Silicate and borosilicate glasses having high refractive index and low density

Abstract

Provided are glasses containing silicon dioxide (Si02) and / or boron oxide (B203) as glass formers and having a refractive index n greater than or equal to 1.9 d (at 587.56 nm) and a density (measured at 25 °C) less than or equal to 5.5 g / cm 3 Optionally, the glasses can be characterized by high transmission in the visible and near-ultraviolet (near-UV) range of the electromagnetic spectrum and / or good glass forming ability.

Description

[0001] This application claims priority to U.S. Provisional Patent Application Serial No. 63 / 076,547, filed September 10, 2020, pursuant to 35 USC §119(e), the entire contents of which are incorporated herein by reference. Technical Field

[0002] This disclosure generally relates to silica-borate and borosilicate glasses with high refractive index and low density. Background Technology

[0003] Glass is used in a variety of optical devices, including augmented reality devices, virtual reality devices, mixed reality devices, and eyeglasses. The properties required for this type of glass typically include a high refractive index and low density. Other desired properties may include high transmittance and / or low optical dispersion in the visible and near-ultraviolet (near-UV) ranges of the electromagnetic spectrum. Demanding a combination of these desired properties and the ability to form a glass from a composition with good glass-forming ability can be challenging. For example, generally, as the refractive index of glass increases, its density tends to increase as well. Substances such as TiO2 and Nb2O5 are often added to increase the refractive index of the glass without increasing its density. However, these materials typically absorb blue and UV light, which undesirably reduces the light transmittance of the glass in this spectral region. Generally, attempting to increase the refractive index of glass while maintaining low density without reducing transmittance in the blue and UV regions of the spectrum results in a decrease in the glass-forming ability of the material. For example, crystallization and / or liquid-liquid phase separation can occur during the cooling of the glass melt at industrially acceptable cooling rates. Typically, as the amount of certain substances (e.g., ZrO2, Y2O3, Sc2O3, BeO, etc.) increases, the glass forming ability appears to decrease.

[0004] Depending on the glass-forming agent used, low-density, high-refractive-index glasses typically fall into one of two chemical systems: (a) borosilicate or borosilicate glasses, where SiO2 and / or B2O3 are used as the primary glass-forming agent, and (b) phosphate glasses, where P2O5 is used as the primary glass-forming agent. The use of glasses that rely on other oxides as primary glass-forming agents (GeO2, TeO2, Bi2O3, and V2O5) can be challenging due to cost, glass-forming capability, optical properties, and / or production requirements.

[0005] Phosphate glasses can be characterized by high refractive index and low density; however, their production is challenging due to the risk of P2O5 volatilization from the melt and / or incompatibility with platinum. Furthermore, phosphate glasses are typically highly colored and may require additional bleaching steps to provide glass with the desired transmission properties. In addition, phosphate glasses exhibiting high refractive indices tend to have increased optical dispersion.

[0006] Generally speaking, borosilicate and borosilicate glasses are easier to manufacture and can exhibit high transmittance without a bleaching step. However, compared to phosphate glasses, borosilicate and borosilicate glasses typically exhibit increased density with increasing refractive index.

[0007] Based on these considerations, there is a demand for borosilicate and borosilicate glasses with high refractive index and low density, optionally combined with high transmittance in the visible and near-UV ranges and / or made from compositions that provide good glass-forming capabilities. Summary of the Invention

[0008] According to embodiments of this disclosure, the glass comprises: SiO2 of 14.0 mol% to 50.0 mol%, B2O3 greater than 0.0 mol%, TiO2 of 5.0 mol% to 40.0 mol%, Nb2O5 of 2.2 mol% to 50.0 mol%, ZrO2 of 2.5 mol% to 25.0 mol%, and the total content of rare earth metal oxides (RE) m O n The content of B₂O₃ is 0.0 mol% to 30.0 mol%, and other oxides (if present, at 0.5 mol% or less). The ratio of the amount of B₂O₃ to the amount of SiO₂ (B₂O₃ / SiO₂) is at least 0.050 in mol% of oxides. In addition, the glass is essentially free of Y₂O₃.

[0009] According to another embodiment of this disclosure, the glass comprises: B2O3 of 1.0 mol to 40.0 mol%, La2O3 of 13.5 mol% or more, SiO2 of ≥0.0 mol%, wherein the sum of (SiO2 + B2O3) is 1.0 mol to 50.0 mol%, and at least one oxide selected from: rare earth metal oxides, Al2O3, Nb2O5, TiO2, ThO2, GeO2, P2O5, ZnO, Y2O3, BaO, Bi2O3, CaO, Er2O3, Gd2O3, K2O The glass contains La₂O₃, Li₂O, Na₂O, Nd₂O₃, PbO, TeO₂, WO₃, Yb₂O₃, and ZrO₂, with the following prerequisites: Nb₂O₅ from 0.0 mol to 12.3 mol%; TiO₂ from 0.0 mol to 33.0 mol%; ThO₂ from 0.0 mol to 5.0 mol%; GeO₂ from 0.0 mol to 10.0 mol%; P₂O₅ from 0.0 mol to 20.0 mol%; Al₂O₃ from 0.0 mol to 2.5 mol%; and the sum of (ZnO + Y₂O₃) from 0.0 mol to 2.5 mol%. The glass also satisfies the following equation (X):

[0010] P n –(0.815+0.25*P d )>0.000(X)

[0011] In the formula, P n It is the refractive index parameter of the glass and is calculated according to the following equation (VIII):

[0012]

[0013] as well as

[0014] P d It is a density parameter and is calculated according to the following equation (IX):

[0015]

[0016] Furthermore, each oxide listed in equations (VIII) and (IX) refers to the amount of oxide in the glass, expressed in moles.

[0017] According to another embodiment, the glass comprises: 14.5 mol% or more of B2O3, 2.0 mol% or more of SiO2, wherein the sum of (SiO2 + B2O3) is 3.0 mol% to 50.0 mol%, Nb2O5 is 1.0 mol% to 45.0 mol%, and at least one oxide selected from: monovalent metal oxides, divalent metal oxides, rare earth metal oxides, As2O3, Sb2O3, Al2O3, TiO2, MoO3, Ta2O5, GeO2, P2O5, ZnO, Y2O3, BaO, Bi2O3, CaO, Er2O3, Gd2O3, Ga2O3, K2O, La2O3, Li2O, Na2O, Nd2O3, PbO, TeO2, WO3, Yb2O3, and ZrO2, provided that: TiO2 is 0.0 mol% to 36 mol%. 0.0 mol%; ZrO2 is 0.0 mol% or more; Y2O3 is 0.0 mol% to 1.0 mol%; Ta2O5 is 0.0 mol% to 1.5 mol%; GeO2 is 0.0 mol% to 0.5 mol%; CaO is 0.0 mol% to 15.0 mol%; P2O5 is 0.0 mol% to 20.0 mol%; Al2O3 is 0.0 mol% to 2.5 mol%; ZnO is 0.0 mol% to 5.5 mol%; MoO3 from 0.0 mol% to 3.0 mol%; MgO from 0.0 mol% to 15.0 mol%; Ga2O3 from 0.0 mol% to 5.0 mol%; Li2O from 0.0 mol% to 8.0 mol%; TeO2 from 0.0 mol% to 10.0 mol%; total content of monovalent metal oxides (R2O) from 0.0 mol% to 15.0 mol%; total content of rare earth metal oxides (RE) m O n The content of (As₂O₃ + Sb₂O₃) ranges from 0.0 mol% to 50.0 mol%; the sum of (As₂O₃ + Sb₂O₃) ranges from 0.0 mol% to 1.0 mol%; (RE) m O n The sum of (TiO2+Nb2O5+ZrO2+Bi2O3+WO3) is 25.0 mol% or greater; and the sum of (R2O+RO–BaO) is 0.0 mol% to 20.0 mol%, where RO is the total content of divalent metal oxides. The glass is also essentially free of fluorine. Furthermore, the glass satisfies the following equation (XII):

[0018] P n –(0.815+0.25*P d )–(0.16–0.38*T i >0.000(XII)

[0019] In the formula, P nIt is the refractive index parameter, with a value of 1.85 or greater, and is calculated according to the following equation (VIII):

[0020]

[0021] In the formula, P d The density parameter is calculated based on the following equation (IX):

[0022]

[0023] as well as

[0024] In the formula, T i The transmittance index is calculated based on the following equation (VI):

[0025]

[0026] Furthermore, each oxide listed in equations (VIII), (IX), and (VI) refers to the amount of oxide in the glass, expressed in moles.

[0027] Those skilled in the art will understand and appreciate these and other aspects, objects and features of this disclosure by studying the following description, claims and drawings. Attached Figure Description

[0028] In the attached diagram:

[0029] Figure 1 The density d at room temperature is shown for some comparative glass and some exemplary glass according to embodiments of this disclosure. RT The density parameter P calculated according to equation (IX) d Relationship diagram;

[0030] Figure 2 The refractive index n of some comparative glass and some exemplary glass according to embodiments of this disclosure is shown. d (Measured at 587.56 nm) and the refractive index parameter P calculated according to equation (VIII) n Relationship diagram;

[0031] Figure 3 These are exemplary cooling scheme diagrams of some exemplary glasses according to "15-minute test" conditions and "2.5-minute test" conditions, implemented according to embodiments of this disclosure;

[0032] Figure 4 The density parameter P, calculated according to Equation (IX), is shown for some comparative glass and some exemplary glass according to embodiments of this disclosure. d The refractive index parameter P calculated according to equation (VIII)n Relationship diagram;

[0033] Figure 5 The density d at room temperature is shown for some comparative glass and some exemplary glass according to embodiments of this disclosure. RT (Unit: g / cm³) 3 ) and refractive index n d Relationship diagram between (measured at 587.56 nm);

[0034] Figure 6 The transmittance index T, calculated according to Equation (VI), is shown for some comparative glass and some exemplary glass according to embodiments of this disclosure. i The refractive index parameter P calculated according to equation (VIII) n The density parameter P calculated according to equation (IX) d Relationship diagram; and

[0035] Figure 7 The transmittance index T, calculated according to Equation (VI), is shown for some comparative glass and some exemplary glass according to embodiments of this disclosure. i Refractive index n d (Measured at 587.56 nm) and density d at room temperature RT A diagram showing the relationships between them. Detailed Implementation

[0036] In the following detailed description, exemplary embodiments illustrating specific details are given for illustrative purposes and not for limitation, in order to provide a full understanding of the various principles of this disclosure. However, it will be apparent to those skilled in the art that this disclosure may be practiced in other ways than those detailed herein, after benefiting from this specification. Furthermore, descriptions of well-known devices, methods, and materials may have been omitted so as not to obscure the description of the various principles of the invention. Finally, wherever applicable, the same reference numerals denote the same elements.

[0037] As used herein, the term "and / or" when used to list two or more items means that any one of the listed items may be used alone, or any combination of two or more of the listed items may be used. For example, if a composition is described as containing components A, B, and / or C, the composition may contain only A; only B; only C; a combination of A and B; a combination of A and C; a combination of B and C; or a combination of A, B, and C.

[0038] Those skilled in the art, as well as those who utilize and use this disclosure, will make improvements to it. Therefore, it is to be understood that the embodiments shown in the accompanying drawings and described above are merely illustrative and not intended to limit the scope of this disclosure, which is defined by the appended claims and, in accordance with the principles of patent law, is to include the doctrine of equivalents.

[0039] As used herein, the term "about" indicates that a quantity, size, formulation, parameter, and other variable and characteristic is not, and does not need to be, exact, but may be approximate and / or larger or smaller as required, reflecting tolerances, conversion factors, rounding and measurement errors, and other factors known to those skilled in the art. When the term "about" is used to describe a value or endpoint of a range, it should be understood that this disclosure includes the specific value or endpoint referenced. Whether or not the endpoints of a numerical value or range in this specification are stated as "about," the endpoints are intended to include both implementations: one modified with "about" and one not modified with "about." It will also be understood that each endpoint value of a range is meaningful both in relation to and unrelated to another endpoint value.

[0040] The term “formed from…” can indicate one or more of the following: including, substantially composed of, or composed of. For example, a component formed from a particular material may include, substantially composed of, or be composed of that particular material.

[0041] Unless otherwise stated, all compositions are expressed as mole percentages (mol%) of the ingredients. Those skilled in the art will understand that various melt components (e.g., fluorine, alkali metals, boron, etc.) may undergo different levels of volatility during melting (e.g., as a function of vapor pressure, melting time, and / or melting temperature). Therefore, the term "about" in relation to such components is intended to include values ​​that, when measured in the final article, differ from the composition of the ingredients provided herein by within about 0.2 mol%. In view of the foregoing, substantial compositional equivalence between the final article and the ingredient composition is anticipated. In some embodiments, when indicated, the composition may be expressed as a percentage of the ingredients by weight (wt%) of the oxides.

[0042] When fluorine is added to or present in an oxide glass, the molecular representation of the resulting glass composition can be expressed in different ways. In this disclosure, the fluorine content (when present) as a single item is expressed as an atomic percentage (atomic %), which is determined by multiplying the fraction of fluorine in the sum of all atoms in the glass composition by a factor of 100.

[0043] In this disclosure, the following method is used to represent fluorine-containing compositions and concentration ranges. The concentration limits for all oxides presented (e.g., SiO2, B2O3, Na2O, etc.) are based on the following assumptions: the corresponding cations (e.g., silicon [SiO2], B2O3, Na2O, etc.) are based on the following assumptions: 4+ Boron [B] 3+ ], sodium [Na + The oxygen atoms in the oxides are initially present as the corresponding oxides. When fluorine is present, for the purpose of calculating the component concentration of the composition, a portion of the oxygen atoms in the oxides is equivalently replaced with fluorine (i.e., one oxygen atom is replaced by two fluorine atoms). It is assumed that the fluorine is present in the form of silicon fluoride (SiF4); therefore, the sum of all oxides and SiF4 is assumed to be 100 mol% or 100 wt% in all compositions.

[0044] In this document, the terms “free from” and “substantially free from” are used interchangeably, referring to the absence of an amount of a particular component in the glass composition that has not been intentionally added to the glass composition and / or the absence of that particular component. It should be understood that the glass composition may contain trace amounts of a particular constituent component as a contaminant or in an indefinite amount of less than 0.10 mol%.

[0045] As used herein, when describing a particular constituent component in a glass composition, the term "uncertain" refers to a constituent component that is not intentionally added to the glass composition and is present in an amount of less than 0.05 mol%. Uncertain components may be unintentionally added to the glass composition as impurities in another constituent component and / or through migration of uncertain components into the composition during the processing of the glass composition.

[0046] The term “glass forming agent” is used herein to refer to a component that, when present alone in a glass composition (i.e., in the absence of other components, except in indefinite amounts), is capable of forming glass when the melt is cooled at a rate not exceeding about 200°C / min to about 300°C / min.

[0047] As used herein, the term "modifier" refers to an oxide of a monovalent or divalent metal, namely M₂O or MO, where "M" represents a metal. Modifiers can be added to glass compositions to alter the atomic structure of the melt and the resulting glass. In some embodiments, the modifier can alter the coordination number of cations present in the glass forming agent (e.g., boron in B₂O₃), which can lead to the formation of a more polymeric atomic network and, as a result, provide better glass forming.

[0048] As used herein, the term "RO" refers to the total content of divalent metal oxides, the term "R2O" refers to the total content of monovalent metal oxides, and the term "Alk2O" refers to the total content of alkali metal oxides. The term R2O encompasses alkali metal oxides (Alk2O) as well as other monovalent metal oxides, such as Ag2O, Tl2O, and Hg2O. As discussed below, in this disclosure, rare earth metal oxides are expressed with their standard formula (RE2O3), wherein the rare earth metal oxide has a redox state of "+3", and therefore are not included in the term RO.

[0049] As used herein, the term "rare earth metal" refers to the metals listed in the lanthanide series of the IUPAC periodic table, plus yttrium and scandium. As used herein, the term "rare earth metal oxide" is used to describe oxides of rare earth metals in different redox states, such as "+3" for lanthanum in La₂O₃, "+4" for cerium in CeO₂, and "+2" for europium in EuO, etc. Generally, the redox state of rare earth metals in oxide glasses can be altered, and specifically, the redox state may change during melting, depending on the batch composition and / or the redox conditions in the furnace where the glass is melted and / or heat-treated (e.g., annealed). Unless otherwise stated, rare earth metal oxides herein are expressed in their standard form, where the rare earth metal oxide has a redox state of "+3". Therefore, when a rare earth metal with a redox state other than "+3" is added to a glass composition batch, the glass composition is recalculated by adding or subtracting some oxygen to maintain the stoichiometry. For example, when CeO2 (cerium in the "+4" redox state) is used as a batch component, the resulting glass composition is recalculated as if 2 moles of CeO2 were equivalent to 1 mole of Ce2O3, and the resulting glass composition exhibits Ce2O3. As used herein, the term "RE" refers to... m O n "RE2O3" is used to refer to the total content of rare earth metal oxides in all redox states, and the term "RE2O3" is used to refer to the total content of rare earth metal oxides in the "+3" redox state.

[0050] The density values ​​of the glass recorded in this article are obtained using measurements with an error of 0.001 g / cm³. 3 The specific gravity of the helium flask was measured at room temperature, and the unit is g / cm³. 3 As used in this paper, density measurements at room temperature (defined as d) RTThis refers to measurements taken at 20°C or 25°C, and includes measurements obtained at temperatures ranging from 20°C to 25°C. It should be understood that room temperature may vary between about 20°C and about 25°C; however, for the purposes of this disclosure, density changes within the temperature range of 20°C to 25°C are expected to be less than 0.001 g / cm³. 3 The error is negligible and therefore is not expected to affect the room temperature density measurements recorded in this paper.

[0051] Unless otherwise stated, as used herein, the term "low density" means a density less than or equal to 5.5 g / cm³. 3 The term "low density parameter" refers to the density parameter P. d The value is less than or equal to 5.5 g / cm³. 3 .

[0052] As used herein, good glass-forming ability refers to the melt's resistance to devitrification as the material cools. Glass-forming ability can be measured by determining the critical cooling rate of the melt. As used herein, the term "critical cooling rate" or "v" refers to the glass's resistance to devitrification. cr The critical cooling rate refers to the minimum cooling rate at which a melt of a given composition can form glass without visually visible crystals under an optical microscope at magnification of 100x to 500x. The critical cooling rate can be used to measure the glass-forming ability of a composition, that is, the ability of a melt of a given glass composition to form glass upon cooling. Generally speaking, the lower the critical cooling rate, the better the glass-forming ability.

[0053] The term "liquidline temperature" in this document refers to the temperature above which the glass composition is completely liquid and free of crystallization of glass constituent components. The liquidline temperature values ​​recorded herein are obtained by means of DSC or by isothermal holding of the sample wrapped in platinum foil. For samples measured using DSC, the powdered sample was heated to 1250°C at a rate of 10 K / min. The endpoint corresponding to the endothermic event of crystal melting is considered the liquidline temperature. For the second technique (isothermal holding), a glass block (approximately 1 cm²) was used. 3 The glass was wrapped in platinum foil (to prevent evaporation) and placed in a furnace at a given temperature for 17 hours. The glass block was then examined using an optical microscope to inspect the crystals.

[0054] Unless otherwise stated, the refractive index values ​​recorded herein were measured at room temperature (approximately 25°C). The refractive index values ​​of the glass samples were measured using a Metricon Model 2010 prism-coupled refractometer with an error of approximately ±0.0002. Using the Metricon, the refractive index of the glass samples was measured at two or more wavelengths, approximately 406 nm, 473 nm, 532 nm, 633 nm, 828 nm, and 1064 nm. The measured correlations characterized the dispersion, which was then fitted using either Cauchy's law equation or the Sellmeier equation to calculate the refractive index of the sample at a given wavelength of interest between the measurement wavelengths. In this document, the term "refractive index n" is used. d "Refractive index n" refers to the refractive index calculated at a wavelength of 587.56 nm as described above, which corresponds to the wavelength of the helium d-line. As used herein, the term "refractive index n" is... C "Refractive index n" refers to the refractive index calculated at a wavelength of 656.3 nm as described above. In this document, the term "refractive index n" is used... F "Refractive index n" refers to the refractive index calculated at a wavelength of 486.1 nm as described above. In this document, the term "refractive index n" is used... g "Refers to the refractive index calculated at a wavelength of 435.8 nm, as mentioned above."

[0055] Unless otherwise stated, as used herein, the term "high refractive index" or "high refractive index" refers to a glass refractive index value greater than or equal to at least 1.85, measured at a wavelength of 587.56 nm. In the cases shown, the term "high refractive index" or "high refractive index" refers to a glass refractive index value greater than or equal to at least 1.85, greater than or equal to 1.90, greater than or equal to 1.95, or greater than or equal to 2.00, measured at a wavelength of 587.56 nm. As used herein, the term "high refractive index parameter" refers to a refractive index parameter P greater than or equal to 1.85, greater than or equal to at least 1.90, greater than or equal to 1.95, or greater than or equal to 2.00. n .

[0056] Unless otherwise stated, as used herein, the term "internal transmittance" refers to the transmittance through a glass sample after adjusting for Fresnel loss. The term "transmittance" is used to describe a transmittance value without considering Fresnel loss. For 2 mm thick samples, the transmittance of the glass samples was measured using a Cary 5000 spectrometer (1 nm resolution, integrating sphere) at wavelengths from 250 nm to 2500 nm. The internal transmittance value of a 10 mm thick sample was calculated between 375 nm and 1175 nm using the measured refractive index and the measured raw transmittance.

[0057] As used herein, the term "blue light" refers to light corresponding to wavelengths from approximately 330 nm to approximately 480 nm. The term "internal transmittance of blue light" refers to the transmittance of blue light after adjusting for Fresnel loss. The term "transmittance of blue light" refers to the transmittance of blue light without taking Fresnel loss into account.

[0058] Embodiments of this disclosure generally relate to silica-borate and borosilicate glasses having high refractive indices and low densities. In some embodiments, the glass may also be characterized by high transmittance in the visible and near-ultraviolet (near-UV) ranges of the electromagnetic spectrum. The glasses of this disclosure may contain silica (SiO2) and boron oxide (B2O3) as glass-forming agents, and one or more additional modifiers and / or refractive index enhancers, examples of which include oxides of divalent and monovalent metals, ZrO2, La2O3, Nb2O5, TiO2, and Gd2O3. In some embodiments, the glass may contain a lower content of TiO2 and a higher content of La2O3, ZrO2, and / or other low-absorption oxide materials.

[0059] According to embodiments of this disclosure, the glass described herein comprises silicon dioxide (SiO2) and / or boron oxide (B2O3) as glass-forming agents. Increasing the amount of the glass-forming oxides (e.g., SiO2 and B2O3) results in a corresponding increase in viscosity at a given temperature, which protects the melt from crystallization during cooling and thus provides a glass with a lower critical cooling rate. In some embodiments, the glass of this disclosure may contain both SiO2 and B2O3 to provide a glass with a desired critical cooling rate, i.e., a desired degree of glass-forming ability.

[0060] According to some embodiments, the amount of silicon dioxide (SiO2) contained in the glass composition can be greater than or equal to 0.0 mol% to less than or equal to 50.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of SiO2 contained in the glass composition can be greater than or equal to 0.0 mol%, greater than or equal to 2.0 mol%, greater than or equal to 4.0 mol%, greater than or equal to 6.0 mol%, greater than or equal to 10.0 mol%, greater than or equal to 12.0 mol%, greater than or equal to 14.0 mol%, greater than or equal to 20.0 mol%, greater than or equal to 30.0 mol%, greater than or equal to 40.0 mol%, greater than or equal to 44.0 mol%, greater than or equal to 46.0 mol%, or greater than or equal to 48.0 mol%. In some other embodiments, the amount of SiO2 contained in the glass composition may be: less than or equal to 50.0 mol%, less than or equal to 48.0 mol%, less than or equal to 46.0 mol%, less than or equal to 44.0 mol%, less than or equal to 40.0 mol%, less than or equal to 30.0 mol%, less than or equal to 20.0 mol%, less than or equal to 10.0 mol%, less than or equal to 6.0 mol%, less than or equal to 4.0 mol%, or less than or equal to 2.0 mol%.In some further embodiments, the amount of SiO2 contained in the glass composition may be: 0.0 mol% to 50.0 mol%, 0.0 mol% to 44.0 mol%, 0.0 mol% to 20.0 mol%, 2.0 mol% to 50.0 mol%, 2.0 mol% to 20.0 mol%, 4.0 mol% to 50.0 mol%, 4.0 mol% to 20.0 mol%, 6.0 mol% to 46.0 mol%, 6.0 mol% to 40.0 mol%, 10.0 mol% to 20.0 mol%, 14.0 mol% to 50.0 mol%, 14.0 mol% to 45.0 mol%, 14.0 mol% to 40.0 mol%, 14.0 mol% to 36.0 mol%, 14.0 mol% to 35.0 mol%, 14.0 mol% to 30.0 mol%, and 30.0 mol% to 48.0 mol%. %, 30.0 mol% to 46.0 mol%, 30.0 mol% to 44.0 mol%, 30.0 mol% to 40.0 mol%, 20.0 mol% to 50.0 mol%, 20.0 mol% to 45.0 mol%, 20.0 mol% to 40.0 mol%, 20.0 mol% to 35.0 mol%, 20.0 mol% to 30.0 mol%, 25.0 mol% to 50.0 mol%, 25.0 mol% to 45.0 mol%, 25.0 mol% to 40.0 mol%, 25.0 mol% to 35.0 mol%, 25.0 mol% to 30.0 mol%, 2.0 mol% to 36.0 mol%, 12.0 mol% to 36.0 mol%, 8.0 mol% to 25.0 mol%, 21.0 mol% to 42.0 mol%, or 10.0 mol% to 32.0 mol%.

[0061] According to some embodiments, the amount of boron oxide (B₂O₃) contained in the glass composition can be greater than or equal to 0.0 mol% to less than or equal to 51.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of B₂O₃ contained in the glass composition can be greater than or equal to 0.0 mol%, greater than or equal to 1.0 mol%, greater than or equal to 2.0 mol%, greater than or equal to 4.0 mol%, greater than or equal to 6.0 mol%, greater than or equal to 10.0 mol%, greater than or equal to 14.0 mol%, greater than or equal to 14.5 mol%, greater than or equal to 17.0 mol%, greater than or equal to 20.0 mol%, greater than or equal to 30.0 mol%, greater than or equal to 40.0 mol%, or greater than or equal to 50.0 mol%. In some other embodiments, the amount of B2O3 contained in the glass composition may be: less than or equal to 51.0 mol%, less than or equal to 50.0 mol%, less than or equal to 40.0 mol%, less than or equal to 30.0 mol%, less than or equal to 20.0 mol%, less than or equal to 10.0 mol%, less than or equal to 6.0 mol%, less than or equal to 4.0 mol%, or less than or equal to 2.0 mol%. In some further embodiments, the amount of B2O3 contained in the glass composition may be: 0.0 mol% to 51.0 mol%, 14.5 mol% to 51.0 mol%, 0.0 mol% to 30.0 mol%, 14.5 mol% to 30.0 mol%, 1.0 mol% to 40.0 mol%, 2.0 mol% to 40.0 mol%, 4.0 mol% to 40.0 mol%, 14.5 mol% to 40.0 mol%, 6.0 mol% to 51.0 mol%, 6.0 mol% to 40.0 mol%, 6.0 mol% to 20.0 mol%, 10.0 mol% to 50.0 mol%, 10.0 mol% to 40.0 mol%, 10.0 mol% to 30.0 mol%. %, 10.0 mol% to 20.0 mol%, 14.5 mol% to 50.0 mol%, 14.5 mol% to 40.0 mol%, 14.5 mol% to 30.0 mol%, 14.5 mol% to 20.0 mol%, 20.0 mol% to 51.0 mol%, 20.0 mol% to 50.0 mol%, 20.0 mol% to 40.0 mol%, 20.0 mol% to 30.0 mol%, 30.0 mol% to 50.0 mol%, 14.0 mol% to 48.0 mol%, 30.0 mol% to 40.0 mol%, 3.0 mol% to 30.0 mol%, 15.0 mol% to 32.0 mol%, or 13.0 mol% to 38.0 mol%.

[0062] However, the combination of SiO2 and B2O3 can lead to a decrease in refractive index, which may make it more challenging to provide glass with the desired high refractive index. Therefore, in some embodiments, the total amount of SiO2 and B2O3 (SiO2 + B2O3) in the glass can be limited. In some embodiments, the sum of (SiO2 + B2O3) contained in the glass composition can be greater than or equal to 0.0 mol% to less than or equal to 50.0 mol%, and all ranges and subranges between the above values. In some embodiments, the sum of (SiO2 + B2O3) contained in the glass composition may be in the following amounts: greater than or equal to 0.0 mol%, greater than or equal to 1.0 mol%, greater than or equal to 2.0 mol%, greater than or equal to 3.0 mol%, greater than or equal to 4.0 mol%, greater than or equal to 6.0 mol%, greater than or equal to 10.0 mol%, greater than or equal to 20.0 mol%, greater than or equal to 30.0 mol%, greater than or equal to 40.0 mol%, greater than or equal to 44.0 mol%, greater than or equal to 46.0 mol%, or greater than or equal to 48.0 mol%. In some other embodiments, the sum of (SiO2 + B2O3) contained in the glass composition may be in amounts of: less than or equal to 50.0 mol%, less than or equal to 48.0 mol%, less than or equal to 46.0 mol%, less than or equal to 44.0 mol%, less than or equal to 40.0 mol%, less than or equal to 30.0 mol%, less than or equal to 20.0 mol%, less than or equal to 10.0 mol%, less than or equal to 6.0 mol%, less than or equal to 4.0 mol%, or less than or equal to 2.0 mol%.In some further embodiments, the amount of (SiO2+B2O3) contained in the glass composition may be: 0.0 mol% to 50.0 mol%, 0.0 mol% to 44.0 mol%, 2.0 mol% to 44.0 mol%, 0.0 mol% to 20.0 mol%, 2.0 mol% to 20.0 mol%, 4.0 mol% to 44.0 mol%, 4.0 mol% to 20.0 mol%, 6.0 mol% to 50.0 mol%, 1.0 mol% to 50.0 mol%, 6.0 mol% to 46.0 mol%, 6.0 mol% to 40.0 mol%, 6.0 mol% to 20.0 mol%, 10.0 mol% to 46.0 mol%, 10.0 mol% to 40.0 mol%, 10. 0 mol% to 20.0 mol%, 20.0 mol% to 50.0 mol%, 30.0 mol% to 50.0 mol%, 20.0 mol% to 46.0 mol%, 20.0 mol% to 40.0 mol%, 30.0 mol% to 48.0 mol%, 30.0 mol% to 46.0 mol%, 30.0 mol% to 40.0 mol%, 30.0 mol% to 40.0 mol%, 25.0 mol% to 46.0 mol%, 7.0 mol% to 45.0 mol%, 24.0 mol% to 40.0 mol%, 17.0 mol% to 42.0 mol%, 9.0 mol% to 33.0 mol%, 3.0 mol% to 50.0 mol%, or 3.0 mol% to 44.0 mol%.

[0063] In some embodiments, the ratio of the amount of B2O3 to the amount of SiO2 in the glass composition (B2O3 / SiO2), based on the mole percent of oxides, can be at least 0.050. For example, the ratio (B2O3 / SiO2), based on the mole percent of oxides, is: at least 0.050, at least 0.10, at least 0.9, at least 1.1, at least 1.5, at least 1.7, at least 2.0, at least 2.5, at least 3.0, at least 3.5, at least 4.0, at least 4.5, at least 5.5, at least 6, at least 10, at least 100, or at least 1000.

[0064] In some embodiments, the amount of phosphorus oxide (P2O5) contained in the glass composition can be greater than or equal to 0.0 mol% to less than or equal to 20.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of P2O5 contained in the glass composition can be: greater than or equal to 0.0 mol%, greater than or equal to 1.0 mol%, greater than or equal to 2.0 mol%, greater than or equal to 3.0 mol%, greater than or equal to 5.0 mol%, greater than or equal to 10.0 mol%, greater than or equal to 15.0 mol%, greater than or equal to 17.0 mol%, greater than or equal to 18.0 mol%, or greater than or equal to 19.0 mol%. In some other embodiments, the amount of P2O5 contained in the glass composition may be: less than or equal to 20.0 mol%, less than or equal to 19.0 mol%, less than or equal to 18.0 mol%, less than or equal to 17.0 mol%, less than or equal to 15.0 mol%, less than or equal to 10.0 mol%, less than or equal to 5.0 mol%, less than or equal to 3.0 mol%, less than or equal to 2.0 mol%, or less than or equal to 1.0 mol%. In some further embodiments, the amount of P2O5 contained in the glass composition may be: 0.0 mol% to 20.0 mol%, 0.0 mol% to 17.0 mol%, 0.0 mol% to 5.0 mol%, 1.0 mol% to 17.0 mol%, 1.0 mol% to 5.0 mol%, 2.0 mol% to 18.0 mol%, 2.0 mol% to 15.0 mol%, 3.0 mol% to 18.0 mol%, 5.0 mol% to 18.0 mol%, 5.0 mol% to 15.0 mol%, 10.0 mol% to 20.0 mol%, 10.0 mol% to 18.0 mol%, 10.0 mol% to 17.0 mol%, 10.0 mol% to 15.0 mol%, 15.0 mol% to 19.0 mol%, 9.0 mol% to 16.0 mol%, 3.0 mol% to 10.0 mol%, or 1.0 mol% to 8.0 mol%.

[0065] According to embodiments of this disclosure, the glass may contain one or more refractive index enhancers added to increase the refractive index of the glass. Examples of refractive index enhancers that can be used in the glass of this disclosure include titanium oxide (TiO2), niobium oxide (Nb2O5), zirconium oxide (ZrO2), and other rare earth metal oxides.

[0066] Titanium oxide (TiO2) is generally expected to increase the refractive index of glass, combined with achieving low density and / or acceptable low dispersion. In some cases, titanium oxide may produce yellow or brown glass, which can be addressed by bleaching, for example by melting and / or annealing in the oxide state and / or by adding one or more oxidizing agents to the glass batch, examples of which include CeO2, As2O5, and Mn2O3. In some cases, too high a amount of titanium oxide can result in refractory materials (e.g., rutile (TiO2), sphene (CaTiSiO5)) and titanium niobate (e.g., Ti2Nb). 10 O 29 The crystallization of titanium dioxide (TID) can lead to an increase in the liquidus temperature of the glass, and thus potentially reduce the glass-forming ability of the melt. Furthermore, at high concentrations, TID can cause liquid-liquid phase separation in the melt, which can result in a loss of glass transmittance.

[0067] In some embodiments, the amount of titanium dioxide (TiO2) contained in the glass composition can be greater than or equal to 0.0 mol% to less than or equal to 55.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of TiO2 contained in the glass composition can be: greater than or equal to 0.0 mol%, greater than or equal to 2.0 mol%, greater than or equal to 4.0 mol%, greater than or equal to 5.0 mol%, greater than or equal to 6.0 mol%, greater than or equal to 7.0 mol%, greater than or equal to 10.0 mol%, greater than or equal to 13.0 mol%, greater than or equal to 20.0 mol%, greater than or equal to 30.0 mol%, greater than or equal to 40.0 mol%, greater than or equal to 50.0 mol%, greater than or equal to 52.0 mol%, or greater than or equal to 54.0 mol%. In some other embodiments, the amount of TiO2 contained in the glass composition may be: less than or equal to 55.0 mol%, less than or equal to 54.0 mol%, less than or equal to 52.0 mol%, less than or equal to 50.0 mol%, less than or equal to 40.0 mol%, less than or equal to 33.0 mol%, less than or equal to 30.0 mol%, less than or equal to 20.0 mol%, less than or equal to 10.0 mol%, less than or equal to 6.0 mol%, less than or equal to 4.0 mol%, or less than or equal to 2.0 mol%.In some further embodiments, the amount of TiO2 contained in the glass composition may be: 0.0 mol% to 55.0 mol%, 0.0 mol% to 50.0 mol%, 0.0 mol% to 36.0 mol%, 0.0 mol% to 35.0 mol%, 0.0 mol% to 33.0 mol%, 0.0 mol% to 20.0 mol%, 0.3 mol% to 35.0 mol%, 0.3 mol% to 33.0 mol%, 2.0 mol% to 50.0 mol%, 2.0 mol% to 33.0 mol%, 2.0 mol% to 20.0 mol%, 4.0 mol% to 50.0 mol%, 4.0 mol% to 33.0 mol%, 5.0 mol% to 40.0 mol%, 6.0 mol% to 40.0 mol%, 6.0 mol% to 33.0 mol%, 6. 0 mol% to 20.0 mol%, 10.0 mol% to 40.0 mol%, 10.0 mol% to 33.0 mol%, 12.0 mol% to 40.0 mol%, 12.0 mol% to 33.0 mol%, 20.0 mol% to 52.0 mol%, 20.0 mol% to 40.0 mol%, 20.0 mol% to 33.0 mol%, 30.0 mol% to 54.0 mol%, 30.0 mol% to 50.0 mol%, 30.0 mol% to 40.0 mol%, 40.0 mol% to 54.0 mol%, 40.0 mol% to 52.0 mol%, 40.0 mol% to 50.0 mol%, 24.0 mol% to 46.0 mol%, 28.0 mol% to 50.0 mol%, or 28.0 mol% to 50.0 mol%.

[0068] Similar to titanium dioxide, niobium oxide (Nb₂O₅) can be used in some aspects of this disclosure to increase the refractive index of a glass while maintaining a low density. However, niobium oxide introduces a yellow tint into the glass that cannot be bleached in the same way as titanium dioxide, leading to a loss of transmittance (particularly in the blue and UV ranges). Similar to titanium dioxide, niobium oxide can cause crystallization and / or phase separation in the melt. In some cases, niobium oxide can provide glass with high optical dispersion, significantly higher than that induced when titanium dioxide and some other refractive index enhancers are added at similar concentrations. The effect of niobium oxide is influenced by other components of the glass, and therefore determining the exact limits for niobium oxide can be challenging. Therefore, according to one aspect of this disclosure, the amount of niobium oxide is limited to less than or equal to 20 mol%, and in some cases, the glass may be free of or substantially free of niobium oxide. However, in some instances, the amount of niobium oxide present may exceed 20 mol%, depending on the composition of the glass and / or, for example, where high blue light transmittance is not a high priority.

[0069] In embodiments, the amount of niobium oxide (Nb₂O₅) contained in the glass composition can be greater than or equal to 0.0 mol% to less than or equal to 50.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of Nb₂O₅ contained in the glass composition can be: greater than or equal to 0.0 mol%, greater than or equal to 1.0 mol%, greater than or equal to 2.0 mol%, greater than or equal to 2.2 mol%, greater than or equal to 4.0 mol%, greater than or equal to 6.0 mol%, greater than or equal to 10.0 mol%, greater than or equal to 20.0 mol%, greater than or equal to 30.0 mol%, greater than or equal to 40.0 mol%, greater than or equal to 44.0 mol%, greater than or equal to 46.0 mol%, or greater than or equal to 48.0 mol%. In some other embodiments, the amount of Nb2O5 contained in the glass composition may be: less than or equal to 50.0 mol%, less than or equal to 48.0 mol%, less than or equal to 46.0 mol%, less than or equal to 44.0 mol%, less than or equal to 40.0 mol%, less than or equal to 30.0 mol%, less than or equal to 20.0 mol%, less than or equal to 12.3 mol%, less than or equal to 10.0 mol%, less than or equal to 6.0 mol%, less than or equal to 4.0 mol%, or less than or equal to 2.0 mol%. In some further embodiments, the amount of Nb₂O₅ contained in the glass composition may be: 0.0 mol% to 50.0 mol%, 0.0 mol% to 44.0 mol%, 0.0 mol% to 12.5 mol%, 2.2 mol% to 50.0 mol%, 2.2 mol% to 30.0 mol%, 1.0 mol% to 45.0 mol%, 2.0 mol% to 44.0 mol%, 2.0 mol% to 20.0 mol%, 4.0 mol% to 44.0 mol%, 4.0 mol% to 30.0 mol%, 4.0 mol% to 20.0 mol%, 6.0 mol% to 46.0 mol%, 6.0 mol% to 40.0 mol%, 6.0 mol% Up to 30.0 mol%, 6.0 mol% to 20.0 mol%, 10.0 mol% to 40.0 mol%, 10.0 mol% to 30.0 mol%, 20.0 mol% to 40.0 mol%, 20.0 mol% to 30.0 mol%, 30.0 mol% to 48.0 mol%, 30.0 mol% to 46.0 mol%, 30.0 mol% to 44.0 mol%, 30.0 mol% to 40.0 mol%, 10.0 mol% to 30.0 mol%, 0.3 mol% to 30.0 mol%, 0.3 mol% to 12.3 mol%, 12.0 mol% to 34.0 mol%, or 4.0 mol% to 30.0 mol%.

[0070] Zirconia (ZrO2) is another example of an oxide that can increase the refractive index of the glass of this disclosure while maintaining an acceptablely low density. In some cases, ZrO2 may provide a higher density to the glass compared to TiO2 and Nb2O5 for similar refractive index values. ZrO2 also increases the viscosity of the melt, which can help protect the melt from crystallization. Unlike other refractive index enhancers that can provide low density to the glass (e.g., TiO2 and Nb2O5), ZrO2 does not introduce color into the glass in the visible and near-UV ranges, which can help maintain the glass's high transmittance. However, high concentrations of zirconium oxide can lead to the crystallization of refractory minerals (e.g., zirconium oxide (ZrO2), zircon (ZrSiO4), and calcium zirconate (CaZrO3), etc.), which increases the liquidus temperature. As a result, crystallization may occur at lower viscosities, which may reduce the glass-forming ability of the melt (i.e., may increase the critical cooling rate). To address these challenges, according to one aspect of this disclosure, the zirconium oxide content in the glass is less than or equal to 20.0 mol%, and in some cases, the glass contains no or substantially no zirconium oxide. In some cases, such as when there are low requirements for glass forming capabilities, the glass may contain a higher amount of zirconium oxide.

[0071] In some embodiments, the amount of zirconium oxide (ZrO2) contained in the glass composition can be greater than or equal to 0.0 mol% to less than or equal to 25.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of ZrO2 contained in the glass composition can be: greater than or equal to 0.0 mol%, greater than or equal to 1.0 mol%, greater than or equal to 2.0 mol%, greater than or equal to 2.3 mol%, greater than or equal to 2.5 mol%, greater than or equal to 3.0 mol%, greater than or equal to 5.0 mol%, greater than or equal to 6.0 mol%, greater than or equal to 10.0 mol%, greater than or equal to 15.0 mol%, greater than or equal to 20.0 mol%, greater than or equal to 22.0 mol%, greater than or equal to 23.0 mol%, or greater than or equal to 24.0 mol%. In some other embodiments, the amount of ZrO2 contained in the glass composition may be: less than or equal to 25.0 mol%, less than or equal to 24.0 mol%, less than or equal to 23.0 mol%, less than or equal to 22.0 mol%, less than or equal to 20.0 mol%, less than or equal to 15.0 mol%, less than or equal to 10.0 mol%, less than or equal to 5.0 mol%, less than or equal to 3.0 mol%, less than or equal to 2.0 mol%, or less than or equal to 1.0 mol%. In some further embodiments, the amount of ZrO2 contained in the glass composition may be: 0.0 mol% to 25.0 mol%, 1.0 mol% to 22.0 mol%, 2.0 mol% to 22.0 mol%, 2.0 mol% to 10.0 mol%, 2.5 mol% to 25.0 mol%, 2.5 mol% to 20.0 mol%, 2.5 mol% to 13.0 mol%, 3.0 mol% to 25.0 mol%, 3.0 mol% to 23.0 mol%, 3.0 mol% to 10.0 mol%, 5.0 mol% to 25.0 mol%, 5.0 mol% to 23.0 mol%, 5.0 mol%. % to 20.0 mol%, 5.0 mol% to 10.0 mol%, 10.0 mol% to 25.0 mol%, 10.0 mol% to 23.0 mol%, 15.0 mol% to 24.0 mol%, 15.0 mol% to 25.0 mol%, 15.0 mol% to 23.0 mol%, 15.0 mol% to 22.0 mol%, 15.0 mol% to 20.0 mol%, 0.3 mol% to 15.0 mol%, 0.3 mol% to 13.0 mol%, 4.0 mol% to 15.0 mol%, 8.0 mol% to 15.0 mol%, or 8.0 mol% to 19.0 mol%.

[0072] In some embodiments, rare earth metal oxides may be added to the glass composition to increase the refractive index of the glass of this disclosure. Examples of rare earth metal oxides that may be added to the glass of this disclosure include La₂O₃, Gd₂O₃, Yb₂O₃, Y₂O₃, and Sc₂O₃. In some embodiments, the glass composition comprises at least one rare earth metal oxide selected from La₂O₃, Gd₂O₃, Yb₂O₃, and combinations thereof. Oxides of the latter two elements (Y₂O₃ and Sc₂O₃) can also provide the glass with a relatively low density, lower than that of titanium oxide and niobium oxide at similar refractive indices. However, scandium oxide (Sc₂O₃) can be expensive and therefore may not be desirable for mass production. In some cases, Sc₂O₃ may be acceptable when the cost of the glass batch is a lower priority. Yttrium oxide (Y₂O₃) is less expensive than scandium oxide. However, in some cases, Y₂O₃ may reduce the glass-forming ability of the glass (i.e., increase the critical cooling rate), even at lower concentrations. Therefore, according to some embodiments of this disclosure, the glass may be free of or substantially free of Y₂O₃. In some embodiments, the amount of yttrium oxide (Y₂O₃) contained in the glass composition may be greater than or equal to 0.0 mol% to less than or equal to 5.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of Y₂O₃ contained in the glass composition may be: greater than or equal to 0.0 mol%, greater than or equal to 0.2 mol%, greater than or equal to 0.4 mol%, greater than or equal to 0.6 mol%, greater than or equal to 1.0 mol%, greater than or equal to 2.0 mol%, greater than or equal to 3.0 mol%, greater than or equal to 4.0 mol%, greater than or equal to 4.4 mol%, greater than or equal to 4.6 mol%, or greater than or equal to 4.8 mol%. In some other embodiments, the amount of Y2O3 contained in the glass composition may be: less than or equal to 5.0 mol%, less than or equal to 4.8 mol%, less than or equal to 4.6 mol%, less than or equal to 4.4 mol%, less than or equal to 4.0 mol%, less than or equal to 3.0 mol%, less than or equal to 2.0 mol%, less than or equal to 1.0 mol%, less than or equal to 0.6 mol%, less than or equal to 0.4 mol%, or less than or equal to 0.2 mol%.In some further embodiments, the amount of Y2O3 contained in the glass composition may be: 0.0 mol% to 5.0 mol%, 0.0 mol% to 2.0 mol%, 0.0 mol% to 1.0 mol%, 0.2 mol% to 4.4 mol%, 0.2 mol% to 2.0 mol%, 0.4 mol% to 4.4 mol%, 0.6 mol% to 4.6 mol%, 0.6 mol% to 4.0 mol%, 1.0 mol% to 5.0 mol%, 1.0 mol% to 4.6 mol%, 1.0 mol% to 4.0 mol%, 2.0 mol% to 4.0 mol%, 3.0 mol% to 4.6 mol%, 3.0 mol% to 4.4 mol%, 3.0 mol% to 4.0 mol%, 2.0 mol% to 5.0 mol%, 1.0 mol% to 4.0 mol%, or 2.0 mol% to 4.0 mol%.

[0073] In some aspects, lanthanum oxide (La2O3) may be a preferred refractive index enhancer among rare earth metal oxides (besides Y2O3 and Sc2O3). Compared to several other rare earth metal oxides, La2O3 can provide a lower density for the glass of this disclosure at a similar refractive index. La2O3 also provides acceptable good glass forming for the glass composition and is one of the most cost-effective rare earth metal oxides. Therefore, in some aspects of this disclosure, the glass composition may contain at least some amount of La2O3. However, in some cases, when the concentration of La2O3 becomes too high, lanthanum oxide can cause the precipitation of refractory materials, such as lanthanum silicates (La4Si3O3). 12 Adding lanthanum oxides such as La₂SiO₅, La₂Si₂O₇, lanthanum borates (LaBO₃, LaB₃O₆), lanthanum niobates (LaNbO₄), lanthanum zircons (La₂ZrO₅, La₂Zr₂O₇), and lanthanum titanates (La₂TiO₅, La₂Ti₂O₇) can increase the liquidus temperature of the glass and may reduce the glass-forming ability of the composition. Furthermore, high concentrations of La₂O₃ may stimulate phase separation in the melt, leading to a loss of transmittance in the resulting glass. Similar negative effects occur when other rare earth metal oxides are added at high concentrations.

[0074] In some embodiments, the amount of lanthanum oxide (La₂O₃) contained in the glass composition can be greater than or equal to 0.0 mol% to less than or equal to 33.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of La₂O₃ contained in the glass composition can be: greater than or equal to 0.0 mol%, greater than or equal to 1.0 mol%, greater than or equal to 2.0 mol%, greater than or equal to 3.0 mol%, greater than or equal to 4.0 mol%, greater than or equal to 5.0 mol%, greater than or equal to 9.0 mol%, greater than or equal to 10.0 mol%, greater than or equal to 13.5 mol%, greater than or equal to 15.0 mol%, greater than or equal to 20.0 mol%, greater than or equal to 25.0 mol%, greater than or equal to 30.0 mol%, greater than or equal to 31.0 mol%, or greater than or equal to 32.0 mol%. In some other embodiments, the amount of La2O3 contained in the glass composition may be: less than or equal to 33.0 mol%, less than or equal to 32.0 mol%, less than or equal to 31.0 mol%, less than or equal to 30.0 mol%, less than or equal to 25.0 mol%, less than or equal to 20.0 mol%, less than or equal to 15.0 mol%, less than or equal to 10.0 mol%, less than or equal to 5.0 mol%, less than or equal to 3.0 mol%, less than or equal to 2.0 mol%, or less than or equal to 1.0 mol%. In some further embodiments, the amount of La2O3 contained in the glass composition may be: 0.0 mol% to 33.0 mol%, 0.0 mol% to 25.0 mol%, 1.0 mol% to 30.0 mol%, 1.0 mol% to 15.0 mol%, 2.0 mol% to 30.0 mol%, 2.0 mol% to 15.0 mol%, 3.0 mol% to 30.0 mol%, 3.0 mol% to 15.0 mol%, 5.0 mol% to 15.0 mol%, 10.0 mol% to 31.0 mol%. 10.0 mol% to 25.0 mol%, 13.5 mol% to 30.0 mol%, 15.0 mol% to 33.0 mol%, 15.0 mol% to 31.0 mol%, 20.0 mol% to 32.0 mol%, 20.0 mol% to 31.0 mol%, 20.0 mol% to 30.0 mol%, 25.0 mol% to 32.0 mol%, 2.0 mol% to 32.0 mol%, 13.0 mol% to 26.0 mol%, or 4.0 mol% to 13.0 mol%.

[0075] Optionally, other rare earth metal oxides, such as Gd₂O₃ and Yb₂O₃, may be added to the glass composition. Rare earth metal oxides (e.g., Gd₂O₃ and Yb₂O₃) can promote the maintenance of a high refractive index and good transmittance of the glass, but may undesirably increase the density of the glass. To address these challenges, some embodiments of this disclosure include limiting the RE content in the glass composition.m O n The content of rare earth metal oxides. In some embodiments, the total content of rare earth metal oxides (RE) in the glass composition. m O n The amount of ) can be greater than or equal to 0.0 mol% to less than or equal to 50.0 mol%, and all ranges and subranges between the above values. In some embodiments, the glass composition contains RE m O n The amount can be: greater than or equal to 0.0 mol%, greater than or equal to 2.0 mol%, greater than or equal to 4.0 mol%, greater than or equal to 6.0 mol%, greater than or equal to 10.0 mol%, greater than or equal to 20.0 mol%, greater than or equal to 30.0 mol%, greater than or equal to 40.0 mol%, greater than or equal to 44.0 mol%, greater than or equal to 46.0 mol%, or greater than or equal to 48.0 mol%. In some other embodiments, the glass composition contains RE m O n The amount can be: less than or equal to 50.0 mol%, less than or equal to 48.0 mol%, less than or equal to 46.0 mol%, less than or equal to 44.0 mol%, less than or equal to 40.0 mol%, less than or equal to 30.0 mol%, less than or equal to 20.0 mol%, less than or equal to 10.0 mol%, less than or equal to 6.0 mol%, less than or equal to 4.0 mol%, or less than or equal to 2.0 mol%. In some further embodiments, the glass composition contains RE m O n The amount can be: 0.0 mol% to 50.0 mol%, 0.0 mol% to 44.0 mol%, 0.0 mol% to 30.0 mol%, 2.0 mol% to 50.0 mol%, 2.0 mol% to 44.0 mol%, 2.0 mol% to 30.0 mol%, 2.0 mol% to 20.0 mol%, 4.0 mol% to 44.0 mol%, 4.0 mol% to 30.0 mol%, 4.0 mol% to 20.0 mol%, 6.0 mol% to 46.0 mol%, 6.0 mol% to 30.0 mol%, 6. 0 mol% to 20.0 mol%, 10.0 mol% to 46.0 mol%, 10.0 mol% to 30.0 mol%, 10.0 mol% to 20.0 mol%, 20.0 mol% to 46.0 mol%, 20.0 mol% to 30.0 mol%, 30.0 mol% to 50.0 mol%, 30.0 mol% to 48.0 mol%, 30.0 mol% to 44.0 mol%, 7.0 mol% to 25.0 mol%, 12.0 mol% to 30.0 mol%, or 2.0 mol% to 17.0 mol%.

[0076] In some embodiments, the glass of this disclosure may optionally contain additional and / or alternative refractive index enhancers (e.g., tungsten oxide (WO3), tantalum oxide (Ta2O5), thorium oxide (ThO2), bismuth oxide (Bi2O3)), which, if present, may be used in small amounts. In some embodiments, the glass of this disclosure contains no or substantially no tungsten oxide (WO3), tantalum oxide (Ta2O5), thorium oxide (ThO2), or bismuth oxide (Bi2O3). In some embodiments, the glass may optionally contain additional and / or alternative refractive index enhancers selected from: vanadium pentoxide (V2O5), molybdenum oxide (MoO3), germanium oxide (GeO2), tellurium oxide (TeO2), fluorides (e.g., ZrF4, LaF3, etc.), and thallium oxide (Tl2O). In some cases, refractive index enhancers such as V2O5, MoO3, GeO2, TeO2, fluorides, and Tl2O may not be preferred due to low transmittance, cost, and / or environmental considerations; however, in some cases, these refractive index enhancers can be used.

[0077] Ta₂O₅ can increase the density of glass and, in some cases, may cause the glass melt to crystallize upon cooling. Furthermore, in some cases, Ta₂O₅ can be expensive. Therefore, in some embodiments, it may be preferable to limit the amount of Ta₂O₅ in the glass to between 0.0 mol% and 5.0 mol%. In embodiments, the amount of tantalum oxide (Ta₂O₅) contained in the glass composition can be greater than or equal to 0.0 mol% to less than or equal to 5.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of Ta₂O₅ contained in the glass composition can be: greater than or equal to 0.0 mol%, greater than or equal to 0.2 mol%, greater than or equal to 0.4 mol%, greater than or equal to 0.6 mol%, greater than or equal to 1.0 mol%, greater than or equal to 2.0 mol%, greater than or equal to 3.0 mol%, greater than or equal to 4.0 mol%, greater than or equal to 4.4 mol%, greater than or equal to 4.6 mol%, or greater than or equal to 4.8 mol%. In some other embodiments, the amount of Ta2O5 contained in the glass composition may be: less than or equal to 5.0 mol%, less than or equal to 4.8 mol%, less than or equal to 4.6 mol%, less than or equal to 4.4 mol%, less than or equal to 4.0 mol%, less than or equal to 3.0 mol%, less than or equal to 2.0 mol%, less than or equal to 1.0 mol%, less than or equal to 0.6 mol%, less than or equal to 0.4 mol%, or less than or equal to 0.2 mol%. In some further embodiments, the amount of Ta2O5 contained in the glass composition may be: 0.0 mol% to 5.0 mol%, 0.0 mol% to 4.4 mol%, 0.0 mol% to 1.5 mol%, 0.2 mol% to 5.0 mol%, 0.2 mol% to 4.4 mol%, 0.2 mol% to 2.0 mol%, 0.6 mol% to 4.6 mol%, 0.6 mol% to 4.0 mol%, 1.0 mol% to 4.6 mol%, 1.0 mol% to 4.0 mol%, 1.0 mol% to 2.0 mol%, 2.0 mol% to 4.6 mol%, 2.0 mol% to 4.0 mol%, 3.0 mol% to 4.8 mol%, 3.0 mol% to 4.4 mol%, 3.0 mol% to 4.0 mol%, 2.0 mol% to 5.0 mol%, or 3.0 mol% to 5.0 mol%.

[0078] In some embodiments, the amount of Bi2O3 present in the glass can be from 0.0 mol% to 20.0 mol%. For example, the Bi2O3 present in the glass can be: 0.0 mol% to 20.0 mol%, 0.0 mol% to 15.0 mol%, 0.0 mol% to 10.0 mol%, 0.0 mol% to 5.0 mol%, 0.0 mol% to 1.0 mol%, 1.0 mol% to 20.0 mol%, 1.0 mol% to 15.0 mol%, 1.0 mol% to 10.0 mol%, 1.0 mol% to 5.0 mol%, 5.0 mol% to 20.0 mol%, 5.0 mol% to 15.0 mol%, 5.0 mol% to 10.0 mol%, or 10.0 mol% to 20.0 mol%. In some embodiments, the glass contains no or substantially no Bi2O3.

[0079] In some embodiments, the amount of thorium oxide (ThO2) contained in the glass composition can be greater than or equal to 0.0 mol% to less than or equal to 10.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of ThO2 contained in the glass composition can be: greater than or equal to 0.0 mol%, greater than or equal to 0.5 mol%, greater than or equal to 1.0 mol%, greater than or equal to 1.5 mol%, greater than or equal to 2.5 mol%, greater than or equal to 5.0 mol%, greater than or equal to 7.5 mol%, greater than or equal to 8.5 mol%, greater than or equal to 9.0 mol%, or greater than or equal to 9.5 mol%. In some other embodiments, the amount of ThO2 contained in the glass composition can be: less than or equal to 10.0 mol%, less than or equal to 9.5 mol%, less than or equal to 9.0 mol%, less than or equal to 8.5 mol%, less than or equal to 7.5 mol%, less than or equal to 5.0 mol%, less than or equal to 2.5 mol%, less than or equal to 1.5 mol%, less than or equal to 1.0 mol%, or less than or equal to 0.5 mol%. In some further embodiments, the amount of ThO2 contained in the glass composition may be: 0.0 mol% to 10.0 mol%, 0.0 mol% to 8.5 mol%, 0.0 mol% to 5.0 mol%, 0.0 mol% to 2.5 mol%, 1.0 mol% to 7.5 mol%, 1.5 mol% to 9.0 mol%, 1.5 mol% to 7.5 mol%, 2.5 mol% to 9.0 mol%, 5.0 mol% to 9.5 mol%, 5.0 mol% to 9.0 mol%, 5.0 mol% to 8.5 mol%, 5.0 mol% to 7.5 mol%, 7.5 mol% to 10.0 mol%, 7.5 mol% to 9.5 mol%, 1.4 mol% to 5.8 mol%, 1.4 mol% to 5.0 mol%, or 3.0 mol% to 7.0 mol%.

[0080] In some embodiments, the amount of tungsten oxide (WO3) contained in the glass composition may be greater than or equal to 0.0 mol% to less than or equal to 10.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of WO3 contained in the glass composition may be: greater than or equal to 0.0 mol%, greater than or equal to 1.0 mol%, greater than or equal to 2.5 mol%, greater than or equal to 5.0 mol%, or greater than or equal to 7.5 mol%. In some other embodiments, the amount of WO3 contained in the glass composition may be: less than or equal to 10.0 mol%, less than or equal to 7.5 mol%, less than or equal to 5.0 mol%, or less than or equal to 2.5 mol%. In some further embodiments, the amount of WO3 contained in the glass composition may be: 0.0 mol% to 10.0 mol%, 0.0 mol% to 7.5 mol%, 0.0 mol% to 5.0 mol%, 0.0 mol% to 2.5 mol%, 2.5 mol% to 10.0 mol%, 2.5 mol% to 7.5 mol%, 2.5 mol% to 5.0 mol%, 5.0 mol% to 10.0 mol%, 5.0 mol% to 7.5 mol%, 2.0 mol% to 5.0 mol%, 5.3 mol% to 9.5 mol%, or 6.6 mol% to 9.6 mol%.

[0081] In some embodiments, the amount of germanium oxide (GeO2) contained in the glass composition can be greater than or equal to 0.0 mol% to less than or equal to 10.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of GeO2 contained in the glass composition can be: greater than or equal to 0.0 mol%, greater than or equal to 0.5 mol%, greater than or equal to 1.0 mol%, greater than or equal to 1.5 mol%, greater than or equal to 2.5 mol%, greater than or equal to 5.0 mol%, greater than or equal to 7.5 mol%, greater than or equal to 8.5 mol%, greater than or equal to 9.0 mol%, or greater than or equal to 9.5 mol%. In some other embodiments, the amount of GeO2 contained in the glass composition can be: less than or equal to 10.0 mol%, less than or equal to 9.5 mol%, less than or equal to 9.0 mol%, less than or equal to 8.5 mol%, less than or equal to 7.5 mol%, less than or equal to 5.0 mol%, less than or equal to 2.5 mol%, less than or equal to 1.5 mol%, less than or equal to 1.0 mol%, or less than or equal to 0.5 mol%. In some further embodiments, the amount of GeO2 contained in the glass composition may be: 0.0 mol% to 10.0 mol%, 0.0 mol% to 8.5 mol%, 0.0 mol% to 0.5 mol%, 0.5 mol% to 8.5 mol%, 1.0 mol% to 10.0 mol%, 1.0 mol% to 9.0 mol%, 1.0 mol% to 7.5 mol%, 1.5 mol% to 7.5 mol%, 2.5 mol% to 9.0 mol%, 2.5 mol% to 7.5 mol%, 5.0 mol% to 10.0 mol%, 1.4 mol% to 5.5 mol%, 5.4 mol% to 8.3 mol%, or 1.9 mol% to 6.8 mol%.

[0082] In some embodiments, the amount of tellurium oxide (TeO2) contained in the glass composition can be greater than or equal to 0.0 mol% to less than or equal to 10.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of TeO2 contained in the glass composition can be: greater than or equal to 0.0 mol%, greater than or equal to 0.5 mol%, greater than or equal to 1.0 mol%, greater than or equal to 1.5 mol%, greater than or equal to 2.5 mol%, greater than or equal to 5.0 mol%, greater than or equal to 7.5 mol%, greater than or equal to 8.5 mol%, greater than or equal to 9.0 mol%, or greater than or equal to 9.5 mol%. In some other embodiments, the amount of TeO2 contained in the glass composition can be: less than or equal to 10.0 mol%, less than or equal to 9.5 mol%, less than or equal to 9.0 mol%, less than or equal to 8.5 mol%, less than or equal to 7.5 mol%, less than or equal to 5.0 mol%, less than or equal to 2.5 mol%, less than or equal to 1.5 mol%, less than or equal to 1.0 mol%, or less than or equal to 0.5 mol%. In some further embodiments, the amount of TeO2 contained in the glass composition may be: 0.0 mol% to 10.0 mol%, 0.0 mol% to 8.5 mol%, 0.0 mol% to 2.5 mol%, 0.5 mol% to 8.5 mol%, 0.5 mol% to 2.5 mol%, 1.0 mol% to 9.0 mol%, 1.5 mol% to 9.0 mol%, 5.0 mol% to 10.0 mol%, 5.0 mol% to 9.5 mol%, 5.0 mol% to 9.0 mol%, 5.0 mol% to 8.5 mol%, 7.5 mol% to 9.5 mol%, 1.4 mol% to 9.0 mol%, 0.7 mol% to 4.2 mol%, or 3.0 mol% to 7.0 mol%. TeO2 can be costly and may result in an undesirable increase in glass density for some applications. Therefore, the glass preferably has less than 10.0 mol% TeO2. In some embodiments, the glass may contain no or substantially no TeO2.

[0083] In some embodiments, the amount of molybdenum oxide (MoO3) contained in the glass composition can be greater than or equal to 0.0 mol% to less than or equal to 10.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of MoO3 contained in the glass composition can be: greater than or equal to 0.0 mol%, greater than or equal to 0.5 mol%, greater than or equal to 1.0 mol%, greater than or equal to 1.5 mol%, greater than or equal to 2.5 mol%, greater than or equal to 5.0 mol%, greater than or equal to 7.5 mol%, greater than or equal to 8.5 mol%, greater than or equal to 9.0 mol%, or greater than or equal to 9.5 mol%. In some other embodiments, the amount of MoO3 contained in the glass composition can be: less than or equal to 10.0 mol%, less than or equal to 9.5 mol%, less than or equal to 9.0 mol%, less than or equal to 8.5 mol%, less than or equal to 7.5 mol%, less than or equal to 5.0 mol%, less than or equal to 2.5 mol%, less than or equal to 1.5 mol%, less than or equal to 1.0 mol%, or less than or equal to 0.5 mol%. In some further embodiments, the amount of MoO3 contained in the glass composition may be: 0.0 mol% to 10.0 mol%, 0.0 mol% to 8.5 mol%, 0.0 mol% to 3.0 mol%, 0.5 mol% to 10.0 mol%, 0.5 mol% to 8.5 mol%, 0.5 mol% to 2.5 mol%, 1.0 mol% to 10.0 mol%, 1.5 mol% to 9.0 mol%, 1.5 mol% to 7.5 mol%, 2.5 mol% to 10.0 mol%, 2.5 mol% to 9.0 mol%, 2.5 mol% to 7.5 mol%, 5.0 mol% to 9.5 mol%, 5.0 mol% to 9.0 mol%, 7.5 mol% to 9.5 mol%, 3.0 mol% to 7.0 mol%, 0.5 mol% to 5.5 mol%, or 4.5 mol% to 9.2 mol%.

[0084] In some embodiments, the amount of alumina (Al₂O₃) contained in the glass composition can be greater than or equal to 0.0 mol% to less than or equal to 5.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of Al₂O₃ contained in the glass composition can be: greater than or equal to 0.0 mol%, greater than or equal to 0.2 mol%, greater than or equal to 0.4 mol%, greater than or equal to 0.6 mol%, greater than or equal to 1.0 mol%, greater than or equal to 2.0 mol%, greater than or equal to 3.0 mol%, greater than or equal to 4.0 mol%, greater than or equal to 4.4 mol%, greater than or equal to 4.6 mol%, or greater than or equal to 4.8 mol%. In some other embodiments, the amount of Al2O3 contained in the glass composition may be: less than or equal to 5.0 mol%, less than or equal to 4.8 mol%, less than or equal to 4.6 mol%, less than or equal to 4.4 mol%, less than or equal to 4.0 mol%, less than or equal to 3.0 mol%, less than or equal to 2.0 mol%, less than or equal to 1.0 mol%, less than or equal to 0.6 mol%, less than or equal to 0.4 mol%, or less than or equal to 0.2 mol%. In some further embodiments, the amount of Al2O3 contained in the glass composition may be: 0.0 mol% to 5.0 mol%, 0.0 mol% to 4.4 mol%, 0.0 mol% to 2.5 mol%, 0.0 mol% to 2.0 mol%, 0.2 mol% to 5.0 mol%, 0.2 mol% to 2.0 mol%, 0.4 mol% to 2.0 mol%, 0.6 mol% to 4.6 mol%, 0.6 mol% to 4.0 mol%, 0.6 mol% to 2.0 mol%, 1.0 mol% to 5.0 mol%, 1.0 mol% to 4.6 mol%, 1.0 mol% to 4.0 mol%, 1.0 mol% to 2.0 mol%, 2.0 mol% to 4.6 mol%, 2.0 mol% to 4.0 mol%, 3.0 mol% to 4.4 mol%, 3.0 mol% to 4.0 mol%, 1.0 mol% to 3.0 mol%, or 2.0 mol% to 4.0 mol%.

[0085] In some embodiments, the amount of gallium oxide (Ga2O3) contained in the glass composition can be greater than or equal to 0.0 mol% to less than or equal to 10.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of Ga2O3 contained in the glass composition can be: greater than or equal to 0.0 mol%, greater than or equal to 0.5 mol%, greater than or equal to 1.0 mol%, greater than or equal to 1.5 mol%, greater than or equal to 2.5 mol%, greater than or equal to 5.0 mol%, greater than or equal to 7.5 mol%, greater than or equal to 8.5 mol%, greater than or equal to 9.0 mol%, or greater than or equal to 9.5 mol%. In some other embodiments, the amount of Ga2O3 contained in the glass composition can be: less than or equal to 10.0 mol%, less than or equal to 9.5 mol%, less than or equal to 9.0 mol%, less than or equal to 8.5 mol%, less than or equal to 7.5 mol%, less than or equal to 5.0 mol%, less than or equal to 2.5 mol%, less than or equal to 1.5 mol%, less than or equal to 1.0 mol%, or less than or equal to 0.5 mol%. In some further embodiments, the amount of Ga2O3 contained in the glass composition may be: 0.0 mol% to 10.0 mol%, 0.5 mol% to 2.5 mol%, 1.0 mol% to 10.0 mol%, 1.0 mol% to 7.5 mol%, 1.5 mol% to 9.0 mol%, 1.5 mol% to 7.5 mol%, 2.5 mol% to 7.5 mol%, 5.0 mol% to 9.5 mol%, 5.0 mol% to 9.0 mol%, 5.0 mol% to 8.5 mol%, 7.5 mol% to 9.5 mol%, 2.4 mol% to 9.4 mol%, 5.0 mol% to 9.2 mol%, or 5.7 mol% to 9.0 mol%.

[0086] In some embodiments, the glass of this disclosure may be free of or substantially free of fluorine. In some embodiments, the glass may contain 0.0 atomic% to 1.0 atomic% of fluorine. For example, the fluorine contained in the glass may be: 0.0 atomic% to 1.0 atomic%, 0.0 atomic% to 0.5 atomic%, 0.0 atomic% to 0.25 atomic%, or 0.0 atomic% to 0.1 atomic%.

[0087] According to embodiments of this disclosure, the glass may contain one or more modifiers. As described above, the term "modifier" refers to an oxide of a monovalent or divalent metal, i.e., M₂O or MO, where "M" represents a metal. Modifiers may be added to the glass compositions of this disclosure to promote improved glass-forming ability of the melt, i.e., to reduce the critical cooling rate. Examples of modifiers that can be used in the glasses of this disclosure include basic and alkaline earth modifiers (e.g., CaO, MgO, BaO, Li₂O, Na₂O, and K₂O), as well as other modifiers (e.g., ZnO and Ag₂O). According to one embodiment, the glass composition may contain CaO and / or Li₂O, which have been found to provide the desired refractive index to density ratio of the glass. In some embodiments, other basic and alkaline earth metal oxides (e.g., Na₂O, K₂O, MgO, SrO, BaO, etc.) and other modifiers that do not provide any color (e.g., ZnO, Ag₂O, etc.) may be included in the glass composition. While these other modifiers may not contribute to providing the desired refractive index and / or density as effectively as CaO and Li₂O, they can be added to the glass composition to provide additional properties. For example, barium oxide (BaO), potassium oxide (K₂O), sodium oxide (Na₂O), etc., can be added to increase the solubility of refractive index enhancers (e.g., TiO₂, Nb₂O₅, ZrO₂, etc.) in the glass melt, resulting in an overall increase in the glass's refractive index and / or an increase in the refractive index to density ratio. According to one embodiment of this disclosure, the glass may contain at least CaO as a modifier because CaO has been found to provide a good balance between the desired density, refractive index, and glass formability properties. Thus, in many examples of this disclosure, all or at least a portion of the modifiers present in the glass composition are in the form of CaO. In some embodiments, the glass may contain no or substantially no modifiers.

[0088] In some embodiments, the amount of calcium oxide (CaO) contained in the glass composition may be greater than or equal to 0.0 mol% to less than or equal to 30.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of CaO contained in the glass composition may be: greater than or equal to 0.0 mol%, greater than or equal to 1.0 mol%, greater than or equal to 2.0 mol%, greater than or equal to 3.0 mol%, greater than or equal to 5.0 mol%, greater than or equal to 10.0 mol%, greater than or equal to 15.0 mol%, greater than or equal to 20.0 mol%, greater than or equal to 25.0 mol%, greater than or equal to 27.0 mol%, greater than or equal to 28.0 mol%, or greater than or equal to 29.0 mol%. In some other embodiments, the amount of CaO contained in the glass composition may be: less than or equal to 30.0 mol%, less than or equal to 29.0 mol%, less than or equal to 28.0 mol%, less than or equal to 27.0 mol%, less than or equal to 25.0 mol%, less than or equal to 20.0 mol%, less than or equal to 15.0 mol%, less than or equal to 10.0 mol%, less than or equal to 5.0 mol%, less than or equal to 3.0 mol%, less than or equal to 2.0 mol%, or less than or equal to 1.0 mol%. In some further embodiments, the amount of CaO contained in the glass composition may be: 0.0 mol% to 30.0 mol%, 0.0 mol% to 25.0 mol%, 0.0 mol% to 15.0 mol%, 1.0 mol% to 15.0 mol%, 2.0 mol% to 27.0 mol%, 2.0 mol% to 15.0 mol%, 3.0 mol% to 27.0 mol%, 5.0 mol% to 25.0 mol%, 10.0 mol% to 28.0 mol%, 10.0 mol% to 15.0 mol%, 15.0 mol% to 30.0 mol%, 15.0 mol% to 28.0 mol%, 15.0 mol% to 25.0 mol%, 10.0 mol% to 21.0 mol%, 1.0 mol% to 27.0 mol%, or 13.0 mol% to 22.0 mol%.

[0089] In some embodiments, the amount of zinc oxide (ZnO) contained in the glass composition can be greater than or equal to 0.0 mol% to less than or equal to 10.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of ZnO contained in the glass composition can be: greater than or equal to 0.0 mol%, greater than or equal to 0.5 mol%, greater than or equal to 1.0 mol%, greater than or equal to 1.5 mol%, greater than or equal to 2.5 mol%, greater than or equal to 5.0 mol%, greater than or equal to 7.5 mol%, greater than or equal to 8.5 mol%, greater than or equal to 9.0 mol%, or greater than or equal to 9.5 mol%. In some other embodiments, the amount of ZnO contained in the glass composition can be: less than or equal to 10.0 mol%, less than or equal to 9.5 mol%, less than or equal to 9.0 mol%, less than or equal to 8.5 mol%, less than or equal to 7.5 mol%, less than or equal to 5.0 mol%, less than or equal to 2.5 mol%, less than or equal to 1.5 mol%, less than or equal to 1.0 mol%, or less than or equal to 0.5 mol%. In some further embodiments, the amount of ZnO contained in the glass composition may be: 0.0 mol% to 10.0 mol%, 0.0 mol% to 5.5 mol%, 0.0 mol% to 2.5 mol%, 0.5 mol% to 10.0 mol%, 1.0 mol% to 9.0 mol%, 1.0 mol% to 7.5 mol%, 1.5 mol% to 9.0 mol%, 1.5 mol% to 7.5 mol%, 2.5 mol% to 7.5 mol%, 5.0 mol% to 9.5 mol%, 5.0 mol% to 9.0 mol%, 5.0 mol% to 8.5 mol%, 5.0 mol% to 7.5 mol%, 7.5 mol% to 9.5 mol%, 2.9 mol% to 7.2 mol%, 0.7 mol% to 7.7 mol%, or 6.5 mol% to 9.5 mol%.

[0090] In some embodiments, the amount of lithium oxide (Li₂O) contained in the glass composition can be greater than or equal to 0.0 mol% to less than or equal to 10.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of Li₂O contained in the glass composition can be: greater than or equal to 0.0 mol%, greater than or equal to 0.5 mol%, greater than or equal to 1.0 mol%, greater than or equal to 1.5 mol%, greater than or equal to 2.5 mol%, greater than or equal to 3.99 mol%, greater than or equal to 5.0 mol%, greater than or equal to 7.5 mol%, greater than or equal to 8.5 mol%, greater than or equal to 9.0 mol%, or greater than or equal to 9.5 mol%. In some other embodiments, the amount of Li2O contained in the glass composition may be: less than or equal to 10.0 mol%, less than or equal to 9.5 mol%, less than or equal to 9.0 mol%, less than or equal to 8.5 mol%, less than or equal to 7.5 mol%, less than or equal to 5.0 mol%, less than or equal to 2.5 mol%, less than or equal to 1.5 mol%, less than or equal to 1.0 mol%, or less than or equal to 0.5 mol%. In some further embodiments, the amount of Li2O contained in the glass composition may be: 0.0 mol% to 10.0 mol%, 0.0 mol% to 8.5 mol%, 0.0 mol% to 8.0 mol%, 0.0 mol% to 2.5 mol%, 0.5 mol% to 8.5 mol%, 0.5 mol% to 2.5 mol%, 1.0 mol% to 9.0 mol%, 1.0 mol% to 7.5 mol%, 1.5 mol% to 10.0 mol%, 1.5 mol% to 9.0 mol%, 2.5 mol% to 9.0 mol%, 5.0 mol% to 8.5 mol%, 5.0 mol% to 7.5 mol%, 7.5 mol% to 9.5 mol%, 0.0 mol% to 4.7 mol%, 2.5 mol% to 7.5 mol%, or 1.8 mol% to 8.2 mol%.

[0091] In some embodiments, the amount of barium oxide (BaO) contained in the glass composition may be greater than or equal to 0.0 mol% to less than or equal to 15.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of BaO contained in the glass composition may be: greater than or equal to 0.0 mol%, greater than or equal to 4.0 mol%, greater than or equal to 5.0 mol%, or greater than or equal to 10.0 mol%. In some other embodiments, the amount of BaO contained in the glass composition may be: less than or equal to 15.0 mol%, less than or equal to 10.0 mol%, or less than or equal to 5.0 mol%. In some further embodiments, the amount of BaO contained in the glass composition may be: 0.0 mol% to 15.0 mol%, 0.0 mol% to 10.0 mol%, 0.0 mol% to 5.0 mol%, 5.0 mol% to 15.0 mol%, 5.0 mol% to 10.0 mol%, 3.5 mol% to 10.5 mol%, 6.5 mol% to 11.5 mol%, or 8.9 mol% to 13.4 mol%.

[0092] In some embodiments, the amount of magnesium oxide (MgO) contained in the glass composition may be greater than or equal to 0.0 mol% to less than or equal to 15.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of MgO contained in the glass composition may be: greater than or equal to 0.0 mol%, greater than or equal to 1.0 mol%, greater than or equal to 2.0 mol%, greater than or equal to 3.0 mol%, greater than or equal to 5.0 mol%, greater than or equal to 10.0 mol%, greater than or equal to 12.0 mol%, greater than or equal to 13.0 mol%, or greater than or equal to 14.0 mol%. In some other embodiments, the amount of MgO contained in the glass composition may be: less than or equal to 15.0 mol%, less than or equal to 14.0 mol%, less than or equal to 13.0 mol%, less than or equal to 12.0 mol%, less than or equal to 10.0 mol%, less than or equal to 5.0 mol%, less than or equal to 3.0 mol%, less than or equal to 2.0 mol%, or less than or equal to 1.0 mol%. In some further embodiments, the amount of MgO contained in the glass composition may be: 0.0 mol% to 15.0 mol%, 1.0 mol% to 13.0 mol%, 2.0 mol% to 13.0 mol%, 2.0 mol% to 10.0 mol%, 3.0 mol% to 13.0 mol%, 5.0 mol% to 14.0 mol%, 5.0 mol% to 13.0 mol%, 5.0 mol% to 12.0 mol%, 5.0 mol% to 10.0 mol%, 10.0 mol% to 14.0 mol%, 9.7 mol% to 13.5 mol%, 2.1 mol% to 7.5 mol%, or 5.4 mol% to 11.9 mol%.

[0093] In some embodiments, the amount of sodium oxide (Na₂O) contained in the glass composition may be greater than or equal to 0.0 mol% to less than or equal to 10.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of Na₂O contained in the glass composition may be: greater than or equal to 0.0 mol%, greater than or equal to 2.5 mol%, greater than or equal to 5.0 mol%, or greater than or equal to 7.5 mol%. In some other embodiments, the amount of Na₂O contained in the glass composition may be: less than or equal to 10.0 mol%, less than or equal to 7.5 mol%, less than or equal to 5.0 mol%, or less than or equal to 2.5 mol%. In some further embodiments, the amount of Na2O contained in the glass composition may be: 0.0 mol% to 10.0 mol%, 0.0 mol% to 7.5 mol%, 0.0 mol% to 5.0 mol%, 0.0 mol% to 2.5 mol%, 2.5 mol% to 10.0 mol%, 2.5 mol% to 7.5 mol%, 2.5 mol% to 5.0 mol%, 5.0 mol% to 10.0 mol%, 5.0 mol% to 7.5 mol%, 2.6 mol% to 9.9 mol%, 0.2 mol% to 6.9 mol%, or 1.1 mol% to 6.9 mol%.

[0094] In some embodiments, the amount of potassium oxide (K₂O) contained in the glass composition may be greater than or equal to 0.0 mol% to less than or equal to 10.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of K₂O contained in the glass composition may be: greater than or equal to 0.0 mol%, greater than or equal to 2.0 mol%, greater than or equal to 2.5 mol%, greater than or equal to 5.0 mol%, or greater than or equal to 7.5 mol%. In some other embodiments, the amount of K₂O contained in the glass composition may be: less than or equal to 10.0 mol%, less than or equal to 7.5 mol%, less than or equal to 5.0 mol%, or less than or equal to 2.5 mol%. In some further embodiments, the amount of K2O contained in the glass composition may be: 0.0 mol% to 10.0 mol%, 0.0 mol% to 7.5 mol%, 0.0 mol% to 5.0 mol%, 0.0 mol% to 2.5 mol%, 2.5 mol% to 10.0 mol%, 2.5 mol% to 7.5 mol%, 2.5 mol% to 5.0 mol%, 5.0 mol% to 10.0 mol%, 5.0 mol% to 7.5 mol%, 4.4 mol% to 7.6 mol%, 3.8 mol% to 7.6 mol%, or 2.1 mol% to 5.8 mol%.

[0095] In some embodiments, the amount of strontium oxide (SrO) contained in the glass composition can be greater than or equal to 0.0 mol% to less than or equal to 10.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of SrO contained in the glass composition can be: greater than or equal to 0.0 mol%, greater than or equal to 2.5 mol%, greater than or equal to 5.0 mol%, or greater than or equal to 7.5 mol%. In some embodiments, the amount of SrO contained in the glass composition can be: less than or equal to 10.0 mol%, less than or equal to 7.5 mol%, less than or equal to 5.0 mol%, or less than or equal to 2.5 mol%. In some further embodiments, the amount of SrO contained in the glass composition may be: 0.0 mol% to 10.0 mol%, 0.0 mol% to 7.5 mol%, 0.0 mol% to 5.0 mol%, 0.0 mol% to 2.5 mol%, 2.5 mol% to 10.0 mol%, 2.5 mol% to 7.5 mol%, 2.5 mol% to 5.0 mol%, 5.0 mol% to 10.0 mol%, 5.0 mol% to 7.5 mol%, 3.0 mol% to 6.5 mol%, 3.0 mol% to 6.5 mol%, or 4.0 mol% to 7.3 mol%.

[0096] In some embodiments, the total amount of monovalent metal oxides (R2O) contained in the glass composition can be greater than or equal to 0.0 mol% to less than or equal to 15.0 mol%, and all ranges and subranges between the above values. Examples of monovalent metal oxides R2O include alkali metal oxides, Ag2O, Tl2O, and other monovalent oxides. In some embodiments, the amount of R2O contained in the glass composition can be: greater than or equal to 0.0 mol%, greater than or equal to 1.0 mol%, greater than or equal to 2.0 mol%, greater than or equal to 3.0 mol%, greater than or equal to 5.0 mol%, greater than or equal to 10.0 mol%, greater than or equal to 12.0 mol%, greater than or equal to 13.0 mol%, or greater than or equal to 14.0 mol%. In some other embodiments, the amount of R2O contained in the glass composition may be: less than or equal to 15.0 mol%, less than or equal to 14.0 mol%, less than or equal to 13.0 mol%, less than or equal to 12.0 mol%, less than or equal to 10.0 mol%, less than or equal to 5.0 mol%, less than or equal to 3.0 mol%, less than or equal to 2.0 mol%, or less than or equal to 1.0 mol%. In some further embodiments, the amount of R2O contained in the glass composition may be: 0.0 mol% to 15.0 mol%, 0.0 mol% to 12.0 mol%, 1.0 mol% to 13.0 mol%, 1.0 mol% to 10.0 mol%, 2.0 mol% to 13.0 mol%, 3.0 mol% to 13.0 mol%, 5.0 mol% to 15.0 mol%, 5.0 mol% to 13.0 mol%, 5.0 mol% to 12.0 mol%, 5.0 mol% to 10.0 mol%, 10.0 mol% to 14.0 mol%, 10.0 mol% to 13.0 mol%, 4.4 mol% to 14.7 mol%, 4.5 mol% to 9.5 mol%, or 4.0 mol% to 10.5 mol%.

[0097] In some embodiments, the amount of the sum of As₂O₃ and Sb₂O₃ (As₂O₃ + Sb₂O₃) contained in the glass composition, expressed in mol%, can be greater than or equal to 0.0 mol% to less than or equal to 5.0 mol%, and all ranges and subranges between the above values. In some embodiments, the amount of (As₂O₃ + Sb₂O₃) contained in the glass composition can be: greater than or equal to 0.0 mol%, greater than or equal to 0.2 mol%, greater than or equal to 0.4 mol%, greater than or equal to 0.6 mol%, greater than or equal to 1.0 mol%, greater than or equal to 2.0 mol%, greater than or equal to 3.0 mol%, greater than or equal to 4.0 mol%, greater than or equal to 4.4 mol%, greater than or equal to 4.6 mol%, or greater than or equal to 4.8 mol%. In some other embodiments, the amount of (As2O3+Sb2O3) contained in the glass composition may be: less than or equal to 5.0 mol%, less than or equal to 4.8 mol%, less than or equal to 4.6 mol%, less than or equal to 4.4 mol%, less than or equal to 4.0 mol%, less than or equal to 3.0 mol%, less than or equal to 2.0 mol%, less than or equal to 1.0 mol%, less than or equal to 0.6 mol%, less than or equal to 0.4 mol%, or less than or equal to 0.2 mol%. In some further embodiments, the amount of (As₂O₃ + Sb₂O₃) contained in the glass composition may be: 0.0 mol% to 5.0 mol%, 0.0 mol% to 4.4 mol%, 0.0 mol% to 2.0 mol%, 0.0 mol% to 1.0 mol%, 0.2 mol% to 5.0 mol%, 0.2 mol% to 2.0 mol%, 0.4 mol% to 5.0 mol%, 0.4 mol% to 4.4 mol%, 0.4 mol% to 2.0 mol%, 0.6 mol% to 4.6 mol%, 0.6 mol% to 2.0 mol%, 1.0 mol% to 4.6 mol%, 1.0 mol% to 4.0 mol%, 2.0 mol% to 4.6 mol%, 2.0 mol% to 4.0 mol%, 3.0 mol% to 4.6 mol%, 3.0 mol% to 4.4 mol%, 1.0 mol% to 2.0 mol%, 2.0 mol% to 5.0 mol%, or 1.0 mol% to 3.0 mol%.

[0098] In some embodiments, the amount of the sum of ZnO and Y2O3 (ZnO + Y2O3) contained in the glass composition, expressed in mol%, can be greater than or equal to 0.0 mol% to less than or equal to 5.0 mol%, and all ranges and subranges between these values. In some embodiments, the amount of (ZnO + Y2O3) contained in the glass composition can be: greater than or equal to 0.0 mol%, greater than or equal to 0.2 mol%, greater than or equal to 0.4 mol%, greater than or equal to 0.6 mol%, greater than or equal to 1.0 mol%, greater than or equal to 2.0 mol%, greater than or equal to 3.0 mol%, greater than or equal to 4.0 mol%, greater than or equal to 4.4 mol%, greater than or equal to 4.6 mol%, or greater than or equal to 4.8 mol%. In some other embodiments, the amount of (ZnO+Y2O3) contained in the glass composition may be: less than or equal to 5.0 mol%, less than or equal to 4.8 mol%, less than or equal to 4.6 mol%, less than or equal to 4.4 mol%, less than or equal to 4.0 mol%, less than or equal to 3.0 mol%, less than or equal to 2.0 mol%, less than or equal to 1.0 mol%, less than or equal to 0.6 mol%, less than or equal to 0.4 mol%, or less than or equal to 0.2 mol%. In some further embodiments, the amount of (ZnO+Y2O3) contained in the glass composition may be: 0.0 mol% to 5.0 mol%, 0.0 mol% to 2.5 mol%, 0.0 mol% to 2.0 mol%, 0.2 mol% to 4.4 mol%, 0.2 mol% to 2.0 mol%, 0.4 mol% to 4.4 mol%, 0.4 mol% to 2.0 mol%, 0.6 mol% to 4.6 mol%, 0.6 mol% to 4.0 mol%, 0.6 mol% to 2.0 mol%, 1.0 mol% to 4.0 mol%, 1.0 mol% to 2.0 mol%, 2.0 mol% to 4.6 mol%, 3.0 mol% to 4.6 mol%, 2.0 mol% to 4.0 mol%, or 3.0 mol% to 5.0 mol%.

[0099] In some embodiments, the glass composition contains (RE) in mol% quantities. m O n The sum of (+TiO2+Nb2O5+ZrO2+Bi2O3+WO3) can be greater than or equal to 0.0 mol% to less than or equal to 5.0 mol%, and all ranges and subranges between the above values. In some embodiments, the glass composition contains (RE) m O nThe amount of (+TiO2+Nb2O5+ZrO2+Bi2O3+WO3) can be: greater than or equal to 0.0 mol%, greater than or equal to 0.2 mol%, greater than or equal to 0.4 mol%, greater than or equal to 0.6 mol%, greater than or equal to 1.0 mol%, greater than or equal to 2.0 mol%, greater than or equal to 3.0 mol%, greater than or equal to 4.0 mol%, greater than or equal to 4.4 mol%, greater than or equal to 4.6 mol%, greater than or equal to 4.8 mol%, or greater than or equal to 5.0 mol%. In some other embodiments, the glass composition contains (RE) m O n The amount of (+TiO2+Nb2O5+ZrO2+Bi2O3+WO3) can be: less than or equal to 5.0 mol%, less than or equal to 4.8 mol%, less than or equal to 4.6 mol%, less than or equal to 4.4 mol%, less than or equal to 4.0 mol%, less than or equal to 3.0 mol%, less than or equal to 2.0 mol%, less than or equal to 1.0 mol%, less than or equal to 0.6 mol%, less than or equal to 0.4 mol%, or less than or equal to 0.2 mol%. In some further embodiments, the glass composition contains (RE m O n The sum of (TiO2 + Nb2O5 + ZrO2 + Bi2O3 + WO3) can be greater than or equal to 25.0 mol% to less than or equal to 75.0 mol%, and all ranges and subranges between the above values. In some embodiments, the glass composition contains (RE) m O n The amount of (+TiO2+Nb2O5+ZrO2+Bi2O3+WO3) can be greater than or equal to 25.0 mol%, greater than or equal to 30.0 mol%, greater than or equal to 40.0 mol%, greater than or equal to 50.0 mol%, greater than or equal to 60.0 mol%, or greater than or equal to 70.0 mol%. In some other embodiments, the glass composition contains (RE) m O n The amount of (+TiO2+Nb2O5+ZrO2+Bi2O3+WO3) can be: less than or equal to 75.0 mol%, less than or equal to 70.0 mol%, less than or equal to 60.0 mol%, less than or equal to 50.0 mol%, less than or equal to 40.0 mol%, or less than or equal to 30.0 mol%. In some further embodiments, the glass composition contains (RE) m O nThe amount of (TiO2+Nb2O5+ZrO2+Bi2O3+WO3) can be: 25.0 mol% to 75.0 mol%, 25.0 mol% to 60.0 mol%, 25.0 mol% to 40.0 mol%, 30.0 mol% to 75.0 mol%, 30.0 mol% to 70.0 mol%, 30.0 mol% to 60.0 mol%, 30.0 mol% to 50.0 mol%, 30.0 mol% to 40.0 mol%, 40.0 mol% to 75.0 mol%. 40.0 mol% to 70.0 mol%, 40.0 mol% to 60.0 mol%, 40.0 mol% to 50.0 mol%, 50.0 mol% to 75.0 mol%, 50.0 mol% to 70.0 mol%, 50.0 mol% to 60.0 mol%, 60.0 mol% to 75.0 mol%, 60.0 mol% to 70.0 mol%, 39.0 mol% to 54.0 mol%, 32.0 mol% to 65.0 mol%, or 53.0 mol% to 66.0 mol%.

[0100] In some embodiments, the glass composition may have a (R₂O + RO-BaO) content of greater than or equal to 0.0 mol% to less than or equal to 20.0 mol%, and all ranges and subranges between the above values. In some embodiments, the glass composition may have a (R₂O + RO-BaO) content of: greater than or equal to 0.0 mol%, greater than or equal to 1.0 mol%, greater than or equal to 2.0 mol%, greater than or equal to 3.0 mol%, greater than or equal to 5.0 mol%, greater than or equal to 10.0 mol%, greater than or equal to 15.0 mol%, greater than or equal to 17.0 mol%, greater than or equal to 18.0 mol%, or greater than or equal to 19.0 mol%. In some other embodiments, the glass composition may have the following amounts of (R₂O + RO-BaO): less than or equal to 20.0 mol%, less than or equal to 19.0 mol%, less than or equal to 18.0 mol%, less than or equal to 17.0 mol%, less than or equal to 15.0 mol%, less than or equal to 10.0 mol%, less than or equal to 5.0 mol%, less than or equal to 3.0 mol%, less than or equal to 2.0 mol%, or less than or equal to 1.0 mol%. In some further embodiments, the glass composition may have the following amounts of (R₂O+RO-BaO): 0.0 mol% to 20.0 mol%, 0.0 mol% to 17.0 mol%, 0.0 mol% to 5.0 mol%, 1.0 mol% to 20.0 mol%, 1.0 mol% to 5.0 mol%, 2.0 mol% to 18.0 mol%, 2.0 mol% to 15.0 mol%, 3.0 mol% to 20.0 mol%, 3.0 mol% to 18.0 mol%, 3.0 mol% to 1 5.0 mol%, 5.0 mol% to 20.0 mol%, 5.0 mol% to 18.0 mol%, 10.0 mol% to 19.0 mol%, 10.0 mol% to 18.0 mol%, 10.0 mol% to 17.0 mol%, 10.0 mol% to 15.0 mol%, 15.0 mol% to 20.0 mol%, 15.0 mol% to 19.0 mol%, 8.0 mol% to 18.0 mol%, 3.0 mol% to 11.0 mol%, or 8.0 mol% to 18.0 mol%.

[0101] Without being bound by any theory, it was found that improved glass-forming ability was achieved when attempting to melt glass with certain compositions without modifiers, provided that specific relationships were satisfied between the amounts of rare earth metal oxides and several other constituent components. In general, it was found that the total rare earth metal oxide content RE in the unmodified glass was... m O nGlass compositions with a concentration (in mol%) less than the sum of the concentrations (in mol%) of (Nb₂O₅ + ZrO₂) exhibit poor glass-forming properties. For example, these compositions typically tend to have melts that crystallize during cooling at rates less than 300°C / min to 400°C / min, which is generally unacceptable for large-scale production. It is believed that refractory minerals of niobium oxide and / or zirconium oxide precipitate at high temperatures for these compositions. When the composition does not contain modifiers and contains a total rare earth metal oxide content RE m O n When the concentration of (in mol%) is greater than the sum of the concentrations of (Nb₂O₅ + ZrO₂ + SiO₂) (in mol%), these compositions are generally unable to form glass. This is believed to be due to the crystallization of rare earth metal oxides at high temperatures (either naturally or in solid solutions, e.g., with zirconium oxide). When the composition contains no modifier and the amount of SiO₂ is significantly greater than (RE) m O n When the concentration difference (in mol%) of SiO2 (-Nb2O5-ZrO2) is present and the melt does not contain a sufficiently high concentration of titanium dioxide (TiO2), it is found that the glass-forming melt tends to become more susceptible to phase separation or crystallization, or both, at high temperatures. It is believed that SiO2 and TiO2 are likely the driving agents for the phase separation and / or crystallization exhibited by these compositions.

[0102] Therefore, according to some embodiments of this disclosure, the glass composition contains RE m O n The amounts of SiO2, Nb2O5 and ZrO2 satisfy at least one of the following conditions (I) and / or (II), in mol%:

[0103] 0.0≤(SiO2+Nb2O5+ZrO2–RE m O n )≤12.0(I)

[0104] as well as

[0105]

[0106] In some cases, glass compositions with a value less than -1 in Equation (II) are more likely to exhibit good glass-forming ability compared to glass compositions with a numerical range of -1 to 0. It is not intended to limit us to any theory, but it is believed that the glass compositions of this disclosure (both those containing modifiers and those without modifiers) exhibit good glass-forming ability, which may lead to improved solubility of the refractive index enhancer in the glass melt, contributing to improvements in some of the optical properties of the glasses described herein.

[0107] According to embodiments of this disclosure, the glass described herein has a refractive index n greater than or equal to 1.85. d Measured at 587.56 nm. In some examples, the glass has the following refractive index n. d : Greater than or equal to 1.85, greater than or equal to 1.90, greater than or equal to 1.95, greater than or equal to 2.00, greater than or equal to 2.05, or greater than or equal to 2.10, measured at 587.56 nm. In some examples, the glass has the following refractive index n. d 1.85 to 2.10, 1.90 to 2.10, 1.91 to 2.10, 1.95 to 2.10, 2.00 to 2.10, 2.05 to 2.10, 1.85 to 2.05, 1.90 to 2.05, 1.91 to 2.05, 1.95 to 2.05, 2.00 to 2.05, 1.85 to 2.00, 1.90 to 2.00, 1.91 to 2.00, 1.95 to 2.00, 1.85 to 1.95, 1.90 to 1.95, or 1.91 to 1.95, measured at 587.56 nm.

[0108] For a given refractive index, a lower density corresponds to a lighter weight for optical elements using glass. Size and weight are important for many types of optical devices, particularly portable optical devices such as augmented reality systems. As described above, the glass of this disclosure has a combination of high refractive index and low density. According to embodiments of this disclosure, the glass described herein has a density of 5.5 g / cm³. 3 or lower density d RT The measurement was performed at 25°C. In some examples, the glass of this disclosure may have the following density d. RT 5.5g / cm 3 Or even lower, 5.3 g / cm³ 3 Or even lower, 5.1 g / cm³ 3 Or even lower, 4.9 g / cm³ 3 Or even lower, 4.8 g / cm³ 3 Or lower, or 4.5 g / cm³ 3 Or lower, measured at 25°C. In some cases, the glass can have a refractive index n of 1.91 to 2.0. d (Measured at 587.56 nm) and 4.3 g / cm 3 Up to 5.1 g / cm 3 density d RT (Measured at 25°C). In some embodiments, the glass has a refractive index n greater than or equal to 1.90. d (Measured at 587.56 nm) and less than or equal to 4.8 g / cm³ 3 density d RT(Measured at 25°C). In some embodiments, the glass has a refractive index n greater than or equal to 1.96. d (Measured at 587.56 nm) and less than or equal to 4.95 g / cm³ 3 density d RT (Measured at 25°C). In some embodiments, the glass has a refractive index n greater than or equal to 1.91. d (Measured at 587.56 nm) and less than or equal to 5.0 g / cm³ 3 density d RT (Measured at 25°C). In some embodiments, the glass has a refractive index n greater than or equal to 2.00. d (Measured at 587.56 nm) and less than or equal to 5.0 g / cm³ 3 density d RT (Measured at 25℃).

[0109] In some embodiments, the glass of this disclosure can be characterized as having a refractive index n according to the following equation (III). d and density d RT :

[0110] n d –(0.815+0.25*d RT )>0.000(III)

[0111] In the formula, the refractive index n d The measurements were taken at a wavelength of 587.56 nm, and the density was measured at 25°C (unit: g / cm³). 3 In some embodiments, the glass of this disclosure can be characterized as having a refractive index n according to the following equation (IV). d and density d RT :

[0112] n d –(0.850+0.25*d RT >0.000(IV)

[0113] In the formula, the refractive index n d The measurements were taken at a wavelength of 587.56 nm, and the density was measured at 25°C (unit: g / cm³). 3 In some embodiments, the glass of this disclosure may be characterized as having a refractive index n greater than or equal to 0.020 according to Equation (IV). d and density d RT .

[0114] In some embodiments, the glass is characterized as having high transmittance. Generally, the higher the transmittance of the glass, the longer the optical path transmitted for a given optical loss, which can improve optical performance in many applications. High-refractive-index glasses typically contain materials that absorb at least a portion of optical light (e.g., TiO2 and Nb2O5), particularly light in the blue and near-UV regions of the electromagnetic spectrum. In embodiments of this disclosure, the transmittance of the glass can be characterized by different wavelengths in the range of about 300 nm to about 2300 nm. In some applications, high transmittance in the visible and near-UV ranges (blue light region) is particularly desirable. Achieving high transmittance in blue light in high-refractive-index glasses can be challenging. High levels of TiO2 and / or Nb2O5 typically used in glasses to increase the refractive index tend to reduce transmittance in the near-UV region and shift the UV cutoff to higher wavelengths. For the internal transmittance of blue light (considering Fresnel loss), a sample with a thickness of 10 mm is considered acceptable when it has an internal transmittance of 90% or greater at a wavelength of 460 nm; good when it has an internal transmittance of 95% or greater at a wavelength of 460 nm; and excellent when it has an internal transmittance of 97% or greater at a wavelength of 460 nm.

[0115] In some embodiments, the glass may be characterized as having a refractive index n of at least 1.85 that satisfies the following equation (V). d (Measured at 587.56 nm), density d RT (Measured at 25℃) and transmittance index T i :

[0116] n d –(0.815+0.25*d RT )–(0.16–0.38*T i >0.000(V)

[0117] In the formula, the transmittance index T is determined according to the following equation (VI). i :

[0118]

[0119] In the formula, each oxide listed in equation (VI) refers to the amount of oxide in the glass, expressed as mol%. Transmittance index T i It is the fraction of colorless refractive index enhancers (La2O3, Gd2O3, and ZrO2) relative to the sum of the five refractive index enhancers (La2O3, Gd2O3, ZrO2, Nb2O5, and TiO2). T was found... i The value is related to the blue light transmittance of the high-refractive-index, low-density glass disclosed herein.

[0120] In some embodiments, the glass may be characterized as having a refractive index n of at least 1.95 that satisfies the following equation (VII). d (Measured at 587.56 nm), density d RT (Measured at 25℃) and transmittance index T i :

[0121] n d –(0.850+0.25*d RT )–(0.20–0.38*T i >0.000(VII)

[0122] In the formula, the transmittance index T is determined according to equation (VI) above. i .

[0123] Refractive index and density are two properties that can be predicted from the glass composition. Linear regression analysis was performed on comparative example glasses with compositional spaces close to that of this disclosure, as well as some other exemplary glasses, to determine the refractive index n at a wavelength of 587.56 nm. d The compositional correlation and the glass density at 25°C (in g / cm³) 3 The equations predicting the compositional correlation of glass are derived from linear regression analysis. Equations (VIII) and (IX) are obtained and used to predict the refractive index and density of glass, respectively:

[0124]

[0125]

[0126] In the formula, P n The refractive index n of the glass at a wavelength of 587.56 nm is... d The refractive index parameter to be predicted, and P d This refers to the density of glass at 25℃ (in g / cm³). 3 The density parameter used for prediction is based on the glass composition, where each oxide listed in equations (VIII) and (IX) refers to the amount of oxide in the glass, expressed in moles.

[0127] Table 1 below specifies the concentration limits from which equations (VIII) and (IX) are derived. Linear regression analysis used to determine equations (VIII) and (IX) randomly selected glasses as the training dataset for establishing the regressions and selected glasses as the validation dataset to evaluate the interpolation capability within the predefined composition limits (as shown in Table 1 below). A training dataset (approximately 100 glass compositions per property) was randomly selected from literature data available in the publicly available SciGlass glass information database and from exemplary glasses of the embodiments presented herein, satisfying the criteria specified in Table 1 below. Linear regression analysis was used on the datasets specified above to determine equations (VIII) and (IX), excluding irrelevant variables and outliers. Table 2 below presents the resulting equations (VIII) and (IX). Another subset of glass compositions satisfying the same criteria was used as the validation set to evaluate the interpolation capability within the predetermined composition limits, corresponding to the standard deviations specified in Table 2. An external dataset of existing glass compositions (randomly selected from the SciGlass glass information database) was used to evaluate the ability to predict specific properties falling outside the specified compositional limits with reasonable accuracy. This process was iterated multiple times to determine the optimal variables for each property of interest, corresponding to the regression equations specified in Table 2 above.

[0128] Table 1: Component regions used for modeling

[0129]

[0130]

[0131] Table 2: Property Prediction Model

[0132] nature abbreviation unit Prediction parameters Regression equation Standard error 587.56nm refractive index <![CDATA[n d ]]> <![CDATA[P n ]]> Equation (VIII) 0.019 room temperature density <![CDATA[d RT ]]> <![CDATA[g / cm 3 ]]> <![CDATA[P d ]]> Equation (IX) 0.090

[0133] Figure 1 The density d is the result of measurements of some comparative glass (“Comparative Glass”) and exemplary glass (“Example Glass”). RT (Measured at 25℃, unit is g / cm³) 3 ) and density parameter P d A graph showing the functional relationship. For example... Figure 1 The data shows that for most glasses, the density parameter P d The compositional correlation is ±0.090 g / cm³. 3 Error within the range of the measured density. Figure 2 The refractive index n is the measured value of some comparative example glasses (“comparative example glasses”) and exemplary glasses (“example glasses”). d (Measured at 587.56 nm) and refractive index parameter P nA graph showing the functional relationship. For example... Figure 2 The data shows that for most glasses, the refractive index parameter P n The compositional correlation has a measured refractive index n of ±0.019 units. d The error is within the specified range.

[0134] Tables 3-6 below specify concentration limits for some embodiments of this disclosure.

[0135] According to another embodiment of this disclosure, the glass may have a refractive index parameter P that satisfies the following equation (X). n and density parameter P d :

[0136] P n –(0.815+0.25*P d )>0.000 (X)

[0137] According to some embodiments of this disclosure, the glass may have a refractive index parameter P that satisfies the following equation (XI). n and density parameter P d :

[0138] P n –(0.850+0.25*P d )>0.000(XI)

[0139] In some embodiments, the glass of this disclosure may have a refractive index parameter P that satisfies the following equation (XII). n Density parameter P d and transmittance index T i :

[0140] P n –(0.815+0.25*P d )–(0.16–0.38*T i >0.000(XII)

[0141] In the formula, P n The value is 1.85 or greater.

[0142] In some embodiments, the glass of this disclosure may have a refractive index parameter P that satisfies the following equation (XIII). n Density parameter P d and transmittance index T i :

[0143] P n –(0.850+0.25*P d )–(0.20–0.38*Ti )>0.000(XIII)

[0144] In some embodiments, the glass can be characterized by good glass-forming ability, which can be evaluated as resistance to devitrification during the cooling process. As discussed above, glass-forming ability can be numerically measured by determining the critical cooling rate of the melt (i.e., the minimum cooling rate at which the melt forms glass without crystallization). According to one embodiment, the glass can be characterized by a critical cooling rate of less than or equal to 300°C / min, and in some examples less than or equal to 100°C / min. In some embodiments, the glass of this disclosure can be characterized by the ability to cool from 1100°C to 500°C in air within 2.5 minutes without crystallization. Glass characterized by this glass-forming ability is compatible with molding processes.

[0145] Table 3 below shows an exemplary glass A of the present disclosure according to some embodiments of the present disclosure. Table 3 identifies the component combinations and their respective amounts according to some embodiments of the present disclosure. The exemplary glass A in Table 3 may contain additional components according to any aspect of the present disclosure described herein, in amounts not exceeding 0.5 mol%. The exemplary glass A in Table 3 may have a (B2O3 / SiO2) ratio greater than or equal to 0.05, expressed in mol% of each oxide.

[0146] Table 3: Exemplary Glass A

[0147]

[0148]

[0149] Table 4 below shows exemplary glass B of the present disclosure according to some embodiments of the present disclosure. Table 4 identifies the component combinations and their respective amounts according to some embodiments of the present disclosure. The exemplary glass B in Table 4 may contain additional components according to any aspect of the present disclosure described herein, in amounts not exceeding 0.5 mol%. The exemplary glass B in Table 4 may have a (B2O3 / SiO2) ratio greater than or equal to 0.05, expressed in mol% of each oxide.

[0150] Table 4: Exemplary Glass B

[0151] Components Quantity (mol%) <![CDATA[SiO2]]> 14.0 mol% to 50.0 mol% <![CDATA[B2O3]]> 10.0 mol% to 40.0 mol% <![CDATA[TiO2]]> 12.0 mol% to 40.0 mol% <![CDATA[RE m THE n ]]> ≥0.0 mol% <![CDATA[Nb2O5]]> 2.2 mol% to 30.0 mol% <![CDATA[ZrO2]]> 2.5 mol% to 13.0 mol% <![CDATA[Y2O3]]> Basically no Other components 0.0 mol% to 0.5 mol%

[0152] Table 5 below shows exemplary glass C of the present disclosure according to some embodiments of the present disclosure. Table 5 identifies the combinations of components and their respective amounts according to embodiments of the present disclosure. The exemplary glass C in Table 5 may contain additional components according to any aspect of the present disclosure described herein.

[0153] Table 5: Exemplary Glass C

[0154]

[0155]

[0156] The exemplary glass C according to embodiments of this disclosure may also satisfy one or more of the following equations (X) or (XI):

[0157] P n –(0.815+0.25*P d )>0.000(X)

[0158] and / or

[0159] P n –(0.850+0.25*P d )>0.000(XI)

[0160] In the formula, P n It is the refractive index parameter determined according to equation (VIII), and P d It is the density parameter determined according to equation (IX), in which each oxide listed in equations (VIII) and (IX) refers to the amount of oxide in the glass, expressed in mole percent.

[0161] The exemplary glass C according to embodiments of this disclosure may also satisfy one or more of the following equations (III) or (IV):

[0162] n d –(0.815+0.25*d RT )>0.000(III)

[0163] and / or

[0164] n d –(0.850+0.25*d RT >0.000(IV)

[0165] In the formula, d RT The density (in g / cm³) was measured at 25℃. 3 ), and n d The refractive index was measured at 587.56 nm.

[0166] Table 6 below shows exemplary glass D of the present disclosure according to some embodiments of the present disclosure. Table 6 identifies the combinations of components and their respective amounts according to embodiments of the present disclosure. The exemplary glass D in Table 6 may contain additional components according to any aspect of the present disclosure described herein.

[0167] Table 6: Exemplary Glass D

[0168]

[0169] An exemplary glass D according to an embodiment of this disclosure may have a refractive index n greater than or equal to 1.85. d Measured at 587.56 nm. In some embodiments, exemplary glass D satisfies one or more of the following equations (XII) or (XIII):

[0170] P n –(0.815+0.25*P d )–(0.16–0.38*T i >0.000(XII)

[0171] and / or

[0172] P n –(0.850+0.25*P d )–(0.20–0.38*T i )>0.000(XIII)

[0173] In the formula, P n It is calculated based on equation (VIII), P d It was calculated based on equation (IX), and T i It is calculated based on equation (VI).

[0174] The exemplary glass D according to the embodiments of this disclosure may also satisfy one or more of the following equations (V) or (VII):

[0175] n d –(0.815+0.25*d RT )–(0.16–0.38*T i >0.000(V)

[0176] and / or

[0177] n d –(0.850+0.25*d RT )–(0.20–0.38*T i >0.000(VII)

[0178] In the formula, d RT The density (in g / cm³) was measured at 25℃. 3 ), n d The refractive index was measured at 587.56 nm, and T... i It is calculated based on equation (VI).

[0179] Embodiments of this disclosure can provide glass with the following properties: a high refractive index n of 1.90 or higher. d In some embodiments, the concentration is greater than 2.0; the binding concentration is less than or equal to 5.5 g / cm³. 3 The density (measured at 25°C); optionally combined with one or more additional desired characteristics. In some embodiments, the glass of this disclosure can provide a density and refractive index comparable to glass with similar density and refractive index. d The present disclosure describes improved glass forming capabilities compared to some existing borosilicate glasses. These improvements in glass forming capabilities can simplify production, provide cost savings, and / or improve the quality of the final glass product. In some embodiments, the glass of this disclosure can provide improved glass forming capabilities compared to glass with a similar refractive index n. d Blue light transmittance that is comparable to or improved over existing technology glasses in terms of density characteristics.

[0180] Glass transmittance is at least partly based on the compositional components and / or processes used to form the glass. In a manufacturing setting where process parameters have been determined / optimized, the transmittance of the glass becomes substantially composition-dependent. It is not desirable to be limited by any theory that components (e.g., TiO2 and Nb2O5) may reduce the blue light transmittance of the glass, especially when used at high concentrations. However, components (e.g., TiO2 and Nb2O5) can be used to increase the refractive index of the glass without correspondingly and undesirably increasing the glass density. Thus, in some embodiments, components (e.g., TiO2 and Nb2O5) can be added at adaptive concentrations to provide the desired refractive index and density and also to provide glass with an acceptable level of blue light transmittance. Other oxides (e.g., ZrO2, La2O3, Gd2O3, and in some others, other rare earth metal oxides) can also be used to increase the refractive index of the glass described herein. It has been found that adding these oxides can produce glass with the desired blue light transmittance. However, these oxides may also increase density, which is undesirable for some applications. High concentrations of some of these oxides can also reduce the glass-forming ability of the composition. For example, these oxides may increase the liquidus temperature and / or cause crystalline phases containing these oxides to precipitate from the glass melt at high temperatures. Among the oxides ZrO2, La2O3, Gd2O3, and TiO2, ZrO2 has been observed to have the greatest effect on the liquidus temperature in some compositions, while having the least effect on the blue light transmittance of the glass. Therefore, attempts to increase the refractive index and / or decrease the density may have undesirable effects on the glass-forming ability of the composition. Embodiments of this disclosure may provide a glass having a high refractive index n of 1.90 or greater. d In some embodiments, the concentration is greater than 2.0; the binding concentration is less than or equal to 5.5 g / cm³. 3 The density (measured at 25°C) is also provided; at the same time, such glass is provided that exhibits a level of blue light transmittance and glass forming capability that is acceptable for many applications (e.g., augmented reality devices, virtual reality devices, mixed reality devices and / or glasses).

[0181] Example

[0182] The following examples illustrate the various features and advantages provided by this disclosure, and they do not in any way constitute a limitation of the invention or the appended claims.

[0183] Both the exemplary and comparative glasses were prepared by melting relatively pure oxide materials. Table 7 below lists some of the typical undefined elements found in the oxides used in the preparation of the exemplary and comparative glasses described herein.

[0184] Table 7: Oxide Raw Materials and Corresponding Uncertain Element Levels

[0185]

[0186] To prepare glass samples, approximately 15 grams of each sample (target substance content greater than 99.99% by weight) was melted from the batch raw material in a platinum or platinum-rhodium crucible (Pt:Rh = 80:20) at approximately 1300°C for 1 hour. Two controlled cooling conditions were applied. In the first condition (referred to as the “15-minute test”), the sample was cooled from 1100°C to 500°C in the furnace over approximately 15 minutes. In the second condition (referred to as the “2.5-minute test”), the sample was cooled from 1100°C to 500°C in the furnace over approximately 2.5 minutes. Temperature readings were obtained either directly from the furnace temperature or using an IR camera with a calibrated scale. The first condition (15-minute test) approximately corresponds to a cooling rate of up to 300°C / min at a temperature of 1000°C, and the second test condition (2.5-minute test) approximately corresponds to a cooling rate of up to 600°C / min at a temperature of 1000°C (closer to this temperature, the cooling rate is close to its maximum). As the temperature decreases, the cooling rate also decreases significantly. For example... Figure 3 The diagram shows typical configurations for the first and second cooling methods. No chemical analysis was performed on the test samples because similar samples prepared by independent melting were analyzed by XRF (X-ray fluorescence, for all oxides except B2O3) and ICP (inductively coupled plasma mass spectrometry, for B2O3). These analyses yielded deviations of the major components (e.g., Nb2O5) relative to the feed composition within ±2.0 wt%, which corresponds to less than approximately 1 mol%.

[0187] Table 8 below lists the glass composition and properties of exemplary glasses 1-90 according to embodiments of this disclosure. Table 8 includes observations from three devitrification tests (referred to as "Devitrification Test 1", "Devitrification Test 2", and "Devitrification Test 3"). "Devitrification Test 1" relates to the observations of a glass sample molten in a 1-liter crucible under an optical microscope (magnification between 100x and 500x). The following abbreviations "A", "B", "C", and "D" are used to indicate: no crystallization observed ("A"); a very limited number of crystals found under a microscope, typically only one or two spots in the glass, and only at the surface, with more than 98% of the surface being crystal-free ("B"); more crystals at the surface, but more than 90% of the glass surface being crystal-free ("C"); and some crystals in the crucible bulk, with less than 90% of the glass surface being crystal-free ("D"). "Devitrification Test 2" relates to the "15-minute test" cooling protocol described above; "OK" is used to indicate that the glass composition passed this test. "Devitrification Test 3" refers to the "2.5-minute test" cooling protocol described above; "OK" is observed to indicate that the glass composition passed this test.

[0188] Table 8: Exemplary Glass Compositions and Properties

[0189]

[0190]

[0191]

[0192]

[0193] Table 8 (continued)

[0194]

[0195]

[0196]

[0197] Table 8 (continued)

[0198]

[0199]

[0200]

[0201]

[0202] Table 8 (continued)

[0203]

[0204]

[0205]

[0206]

[0207] Table 8 (continued)

[0208]

[0209]

[0210]

[0211] Table 8 (continued)

[0212]

[0213]

[0214]

[0215] Table 8 (continued)

[0216]

[0217]

[0218]

[0219] Table 8 (continued)

[0220]

[0221]

[0222]

[0223]

[0224] Table 8 (continued)

[0225]

[0226]

[0227]

[0228] Table 8 (continued)

[0229]

[0230]

[0231]

[0232] Table 8 (continued)

[0233]

[0234]

[0235]

[0236]

[0237] Table 8 (continued)

[0238]

[0239]

[0240] Table 9 below lists the glass composition and properties of comparative examples 1-25.

[0241] Table 9: Comparative Glass Compositions and Properties

[0242]

[0243]

[0244]

[0245] Table 9 (continued)

[0246]

[0247]

[0248] Table 9 (continued)

[0249]

[0250]

[0251]

[0252] The reference keys for each comparative glass listed in Table 9 are as follows: [1] JP50018509A (OHARA Optical Glass MFG); [2] JPS6033229 (MINOLTA Camera KK); [3] US10287205B2 (CDGM Glass Ltd); [4] US2004220041 (HIKARI Glass Ltd); [5] US7091145B2 (CARL -ZEISS-STIFTUNG Company); [6]US7598193B2 (HOYA Company); [7]US8077406 (HOYA Company); [8]US8207075 (OHARA Ltd); [9]US8661853B2 (HOYA Ltd);

[10] US9169152B2 (CDGM Glass Ltd);

[11] WO2017110304A1.

[0253] Figure 4 The density parameter P of some exemplary glasses and some comparative glasses is shown. d With refractive index P n The relationship diagram is shown. The exemplary glasses (solid circles) are Examples 5, 10, 14, 16 to 21 and 25 to 56 from Table 8. The comparative example glasses (hollow circles) are Examples C1 to C4 from Table 9. The refractive index parameter P for predicting the refractive index at 587.56 nm is determined according to Equation (VIII). n In equation (VIII), the chemical formulas listed refer to the amounts of the corresponding components in the glass, expressed as moles. The density parameter P used to predict room temperature density is determined based on equation (IX). d In the formula, the chemical formulas listed in equation (IX) refer to the amounts of the corresponding components in the glass, expressed in moles. Figure 4 All exemplary and comparative glass examples shown have the characteristics specified in Table 10 below. In Table 10, if applicable, the input "No restrictions" means that it is not considered a restriction when selecting the composition. Figure 4 In this context, some of the components listed above may be labeled for better visibility.

[0254] Table 10: Figure 4 Limitations of the glass composition shown

[0255] quantity unit Minimum value Maximum value <![CDATA[La2O3]]> mole% 13.5 No restrictions <![CDATA[B2O3]]> mole% 1 No restrictions <![CDATA[TiO2]]> mole% 0 35 <![CDATA[P2O5]]> mole% 0 20 <![CDATA[Nb2O5]]> mole% 0 12.5 <![CDATA[GeO2]]> mole% 0 10 <![CDATA[ThO2]]> mole% 0 5 <![CDATA[Al2O3]]> mole% 0 2.5 <![CDATA[SiO2+B2O3]]> mole% 0 50 <![CDATA[ZnO+Y2O3]]> mole% 0 2.5 <![CDATA[B2O3 / (B2O3+SiO2)]]> mole% 0 No restrictions

[0256] The comparative glass examples listed above were selected from known glasses that have the characteristics specified in Table 10, and have a comparable density parameter P. d The highest refractive index parameter P is obtained in the numerical case. n .

[0257] Figure 4 The line shown, corresponding to the equation y = 0.815 + 0.25*x, provides a visual representation of the differences between the comparative example glass with the properties specified in Table 10 and the exemplary glasses 5, 10, 14, 16 to 21 and 25 to 56 according to this disclosure. Figure 4 It can be seen that, Figure 4 The exemplary glass (solid circle) mentioned herein falls above the line y = 0.815 + 0.25*x, and there is no comparative example glass (hollow circle) falling above the line y = 0.815 + 0.25*x, where y corresponds to the refractive index parameter P. n And x corresponds to the density parameter P. d In other words, Figure 4 Some of the exemplary glasses presented satisfy the following equation (X), and there are no comparative example glasses that satisfy the following equation (X):

[0258] P n –(0.815+0.25*P d )>0.000 (X)

[0259] from Figure 4 It can also be seen that, Figure 4 Some of the exemplary glass examples presented fall above the line y = 0.850 + 0.25*x, and there is no comparative example glass falling above the line y = 0.850 + 0.25*x, where y corresponds to the refractive index parameter P. n And x corresponds to the density parameter P. d In other words, Figure 4 The exemplary glass presented herein satisfies the following equation (XI), and no comparative glass satisfies the following equation (XI):

[0260] P n –(0.850+0.25*P d )>0.000 (XI)

[0261] Figure 4 The data shown illustrates that, under the conditions specified in Table 10 above, some exemplary glasses from this disclosure have a comparable density parameter P. d In numerical terms, it has a higher refractive index parameter P compared to the best comparative glass that meets the same conditions. n Numerical values. This can be interpreted as, in prediction, that these exemplary glasses, in the glass described, have a relatively high room temperature density d. RT In numerical cases, it has the highest refractive index n at 587.56 nm. d Numerical value. In other words, in terms of prediction, Figure 4The exemplary glass shown provides a high refractive index n among known glasses having the properties specified in Table 10. d With low density d at room temperature RT An improvement to the combination.

[0262] Figure 5 The room temperature density d of some exemplary glasses and some comparative glasses is shown. RT The refractive index n at 587.56 nm d The relationship diagram is shown. The exemplary glass (solid circle) is Example 25 from Table 8. The comparative glass (hollow circle) is Examples C2 and C5 from Table 9. Figure 5 All exemplary and comparative glass examples shown have the characteristics specified in Table 11. In Table 11, if applicable, the input "No restrictions" means that it is not considered a restriction when selecting the composition. Figure 5 In this context, some of the components listed above may be labeled for better visibility.

[0263] Table 11: Figure 5 Limitations of the glass composition shown

[0264] quantity unit Minimum value Maximum value <![CDATA[La2O3]]> mole% 13.5 No restrictions <![CDATA[B2O3]]> mole% 1 No restrictions <![CDATA[TiO2]]> mole% 0 35 <![CDATA[P2O5]]> mole% 0 20 <![CDATA[Nb2O5]]> mole% 0 12.5 <![CDATA[GeO2]]> mole% 0 10 <![CDATA[ThO2]]> mole% 0 5 <![CDATA[Al2O3]]> mole% 0 2.5 <![CDATA[SiO2+B2O3]]> mole% 0 50 <![CDATA[ZnO+Y2O3]]> mole% 0 2.5 <![CDATA[B2O3 / (B2O3+SiO2)]]> mole% 0 No restrictions

[0265] The comparative glass examples listed above were selected from known glasses that have the characteristics specified in Table 11 mentioned above, and have a comparable density d. RT In numerical cases, it has the highest refractive index n at 587.56 nm. d Measured value.

[0266] Figure 5 The line shown, corresponding to the equation y = 0.815 + 0.25*x, provides a visual representation of the differences between the comparative example glass having the characteristics specified in Table 11 and the exemplary glass 25 according to this disclosure. Figure 5 It can be seen that, Figure 5 The exemplary glass (solid circle) mentioned herein falls above the line y = 0.815 + 0.25*x, and there is no comparative example glass (hollow circle) falling above the line y = 0.815 + 0.25*x, where y corresponds to the refractive index n. d And x corresponds to density d RT In other words, Figure 5 Some of the exemplary glasses presented satisfy the following equation (III), and there are no comparative example glasses that satisfy the following equation (III):

[0267] n d –(0.815+0.25*d RT )>0.000(III)

[0268] from Figure 5 It can also be seen that, Figure 5 Some of the exemplary glass examples presented fall above the line y = 0.850 + 0.25*x, and there is no comparative example glass falling above the line y = 0.850 + 0.25*x, where y corresponds to the refractive index n. d And x corresponds to density d RT In other words, Figure 5 The exemplary glass presented herein satisfies the following equation (IV), and no comparative glass satisfies the following equation (IV):

[0269] n d –(0.850+0.25*d RT >0.000(IV)

[0270] Figure 5 The data shown illustrates that, under the conditions specified in Table 11 above, some exemplary glasses from this disclosure have a comparable density d. RT Measured values ​​(measured at 25℃, unit: g / cm³) 3 In the case of [condition], compared to the best comparative glass that meets the same conditions, it has a higher refractive index n at 587.56 nm. d Measurement values. This can be interpreted as, based on the measured properties, these exemplary glasses, in the glass, at a relatively low d... RT In the case of numerical values, it has the highest n d Numerical value. In other words, in terms of measurement, Figure 5 The exemplary glass shown provides a high refractive index n among known glasses having the properties specified in Table 11. d With low density d at room temperature RT An improvement to the combination.

[0271] Table 12 below presents Figure 4 and 5 Tables 10 and 11 of the comparative example glasses C1 to C5, as well as the numerical values ​​of all properties specified in equations (X), (XI), (III), and (IV), are shown in Table 9. Table 9 presents the complete composition of the comparative example glasses. Table 8 presents the complete composition of the exemplary glasses derived from this disclosure and the properties mentioned above.

[0272] Table 12: Properties of Comparative Glasses Having the Characteristics Specified in Tables 10 and 11

[0273]

[0274]

[0275] Therefore, based on Figure 4 and5 Both predicted and measured property data confirm that some exemplary glasses from this disclosure have a high refractive index n at 587.56 nm, compared to the best comparative example glasses with the properties specified in Tables 10 and 11. d With low density d RT (Measured at 25℃, unit is g / cm³) 3 An improved combination of ).

[0276] Figure 6 The transmittance index T is shown for some exemplary glasses and some comparative glasses. i With the value P n -(0.815+0.25*P d The relationship diagram is shown. The exemplary glasses (solid circles) are Examples 5, 8 to 10, 12, 14 to 21, 25 to 32, 34, 35, 44, 45, 57, 59 to 61, 63 to 73, 75 to 86, and 88 to 90 from Table 8. The comparative example glasses (hollow circles) are Examples C6 to C15 from Table 9. The refractive index parameter P for predicting the refractive index at 587.56 nm is determined according to Equation (VIII). n The density parameter P for predicting room temperature density is determined based on equation (IX). d The transmittance index T is determined according to equation (VI). i . Figure 6 All exemplary and comparative glass examples shown have the characteristics specified in Table 13 below. In Table 13, if applicable, the input "No restrictions" means that selection of the composition is not considered a restriction. Figure 6 In this context, some of the components listed above may be labeled for better visibility.

[0277] Table 13: Figure 6 Limitations of the glass composition shown

[0278]

[0279]

[0280] The comparative glass examples listed above were selected from known glasses that have the characteristics specified in Table 13, and have a comparable transmittance index T. i In numerical cases, it has the highest value P. n -(0.815+0.25*P d ).

[0281] Figure 6The lines corresponding to the equation y = 0.16 - 0.38*x shown provide a visual representation of the differences between comparative example glasses with the properties specified in Table 13 and exemplary glasses 5, 8 to 10, 12, 14 to 21, 25 to 32, 34, 35, 44, 45, 57, 59 to 61, 63 to 73, 75 to 86, and 88 to 90 according to this disclosure. Figure 6 It can be seen that, Figure 6 The exemplary glass (solid circle) mentioned above, as presented in the text, falls above the line y = 0.16 - 0.38 * x, and there is no comparative example glass (hollow circle) falling above the line y = 0.16 - 0.38 * x, where y corresponds to the magnitude P. n -(0.815+0.25*P d x corresponds to the transmittance index T i In other words, Figure 6 Some of the exemplary glasses presented satisfy the following equation (XII), and there are no comparative example glasses that satisfy the following equation (XII):

[0282] P n –(0.815+0.25*Pd)–(0.16–0.38*T i )>0.000 (XII)

[0283] from Figure 6 It can also be seen that, Figure 6 Some of the exemplary glass examples presented are those falling above the line y = 0.20 - 0.38 * x, and there is no comparative example of glass falling above the line y = 0.20 - 0.38 * x, where y corresponds to the magnitude P. n -(0.815+0.25*P d x corresponds to the transmittance index T i In other words, Figure 6 The exemplary glass presented herein satisfies the following equation (XIII), and no comparative glass satisfies the following equation (XIII):

[0284] P n –(0.850+0.25*P d )–(0.20–0.38*T i )>0.000 (XIII)

[0285] This means that, under the conditions specified in Table 13 above, some exemplary glasses from this disclosure have a comparable transmittance index T. i In numerical terms, it has a higher value P compared to the best comparative glass that meets the same conditions. n -(0.815+0.25*P dThis can be interpreted as, predicting, that these exemplary glasses, in the glass described, have a relatively high transmittance index T. i In numerical cases, the quantity with the highest numerical value "n" is... d -(0.815+0.25*d RT In other words, in terms of prediction, Figure 6 The exemplary glass shown provides a transmittance index T in a known glass having the properties specified in Table 13. i With the value "n" d -(0.815+0.25*d RT An improvement in terms of the combination of ")".

[0286] Figure 7 The transmittance index T is shown for some exemplary glasses and some comparative glasses. i With the value "n" d -(0.815+0.25*d RT The relationship diagram is shown below. The exemplary glass (solid circle) is Examples 25, 57 and 61 from Table 8. The comparative glass (hollow circle) is Examples C5, C6, C8, C12 to C14 and C16 to C25 from Table 9. Figure 7 All exemplary and comparative glass examples shown have the characteristics specified in Table 14. In Table 14, if applicable, the input "No restrictions" means that selection of the composition is not considered a restriction. Figure 7 In this context, some of the components listed above may be labeled for better visibility.

[0287] Table 14: Figure 7 Limitations of the glass composition shown

[0288] quantity unit Minimum value Maximum value <![CDATA[B2O3]]> mole% 14 No restrictions <![CDATA[SiO2]]> mole% 2 No restrictions <![CDATA[Nb2O5]]> mole% 1 45 <![CDATA[TiO2]]> mole% 0 36 <![CDATA[ZrO2]]> mole% 0 35 <![CDATA[P2O5]]> mole% 0 20 CaO mole% 0 15 MgO mole% 0 15 <![CDATA[TeO2]]> mole% 0 10 <![CDATA[Li2O]]> mole% 0 8 ZnO mole% 0 5.5 <![CDATA[Ga2O3]]> mole% 0 5 <![CDATA[GeO2]]> mole% 0 3 <![CDATA[MoO3]]> mole% 0 3 <![CDATA[Ta2O5]]> mole% 0 1.5 <![CDATA[Y2O3]]> mole% 0 1 <![CDATA[RE m THE n ]]> mole% 0 50 <![CDATA[R2O]]> mole% 0 18 <![CDATA[RE m O n +TiO2+Nb2O5+ZrO2+Bi2O3+WO3]]> mole% 25 No restrictions <![CDATA[SiO2+B2O3]]> mole% 3 50 <![CDATA[As2O3+Sb2O3]]> mole% 0 1 F atom% 0 0.05 <![CDATA[R2O+RO-BaO]]> mole% 0 20 <![CDATA[n d ]]> 1.85 No restrictions

[0289] The comparative glass examples listed above were selected from known glasses that have the specified characteristics mentioned in Table 14, and have a comparable transmittance index T. i In the case of numerical values, the value "n" has the highest measured value. d -(0.815+0.25*d RT )".

[0290] Figure 7 The line shown, corresponding to the equation y = 0.16 - 0.38*x, provides a visual representation of the differences between the comparative example glass with the characteristics specified in Table 14 and the exemplary glasses 25, 57, and 61 according to this disclosure. Figure 7 It can be seen that, Figure 7The exemplary glass (solid circle) mentioned herein falls above the line y = 0.16 - 0.38 * x, and there is no comparative example glass (hollow circle) falling above the line y = 0.16 - 0.38 * x, where y corresponds to the quantity "n". d -(0.815+0.25*d RT x corresponds to the transmittance index T. i In other words, Figure 7 Some of the exemplary glasses presented satisfy the following equation (V), and there are no comparative example glasses that satisfy the following equation (V):

[0291] n d –(0.815+0.25*d RT )–(0.16–0.38*T i >0.000(V)

[0292] from Figure 7 It can also be seen that, Figure 7 Some exemplary glass examples presented above the line y = 0.20 - 0.38 * x are shown, and there is no comparative example of glass above the line y = 0.20 - 0.38 * x, where y corresponds to the quantity "n". d -(0.815+0.25*d RT x corresponds to the transmittance index T. i In other words, Figure 7 The exemplary glass presented herein satisfies the following equation (VII), and no comparative glass satisfies the following equation (VII):

[0293] n d –(0.850+0.25*d RT )–(0.20–0.38*T i >0.000(VII)

[0294] This means that, under the conditions specified in Table 14 above, some exemplary glasses from this disclosure have a comparable transmittance index T. i In numerical terms, the measured value "n" is higher than that of the best comparative glass that meets the same conditions. d -(0.815+0.25*d RT This can be interpreted as, based on the measured properties, these exemplary glasses have a relatively high transmittance index T in the glass. i In numerical cases, the quantity with the highest numerical value "n" is... d -(0.815+0.25*d RT In other words, based on the properties obtained from the measurement, Figure 7The exemplary glass shown provides a transmittance index T in a known glass having the properties specified in Table 14. i With the value "n" d -(0.815+0.25*d RT An improvement in terms of the combination of ")".

[0295] Table 15 below presents Figure 6 and 7 Tables 13 and 14, showing comparative example glasses C5 to C25, and numerical values ​​for all properties specified in equations (XII), (XIII), (V), and (VII) are included. Table 9 presents the complete composition of the comparative example glasses. Table 8 presents the complete composition of exemplary glasses derived from this disclosure and the properties mentioned above.

[0296] Table 15: Properties of Comparative Glasses Having the Characteristics Specified in Tables 13 and 14

[0297]

[0298]

[0299]

[0300]

[0301] Table 15 (continued)

[0302]

[0303]

[0304]

[0305]

[0306]

[0307] Table 15 (continued)

[0308]

[0309]

[0310]

[0311] Therefore, based on Figure 6 and 7 Both predicted and measured property data confirm that some exemplary glasses from this disclosure have a high refractive index n at 587.56 nm, compared to the best comparative example glasses with the properties specified in Tables 13 and 14.d , room temperature low density d RT and transmittance index T i An improved combination.

[0312] This disclosure includes the following non-limiting aspects. To the extent not described, any feature of aspects 1 through 27 may be combined, in whole or in part, with any one or more features of other aspects of this disclosure to form additional aspects, even if such combinations are not described.

[0313] Many changes and modifications can be made to the embodiments described above in this disclosure without significantly departing from the spirit and principles of this disclosure. All such changes and modifications are intended to be included herein, fall within the scope of this disclosure, and are protected by the appended claims.

[0314] Within the scope not yet described, different features of various aspects of this disclosure may be combined and used as needed. A particular feature not explicitly shown or described in any aspect of this disclosure is not to be construed as being impermissible, but rather as being done for the sake of brevity and conciseness of description. Thus, various features of different aspects may be mixed and matched as needed to form new aspects, whether or not the new aspects are explicitly disclosed.

Claims

1. A type of glass comprising: The SiO2 content ranges from 14.0 mol% to 50.0 mol%. B2O3 is greater than 0.0 mol%. TiO2 ranges from 5.0 mol% to 40.0 mol%. Nb₂O₅ ranges from 2.2 mol% to 50.0 mol%. ZrO2 ranges from 2.5 mol% to 25.0 mol%. Total content of rare earth metal oxides (RE) m O n ) ranging from 0.0 mol% to 30.0 mol%; and Other oxides, when present, are present in amounts of 0.5 mol% or less, and in, The ratio of B₂O₃ to SiO₂ (B₂O₃ / SiO₂), expressed as a mole percent of oxides, is at least 0.

050. Glass contains virtually no Y2O3.

2. The glass as claimed in claim 1, wherein, Glass comprises at least one of the following: TiO2 ranges from 12.0 mol% to 40.0 mol%. ZrO2 ranged from 2.5 mol% to 13.0 mol%; and The Nb₂O₅ content ranged from 2.2 mol% to 30.0 mol%.

3. The glass as claimed in claim 1, wherein, Glass has the following characteristics: Refractive index n from 1.90 to 2.10 d This was measured at a wavelength of 587.56 nm; and 5.5g / cm 3 or even smaller density d RT This was measured at 25℃.

4. The glass as claimed in claim 1, wherein, Based on the amount of each oxide, in mole percent of the oxide, the glass satisfies at least one of the following equations (I) and (II): 0.0≤(SiO2+Nb2O5+ZrO2–RE m O n )≤12.0(I) as well as In the formula, RE m O n It is the total content of rare earth metal oxides, expressed in mol%.

5. The glass as claimed in claim 1, wherein, Glass is characterized by its ability to be cooled from 1100°C to 500°C in air within 2.5 minutes without crystallization.

6. A type of glass comprising: B2O3 ranges from 1.0 mol% to 40.0 mol%. The La2O3 content is 13.5 mol% or more; SiO2 is greater than or equal to 0.0 mol%, of which, The sum of (SiO2+B2O3) is from 1.0 mol% to 50.0 mol%; and The oxide must be selected from at least one of the following: rare earth metal oxides, Al₂O₃, Nb₂O₅, TiO₂, ThO₂, GeO₂, P₂O₅, ZnO, Y₂O₃, BaO, Bi₂O₃, CaO, Er₂O₃, Gd₂O₃, K₂O, La₂O₃, Li₂O, Na₂O, Nd₂O₃, PbO, TeO₂, WO₃, Yb₂O₃, and ZrO₂, provided that: Nb₂O₅ ranges from 0.0 mol% to 12.3 mol%. TiO2 ranges from 0.0 mol% to 33.0 mol%. ThO2 ranges from 0.0 mol% to 5.0 mol%. GeO2 ranges from 0.0 mol% to 10.0 mol%. P2O5 ranges from 0.0 mol% to 20.0 mol%. Al2O3 ranges from 0.0 mol% to 2.5 mol%, and The sum of (ZnO + Y₂O₃) is from 0.0 mol% to 2.5 mol%, and Among them, glass satisfies the following equation (X): P n –(0.815+0.25*P d )>0.000(X) In the formula, P n It is the refractive index parameter of the glass and is calculated according to the following equation (VIII): as well as P d It is a density parameter and is calculated according to the following equation (IX): Furthermore, each oxide listed in equations (VIII) and (IX) refers to the amount of oxide in the glass, expressed in moles.

7. The glass as claimed in claim 6, wherein, The glass includes: B2O3 ranges from 10.0 mol% to 40.0 mol%. The La2O3 content ranged from 13.5 mol% to 30.0 mol%; and The SiO2 content is greater than or equal to 0.0 mol% to 20.0 mol%.

8. The glass as claimed in claim 6, wherein, Glass has the following characteristics: Refractive index n from 1.90 to 2.10 d This was measured at a wavelength of 587.56 nm; and 5.5g / cm 3 or even smaller density d RT This was measured at 25℃.

9. A type of glass comprising: B2O3 is 14.5 mol% or more; The SiO2 content is 2.0 mol% or more, and wherein, The sum of (SiO2+B2O3) is 3.0 mol% to 50.0 mol%. Nb₂O₅ ranges from 1.0 mol% to 45.0 mol%; and The oxide must be selected from at least one of the following: monovalent metal oxides, divalent metal oxides, rare earth metal oxides, As₂O₃, Sb₂O₃, Al₂O₃, TiO₂, MoO₃, Ta₂O₅, GeO₂, P₂O₅, ZnO, Y₂O₃, BaO, Bi₂O₃, CaO, Er₂O₃, Gd₂O₃, Ga₂O₃, K₂O, La₂O₃, Li₂O, Na₂O, Nd₂O₃, PbO, TeO₂, WO₃, Yb₂O₃, and ZrO₂, provided that: TiO2 ranges from 0.0 mol% to 36.0 mol%. ZrO2 is 0.0 mol% or more; Y2O3 ranges from 0.0 mol% to 1.0 mol%. Ta2O5 ranges from 0.0 mol% to 1.5 mol%. GeO2 is 0.0 mol% to 0.5 mol%. The CaO content ranges from 0.0 mol% to 15.0 mol%. P2O5 ranges from 0.0 mol% to 20.0 mol%. Al2O3 ranges from 0.0 mol% to 2.5 mol%. ZnO ranges from 0.0 mol% to 5.5 mol%. MoO3 ranges from 0.0 mol% to 3.0 mol%. MgO ranges from 0.0 mol% to 15.0 mol%. The Ga2O3 content ranges from 0.0 mol% to 5.0 mol%. The Li2O content ranges from 0.0 mol% to 8.0 mol%. TeO2 ranges from 0.0 mol% to 10.0 mol%. The total content of monovalent metal oxides (R2O) ranges from 0.0 mol% to 15.0 mol%. Total content of rare earth metal oxides (RE) m O n The content ranges from 0.0 mol% to 50.0 mol%. The sum of (As2O3+Sb2O3) is 0.0 mol% to 1.0 mol%. (RE m O n The sum of (TiO2+Nb2O5+ZrO2+Bi2O3+WO3) is 25.0 mol% or higher; The sum of (R₂O + RO – BaO) ranges from 0.0 mol% to 20.0 mol%, where RO is the total content of divalent metal oxides; and Glass contains virtually no fluorine, and Among them, glass satisfies the following equation (XII): P n –(0.815+0.25*P d )–(0.16–0.38*T i )>0.000(XII) In the formula, P n It is the refractive index parameter, with a value of 1.85 or greater, and is calculated according to the following equation (VIII): In the formula, P d The density parameter is calculated based on the following equation (IX): as well as In the formula, T i The transmittance index is calculated based on the following equation (VI): Furthermore, each oxide listed in equations (VIII), (IX), and (VI) refers to the amount of oxide in the glass, expressed in moles.

10. The glass as claimed in claim 9, wherein, Glass has the following characteristics: A refractive index n of at least 1.95 d This was measured at a wavelength of 587.56 nm; and the density d was measured at 25°C. RT The unit is g / cm³ 3 ,as well as Among them, glass satisfies the following equation (VII): n d –(0.850+0.25*d RT )–(0.20–0.38*T i )>0.000(VII)。 11. The glass as claimed in claim 9, wherein, The glass includes: The SiO2 content ranges from 2.0 mol% to 36.0 mol%; and B2O3 ranged from 14.5 mol% to 48.0 mol%.

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