Near-infrared absorbing glass and near-infrared cut-off filter

Abstract

The near-infrared absorbing glass provided by this invention maintains high transmittance in the visible light region (violet to red region) and excellent near-infrared cutoff capability even when thinned, while also suppressing weather resistance degradation. The near-infrared absorbing glass of this invention contains four or more major cations selected from the group consisting of: P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, and Y ions; wherein P ions, Li ions, and Cu ions are essential cations; the anion group contains at least O ions; the ratio of O ion content to P ion content (O ions / P ions) is 3.15 or less; and the O ion content in the glass composition, expressed as an anion percentage, is 90.0% or more (oxide basis). In the glass composition, based on Mohr's standard, the total content of oxides of the aforementioned major cations is 90.0% or more; the total content of MgO and Al2O3 (MgO+Al2O3) is 8.0% or less; the total ratio of Na2O, K2O, and ZnO content relative to Li2O content ((Na2O+K2O+ZnO) / Li2O) is 2.4 or less; the total content of B2O3 and SiO2 (B2O3+SiO2) is 3.0% or less; and the CuO content is α1% or more, where α1 is the value calculated by Equation 1 below, where R is the aforementioned ratio (O ions / P ions). (Equation 1) α1 = 70400 × exp(-2.855 × R)

Description

Technical Field

[0001] This invention relates to near-infrared absorbing glass and near-infrared cut-off filters. Prior Technology

[0002] In recent years, small cameras, such as those used in smartphones, have not only digitized the image information they acquire but also reconstructed the image through various computer processing methods. For example, it has become mainstream to capture a specific object and then adjust the color and contrast of the image. In this case, if color information that was not originally present is input into the camera sensor due to light reflection from the optical elements, this information must be excluded, so it is best to avoid it.

[0003] Near-infrared cut-off filters are designed to block near-infrared light (wavelength 700~1200nm) from reaching the sensor's sensitivity wavelength range. Generally, near-infrared cut-off filters are positioned directly in front of the sensor.

[0004] Near-infrared cut-off filters are widely used with near-infrared absorbing glass as the substrate and the glass is ground on a flat plate.

[0005] Near-infrared absorbing glasses generally contain Cu ions. An example of the spectral transmission characteristics of near-infrared absorbing glasses is shown in Figure 1. However, Figure 1 is not intended to limit the scope of this invention. The light absorption characteristics in the wavelength range of 700-1200 nm are manifested by Cu ions (Cu²⁺) in the glass. Glasses containing both Cu and P ions are particularly effective as near-infrared cutoff filters because they exhibit the near-infrared absorption characteristics of Cu ions (Cu²⁺) over a wide wavelength range (see, for example, Patent Document 1). [Preliminary Technology Documents] [Patent Literature]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2014-12630

[0007] In Figure 1, the transmittance curves for wavelengths beyond 600 nm show that the wavelength at which 50% transmittance is achieved is called the "half-value," which is one of the main specifications for near-infrared cutoff filters. The half-value varies depending on the filter specifications, but is mostly set within the wavelength range of 600 nm to 650 nm. A common method to achieve the desired half-value is to adjust either the thickness of the glass substrate or the concentration of Cu ions (Cu²⁺) in the glass, based on the Lambert-Beer law. Summary of the Invention

[0008] (The problem that the invention aims to solve)

[0009] Near-infrared cutoff filters require excellent near-infrared cutoff capability (i.e., having the required half-value and low near-infrared light transmittance) and high transmittance in the visible light domain (violet to red region).

[0010] Furthermore, the camera module used in smartphones and other devices in recent years has been required to balance miniaturization and high performance, and the thickness of the near-infrared cut-off filter has been reduced. Therefore, the thickness of the near-infrared absorbing glass has also changed from the conventional 1mm to around 0.45mm, 0.3mm, or 0.2mm in recent years, and ideally even as thin as around 0.1mm.

[0011] Simply thinning the near-infrared absorbing glass would reduce the required CuO optical concentration (moer number × thickness) for near-infrared absorption, leading to decreased near-infrared absorption efficiency. Increasing CuO has been considered to address this issue. However, simply increasing CuO would result in CuO absorption reaching the visible light region (i.e., the red region) around 600 nm, while transmittance at shorter wavelengths would also decrease. Therefore, it is quite difficult to simultaneously maintain transmittance in the visible light region (violet to red region) and near-infrared absorption.

[0012] Furthermore, for near-infrared absorbing glass, which is intended to provide near-infrared cutoff filters suitable for high-temperature and high-humidity environments, it is desirable to suppress the reduction of weather resistance under such conditions. However, according to the inventors' findings, it is not easy to simultaneously maintain transmittance in the visible light region (violet to red region) and near-infrared absorption while suppressing the reduction of weather resistance.

[0013] In view of the above, the near-infrared absorbing glass provided by one aspect of the present invention is a near-infrared absorbing glass that, even when thinned, still has high transmittance in the visible light region (violet region to red region), excellent near-infrared cutoff capability, and can suppress near-infrared absorbing glass with poor weather resistance; in addition, the present invention also provides a near-infrared cutoff filter made of the near-infrared absorbing glass. (Methods for solving problems)

[0014] The near-infrared absorbing glass (hereinafter also referred to as "glass 1") of the present invention contains four or more major cations selected from the group consisting of: P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions and Y ions; The essential cations contained in the P ion, Li ion, and Cu ion system; Anionic systems contain at least O ions; The ratio of O ion content to P ion content (O ion / P ion) is below 3.15; In the glass composition expressed as anion%, the O ion content is above 90.0% anion; In the glass composition based on oxides, Immers reference meter, The total content of oxides of the above-mentioned main cations is over 90.0%; The total content of MgO and Al2O3 (MgO + Al2O3) is below 8.0%; The ratio of Na₂O, K₂O, and ZnO contents to the total content ((Na₂O + K₂O + ZnO) / Li₂O) is less than 2.4. The total content of B2O3 and SiO2 (B2O3 + SiO2) is less than 3.0%; The CuO content is above α1%; α1 is derived from the following equation 1: (Equation 1) α1 = 70400 × exp(-2.855 × R) The calculated value; In equation 1 above, The above ratio (O ions / P ions) is used for the R series.

[0015] Furthermore, the near-infrared absorbing glass (hereinafter also referred to as "glass 2") of the present invention contains four or more major cations selected from the group consisting of: P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, and Y ions; The essential cations contained in the P ion, Li ion, and Cu ion system; Anionic systems contain at least O ions; The ratio of O ion content to P ion content (O ion / P ion) is below 3.15; In the glass composition expressed as anion%, the O ion content is above 90.0% anion; In the glass composition based on oxides, Immers reference meter, The total content of oxides of the above-mentioned main cations is over 90.0%; The total content of MgO and Al2O3 (MgO + Al2O3) is below 8.0%; The ratio of Na₂O, K₂O, and ZnO contents relative to Li₂O content ((Na₂O + K₂O + ZnO) / Li₂O) is less than 2.4. The total content of B2O3 and SiO2 (B2O3 + SiO2) is less than 3.0%; Satisfy the following equation 2: (Equation 2) C - 3200 × exp(-2.278 × R) ≧ 0 In equation 2 above, CuO content per mole volume of C-series glass (unit: millimoles / cc); The above ratio (O ions / P ions) is used for the R series.

[0016] Furthermore, the near-infrared absorbing glass (hereinafter also referred to as "glass 3") of the present invention contains four or more major cations selected from the group consisting of P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, Y ions, B ions and Si ions; The essential cations contained in the P ion, Li ion, and Cu ion system; Anionic systems contain at least O ions; The ratio of O ion content to P ion content (O ion / P ion) is below 3.15; In the glass composition expressed as anion%, the O ion content is above 90.0% anion; In the glass composition based on oxides, Immers reference meter, The total content of oxides of the above-mentioned main cations is over 90.0%; The total content of MgO and Al2O3 (MgO + Al2O3) is below 8.0%; The ratio of Na₂O, K₂O, and ZnO contents to the total content ((Na₂O + K₂O + ZnO) / Li₂O) is less than 2.4. From the following formula 3: (Equation 3) A1 = {O(P) - O(others)} × Cu The calculated A1 series is above 2500; In equation 3 above, O(P) represents the amount of oxygen constituting P-ion oxides in the glass composition based on oxides; O(others) refers to the oxygen content of the oxides constituting the main cations in the glass composition based on oxides, minus the oxygen content of O(P). Cu series indicates the molar-based CuO content in the glass composition based on oxides.

[0017] Furthermore, the near-infrared absorbing glass (hereinafter also referred to as "glass 4") of the present invention contains four or more major cations selected from the group consisting of P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, Y ions, B ions and Si ions; The essential cations contained in the P ion, Li ion, and Cu ion system; Anionic systems contain at least O ions; The ratio of O ion content to P ion content (O ion / P ion) is below 3.15; In the glass composition expressed as anion%, the O ion content is above 90.0% anion; In the glass composition based on oxides, Immers reference meter, The total content of oxides of the above-mentioned main cations is over 90.0%; The total content of MgO and Al2O3 (MgO + Al2O3) is below 8.0%; The ratio of Na₂O, K₂O, and ZnO contents to the total content ((Na₂O + K₂O + ZnO) / Li₂O) is less than 2.4. From the following formula 4: (Equation 4) A2 = {O(P) - O(others)} × C The calculated A2 series is above 700; In equation 4 above, CuO content per mole volume of C-series glass (unit: millimoles / cc); O(P) represents the amount of oxygen constituting P-ion oxides in the glass composition based on oxides; O(others) refers to the oxygen content of the oxide-based glass composition, minus the oxygen content of O(P) from the oxygen content of the oxides constituting the main cations mentioned above.

[0018] The near-infrared absorbing glass (hereinafter also referred to as "glass 5") of the present invention contains four or more major cations selected from the group consisting of: P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions and Y ions; The essential cations contained in the P ion, Li ion, and Cu ion system; Anionic systems contain at least O ions; The ratio of O ion content to P ion content (O ion / P ion) is below 3.15; In the glass composition expressed as anion%, the O ion content is above 90.0% anion; In the glass composition based on oxides, Immers reference meter, The total content of oxides of the above-mentioned main cations is over 90.0%; The total content of MgO and Al2O3 (MgO + Al2O3) is below 8.0%; The ratio of Na₂O, K₂O, and ZnO contents to the total content ((Na₂O + K₂O + ZnO) / Li₂O) is less than 2.4. The CuO content is above α2%; α2 is derived from the following equation 5: (Equation 5) α2 = (76522) × exp(-2.855 × R) The calculated value; In equation 5 above, The above ratio (O ions / P ions) is used for the R series.

[0019] Furthermore, the near-infrared absorbing glass (hereinafter also referred to as "glass 6") of the present invention contains four or more major cations selected from the group consisting of: P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, and Y ions; The essential cations contained in the P ion, Li ion, and Cu ion system; Anionic systems contain at least O ions; The ratio of O ion content to P ion content (O ion / P ion) is below 3.15; In the glass composition expressed as anion%, the O ion content is above 90.0% anion; In the glass composition based on oxides, Immers reference meter, The total content of oxides of the above-mentioned main cations is over 90.0%; The total content of MgO and Al2O3 (MgO + Al2O3) is below 8.0%; The ratio of Na₂O, K₂O, and ZnO contents to the total content ((Na₂O + K₂O + ZnO) / Li₂O) is less than 2.4. Satisfy the following equation 6: (Equation 6) C - (3478) × exp(-2.278 × R) ≧ 0 In equation 6 above, CuO content per mole volume of C-series glass (unit: millimoles / cc); The above ratio (O ions / P ions) is used for the R series. [Invention Effects]

[0020] According to one embodiment of the present invention, a near-infrared absorbing glass can be provided that, even when thinned, still exhibits high transmittance in the visible light range (violet to red region), excellent near-infrared cutoff capability, and the ability to suppress the reduction of weather resistance. Furthermore, according to one embodiment of the present invention, a near-infrared cutoff filter can be constructed from this near-infrared absorbing glass. Simple Explanation of the Diagram

[0021] Figure 1 shows an example of the spectral transmission characteristics of near-infrared absorbing glass. Implementation

[0022] Near-infrared absorbing glass Hereinafter, glass 1 to 6 will be collectively referred to as "glass" or "near-infrared absorbing glass". Unless otherwise stated, the descriptions of the composition and properties of the glass apply to glass 1 to 6.

[0023] In this invention and specification, the term "near-infrared absorbing glass" refers to glass that absorbs light in at least the entire near-infrared wavelength range (wavelength 700-1200 nm) or a portion thereof. Furthermore, the near-infrared absorbing glass of this invention, because its constituent ionic system contains O ions, can be classified as an oxide glass. "Oxide glass" refers to glass whose main network-forming component is an oxide. Also, the near-infrared absorbing glass of this invention, because its constituent ionic system contains both O ions (anions) and P ions (cations), can be classified as a phosphate glass. Additionally, O ions are anions of oxygen atoms and are generally also referred to as "oxide ions".

[0024] The following provides a more detailed explanation of glass 1 to 6.

[0025] <Glass Composition> (Analysis Methods) For the various components that make up glass, the content (mass percentage) of elements contained in the glass can be quantified using known methods (e.g., inductively coupled plasma atomic emission spectrometry (ICP-AES), inductively coupled plasma mass spectrometry (ICP-MS)). For anionic components, known analytical methods (such as ion chromatography, non-dispersive infrared absorption spectrometry (ND-IR)) can be used to identify and quantify the anionic components contained in glass. Furthermore, in this invention and this specification, the terms "0% content of constituent components, or no content or introduction" refer to the fact that the constituent component is not actually contained, and the constituent component is permissible to contain an unavoidable degree of impurities.

[0026] (Glass composition description based on oxides) Based on the results obtained from the above analysis, the content of each component in the oxide-based glass composition (unit: mole%) can be calculated. The specific method is as follows. By dividing the content of element i (element mass % Pi) obtained by the above analysis method by the atomic weight Mi of element i, the mole number ni = Pi / Mi of each element can be obtained. When the aforementioned element i is a cationic component Ai, the mole number ni of the obtained element is replaced with the mole number n'i of the corresponding oxide. Specifically, when the oxide composition formula of the cationic component Ai corresponding to element i is expressed as Ai xOy, it becomes n'i = ni / x. When the anionic component Bi is other than the O ion mentioned above, the corresponding mole number ni of the above element will be expressed as mi below. In the oxide-based glass composition, the content of the cation component Ai in oxides AixOy (PAi) (moles %) is determined by... PAi = n'i / (Σn'i + Σmi) × 100 The content of oxide reference glass in the composition can also be referred to as the "oxide reference fraction".

[0027] In the oxide-based glass composition, the oxide-based fraction PBi (moles%) of Bi, the anionic component other than O ions, is determined according to... PBi = mi / (Σn'i + Σmi ) × 100 express.

[0028] Here, Σn'i represents the total molar number of the oxides Ai xOy of the cationic components contained in the glass. However, depending on the significant figures of the content, there may be cases where even ignoring trace components will not affect the calculation results.

[0029] (anion%) The term "anion %" refers to the value calculated as "(content of the anion in moles %) / (total number of anions in the glass in moles %) × 100", which is the mole percentage of the total anion content relative to the anion content in moles. According to the above description of the composition of oxide reference glass, the percentage of O ions (anions) is... The oxide composition of the cation component Ai corresponding to element i is expressed as Ai xOy. The number of O atoms in the oxide of the cation component Ai is expressed using the oxide baseline fraction PAi (moles%) of the cation component Ai as Oi = PAi ×y. When the valence of the anion component Bk is set to Nk, it can be calculated by the following formula: (ΣOi -Σ(Nk / 2)Bk ) / (ΣOi -Σ(Nk / 2)Bk +ΣBk )×100 Here, ΣOi represents the total mole number of O ions in the oxide reference glass, and Σ(Nk / 2)Bk represents the mole number of O ions replaced by the anionic component Bk. The numerator (ΣOi - Σ(Nk / 2)Bk) represents the mole number of O ions contained in the glass. On the other hand, in this invention and this specification, when the oxygen content is analyzed using known methods and it is impossible to detect anionic components other than oxygen, all ions in the anionic components (i.e., 100% anion%) are considered as O ions.

[0030] (Catonic component) The valence of the relevant cation components is based on the formal valence of each cation. The so-called "formal valence" refers to the necessary valence for maintaining the electroneutrality of the oxide when the valence of the O ion constituting the oxide is set to -2, which can be explicitly obtained from the chemical formula of the oxide. For example, for Cu ions, to maintain the electroneutrality of O2- and Cu in the chemical formula of oxide CuO, the valence of Cu is +2. Similarly, for P ions, to maintain the electroneutrality of O2- and P in the chemical formula of oxide P2O5, the valence of P is +2 × 5 / 2 = +5. If this number is generalized, the formal valence of the cation Ai in oxide AixOy is "+2y / x". Therefore, when analyzing the composition of glass, it is not necessary to analyze the valence of the cations. Furthermore, the valence of the relevant anions (e.g., the valence of O ions is -2) is also based on the idea that O ions accept two electrons to form a closed shell structure. Therefore, when analyzing the composition of glass, it is not necessary to analyze the valence of anions. Also, a portion of Cu2+ will become Cu+ upon melting, but since this amount is usually extremely small, it is acceptable to consider the valence of Cu to be +2 for all of them.

[0031] (Anionic component) The aforementioned glass system contains at least O ions, and this content is 90.0% or more of anions in the glass composition expressed as anion percentage. Accordingly, the inventors believe that in a glass primarily composed of O ions, by reducing the O / P ratio, the absorption in the red region of CuO can be shifted towards longer wavelengths, thereby increasing the CuO content and improving near-infrared cutoff capability without reducing the red region transmittance. In the glass composition expressed as anion percentage, the O ion content is 90.0% or more, preferably 95.0% or more, more preferably 98.0% or more, and especially preferably 99.0% or more. A higher proportion of O ions in the anionic composition also suppresses volatilization during glass melting, which is preferable. Suppressing volatilization during glass melting is also preferable from the viewpoint of suppressing pore formation. In particular, from the viewpoint of suppressing volatilization during glass melting, improving productivity, and suppressing the generation of harmful gases during manufacturing, the O ion content is preferably 100%. Furthermore, the valence of the O ion is -2.

[0032] The aforementioned glass may contain only O ions in one anionic form, or it may contain O ions and one or more other anions in another anionic form. Examples of other anions include F ions, Cl ions, Br ions, and I ions. Furthermore, the valence of F ions, Cl ions, Br ions, and I ions is -1.

[0033] From the perspective of improving glass homogeneity and strength, the content of fluorine ions (F ions) in glass composition expressed as anion percentage is preferably 15.0% or less, more preferably 10.0% or less, exceptionally good 5.0% or less, very good 2.0% or less, and best 1.0% or less. In particular, from the viewpoint of suppressing volatilization during glass melting, improving productivity, and suppressing the generation of harmful gases during manufacturing, the aforementioned glass can also be F-free glass.

[0034] (O / P ratio) The mole ratio of cation content to anion content is the ratio (in moles%) of the components in question when the total amount of all cations and anions is set to 100 moles. Therefore, the ratio of O ion content to P ion content (O ion / P ion) is the ratio (in moles%) of O ion content to P ion content (in moles%) when the total amount of all cations and anions is set to 100 moles.

[0035] Method 1 for calculating the O / P ratio The relevant O / P ratio (also referred to as "R"), as described in the above description of the oxide reference glass composition, is... The oxide composition of the cation component Ai corresponding to element i is expressed as Ai xOy. The number of O atoms in the oxide of the cation component Ai is set as the oxide baseline fraction PAi (moles %) of the cation component Ai, which is Oi = PAi ×y. The valence of the anion component Bk is set as Nk. Equation D1:R1=ΣOi -Σ(Nk / 2)Bk Formula D2: R2 = Baseline fraction (moles) of P ion oxides (i.e., P2O5) × 2 The O / P ratio (R) can be obtained by the following formula. Equation D3: R = R1 / R2 For example, taking Comparative Example A as an example, the oxide reference glass composition of Comparative Example A, expressed in moles (%), is P₂O₅ = 53.59, Li₂O = 19.30, and CuO = 27.11. The number of O atoms in the molecular formula is P₂O₅: 5, Li₂O: 1, and CuO: 1. The mole number of O atoms in the molecular formula is P₂O₅: 267.95, Li₂O: 19.30, and CuO: 27.11. The O / P ratio of this glass can be obtained as follows. Determine the number of O ions (NS) in the glass molecular formula: 53.59P₂O₅ -19.30Li₂O-27.11CuO. "Glass molecular formula" refers to the glass composition expressed as a total of 100 molecules. That is, using the number of O ions contained in each oxide molecular formula MxOy (P2O5: 5, Li2O: 1, CuO: 1), it is determined by the following formula: NS =53.59×5+19.30×1+27.11×2=314.36 Calculate NS. In the glass system described above, the number of O ions replaced by other anions in the glass molecular formula is zero. Therefore, by dividing NS = 314.36 by the molar number of P contained in P2O5, 53.59 × 2, the O / P ratio can be obtained as 314.36 / (53.59 × 2) = 2.93…

[0036] Method 2 for calculating the O / P ratio When using known methods for analysis, in addition to detecting oxygen, one or more other anionic components are also detected, the oxygen content can be calculated using the following method (3): (1) the cation content based on the valence and elemental mole % of the cation components contained in the glass, and (2) the anion content based on the valence and elemental mole % of the anionic components other than oxygen. That is, the results of identification and quantitative analysis using known methods. (1) For the cationic components contained in the glass, calculate the total U of "the cationic content based on the number of oxygens y and the number of cations x of oxide MxOy, and the oxygen number y / x of each cation y / x × element mole %". (2) The anionic components other than oxygen are also determined by identification and quantitative analysis using known methods, and the anionic valence z, and the total V is calculated as "anionic content based on elemental moles % × number of oxygens replaced by each anionic z / 2". (3) UV can also be used as the O ion content relative to the P ion content.

[0037] The calculation examples for calculation method 2 can be illustrated by the following calculation example 1 and calculation example 2.

[0038] Example 1: When the elemental mole percentages of P ions, Li ions, and Cu ions are 22.0, 8.0, and 5.5 (expressed as elemental mole %), the y / x ratios of the corresponding oxides P₂O₅, Li₂O, and CuO are 2.5, 0.5, and 1.0, respectively. Therefore, the following calculation is obtained: U=22×2.5+8×0.5+5.5×1.0=64.5, The result was V=0. Therefore, the O ion mole percentage based on the element mole percentage is 64.5 (expressed as element mole %). From the ratio of the O ion value obtained in this way to the molar percentage of the analyzed P ions, the O / P ratio can be calculated as 64.5 / 22 = 2.93...

[0039] Example 2: The elemental mole percentages of P, Li, and Cu ions are quantified as 22.0, 8.0, and 5.5 (expressed as elemental mole %). When the elemental mole percentage of F ions is quantified as 4.0 (expressed as elemental mole %), the y / x of the corresponding oxides: P₂O₅, Li₂O, and CuO are 2.5, 0.5, and 1.0, respectively. Since the valence of F is -1, the result is... U=22×2.5+8×0.5+5.5×1.0=64.5, The result is V = 4 × 1 / 2 = 2. Therefore, the O ion mole percentage based on the element mole percentage is 62.5 (expressed as element mole %). From the ratio of the O ion value obtained in this way to the molar percentage of the analyzed P ions, the O / P ratio can be calculated as 62.5 / 22 = 2.84…

[0040] In glass 1 to 6, from the perspective of balancing the improvement of visible light transmittance, the improvement of near-infrared cutoff capability, and the improvement of glass thermal stability, the ratio of O ion content to P ion content (O / P ratio) is 3.15 or less. Among glass 1 to glass 6, the preferred O / P ratio is below 3.14, and the better ratios are below 3.13, below 3.12, below 3.11, below 3.10, below 3.09, below 3.08, below 3.07, below 3.06, below 3.05, below 3.04, below 3.03, below 3.02, below 3.01, and below 3.00. On the other hand, from the viewpoint of improving weather resistance and / or suppressing the decrease in solubility, a higher O / P ratio is preferred for glass 1 to glass 6. From this perspective, the preferred O / P ratio for glass 1 to glass 6 is 2.50 or higher, with the following order of preference: 2.60 or higher, 2.65 or higher, 2.70 or higher, 2.73 or higher, 2.75 or higher, 2.77 or higher, 2.80 or higher, 2.81 or higher, 2.82 or higher, 2.83 or higher, 2.84 or higher, 2.85 or higher, 2.86 or higher, 2.87 or higher, 2.88 or higher, 2.89 or higher, and 2.90 or higher.

[0041] (Catonic component) Glasses 1-6 contain at least four major cations selected from the group consisting of P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, and Y ions, and the P ions, Li ions, and Cu ions contained therein are essential cations. In the oxide reference glass composition (Mohr reference) of glasses 1-6, the total content of the oxides of the above major cations is more than 90.0%. In glasses 1-6, the total oxide content of the main cations is 90.0% or more, which helps to improve the thermal stability of the glass and / or helps to improve the optical homogeneity of the glass by suppressing pulsation and volatilization. From the above point of view, the total oxide content of the main cations in glasses 1-6 is preferably 92.0% or more, more preferably 93.0% or more, 95.1% or more, 96.1% or more, 97.1% or more, 98.1% or more, 98.6% or more, 99.1% or more, and 99.6% or more, or it can be set to 100%. In another embodiment, the total oxide content of the main cations in glasses 1-6 can be set to 100% or less, or 99.5% or less, 99% or less, 98.5% or less, 98.0% or less, and 97.5% or less.

[0042] The following section explains the content of cationic components in the oxide reference glass composition (Mohr reference).

[0043] CuO is an essential component for glass to have near-infrared cutoff capability, therefore the necessary cation system of glass 1 to 6 contains Cu ions.

[0044] In glass 1, the CuO content is α1% or higher. α1 is the value calculated using formula 1 below.

[0045] (Equation 1) α1 = 70400 × exp(-2.855 × R)

[0046] In Equation 1, the R-series O / P ratio.

[0047] Furthermore, the lower limit of CuO content in the relevant glass 2 is determined by the CuO content per mole volume of the glass, as specified by the following formula 2:

[0048] (Equation 2) C - 3200 × exp(-2.278 × R) ≧ 0

[0049] In Formula 2, CuO content per mole volume of C-series glass (unit: millimoles / cc) and O / P ratio of R-series glass are given.

[0050] In Equation 2, the above C series is obtained by the following method. The specific gravity D (g / cc) of the glass was determined using the C-series method. Based on the glass composition obtained from the aforementioned analysis, the mass equivalent to 1 mole of the glass composition (i.e., the molar molecular weight M (g / mole)) was calculated, and the molar volume M / D (unit: cc / mole) of the glass was obtained. From this, the following can be calculated: C = CuO mol% / (M / D) × 1000 (Unit: millimoles / cc) The above molar molecular weight M series Based on the above description of the oxide reference glass composition, when the formula weight of the oxide corresponding to the cation component Ai is set as MAi, the atomic weight of the anion component Bk is set as MBk, and the atomic weight of oxygen is set as Mo, the following formula can be obtained: M={Σ(PAi ×MAi )+Σ(PBk ×MBk )-Σ(Nk / 2)Mo} / ΣPAi For example, when the glass composition consists of s mol% A₂O (based on oxides), t mol% BO (based on oxides), and u mol% F (based on oxides), and s+t+u=100 (%), the formula weight of A₂O is MA (g / mol), the formula weight of BO is MB (g / mol), the atomic weight of F is MF (g / mol), and the atomic weight of oxygen is MO (g / mol), it becomes: M=(s×MA +t×MB +u×MF -u / 2×MO ) / (s+t) For example, the molar molecular weight M of Comparative Example A (the composition of the oxide reference glass, expressed in molar % as P₂O₅ = 53.59, Li₂O = 19.30, CuO = 27.11) described later is based on: P₂O₅ formula weight: 141.94 (g / molar) Li₂O formula weight: 29.88 (g / molar) CuO formula weight: 79.55 (g / molar) Then we can calculate M = (53.59 × 141.94 + 19.30 × 29.88 + 27.11 × 79.55) / (53.59 + 19.30 + 27.11) = 103.40 (g / molar).

[0051] Through in-depth research, the inventors have discovered that for anionic glass dominated by O ions, reducing the O / P ratio can suppress the decrease in transmittance in the red region by shifting the absorption of CuO in the red region towards the longer wavelength end, and can also increase the CuO content. Furthermore, the inventors have discovered a strong correlation between the O / P ratio and the CuO content that achieves a predetermined half-value with a given plate thickness. Therefore, for glass 1 with an O / P ratio within the aforementioned range, Formula 1 is used to define the lower limit of CuO content (α1, α2), while Formula 5 is used for glass 5. Additionally, for glass with an O / P ratio within the aforementioned range, Formula 2 is used to define the CuO content per mole volume, while Formula 6 is used for glass 6.

[0052] In glass 3, the CuO content is specified according to A1 calculated by the following formula 3, where A1 is 2500 or more.

[0053] (Equation 3) A1 = {O(P) - O(others)} × Cu

[0054] In Formula 3, O(P) represents the oxygen content of the oxide constituting P-ion oxide in the oxide-based glass composition, and O(others) represents the oxygen content of the oxide constituting the aforementioned main cations of glass 3 after deducting the above-mentioned O(P) from the oxygen content of the oxide constituting the oxide. Cu represents the CuO content in the oxide-based glass composition in molar terms.

[0055] The “O(P)” in Equation 3 is calculated as follows. When the P2O5 content in the oxide reference glass composition (mole reference) is M moles%, the number of oxygen atoms in the P2O5 chemical formula is 5, and O(P) is calculated according to "O(P) = M × 5". Similarly, the main cations other than P ions are also calculated by using the oxide content value in the oxide reference glass composition (Mohr reference) and the number of oxygen atoms contained in the oxides formed by each cation according to its formal valence state, to determine the oxygen content of each cation oxide. The total amount of oxygen calculated for the main cationic oxides, minus O(P), is the value of "O(others)". When the CuO content in the oxide reference glass composition (Mohr reference) is N Mohr%, "A" is calculated as A1 = {O(P) - O(others)} × N.

[0056] As described above, the inventors have newly discovered that for anionic glass dominated by O ions, reducing the O / P ratio can suppress the decrease in transmittance in the red region by shifting the absorption of CuO in the red region towards the longer wavelength end, and can also increase the CuO content. Furthermore, by using chemical species other than PO coordinated on CuO, which are composed of chemical species with smaller ionic radii and lower valence numbers, the newly discovered results 1) and 2) below can improve the transmittance in the visible light region (violet to red region). Regarding glass 3, according to this discovery, the CuO content is specified based on A calculated by Equation 3. 1) By making the absorption from Cu2+ longer wavelengths, the transmittance in the red region can be increased. 2) By allowing the glass to form a liquid phase at low temperatures, the generation of Cu+, which would lead to absorption in the purple region around 400nm, can also be suppressed.

[0057] Regarding glass 3, from the perspective of balancing improved visible light transmittance and improved near-infrared cutoff capability, A1 The minimum score is 2500 or above, the better score is 2800 or above, and the even better score is 2900 or above, 3000 or above, 3100 or above, 3200 or above, 3300 or above, 3400 or above, 3500 or above, 3600 or above, 3700 or above, 3800 or above, 3900 or above, 4000 or above, 4100 or above, 4200 or above, 4300 or above, 4400 or above, 4500 or above, 4600 or above, 4700 or above, 4800 or above, 4900 or above, 5000 or above, 5100 or above, 5200 or above, 5300 or above, 5400 or above, 5500 or above, 5600 or above, 5700 or above, 5800 or above, 5900 or above, 6000 or above, 6100 or above, 6200 or above, 6300 or above, 6400 or above, and 6500 or above. On the other hand, considering the reduced thermal stability of glass due to the high content of Cu and O, the reduced transmittance at the required half-value wavelength, and / or the need to further suppress the reduction in thermal stability or weather resistance caused by insufficient O (others), A is preferably below 20,000, with the preferred order being below 19,000, below 18,000, below 17,000, below 16,000, below 150,000, below 14,000, below 13,000, below 12,000, below 11,000, below 10,000, below 9,000, and below 8,000. Furthermore, to achieve the required half-value with a thinner plate thickness, a higher value is generally preferred.

[0058] In glass 4, the CuO content is calculated according to the following formula 4, A2 is specified, and A2 is 700 or above.

[0059] (Equation 4) A2 = {O(P) - O(others)} × C

[0060] In Formula 4, the CuO content per mole volume of C-series glass (unit: millimoles / cc). O(P) represents the oxygen content of P-ion oxides in the glass composition based on oxides; O(others) represents the oxygen content of the aforementioned O(P) minus the oxygen content of the oxides constituting the aforementioned main cations in the glass composition based on oxides.

[0061] Regarding glass 4, from the perspective of balancing improved visible light transmittance and improved near-infrared cutoff capability, A2 is 700 or higher, preferably 800 or higher, and even better in the following order: 850 or higher, 890 or higher, 1000 or higher, 1100 or higher, 1200 or higher, 1300 or higher, 1400 or higher, 1500 or higher, 1600 or higher, 1700 or higher, and 1800 or higher. On the other hand, from the perspective of reducing the thermal stability of the glass due to the large content of Cu and O, reducing the transmittance at the required half-value wavelength, and / or further suppressing the reduction in thermal stability or weather resistance of the glass due to insufficient O (others), A2 is preferably 5000 or lower, and even better in the following order: 4000 or lower, 3500 or lower, 3000 or lower, 2500 or lower, and 2000 or lower. In addition, in order to achieve the required transmittance half-value with a thinner plate thickness, there is a tendency for a higher value to be better.

[0062] Furthermore, in glass 5, the CuO content is above α2%. α2 is a value calculated using the following formula 5.

[0063] (Equation 5) α² = 76522 × exp(-2.855 × R)

[0064] In Equation 5, the R-series O / P ratio.

[0065] Furthermore, for glass 6, the lower limit of CuO content is determined by the CuO content per mole volume of the glass, as specified by the following formula 6.

[0066] (Equation 6) C - 3478 × exp(-2.278 × R) ≧ 0

[0067] In Formula 6, CuO content per mole volume of C-series glass (unit: millimoles / cc) and O / P ratio of R-series glass are given.

[0068] The CuO content of glasses 1 to 6 in the oxide reference glass composition (Mohr reference) is preferably 4.0% or more, with the preferred order being 5.0% or more, 6.0% or more, 7.0% or more, 7.5% or more, 8.0% or more, 8.5% or more, 9.0% or more, 9.5% or more, 10.0% or more, 10.5% or more, 11.0% or more, 11.5% or more, 12.0% or more, 12.5% ​​or more, 13.0% or more, 13.5% or more, 14.0% or more, 14.5% or more, 15.0% or more, 15.5% or more, 16.0% or more, 16.5% or more, 17.0% or more, 17.5% or more, 18.0% or more, 18.5% or more, 19.0% or more, 19.5% or more, and 20.0% or more. From the perspective of introducing residual glass-forming components into the space and maintaining the thermal stability of the glass, the CuO content is preferably below 48.0%, with the following preferred order: below 47.0%, below 46.0%, below 45.0%, below 44.0%, below 43.5%, below 43.0%, below 42.5%, below 42.0%, below 41.5%, below 41.0%, below 40.5%, below 40.0%, below 39.5%, below 39.0%, below 38.5%, below 38.0%, below 37.5%, below 37.0%, below 36.5%, below 36.0%, below 35.5%, below 35.0%, below 34.5%, below 34.0%, below 33.5%, below 33.0%, below 32.5%, below 32.0%, below 31.5%, and below 31.0%.

[0069] For transmittance characteristics with a thickness of 0.11 mm, in order to achieve an external transmittance of 50% including reflection loss at a wavelength λT 50 in the range of 600 nm to 650 nm, the CuO content in the oxide reference glass composition (Mohr reference) is preferably 15.0% or more, with the preferred order being 15.5% or more, 16.0% or more, 16.5% or more, 17.0% or more, 17.5% or more, 18.0% or more, 18.5% or more, 19.0% or more, 19.5% or more, and 20.0% or more. For transmittance characteristics with a thickness of 0.21 mm, in order to achieve an external transmittance of 50% including reflection loss at a wavelength λT 50 in the range of 600 nm to 650 nm, the CuO content in the oxide reference glass composition (Mohr reference) is preferably 10.0% or more, with the preferred order being 10.5% or more, 11.0% or more, 11.5% or more, 12.0% or more, 12.5% ​​or more, 13.0% or more, 13.5% or more, 14.0% or more, 14.5% or more, 15.0% or more, 15.5% or more, 16.0% or more, 16.5% or more, 17.0% or more, 17.5% or more, 18.0% or more, 18.5% or more, 19.0% or more, 19.5% or more, and 20.0% or more. For transmittance characteristics with a thickness of 0.25 mm, in order to achieve an external transmittance of 50% including reflection loss at a wavelength λT 50 in the range of 600 nm to 650 nm, the CuO content in the oxide reference glass composition (Mohr reference) is preferably 10.0% or more, with the preferred order being 10.5% or more, 11.0% or more, 11.5% or more, 12.0% or more, 12.5% ​​or more, 13.0% or more, 13.5% or more, 14.0% or more, 14.5% or more, 15.0% or more, 15.5% or more, 16.0% or more, 16.5% or more, 17.0% or more, 17.5% or more, 18.0% or more, 18.5% or more, 19.0% or more, 19.5% or more, and 20.0% or more. On the other hand, considering the transmittance characteristics of a thickness of 0.25mm, if the CuO content increases significantly, the wavelength λT50, which includes reflection loss, may be lower than 600nm if the external transmittance reaches 50%. Therefore, the preferred CuO content is below 35.0%, with the following order of preference: below 34.0%, below 33.0%, below 32.0%, below 31.0%, below 30.0%, below 29.5%, below 29.0%, below 28.5%, below 28.0%, below 27.5%, below 27.0%, below 26.5%, below 26.0%, below 25.5%, below 25.0%, below 24.5%, below 24.0%, below 23.5%, below 23.0%, below 22.5%, below 22.0%, below 21.5%, below 21.0%, below 20.5%, and below 20.0%. To achieve an external transmittance (including reflection loss) of 50% at wavelengths above 550 nm, the glass thickness is less than 0.25 mm at a wavelength of 645 nm. The CuO content in the oxide-based glass composition (Mohr-based) is preferably 10.0% or higher, with the preferred order being 10.5% or higher, 11.0% or higher, 11.5% or higher, 12.0% or higher, 12.5% ​​or higher, 13.0% or higher, 13.5% or higher, 14.0% or higher, 14.5% or higher, 15.0% or higher, 15.5% or higher, 16.0% or higher, 16.5% or higher, 17.0% or higher, 17.5% or higher, 18.0% or higher, 18.5% or higher, 19.0% or higher, 19.5% or higher, and 20.0% or higher. To achieve an external transmittance (including reflection loss) of 50% at wavelengths above 550 nm, the glass thickness is 0.25 mm or less at a wavelength of 633 nm. The CuO content in the oxide-based glass composition (Mohr-based) is preferably 10.5% or more, with the preferred order being 11.0% or more, 11.5% or more, 12.0% or more, 12.5% ​​or more, 13.0% or more, 13.5% or more, 14.0% or more, 14.5% or more, 15.0% or more, 15.5% or more, 16.0% or more, 16.5% or more, 17.0% or more, 17.5% or more, 18.0% or more, 18.5% or more, 19.0% or more, 19.5% or more, and 20.0% or more.

[0070] For both glass 2 and glass 4, a C value of 3.0 or higher is preferred, with the following order of preference: 3.1 or higher, 3.3 or higher, 3.5 or higher, 3.7 or higher, 3.9 or higher, 4.0 or higher, 4.1 or higher, 4.2 or higher, 4.3 or higher, 4.4 or higher, 4.5 or higher, 4.6 or higher, 4.7 or higher, 4.8 or higher, 4.9 or higher, 5.0 or higher, 5.1 or higher, 5.2 or higher, 5.3 or higher, 5.4 or higher, and 5.5 or higher. From the perspective of introducing residual glass-forming components into the space and maintaining the thermal stability of the glass, the C-value is preferably below 16.0, with the following preferred order: below 15.0, below 14.0, below 13.5, below 13.0, below 12.5, below 12.0, below 11.9, below 11.8, below 11.7, below 11.6, below 11.5, below 11.4, below 11.3, below 11.2, below 11.1, below 11.0, and below 1... Below 0.9, below 10.8, below 10.7, below 10.6, below 10.5, below 10.4, below 10.3, below 10.2, below 10.1, below 10.0, below 9.9, below 9.8, below 9.7, below 9.6, below 9.5, below 9.4, below 9.3, below 9.2, below 9.1, below 9.0, below 8.9, below 8.8, below 8.7, below 8.6, below 8.5.

[0071] In glass types 1 to 6, the CuO content can be set to α3% or higher. α3 is a value calculated using the following formula 7.

[0072] (Equation 7) α3 =(70400×0.25 / d)×exp(-2.855×R)

[0073] In Equation 7, R represents the O / P ratio. The d-coefficient can take values ​​greater than 0 but less than 0.25. For example, d-coefficients can be set to 0.25, 0.24, 0.23, 0.22, 0.21, 0.20, 0.19, 0.18, 0.17, 0.16, 0.15, 0.14, 0.13, 0.12, 0.11, 0.10, 0.09, 0.08, 0.07, 0.06, 0.05, 0.04, 0.03, 0.02, 0.01, etc. However, the d-value is not limited to these values. To achieve the desired transmittance half-value using a thinner plate thickness, a smaller d-value tends to be better.

[0074] For example, when d=0.11, the CuO content can be set to α3% or more, and α3 is calculated by the following formula. α3 =(70400×0.25 / 0.11)×exp(-2.855×R)

[0075] In glass, if the thickness of the glass plate is set as D (mm) when the external transmittance of light with a wavelength of 633nm is 50%, then in Equation 7 above, it can be set as d=D. In this case, α3 is calculated by the following formula. α3 =(70400×0.25 / D)×exp(-2.855×R)

[0076] For glasses 1 to 6, the lower limit of CuO content can also be set as the value specified by formula 8, using the CuO content per mole volume of the glass.

[0077] (Equation 8) C-3200×0.25 / d×exp(-2.855×R)≧0

[0078] In Equation 8, the d-coefficient can take values ​​greater than 0 but less than 0.25. For example, the d-coefficient can be set to 0.25, 0.24, 0.23, 0.22, 0.21, 0.20, 0.19, 0.18, 0.17, 0.16, 0.15, 0.14, 0.13, 0.12, 0.11, 0.10, 0.09, 0.08, 0.07, 0.06, 0.05, 0.04, 0.03, 0.02, 0.01, etc. However, the d-value is not limited to these values. To achieve the desired transmittance half-value using a thinner plate thickness, a smaller d-value tends to be better.

[0079] For example, when d=0.11, Equation 8 becomes the following: C-3300×0.25 / 0.11×exp(-2.855×R)≧0

[0080] In glass, if the thickness of the glass plate is set as D (mm) when the external transmittance of light with a wavelength of 633nm is 50%, then in Equation 8 above, it can be set as d=D. In this case, Equation 8 becomes the following equation.

[0081] The relevant CuO content of glass 1 to 6 can also meet the requirements of one or more formulas for other relevant glasses.

[0082] Glasses in series 1-6 contain phosphorus (P) ions as an essential cation. As mentioned earlier, from the perspective of balancing improved visible light transmittance and near-infrared cutoff capability, a lower O / P ratio is preferable. To reduce the O / P ratio, increasing the P₂O₅ content is preferable. In this regard, the P2O5 content in the oxide reference glass composition (Mohr reference) is preferably 33.0% or higher, and more preferably 34.0% or higher, 35.0% or higher, 36.0% or higher, 37.0% or higher, 38.0% or higher, 39.0% or higher, 40.0% or higher, 40.5% or higher, 41.0% or higher, 41.5% or higher, 42.0% or higher, 42.5% or higher, 43.0% or higher, 43.5% or higher, 44.0% or higher, 44.5% or higher, 45.0% or higher, 45.5% or higher, 46.0% or higher, 46.5% or higher, 47.0% or higher, 47.5% or higher, 48.0% or higher, 48.5% or higher, 49.0% or higher, 49.5% or higher, and 50.0% or higher. Since P2O5 itself is a component that does not have near-infrared absorption capability, from the perspective of increasing the content of CuO with near-infrared absorption capability, the P2O5 content is preferably below 72.0%, with the following preferred order: below 71.0%, below 70.0%, below 69.5%, below 69.0%, below 68.5%, below 68.0%, below 67.5%, below 67.0%, below 66.5%, below 66.0%, below 65.5%, below 65.0%, below 64.5%, below 64.0%, below 63.5%, below 63.0%, below 62.5%, below 62.0%, below 61.5%, below 61.0%, below 60.5%, and below 60.0%. Furthermore, from the perspective of further suppressing the reduction in weather resistance and / or suppressing the reduction in solubility, a P2O5 content below the above values ​​is preferable.

[0083] To achieve the desired transmittance characteristics, the aforementioned glass preferably consists primarily of oxide reference glass composed of P₂O₅, Li₂O, and CuO. In this regard, the total content of P₂O₅, Li₂O, and CuO (P₂O₅ + Li₂O + CuO) is preferably 50.0% or more, with a more preferred order of 55.0% or more, 60.0% or more, 65.0% or more, 70.0% or more, 75.0% or more, 80.0% or more, 83.0% or more, 86.0% or more, 88.0% or more, and 90.0% or more. The aforementioned glass system must contain P ions, Li ions, and Cu ions as essential cations. To obtain the glass's thermal stability and / or chemical durability, it further contains one or more cations selected from the main cation group. Therefore, the total content (P2O5 + Li2O + CuO) is less than 100%, preferably below 9.9%, and the better order is below 99.8%, below 99.7%, below 99.6%, below 99.5%, below 99.4%, below 99.2%, below 99.0%, below 98.0%, below 97.0%, below 96.0%, below 95.0%, below 94.0%, below 93.0%, below 92.0%, below 91.0%, below 90.0%, below 89.0%, below 88.0%, below 87.0%, below 86.0%, and below 85.0%.

[0084] In terms of transmittance characteristics with a thickness of 0.11 mm, for the wavelength λT 50, which includes reflection loss, to achieve an external transmittance of 50% in the range of 600 nm to 650 nm, the total content of P2O5, Li2O and CuO (P2O5 + Li2O + CuO) in the oxide reference glass composition (Mohr reference) is preferably 84.0% or more, and more preferably 85.0% or more, 86.0% or more, 87.0% or more, 88.0% or more, 89.0% or more, and 90.0% or more. For transmittance characteristics with a thickness of 0.21 mm, in order to achieve an external transmittance of 50% including reflection loss at a wavelength λT 50 in the range of 600 nm to 650 nm, the total content of P2O5, Li2O and CuO (P2O5 + Li2O + CuO) in the oxide reference glass composition (Mohr reference) is preferably 80.0% or more, and more preferably 81.0% or more, 82.0% or more, 83.0% or more, 84.0% or more, 85.0% or more, 86.0% or more, 87.0% or more, 88.0% or more, 89.0% or more, and 90.0% or more. For transmittance characteristics with a thickness of 0.25 mm, in order to achieve an external transmittance of 50% including reflection loss at a wavelength λT 50 in the range of 600 nm to 650 nm, the total content of P2O5, Li2O and CuO (P2O5 + Li2O + CuO) in the oxide reference glass composition (Mohr reference) is preferably 75.0% or more, and more preferably 76.0% or more, 77.0% or more, 78.0% or more, 79.0% or more, 80.0% or more, 81.0% or more, 82.0% or more, 83.0% or more, 84.0% or more, 85.0% or more, 86.0% or more, 87.0% or more, 88.0% or more, 89.0% or more, and 90.0% or more. For a wavelength of 550 nm or higher, and for an external transmittance of 50% including reflection loss at a wavelength λT 50 of 645 nm, the glass thickness is less than 0.25 mm. The total content of P2O5, Li2O, and CuO (P2O5 + Li2O + CuO) in the oxide-based glass composition (Mohr's standard) is preferably 80.0% or higher, and more preferably 81.0% or higher, 82.0% or higher, 83.0% or higher, 84.0% or higher, 85.0% or higher, 86.0% or higher, 87.0% or higher, 88.0% or higher, 89.0% or higher, and 90.0% or higher. To achieve an external transmittance (including reflection loss) of 50% at wavelengths above 550 nm, the glass thickness is 0.25 mm or less at a wavelength of 633 nm. The total content of P2O5, Li2O, and CuO (P2O5 + Li2O + CuO) in the oxide-based glass composition (Mohr's standard) is preferably 81.0% or more, with the preferred order being 82.0% or more, 83.0% or more, 84.0% or more, 85.0% or more, 86.0% or more, 87.0% or more, 88.0% or more, 89.0% or more, and 90.0% or more. Examples of glass systems conforming to the above-described form include the glass of Examples 1 to 60 described below.

[0085] On the other hand, as another form, for glass with a total content of MgO, CaO, SrO, BaO, and ZnO (MgO+CaO+SrO+BaO+ZnO) relative to the total content of Li₂O, Na₂O, and K₂O (Li₂O+Na₂O+K₂O) (Li₂O+Na₂O+K₂O) of 2.0 or higher, considering the transmittance characteristics of a thickness of 0.11 mm, in order to achieve an external transmittance of 50% including reflection loss at a wavelength λT₅ in the range of 600nm~650nm, the total content of P₂O₅, Li₂O, and CuO (P₂O₅ + Li₂O) of 50% (MgO+CaO+SrO+BaO+ZnO) of 50% (Li₂O+Na₂O+K₂O) of 50%, the total content of P₂O₅, Li₂O, and CuO (P₂O₅ + Li₂O) of 50% (MgO+CaO+SrO+BaO+ZnO) of 50% (Li₂O+Na₂O+K₂O) of 50% (Li₂O+Na₂O+K₂O) of 50% (MgO+CaO+SrO+BaO+Zn ... In the oxide reference glass composition (Mohr reference), the content of O+CuO is preferably 65.0% or more, and the preferred order is 66.0% or more, 67.0% or more, 68.0% or more, 69.0% or more, and 70.0% or more. Regarding the other aspect mentioned above, for the transmittance characteristics of a thickness of 0.21 mm, in order to make the external transmittance, including reflection loss, 50% within the wavelength λT 50 range of 600 nm to 650 nm, the total content of P2O5, Li2O and CuO (P2O5 + Li2O + CuO) in the oxide reference glass composition (Mohr reference) is preferably 60.0% or more, and more preferably 61.0% or more, 62.0% or more, 63.0% or more, 64.0% or more, and 65.0% or more, respectively. Regarding the other aspect mentioned above, in terms of transmittance characteristics with a thickness of 0.25 mm, for the wavelength λT 50, which includes reflection loss, to achieve an external transmittance of 50% in the range of 600 nm to 650 nm, the total content of P2O5, Li2O, and CuO (P2O5 + Li2O + CuO) in the oxide reference glass composition (Mohr reference) is preferably 55.0% or more, and more preferably 56.0% or more, 57.0% or more, 58.0% or more, 59.0% or more, and 60.0% or more, respectively. In relation to the other aspect mentioned above, for a wavelength λT 50 at which the external transmittance, including reflection loss, is 50% at wavelengths above 550 nm and the glass thickness is below 0.25 mm, the total content of P2O5, Li2O, and CuO (P2O5 + Li2O + CuO) in the oxide-based glass composition (Mohr's standard) is preferably above 60.0%, and more preferably above 61.0%, above 62.0%, above 63.0%, above 64.0%, and above 65.0%. In another related form, for a glass thickness of 0.25 mm or less with an external transmittance of 50% including reflection loss at wavelengths above 550 nm, the total content of P2O5, Li2O and CuO (P2O5 + Li2O + CuO) in the oxide-based glass composition (Mohr's standard) is preferably 61.0% or more, more preferably 62.0% or more, 63.0% or more, 64.0% or more, 65.0% or more, or 66.0% or more. Examples of glass systems conforming to the other form described above include embodiments 61-66 described later.

[0086] Glasses 3 and 4 contain B ions and Si ions in the aforementioned main cation group. On the other hand, glasses 1, 2, 5, and 6 do not contain B ions or Si ions, which easily increase the dissolution temperature, in the aforementioned main cation group. From the viewpoint of improving the near-infrared cutoff capability and enhancing the visible light transmittance, glasses 1 to 6 can be configured as glasses containing one or both of B ions and Si ions, which tend to shift the half-value towards the shorter wavelength end. Alternatively, glasses can be configured as glasses that do not contain either B ions or Si ions.

[0087] In the oxide-based glass composition (Mohr standard), from the viewpoint of improving visible light transmittance, the total content of B2O3 and SiO2 (B2O3 + SiO2) of the relevant glass 1 and glass 2 is 3.0% or less, preferably 2.5% or less, and more preferably 2.0% or less, 1.5% or less, 1.0% or less, and 0.5% or less, respectively.

[0088] For the relevant glasses 3 to 6, in the oxide reference glass composition (Mohr reference), from the viewpoint of further improving the transmittance in the visible light range, the total content of B2O3 and SiO2 (B2O3 + SiO2) is preferably 3.0% or less, and the preferred order is 2.5% or less, 2.0% or less, 1.5% or less, 1.0% or less, and 0.5% or less.

[0089] In glass 1 to 6, the total content of B2O3 and SiO2 (B2O3 + SiO2) can be set to 0%, more than 0%, or more than 0%.

[0090] In glass types 1 to 6, from the perspective of further improving visible light transmittance, the B2O3 content is preferably below 3.0%, with the preferred order being below 2.5%, below 2.0%, below 1.5%, below 1.0%, and below 0.5%. The B2O3 content can also be set to 0%. On the other hand, for the relevant glasses 1 to 6, when the rough melting of the glass is carried out using a quartz crucible to promote glass homogenization, the SiO2 content is preferably greater than 0%, and more preferably in the following order: 0.01% or more, 0.02% or more, 0.03% or more, 0.04% or more, 0.05% or more, 0.1% or more, 0.2% or more, and 0.3% or more. However, excessive SiO2 introduced into the glass tends to reduce the optical homogeneity of the glass. In this regard, for glasses 1 to 6, the SiO2 content is preferably less than 2.0%, and more preferably in the following order: less than 1.4%, less than 0.9%, less than 0.8%, less than 0.6%, and less than 0.4%.

[0091] Glasses in series 1-6 contain Li ions as an essential cation. Compared to other glass compositions, Li₂O better enhances the ability of CuO to maintain absorption in the long wavelength range and has less adverse impact on weather resistance. From this perspective, the preferred Li₂O content is 0.1% or higher, with the following preferred values ​​in order: 0.5% or higher, 1.0% or higher, 1.5% or higher, 2.0% or higher, 2.5% or higher, 3.0% or higher, 3.5% or higher, 4.0% or higher, 4.5% or higher, 5.0% or higher, 5.5% or higher, 6.0% or higher, 6.5% or higher, 7.0% or higher, 7.5% or higher, and 8.0% or higher. On the other hand, from the viewpoint of ensuring the thermal stability of glass and / or maintaining greater resistance to weathering, the preferred Li₂O content is 35.0% or less, with the following preferred order: 34.0% or less, 33.0% or less, 32.0% or less, 31.0% or less, 30.0% or less, 29.5% or less, 29.0% or less, 28.5% or less, 28.0% or less, 27.5% or less, 27.0% or less, 26.5% or less, 26.0% or less, 25.5% or less, 25.0% or less, 24.5% or less, 24.0% or less, 23.5% or less, 23.0% or less, 22.5% or less, 22.0% or less, 21.5% or less, 21.0% or less, 20.5% or less, and 20.0% or less.

[0092] From the perspective of improving solubility and visible light transmittance, the total content of MgO and Al2O3 (MgO + Al2O3) in glass 1 to 6 is preferably below 8.0% and below 7.5%, respectively. The more preferred order is below 7.0%, below 6.5%, below 6.0%, below 5.5%, below 5.0%, below 4.5%, below 4.0%, below 3.5%, below 3.0%, below 2.5%, below 2.0%, below 1.8%, below 1.6%, below 1.5%, and below 1.4%. It can also be set to 0%. On the other hand, the total content of MgO and Al2O3 (MgO+Al2O3) can be set to more than 0% from the viewpoint of improving the weather resistance and mechanical strength of glass, preferably more than 0.1%, and even more in the following order: more than 0.2%, more than 0.3%, more than 0.4%, more than 0.5%, more than 0.6%, more than 0.7%, more than 0.8%, more than 0.9%, more than 1.0%, more than 1.1%, and more than 1.3%.

[0093] Al₂O₃ is a component that helps improve weather resistance. The Al₂O₃ content can be set to 0%, 0% or more, or greater than 0%. From the viewpoint of improving weather resistance, it is preferably 0.1% or more, with the preferred order being 0.2% or more, 0.3% or more, 0.4% or more, 0.5% or more, 0.6% or more, 0.7% or more, 0.9% or more, 1.1% or more, 1.3% or more, and 1.5% or more. On the other hand, from the viewpoint of further suppressing the reduction of visible light transmittance, the Al₂O₃ content is preferably 8.0% or less, with the preferred order being 7.5% or less, 7.0% or less, 6.0% or less, 5.5% or less, 5.0% or less, 4.5% or less, 4.0% or less, 3.5% or less, 3.0% or less, and 2.5% or less. From the perspective that improving near-infrared absorption characteristics is more important than maintaining the weather resistance of glass, and that suppressing the shift of CuO absorption towards shorter wavelengths can further improve the transmittance in the visible light domain and improve near-infrared absorption characteristics, the preferred Al2O3 content is less than 2.0%, and the better order is below 1.9%, below 1.8%, below 1.7%, below 1.6%, below 1.5%, below 1.4%, below 1.3%, below 1.2%, below 1.1%, below 1.0%, below 0.9%, below 0.8%, below 0.7%, below 0.6%, and below 0.5%.

[0094] MgO can be added appropriately to adjust the thermal stability of glass, but because it shifts CuO absorption towards shorter wavelengths, it tends to be more difficult to increase the CuO content. Furthermore, as the MgO content increases, the glass's solubility tends to decrease. From this perspective, the MgO content is preferably 9.0% or less, and more preferably 8.0%, 7.0%, 6.0%, 5.0%, 4.0%, 3.0%, and 2.0% or less. The MgO content can also be set to 0%. Alternatively, from the viewpoint of improving the mechanical strength of glass, the MgO content can be set to more than 0%, preferably more than 0.5%, and more preferably more than 1.0%.

[0095] La₂O₃ is a component that helps improve weather resistance without impairing the near-infrared absorption characteristics of glass. The preferred La₂O₃ content is 0.10% or more, with the more preferred values ​​being 0.15% or more, 0.18% or more, and 0.21% or more. On the other hand, from the viewpoint of further suppressing the reduction in visible light transmittance, the preferred La₂O₃ content is 8.0% or less, with the more preferred values ​​being 7.0% or less, 6.5% or less, 6.0% or less, 5.5% or less, 5.0% or less, 4.5% or less, 4.0% or less, 3.5% or less, 3.0% or less, 2.5% or less, 2.0% or less, 1.5% or less, and 1.0% or less.

[0096] Y₂O₃ is also a component that helps improve weather resistance without impairing the near-infrared absorption characteristics of glass. The preferred Y₂O₃ content is 0.10% or more, with the more preferred values ​​being 0.15% or more, 0.20% or more, 0.25% or more, 0.30% or more, 0.35% or more, 0.40% or more, 0.45% or more, and 0.50% or more. On the other hand, from the viewpoint of further suppressing the reduction in visible light transmittance, the preferred Y₂O₃ content is 8.0% or less, with the more preferred values ​​being 7.0% or less, 6.5% or less, 6.0% or less, 5.5% or less, 5.0% or less, 4.5% or less, 4.0% or less, 3.5% or less, 3.0% or less, 2.5% or less, 2.0% or less, 1.5% or less, and 1.0% or less. In addition, Y₂O₃ can also be introduced from the perspective of increasing the glass mole volume without increasing the glass specific gravity.

[0097] Gd₂O₃ is also a component that helps improve weather resistance. The preferred Gd₂O₃ content is 0.10% or higher, with the following preferred values: 0.15% or higher, 0.18% or higher, and 0.21% or higher. On the other hand, from the viewpoint of further suppressing the reduction in visible light transmittance, the preferred Gd₂O₃ content is 8.0% or lower, with the following preferred values: 7.0% or lower, 6.5% or lower, 6.0% or lower, 5.5% or lower, 5.0% or lower, 4.5% or lower, 4.0% or lower, 3.5% or lower, 3.0% or lower, 2.5% or lower, 2.0% or lower, 1.5% or lower, and 1.0% or lower.

[0098] In addition, the oxide reference glass may contain one or more rare earth oxides other than those mentioned above, such as Lu2O3 and Sc2O3, or it may contain none. Because these components are generally high-priced, the content of rare earth oxides other than La2O3, Y2O3, and Gd2O3 (when there are more than two, it refers to their total content) is preferably below 2.5%, more preferably below 1.5%, 1.0%, and below 0.5%, or it may be set to 0%.

[0099] From the perspective of improving weather resistance, the total content of Al2O3, La2O3, Y2O3 and Gd2O3 in glass 1 to 6 (Al2O3 + La2O3 + Y2O3 + Gd2O3) is preferably 0.1% or more, and the preferred order is 0.15% or more, 0.20% or more, 0.25% or more, 0.30% or more, 0.35% or more, 0.40% or more, 0.45% or more, and 0.50% or more. On the other hand, from the viewpoint of ensuring the thermal stability of glass and / or reducing the melting temperature, the total content (Al2O3 + La2O3 + Y2O3 + Gd2O3) is preferably below 8.0%, and more preferably below 7.0%, below 6.5%, below 6.0%, below 5.5%, below 5.0%, below 4.5%, below 4.0%, below 3.5%, below 3.0%, below 2.5%, below 2.0%, below 1.5%, and below 1.0%.

[0100] Cations with a valence of +2 tend to have a limited effect on improving visible light transmittance and weather resistance when viewed as a whole glass composition. Therefore, the molar ratio ((MgO+CaO+SrO+BaO) / Li2O) of the total content of the oxides of the +2 cations MgO, CaO, SrO, and BaO relative to the content of the necessary cation Li ion oxide Li2O is preferably 2.0 or less, and more preferably in the following order: 1.5 or less, 1.3 or less, 1.2 or less, 1.1 or less, 1.0 or less, 0.9 or less, 0.8 or less, 0.7 or less, 0.6 or less, 0.5 or less, 0.4 or less, 0.3 or less, and 0.2 or less. As will be described later, the above components are any components that can be used when adjusting the half-value together with a portion of the alkali component.

[0101] Furthermore, from the viewpoint of improving visible light transmittance, the total content of the cation oxides with a valence of +2, namely MgO, CaO, SrO, BaO, and ZnO, relative to the content of the necessary cation Li ion oxide, Li₂O, in the molar ratio ((MgO+CaO+SrO+BaO+ZnO) / Li₂O), is preferably 2.0 or less, and more preferably 1.5 or less, 1.3 or less, 1.2 or less, 1.1 or less, 1.0 or less, 0.9 or less, 0.8 or less, 0.7 or less, 0.6 or less, 0.5 or less, 0.4 or less, 0.3 or less, and 0.2 or less. On the other hand, from the viewpoint of improving weather resistance, the molar ratio (MgO+CaO+SrO+BaO+ZnO) / Li₂O is preferably 2.0 or more, and more preferably 2.5 or more, 3.0 or more, 3.5 or more, and 4.0 or more. As described below, the above-mentioned components are any components that can be used when adjusting the half value together with some alkaline components.

[0102] The BaO content can be set to 0%. 0% or more, or even higher. BaO is a component that improves weather resistance by introducing a certain amount, and the change in T600 caused by its introduction is small. Related T600 values ​​are described later. BaO can be added to improve the thermal stability of glass and adjust its solubility. Furthermore, BaO can also be used to adjust the concentration of CuO. The preferred BaO content is 0.5% or more, with the following preferred order: 1.0% or more, 1.5% or more, 2.0% or more, 2.5% or more, 3.0% or more, 3.5% or more, 4.0% or more, 4.5% or more, 5.0% or more, 5.5% or more, 6.0% or more, 6.5% or more, and 7.0% or more. However, excessive introduction may lead to a decrease in T400. Related T400 values ​​are described later. Based on the above viewpoints, the preferred BaO content is below 36.0%, with the following order of preference: below 35.0%, below 34.0%, below 33.0%, below 32.0%, below 31.0%, below 30.0%, below 29.0%, below 28.0%, below 27.0%, below 26.0%, below 26.0%, below 25.0%, below 24.0%, below 23.0%, below 22.0%, below 21.0%, below 20.0%, below 19.0%, below 18.0%, below 17.0%, below 16.0%, below 15.0%, below 14.0%, below 13.0%, below 12.0%, below 11.0%, below 10.0%, and below 9.0%.

[0103] The SrO content can be set to 0%. 0% or more, or even higher. Similar to BaO, SrO is a component that is less likely to reduce weather resistance and can be appropriately added to adjust the thermal stability of glass. SrO can also be used to adjust the concentration of CuO. The preferred SrO content is 0.5% or more, with the following preferred order: 1.0% or more, 1.5% or more, 2.0% or more, 2.5% or more, 3.0% or more, 3.5% or more, 4.0% or more, 4.5% or more, 5.0% or more, 5.5% or more, 6.0% or more, 6.5% or more, and 7.0% or more. However, since excessive introduction tends to reduce T400, the optimal SrO content is below 30.0%, with the following preferred order: below 29.0%, below 28.0%, below 27.0%, below 26.0%, below 26.0%, below 25.0%, below 24.0%, below 23.0%, below 22.0%, below 21.0%, below 20.0%, below 19.0%, below 18.0%, below 17.0%, below 16.0%, below 15.0%, below 14.0%, below 13.0%, below 12.0%, below 11.0%, below 10.0%, and below 9.0%.

[0104] The CaO content can be set to 0%. 0% or more, or even higher, is acceptable. CaO is a component that is less likely to reduce weather resistance and can be added appropriately for reasons such as adjusting the thermal stability of glass. CaO can also be used to adjust the concentration of CuO. The preferred CaO content is 0.5% or more, with the following preferred order: 1.0% or more, 1.5% or more, 2.0% or more, 2.5% or more, 3.0% or more, 3.5% or more, 4.0% or more, 4.5% or more, 5.0% or more, 5.5% or more, 6.0% or more, 6.5% or more, and 7.0% or more. However, since excessive introduction can tend to reduce T400, the preferred CaO content is below 30.0%, with the following order of preference: below 29.0%, below 28.0%, below 27.0%, below 26.0%, below 26.0%, below 25.0%, below 24.0%, below 23.0%, below 22.0%, below 21.0%, below 20.0%, below 19.0%, below 18.0%, below 17.0%, below 16.0%, below 15.0%, below 14.0%, below 13.0%, below 12.0%, below 11.0%, below 10.0%, and below 9.0%.

[0105] Among the cations contained in the aforementioned main cation groups, Na ions, K ions, and Zn ions tend to cause deterioration of the weather resistance of glass, and therefore are quite difficult to replace the necessary cation Li ions for free use. In addition to this, from the perspective of improving the transmittance in the visible or near-infrared range, for glass 1 to 6, the total ratio of Na2O, K2O, and ZnO content ((Na2O+K2O+ZnO) / Li2O) relative to Li2O content should be 2.4 or less, preferably 2.3 or less, and even more preferably 2.2 or less, 2.1 or less, 2.0 or less, 1.9 or less, 1.8 or less, 1.7 or less, 1.6 or less, 1.5 or less, 1.4 or less, 1.3 or less, 1.2 or less, 1.1 or less, 0.9 or less, 0.8 or less, 0.7 or less, 0.6 or less, 0.5 or less, 0.4 or less, 0.3 or less, 0.2 or less, 0.1 or less, and 0.05 or less, or can be set to 0.00. On the other hand, from the viewpoint of suppressing glass raw material costs, the molar ratio ((Na2O+K2O+ZnO) / Li2O) can be set to 0, 0 or more, or greater than 0. From the viewpoint of promoting the reduction of Tg or Tm by mixing complex components, it is preferable to be 0.05 or more, or it can also be set to 0.1 or more, 0.2 or more, or 0.3 or more.

[0106] Furthermore, the higher the content of Na, K, and Zn ions, the more difficult it is to introduce more P₂O₅ to maintain weather resistance, resulting in a greater difficulty in introducing the required amount of P₂O₅. From this perspective, and as mentioned above regarding inhibiting the reduction of weather resistance, the total content of Na₂O, K₂O, and ZnO (Na₂O + K₂O + ZnO) is preferably below 30.0%, with the preferred order being below 25.0%, below 20.0%, below 15.0%, below 12.0%, below 10.0%, below 9.0%, below 8.0%, below 7.0%, below 6.0%, below 5.0%, below 4.0%, below 3.0%, below 2.0%, and below 1.0%. The above total content can also be set to 0%. On the other hand, from the perspective of suppressing the cost of glass raw materials, the total content (Na2O+K2O+ZnO) can also be set to 1.0% or more, 2.0% or more, 3.0% or more, or 5.0% or more.

[0107] The Na₂O content can be set to 0%, 0% or more, or even higher than 0%. Excessive introduction of Na₂O tends to reduce weather resistance. Therefore, the Na₂O content is preferably below 20.0%, with the preferred order being below 19.0%, below 18.0%, below 17.0%, below 16.0%, below 15.0%, below 14.0%, below 13.0%, below 12.0%, below 11.0%, below 10.0%, below 9.0%, and below 8.0%. On the other hand, besides readily available and inexpensive raw materials, Na₂O has not improved solubility and can be appropriately added. Therefore, the Na₂O content can be set, for example, above 0.5%, and further, it can be set above 1.0%, above 1.5%, above 2.0%, above 2.5%, above 3.0%, above 3.5%, above 4.0%, and above 5.0%.

[0108] The K₂O content can be set to 0%, 0% or more, or even higher than 0%. Excessive K₂O can tend to reduce weather resistance. Furthermore, it tends to cause CuO absorption wavelengths to become more concentrated, so it's best to avoid actively introducing it. From this perspective, the preferred K₂O content is below 20.0%, with the following order of preference: below 19.0%, below 18.0%, below 17.0%, below 16.0%, below 15.0%, below 14.0%, below 13.0%, below 12.0%, below 11.0%, below 10.0%, below 9.0%, and below 8.0%. On the other hand, K₂O can be added appropriately to improve glass solubility. From this perspective, the optimal K2O content is 0.2% or higher, with the following order of preference: 0.5% or higher, 1.0% or higher, 1.5% or higher, 2.0% or higher, 2.5% or higher, 3.0% or higher, 3.5% or higher, 4.0% or higher, and 5.0% or higher.

[0109] The Cs₂O content can be set to 0%, 0% or more, or even higher than 0%. Because Cs₂O tends to reduce weather resistance, it is best not to actively introduce it. The preferred order of Cs₂O content is below 15.0%, below 14.0%, below 13.0%, below 12.0%, below 11.0%, below 10.0%, below 9.0%, below 8.0%, below 7.0%, and below 6.0%. On the other hand, to adjust thermal stability and solubility, the Cs₂O content can be set to 0.5% or more, with the preferred order being above 1.0%, above 1.5%, above 2.0%, above 2.5%, above 3.0%, above 3.5%, and above 4.0%.

[0110] From the perspective of improving glass solubility, the preferred total content of Li₂O, Na₂O, and K₂O (Li₂O + Na₂O + K₂O) is 1.8% or higher, with the following preferred order: 2.1% or higher, 2.3% or higher, 2.5% or higher, 3.5% or higher, 4.5% or higher, 5.5% or higher, 6.5% or higher, 7.5% or higher, 8.5% or higher, 9.5% or higher, 10.0% or higher, and 10.5% or higher. On the other hand, from the perspective of further suppressing the reduction of weather resistance, the total content (Li₂O + Na₂O + K₂O) is preferably below 35.0%, and the preferred order is below 33.5%, below 32.5%, below 31.5%, below 30.5%, below 29.5%, below 28.5%, below 27.5%, below 26.5%, below 25.5%, below 24.5%, below 23.5%, below 21.5%, below 20.5%, below 19.5%, below 18.5%, below 17.5%, below 16.6%, below 15.5%, below 14.5%, and below 13.5%. The view that the total content (Li₂O + Na₂O + K₂O) is below the above value is better because it increases the amount of glass expansion and contraction by increasing the coefficient of thermal expansion, and avoids stress on the glass when using other components to regulate the glass volume change, which could lead to defects and cracks.

[0111] From the perspective of suppressing glass deliquescence, the preferred total content of Na₂O and K₂O (Na₂O + K₂O) is below 30.0%, with the following preferred order: below 29.0%, below 28.0%, below 27.0%, below 26.0%, below 25.0%, below 24.0%, below 23.0%, below 22.0%, below 21.0%, below 20.0%, below 19.0%, below 18.0%, below 17.0%, below 16.0%, below 15.0%, below 14.0%, below 13.0%, below 12.0%, below 11.0%, below 10.0%, below 9.0%, below 8.0%, below 7.0%, below 6.0%, below 5.0%, below 4.0%, below 3.0%, below 2.0%, below 1.0%, and below 0.5%. By setting the total content of Na₂O and K₂O (Na₂O + K₂O) to 0%, glass with better deliquescence suppression can be obtained. On the other hand, from the viewpoint of suppressing glass melting and reducing glass raw material costs while suppressing T600 reduction, the total content (Na₂O + K₂O) can be set to 1.0% or more, and further, can be set to 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, 11.0% or more, 12.0% or more, 13.0% or more, 14.0% or more, and 15.0% or more.

[0112] When adjusting the glass thickness, CuO can be replaced with other components. However, by setting the glass to have a total content of Na₂O, K₂O, CaO, SrO, and BaO (Na₂O + K₂O + CaO + SrO + BaO) of 0% or higher, the CuO concentration can be adjusted without significantly altering the near-infrared absorption position. The preferred total content (Na₂O + K₂O + CaO + SrO + BaO) is 0.5% or higher, with the following preferred order: 1.0% or higher, 1.5% or higher, 2.0% or higher, 2.5% or higher, 3.0% or higher, 3.5% or higher, 4.0% or higher, 4.5% or higher, 5.0% or higher, 5.5% or higher, 6.0% or higher, 6.5% or higher, and 7.0% or higher. However, excessive introduction tends to lower the T400, therefore the total content (Na₂O + K₂O + CaO + SrO + BaO) should be kept relatively low. The optimal concentration of O+CaO+SrO+BaO is below 36.0%, with the following order of preference: below 35.0%, below 34.0%, below 33.0%, below 32.0%, below 31.0%, below 30.0%, below 29.0%, below 28.0%, below 27.0%, below 26.0%, below 26.0%, below 25.0%, below 24.0%, below 23.0%, below 22.0%, below 21.0%, below 20.0%, below 19.0%, below 18.0%, below 17.0%, below 16.0%, below 15.0%, below 14.0%, below 13.0%, below 12.0%, below 11.0%, below 10.0%, and below 9.0%. From the perspective of maximizing the near-infrared absorption characteristics of glass, the total content (Na2O+K2O+CaO+SrO+BaO) can also be set below 8.0%, 7.0%, 6.0%, 5.0%, or 4.0%.

[0113] The relevant weather resistance can be defined as one or both of the following: inhibition of glass deliquescence and inhibition of the formation of precipitates on the glass surface under high temperature and humidity. Further details on this will be provided later. To further improve weather resistance, it is preferable to introduce Al₂O₃, followed more preferably by introducing one or more of Y₂O₃, La₂O₃, and Gd₂O₃. Furthermore, the weather resistance of BaO can be improved by introducing more of it, while SrO or CaO requires more to improve weather resistance. Therefore, the value (in moles) calculated by "(3×Al2O3 +Y2O3 +La2O3 + Gd2O3 +BaO / 3+(CaO+SrO) / 6)" is preferably 0% or more, better is more than 0%, and the better order is 0.5% or more, 1.0% or more, 2.0% or more, 3.0% or more, 4.0% or more, 5.0% or more, 6.0% or more, 7.0% or more, and 8.0% or more. Furthermore, when considering the weather resistance and mechanical strength of the glass, the preferred order is 9.0% or higher, 10.0% or higher, 11.0% or higher, 12.0% or higher, 13.0% or higher, 14.0% or higher, 15.0% or higher, 16.0% or higher, 17.0% or higher, 18.0% or higher, and 19.0% or higher. In the expression "(3×Al₂O₃ +Y₂O₃ +La₂O₃ +Gd₂O₃ +BaO / 3+(CaO+SrO) / 6)," "Al₂O₃" refers to the Al₂O₃ content, "Y₂O₃" refers to the Y₂O₃ content, "La₂O₃" refers to the La₂O₃ content, "Gd₂O₃" refers to the Gd₂O₃ content, "BaO" refers to the BaO content, "CaO" refers to the CaO content, and "SrO" refers to the SrO content. That is, "(3×Al2O3 +Y2O3 +La2O3 +Gd2O3 +BaO / 3+(CaO+SrO) / 6)" is the sum of the value calculated by three times the Al2O3 content, the Y2O3 content, the La2O3 content, the Gd2O3 content, one-third of the BaO content, and one-sixth of the combined CaO and SrO content. The value calculated in this way is expressed in % (moles). On the other hand, if the value of "(3×Al2O3 +Y2O3 +La2O3 +Gd2O3 +BaO / 3+(CaO+SrO) / 6)" is too large, there will be a tendency for the glass solubility to deteriorate, and a tendency for the near-infrared absorption position to shift towards the visible light end. Therefore, the optimal value calculated by "(3×Al2O3 +Y2O3 +La2O3 +Gd2O3 +BaO / 3+(CaO+SrO) / 6)" is 40.0% or less, and the better values ​​are 37.0% or less, 35.0% or less, 33.0% 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, and 21.0% or less.

[0114] The value calculated from "(3×Al₂O₃ +Y₂O₃ +La₂O₃ +Gd₂O₃ +BaO / 3+(CaO+SrO) / 6)" relative to the total content of P₂O₅, Li₂O, and CuO, i.e., ["(3×Al₂O₃ +Y₂O₃ +La₂O₃ +Gd₂O₃ +BaO / 3+(CaO+SrO) / 6) / (P₂O₅ +Li₂O+CuO)"], can be set to 0.0 or higher. The components selected from the group consisting of Al₂O₃, Y₂O₃, La₂O₃, Gd₂O₃, BaO, CaO, and SrO are preferably introduced in a certain amount or more relative to the necessary components P₂O₅, Li₂O, and CuO. Therefore, the preferred ratio is 0.01 or higher, with the following order of preference: 0.02 or higher, 0.03 or higher, 0.04 or higher, 0.05 or higher, 0.06 or higher, 0.07 or higher, 0.08 or higher, and 0.09 or higher. For further improvement in weather resistance, the preferred ratio is 0.10 or higher, with the following order of exceptional quality: 0.11 or higher, 0.12 or higher, 0.13 or higher, 0.14 or higher, 0.15 or higher, 0.16 or higher, 0.17 or higher, 0.18 or higher, 0.19 or higher, 0.20 or higher, 0.21 or higher, 0.22 or higher, 0.23 or higher, 0.24 or higher, or 0.25 or higher. On the other hand, if the above ratio is too large, the transmittance characteristics of the glass will decrease, and the tendency for the glass stability to decrease will also increase. Therefore, the above ratio is preferably below 0.36, and the better order is below 0.35, below 0.34, below 0.33, below 0.32, below 0.31, below 0.30, below 0.29, and below 0.28.

[0115] The ZnO content can be set to 0%, 0% or more, or even higher than 0%. ZnO is a component that can be appropriately added to adjust the thermal stability of glass, etc. However, from the viewpoint of ensuring sufficient introduction of the necessary component P2O5 without reducing the weather resistance of the glass, the upper limit of the content is preferably below 20.0%, and the preferred order is below 19.0%, below 18.0%, below 17.0%, below 16.0%, below 15.0%, below 14.0%, below 13.0%, below 12.0%, below 11.0%, below 10.0%, below 9.0%, below 8.0%, below 7.0%, below 6.0%, and below 5.0%. When the introduction effect of other components is given priority, the ZnO content can also be set below 4.0%, below 3.0%, below 2.0%, and below 1.0%. On the other hand, when ZnO is introduced to adjust the thermal stability of glass and reduce Tg and / or Tm, the preferred order is 0.4% or more, 0.6% or more, 0.8% or more, 1.0% or more, 1.2% or more, 1.4% or more, 1.6% or more, 1.8% or more, and 2.0% or more.

[0116] The glass described above is preferably composed of the aforementioned components, but may contain other components to the extent that it does not impair the effectiveness of the aforementioned components. Furthermore, the aforementioned glass does not exclude the presence of unavoidable impurities.

[0117] For example, Nb₂O₅ and ZrO₂ are components other than those mentioned above. To adjust the weather resistance, mechanical strength, or thermal stability of the glass, they can be appropriately introduced at concentrations exceeding 0%, 0.1%, or 0.2%, respectively. However, the preferred concentrations are below 5.0%, with the more preferred order being below 4.0%, below 3.0%, below 2.0%, below 1.0%, below 0.5%, and below 0.3%. The concentrations of these components can also be set to 0%.

[0118] TiO2, WO3, and Bi2O3 are also components not mentioned above. To adjust the glass's weather resistance and mechanical strength, or to improve its thermal stability, they can be appropriately introduced at concentrations exceeding 0%, 0.1%, or 0.2%, respectively, without affecting the glass's transmittance. However, their respective contents are preferably below 4.0%, with the preferred order being below 3.0%, below 2.0%, below 1.0%, below 0.5%, and below 0.3%. The contents of these components can also be set to 0%.

[0119] Pb, As, Cd, Tl, Be, and Se are all toxic. Therefore, it is best to avoid including these elements in the glass composition of the aforementioned glasses.

[0120] U, Th, and Ra are all radioactive elements. Therefore, the glass composition of the aforementioned glass should ideally not contain these elements.

[0121] V, Cr, Mn, Fe, Co, Ni, Pr, Nd, Pm, Sm, Eu, Tb, Dy, Ho, Er, and Tm increase the color of glass and can serve as sources of fluorescence. Therefore, in the aforementioned glass, the total content of the oxides of these elements in the glass reference is preferably below 10 ppm by mass, and more preferably, the glass composition does not contain these elements.

[0122] Because V₂O₅ is toxic, it is best not to use it. That is, in one form, glass 1 to 6 is preferably glass without V ions, and in the glass composition based on oxides (Mohr's standard), the V₂O₅ content is preferably less than 1.0%, more preferably less than 0.3%, less than 0.1%, less than 0.01%, and most preferably free of V₂O₅.

[0123] In one example, the ratio of V2O5 to the essential component Li2O is preferably 0.0080 or less, with the preferred order being 0.0048 or less, 0.0028 or less, 0.0018 or less, and 0.0014 or less.

[0124] Besides reducing the visible light transmittance of glass, CoO is also toxic and should therefore be avoided. Specifically, glass forms 1-6 are preferably free of Co ions, and CoO should ideally be absent from the glass composition based on oxides.

[0125] The raw materials used to incorporate Ge and Ta into glass are high-priced. Therefore, it is best if the glass composition of the aforementioned glass does not contain these substances.

[0126] Sb (Sb₂O₃), Sn (SnO₂), Ce (CeO₂), and SO₃ are elements that can be added arbitrarily and function as clarifying agents. Among them, Sb (Sb₂O₃) is a clarifying agent with a relatively strong clarifying effect. Sn (SnO2) and Ce (CeO2) have a smaller clarifying effect than Sb (Sb2O3). If these clarifying agents are added in large quantities, there is a tendency for the glass to become more colored. Therefore, when adding clarifying agents, it is best to add Sb (Sb2O3) after considering the impact on coloring.

[0127] The content of the relevant components that enable the clarifying agent function described below is expressed as a value in the glass composition based on oxides.

[0128] The Sb₂O₃ content is expressed as an additional percentage. That is, when the total content of all glass components other than Sb₂O₃, SnO₂, CeO₂, and SO₃ in oxide form is set as 100.0% by mass, the Sb₂O₃ content is preferably less than 2.0% by mass, with the preferred order being less than 1.5% by mass, less than 1.2% by mass, less than 1.0% by mass, less than 0.9% by mass, less than 0.8% by mass, less than 0.7% by mass, less than 0.6% by mass, less than 0.5% by mass, less than 0.4% by mass, less than 0.3% by mass, less than 0.2% by mass, and less than 0.1% by mass. The Sb₂O₃ content can also be 0% by mass. However, from the perspective of promoting glass oxidation and improving visible light transmittance, the Sb2O3 content can be set to 0.01% by mass or more, or 0.02% by mass or more, 0.03% by mass or more, 0.04% by mass or more, 0.05% by mass or more, 0.06% by mass or more, or 0.08% by mass or more.

[0129] The SnO2 content is also expressed as an additional percentage. That is, when the total content of all glass components other than SnO2, Sb2O3, CeO2, and SO3 in oxide form is set to 100.0% by mass, the SnO2 content is preferably less than 2.0% by mass, more preferably less than 1.0% by mass, and the particularly preferred order is below 0.9% by mass, below 0.8% by mass, below 0.7% by mass, below 0.6% by mass, below 0.5% by mass, below 0.4% by mass, below 0.3% by mass, below 0.2% by mass, and below 0.1% by mass. The SnO2 content can also be set to 0% by mass. By setting the SnO2 content within the above range, the clarity of the glass can be improved.

[0130] The CeO2 content is also expressed as an additional percentage. That is, when the total content of all glass components other than CeO2, Sb2O3, SnO2, and SO3 in oxide form is set to 100.0% by mass, the CeO2 content is preferably less than 2.0% by mass, more preferably less than 1.0% by mass, and the particularly favorable order is less than 0.9% by mass, less than 0.8% by mass, less than 0.7% by mass, less than 0.6% by mass, less than 0.5% by mass, less than 0.4% by mass, less than 0.3% by mass, less than 0.2% by mass, and less than 0.1% by mass. The CeO2 content can also be set to 0% by mass. By setting the CeO2 content within the above range, the clarity of the glass can be improved.

[0131] The SO3 content is also expressed as an additional percentage. That is, when the total content of all glass components other than SO3, Sb2O3, SnO2, and CeO2 in oxide form is set as 100.0% by mass, the preferred SO3 content is less than 2.0% by mass, more preferably less than 1.0% by mass, exceptionally good is less than 0.5% by mass, and best is less than 0.1% by mass. The SO3 content can also be set to 0% by mass. By setting the SO3 content within the above range, the clarity of the glass can be improved.

[0132] <Properties of Glass> (Penetration characteristics) The aforementioned glass system is well-suited for use as near-infrared cutoff filters. Unless otherwise stated, in this invention and this specification, "transmittance" refers to external transmittance, including reflection loss. The relevant "near-infrared cutoff capability" can be defined as follows: half-value λT 50 (which is the wavelength at which the transmittance is 50% above 550nm), transmittance T1200 at 1200nm, average transmittance in the wavelength range of 1100nm to 800nm ​​(also known as "Ave.T1100-800"), or transmittance T750 at 750nm. Furthermore, the aforementioned glass system also exhibits high transmittance in the visible light domain. The transmittance in the visible light domain can be defined as either the transmittance T400 at a wavelength of 400 nm or the transmittance T600 at a wavelength of 600 nm.

[0133] The transmittance characteristics of glass are obtained by the following method. The glass samples were processed with mutually parallel, optically polished surfaces, and their external transmittance was measured at wavelengths of 200–1200 nm. The external transmittance also includes light reflection loss from the sample surface. Let the intensity of light incident perpendicularly on one of the optically polished planes be intensity A, and the intensity of light emitted from the other plane be intensity B. Calculate the spectral transmittance B / A, including reflection loss. Let the wavelength with a spectral transmittance of 50% above 550 nm be the half-value λT 50. Let the spectral transmittance at 400 nm be T400, at 600 nm be T600, and at 1200 nm be T1200. Let the average spectral transmittance from 1100 nm to 800 nm be Ave.T1100-800, and the spectral transmittance at 750 nm be T750. Furthermore, when the glass being measured is not the glass of the thickness to be converted, the thickness of the glass is set as d, and the transmittance at each wavelength λ is converted using the following formula A. Then, various conversion values ​​can be obtained from the transmittance characteristics obtained by the conversion.

[0134] Formula A: T(λ)=(1-R(λ))2 ×exp(loge ((T0 (λ) / 100) / (1-R(λ))2 )×d / d0 )×100

[0135] 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))2, where n(λ) is the refractive index at wavelength λ. Here, n(λ) is considered as a constant with n(λ) = 1.51680 and R(λ) = 0.042165 for calculation.

[0136] The higher transmittance value (T600) in the red region and the lower transmittance value (T1200) in the near-infrared region indicate a balance between improved transmittance in the visible light region and enhanced near-infrared cutoff capability. Similarly, the higher transmittance value (T400) in the violet region also suggests improved transmittance in the visible light region. Based on the above viewpoints, the preferred ranges for T400, T600, and T1200 are as follows. For the T400, a preferred value is 70% or higher, with the following order of preference: 71% or higher, 72% or higher, 73% or higher, 74% or higher, 75% or higher, 76% or higher, 77% or higher, 78% or higher, 79% or higher, and 80% or higher. The T400 can be set to, for example, below 98%, 97%, or 96%, but since a higher T400 generally indicates better visible light transmittance, values ​​higher than the examples above are preferable. For a T600, a preferred value is 50% or higher, with the following order of preference: 55% or higher, 56%, 57% or higher, 58% or higher, 59% or higher, 60% or higher, 61% or higher, 62% or higher, 63% or higher, 64% or higher, 65% or higher, 66% or higher, 67% or higher, 68% or higher, 69% or higher, 70% or higher, 71% or higher, 72% or higher, 73% or higher, 74% or higher, and 75% or higher. A T600 can be set to, for example, below 90%, below 85%, or below 80%, but since a higher T600 generally indicates better visible light transmittance, values ​​higher than the examples above are preferred. For the relevant T1200, a preferred value is below 30%, with the following preferred values ​​in order: below 29%, below 28%, below 27%, below 26%, below 25%, below 24%, below 23%, below 22%, below 21%, below 20%, below 19%, below 18%, below 17%, below 16%, below 15%, below 14%, below 13%, below 12%, below 11%, below 10%, below 9%, below 8%, below 7%, below 6%, below 5%, below 4%, below 3%, below 2%, and below 1%. While considering visible light transmittance, T1200 can be set to, for example, above 1%, above 3%, above 5%, or above 7%. However, because a lower T1200 indicates better near-infrared cutoff capability, values ​​lower than the above examples are preferred.

[0137] In one configuration, T1200 can also be set below β1%.

[0138] The β1 series is calculated using the following formula B1. In formula B1, the R series O / P ratio is given. (Formula B1) β1=64×R-170

[0139] Furthermore, in another form, T1200 can also be set below the values ​​of β2, β3, β4, β5, and β6 shown in formulas B2 to B6 (unit: %). In the formulas below, R is the O / P ratio. Equation B2: β2 = 64 × R - 175 Formula B3: β3=64×R-180 Equation B4: β4 = 80 × R - 220 Equation B5: β5 = 80 × R - 224 Equation B6: β6 = 80 × R - 228

[0140] The half-value λT 50 (where the transmittance is 50% at wavelengths above 550nm) is preferably above 600nm, with the preferred order being above 610nm, above 613nm, above 615nm, above 617nm, above 620nm, above 623nm, above 625nm, and above 628nm. The half-value λT 50 is preferably below 650nm, with the preferred order being below 647nm, below 645nm, below 643nm, below 641nm, below 640nm, below 639nm, and below 638nm. Achieving the half-value λT 50 (where the transmittance is 50% at wavelengths above 550nm) with a glass thickness of a predetermined value is preferable from the perspective of balancing glass thinning and improved near-infrared cutoff capability. The "predetermined glass thickness" is preferably below 0.25mm.

[0141] Furthermore, because the aforementioned glass system exhibits excellent absorption characteristics in the near-infrared region, the "Ave.T1100-800" can be suppressed to below 15%. The preferred "Ave.T1100-800" is below 14%, with even better results in the following order: below 13%, below 12%, below 11%, below 10%, below 9%, below 8%, below 7%, below 6%, below 5%, below 4%, below 3%, below 2%, below 1.3%, below 1.0%, below 0.3%, below 0.1%, below 0.03%, and below 0.01%.

[0142] Furthermore, because the aforementioned glass system exhibits excellent absorption characteristics in the near-infrared region, T750 can be suppressed to below 25%. A preferred T750 is below 24%, with even better values ​​in the following order: below 23%, below 22%, below 21%, below 20%, below 19%, below 18%, below 17%, below 16%, below 15%, below 14%, below 13%, below 12%, below 11%, below 10%, below 9%, below 8%, below 7%, below 6%, below 5%, below 4%, below 3%, below 2%, below 1.3%, below 1.0%, below 0.3%, below 0.1%, below 0.03%, and below 0.01%.

[0143] As detailed below, one form of the glass is that it can be used as a near-infrared cutoff filter with a thickness of 0.25 mm or less.

[0144] For the aforementioned glass, near-infrared cutoff filter glass with a thickness reduced to 0.25 mm or less exhibits preferred transmittance characteristics, such as those described in (a) to (h). Preferably, the aforementioned glass satisfies one or more of the conditions described in (a) to (h), or two or more. By adjusting the glass composition as explained prior to implementation, glass with superior transmittance characteristics can be obtained.

[0145] (a) For wavelengths above 550 nm, the glass thickness at a wavelength λT 50, which results in an external transmittance of 50% including reflection loss, is less than 0.25 mm. Of the aforementioned thicknesses, the external transmittance of the T600 series, including reflection loss, reaches over 50% at a wavelength of 600nm, while the external transmittance of the T1200 series, including reflection loss, is below 30% at a wavelength of 1200nm.

[0146] Regarding (a) above, the glass thickness for a wavelength λT 50 (including reflection loss) of 633 nm, which results in an external transmittance of 50% at wavelengths above 550 nm, is less than 0.25 mm. Furthermore, the thickness of the related near-infrared cutoff filter is preferably within the range described later. In this respect, the same applies to (b), (e), and (f) below.

[0147] (b) For wavelengths above 550 nm, the glass thickness at 633 nm, which results in an external transmittance of 50% including reflection loss, is less than 0.25 mm. Of the aforementioned thicknesses, the external transmittance (including reflection loss) of the T600 series glass at a wavelength of 600 nm is above 50%, and the external transmittance (including reflection loss) of the T1200 series glass at a wavelength of 1200 nm is below β1%. β is the value calculated using the following formula B1. In formula B1, R represents the O / P ratio of the aforementioned glass.

[0148] (Formula B1) β1=64×R-170

[0149] As mentioned above, T1200 can also be set below β2%, β3%, β4%, β5%, or β6%.

[0150] (c) Transmittance characteristics of a thickness of 0.11 mm: the wavelength λT50, which includes reflection loss, has an external transmittance of 50% in the range of 600 nm to 650 nm. At a wavelength of 1200 nm, the external transmittance T1200, which includes reflection loss, is less than 30%, and at a wavelength of 400 nm, the external transmittance T400, which includes reflection loss, is more than 70%.

[0151] (d) Transmittance characteristics of a thickness of 0.21 mm: the wavelength λT50, which includes reflection loss, has an external transmittance of 50% in the range of 600 nm to 650 nm. At a wavelength of 1200 nm, the external transmittance T1200, which includes reflection loss, is less than 25%, and at a wavelength of 400 nm, the external transmittance T400, which includes reflection loss, is more than 70%.

[0152] (e) The thickness of the glass at a wavelength of 645 nm, which has an external transmittance of 50% including reflection loss, is less than 0.25 mm at wavelengths above 550 nm. Of the aforementioned thicknesses, the external transmittance T600, including reflection loss, reaches over 50% at a wavelength of 600nm, and the external transmittance T1200, including reflection loss, is below 30% at a wavelength of 1200nm.

[0153] (f) The glass thickness is less than 0.25 mm at a wavelength above 550 nm, where the external transmittance, including reflection loss, is 50% at a wavelength of λT 50 and 645 nm. In the aforementioned thickness, the external transmittance T600, including reflection loss, reaches more than 50% at a wavelength of 600nm, and the external transmittance T1200, including reflection loss, is less than β1% at a wavelength of 1200nm, where β1 is the value calculated by the aforementioned Equation 4.

[0154] (g) Transmittance characteristics with a thickness of 0.23 mm: the wavelength λT50, which includes reflection loss, has an external transmittance of 50% in the range of 600 nm to 650 nm; the external transmittance T1200, which includes reflection loss, is less than 18% at a wavelength of 1200 nm; and the external transmittance T400, which includes reflection loss, is more than 70% at a wavelength of 400 nm.

[0155] (h) Transmittance characteristics of a thickness of 0.25 mm: the wavelength λT 50, which includes reflection loss, has an external transmittance of 50% in the range of 600 nm to 650 nm. At a wavelength of 1200 nm, the external transmittance T1200, which includes reflection loss, is less than 16%, and at a wavelength of 400 nm, the external transmittance T400, which includes reflection loss, is more than 70%.

[0156] (Weather resistance) The aforementioned glass system exhibits excellent weather resistance by having the composition described above. Regarding weather resistance, for example, the weather resistance evaluation result obtained visually using the method described in the following embodiments can be used as an indicator. This evaluation result is preferably any one of S to D, more preferably any one of S to C, particularly preferably any one of S to B, excellently preferably S or A, and best preferably S. Furthermore, the relevant weather resistance can also be assessed using the haze value measured by a haze meter. Glass systems with superior weather resistance could be, for example, glass with a haze value of less than 15%. The relevant weather resistance is preferably S or A (preferably S) based on the visual evaluation results, and the haze value measured by the haze meter is below 15%.

[0157] (Glass transition temperature Tg, closing temperature Tm due to the endothermic reaction of melting) There is no particular limitation on the glass transition temperature of the aforementioned glass. However, from the perspective of improving the glass's meltability to increase its short-wavelength transmittance, and from the perspective of reducing the burden on the annealing furnace or forming equipment, the preferred Tg is below 450°C, and more preferably below 440°C, 430°C, 420°C, 410°C, and 400°C. From the perspective of improving the chemical durability and / or heat resistance of the glass, the preferred Tg is above 250°C, and more preferably above 260°C, 270°C, 280°C, 290°C, and 300°C.

[0158] The Tg value of glass can be controlled by adjusting the content of Li2O, Na2O, K2O or their combined content, as well as the content of ZnO, MgO, Al2O3 or their combined content.

[0159] The closing temperature Tm of the endothermic reaction of melting in the aforementioned glass is not particularly limited, but the lower the Tm, the better the solubility, and there is a tendency for devitrification to not occur in the glass even when forming with higher viscosity. Furthermore, better solubility tends to increase the transmittance of the glass in the short wavelength visible light region. From this perspective, a temperature range (Tm) below 890℃ is preferred, with the following optimal order: below 880℃, below 870℃, below 860℃, below 850℃, below 840℃, below 830℃, below 820℃, below 810℃, below 800℃, below 790℃, below 780℃, below 770℃, below 760℃, below 750℃, below 740℃, below 730℃, below 720℃, below 710℃, below 700℃, below 690℃, below 680℃, below 670℃, below 660℃, and below 650℃. There is no specific lower limit for Tm, but because excessively low Tm tends to decrease the glass's weather resistance, Tm can also be set above 500℃, above 550℃, above 580℃, above 600℃, above 620℃, and above 640℃.

[0160] The Tm value of glass can be controlled by adjusting the content of Li2O, Na2O, K2O or their combined content, as well as the content of ZnO, MgO, Al2O3 or their combined content.

[0161] (proportion) Because making the near-infrared cutoff filter lightweight allows for the lightweighting of the components or devices assembling the filter, it is preferable. In this regard, the specific gravity of the aforementioned glass is preferably 3.40 or less, with the more preferred order being 3.35 or less, 3.30 or less, 3.25 or less, 3.20 or less, 3.15 or less, 3.10 or less, 3.05 or less, 3.00 or less, 2.95 or less, 2.90 or less, 2.85 or less, 2.80 or less, 2.75 or less, 2.70 or less, 2.65 or less, and 2.60 or less. The specific gravity can be set to, for example, 2.0 or above or 2.4 or above. From the above point of view, since the specific gravity is preferably lower, it is better to be lower than the value exemplified here.

[0162] (Mole volume) There is no particular limitation on the mole volume (M / D) of the glass. However, from the perspective of increasing the amount of CuO per unit volume to improve near-infrared absorption, a smaller mole volume is preferable. The mole volume can be reduced by replacing P₂O₅, La₂O₃, Y₂O₃, Gd₂O₃, BaO, and K₂O with Li₂O. Replacing Al₂O₃, CuO, and Na₂O with Li₂O will slightly reduce it. On the other hand, even if CaO, ZnO, and SrO are replaced with Li₂O, the mole volume will not change significantly. However, replacing MgO with Li₂O tends to increase the mole volume. By considering these tendencies and adjusting the glass composition, the mole volume of the glass can be adjusted. The ideal mol volume is below 45cc / mol, with the following order of preference: below 43cc / mol, below 42cc / mol, below 41cc / mol, below 40cc / mol, below 39.5cc / mol, below 39.0cc / mol, below 38.5cc / mol, below 38.0cc / mol, and below 37.5cc / mol. On the other hand, from the viewpoint of maintaining the weather resistance of glass, the mole volume can also be increased. In this regard, the mole volume of the aforementioned glass can be set to 34.0 cc / mole or more, or for example: 35.0 cc / mole or more, 36.0 cc / mole or more, 36.5 cc / mole or more, 37.0 cc / mole or more, 37.5 cc / mole or more, 38.0 cc / mole or more, 38.5 cc / mole or more, 39.0 cc / mole or more, 39.5 cc / mole or more.

[0163] <Methods of Glass Manufacturing> The aforementioned glass is obtained by blending, melting, and shaping various glass raw materials. Related manufacturing methods are also described below.

[0164] The aforementioned near-infrared absorbing glass is well-suited for use as near-infrared cutoff filters. Furthermore, it is also well-suited for optical components other than near-infrared cutoff filters (lenses, etc.), and can be used in various glass products and can be modified in various ways.

[0165] Near-infrared cutoff filter One aspect of this invention relates to a near-infrared cutoff filter (hereinafter also simply referred to as "filter") made of the aforementioned near-infrared absorbing glass.

[0166] The glass system constituting the aforementioned filter is as described above.

[0167] The following describes a specific example of the manufacturing method for the aforementioned filter. However, the manufacturing method described below is merely illustrative and does not limit the scope of the present invention.

[0168] Slurry-molded glass is produced by appropriately using glass raw materials such as phosphates, oxides, carbonates, nitrates, sulfates, and fluorides. The raw materials are weighed according to the desired composition, mixed, and then melted in a melting vessel such as a platinum crucible at, for example, 800°C to 1100°C. To suppress the volatilization of volatile components, a lid made of platinum or similar material can be used. Furthermore, the melting process can be carried out in the atmosphere, and to suppress changes in the valence of Cu, an oxygen environment can be created, or oxygen can be foamed within the molten glass. The molten glass is then stirred and clarified to reduce bubbles (preferably to be bubble-free), forming a homogenized molten glass. Alternatively, after clarifying the glass at 900°C to 1100°C, to promote glass oxidation, the glass can be cooled to 800°C to 1000°C before obtaining the final glass. However, the melting and clarifying temperatures should preferably not be lower than the liquidus temperature of the glass over a long period.

[0169] After stirring and clarifying the molten glass, it is poured out and gradually cooled before being shaped into the desired form. If the glass is first cooled to near its liquidus temperature to increase its viscosity before pouring, convection and veining are less likely to occur, which is preferable. The cooling rate can be selected between -50℃ / hr and -1℃ / hr, or even -30℃ / hr or -10℃ / hr.

[0170] The glass can be formed using known methods such as casting, pipe casting, rolling, and stamping. The formed glass is then transferred to an annealing furnace preheated to near the glass transfer point and gradually cooled to room temperature. This process can be used to manufacture near-infrared cutoff filters.

[0171] An example of the forming method is described below. A mold is prepared consisting of: a flat and horizontal bottom surface, a pair of parallel and opposing sidewalls sandwiching the bottom surface, and a weir plate blocking one of the openings located between the sidewalls. Homogenized molten glass is cast into the mold from a platinum alloy tube at a predetermined flow rate. The cast molten glass expands within the mold, forming a glass plate of a certain width defined by the pair of sidewalls. The formed glass plate is continuously pulled out from the mold opening. By appropriately setting the forming conditions such as the shape and size of the mold and the flow rate of the molten glass, large-area and thick glass blocks can be formed. The formed glass body is transferred to an annealing furnace preheated to near the glass transition temperature and gradually cooled to room temperature. The glass body, after strain removal through gradual cooling, is subjected to machining processes such as slicing, grinding, and lapping. In this way, near-infrared cutoff filters with shapes suitable for various applications, such as plate shapes and lens shapes, can be obtained. Alternatively, a preform made of the aforementioned glass can be formed first, and then the preform can be heated and softened before being stamped (especially a precision stamping method where the final product is stamped without grinding, polishing, or other mechanical processing of the optical functional surfaces). Optical multilayer films can also be formed on the surface of the filter as needed.

[0172] The aforementioned near-infrared cutoff filter combines excellent near-infrared cutoff capability with high transmittance in the visible light range. Based on this near-infrared cutoff filter, color sensitivity correction of semiconductor imaging elements can be effectively performed.

[0173] Furthermore, the aforementioned near-infrared cut-off filter can be used in imaging devices by combining it with a semiconductor image sensor. The semiconductor image sensor incorporates semiconductor imaging elements such as CCD and CMOS within the device, and then uses a light-transmitting component to cover the light-receiving part. This light-transmitting component can be integrated with the near-infrared cut-off filter, or it can be a separate component placed in addition to the near-infrared cut-off filter.

[0174] The aforementioned camera device includes optical elements such as lenses or prisms for imaging an image of a subject on the light-receiving surface of a semiconductor image sensor.

[0175] Furthermore, based on the aforementioned near-infrared cutoff filter, a camera device with good color sensitivity correction and capable of obtaining excellent image quality can be provided.

[0176] One type of near-infrared cut-off filter described above is a near-infrared cut-off filter with a thickness of 0.25 mm or less. In recent years, with the advent of smartphones, the thickness of camera elements has significantly decreased. Consequently, there is a growing expectation for near-infrared cut-off filters to achieve performance with even thinner thicknesses. This type of near-infrared cut-off filter is well-suited for the aforementioned near-infrared cut-off filter. The thickness of the aforementioned near-infrared cut-off filter can be set to less than 0.24 mm, 0.23 mm, 0.22 mm, 0.21 mm, 0.20 mm, 0.19 mm, 0.18 mm, 0.17 mm, 0.16 mm, 0.15 mm, 0.14 mm, 0.13 mm, or 0.12 mm. The thickness of the aforementioned near-infrared cut-off filter can also be set, for example, to 0.21 mm or 0.11 mm. Furthermore, the thickness of the aforementioned near-infrared cutoff filter can be set to, for example, 0.50 mm or more, but is not limited to this. In this invention and this specification, the term "thickness" refers to the thickness of the sample in the area where the transmittance is measured, which can be measured using a thickness gauge, micrometer, etc. For example, the thickness at approximately the center of the transmitted light's path can be measured, or the thickness at multiple points within the transmitted light's spot can be measured, and then the average value can be calculated.

[0177] For the transmittance characteristics of the aforementioned near-infrared cutoff filter, please refer to the aforementioned descriptions of glass 1 to 6. Furthermore, for the physical properties of the aforementioned near-infrared cutoff filter, please also refer to the aforementioned descriptions of glass 1 to 6. [Example]

[0178] The present invention will now be described in more detail with reference to embodiments. However, the present invention is not limited to the forms described in the embodiments.

[0179] [Examples 1-66, Comparative Examples X, A-D] Glass raw materials, such as phosphates, fluorides, carbonates, nitrates, and oxides, are weighed and mixed in quantities of 150g to 300g to obtain the glass composition shown in Table 1. The mixture is then placed in a platinum or quartz crucible and melted at 800°C to 1000°C for 80 to 100 minutes. After stirring to remove bubbles and homogenize, the mixture is poured into a preheated mold and shaped into a predetermined form. The resulting glass body is transferred to an annealing furnace heated to near the glass transfer temperature and gradually cooled to room temperature. Test pieces are cut from the obtained glass, and after mirror polishing on both sides to a thickness of approximately 0.2mm, various evaluations are performed according to the following methods.

[0180] [Evaluation Method] <Penetration Characteristics> The transmittance of each test piece at wavelengths of 200–1200 nm was measured using a spectrophotometer. Based on the measurement results, the half-values ​​(unit: nm), T400, T600, T1200, and Ave.T1100–800 (unit: %) were calculated for the half-values ​​of 645 nm, 633 nm, 0.11 mm, 0.21 mm, 0.23 mm, and 0.25 mm.

[0181] <Glass transfer temperature Tg, closing temperature Tm due to the endothermic reaction of melting> The glass transition temperature Tg and the closing temperature Tm due to the endothermic reaction of melting were determined using a differential scanning calorimeter (DSC8270) manufactured by Rigaku Corporation, at a heating rate of 10°C / min. The measurement temperature range was from room temperature to 1050°C.

[0182] Specific gravity Specific gravity was determined using the Archimedes method.

[0183] <Mole volume> The mole volume is calculated from the measured specific gravity value using the aforementioned method.

[0184] <Weather Resistance Evaluation Classification> Each test piece was kept in a constant temperature and humidity chamber at 85°C and 85% relative humidity for 3.5 hours. Then, the appearance of each test piece was visually evaluated under fluorescent light. Based on the evaluation results, weather resistance was evaluated according to the following criteria. S: Very slight fogging and / or exudates were found on the surface. A: Slight fogging and / or exudates were observed on the surface. B: Fogging and / or exudates were found on the surface with slight intensity. C: Mildly observed surface dampness due to deliquescence, and / or the presence of thick exudates. D: No deliquescence was found to significantly reduce the thickness of the plate, and / or no precipitates were found to cover the glass blank. E: Deliquescence with a significant reduction in plate thickness and / or the formation of precipitates to the extent that the glass blank is not visible.

[0185] [Table 1-1] Example Comparative Example No. P2 O5 (mol%) Li₂O (mol%) CuO (mol%) Al2O3 (mol%) Y2O3 (mol%) La2O3 (mol%) Gd2O3 (mol%) Na2O (mol%) K2 O (mol%) MgO (mol%) CaO (mol%) SrO (mol%) BaO (mol%) ZnO (mol%) Example 1 61.36 10.15 26.31 1.45 0.50 0.22 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 2 59.16 10.34 26.80 1.48 0.00 0.00 0.00 0.00 0.00 2.22 0.00 0.00 0.00 0.00 Example 3 60.04 10.50 27.21 1.50 0.52 0.23 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 4 57.87 10.67 27.65 1.52 0.00 0.00 0.00 0.00 0.00 2.29 0.00 0.00 0.00 0.00 Example 5 58.76 10.83 28.08 1.55 0.54 0.23 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 6 57.56 11.15 28.90 1.60 0.55 0.24 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 7 56.61 10.99 28.48 1.57 0.00 0.00 0.00 0.00 0.00 2.35 0.00 0.00 0.00 0.00 Example 8 57.72 7.87 30.59 0.00 2.68 1.14 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 9 56.73 10.31 30.06 0.00 2.03 0.87 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 10 57.22 9.10 30.32 0.00 2.36 1.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 11 58.23 6.62 30.86 0.00 3.01 1.29 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 12 56.24 11.50 29.81 0.00 1.72 0.73 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 13 56.24 11.50 29.81 0.00 1.47 0.98 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 14 56.24 11.50 29.81 0.00 1.96 0.49 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 15 56.24 11.50 29.81 0.00 2.20 0.25 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 16 56.24 11.50 29.81 0.00 2.45 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 17 56.24 11.50 29.80 0.83 1.14 0.49 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 18 56.24 11.50 29.80 1.23 0.86 0.37 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 19 56.24 11.50 29.80 0.42 1.43 0.61 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 20 56.24 11.50 29.80 1.65 0.25 0.57 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 21 56.24 11.50 29.80 1.65 0.57 0.25 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 22 56.24 11.50 29.80 2.46 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 23 55.33 16.23 24.40 1.62 0.00 0.00 0.00 0.00 0.00 2.42 0.00 0.00 0.00 0.00 Example 24 55.33 11.31 29.32 1.62 0.00 0.00 0.00 0.00 0.00 2.42 0.00 0.00 0.00 0.00 Example 25 56.24 11.50 21.44 1.65 0.57 0.25 0.00 0.00 0.00 0.00 0.00 0.00 8.37 0.00 Example 26 56.24 11.50 22.48 1.65 0.57 0.25 0.00 0.00 0.00 0.00 0.00 0.00 7.33 0.00 Example 27 56.24 20.55 20.76 1.65 0.57 0.25 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 28 56.24 19.87 21.44 1.65 0.57 0.25 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 29 53.59 15.72 23.64 0.00 0.00 0.00 0.00 0.00 0.00 2.35 0.00 0.00 4.71 0.00 Example 30 53.59 15.72 23.64 0.00 0.00 0.00 0.00 0.00 0.00 4.70 0.00 0.00 2.35 0.00

[0186] [Table 1-2] Example Comparative Example No. P2 O5 (mol%) Li₂O (mol%) CuO (mol%) Al2O3 (mol%) Y2O3 (mol%) La2O3 (mol%) Gd2O3 (mol%) Na2O (mol%) K2 O (mol%) MgO (mol%) CaO (mol%) SrO (mol%) BaO (mol%) ZnO (mol%) Example 31 53.59 9.23 23.64 0.00 0.00 0.00 0.00 0.00 0.00 0.00 13.55 0.00 0.00 0.00 Example 32 53.59 9.23 23.64 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 13.55 0.00 0.00 Example 33 53.59 9.23 23.64 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 13.55 0.00 Example 34 56.35 9.71 31.37 2.57 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 35 54.44 15.97 24.01 0.80 0.00 0.00 0.00 0.00 0.00 4.78 0.00 0.00 0.00 0.00 Example 36 55.27 11.75 30.46 1.68 0.58 0.25 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 37 54.34 11.56 29.97 1.65 0.00 0.00 0.00 0.00 0.00 2.48 0.00 0.00 0.00 0.00 Example 38 57.72 10.66 25.97 5.65 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 39 54.63 10.09 32.61 2.67 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 40 54.17 12.04 31.21 1.73 0.60 0.26 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 41 53.19 12.30 31.88 1.76 0.61 0.26 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 42 55.89 16.92 21.29 5.90 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 43 55.89 22.72 15.49 5.90 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 44 52.07 8.48 26.70 2.25 0.00 0.00 0.00 2.56 5.11 0.83 0.00 0.00 1.64 0.37 Example 45 55.42 22.23 15.48 5.90 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.96 Example 46 52.18 12.56 32.56 1.80 0.62 0.27 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 47 52.89 23.50 16.37 6.24 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.02 Example 48 50.85 25.32 17.26 6.57 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 49 50.32 24.78 17.26 6.58 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.07 Example 50 51.36 5.60 26.83 1.48 0.00 0.00 0.00 4.28 8.57 0.54 0.00 0.00 1.08 0.25 Example 51 52.52 21.41 14.07 5.68 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 6.33 Example 52 49.60 19.99 13.70 5.31 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 11.40 Example 53 56.24 8.50 32.80 1.65 0.57 0.25 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 54 56.24 5.50 35.80 1.65 0.57 0.25 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 55 56.24 2.50 38.80 1.65 0.57 0.25 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Example 56 53.66 15.03 14.16 3.98 0.00 0.00 0.00 2.71 5.42 1.46 0.00 0.00 2.92 0.66 Example 57 52.92 12.01 14.23 3.18 0.00 0.00 0.00 4.54 9.09 1.17 0.00 0.00 2.33 0.52 Example 58 52.18 8.95 14.31 2.37 0.00 0.00 0.00 6.40 12.79 0.87 0.00 0.00 1.74 0.39 Example 59 53.59 15.72 23.64 0.00 0.00 0.00 0.00 0.00 0.00 7.05 0.00 0.00 0.00 0.00 Example 60 53.59 9.23 23.64 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 13.55 Compare X 50.67 2.76 14.45 0.73 0.00 0.00 0.00 10.15 20.30 0.27 0.00 0.00 0.54 0.12 Compare A 53.59 19:30 27.11 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Compare B 53.59 12.73 33.68 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Compare C 53.59 22.77 23.64 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Compare D 36.07 23.63 9.87 3.32 0.00 0.00 0.00 0.00 10.45 2.74 5.31 1.99 6.61 0.00

[0187] [Table 1-3] Example Comparative Example No. P2 O5 (mol%) Li₂O (mol%) CuO (mol%) Al2O3 (mol%) Y2O3 (mol%) La2O3 (mol%) Gd2O3 (mol%) Na2O (mol%) K2 O (mol%) MgO (mol%) CaO (mol%) SrO (mol%) BaO (mol%) ZnO (mol%) Example 61 51.65 1.09 16.9 1.66 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 28.63 0.00 Example 62 51.16 1.10 16.2 1.50 0.44 0.20 0.00 0.00 0.00 0.00 0.00 0.00 29.40 0.00 Example 63 53.00 1.28 17.7 2.97 0.00 0.00 0.00 0.00 2.63 0.00 0.00 0.00 22.34 0.00 Example 64 51.16 1.16 20.7 1.50 0.44 0.20 0.00 0.00 0.00 0.00 0.00 0.00 24.85 0.00 Example 65 50.60 0.40 17.8 2.80 0.46 0.21 0.00 0.00 0.80 0.00 0.00 0.00 26.89 0.00 Example 66 50.79 0.40 17.82 1.53 0.99 0.46 0.00 0.00 0.78 0.00 0.00 0.00 27.19 0.00

[0188] [Table 2-1] Example Comparative Example No. B2O3 (mol%) SiO2 (mol%) Ta2 O5 (mol%) TiO2 (mol%) ZrO2 (mol%) Nb2O5 (mol%) WO3 (mol%) Bi2O3 (mol%) Cs2 O (mol%) V2 O5 (mol%) total (mol%) Molecular weight M (g / mol) proportion (g / cc) Mole volume (cc / mol) Composed of main cations Selected from the group Number of cationic components O / P ratio Major cations Total content of oxides (mo%) O ion content (anion%) Example 1 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 114.39 2.78 41.103 6 2.850 100.00 100.00 Example 2 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 110.79 2.78 39.823 5 2.870 100.00 100.00 Example 3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 113.45 2.80 40.517 6 2.870 100.00 100.00 Example 4 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 109.80 2.80 39.202 5 2.890 100.00 100.00 Example 5 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 112.54 2.82 39.908 6 2.890 100.00 100.00 Example 6 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 111.68 2.84 39.379 6 2.910 100.00 100.00 Example 7 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 108.84 2.82 38.583 5 2.911 100.00 100.00 Example 8 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 118.39 2.94 40.269 5 2.933 100.00 100.00 Example 9 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 114.93 2.91 39.537 5 2.933 100.00 100.00 Example 10 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 116.65 2.93 39.866 5 2.933 100.00 100.00 Example 11 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 120.17 2.95 40.679 5 2.933 100.00 100.00 Example 12 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 113.25 2.89 39.132 5 2.933 100.00 100.00 Example 13 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 113.49 2.90 39.149 5 2.933 100.00 100.00 Example 14 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 113.01 2.89 39.117 5 2.933 100.00 100.00 Example 15 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 112.76 2.88 39.140 5 2.933 100.00 100.00 Example 16 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 112.51 2.88 39.122 4 2.933 100.00 100.00 Example 17 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 112.00 2.88 38.914 6 2.933 100.00 100.00 Example 18 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 111.36 2.87 38.843 6 2.933 100.00 100.00 Example 19 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 112.62 2.89 39.023 6 2.933 100.00 100.00 Example 20 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 111.06 2.87 38.697 6 2.933 100.00 100.00 Example 21 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 110.74 2.86 38.719 6 2.933 100.00 100.00 Example 22 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 109.48 2.84 38.522 4 2.933 100.00 100.00 Example 23 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 105.42 2.77 38.113 5 2.933 100.00 100.00 Example 24 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 107.86 2.84 38.020 5 2.933 100.00 100.00 Example 25 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 116.92 2.95 39.606 7 2.933 100.01 100.00 Example 26 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 116.15 2.94 39.494 7 2.933 100.01 100.00 Example 27 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 106.25 2.73 38.962 6 2.933 100.01 100.00 Example 28 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 106.59 2.74 38.957 6 2.933 100.01 100.00 Example 29 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 107.73 2.87 37.602 5 2.933 100.00 100.00 Example 30 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 105.07 2.81 37.378 5 2.933 100.00 100.00

[0189] [Table 2-2] Example Comparative Example No. B2O3 (mol%) SiO2 (mol%) Ta2 O5 (mol%) TiO2 (mol%) ZrO2 (mol%) Nb2O5 (mol%) WO3 (mol%) Bi2O3 (mol%) Cs2 O (mol%) V2 O5 (mol%) total (mol%) Molecular weight M (g / mol) proportion (g / cc) Mole volume (cc / mol) Composed of main cations Selected from the group Number of cationic components O / P ratio Major cations Total content of oxides (mo%) O ion content (anion%) Example 31 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 105.22 2.80 37.606 4 2.933 100.00 100.00 Example 32 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 111.66 2.98 37.446 4 2.933 100.00 100.00 Example 33 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 118.40 3.09 38.316 4 2.933 100.00 100.00 Example 34 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 110.46 2.87 38.448 4 2.933 100.00 100.00 Example 35 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 103.89 2.76 37.601 5 2.933 100.00 100.00 Example 36 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 110.05 2.87 38.305 6 2.950 100.00 100.00 Example 37 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 107.11 2.85 37.530 5 2.951 100.00 100.00 Example 38 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 111.54 2.83 39.440 4 2.964 100.00 100.00 Example 39 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 109.22 2.90 37.677 4 2.964 100.00 100.00 Example 40 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 109.27 2.90 37.730 6 2.971 100.00 100.00 Example 41 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 108.56 2.91 37.256 6 2.990 100.00 100.00 Example 42 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 107.34 2.77 38.794 4 3.000 100.00 100.00 Example 43 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 104.46 2.68 38.935 4 3.000 100.00 100.00 Example 44 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 109.52 2.88 38.095 9 3.004 100.00 100.00 Example 45 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 104.43 2.70 38.676 5 3.009 100.00 100.00 Example 46 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 107.85 2.94 36.745 6 3.010 100.00 100.00 Example 47 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 102.29 2.73 37.484 5 3.063 100.00 100.00 Example 48 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 100.17 2.74 36.560 4 3.113 100.00 100.00 Example 49 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 100.13 2.76 36.253 5 3.124 100.00 100.00 Example 50 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 110.24 2.85 38.695 9 3.002 100 100.00 Example 51 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 103.07 2.76 37.414 5 3.060 100 100.00 Example 52 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 101.97 2.83 36.019 5 3.115 100 100.00 Example 53 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 112.23 2.93 38.290 6 2.933 100.00 100.00 Example 54 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 113.72 2.95 38.509 6 2.933 100.00 100.00 Example 55 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 115.21 2.97 38.751 6 2.933 100.00 100.00 Example 56 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 108.37 2.75 39.421 9 3.006 100.00 100.00 Example 57 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 109.12 2.73 40.046 9 3.005 100 100.00 Example 58 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 109.89 2.70 40.670 9 3.004 100 100.00 Example 59 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 102.41 2.76 37.091 4 2.933 100.00 100.00 Example 60 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 108.65 2.90 37.505 4 2.933 100.00 100.00 Compare X 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 111.44 2.66 41.958 9 3.001 100 100.00 Compare A 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 103.40 2.79 37.113 3 2.933 100 100.00 Compare B 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 106.66 2.89 36.882 3 2.933 100 100.00 Compare C 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 101.67 2.73 37.243 3 2.933 100 100.00 Compare D 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 95.62 2.95 32.413 9 3.478 99.99 100.00

[0190] [Table 2-3] Example Comparative Example No. B2O3 (mol%) SiO2 (mol%) Ta2 O5 (mol%) TiO2 (mol%) ZrO2 (mol%) Nb2O5 (mol%) WO3 (mol%) Bi2O3 (mol%) Cs2 O (mol%) V2 O5 (mol%) total (mol%) Molecular weight M (g / mol) proportion (g / cc) Mole volume (cc / mol) Composed of main cations Selected from the group Number of cationic components O / P ratio Major cations Total content of oxides (mo%) O ion content (anion%) Example 61 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100.0 132.70 3.40 39.03 5 3.00 100 100.00 Example 62 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100.0 134.06 3.42 39.24 7 3.02 100 100.00 Example 63 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100.0 129.49 3.25 39.84 6 3.00 100 100.00 Example 64 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100.0 130.67 3.39 38.55 7 3.02 100 100.00 Example 65 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100.0 132.70 3.39 39.14 8 3.06 100 100.00 Example 66 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100.0 134.10 3.43 39.10 8 3.04 100 100.00

[0191] [Table 3-1] Example Comparative Example No. MgO + Al2O3 (mol%) (Na₂O + K₂O + ZnO) / Li₂O O(P) O (others) O(P)- O (others) A1 = (O(P)-O(others))×Cu A2 = (O(P)-O(others))×C C (mmol / cc) α1 = 70400×exp(-2.855×R) α2 = 76522×exp(-2.855×R) C = 3200 × exp(-2.278 × R) C = 3478 × exp(-2.278 × R) Example 1 1.45 0.00 306.788 42.994 263.794 6941.68 1688.85 6.40 20.58 22.37 1.56 1.14 Example 2 3.69 0.00 295.806 43.795 252.011 6754.91 1696.23 6.73 19.45 21.14 2.10 1.70 Example 3 1.50 0.00 300.182 44.464 255.718 6959.24 1717.61 6.72 19.44 21.13 2.09 1.69 Example 4 3.81 0.00 289.362 45.177 244.185 6751.70 1722.29 7.05 18.36 19.96 2.63 2.25 Example 5 1.55 0.00 293.822 45.880 247.942 6962.41 1744.62 7.04 18.36 19.95 2.61 2.23 Example 6 1.60 0.00 287.781 47.224 240.557 6952.94 1765.65 7.34 17.34 18.85 3.11 2.75 Example 7 3.92 0.00 283.059 46.529 236.530 6735.74 1745.78 7.38 17.31 18.81 3.16 2.79 Example 8 0.00 0.00 288.584 49.934 238.650 7299.89 1812.77 7.60 16.27 17.69 3.58 3.23 Example 9 0.00 0.00 283.629 49.077 234.552 7051.39 1783.51 7.60 16.27 17.69 3.59 3.24 Example 10 0.00 0.00 286.085 49.502 236.583 7174.03 1799.55 7.61 16.27 17.69 3.59 3.24 Example 11 0.00 0.00 291.127 50.374 240.752 7429.10 1826.26 7.59 16.27 17.69 3.57 3.22 Example 12 0.00 0.00 281.214 48.660 232.554 6931.77 1771.40 7.62 16.27 17.69 3.60 3.25 Example 13 0.00 0.00 281.214 48.660 232.554 6931.77 1770.60 7.61 16.27 17.69 3.60 3.25 Example 14 0.00 0.00 281.214 48.660 232.554 6931.77 1772.07 7.62 16.27 17.69 3.60 3.25 Example 15 0.00 0.00 281.214 48.660 232.554 6931.77 1771.03 7.62 16.27 17.69 3.60 3.25 Example 16 0.00 0.00 281.214 48.660 232.554 6931.77 1771.83 7.62 16.27 17.69 3.60 3.25 Example 17 0.83 0.00 281.190 48.681 232.509 6929.83 1780.78 7.66 16.26 17.67 3.64 3.30 Example 18 1.23 0.00 281.190 48.681 232.509 6929.83 1784.07 7.67 16.26 17.67 3.66 3.31 Example 19 0.42 0.00 281.190 48.681 232.509 6929.83 1775.82 7.64 16.26 17.67 3.62 3.27 Example 20 1.65 0.00 281.176 48.694 232.482 6928.69 1790.50 7.70 16.25 17.67 3.69 3.34 Example 21 1.65 0.00 281.176 48.694 232.482 6928.69 1789.47 7.70 16.25 17.67 3.68 3.33 Example 22 2.46 0.00 281.176 48.694 232.482 6928.69 1798.65 7.74 16.25 17.67 3.72 3.37 Example 23 4.04 0.00 276.631 47.908 228.724 5581.61 1464.50 6.40 16.25 17.67 2.39 2.04 Example 24 4.04 0.00 276.631 47.908 228.724 6706.50 1763.95 7.71 16.25 17.67 3.70 3.35 Example 25 1.65 0.00 281.176 48.700 232.475 4984.27 1258.45 5.41 16.25 17.67 1.40 1.05 Example 26 1.65 0.00 281.176 48.700 232.475 5226.04 1323.27 5.69 16.25 17.67 1.68 1.33 Example 27 1.65 0.00 281.176 48.703 232.473 4826.13 1238.69 5.33 16.25 17.66 1.32 0.97 Example 28 1.65 0.00 281.176 48.703 232.473 4984.21 1279.42 5.50 16.25 17.66 1.49 1.14 Example 29 2.35 0.00 267.943 46.411 221.532 5236.32 1392.58 6.29 16.25 17.66 2.27 1.92 Example 30 4.70 0.00 267.943 46.411 221.532 5236.32 1400.92 6.32 16.25 17.66 2.31 1.96

[0192] [Table 3-2] Example Comparative Example No. MgO + Al2O3 (mol%) (Na₂O + K₂O + ZnO) / Li₂O O(P) O (others) O(P)- O (others) A1 = (O(P)-O(others))×Cu A2 = (O(P)-O(others))×C C (mmol / cc) α1 = 70400×exp(-2.855×R) α2 = 76522×exp(-2.855×R) C = 3200 × exp(-2.278 × R) C = 3478 × exp(-2.278 × R) Example 31 0.00 0.00 267.941 46.412 221.529 5236.22 1392.38 6.29 16.25 17.66 2.27 1.92 Example 32 0.00 0.00 267.941 46.412 221.529 5236.22 1398.36 6.31 16.25 17.66 2.30 1.95 Example 33 0.00 0.00 267.941 46.412 221.529 5236.22 1366.59 6.17 16.25 17.66 2.16 1.81 Example 34 2.57 0.00 281.732 48.803 232.929 7307.34 1900.57 8.16 16.25 17.66 4.15 3.80 Example 35 5.58 0.00 272.206 47.158 225.048 5404.06 1437.23 6.39 16.25 17.66 2.37 2.03 Example 36 1.68 0.00 276.361 49.765 226.596 6901.85 1801.82 7.95 15.47 16.82 4.09 3.76 Example 37 4.13 0.00 271.708 48.963 222.745 6675.06 1778.59 7.98 15.46 16.80 4.13 3.79 Example 38 5.65 0.00 288.611 53.583 235.027 6102.88 1547.37 6.58 14.87 16.16 2.85 2.52 Example 39 2.67 0.00 273.160 50.715 222.445 7253.18 1925.11 8.65 14.87 16.16 4.92 4.59 Example 40 1.73 0.00 270.861 50.989 219.872 6861.75 1818.65 8.27 14.60 15.87 4.59 4.27 Example 41 1.76 0.00 265.938 52.084 213.854 6817.32 1829.86 8.56 13.83 15.03 5.03 4.72 Example 42 5.90 0.00 279.470 55.902 223.567 4759.86 1226.95 5.49 13.42 14.59 2.04 1.74 Example 43 5.90 0.00 279.470 55.902 223.567 3462.51 889.32 3.98 13.42 14.59 0.53 0.23 Example 44 3.07 0.95 260.326 52.432 207.894 5550.91 1457.13 7.01 13.29 14.44 3.59 3.29 Example 45 5.90 0.04 277.099 56.381 220.717 3417.79 883.69 4.00 13.09 14.23 0.63 0.33 Example 46 1.80 0.00 260.911 53.203 207.708 6763.62 1840.69 8.86 13.05 14.19 5.49 5.20 Example 47 6.24 0.04 264.427 59.587 204.841 3352.26 894.33 4.37 11.20 12.18 1.38 1.12 Example 48 6.57 0.00 254.242 62.297 191.945 3312.83 906.14 4.72 9.73 10.58 2.06 1.82 Example 49 6.58 0.04 251.589 62.834 188.756 3257.36 898.50 4.76 9.41 10.23 2.17 1.94 Example 50 2.03 2.340 256.801 51.606 205.195 5505.96 1422.93 6.93 13.33 14.49 3.51 3.21 Example 51 5.68 0.296 262.591 58.844 203.746 2865.91 766.008 3.76 11.30 12.28 0.76 0.50 Example 52 5.31 0.570 248.020 61.007 187.013 2561.40 711.130 3.80 9.67 10.51 1.15 0.92 Example 53 1.65 0.00 281.176 48.694 232.482 7626.14 1991.702 8.57 16.25 17.67 4.55 4.20 Example 54 1.65 0.00 281.176 48.694 232.482 8323.58 2161.474 9.30 16.25 17.67 5.28 4.93 Example 55 1.65 0.00 281.176 48.694 232.482 9021.03 2327.952 10.01 16.25 17.67 6.00 5.65 Example 56 5.44 0.585 268.282 54.313 213.969 3029.48 768.50 3.59 13.19 14.34 0.19 -0.10 Example 57 4.35 1.179 264.610 53.447 211.163 3005.00 750.39 3.55 13.23 14.38 0.15 -0.15 Example 58 3.24 2.187 260.892 52.570 208.322 2980.18 732.77 3.52 13.28 14.43 0.1019 -0.20 Example 59 7.05 0.00 267.943 46.411 221.532 5236.32 1411.74 6.37 16.25 17.66 2.36 2.01 Example 60 0.00 1.47 267.941 46.412 221.529 5236.22 1396.15 6.30 16.25 17.66 2.29 1.94 Compare X 1.00 11.073 253.360 50.793 202.567 2927.50 697.72 3.44 13.38 14.54 0.009 -0.29 Compare A 0.00 0.000 267.943 46.411 221.532 6005.22 7.30 16.25 17.66 3.29 2.94 Compare B 0.00 0.000 267.943 46.411 221.532 7461.36 9.13 16.25 17.66 5.12 4.77 Compare C 0.00 0.000 267.943 46.411 221.532 5236.32 6.35 16.25 17.66 2.33 1.99 Compare D 6.06 0.44 180.350 70.560 109.790 1083.63 3.05 3.43 3.73 1.89 1.78

[0193] [Table 3-3] Example Comparative Example No. MgO + Al2O3 (mol%) (Na₂O + K₂O + ZnO) / Li₂O O(P) O (others) O(P)- O (others) A1 = (O(P)-O(others))×Cu A2 = (O(P)-O(others))×C C (mmol / cc) α1 = 70400×exp(-2.855×R) α2 = 76522×exp(-2.855×R) C = 3200 × exp(-2.278 × R) C = 3478 × exp(-2.278 × R) Example 61 1.45 0.00 258.228 51.64 206.59 3498.49 896.34 4.34 13.42 14.59 0.894 0.595 Example 62 1.48 0.00 255.780 53.08 202.70 3275.81 834.73 4.12 12.68 13.78 0.827 0.541 Example 63 1.50 2.06 265.000 52.91 212.09 3762.61 944.35 4.45 13.42 14.59 1.008 0.708 Example 64 1.52 0.00 255.803 53.08 202.72 4188.47 1086.61 5.36 12.68 13.78 2.061 1.774 Example 65 1.55 1.98 252.999 56.34 196.66 3509.55 896.57 4.56 11.47 12.47 1.520 1.256 Example 66 1.60 1.96 253.970 55.13 198.84 3542.58 906.10 4.56 11.87 12.90 1.433 1.162

[0194] [Table 4-1] Example Comparative Example No. B₂O₃ +SiO₂ (mol%) P₂O₅ + Li₂O + CuO (mol%) Li₂O + Na₂O + K₂O (mol%) Na₂O + K₂O (mol%) Na₂O + K₂O + CaO +SrO+BaO (mol%) Al₂O₃ + Y₂O₃ + La₂O₃ +Gd₂O₃ (mol%) (3×Al2 O3 +Y2 O3 +La2 O3 +Gd2 O3 + BaO / 3+(CaO+SrO) / 6) (mol%) (3×Al2 O3 +Y2 O3 +La2 O3 +Gd2 O3 + BaO / 3+(CaO+SrO) / 6) / (P₂O₅ + Li₂O + CuO) O ions (oxides) Coefficient × Cation (mole) Example 1 0.00 97.82 10.15 0.00 0.00 2.18 5.09 0.052 349.78 Example 2 0.00 96.31 10.34 0.00 0.00 1.48 4.43 0.046 339.60 Example 3 0.00 97.75 10.50 0.00 0.00 2.25 5.26 0.054 344.65 Example 4 0.00 96.19 10.67 0.00 0.00 1.52 4.57 0.048 334.54 Example 5 0.00 97.68 10.83 0.00 0.00 2.32 5.43 0.056 339.70 Example 6 0.00 97.61 11.15 0.00 0.00 2.39 5.59 0.057 335.00 Example 7 0.00 96.08 10.99 0.00 0.00 1.57 4.71 0.049 329.59 Example 8 0.00 96.17 7.87 0.00 0.00 3.83 3.83 0.040 338.52 Example 9 0.00 97.10 10.31 0.00 0.00 2.90 2.90 0.030 332.71 Example 10 0.00 96.64 9.10 0.00 0.00 3.36 3.36 0.035 335.59 Example 11 0.00 95.70 6.62 0.00 0.00 4.30 4.30 0.045 341.50 Example 12 0.00 97.55 11.50 0.00 0.00 2.45 2.45 0.025 329.87 Example 13 0.00 97.55 11.50 0.00 0.00 2.45 2.45 0.025 329.87 Example 14 0.00 97.55 11.50 0.00 0.00 2.45 2.45 0.025 329.87 Example 15 0.00 97.55 11.50 0.00 0.00 2.45 2.45 0.025 329.87 Example 16 0.00 97.55 11.50 0.00 0.00 2.45 2.45 0.025 329.87 Example 17 0.00 97.54 11.50 0.00 0.00 2.46 4.11 0.042 329.87 Example 18 0.00 97.54 11.50 0.00 0.00 2.46 4.93 0.051 329.87 Example 19 0.00 97.54 11.50 0.00 0.00 2.46 3.29 0.034 329.87 Example 20 0.00 97.54 11.50 0.00 0.00 2.46 5.76 0.059 329.87 Example 21 0.00 97.54 11.50 0.00 0.00 2.46 5.76 0.059 329.87 Example 22 0.00 97.54 11.50 0.00 0.00 2.46 7.39 0.076 329.87 Example 23 0.00 95.96 16.23 0.00 0.00 1.62 4.85 0.051 324.54 Example 24 0.00 95.96 11.31 0.00 0.00 1.62 4.85 0.051 324.54 Example 25 0.00 89.17 11.50 0.00 8.37 2.46 8.55 0.096 329.88 Example 26 0.00 90.21 11.50 0.00 7.33 2.46 8.20 0.091 329.88 Example 27 0.00 97.55 20.55 0.00 0.00 2.46 5.76 0.059 329.88 Example 28 0.00 97.55 19.87 0.00 0.00 2.46 5.76 0.059 329.88 Example 29 0.00 92.95 15.72 0.00 4.71 0.00 1.57 0.017 314.35 Example 30 0.00 92.95 15.72 0.00 2.35 0.00 0.78 0.008 314.35

[0195] [Table 4-2] Example Comparative Example No. B₂O₃ +SiO₂ (mol%) P₂O₅ + Li₂O + CuO (mol%) Li₂O + Na₂O + K₂O (mol%) Na₂O + K₂O (mol%) Na₂O + K₂O + CaO +SrO+BaO (mol%) Al₂O₃ + Y₂O₃ + La₂O₃ +Gd₂O₃ (mol%) (3×Al2 O3 +Y2 O3 +La2 O3 +Gd2 O3 + BaO / 3+(CaO+SrO) / 6) (mol%) (3×Al₂O₃ +Y₂O₃ +La₂O₃ + Gd₂O₃ + BaO / 3 + (CaO + SrO) / 6) / (P₂O₅ + Li₂O + CuO) O ions (oxides) Coefficient × Cation (mole) Example 31 0.00 86.45 9.23 0.00 13.55 0.00 2.26 0.026 314.35 Example 32 0.00 86.45 9.23 0.00 13.55 0.00 2.26 0.026 314.35 Example 33 0.00 86.45 9.23 0.00 13.55 0.00 4.52 0.052 314.35 Example 34 0.00 97.43 9.71 0.00 0.00 2.57 7.72 0.079 330.53 Example 35 0.00 94.42 15.97 0.00 0.00 0.80 2.40 0.025 319.36 Example 36 0.00 97.48 11.75 0.00 0.00 2.52 5.89 0.060 326.13 Example 37 0.00 95.87 11.56 0.00 0.00 1.65 4.96 0.052 320.67 Example 38 0.00 94.35 10.66 0.00 0.00 5.65 16.96 0.180 342.19 Example 39 0.00 97.33 10.09 0.00 0.00 2.67 8.02 0.082 323.88 Example 40 0.00 97.42 12.04 0.00 0.00 2.58 6.03 0.062 321.85 Example 41 0.00 97.36 12.30 0.00 0.00 2.64 6.16 0.063 318.02 Example 42 0.00 94.10 16.92 0.00 0.00 5.90 17.69 0.188 335.37 Example 43 0.00 94.10 22.72 0.00 0.00 5.90 17.69 0.188 335.37 Example 44 0.00 87.24 16.15 7.67 9.32 2.25 7.29 0.084 312.76 Example 45 0.00 93.14 22.23 0.00 0.00 5.90 17.70 0.190 333.48 Example 46 0.00 97.31 12.56 0.00 0.00 2.69 6.29 0.065 314.11 Example 47 0.00 92.75 23.50 0.00 0.00 6.24 18.71 0.202 324.01 Example 48 0.00 93.43 25.32 0.00 0.00 6.57 19.72 0.211 316.54 Example 49 0.00 92.35 24.78 0.00 0.00 6.58 19.73 0.214 314.42 Example 50 0.00 83.79 18.45 12.85 13.94 1.48 4.81 0.057 308.41 Example 51 0.00 87.99 21.41 0.00 0.00 5.68 17.04 0.194 321.43 Example 52 0.00 83.29 19.99 0.00 0.00 5.31 15.92 0.191 309.03 Example 53 0.00 97.54 8.50 0.00 0.00 2.46 5.76 0.059 329.87 Example 54 0.00 97.54 5.50 0.00 0.00 2.46 5.76 0.059 329.87 Example 55 0.00 97.54 2.50 0.00 0.00 2.46 5.76 0.059 329.87 Example 56 0.00 82.84 23.16 8.14 11.06 3.98 12.93 0.156 322.60 Example 57 0.00 79.16 25.64 13.63 15.96 3.18 10.33 0.131 318.06 Example 58 0.00 75.44 28.14 19.19 20.93 2.37 7.70 0.102 313.46 Example 59 0.00 92.95 15.72 0.00 0.00 0.00 0.00 0.000 314.35 Example 60 0.00 86.45 9.23 0.00 0.00 0.00 0.00 0.000 314.35 Compare X 0.00 67.89 33.22 30.46 30.99 0.73 2.38 0.035 304.15 Compare A 0.00 100.00 19:30 0.00 0.00 0.00 0.00 0.000 314.35 Compare B 0.00 100.00 12.73 0.00 0.00 0.00 0.00 0.000 314.35 Compare C 0.00 100.00 22.77 0.00 0.00 0.00 0.00 0.000 314.35 Compare D 0.00 69.57 34.08 10.45 24.36 3.32 13.38 0.192 250.91

[0196] [Table 4-3] Example Comparative Example No. B₂O₃ +SiO₂ (mol%) P₂O₅ + Li₂O + CuO (mol%) Li₂O + Na₂O + K₂O (mol%) Na₂O + K₂O (mol%) Na₂O + K₂O + CaO +SrO+BaO (mol%) Al₂O₃ + Y₂O₃ + La₂O₃ +Gd₂O₃ (mol%) (3×Al2 O3 +Y2 O3 +La2 O3 +Gd2 O3 + BaO / 3+(CaO+SrO) / 6) (mol%) (3×Al2 O3 +Y2 O3 +La2 O3 +Gd2 O3 + BaO / 3+(CaO+SrO) / 6) / (P₂O₅ + Li₂O + CuO) O ions (oxides) Coefficient × Cation (mole) Example 61 0.00 69.67 1.09 0.00 28.63 1.66 14.53 0.209 309.87 Example 62 0.00 68.42 1.10 0.00 29.40 2.14 14.93 0.218 308.86 Example 63 0.00 72.02 3.91 2.63 24.97 2.97 16.37 0.227 317.91 Example 64 0.00 72.98 1.16 0.00 24.85 2.14 13.42 0.184 308.88 Example 65 0.00 68.85 1.20 0.80 27.69 3.47 18.03 0.262 309.34 Example 66 0.00 69.01 1.18 0.78 27.97 2.98 15.11 0.219 309.10

[0197] [Table 5-1] Transmittance @λT50 = 645nm Transmittance @λT50 = 633nm Example Comparative Example No. Plate thickness (mm) T1200 (%) Ave.T1100-800 (%) T750 (%) T600 (%) T400 (%) Plate thickness (mm) T1200 (%) Ave.T1100-800 (%) T750 (%) T600 (%) T400 (%) Example 1 0.170 2.420 0.386 4.049 75.895 85.936 0.225 0.751 0.071 1.483 71.402 84.147 Example 2 0.153 3.585 1.204 4.379 76.550 87.133 0.203 1.241 0.297 1.619 72.148 85.676 Example 3 0.151 3.304 0.637 4.417 76.165 86.742 0.200 1.130 0.134 1.660 71.725 85.187 Example 4 0.136 4.965 1.520 4.856 76.366 86.849 0.180 1.935 0.410 1.879 71.971 85.323 Example 5 0.138 4.423 0.915 4.817 76.262 86.684 0.182 1.673 0.216 1.873 71.874 85.121 Example 6 0.117 6.096 1.176 5.454 75.642 85.667 0.153 2.610 0.316 2.255 71.209 83.849 Example 7 0.120 6.150 1.639 5.209 76.483 86.596 0.159 2.578 0.459 2.071 72.136 85.002 Example 8 0.099 10.089 3.639 6.913 75.589 86.127 0.129 5.181 1.391 3.167 71.295 84.500 Example 9 0.105 9.073 3.852 6.382 75.878 86.330 0.137 4.449 1.474 2.808 71.568 84.728 Example 10 0.103 9.130 3.065 6.520 75.821 86.198 0.134 4.514 1.098 2.909 71.534 84.572 Example 11 0.093 10.940 3.725 7.342 75.600 86.153 0.121 5.795 1.447 3.452 71.352 84.550 Example 12 0.110 7.889 2.030 5.618 76.300 86.133 0.145 3.614 0.614 2.310 71.954 84.421 Example 13 0.103 8.303 2.000 5.850 75.822 86.018 0.135 3.940 0.624 2.490 71.467 84.314 Example 14 0.105 7.935 1.805 5.707 75.906 85.851 0.137 3.713 0.551 2.411 71.572 84.101 Example 15 0.110 7.829 2.111 5.651 75.926 86.081 0.145 3.644 0.673 2.377 71.591 84.393 Example 16 0.110 7.829 1.868 5.713 75.952 85.683 0.144 3.630 0.569 2.401 71.601 83.873 Example 17 0.109 7.545 2.461 5.570 76.229 85.959 0.143 3.427 0.798 2.299 71.896 84.208 Example 18 0.107 8.279 3.704 5.792 75.944 85.808 0.141 3.909 1.379 2.446 71.595 84.036 Example 19 0.111 7.955 2.039 5.741 75.769 85.493 0.145 3.730 0.641 2.433 71.409 83.644 Example 20 0.109 7.575 1.719 5.696 75.771 85.549 0.143 3.492 0.517 2.404 71.402 83.712 Example 21 0.111 7.517 2.820 5.485 76.196 86.037 0.146 3.417 0.967 2.258 71.865 84.313 Example 22 0.113 6.912 2.245 5.466 76.144 85.839 0.149 3.065 0.720 2.252 71.810 84.061 Example 23 0.136 6.235 1.524 4.997 76.331 86.869 0.180 2.616 0.418 1.952 71.928 85.350 Example 24 0.109 7.924 2.518 5.792 76.199 86.061 0.143 3.648 0.821 2.414 71.847 84.335 Example 25 0.166 5.967 1.064 4.555 76.384 86.422 0.220 2.453 0.263 1.715 71.964 84.758 Example 26 0.164 6.131 1.032 4.644 76.229 86.462 0.216 2.571 0.259 1.782 71.826 84.831 Example 27 0.178 5.716 0.962 4.490 76.476 87.041 0.237 2.297 0.227 1.667 72.040 85.550 Example 28 0.166 5.871 0.952 4.567 76.344 86.795 0.220 2.383 0.226 1.707 71.878 85.230 Example 29 0.147 5.614 1.100 4.346 76.437 85.384 0.194 2.269 0.272 1.616 72.043 83.418 Example 30 0.141 6.138 1.191 4.708 76.434 86.083 0.187 2.562 0.306 1.804 72.057 84.330

[0198] [Table 5-2] Transmittance @λT50 = 645nm Transmittance @λT50 = 633nm Example Comparative Example No. Plate thickness (mm) T1200 (%) Ave.T1100-800 (%) T750 (%) T600 (%) T400 (%) Plate thickness (mm) T1200 (%) Ave.T1100-800 (%) T750 (%) T600 (%) T400 (%) Example 31 0.115 9.231 2.024 5.862 76.000 85.046 0.150 4.511 0.637 2.486 71.667 83.059 Example 32 0.118 8.642 1.911 5.389 75.947 83.451 0.155 4.099 0.584 2.202 71.548 80.992 Example 33 0.136 5.811 1.076 4.490 76.070 83.894 0.179 2.427 0.275 1.729 71.692 81.553 Example 34 0.095 8.422 3.869 6.327 75.500 78.928 0.123 4.090 1.514 2.818 71.178 75.416 Example 35 0.136 6.639 1.539 5.002 76.248 86.637 0.179 2.873 0.429 1.978 71.879 85.068 Example 36 0.098 9.186 2.418 6.354 75.858 85.818 0.127 4.546 0.813 2.810 71.575 84.084 Example 37 0.097 9.903 4.813 6.222 76.007 85.574 0.127 4.987 1.962 2.715 71.725 83.758 Example 38 0.089 13.671 4.955 8.284 74.773 79.147 0.115 7.946 2.187 4.174 70.538 75.884 Example 39 0.081 9.477 4.339 7.011 75.279 76.917 0.106 4.820 1.770 3.260 70.972 72.983 Example 40 0.093 10.613 2.829 6.630 75.612 84.696 0.121 5.515 1.008 2.987 71.303 82.666 Example 41 0.084 12.120 3.114 7.023 75.307 83.566 0.110 6.612 1.165 3.254 70.984 81.262 Example 42 0.123 12.199 2.875 7.632 75.001 81.159 0.159 6.780 1.088 3.700 70.728 78.313 Example 43 0.179 11.035 2.416 6.870 75.418 83.778 0.233 5.861 0.844 3.167 71.128 81.535 Example 44 0.121 5.836 1.463 4.971 75.636 83.755 0.158 2.483 0.416 2.013 71.239 81.421 Example 45 0.162 12.775 2.829 7.269 75.394 85.975 0.209 7.126 1.050 3.431 71.138 84.337 Example 46 0.077 13.453 3.828 7.299 75.463 82.431 0.100 7.596 1.520 3.435 71.199 79.845 Example 47 0.129 18.122 4.807 8.623 74.666 82.277 0.166 11.384 2.126 4.379 70.385 79.748 Example 48 0.108 21.057 6.228 9.481 74.244 76.092 0.138 14.069 3.048 5.091 70.061 72.289 Example 49 0.103 22.85 6.562 9.845 74.25 82.32 0.132 15.563 3.278 5.313 70.039 79.896 Example 50 0.142 3.235 1.070 3.535 76.009 82.607 0.188 1.088 0.260 1.224 71.490 79.832 Example 51 0.148 20.133 5.334 8.706 74.637 82.687 0.190 13.131 2.466 4.484 70.420 80.300 Example 52 0.130 24.979 6.961 9.278 74.584 80.034 0.167 17.341 3.486 4.879 70.375 77.026 Example 53 0.083 10.259 6.783 75.366 85.528 0.108 5.336 2.408 3.119 71.071 83.757 Example 54 0.077 10.318 7.232 75.154 85.485 0.100 5.410 2.276 3.414 70.853 83.719 Example 55 0.067 11.519 7.812 74.967 85.190 0.087 6.304 4.105 3.819 70.694 83.375 Example 56 0.232 6.624 1.106 4.899 75.666 82.733 0.304 2.925 0.295 1.969 71.265 80.114 Example 57 0.271 4.010 0.540 3.549 76.269 81.762 0.359 1.441 0.108 1.225 71.798 78.739 Example 58 0.315 2.547 0.268 2.575 76.479 79.774 0.421 0.766 0.041 0.777 71.951 76.121 Example 59 0.136 7.005 1.547 5.102 76.193 86.207 0.179 3.076 0.432 2.024 71.797 84.506 Example 60 0.123 9.383 2.532 5.946 76.147 86.607 0.162 4.617 0.847 2.539 71.859 85.069 Compare X 0.352 1.846 0.156 2.059 73.631 69.056 0.463 0.538 0.023 0.621 68.694 63.135 Compare A 0.125 5.963 2.057 4.579 76.344 81.915 0.166 2.459 0.610 1.733 71.929 78.960 Compare B 0.091 7.714 4.856 5.651 75.965 83.367 0.119 3.561 1.965 2.368 71.619 80.912 Compare C 0.147 5.181 0.938 4.201 76.536 85.249 0.196 2.010 0.217 1.521 72.100 83.212 Compare D 0.089 36.027 13.809 13.887 72.114 87.082 0.111 28.827 8.950 8.852 68.090 86.005

[0199] [Table 5-3] Transmittance @λT50 = 645nm Transmittance @λT50 = 633nm Example Comparative Example No. Plate thickness (mm) T1200 (%) Ave.T1100-800 (%) T750 (%) T600 (%) T400 (%) Plate thickness (mm) T1200 (%) Ave.T1100-800 (%) T750 (%) T600 (%) T400 (%) Example 61 0.160 9.22 1.689 5.851 75.040 86.070 0.209 4.578 0.536 2.527 70.664 84.520 Example 62 0.165 11.38 2.359 6.472 74.730 86.550 0.214 6.136 0.837 2.950 70.410 85.180 Example 63 0.160 8.30 1.562 5.826 74.868 86.022 0.210 4.009 0.482 2.527 70.485 84.474 Example 64 0.120 11.00 2.498 6.542 74.889 86.311 0.156 5.850 0.879 2.977 70.580 84.867 Example 65 0.119 13.52 2.865 7.513 74.388 83.546 0.154 7.806 1.158 3.662 70.124 81.432 Example 66 0.127 12.87 2.981 7.126 74.576 85.270 0.164 7.230 1.159 3.363 70.256 83.564

[0200] [Table 6-1] Transmittance @ plate thickness 0.11mm Transmittance @ plate thickness 0.21mm Example Comparative Example No. λT50 (nm) T1200 (%) Ave.T1100-800 (%) T750 (%) T600 (%) T400 (%) λT50 (nm) T1200 (%) Ave.T1100-800 (%) T750 (%) T600 (%) T400 (%) Example 1 666 8.785 2.590 12.245 81.175 87.953 636 1.041 0.113 1.963 72.627 84.642 Example 2 660 8.882 4.008 10.259 80.528 88.400 632 1.063 0.243 1.400 71.526 85.465 Example 3 660 8.168 2.414 10.090 80.124 88.077 631 0.906 0.097 1.356 70.842 84.870 Example 4 655 8.624 3.285 8.471 79.065 87.755 627 1.005 0.165 0.971 69.066 84.279 Example 5 655 8.150 2.287 8.725 79.157 87.681 627 0.902 0.087 1.028 69.219 84.143 Example 6 648 7.112 1.496 6.403 76.476 86.001 620 0.696 0.042 0.569 64.812 81.093 Example 7 649 7.775 2.313 6.682 77.700 87.031 622 0.825 0.088 0.618 66.807 82.956 Example 8 640 7.953 2.581 5.232 74.028 85.543 614 0.861 0.107 0.387 60.908 80.269 Example 9 643 8.149 3.332 5.639 75.212 86.087 616 0.902 0.176 0.447 62.782 81.246 Example 10 642 7.788 2.429 5.434 74.831 85.828 615 0.827 0.094 0.416 62.176 80.780 Example 11 637 7.494 2.120 4.685 73.042 85.195 611 0.769 0.074 0.314 59.369 79.648 Example 12 645 7.939 2.049 5.659 76.336 86.147 619 0.858 0.069 0.450 64.586 81.356 Example 13 642 7.045 1.546 4.846 74.839 85.639 616 0.683 0.042 0.334 62.190 80.442 Example 14 643 7.046 1.498 4.987 75.210 85.575 616 0.683 0.041 0.353 62.780 80.326 Example 15 645 7.910 2.144 5.717 75.986 86.104 618 0.852 0.079 0.459 64.022 81.277 Example 16 645 7.830 1.868 5.715 75.953 85.683 618 0.836 0.061 0.458 63.969 80.521 Example 17 644 7.310 2.352 5.376 76.051 85.888 618 0.733 0.090 0.408 64.126 80.889 Example 18 644 7.823 3.437 5.427 75.607 85.673 617 0.834 0.184 0.415 63.413 80.503 Example 19 645 8.056 2.078 5.823 75.844 85.524 618 0.882 0.073 0.475 63.793 80.235 Example 20 645 7.466 1.681 5.605 75.687 85.514 618 0.763 0.051 0.442 63.541 80.218 Example 21 645 7.672 2.900 5.613 76.311 86.082 619 0.804 0.140 0.443 64.546 81.238 Example 22 646 7.439 2.490 5.922 76.549 86.001 619 0.758 0.105 0.490 64.930 81.093 Example 23 655 10.451 3.312 8.739 79.076 87.785 627 1.450 0.175 1.031 69.083 84.333 Example 24 644 7.661 2.397 5.575 76.004 85.985 618 0.802 0.094 0.437 64.050 81.063 Example 25 665 15.063 4.679 12.600 81.277 88.190 635 2.914 0.344 2.073 72.800 85.078 Example 26 664 14.883 4.347 12.347 81.002 88.159 634 2.848 0.304 1.994 72.331 85.021 Example 27 668 16.528 5.335 14.240 81.991 88.812 638 3.480 0.437 2.618 74.027 86.226 Example 28 664 14.767 4.266 12.497 81.200 88.425 635 2.806 0.293 2.040 72.668 85.512 Example 29 658 11.294 3.272 9.321 80.009 86.933 630 1.682 0.172 1.166 70.648 82.778 Example 30 657 11.167 3.056 9.084 79.586 87.305 628 1.646 0.155 1.110 69.936 83.455

[0201] [Table 6-2] Transmittance @ plate thickness 0.11mm Transmittance @ plate thickness 0.21mm Example Comparative Example No. λT50 (nm) T1200 (%) Ave.T1100-800 (%) T750 (%) T600 (%) T400 (%) λT50 (nm) T1200 (%) Ave.T1100-800 (%) T750 (%) T600 (%) T400 (%) Example 31 647 10.114 2.348 6.539 76.571 85.303 620 1.362 0.095 0.593 64.966 79.840 Example 32 648 10.083 2.447 6.485 76.890 83.969 621 1.355 0.103 0.583 65.483 77.474 Example 33 655 9.893 2.495 8.034 78.869 85.354 627 1.306 0.106 0.878 68.738 79.931 Example 34 638 5.725 2.341 4.106 73.159 77.032 612 0.460 0.093 0.244 59.551 65.714 Example 35 655 10.915 3.305 8.676 78.966 87.581 627 1.576 0.173 1.017 68.900 83.961 Example 36 639 6.865 1.538 4.532 74.054 85.095 614 0.650 0.042 0.294 60.950 79.469 Example 37 639 7.293 3.223 4.298 74.066 84.760 613 0.730 0.163 0.266 60.969 78.872 Example 38 635 8.768 2.535 4.727 71.289 76.466 608 1.037 0.107 0.319 56.679 64.796 Example 39 631 4.267 1.507 2.839 70.222 72.295 606 0.262 0.040 0.121 55.070 58.216 Example 40 637 7.065 1.488 4.039 72.903 83.428 611 0.687 0.040 0.236 59.155 76.524 Example 41 633 6.534 1.142 3.205 70.902 81.217 607 0.592 0.026 0.152 56.093 72.699 Example 42 650 15.078 4.098 9.910 76.605 82.211 621 2.920 0.277 1.310 65.021 74.406 Example 43 671 24.969 9.615 18.661 81.337 86.764 637 7.649 1.312 4.387 72.903 82.472 Example 44 649 7.453 2.101 6.439 76.943 84.435 621 0.761 0.074 0.575 65.570 78.296 Example 45 665 23.974 8.407 16.332 80.271 87.777 633 7.078 1.038 3.401 71.090 84.318 Example 46 629 5.874 1.006 2.448 69.361 78.709 604 0.483 0.020 0.091 53.789 68.472 Example 47 653 23.071 7.382 12.262 76.991 83.622 623 6.577 0.826 1.968 65.648 76.863 Example 48 644 20.512 5.944 9.106 73.965 75.838 615 5.255 0.555 1.115 60.810 63.784 Example 49 642 20.83 5.541 8.481 73.21 81.73 613 5.409 0.519 0.974 59.636 73.579 Example 50 657 6.896 2.888 7.386 79.315 84.591 629 0.656 0.135 0.748 69.482 78.574 Example 51 661 29.812 10.965 16.017 78.732 84.942 629 10.730 1.721 3.277 68.511 79.197 Example 52 654 30.593 10.283 13.259 77.030 81.755 623 11.272 1.569 2.285 65.712 73.621 Example 53 632 5.085 2.266 2.944 70.763 83.627 607 0.367 0.087 0.129 55.884 76.872 Example 54 629 4.013 1.552 2.412 68.947 82.914 604 0.233 0.043 0.088 53.177 75.626 Example 55 623 3.110 1.839 1.651 65.996 81.297 599 0.143 0.061 0.043 48.917 72.834 Example 56 684 26.390 10.936 22.873 83.736 87.356 650 8.502 1.664 6.470 77.063 83.549 Example 57 691 25.700 10.959 24.455 85.107 87.547 656 8.082 1.659 7.351 79.489 83.898 Example 58 697 26.282 11.455 26.383 86.102 87.378 663 8.435 1.801 8.497 81.274 83.589 Example 59 655 11.415 3.320 8.830 78.928 87.232 627 1.717 0.176 1.051 68.837 83.322 Example 60 650 11.996 3.707 7.984 77.691 87.147 623 1.887 0.215 0.867 66.792 83.167 Compare X 702 27.042 11.822 27.977 85.646 83.945 668 8.907 1.916 9.504 80.453 77.430 Compare A 651 8.277 3.230 6.560 78.045 83.036 624 0.929 0.162 0.596 67.374 75.838 Compare B 636 4.609 2.656 3.165 73.041 81.723 611 0.304 0.114 0.148 59.369 73.566 Compare C 658 10.745 2.941 9.189 80.140 86.853 630 1.529 0.143 1.134 70.868 82.633 Compare D 633 29.002 9.056 8.961 68.196 86.034 603 10.180 1.289 1.081 52.078 81.152

[0202] [Table 6-3] Transmittance @ plate thickness 0.11mm Transmittance @ plate thickness 0.21mm Example Comparative Example No. λT50 (nm) T1200 (%) Ave.T1100-800 (%) T750 (%) T600 (%) T400 (%) λT50 (nm) T1200 (%) Ave.T1100-800 (%) T750 (%) T600 (%) T400 (%) Example 61 664.089 18.966 5.650 13.883 79.818 87.687 632.89 4.544 0.530 2.504 70.618 84.504 Example 62 666.119 22.795 7.758 15.647 79.897 88.114 633.85 6.455 0.911 3.147 70.753 85.292 Example 63 664.102 17.594 5.392 13.794 79.676 87.650 632.74 3.937 0.468 2.474 70.379 84.435 Example 64 649.438 13.229 3.396 8.227 76.193 86.736 620.60 2.284 0.191 0.922 64.622 82.762 Example 65 649.115 15.695 3.671 9.129 75.588 84.128 619.58 3.166 0.269 1.125 63.646 78.077 Example 66 652.109 16.642 4.559 9.955 76.583 86.040 622.36 3.540 0.366 1.327 65.255 81.500

[0203] [Table 7-1] Transmittance @ plate thickness 0.23mm Transmittance @ plate thickness 0.25mm DSC Example Comparative Example No. λT50 (nm) T1200 (%) T600 (%) T400 (%) λT50 (nm) T1200 (%) T600 (%) T400 (%) Tg (°C) Tm (°C) Weather resistance Example 1 632 0.680 71.029 83.995 629 0.444 69.465 83.353 308 790 B Example 2 628 0.695 69.850 84.889 625 0.455 68.214 84.318 314 812 B Example 3 627 0.584 69.119 84.243 624 0.376 67.438 83.620 316 806 B Example 4 623 0.654 67.223 83.600 620 0.425 65.429 82.927 318 817 B Example 5 624 0.581 67.386 83.453 621 0.374 65.602 82.768 327 812 B Example 6 617 0.437 62.702 80.145 614 0.274 60.661 79.208 327 816 A Example 7 619 0.527 64.819 82.164 616 0.336 62.890 81.380 325 823 A Example 8 610 0.552 58.578 79.254 608 0.354 56.337 78.252 357 828 B Example 9 613 0.581 60.555 80.311 610 0.374 58.406 79.387 342 821 B Example 10 612 0.528 59.915 79.807 609 0.337 57.736 78.846 352 825 B Example 11 608 0.488 56.959 78.582 605 0.309 54.646 77.531 364 842 B Example 12 615 0.550 62.463 80.430 612 0.352 60.409 79.515 341 809 B Example 13 612 0.428 59.929 79.441 609 0.269 57.750 78.452 329 818 B Example 14 613 0.429 60.552 79.316 610 0.269 58.403 78.318 334 816 B Example 15 615 0.546 61.865 80.344 612 0.350 59.782 79.423 334 822 B Example 16 615 0.534 61.809 79.526 612 0.342 59.722 78.544 328 817 B Example 17 615 0.463 61.975 79.925 612 0.292 59.897 78.972 332 815 A Example 18 614 0.533 61.221 79.507 611 0.341 59.105 78.524 333 817 A Example 19 615 0.567 61.623 79.217 612 0.364 59.527 78.212 335 816 A Example 20 614 0.484 61.356 79.199 611 0.306 59.247 78.193 334 823 A Example 21 615 0.512 62.420 80.303 613 0.326 60.364 79.378 342 814 A Example 22 616 0.480 62.827 80.145 613 0.304 60.792 79.209 333 822 A Example 23 623 0.977 67.242 83.660 620 0.658 65.449 82.991 B Example 24 615 0.510 61.895 80.113 612 0.325 59.812 79.174 342 817 A Example 25 631 2.098 71.214 84.469 628 1.511 69.663 83.864 343 756 A Example 26 632 2.067 71.655 84.908 628 1.487 70.131 84.338 341 768 A Example 27 634 2.548 72.530 85.718 631 1.866 71.063 85.213 316 751 B Example 28 631 2.013 71.073 84.941 628 1.444 69.512 84.374 316 757 B Example 29 626 1.149 68.912 81.971 623 0.785 67.218 81.172 B Example 30 625 1.122 68.151 82.706 622 0.765 66.412 81.963 B

[0204] [Table 7-2] Transmittance @ plate thickness 0.23mm Transmittance @ plate thickness 0.25mm DSC Example Comparative Example No. λT50 (nm) T1200 (%) T600 (%) T400 (%) λT50 (nm) T1200 (%) T600 (%) T400 (%) Tg (°C) Tm (°C) Weather resistance Example 31 616 0.912 62.865 78.790 613 0.611 60.832 77.754 352 856 B Example 32 617 0.907 63.414 76.237 614 0.607 61.409 75.019 361 794 B Example 33 623 0.871 66.874 78.888 620 0.581 65.060 77.859 355 789 A Example 34 609 0.278 57.150 63.659 606 0.168 54.845 61.667 373 840 B Example 35 623 1.070 67.047 83.255 620 0.727 65.243 82.555 B Example 36 610 0.406 58.622 78.390 607 0.253 56.383 77.325 344 823 B Example 37 610 0.461 58.642 77.745 607 0.291 56.404 76.633 341 828 B Example 38 605 0.677 54.138 62.685 602 0.442 51.711 60.643 408 820 S Example 39 603 0.150 52.457 55.748 600 0.086 49.968 53.384 383 839 B Example 40 608 0.431 56.733 75.213 605 0.270 54.411 73.925 356 819 B Example 41 604 0.366 53.525 71.106 601 0.226 51.075 69.547 364 818 B Example 42 617 2.103 62.924 72.936 614 1.514 60.894 71.496 401 798 S Example 43 633 6.037 71.324 81.639 630 4.765 69.779 80.815 393 835 S Example 44 618 0.482 63.505 77.123 615 0.305 61.506 75.967 348 752 A Example 45 629 5.545 69.384 83.643 625 4.345 67.719 82.973 393 824 S Example 46 601 0.293 51.122 66.591 598 0.178 48.587 64.761 367 807 B Example 47 619 5.117 63.589 75.578 616 3.981 61.594 74.315 S Example 48 611 4.002 58.474 61.614 608 3.048 56.228 59.517 392 794 S Example 49 609 4.131 57.239 72.049 606 3.155 54.938 70.550 391 803 S Example 50 625 0.410 67.667 77.422 622 0.256 65.899 76.288 332 704 B Example 51 625 8.746 66.632 78.095 621 7.130 64.804 77.009 B Example 52 619 9.232 63.656 72.094 616 7.561 61.665 70.599 370 785 B Example 53 604 0.217 53.307 75.588 601 0.128 50.849 74.326 359 848 B Example 54 601 0.132 50.486 74.247 598 0.075 47.930 72.894 360 860 B Example 55 596 0.078 46.073 71.251 593 0.042 43.395 69.701 377 873 B Example 56 645 6.778 75.794 82.808 641 5.404 74.545 82.073 348 752 S Example 57 652 6.412 78.411 83.187 648 5.088 77.348 82.481 326 833 B Example 58 659 6.720 80.341 82.851 655 5.354 79.419 82.120 307 656 B Example 59 623 1.175 66.979 82.561 620 0.805 65.172 81.808 C Example 60 619 1.304 64.803 82.393 616 0.901 62.873 81.626 324 796 D Compare X 664 7.133 79.453 76.190 660 5.712 78.466 74.969 273 690 E Compare A 620 0.600 65.422 74.475 617 0.387 63.526 73.137 E Compare B 608 0.176 56.958 72.035 605 0.102 54.645 70.536 E Compare C 627 1.036 69.147 81.813 624 0.701 67.467 81.002 319 751 E Compare D 599 8.257 49.343 80.209 596 6.697 46.753 79.278 374 733 S

[0205] [Table 7-3] Transmittance @ plate thickness 0.23mm Transmittance @ plate thickness 0.25mm DSC Example Comparative Example No. λT50 (nm) T1200 (%) T600 (%) T400 (%) λT50 (nm) T1200 (%) T600 (%) T400 (%) Tg (°C) Tm (°C) Weather resistance Example 61 629 3.416 68.940 83.897 625 2.565 67.237 83.261 435 S Example 62 630 5.013 69.031 84.727 626 3.892 67.333 84.156 440 S Example 63 629 2.918 68.652 83.806 625 2.161 66.931 83.162 420 S Example 64 617 1.608 62.531 81.992 614 1.131 60.471 81.208 440 S Example 65 616 2.299 61.508 76.927 613 1.668 59.396 75.770 450 S Example 66 619 2.600 63.233 80.640 615 1.906 61.209 79.753 456 S

[0206] As shown in the table above, the glasses of Examples 1 to 66 can be confirmed to still have high transmittance in the visible light region (purple to red region) and excellent near-infrared cutoff capability, and suppress the reduction of weather resistance, even when the glass is made thinner. Regarding the relevant weather resistance, comparing Examples 1-58 with Example 59, the value calculated by "(3×Al2O3 +Y2O3 +La2O3 +Gd2O3 +BaO / 3+(CaO+SrO) / 6)" is 0 for Example 59, while Examples 1-58, which have a larger value, are confirmed to have better weather resistance. Comparing the relevant Examples 59 and 60, the value calculated from "(3×Al2O3 +Y2O3 +La2O3 +Gd2O3 +BaO / 3+ (CaO+SrO) / 6)" is 0, and the value of "(Na2O+K2O+ZnO) / Li2O" exceeds 1.4. Example 60 is larger than Example 59, indicating that Example 60 has a greater degree of deliquescence than Example 59, and is slightly worse in terms of weather resistance. Comparative Example X has a value of over 0 calculated from "(3×Al2O3 +Y2O3 +La2O3 +Gd2O3 +BaO / 3+(CaO+SrO) / 6)," but the value of "(Na2O+K2O+ZnO) / Li2O" is a relatively large value of over 11, indicating low weather resistance. Comparative Examples A, B, and C are glasses composed of only three components: P₂O₅, Li₂O, and CuO, and have extremely low weather resistance. The comparative example D series O / P ratio exceeds 3.2, making it impossible to obtain the required transmittance characteristics.

[0207] In the aforementioned embodiments where weather resistance evaluation is differentiated into S or A based on visual inspection, related embodiments 25, 33, 56, and 61-66 also utilize a haze meter to obtain haze values. The obtained haze values ​​are shown in Table 8.

[0208] [Table 8] Weather resistance (Visual evaluation) Turbidity value O / P ratio (3×Al₂O₃ +Y₂O₃ +La₂O₃ + Gd₂O₃ + BaO / 3 + (CaO + SrO) / 6) (mol%) (MgO+CaO+SrO+BaO+ZnO) / (Li₂O + Na₂O + K₂O) Example 25 A 43.2% 2.93 8.55 0.73 Example 33 A 34.9% 2.93 4.52 1.47 Example 56 S 0.0% 3.01 12.93 0.22 Example 61 S 13.0% 3.00 14.53 26.38 Example 62 S 8.0% 3.02 14.93 26.64 Example 63 S 1.0% 3.00 16.37 5.72 Example 64 S 10.0% 3.02 13.42 21.45 Example 65 S 0.5% 3.06 18.03 22.36 Example 66 S 0.4% 3.04 15.11 23.00

[0209] As shown in Table 8, compared to Examples 25 and 33, which were rated A in the weather resistance evaluation by visual inspection, Examples 56, 61-66, which were rated S in the weather resistance evaluation by visual inspection, had lower haze values, below 15%.

[0210] The results above confirm that, in order to achieve both improved transmittance in the visible light domain and improved near-infrared cutoff capability, the haze value should be set below 15%, the O / P ratio should be in the range of 3.00 to 3.15, and the value (in moles) calculated by "(3×Al2O3 +Y2O3 +La2O3 +Gd2O3 +BaO / 3+(CaO+SrO) / 6)" should be in the range of 10.0% to 40.0%.

[0211] Finally, summarize all the aforementioned states and conditions.

[0212] According to the sample, the glass 1 to 6 described above can be provided.

[0213] In the first form, in glass 1~6, the Al2O3 content can be set to less than 2.0 moles.

[0214] In the first form of glass (1-6), the total content of Al2O3, La2O3, Y2O3 and Gd2O3 (Al2O3 + La2O3 + Y2O3 + Gd2O3) can be set to 0.1 moles or more.

[0215] In one form, glass series 1 to 6 can have the following transmittance characteristics.

[0216] For wavelengths above 550nm, the external transmittance, including reflection loss, is 50%, and the glass thickness is less than 0.25mm for wavelengths of 633nm. Of the aforementioned thicknesses, the external transmittance T600, including reflection loss, reaches over 50% at a wavelength of 600nm, and the external transmittance T1200, including reflection loss, is below 30% at a wavelength of 1200nm.

[0217] For wavelengths above 550nm, the external transmittance, including reflection loss, is 50%, and the glass thickness is less than 0.25mm for wavelengths of 633nm. At the aforementioned thicknesses, the external transmittance T600, including reflection loss, reaches over 50% at a wavelength of 600nm, and the external transmittance T1200, including reflection loss, is below β1% at a wavelength of 1200nm. β1 is derived from the following formula B1: (Formula B1) β1=64×R-170 The calculated value; In equation B1 above, The above ratio (O ions / P ions) is used for the R series.

[0218] The transmittance characteristics of a thickness of 0.11mm are converted. The external transmittance, including reflection loss, is 50% in the wavelength half-value λT 50 series in the range of 600nm~650nm. When the wavelength is 1200nm, the external transmittance, including reflection loss, is less than 30% in the T1200 series. And when the wavelength is 400nm, the external transmittance, including reflection loss, is more than 70% in the T400 series.

[0219] The transmittance characteristics of a thickness of 0.21mm are converted. The external transmittance, including reflection loss, is 50% in the wavelength half-value λT 50 series in the range of 600nm~650nm. When the wavelength is 1200nm, the external transmittance, including reflection loss, is less than 25% in the T1200 series. And when the wavelength is 400nm, the external transmittance, including reflection loss, is more than 70% in the T400 series.

[0220] For wavelengths above 550 nm, the external transmittance, including reflection loss, is 50%, and the glass thickness is less than 0.25 mm for a wavelength of 645 nm. Of the aforementioned thicknesses, the external transmittance, including reflection loss, is greater than 50% for the T600 series at a wavelength of 600nm, and less than 30% for the T1200 series at a wavelength of 1200nm.

[0221] For wavelengths above 550 nm, the external transmittance, including reflection loss, is 50%, and the glass thickness is less than 0.25 mm for a wavelength of 645 nm. For the aforementioned thicknesses, the external transmittance (including reflection loss) of the T600 series at a wavelength of 600 nm is greater than 50%, and the external transmittance (including reflection loss) of the T1200 series at a wavelength of 1200 nm is less than β1%. The above β1 is derived from the following formula B1: (Formula B1) β1=64×R-170 The calculated value; In equation B1 above, The above ratio (O ions / P ions) is used for the R series.

[0222] According to a sample, a near-infrared cutoff filter made of the aforementioned near-infrared absorbing glass can be provided.

[0223] The embodiments disclosed herein are merely illustrative and should not be considered limiting. The scope of this invention is not limited to what has been described above, but rather encompasses all modifications within the same meaning and scope as indicated in the claims. For example, by adjusting the composition as described in the specification for the glass composition exemplified above, a near-infrared absorbing glass similar to that of the present invention can be obtained. Furthermore, any combination of two or more items can be made, as exemplified or described in the instruction manual or the preferred scope.

[0224] none.

Claims

1. A near-infrared absorbing glass, comprising four or more major cations selected from the group consisting of: P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, and Y ions; P ions, Li ions, and Cu ions are essential cations; the anion group contains at least O ions; the ratio of O ion content to P ion content (O ions / P ions) is 3.10 or less; in the glass composition expressed as anion%, the O ion content is 90.0% or more; in the oxide-based glass composition, based on molar standards, the total oxide content of the above-mentioned major cations is 90.0% or more; the total content of MgO and Al2O3 (MgO+Al2O3) is 8.0% or less, the V2O5 content is 1.0% or less, and the Al2O3 content is 3.5% or less; The ratio of Na2O, K2O, and ZnO content to Li2O content ((Na2O+K2O+ZnO) / Li2O) is less than 2.4; the ratio of B2O3 and SiO2 content (B2O3+SiO2) is less than 3.0%; the CuO content is greater than α1%; α1 is the value calculated by the following formula 1: (Formula 1) α1=70400×exp(-2.855×R); In Formula 1 above, R is the above ratio (O ions / P ions). Converted to the transmittance characteristics of a thickness of 0.21mm, the external transmittance T1200, including reflection loss, is less than 10% at a wavelength of 1200nm, and the external transmittance T400, including reflection loss, is greater than 70% at a wavelength of 400nm.

2. A near-infrared absorbing glass, wherein, The glass composition contains at least four major cations selected from the group consisting of: P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, and Y ions; P ions, Li ions, and Cu ions are essential cations; the anion system contains at least O ions; the ratio of O ion content to P ion content (O ions / P ions) is 3.10 or less; in the glass composition expressed as anion%, the O ion content is 90.0% or more; in the oxide-based glass composition, based on molar standards, the total oxide content of the above major cations is 90.0% or more; the total content of MgO and Al2O3 (MgO+Al2O3) is 8.0% or less, the V2O5 content is 1.0% or less, and the Al2O3 content is 3.5% or less; The ratio of Na2O, K2O, and ZnO content relative to Li2O content ((Na2O+K2O+ZnO) / Li2O) is less than 2.4; the ratio of B2O3 and SiO2 content (B2O3+SiO2) is less than 3.0%; and the following formula 2 is satisfied: (Formula 2) C-3200×exp(-2.278×R)≧0 In the above formula 2, C is the CuO content per mole volume of the glass (unit: millimole / cc); R is the above ratio (O ions / P ions). Converting the transmittance characteristics of a thickness of 0.21mm, the external transmittance T1200, including reflection loss, is less than 10% at a wavelength of 1200nm, and the external transmittance T400, including reflection loss, is more than 70% at a wavelength of 400nm.

3. A near-infrared absorbing glass, comprising four or more major cations selected from the group consisting of P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, Y ions, B ions, and Si ions; P ions, Li ions, and Cu ions are essential cations; the anion group contains at least O ions; the ratio of O ion content to P ion content (O ions / P ions) is 3.10 or less; in the glass composition expressed as anion%, the O ion content is 90.0% or more; in the oxide-based glass composition, based on molar standards, the total oxide content of the above-mentioned major cations is 90.0% or more; the total content of MgO and Al2O3 (MgO+Al2O3) is 8.0% or less, the V2O5 content is 1.0% or less, and the Al2O3 content is 3.5% or less; The ratio of the total content of Na2O, K2O and ZnO ((Na2O+K2O+ZnO) / Li2O) relative to the Li2O content is 2.4 or less; the A1 calculated by Equation 3: (Equation 3) A1={O(P)-O(others)}×Cu is 2500 or more; in Equation 3 above, O(P) represents the amount of oxygen constituting P-ion oxides in the oxide-based glass composition; O(others) represents the amount of oxygen of the oxides constituting the above-mentioned main cations in the oxide-based glass composition minus the amount of oxygen of the above-mentioned O(P); Cu represents the CuO content in the oxide-based glass composition in molar terms. The transmittance characteristics converted to a thickness of 0.21 mm are as follows: the external transmittance T1200, including reflection loss, is 10% or less at a wavelength of 1200 nm, and the external transmittance T400, including reflection loss, is 70% or more at a wavelength of 400 nm.

4. A near-infrared absorbing glass, comprising four or more major cations selected from the group consisting of P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, Y ions, B ions, and Si ions; P ions, Li ions, and Cu ions are essential cations; the anion group contains at least O ions; the ratio of O ion content to P ion content (O ions / P ions) is 3.10 or less; in the glass composition expressed as anion%, the O ion content is 90.0% or more; in the oxide-based glass composition, based on molar standards, the total oxide content of the above-mentioned major cations is 90.0% or more; the total content of MgO and Al2O3 (MgO+Al2O3) is 8.0% or less, the V2O5 content is 1.0% or less, and the Al2O3 content is 3.5% or less; The ratio of the total content of Na2O, K2O and ZnO ((Na2O+K2O+ZnO) / Li2O) relative to the Li2O content is 2.4 or less; the A2 calculated by Equation 4: (Equation 4) A2={O(P)-O(others)}×C is 700 or more; in Equation 4 above, C is the CuO content per mole volume of the glass (unit: millimoles / cc); O(P) represents the amount of oxygen constituting P-ion oxides in the glass composition based on oxides; O(others) represents the amount of oxygen of the above-mentioned O(P) deducted from the amount of oxygen constituting the above-mentioned main cations in the glass composition based on oxides. Converting the transmittance characteristics of a thickness of 0.21mm, the external transmittance T1200, including reflection loss, is 10% or less at a wavelength of 1200nm, and the external transmittance T400, including reflection loss, is 70% or more at a wavelength of 400nm.

5. A near-infrared absorbing glass, comprising four or more major cations selected from the group consisting of: P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, and Y ions; P ions, Li ions, and Cu ions are essential cations; the anion group contains at least O ions; the ratio of O ion content to P ion content (O ions / P ions) is 3.10 or less; in the glass composition expressed as anion%, the O ion content is 90.0% or more; in the oxide-based glass composition, based on molar standards, the total oxide content of the above-mentioned major cations is 90.0% or more; the total content of MgO and Al2O3 (MgO+Al2O3) is 8.0% or less, the V2O5 content is 1.0% or less, and the Al2O3 content is 3.5% or less; The ratio of Na2O, K2O, and ZnO content to Li2O content ((Na2O+K2O+ZnO) / Li2O) is less than 2.4; the CuO content is greater than α2%; α2 is the value calculated by the following formula 5: (Formula 5) α2=(76522)×exp(-2.855×R); In the above formula 5, R is the above ratio (O ions / P ions). Converted to the transmittance characteristics of a thickness of 0.21mm, the external transmittance T1200, including reflection loss, is less than 10% at a wavelength of 1200nm, and the external transmittance T400, including reflection loss, is greater than 70% at a wavelength of 400nm.

6. A near-infrared absorbing glass, comprising four or more major cations selected from the group consisting of: P ions, Li ions, Cu ions, Al ions, Ba ions, Sr ions, Ca ions, Mg ions, Zn ions, K ions, Na ions, La ions, Gd ions, and Y ions; P ions, Li ions, and Cu ions are essential cations; the anion group contains at least O ions; the ratio of O ion content to P ion content (O ions / P ions) is 3.10 or less; in the glass composition expressed as anion%, the O ion content is 90.0% or more; in the glass composition based on oxides, the total oxide content of the above-mentioned major cations is 90.0% or more on a molar basis; the total content of MgO and Al2O3 (MgO+Al2O3) is 8.0% or less, the V2O5 content is 1.0% or less, and the Al2O3 content is 3.5% or less; The ratio of the total content of Na2O, K2O and ZnO relative to the Li2O content ((Na2O+K2O+ZnO) / Li2O) is less than 2.4; satisfying the following formula 6: (Formula 6) C-(3478)×exp(-2.278×R)≧0 In the above formula 6, C is the CuO content per mole volume of the glass (unit: millimole / cc); R is the above ratio (O ions / P ions). Converting the transmittance characteristics of a thickness of 0.21mm, the external transmittance including reflection loss T1200 is less than 10% at a wavelength of 1200nm, and the external transmittance including reflection loss T400 is more than 70% at a wavelength of 400nm.

7. The near-infrared absorbing glass as described in any of claims 1 to 6, wherein, The combined content of Na2O and K2O is less than 15.0 mol.

8. The near-infrared absorbing glass as described in any of claims 1 to 6, wherein, The Al2O3 content was less than 2.0 moles.

9. The near-infrared absorbing glass as described in any of claims 1 to 6, wherein, The total content of Al2O3, La2O3, Y2O3 and Gd2O3 (Al2O3+La2O3+Y2O3+Gd2O3) is above 0.1 mol%.

10. The near-infrared absorbing glass as described in any of claims 1 to 6, wherein, For wavelengths above 550 nm, the half-value λT50, which makes the external transmittance, including reflection loss, 50%, is 633 nm, and the glass thickness is 0.25 mm or less. Among the above thicknesses, the external transmittance T600, including reflection loss, is 50% or more at a wavelength of 600 nm, and the external transmittance T1200, including reflection loss, is 30% or less at a wavelength of 1200 nm.

11. The near-infrared absorbing glass as described in any of claims 1 to 6, wherein, For wavelengths above 550 nm, the half-value λT50, which makes the external transmittance, including reflection loss, 50%, is 633 nm, and the glass thickness is 0.25 mm or less. Among the above thicknesses, the external transmittance T600, including reflection loss, is 50% or more at a wavelength of 600 nm, and the external transmittance T1200, including reflection loss, is β1% or less at a wavelength of 1200 nm. β1 is the value calculated by the following formula B1: (Formula B1) β1 = 64 × R - 170. In the above formula B1, R is the above ratio (O ions / P ions).

12. The near-infrared absorbing glass as described in any of claims 1 to 6, wherein, The transmittance characteristics of a thickness of 0.11 mm are calculated as follows: the half-value of the wavelength λT50, which includes reflection loss, is 50% in the range of 600 nm to 650 nm; the external transmittance T1200, which includes reflection loss, is less than 30% at a wavelength of 1200 nm; and the external transmittance T400, which includes reflection loss, is more than 70% at a wavelength of 400 nm.

13. The near-infrared absorbing glass as described in any of claims 1 to 6, wherein, The transmittance characteristics of a thickness of 0.21 mm are calculated, and the half-value of the wavelength λT50, which includes the external transmittance loss of 50%, is in the range of 600 nm to 650 nm.

14. The near-infrared absorbing glass as described in any of claims 1 to 6, wherein, For wavelengths above 550nm, the half-value λT50, which makes the external transmittance, including reflection loss, 50%, is 645nm, and the glass thickness is 0.25mm or less. Among the above thicknesses, the external transmittance T600, including reflection loss, is 50% or more at a wavelength of 600nm, and the external transmittance T1200, including reflection loss, is 30% or less at a wavelength of 1200nm.

15. The near-infrared absorbing glass as described in any of claims 1 to 6, wherein, For wavelengths above 550 nm, the half-value λT50, which makes the external transmittance, including reflection loss, 50%, is 645 nm, and the glass thickness is 0.25 mm or less. Among the above thicknesses, the external transmittance T600, including reflection loss, is 50% or more at a wavelength of 600 nm, and the external transmittance T1200, including reflection loss, is β1% or less at a wavelength of 1200 nm. The above β1 is the value calculated by the following formula B1: (Formula B1) β1=64×R-170. In the above formula B1, R is the above ratio (O ions / P ions).

16. The near-infrared absorbing glass as described in any of claims 1 to 6, wherein, The V2O5 content is below 0.1%.

17. A near-infrared cutoff filter, comprising the near-infrared absorbing glass of any one of claims 1 to 16.

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