] Li + with Na + The total content relative to Li + With K + The total content of cation ratio ((Li + +Na + ) / (Li + +K + The value is above 0.50 and below 1.59.

[0213] The glass transition temperature Tg of the aforementioned optical glass is above 150°C and below 350°C, and the Abbe number νd is above 70.00 and below 82.00.

[0214]

[10] An optical element comprising any one of [1] to [9] optical glass.

[0215] It should be understood that all the embodiments disclosed herein are exemplary and do not constitute a limitation. The scope of the invention is defined by the claims, not the foregoing description, and is intended to include all modifications within the meaning and scope of the claims.

[0216] For example, by adjusting the composition as described in the specification, an optical glass according to one aspect of the present invention can be obtained from the glass composition of the example above.

[0217] In addition, of course, any combination of two or more items exemplified in the specification or described as preferred items can be made.

Claims

1. An optical glass, wherein, in a glass composition expressed as cations%, S 6+ The content exceeds 0.0% cations but is below 30.0% cations. Al 3+ Content exceeding 10.0% cations but below 30.0% cations P 5+ The content is 5.0% or more and 50.0% or less of cations. Li + The content is ≥0.0% cations and ≤51.0% cations. Na + The content is ≥0.0% cations and ≤44.0% cations. K + The content is ≥0.0% cations and ≤45.0% cations. Li + Na + K + and Cs + Total content R + It is 5.0% or more of cations. Be 2+ Mg 2+ Ca 2+ 、Sr 2+ And Ba 2+ The total content is set as R. 2+ R 2+ Compared to Al 3+ With R 2+ The total content of cation ratio (R) 2+ / (Al 3+ +R 2+ The value is below 0.

56. In the glass composition expressed as anion % O 2- The content is above 10.0% and below 95.0% anion. F - The content is above 10.0% and below 90.0% anion. Furthermore, the external transmittance of the optical glass at wavelengths of 500nm to 1000nm, converted to a thickness of 10.0mm, is over 80%.

2. The optical glass according to claim 1, wherein, S 6+ The content is 0.5% or more, 1.0% or more, or 2.0% or more, and / or less than 29.0% cation, less than 25.0% cation, or less than 20.0% cation, and / or Al 3+ The content is 11.0% or more cations, and / or 28.0% or less cations, 26.0% or less cations, or 23.0% or less cations, and / or Li + The content is 1.0% or more, 7.0% or more, or 15.0% or more, and / or less than 51.0% cation, less than 48.0% cation, or less than 45.0% cation.

3. The optical glass according to claim 1 or 2, wherein, O 2- The content is 15.0% or more, 30.0% or more, 40.0% or more or 45.0% or more, and / or less than 88.5% or less, less than 86.0% or less, less than 83.5% or less, or less than 81.0% or less, and / or F - The content is 13.00% or more, 16.00% or more, 19.00% or more or 22.00% or more, and / or 85.0% or less, 70.0% or less, 60.0% or less or 54.0% or less.

4. The optical glass according to claim 1 or 2, wherein, P 5+ Content relative to Al 3+ With P 5+ The total content of cation ratio (P) 5+ / (Al 3+ +P 5+ )) is 0.30 or higher, 0.35 or higher, 0.40 or higher, or 0.50 or higher, and / or 0.85 or lower, 0.83 or lower, 0.81 or lower, 0.77 or lower, or 0.72 or lower, and / or Li + Na + K + and Cs + Total content R + The cation content is 10.0% or more, 20.0% or more, or 28.0% or more, and / or less than 65.0% cation, less than 63.0% cation, or less than 61.0% cation, and / or Li + Content relative to R + With R 2+ The total cation ratio (Li + / (R + +R 2+ )) is 0.00 or higher, 0.10 or higher, or 0.25 or higher, and / or 1.00 or lower, or 0.92 or lower, or 0.83 or lower, and / or R + Compared to Al 3+ With P 5+ The total content of cation ratio (R) + / (Al 3+ +P 5+ The values ​​are 0.93 or higher, 1.03 or higher, 1.13 or higher or 1.15 or higher, and / or 2.00 or lower, 1.94 or lower, 1.88 or lower or lower.

5. The optical glass according to claim 1 or 2, wherein, Li + With K + The total content relative to Al 3+ With P 5+ The total content of cation ratio ((Li + +K + ) / (Al 3+ +P 5+ )) is above 0.56, and / or Li + with Na + The total content relative to Li + With K + The total content of cation ratio ((Li + +Na + ) / (Li + +K + The values ​​are 0.50 or higher, 0.60 or higher, 0.70 or higher, or 0.87 or higher, and / or 1.59 or lower, 1.57 or lower, 1.55 or lower, or 1.35 or lower.

6. The optical glass according to claim 1 or 2, wherein, Be 2+ Mg 2+ Ca 2+ 、Sr 2+ And Ba 2+ The total content is set as R. 2+ R 2+ Compared to Al 3+ With R 2+ The total content of cation ratio (R) 2+ / (Al 3+ +R 2+ )) is greater than 0.00, greater than 0.02, and / or less than 0.56, less than 0.55, or less than 0.

50.

7. The optical glass according to claim 1 or 2, wherein the glass transition temperature Tg is above 150°C and below 350°C.

8. The optical glass according to claim 1 or 2, wherein the Abbe number νd is 70.00 or more, 71.00 or more, or 72.00 or more, and / or 82.00 or less.

9. The optical glass according to claim 1 or 2, wherein the refractive index nd is 1.420 or more, 1.430 or more, or 1.440 or more, and / or 1.510 or less, 1.500 or less, or 1.490 or less.

10. The optical glass according to claim 1, wherein, P 5+ Content relative to Al 3+ With P 5+ The total content of cation ratio (P) 5+ / (Al 3+ +P 5+ The value is above 0.30 and below 0.

85. Li + Content relative to R + With R 2+ The total cation ratio (Li + / (R + +R 2+ ()) is above 0.00 and below 1.

00. R + Compared to Al 3+ With P 5+ The total content of cation ratio (R) + / (Al 3+ +P 5+ The value is above 0.

93. Li + With K + The total content relative to Al 3+ With P 5+ The total content of cation ratio ((Li + +K + ) / (Al 3+ +P 5+ The value is above 0.

56. Li + with Na + The total content relative to Li + With K + The total content of cation ratio ((Li + +Na + ) / (Li + +K + The value is above 0.50 and below 1.

59. The optical glass has a glass transition temperature Tg of 150°C or higher and 350°C or lower, and an Abbe number νd of 70.00 or higher and 82.00 or lower.

11. An optical element comprising the optical glass according to any one of claims 1 to 10.

Images