Glass material, gradient refractive index glass and manufacturing method thereof

Abstract

The invention relates to a glass material, gradient refractive index glass and a manufacturing method thereof. The gradient refractive index glass comprises the following components in percentage by weight: 38-65% of SiO2; 1.5 to 5 percent of Li2O; 6 to 16 percent of Na2O; 1 to 8 percent of SrO; 2 to 12 percent of B2O3; zrO2: 2 to 10 percent; and Ag2O: 1 * 10 <-4 >-3%. The gradient refractive index glass is provided with the stray light eliminating layer, and the light absorption coefficient of the stray light eliminating layer is large.

Description

Technical Field

[0001] This invention relates to a type of glass, and more particularly to a gradient refractive index glass and a method for manufacturing the same. Background Technology

[0002] Gradient-index glass is a type of glass whose internal refractive index changes continuously in a specific manner, and it has the function of deflecting light trajectories. Gradient-index lenses, made of gradient-index glass, are glass elements mainly used in endoscopes, lens arrays, and other fields. When used as a lens array, the outer cylindrical surface of the gradient-index lens needs to have an anti-stray layer to improve the lens's imaging effect. Gradient-index lens arrays are widely used in scanners, copiers, printers, and other devices. Currently, there are three methods for preparing the anti-stray layer. The first method is to coat the cylindrical surface of the gradient-index lens with optical ink. This method can achieve a good anti-stray layer, but it has disadvantages such as high cost, difficult operation, and a thick ink layer that prevents lenses from being tightly packed. The second method is to immerse the gradient-index lens in a molten salt containing copper ions. This method can also achieve a good anti-stray layer, but the melting point of copper-containing salt is poorly matched with the temperature of conventional ion exchange, and the ion exchange process involves the release of toxic gases, which is detrimental to the environment. The third method involves not preparing a stray light suppression layer on the lens surface, but instead using black epoxy resin to bond the lenses together to create a gradient refractive index lens array. However, due to the volume shrinkage of the resin during curing, this method generally has limited stray light suppression effectiveness and is not suitable for mass production of gradient refractive index lens arrays.

[0003] In the prior art, fabricating gradient refractive index lenses for high-resolution lens arrays presents certain challenges. Patent documents JP2008-230956A, JP2002-211947A, JP2002-121048A, and JP2002-284543A disclose base glasses suitable for fabricating high-resolution gradient refractive index lenses. These glasses all contain a significant amount of TiO2, which is the core component enabling the lens to achieve high imaging resolution. However, TiO2 is a network intermediate component in silicate glasses, and it tends to accumulate at the microscopic level, a typical cause of crystal nucleation in silicate glasses. This leads to a decrease in the glass's resistance to crystallization, impairing the yield of the base glass in the hot-working drawing process. Summary of the Invention

[0004] Based on the above reasons, the technical problem to be solved by the present invention is to provide a gradient refractive index glass with a stray light elimination layer that is suitable for industrial manufacturing and a method for manufacturing the same.

[0005] The technical solution adopted by this invention to solve the technical problem is:

[0006] Gradient-index glass, its composition expressed as a weight percentage, contains: SiO2: 38–65%; Li2O: 1.5–5%; Na2O: 6–16%; SrO: 1–8%; B2O3: 2–12%; ZrO2: 2–10%; Ag2O: 1 × 10⁻⁶. -4 ~3%.

[0007] Furthermore, its components, expressed as a weight percentage, also contain: BaO: 0–10%; and / or K2O: 0–2%; and / or MgO: 0–5%; and / or ZnO: 0–10%; and / or Al2O3: 0–10%; and / or GeO2: 0–2%; and / or TiO2: 0–1%; and / or La2O3: 0–4%; and / or Y2O3: 0–6%; and / or Nb2O5: 0–2%; and / or Sb2O3: 0–0.6%; and / or SnO2: 0–1%.

[0008] Gradient-index glass, its composition expressed as a weight percentage, is as follows: SiO2: 38–65%; Li2O: 1.5–5%; Na2O: 6–16%; SrO: 1–8%; B2O3: 2–12%; ZrO2: 2–10%; Ag2O: 1 × 10⁻⁶. -4 ~3%; BaO: 0~10%; K2O: 0~2%; MgO: 0~5%; ZnO: 0~10%; Al2O3: 0~10%; GeO2: 0~2%; T iO2: 0~1%; La2O3: 0~4%; Y2O3: 0~6%; Nb2O5: 0~2%; Sb2O3: 0~0.6%; SnO2: 0~1%.

[0009] Furthermore, its components are expressed as a weight percentage and satisfy one or more of the following five conditions:

[0010] 1) The ratio of Li2O / (Li2O+Na2O) is 0.15 to 0.30, preferably 0.17 to 0.28, and more preferably 0.19 to 0.26;

[0011] 2) The ratio of (MgO+ZnO) / Na2O is 0.15 to 1.10, preferably 0.25 to 0.90, and more preferably 0.35 to 0.75;

[0012] 3) The ratio of (SrO+BaO) / B2O3 is 0.75 to 2.70, preferably 0.90 to 2.00, and more preferably 1.00 to 1.50;

[0013] 4) The Li2O / ZrO2 ratio is 0.40 to 1.60, preferably 0.55 to 1.0, and more preferably 0.60 to 0.85;

[0014] 5) The ratio of (ZnO+B2O3) / ZrO2 is 1.33 to 4.00, preferably 1.66 to 3.50, and more preferably 2.00 to 3.00.

[0015] Furthermore, its components are expressed as weight percentages, wherein: SiO2: 44–61%, preferably SiO2: 50–57%; and / or Li2O: 1.75–4.5%, preferably Li2O: 2–4%; and / or Na2O: 6.5–15%, preferably Na2O: 7–14%; and / or Ag2O: 1 × 10⁻⁶. -3 ~1%, preferably Ag2O: 0.01~0.5%; and / or SrO: 1.5~7%, preferably SrO: 2~6%; and / or BaO: 1~9%, preferably BaO: 2~8%; and / or B2O3: 3~11%, preferably B2O3: 4~10%; and / or ZrO2: 3~9%, preferably ZrO2: 4~8%; and / or K2O: 0~1%; and / or MgO: 0~4%, preferably MgO: 0.5~3%; and / or ZnO: 0–8%, preferably ZnO: 2–6%; and / or Al2O3: 0–5%; and / or GeO2: 0–0.5%; and / or TiO2: 0–0.5%; and / or La2O3: 0–1%; and / or Y2O3: 0–1.5%; and / or Nb2O5: 0–1%; and / or Sb2O3: 0–0.4%, preferably Sb2O3: 0.1–0.3%; and / or SnO2: 0–0.8%, preferably SnO2: 0–0.6%.

[0016] Furthermore, its components do not contain K2O; and / or Al2O3; and / or GeO2; and / or TiO2; and / or La2O3; and / or Y2O3; and / or Nb2O5; and / or CeO2; and / or CaO; and / or P2O5; and / or Gd2O3; and / or Ta2O5.

[0017] Furthermore, the depth of the stray light elimination layer of the gradient refractive index glass is 0.1–50 μm, preferably 1–40 μm, more preferably 5–30 μm; and / or the average light absorption of the stray light elimination layer at 400–800 nm is higher than 10 cm⁻¹. -1 Preferably, it is higher than 30cm -1 More preferably, it is higher than 50cm -1 .

[0018] The glass material, whose composition is expressed as a weight percentage, contains: SiO2: 38-65%; Li2O: 2-7%; Na2O: 5-12%; SrO: 1-8%; B2O3: 2-12%; ZrO2: 2-10%.

[0019] Furthermore, its components, expressed as a weight percentage, also contain: BaO: 0–10%; and / or K2O: 0–2%; and / or MgO: 0–5%; and / or ZnO: 0–10%; and / or Al2O3: 0–10%; and / or GeO2: 0–2%; and / or TiO2: 0–1%; and / or La2O3: 0–4%; and / or Y2O3: 0–6%; and / or Nb2O5: 0–2%; and / or Sb2O3: 0–0.6%; and / or SnO2: 0–1%.

[0020] The glass material, whose composition is expressed as a weight percentage, consists of SiO2: 38–65%; Li2O: 2–7%; Na2O: 5–12%; SrO: 1–8%; B2O3: 2–12%; ZrO2: 2–10%; BaO: 0–10%; K2O: 0–2%; MgO: 0–5%; ZnO: 0–10%; Al2O3: 0–10%; GeO2: 0–2%; TiO2: 0–1%; La2O3: 0–4%; Y2O3: 0–6%; Nb2O5: 0–2%; Sb2O3: 0–0.6%; SnO2: 0–1%.

[0021] Furthermore, its components are expressed as a weight percentage and satisfy one or more of the following five conditions:

[0022] 1) The ratio of Li2O / (Li2O+Na2O) is 0.20 to 0.45, preferably 0.25 to 0.40, and more preferably 0.30 to 0.36;

[0023] 2) The ratio of (MgO+ZnO) / Na2O is 0.20 to 1.25, preferably 0.30 to 1.00, and more preferably 0.40 to 0.80;

[0024] 3) The ratio of (SrO+BaO) / B2O3 is 0.75 to 2.70, preferably 0.90 to 2.00, and more preferably 1.00 to 1.50;

[0025] 4) The Li2O / ZrO2 ratio is 0.50–1.75, preferably 0.60–1.20, and more preferably 0.70–0.90;

[0026] 5) The ratio of (ZnO+B2O3) / ZrO2 is 1.33 to 4.00, preferably 1.66 to 3.50, and more preferably 2.00 to 3.00.

[0027] Furthermore, its components are expressed as weight percentages, wherein: SiO2: 44–61%, preferably SiO2: 50–57%; and / or Li2O: 2.5–6.5%, preferably Li2O: 3–6%; and / or Na2O: 6–11.5%, preferably Na2O: 7–11%; and / or SrO: 1.5–7%, preferably SrO: 2–6%; and / or BaO: 1–9%, preferably BaO: 2–8%; and / or B2O3: 3–11%, preferably B2O3: 4–10%; and / or ZrO2: 3–9%, preferably ZrO2: 4–8%; and / or Or K2O: 0–1%; and / or MgO: 0–4%, preferably MgO: 0.5–3%; and / or ZnO: 0–8%, preferably ZnO: 2–6%; and / or Al2O3: 0–5%; and / or GeO2: 0–0.5%; and / or TiO2: 0–0.5%; and / or La2O3: 0–1%; and / or Y2O3: 0–1.5%; and / or Nb2O5: 0–1%; and / or Sb2O3: 0–0.4%, preferably Sb2O3: 0.1–0.3%; and / or SnO2: 0–0.8%, preferably SnO2: 0–0.6%.

[0028] Furthermore, its components do not contain K2O; and / or Al2O3; and / or GeO2; and / or TiO2; and / or La2O3; and / or Y2O3; and / or Nb2O5; and / or CeO2; and / or CaO; and / or P2O5; and / or Gd2O3; and / or Ta2O5.

[0029] Furthermore, the refractive index of the glass material is 1.550–1.600, preferably 1.555–1.595, more preferably 1.560–1.590; and / or the Abbe number is 55.00–60.00; and / or the transition temperature is 485°C or higher, preferably 490°C or higher, more preferably 495°C or higher; and / or the water resistance stability is Class 3 or higher, preferably Class 2 or higher; and / or the acid resistance stability is Class 2 or higher, preferably Class 1; and / or the coefficient of thermal expansion α 20-120℃ 60×10-7 / ℃~100×10 -7 / ℃, preferably 65×10 -7 / ℃~95×10 -7 / ℃, more preferably 70×10 -7 / ℃~90×10 -7 / ℃; and / or Young's modulus is 85×10⁻⁶. 9 Pa or higher, preferably 87 × 10 Pa 9 Pa or higher, more preferably 89 × 10 Pa 9 Pa or higher; and / or a Poisson's ratio of 0.230 to 0.250, preferably 0.232 to 0.248, more preferably 0.232 to 0.246; and / or a microkernel hardness of 55 × 10⁻⁶. 9 Pa or higher, preferably 56 × 10 Pa 9 Pa or higher, more preferably 57 × 10 Pa. 9 Pa or above; and / or a density of 2.90 g / cm³ 3 The preferred value is 2.87 g / cm³. 3 The preferred value is 2.84 g / cm³. 3 The following are acceptable conditions: and / or the clarification temperature is 1400°C or below, preferably 1300°C or below, more preferably 1200°C or below; and / or the anti-crystallization performance is Class 3 or above, preferably Class 2 or above, more preferably Class 1.

[0030] The glass preforms are made of the aforementioned glass materials.

[0031] The glass element is made of the glass material described above, or of the glass preform described above.

[0032] Gradient refractive index glass is made from the glass material described above.

[0033] Gradient refractive index lenses are made of the aforementioned gradient refractive index glass.

[0034] The device contains the aforementioned gradient refractive index glass, and / or contains the aforementioned glass material, and / or contains the aforementioned glass element, and / or contains the aforementioned gradient refractive index lens.

[0035] A method for manufacturing gradient refractive index glass, the method comprising the following steps: 1) forming a glass material; 2) drawing the glass material into glass fibers; 3) ion exchange (I); 4) ion exchange (II); 5) heat treatment.

[0036] Furthermore, the ion exchange (I) uses cations containing only Na. +Ion exchange is performed on glass fibers using an ion-rich salt bath. The temperature of ion exchange (I) is 350–550°C, preferably 365–530°C, more preferably 380–510°C, and the time of ion exchange (I) is 1–48 hours, preferably 2–36 hours, more preferably 3–24 hours. Ion exchange (II) uses cations containing Na. + and Ag + Ion exchange is performed in a mixed salt bath for cations, Ag + The ions account for 0.1-20% of the total cations in the salt bath, preferably 0.5-15%, more preferably 1-10%; the temperature of ion exchange (II) is 280-380°C, preferably 290-370°C, more preferably 300-360°C; the time of ion exchange (II) is 0.5-60 minutes, preferably 1-45 minutes, more preferably 2-30 minutes; the temperature of heat treatment is 380-490°C, preferably 390-485°C, more preferably 400-480°C; the treatment time is 0.1-30 hours, preferably 0.2-20 hours, more preferably 0.3-16 hours.

[0037] The beneficial effects of this invention are: the gradient refractive index glass obtained by this invention has a stray light elimination layer, and the light absorption coefficient of the stray light elimination layer is large. The manufacturing method of the gradient refractive index glass of this invention does not generate toxic substances, thus meeting environmental protection requirements.

[0038] In some embodiments, the glass material of the present invention exhibits excellent resistance to crystallization, resulting in a high yield rate when used to manufacture gradient refractive index glasses. Attached Figure Description

[0039] Figure 1 This is an image of a reticle formed by a gradient refractive index lens made of gradient refractive index glass, as described in Example 31.

[0040] Figure 2 This is a photograph of the reticle imaged by a gradient refractive index lens made of gradient refractive index glass, as shown in Comparative Example 1.

[0041] Figure 3 This is a photograph of the reticle imaged by a gradient refractive index lens made of gradient refractive index glass, as shown in Comparative Example 2.

[0042] Figure 4 This is a photograph of the reticle imaged by a gradient refractive index lens made of gradient refractive index glass, as shown in Comparative Example 3.

[0043] Figure 5 This is a side view of the light absorption intensity of the stray light elimination layer of the gradient refractive index glass in Example 32. Detailed Implementation

[0044] The following is a detailed description of the glass material and the embodiments of the gradient refractive index glass of the present invention. However, the present invention is not limited to the embodiments described below, and appropriate modifications can be made to implement it within the scope of the purpose of the present invention. Furthermore, while there are appropriate omissions in the repeated descriptions, this does not limit the spirit of the invention. In the following text, the glass material of the present invention is sometimes simply referred to as glass, and the glass material is a gradient refractive index glass after being processed by processes such as ion exchange and heat treatment.

[0045] [Glass Materials]

[0046] The component (composition) ranges of the glass material of the present invention are described below. In the present invention, unless otherwise specified, the content, total content, and aggregate content of each component are all expressed as weight percentages (wt%), that is, the weight percentage of the content, total content, and aggregate content of each component relative to the total weight of the glass material converted into oxide composition. Here, "converted into oxide composition" refers to the total amount of oxides used as raw materials for the glass material of the present invention, where the oxides, complex salts, and hydroxides decompose and transform into oxides upon melting, and the total amount of such oxides is taken as 100%.

[0047] Unless otherwise specified in the specific context, the numerical ranges listed herein include upper and lower limits. "Above" and "below" include endpoint values ​​and all integers and fractions included within the range, but are not limited to the specific values ​​listed when the range is defined. The term "and / or" as used herein is inclusive; for example, "A and / or B" means either only A, or only B, or both A and B.

[0048] <Essential and Optional Components>

[0049] SiO2 is a glass network forger and an essential component of the glass of this invention. SiO2 can improve the glass's resistance to devitrification and thermal stability. However, if the SiO2 content in the glass is too high, the high-temperature viscosity of the glass will be too high, leading to an increase in the glass refining temperature. Therefore, the SiO2 content is 38-65%, preferably 44-61%, and more preferably 50-57%. In some embodiments, the SiO2 content can be 38%, 38.5%, 39%, 39.5%, 40%, 40.5%, 41%, 41.5%, 42%, 42.5%, 43%, 43.5%, 44%, 44.5%, 45%, 45.5%, 46%, 46.5%, 47%, 47.5%, 48%, 48.5%, 49%, 49.5%, 50%, 50.5%, 51%, 51.5%, 52%, 52.5%, 53%, 53.5%, 54%, 54.5%, 55%, 55.5%, 56%, 56.5%, 57%, 57.5%, 58%, 58.5%, 59%, 59.5%, 60%, 60.5%, 61%, 61.5%, 62%, 62.5%, 63%, 63.5%, 64%, 64.5%, 65%, etc., as well as all ranges and subranges between the above values. It should be understood that, in the implementation plan, any of the above scopes can be combined with any other scopes.

[0050] Li₂O is an essential component of the glass of this invention. During the manufacturing process of gradient refractive index glass, Li₂O is removed from the glass through ion exchange treatment. + Ion replacement with Na + Ions, due to Na + The refractive index contribution of ions is less than that of Li. + Ions, Na on glass surface + The concentration of Na at the center of the glass is greater than that at the center of the glass. +The concentration of Li₂O allows for a refractive index distribution in the glass that is low at the surface and high in the middle, enabling the function of a gradient refractive index lens. In lens array applications, a relatively large light-gathering angle is required. Higher Li₂O content results in a greater refractive index difference formed through ion exchange, leading to a larger light-gathering angle for the gradient refractive index lens. Simultaneously, Li₂O can significantly lower the refining temperature of the glass without significantly affecting its coefficient of thermal expansion, Young's modulus, or hardness. However, excessively high Li₂O content can cause deagglomeration of the glass network, reducing its resistance to crystallization. Therefore, the Li₂O content is 2–7%, preferably 2.5–6.5%, and more preferably 3–6%. In some embodiments, the Li₂O content can be 2%, 2.3%, 2.5%, 2.7%, 3%, 3.3%, 3.5%, 3.7%, 4%, 4.3%, 4.5%, 4.7%, 5%, 5.3%, 5.5%, 5.7%, 6%, 6.3%, 6.5%, 6.7%, 7%, etc., as well as all ranges and subranges between these values. It should be understood that, in the implementation plan, any of the above scopes can be combined with any other scopes.

[0051] Na₂O is an essential component of glass. Through extensive experimental research, the inventors discovered that undesirable factors in the ion exchange process are the main reason for insufficient resolution in gradient refractive index lenses. One such undesirable factor is the influence of the mixed alkali effect in the glass on the ion exchange process. It is necessary to ensure that the diffusion process corresponding to ion exchange has as little influence as possible from the diffusion process caused by the mixed alkali effect. Simultaneously, Na₂O can lower the refining temperature of the glass and increase its coefficient of thermal expansion. However, excessive Na₂O content lowers the glass transition temperature and deteriorates its chemical stability. Therefore, the Na₂O content is 5–12%, preferably 6–11.5%, and more preferably 7–11%. In some embodiments, the Na₂O content can be 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%, 10.5%, 11%, 11.5%, 12%, etc., as well as all ranges and sub-ranges between these values. It should be understood that, in embodiments, any of the above ranges can be combined with any other range.

[0052] Through extensive experimental research, the inventors discovered that in some embodiments, by controlling the Li₂O / (Li₂O+Na₂O) ratio within the range of 0.20 to 0.45, the glass exhibits better water resistance and a lower refining temperature, while the gradient refractive index lens demonstrates better resolution. Therefore, a Li₂O / (Li₂O+Na₂O) ratio of 0.20 to 0.45 is preferred, a Li₂O / (Li₂O+Na₂O) ratio of 0.25 to 0.40 is more preferred, and a Li₂O / (Li₂O+Na₂O) ratio of 0.30 to 0.36 is even more preferred. In some embodiments, Li₂O / (Li₂O+Na₂O) can be 0.20, 0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.27, 0.28, 0.29, 0.30, 0.31, 0.32, 0.33, 0.34, 0.35, 0.36, 0.37, 0.38, 0.39, 0.40, 0.41, 0.42, 0.43, 0.44, 0.45, etc., as well as all ranges and sub-ranges between the above values. It should be understood that, in embodiments, any of the above ranges can be combined with any other range.

[0053] K2O is an external component of the glass network. K2O in glass helps reduce viscosity, simplify glass refining, and increase the coefficient of thermal expansion. However, the glass of this invention has a relatively high alkali metal content; excessive K2O can lead to an excessively high alkali metal content, thereby reducing the glass's resistance to crystallization. Furthermore, K2O can increase uncontrollable factors in the ion exchange process. Therefore, the K2O content is 0-2%, preferably 0-1%, and more preferably no K2O. In some embodiments, the K2O content can be 0%, greater than 0%, 0.01%, 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2%, etc., as well as all ranges and sub-ranges between these values. It should be understood that, in embodiments, any of the above ranges can be combined with any other range.

[0054] MgO is an intermediate component in glass networks. Among divalent metal oxides, MgO has a relatively strong ability to enter the glass network, which is beneficial for improving the chemical stability of the glass. Within a certain range, increasing the MgO content increases the hardness of the glass. However, excessively high MgO content will reduce the glass's resistance to crystallization and lead to a decrease in the content of other divalent metal oxides in the glass, resulting in increased viscosity and decreased refractive index. Therefore, the MgO content is 0–5%, preferably 0–4%, and more preferably 0.5–3%. In some embodiments, the MgO content can be 0%, greater than 0%, 0.01%, 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2%, 2.3%, 2.5%, 2.7%, 3%, 3.3%, 3.5%, 3.7%, 4%, 4.3%, 4.5%, 4.7%, 5%, etc., as well as all ranges and sub-ranges between the above values. It should be understood that, in embodiments, any of the above ranges can be combined with any other range.

[0055] ZnO is an intermediate component in glass networks. Compared to other divalent metal oxides, ZnO has the highest tendency to integrate into glass networks, and its application in high-alkali silicate glass systems is beneficial for reducing the coefficient of thermal expansion of the glass. Simultaneously, ZnO also increases the refractive index of the glass. However, if the ZnO content is too high, the content of network-forming components in the glass will be insufficient, leading to a decrease in the glass's resistance to crystallization. Therefore, the ZnO content is 0–10%, preferably 0–8%, and more preferably 2–6%. In some embodiments, the ZnO content can be 0%, greater than 0%, 0.01%, 0.05%, 0.1%, 0.3%, 0.5%, 0.7%, 1%, 1.3%, 1.5%, 1.7%, 2%, 2.3%, 2.5%, 2.7%, 3%, 3.3%, 3.5%, 3.7%, 4%, 4.3%, 4.5%, 4.7%, 5%, 5.3%, 5.5%, 5.7%, 6%, 6.3%, 6.5%, 6.7%, 7%, 7.3%, 7.5%, 7.7%, 8%, 8.3%, 8.5%, 8.7%, 9%, 9.3%, 9.5%, 9.7%, 10%, etc., as well as all ranges and sub-ranges between the above values. It should be understood that, in embodiments, any of the above ranges can be combined with any other range.

[0056] Through extensive experimental research, the inventors discovered that in some embodiments, controlling the (MgO+ZnO) / Na2O ratio within the range of 0.20 to 1.25 is beneficial for improving the glass's resistance to crystallization, and for giving the glass a higher Young's modulus and a higher transition temperature. Therefore, a (MgO+ZnO) / Na2O ratio of 0.20 to 1.25 is preferred, a ratio of 0.30 to 1.00 is more preferred, and a ratio of 0.40 to 0.80 is even more preferred. In some implementations, (MgO+ZnO) / Na2O can be 0.20, 0.23, 0.25, 0.27, 0.30, 0.33, 0.35, 0.37, 0.40, 0.43, 0.45, 0.47, 0.50, 0.53, 0.55, 0.57, 0.60, 0.63, 0.65, 0.67, 0.70, 0.73, 0.75, 0.77, 0.80, 0.83, 0.85, 0.87, 0.90, 0.93, 0.95, 0.97, 1.00, 1.03, 1.05, 1.07, 1.10, 1.13, 1.15, 1.17, 1.20, 1.23, 1.25, etc., as well as all ranges and subranges between the above values. It should be understood that, in the implementation plan, any of the above scopes can be combined with any other scopes.

[0057] SrO is an intermediate component in the glass network. SrO has a similar effect on increasing the refractive index as ZnO, but its tendency to enter the glass network is relatively lower. Compared to BaO, the presence of SrO in glass is beneficial for improving its chemical stability. At low SrO contents, the glass's acid and water resistance cannot meet the requirements for use. Therefore, the SrO content is 1–8%, preferably 1.5–7%, and more preferably 2–6%. In some embodiments, the SrO content can be 1%, 1.3%, 1.5%, 1.7%, 2%, 2.3%, 2.5%, 2.7%, 3%, 3.3%, 3.5%, 3.7%, 4%, 4.3%, 4.5%, 4.7%, 5%, 5.3%, 5.5%, 5.7%, 6%, 6.3%, 6.5%, 6.7%, 7%, 7.3%, 7.5%, 7.7%, 8%, etc., as well as all ranges and sub-ranges between these values. It should be understood that, in embodiments, any of the above ranges can be combined with any other range.

[0058] BaO increases the refractive index of glass, and an appropriate amount of BaO is beneficial for improving the anti-crystallization properties of the glass of this invention. Compared with MgO and SrO, BaO has a greater impact on the coefficient of thermal expansion of glass; increasing the BaO content increases the coefficient of thermal expansion. However, if the BaO content is too high, the density of the glass increases, and its acid resistance decreases. Therefore, the BaO content is 0–10%, preferably 1–9%, and more preferably 2–8%. In some embodiments, the BaO content can be 0%, greater than 0%, 0.01%, 0.05%, 0.1%, 0.3%, 0.5%, 0.7%, 1%, 1.3%, 1.5%, 1.7%, 2%, 2.3%, 2.5%, 2.7%, 3%, 3.3%, 3.5%, 3.7%, 4%, 4.3%, 4.5%, 4.7%, 5%, 5.3%, 5.5%, 5.7%, 6%, 6.3%, 6.5%, 6.7%, 7%, 7.3%, 7.5%, 7.7%, 8%, 8.3%, 8.5%, 8.7%, 9%, 9.3%, 9.5%, 9.7%, 10%, etc., as well as all ranges and sub-ranges between the above values. It should be understood that, in embodiments, any of the above ranges can be combined with any other range.

[0059] B2O3 is a component of the glass network forging system. In the silicate glass system of the glass of the present invention, the content of B2O3 can be adjusted within a wide range without affecting the good anti-crystallization properties of the glass of the present invention. The content of B2O3 has a significant impact on the diffusion coefficient of the glass of the present invention; as the content of B2O3 increases, the diffusion coefficient of the glass of the present invention decreases. In the case of preparing gradient refractive index lens arrays, since the diameter of the lens is very small, the glass needs to have a relatively low diffusion coefficient, which means that for a low ion exchange diffusion depth, a relatively long time is required to complete the ion exchange, so as to more precisely control the glass ion exchange time. Therefore, the content of B2O3 is 2-12%, preferably 3-11%, and more preferably 4-10%. In some embodiments, the content of B2O3 can be 2%, 2.3%, 2.5%, 2.7%, 3%, 3.3%, 3.5%, 3.7%, 4%, 4.3%, 4.5%, 4.7%, 5%, 5.3%, 5.5%, 5.7%, 6%, 6.3%, 6.5%, 6.7%, 7%, 7.3%, 7.5%, 7.7%, 8%, 8.3%, 8.5%, 8.7%, 9%, 9.3%, 9.5%, 9.7%, 10%, 10.3%, 10.5%, 10.7%, 11%, 11.3%, 11.5%, 11.7%, 12%, etc., as well as all ranges and sub-ranges between the above values. It should be understood that, in embodiments, any of the above ranges can be combined with any other range.

[0060] Through extensive experimental research, the inventors discovered that, in some embodiments, controlling the (SrO+BaO) / B2O3 ratio within the range of 0.75 to 2.70 can improve the chemical stability and hardness of the glass. Therefore, a (SrO+BaO) / B2O3 ratio of 0.75 to 2.70 is preferred, a (SrO+BaO) / B2O3 ratio of 0.90 to 2.00 is more preferred, and a (SrO+BaO) / B2O3 ratio of 1.00 to 1.50 is even more preferred. In some implementations, (SrO+BaO) / B2O3 can be 0.75, 0.80, 0.85, 0.90, 0.95, 1.00, 1.05, 1.10, 1.15, 1.20, 1.25, 1.30, 1.35, 1.40, 1.45, 1.50, 1.55, 1.60, 1.65, 1.70, 1.75, 1.80, 1.85, 1.90, 1.95, 2.00, 2.05, 2.10, 2.15, 2.20, 2.25, 2.30, 2.35, 2.40, 2.45, 2.50, 5.55, 2.60, 2.65, 2.70, etc., as well as all ranges and subranges between the above values. It should be understood that, in the implementation plan, any of the above scopes can be combined with any other scopes.

[0061] Al2O3 is a component of the glass network forging system. In the high-alkali silicate glass system of the present invention, the appropriate amount of Al2O3 does not affect the melting of the glass batch, the rising and removal of bubbles in the molten glass, or lead to a decrease in the glass's anti-crystallization properties. However, the presence of Al2O3 increases the glass diffusion coefficient. The ion diffusion coefficient of the glass can be controlled by adjusting the Al2O3 content, thereby keeping the ion exchange time within a reasonable range. Therefore, the Al2O3 content is 0-10%, preferably 0-5%. In some embodiments, it is generally not necessary for Al2O3 to increase the glass diffusion coefficient; therefore, it is more preferable to have no Al2O3. In some embodiments, the Al2O3 content can be 0%, greater than 0%, 0.01%, 0.05%, 0.1%, 0.3%, 0.5%, 0.7%, 1%, 1.3%, 1.5%, 1.7%, 2%, 2.3%, 2.5%, 2.7%, 3%, 3.3%, 3.5%, 3.7%, 4%, 4.3%, 4.5%, 4.7%, 5%, 5.3%, 5.5%, 5.7%, 6%, 6.3%, 6.5%, 6.7%, 7%, 7.3%, 7.5%, 7.7%, 8%, 8.3%, 8.5%, 8.7%, 9%, 9.3%, 9.5%, 9.7%, 10%, etc., as well as all ranges and sub-ranges between the above values. It should be understood that, in embodiments, any of the above ranges can be combined with any other range.

[0062] GeO2 increases the refractive index of glass, and a small amount of GeO2 does not reduce the glass's resistance to crystallization. However, GeO2 is expensive, and a high content is detrimental to cost control. Therefore, the GeO2 content is 0-2%, preferably 0-0.5%, and more preferably no GeO2. In some embodiments, the GeO2 content can be 0%, greater than 0%, 0.01%, 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2%, etc., as well as all ranges and sub-ranges between the above values. It should be understood that, in embodiments, any of the above ranges can be combined with any other range.

[0063] TiO2 has the effect of increasing the refractive index of glass. Some reports indicate that the presence of TiO2 can significantly improve the imaging resolution of the final graded refractive index lens. However, TiO2 acts as a nucleating agent in silicate glass, easily leading to the formation of crystalline phases such as LiSiO3 and Li2SiO5 in high-alkali glass systems during heat treatment near the softening temperature. In the presence of B2O3 in the glass, these crystalline phases easily cause devitrification. The inventors discovered that the essence of improved imaging resolution lies in reducing the changes in refractive index distribution caused by three types of undesirable factors in the diffusion process (the three undesirable factors being glass ion exchange stress, the mixed alkali effect during ion exchange, and surface relaxation during ion exchange). With reasonable glass composition and subsequent process design, high-resolution graded refractive index lenses can be achieved without the presence of TiO2 in the glass. Therefore, the TiO2 content in the glass of this invention is 0–1%, preferably 0–0.5%, and more preferably no TiO2. In some embodiments, the TiO2 content can be 0%, greater than 0%, 0.01%, 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, etc., as well as all ranges and sub-ranges between the above values. It should be understood that, in embodiments, any of the above ranges can be combined with any other range.

[0064] ZrO2 is an intermediate component in the glass network. In the high-alkali silicate glass system of this invention, ZrO2 generally exists in the form of [ZrO6]. The presence of ZrO2 in the glass is beneficial for increasing its refractive index, water resistance, acid resistance, and weather resistance. Within a certain range, increasing the ZrO2 content is beneficial for improving the glass's hardness. The environment in which the glass undergoes ion exchange in molten salt is harsh. To ensure good surface quality after ion exchange, the glass needs to possess good water resistance, acid resistance, and weather resistance simultaneously; therefore, a certain amount of ZrO2 is required. Furthermore, ZrO2 can increase the glass transition temperature. ZrO2 is a refractory component; excessively high ZrO2 content leads to a slow melting process in the glass batch, requiring extended melting time, resulting in more severe volatilization of alkali metals during glass manufacturing, which is detrimental to maintaining the consistency of the glass composition across different batches. Therefore, the ZrO2 content is 2–10%, preferably 3–9%, and more preferably 4–8%. In some embodiments, the ZrO2 content can be 2%, 2.3%, 2.5%, 2.7%, 3%, 3.3%, 3.5%, 3.7%, 4%, 4.3%, 4.5%, 4.7%, 5%, 5.3%, 5.5%, 5.7%, 6%, 6.3%, 6.5%, 6.7%, 7%, 7.3%, 7.5%, 7.7%, 8%, 8.3%, 8.5%, 8.7%, 9%, 9.3%, 9.5%, 9.7%, 10%, etc., as well as all ranges and sub-ranges between the above values. It should be understood that, in embodiments, any of the above ranges can be combined with any other range.

[0065] Through extensive experimental research, the inventors discovered that in some embodiments, controlling the Li₂O / ZrO₂ ratio within the range of 0.50 to 1.75 is beneficial for improving the glass's production performance and giving it better resistance to crystallization, lower high-temperature viscosity, and higher Young's modulus. Therefore, a Li₂O / ZrO₂ ratio of 0.50 to 1.75 is preferred, 0.60 to 1.20 is more preferred, and 0.70 to 0.90 is even more preferred. In some implementations, the Li₂O / ZrO₂ content can be 0.50, 0.53, 0.55, 0.57, 0.60, 0.63, 0.65, 0.67, 0.70, 0.73, 0.75, 0.77, 0.80, 0.83, 0.85, 0.87, 0.90, 0.93, 0.95, 0.97, 1.00, 1.03, 1.05, 1.07, 1.10, 1... 1.13, 1.15, 1.17, 1.20, 1.23, 1.25, 1.27, 1.30, 1.33, 1.35, 1.37, 1.40, 1.43, 1.45, 1.47, 1.50, 1.53, 1.55, 1.57, 1.60, 1.63, 1.65, 1.67, 1.70, 1.73, 1.75, etc., as well as all ranges and subranges between the above values. It should be understood that, in the implementation scheme, any of the above ranges can be combined with any other range.

[0066] Increasing the ZnO and B2O3 content in glass leads to a decrease in the solubility of ZrO2, making it difficult to improve the intrinsic quality of continuously produced glass and increasing its tendency to crystallize. However, if the ZnO and B2O3 content in glass is too low, the refining temperature of the glass increases. Through extensive experimental research, the inventors discovered that by controlling the (ZnO+B2O3) / ZrO2 ratio within the range of 1.33 to 4.00, the glass can simultaneously possess a lower refining temperature and better anti-crystallization properties. Therefore, a (ZnO+B2O3) / ZrO2 ratio of 1.33 to 4.00 is preferred, a ratio of 1.66 to 3.50 is more preferred, and a ratio of 2.00 to 3.00 is even more preferred. In some implementations, the ratio of (ZnO+B2O3) / ZrO2 can be 1.33, 1.35, 1.37, 1.40, 1.43, 1.45, 1.47, 1.50, 1.53, 1.55, 1.57, 1.60, 1.63, 1.65, 1.67, 1.70, 1.73, 1.75, 1.80, 1.83, 1.85, 1.87, 1.90, 1.93, 1.95, 1.97, 2.00, 2.03, 2.05, 2.07, 2.10, 2.13, 2.15, 2.17, 2.20, 2.23, 2.25, 2.27, 2.30, 2.33, 2.35, 2.37, 2.40, 2.43, 2.45, 2.47, 2.50, 2.53, 2.55, 2.57, 2.60, 2.6 3, 2.65, 2.67, 2.70, 2.73, 2.75, 2.80, 2.83, 2.85, 2.87, 2.90, 2.93, 2.95, 2.97, 3.00, 3.03, 3.05, 3.07, 3.10, 3.13, 3.15, 3.17, 3.20, 3.23, 3.25, 3.27, 3.30, 3.33, 3.35, 3 3.37, 3.40, 3.43, 3.45, 3.47, 3.50, 3.53, 3.55, 3.57, 3.60, 3.63, 3.65, 3.67, 3.70, 3.73, 3.75, 3.80, 3.83, 3.85, 3.87, 3.90, 3.93, 3.95, 3.97, 4.00, etc., as well as all ranges and subranges between the above values. It should be understood that, in the implementation scheme, any of the above ranges can be combined with any other range.

[0067] La2O3 is beneficial for increasing the refractive index of glass, but in high-alkali glass, a high content of La2O3 significantly reduces the glass's resistance to crystallization. Therefore, the La2O3 content is 0-4%, preferably 0-1%, and more preferably no La2O3. In some embodiments, the La2O3 content can be 0%, greater than 0%, 0.01%, 0.05%, 0.1%, 0.3%, 0.5%, 0.7%, 1%, 1.3%, 1.5%, 1.7%, 2%, 2.3%, 2.5%, 2.7%, 3%, 3.3%, 3.5%, 3.7%, 4%, etc., as well as all ranges and sub-ranges between the above values. It should be understood that, in embodiments, any of the above ranges can be combined with any other range.

[0068] Y₂O₃ is beneficial for increasing the refractive index of glass, and a small amount of Y₂O₃ is beneficial for increasing the glass transition temperature. In high-alkali glass, a high content of Y₂O₃ significantly reduces the glass's resistance to crystallization. With the same content, the decrease in glass resistance to crystallization caused by the presence of Y₂O₃ is less than that caused by La₂O₃. Therefore, the Y₂O₃ content is 0–6%, preferably 0–1.5%, and more preferably no Y₂O₃. In some embodiments, the Y₂O₃ content can be 0%, greater than 0%, 0.01%, 0.05%, 0.1%, 0.3%, 0.5%, 0.7%, 1%, 1.3%, 1.5%, 1.7%, 2%, 2.3%, 2.5%, 2.7%, 3%, 3.3%, 3.5%, 3.7%, 4%, 4.3%, 4.5%, 4.7%, 5%, 5.3%, 5.5%, 5.7%, 6%, etc., as well as all ranges and sub-ranges between the above values. It should be understood that, in the implementation plan, any of the above scopes can be combined with any other scopes.

[0069] Nb₂O₅ has the effect of increasing the refractive index of glass; a small amount of Nb₂O₅ can significantly improve the refractive index of the glass of the present invention. However, excessive Nb₂O₅ content will lead to a decrease in the glass's resistance to crystallization. Therefore, the Nb₂O₅ content is 0-2%, preferably 0-1%, and more preferably no Nb₂O₅. In some embodiments, the Nb₂O₅ content can be 0%, greater than 0%, 0.01%, 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2%, etc., as well as all ranges and sub-ranges between the above values. It should be understood that, in embodiments, any of the above ranges can be combined with any other range.

[0070] Sb₂O₃ and SnO₂ act as clarifying agents in glass. In the glass of this invention, selecting Sb₂O₃ or SnO₂, or using both in combination, are both clarifying agent choices that achieve good clarification effects. The higher the content of Sb₂O₃ and SnO₂, the better the clarification effect of the glass. However, if the content of Sb₂O₃ and SnO₂ is further increased, the clarification effect of the glass reaches a certain level and then stops improving, while the glass becomes more corrosive to platinum devices during production. Within a certain range, the content of Sb₂O₃ and SnO₂ can achieve the usable properties of the glass of this invention. Therefore, the Sb₂O₃ content of the glass is 0-0.6%, preferably 0-0.4%, more preferably 0.1-0.3%; the SnO₂ content of the glass is 0-1%, preferably 0-0.8%, more preferably 0-0.6%. The glass of this invention preferably contains one of Sb₂O₃ and SnO₂ as a clarifying agent. In some embodiments, the Sb₂O₃ content can be 0%, greater than 0%, 0.01%, 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, etc., as well as all ranges and sub-ranges between the above values. It should be understood that, in embodiments, any of the above ranges can be combined with any other range. In some embodiments, the SnO₂ content can be 0%, greater than 0%, 0.01%, 0.05%, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, etc., as well as all ranges and sub-ranges between the above values. It should be understood that, in embodiments, any of the above ranges can be combined with any other range.

[0071] <Components not contained>

[0072] CeO2 can be used as a clarifier for glass, but it can also cause severe coloration and is a valuable raw material. Therefore, the glass of this invention preferably does not contain CeO2.

[0073] CaO is an intermediate component in glass networks. The presence of CaO in glass is beneficial for improving its mechanical and processing properties. However, the glass of this invention involves an ion exchange step during the manufacture of gradient refractive index glass. Under prolonged ion exchange, the glass is subject to salt bath corrosion and leaching, which cannot be ignored. The salt bath often contains ions of glass constituent elements. If the salt bath contains CaO... 2+ If ions are present, the ion exchange effect of the salt bath will be significantly reduced, resulting in salt bath poisoning. The presence of CaO in the glass is detrimental to maintaining the glass's high transition temperature, high hardness, and low density while ensuring that the refractive index and Abbe number reach the target range. Therefore, the glass of this invention preferably does not contain CaO.

[0074] P₂O₅ reduces the chemical stability of glass, significantly decreases its resistance to crystallization, and lowers its transition temperature. The presence of P₂O₅ increases the ion diffusion coefficient of the glass, which is detrimental to the precise control of processing time during ion exchange. Therefore, the glass of this invention preferably does not contain P₂O₅.

[0075] The effect of Gd₂O₃ on glass properties is similar to that of La₂O₃ and Y₂O₃, but Gd₂O₃ also has the disadvantage of being expensive and a precious component. Therefore, the glass of this invention preferably does not contain Gd₂O₃.

[0076] Ta₂O₅ can increase the refractive index of glass. However, Ta₂O₅ is a valuable raw material. Therefore, the glass of this invention preferably does not contain Ta₂O₅.

[0077] If Ag₂O is present in the glass material, it can lead to the formation of silver particles and clusters during the glass manufacturing process due to spontaneous reduction, resulting in the glass not being colorless and transparent, and thus rendering it unusable. Therefore, the glass of this invention preferably does not contain Ag₂O.

[0078] Rb₂O, Cs₂O, RuO₂, RhO₂, HfO₂, Sc₂O₃, Yb₂O₃, Ga₂O₃, and In₂O₃ are valuable raw material components, and their presence is foreseeable as not significantly improving the performance of the glass of the present invention. Therefore, the glass of the present invention preferably does not contain Rb₂O, and / or does not contain Cs₂O, and / or does not contain RuO₂, and / or does not contain RhO₂, and / or does not contain HfO₂, and / or does not contain Sc₂O₃, and / or does not contain Yb₂O₃, and / or does not contain Ga₂O₃, and / or does not contain In₂O₃.

[0079] PbO, As₂O₃, Tl₂O, HgO, and CdO are components harmful to human health and the environment. Avoiding the use of these components can reduce environmental pollution during their mining and smelting processes. Therefore, the glass of this invention preferably does not contain PbO, and / or does not contain As₂O₃, and / or does not contain Tl₂O, and / or does not contain HgO, and / or does not contain CdO.

[0080] WO3, V2O5, Cr2O3, MnO2, Fe2O3, CoO, NiO, CuO, Pr2O3, Nd2O3, Pm2O3, Sm2O3, Eu2O3, Tb4O7, Dy2O3, Ho2O3, Er2O3, Tm2O3, Lu2O3, etc. are components that cause glass coloring. Therefore, the glass of the present invention preferably does not contain WO3, and / or does not contain V2O5, and / or does not contain Cr2O3, and / or does not contain MnO2, and / or does not contain Fe2O3, and / or does not contain CoO, and / or does not contain NiO, and / or does not contain CuO, and / or does not contain Pr2O3, and / or does not contain Nd2O3, and / or does not contain Pm2O3, and / or does not contain Sm2O3, and / or does not contain Eu2O3, and / or does not contain Tb4O7, and / or does not contain Dy2O3, and / or does not contain Ho2O3, and / or does not contain Er2O3, and / or does not contain Tm2O3, and / or does not contain Lu2O3.

[0081] The terms "not containing" and "0%" in this invention refer to the fact that the component was not intentionally added to the glass of this invention as a raw material; however, as raw materials and / or equipment for producing glass, there may be some impurities or components that are not intentionally added, which may be present in small or trace amounts in the final glass, and such situations are also within the scope of protection of this patent.

[0082] [Methods for manufacturing glass materials]

[0083] The glass material described in this invention can be prepared using a conventional melting method. Specifically, oxides, hydroxides, fluorides, hydrates, various salts (carbonates, nitrates, sulfates, phosphates, metaphosphates, etc.), boric acid, etc., are used as raw materials. These are thoroughly mixed according to a predetermined ratio of glass components and then placed into a chamber constructed of platinum or refractory material at a set temperature. After a certain period of stirring, bubbling, and settling, the raw materials undergo a solid-state reaction, melting, and homogenization process to form a homogeneous glass melt. The manufacturing temperature of the glass of this invention is within the conventional glass furnace temperature range. Those skilled in the art can determine the melting and homogenization stages of the glass raw materials within the range of 1300–1550°C based on actual conditions. Then, the glass of this invention can be formed into a glass material with any usable shape using single-crucible casting and / or leak forming methods. Those skilled in the art can appropriately select raw materials, process methods, and process parameters according to actual needs. Preferably, the glass material of this invention can be made into strips with a thickness of 25 mm or more, or rods with a diameter of 20 mm or more.

[0084] The glass material of this invention has good forming properties. Based on the content of this invention, those skilled in the art can produce glass with a bubble degree of A or above according to the standard GB / T 7962.8—2010, and a striation degree of C or above according to the standard GB / T 7962.7—2025.

[0085] [Manufacturing methods for gradient refractive index glass]

[0086] The method for manufacturing gradient refractive index glass according to the present invention includes the following steps: 1) forming a glass material; 2) drawing the glass material into glass fibers; 3) ion exchange (I); 4) ion exchange (II); 5) heat treatment. Specifically, it is described below:

[0087] Step 1) Forming the glass material. The formation of the glass material is as described in the above-mentioned "Method for Manufacturing Glass Material", and therefore will not be repeated.

[0088] Step 2) Drawing the glass material into glass wires. The glass material is cold-worked and / or hot-worked into glass rods, or directly formed into glass rods during the manufacturing of the glass material, and then the glass rods are drawn into glass wires using a drawing furnace. In some embodiments, the diameter of the glass wires is 0.1–2.0 mm. In some embodiments, the diameter of the glass wire can be 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm, 0.55mm, 0.6mm, 0.65mm, 0.7mm, 0.75mm, 0.8mm, 0.85mm, 0.9mm, 0.95mm, 1.0mm, 1.05mm, 1.1mm, 1.15mm, 1.2mm, 1.25mm, 1.3mm, 1.35mm, 1.4mm, 1.45mm, 1.5mm, 1.55mm, 1.6mm, 1.65mm, 1.7mm, 1.75mm, 1.8mm, 1.85mm, 1.9mm, 1.95mm, 2.0mm, etc., as well as all ranges and subranges between the above values.

[0089] Step 3) Ion exchange (I).

[0090] Ion exchange (I) uses cations containing only Na + An ion-exchange process is performed on the glass fiber using a salt bath. Those skilled in the art can select the anionic composition of the salt bath (e.g., NaNO3, Na2SO4, etc.). The purpose of this step is to remove Li from the glass. + The ions are partially replaced by Na +Ions form a gradient refractive index within the glass fiber. If the ion exchange (I) temperature is too low, it is difficult to eliminate the stress generated in the glass by the ion exchange process, resulting in a refractive index distribution that is difficult to approach the ideal refractive index distribution. If the ion exchange (I) temperature is too high, the salt bath evaporates too quickly, which is not conducive to maintaining batch-to-batch consistency of gradient refractive index glass. Therefore, the ion exchange (I) temperature is preferably 350–550°C, more preferably 365–530°C, and even more preferably 380–510°C; the ion exchange (I) time is preferably 1–48 hours, more preferably 2–36 hours, and even more preferably 3–24 hours. In some embodiments, the temperature of ion exchange (I) can be 350°C, 355°C, 360°C, 365°C, 370°C, 375°C, 380°C, 385°C, 390°C, 395°C, 400°C, 405°C, 410°C, 415°C, 420°C, 425°C, 430°C, 435°C, 440°C, 445°C, 450°C, 455°C, 460°C, 465°C, 470°C, 475°C, 480°C, 485°C, 490°C, 495°C, 500°C, 505°C, 510°C, 515°C, 520°C, 525°C, 530°C, 535°C, 540°C, 545°C, 550°C, etc., as well as all ranges and subranges between the above values. In some embodiments, the ion exchange (I) time can be 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours, 16 hours, 17 hours, 18 hours, 19 hours, 20 hours, 21 hours, 22 hours, 23 hours, 24 hours, 25 hours, 26 hours, 27 hours, 28 hours, 29 hours, 30 hours, 31 hours, 32 hours, 33 hours, 34 hours, 35 hours, 36 hours, 37 hours, 38 hours, 39 hours, 34 hours, 41 hours, 42 hours, 43 hours, 44 hours, 45 hours, 46 hours, 47 hours, 48 ​​hours, etc., as well as all ranges and subranges between the above values. Those skilled in the art can select appropriate salt bath additives based on the actual salt bath process, salt bath composition, etc.

[0091] Step 4) Ion exchange (II).

[0092] Through extensive experimentation, the inventors discovered that the ion exchange (II) step not only provides the coloring material needed for the stray light elimination layer but also corrects the refractive index at the lens edge. This step is crucial for obtaining a high-resolution gradient refractive index lens with a stray light elimination layer. This is because the aforementioned ion exchange (I) process requires relatively high temperatures to avoid stress hindering the process, but this also leads to structural rearrangement and relaxation on the glass surface. This phenomenon results in an additional decrease in the refractive index of the glass surface, which needs to be compensated for by the ion exchange (II) step. Therefore, the ion exchange (II) step is essential in this method.

[0093] The salt bath used in ion exchange (II) contains cations and Na. + and Ag + Ion exchange is performed using a mixed salt bath for cations. Those skilled in the art can select any available anionic component of the salt bath (such as NaNO3, Na2SO4, AgNO3, AgCl, Ag2SO4, etc.) depending on the specific application of the salt bath. The salt bath contains Ag... + The purpose of ions includes the following two aspects: first, to make Ag... + Ions enter the glass interior through ion exchange, increasing the refractive index of part of the glass surface; secondly, Ag... + Ions enter the glass interior through ion exchange, Ag + The ions are in a metastable state and can form ion clusters during subsequent heat treatment, coloring the glass surface and forming an anti-scattering layer. The salt bath contains Na. + The purpose of ionization is to contain alkali metal ions that are the same as the main components of the glass, and to dilute Ag in the salt bath. + Ion concentration, avoid Ag + The problem of easy decomposition in salt baths due to excessively high concentrations. Specifically, Ag... + The molar percentage of ions in the total cations in the salt bath is 0.1-20%, preferably 0.5-15%, and more preferably 1-10%. In some embodiments, Ag... +The molar percentage of ions in the total cations in the salt bath is 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%, 10.5%, 11%, 11.5%, 12%, 12.5%, 13%, 13.5%, 14%, 14.5%, 15%, 15.5%, 16%, 16.5%, 17%, 17.5%, 18%, 18.5%, 19%, 19.5%, 20%, etc., as well as all ranges and subranges between the above values. Those skilled in the art can select appropriate salt bath additives based on the actual salt bath process and composition.

[0094] The process parameters for ion exchange (II) include ion exchange (II) temperature and ion exchange (II) time.

[0095] The temperature of ion exchange (II) is too high, and it contains Ag. + If the salt bath decomposition rate is too fast, it is detrimental to the stability of the salt bath conditions. If the temperature is too low, the salt bath temperature may approach the salt bath melting point, which can easily cause problems such as salt bath crystallization and turbidity during operation, affecting the consistency of the ion exchange process. The preferred temperature for ion exchange (II) is 280–380°C, more preferably 290–370°C, and even more preferably 300–360°C. In some embodiments, the temperature for ion exchange (II) can be 280°C, 285°C, 290°C, 295°C, 300°C, 305°C, 310°C, 315°C, 320°C, 325°C, 330°C, 335°C, 340°C, 345°C, 350°C, 355°C, 360°C, 365°C, 370°C, 375°C, 380°C, etc., as well as all ranges and sub-ranges between the above values.

[0096] If the ion exchange (II) time is too long, Ag will enter the glass. +The more ions, the better. The inventors have discovered that the ion exchange (II) time has a significant impact on the appearance color and light absorption value of the glass stray light-eliminating layer. The longer the ion exchange (II) time, the darker the color of the glass stray light-eliminating layer, but the thickness of the layer also increases accordingly. If the thickness of the stray light-eliminating layer is too large, its proportion will be too high in applications with small lens diameters, affecting the imaging effect of the lens array. A shorter ion exchange (II) time is less conducive to maintaining batch-to-batch consistency. If the ion exchange (II) time is too short, a stray light-eliminating layer with sufficient usable light absorption capacity cannot be achieved. Therefore, the ion exchange (II) time is preferably 0.5–60 minutes, preferably 1–45 minutes, and more preferably 2–30 minutes. In some embodiments, the ion exchange (II) time can be 0.5 minutes, 1 minute, 2 minutes, 3 minutes, 4 minutes, 5 minutes, 6 minutes, 7 minutes, 8 minutes, 9 minutes, 10 minutes, 15 minutes, 20 minutes, 25 minutes, 30 minutes, 35 minutes, 40 minutes, 45 minutes, 50 minutes, 55 minutes, 60 minutes, etc., as well as all ranges and subranges between the above values.

[0097] Step 5) Heat treatment.

[0098] Heat treatment is a step associated with the aforementioned ion exchange (I) and ion exchange (II). During the heat treatment of glass fibers that have undergone ion exchange (I) and ion exchange (II), on the one hand, the internal Na... + Li + Ag + Ions undergo self-diffusion due to Na + Li + Ag + The radial distribution of ion concentration causes a subtle change in the refractive index distribution. The inventors discovered that Ag... + Although ions are relatively Na + The ions have larger ionic radii, but their self-diffusion during heat treatment is significantly greater than that of Na. + Ions, under appropriate process parameters during heat treatment, can further approximate the ideal imaging refractive index distribution of the lens. On the other hand, Ag on the glass surface... + During heat treatment, ions spontaneously form clusters, creating a stray light elimination layer that absorbs visible light.

[0099] The process parameters for heat treatment include the heat treatment temperature and the heat treatment time. The higher the heat treatment temperature, the better the Ag content. +The larger the size of the ion clusters, the deeper the color and the greater the light absorption of the resulting stray light elimination layer. When the heat treatment temperature exceeds a certain value, a usable stray light elimination layer can be formed. However, excessively high heat treatment temperatures may approach the glass transition temperature. Due to the often undesirable temperature uniformity, glass fiber placement, and internal stress uniformity in actual heat treatment equipment, slightly warping of the glass may occur after heat treatment if the temperature is too high, affecting the accuracy of batch processing. Therefore, the preferred heat treatment temperature is 380–490°C, more preferably 390–485°C, and even more preferably 400–480°C. In some embodiments, the heat treatment temperature can be 380°C, 385°C, 390°C, 395°C, 400°C, 405°C, 410°C, 415°C, 420°C, 425°C, 430°C, 435°C, 440°C, 445°C, 450°C, 455°C, 460°C, 465°C, 470°C, 475°C, 480°C, 485°C, 490°C, etc., as well as all ranges and subranges between the above values.

[0100] The longer the heat treatment time, the greater the degree of self-diffusion in the glass, and the greater the adjustment of the refractive index distribution. In this invention, the heat treatment time is preferably 0.1 to 30 hours, more preferably 0.2 to 20 hours, and even more preferably 0.3 to 16 hours. In some embodiments, the heat treatment time can be 0.1 hours, 0.2 hours, 0.3 hours, 0.4 hours, 0.5 hours, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours, 16 hours, 17 hours, 18 hours, 19 hours, 20 hours, 21 hours, 22 hours, 23 hours, 24 hours, 25 hours, 26 hours, 27 hours, 28 hours, 29 hours, 30 hours, etc., as well as all ranges and sub-ranges between the above values.

[0101] It should be noted that those skilled in the art can also design and perform multiple heat treatments at different temperatures and for different times based on the heat treatment objectives described in this invention, without departing from the spirit and scope of this invention.

[0102] Gradient-index glass

[0103] The gradient refractive index glass of this invention is manufactured using the aforementioned method for producing gradient refractive index glass. It exhibits a gradient of lithium, sodium, and silver mass fractions from its surface inwards, perpendicular to the surface. Specifically, from the surface inwards, within a distance not exceeding half the glass thickness, the lithium mass fraction increases, the silver mass fraction decreases, and the sodium mass fraction either decreases then increases or increases sequentially. Micro-area compositional analysis methods, including but not limited to energy dispersive spectroscopy, wavelength dispersive spectroscopy, X-ray fluorescence, inductively coupled mass spectrometry (ICMMS), and ICM characteristic spectroscopy, can be used to characterize the lithium, sodium, and silver mass fraction gradients in the gradient refractive index glass of this invention. Alternatively, the lithium mass fraction gradient can be inferred from the measured sodium and silver mass fraction gradients by observing the physical principle that the total alkali metal content at any spatial location within the glass during ion exchange follows a certain regularity.

[0104] In this invention, the content, total content, and aggregate content of each component of the gradient refractive index glass are all expressed as weight percentages (wt%). The composition of the gradient refractive index glass can be determined by crushing and grinding the glass into powder and then measuring the composition of the glass powder. The gradient refractive index glass of this invention is made from the glass material of this invention. Except for Li₂O, Na₂O, and Ag₂O, the composition of the gradient refractive index glass is the same as that of the glass material. The specific contents of Li₂O, Na₂O, and Ag₂O are as follows:

[0105] Li₂O is an essential component in gradient refractive index glasses. Although Li₂O is present in the glass material during the ion exchange (I) and ion exchange (II) processes in the manufacture of gradient refractive index glasses... + After leaving the glass and entering the salt bath, the residual Li₂O within the glass is the primary source of the usable gradient refractive index-based light deflection effect. The Li₂O content in the gradient refractive index glass of this invention is 1.5–5%, preferably 1.75–4.5%, more preferably 2–4%. In some embodiments, the Li₂O content can be 1.5%, 1.7%, 2%, 2.3%, 2.5%, 2.7%, 3%, 3.3%, 3.5%, 3.7%, 4%, 4.3%, 4.5%, 4.7%, 5%, etc., and all ranges and sub-ranges between these values. It should be understood that, in embodiments, any of the above ranges can be combined with any other range.

[0106] Na₂O is an essential component in gradient refractive index glasses. Compared to the glass material of the present invention, the gradient refractive index glass contains more Na₂O due to ion exchange (I) and ion exchange (II). The Na₂O content is 6-16%, preferably 6.5-15%, and more preferably 7-14%. In some embodiments, the Na₂O content can be 6%, 6.3%, 6.5%, 6.7%, 7%, 7.3%, 7.5%, 7.7%, 8%, 8.3%, 8.5%, 8.7%, 9%, 9.3%, 9.5%, 9.7%, 10%, 10.3%, 10.5%, 10.7%, 11%, 11.3%, 11.5%, 11.7%, 12%, 12.3%, 12.5%, 12.7%, 13%, 13.3%, 13.5%, 13.7%, 14%, 14.3%, 14.5%, 14.7%, 15%, 15.3%, 15.5%, 15.7%, 16%, etc., as well as all ranges and sub-ranges between the above values. It should be understood that, in embodiments, any of the above ranges can be combined with any other range.

[0107] For gradient refractive index glasses used for imaging purposes, there exists a specific and preferred range for the degree of ion exchange (I), i.e., the degree of sodium substitution for lithium in the gradient refractive index glass is within a specific range. Further, it is preferable that the Li₂O / (Li₂O+Na₂O) ratio is in the range of 0.15 to 0.30, as gradient refractive index lenses made from such glass can exhibit better imaging resolution. Therefore, a Li₂O / (Li₂O+Na₂O) ratio of 0.15 to 0.30 is preferred, more preferably 0.17 to 0.28, and even more preferably 0.19 to 0.26. In some embodiments, Li₂O / (Li₂O+Na₂O) can be 0.15, 0.16, 0.17, 0.18, 0.19, 0.20, 0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.27, 0.28, 0.29, 0.30, etc., as well as all ranges and sub-ranges between the above values. It should be understood that, in embodiments, any of the above ranges can be combined with any other range.

[0108] To ensure that the degree of sodium substitution for lithium is within a specific range, so that the gradient refractive index glass of the present invention obtains the desired stray light reduction layer depth and stray light reduction layer light absorption properties, the preferred ratio of (MgO+ZnO) / Na2O in the gradient refractive index glass of the present invention is 0.15-1.10, more preferably 0.25-0.90, and even more preferably 0.35-0.75; the preferred ratio of Li2O / ZrO2 is 0.40-1.60, more preferably 0.55-1.0, and even more preferably 0.60-0.85. In some implementations, (MgO+ZnO) / Na2O can be 0.15, 0.16, 0.17, 0.18, 0.19, 0.20, 0.23, 0.25, 0.27, 0.30, 0.33, 0.35, 0.37, 0.40, 0.43, 0.45, 0.47, 0.50, 0.53, 0.55, 0.57, 0.60, 0.63, 0.65, 0.67, 0.70, 0.73, 0.75, 0.77, 0.80, 0.83, 0.85, 0.87, 0.90, 0.93, 0.95, 0.97, 1.00, 1.03, 1.05, 1.07, 1.10, etc., as well as all ranges and subranges between the above values. It should be understood that, in the implementation scheme, any of the above ranges can be combined with any other ranges. In some implementation schemes, Li2O / ZrO2 can be 0.40, 0.43, 0.45, 0.47, 0.50, 0.53, 0.55, 0.57, 0.60, 0.63, 0.65, 0.67, 0.70, 0.73, 0.75, 0.77, 0.80, 0.83, 0.85, 0.87, 0.90, 0.93, 0.95, 0.97, 1 0.00, 1.03, 1.05, 1.07, 1.10, 1.13, 1.15, 1.17, 1.20, 1.23, 1.25, 1.27, 1.30, 1.33, 1.35, 1.37, 1.40, 1.43, 1.45, 1.47, 1.50, 1.53, 1.55, 1.57, 1.60, etc., as well as all ranges and subranges between the above values. It should be understood that, in the implementation scheme, any of the above ranges can be combined with any other range.

[0109] Ag₂O is an essential component of gradient refractive index glass. It is primarily found in the stray light suppression layer on the surface of the glass. On one hand, Ag₂O forms a stray light suppression layer with high light absorption intensity after heat treatment. On the other hand, its high refractive index helps compensate for the low refractive index at the edges of the gradient refractive index glass, which leads to poor image quality at the edges of the gradient refractive index lens. However, excessive Ag₂O content necessitates a thicker stray light suppression layer on the glass surface, resulting in excessive light absorption during light transmission through the gradient refractive index lens. Therefore, the Ag₂O content is 1 × 10⁻⁶. -4 ~3%, preferably 1×10 -3 ~1%, more preferably 0.01~0.5%. In some embodiments, the Ag2O content can be 1×10⁻⁶. -4 %, 2×10 -4 %, 3×10 -4 %, 4×10 -4 %, 5×10 -4 %, 6×10 -4 %, 7×10 -4 %, 8×10 -4 %, 9×10 -4 %, 1×10 -3 2×10 -3 3×10 -3 4×10 -3 5×10 -3 6×10 -3 7×10 -3 8×10 -3 9×10 -3 The values ​​are 0.01%, 0.05%, 0.1%, 0.15%, 0.2%, 0.25%, 0.3%, 0.35%, 0.4%, 0.45%, 0.5%, 0.55%, 0.6%, 0.65%, 0.7%, 0.75%, 0.8%, 0.85%, 0.9%, 0.95%, 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2%, 2.1%, 2.2%, 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8%, 2.9%, 3%, etc., as well as all ranges and subranges between the above values. It should be understood that, in the implementation scheme, any of the above ranges can be combined with any other range.

[0110] It should be noted that the contents of Li₂O, Na₂O, and Ag₂O mentioned above are their total contents within the gradient refractive index glass, not their contents on the surface or in a specific area of ​​the glass. Similarly, the ratios of Li₂O / (Li₂O+Na₂O), (MgO+ZnO) / Na₂O, and Li₂O / ZrO₂ mentioned above are their total proportions within the gradient refractive index glass, not their proportions on the surface or in a specific area. Samples for composition testing can be prepared by thoroughly grinding and mixing the gradient refractive index glass into powder, or by dissolving it entirely in a solution.

[0111] In some embodiments, the diameter of the gradient refractive index glass obtained by the present invention is 0.1 to 2.0 mm. In some embodiments, the diameter of the gradient refractive index glass can be 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.55 mm, 0.6 mm, 0.65 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.85 mm, 0.9 mm, 0.95 mm, 1.0 mm, 1.05 mm, 1.1 mm, 1.15 mm, 1.2 mm, 1.25 mm, 1.3 mm, 1.35 mm, 1.4 mm, 1.45 mm, 1.5 mm, 1.55 mm, 1.6 mm, 1.65 mm, 1.7 mm, 1.75 mm, 1.8 mm, 1.85 mm, 1.9 mm, 1.95 mm, 2.0 mm, etc., as well as all ranges and subranges between the above values.

[0112] The performance of the glass material and gradient refractive index glass of the present invention will be described below.

[0113] (a) Properties of glass materials

[0114] <Refractive index and Abbe number>

[0115] The refractive index (n) of glass materials d ) and Abbe number (ν d Test according to the method specified in standard GB / T 7962.1—2010. d n F n C These are the refractive indices of the glass corresponding to wavelengths of 587.6 nm, 480.0 nm, and 656.3 nm, respectively.

[0116] Abbe number (ν) d Defined by the following formula:

[0117]

[0118] A higher refractive index in the glass material is more advantageous for obtaining a larger lens aperture angle. In some embodiments, the refractive index (n) of the glass material of the present invention is... d The refractive index is 1.550 to 1.600, preferably 1.555 to 1.595, and more preferably 1.560 to 1.590. In some embodiments, the refractive index of the glass material can be 1.550, 1.555, 1.560, 1.565, 1.570, 1.575, 1.580, 1.585, 1.590, 1.595, 1.600, etc., as well as all ranges and subranges between the above values.

[0119] In some embodiments, the Abbe number (ν) of the glass material of the present invention d The Abbe number is 55.00 to 60.00. In some embodiments, the Abbe number of the glass material can be 55.00, 55.50, 56.00, 56.50, 57.00, 57.50, 58.00, 58.50, 59.00, 59.50, 60.00, etc., as well as all ranges and subranges between the above values.

[0120] <Transition Temperature>

[0121] Glass transition temperature (T) g Test according to the method specified in standard GB / T 7962.16—2010.

[0122] Since the glass material of this invention is a high-alkali mixed alkali glass, it has a relatively low transition temperature. However, a higher transition temperature is more advantageous for the use of the glass material of this invention. The higher the transition temperature, the wider the process window for achieving a stray light removal layer and adjusting the refractive index distribution during the heat treatment process.

[0123] In some embodiments, the transition temperature (T) of the glass material of the present invention is... g The temperature transition temperature is 485°C or higher, preferably 490°C or higher, and more preferably 495°C or higher. In some embodiments, the transition temperature of the glass material of the present invention can be 485°C, 490°C, 495°C, 500°C, 505°C, 510°C, 515°C, 520°C, 525°C, 530°C, 535°C, 540°C, 545°C, 550°C, etc., as well as all ranges and sub-ranges between the above values.

[0124] <Water Resistance Stability>

[0125] The water resistance stability (R) of glass was tested according to the method described in standard GB / T 17129. W That is, the percentage of leaching of glass with a certain particle size and mass under the action of a specific water environment is tested, and the water resistance stability of the glass is divided into 6 categories according to Table 1 below.

[0126] Table 1.

[0127]

[0128] In some embodiments, the water resistance (R) of the glass material of the present invention is... W It should be of 3 or more categories, preferably 2 or more categories.

[0129] <Acid resistance>

[0130] The acid resistance stability (R) of glass materials was tested according to the method described in standard GB / T 17129. A That is, the percentage of leaching of glass with a certain particle size and mass under the action of a specific acid environment is tested, and the acid resistance stability of the glass is divided into 6 categories according to Table 2 below.

[0131] Table 2.

[0132]

[0133] Salt bath environments are characterized by high temperatures and high ion concentrations. Good acid resistance helps maintain the surface quality of the glass in the salt bath and reduces salt bath degradation caused by the leaching of glass components. The glass material of this invention exhibits good acid resistance. In some embodiments, the acid resistance (R...) of the glass material of this invention... A There are two or more categories, with category 1 being preferred.

[0134] Coefficient of thermal expansion

[0135] The coefficient of thermal expansion of glass materials was tested according to the method specified in standard GB / T 7962.16—2010. The coefficient of thermal expansion of glass materials described in this specification is the average coefficient of thermal expansion (α) of glass in the range of 20–120℃. 20-120℃ ).

[0136] The glass of this invention has a moderate coefficient of thermal expansion, which is beneficial for compatibility with common sealing materials and tubular glass materials. In some embodiments, the coefficient of thermal expansion of the glass material of this invention (α) 20-120℃ ) is 60×10 -7 / ℃~100×10 -7 / ℃, preferably 65×10 -7 / ℃~95×10 -7 / ℃, more preferably 70×10 -7 / ℃~90×10 -7 / ℃. In some embodiments, the coefficient of thermal expansion (α) of the glass material of the present invention is... 20-120℃ ) is 60×10 -7 / ℃, 63×10 -7 / ℃, 65×10-7 / ℃, 67×10 -7 / ℃, 70×10 -7 / ℃, 73×10 -7 / ℃, 75×10 -7 / ℃, 77×10 -7 / ℃, 80×10 -7 / ℃, 83×10 -7 / ℃, 85×10 -7 / ℃, 87×10 -7 / ℃, 90×10 -7 / ℃, 93×10 -7 / ℃, 95×10 -7 / ℃, 97×10 -7 / ℃, 100×10 -7 / ℃, etc., and all ranges and subranges between the above values.

[0137] Young's Modulus

[0138] The Young's modulus (E) of the glass material was tested according to the method described in standard GB / T 7962.6—2010. After the glass sample was kept at a temperature 25°C below the transition temperature for 50 hours, it was cooled at a rate of -2°C / hour for 100 hours and then allowed to cool naturally to room temperature.

[0139] Generally, gradient refractive index lenses used in lens arrays have small diameters and need to be connected into blocks using specific processes before batch polishing to avoid polishing failure caused by bending of unsupported lenses. This requires the glass to have a relatively high Young's modulus to prevent the accumulation of grinding particles on the lens surface during polishing due to a low glass modulus and excessively high polishing speed, resulting in numerous scratches on the edges of the polished lens surface. Compared to other alkali silicate glasses, the glass material of this invention has a relatively high Young's modulus.

[0140] In some embodiments, the Young's modulus (E) of the glass material of the present invention is 85 × 10⁻⁶. 9 Pa or higher, preferably 87 × 10 Pa 9 Pa or higher, more preferably 89 × 10 Pa 9 Pa or higher. In some embodiments, the Young's modulus of the glass material of the present invention is 85 × 10⁻⁶. 9 Pa, 85.5 × 10 9 Pa, 86×10 9 Pa, 86.5 × 10 9 Pa, 87×10 9 Pa, 87.5 × 10 9 Pa, 88×10 9 Pa, 88.5×109 Pa, 89×10 9 Pa, 89.5 × 10 9 Pa, 90×10 9 Pa, 90.5 × 10 9 Pa, 91×10 9 Pa, 91.5 × 10 9 Pa, 92×10 9 Pa, etc., and all ranges and subranges between the above values.

[0141] Poisson's ratio

[0142] The Poisson's ratio of the glass was tested according to the method described in the standard GB / T 7962.6—2010.

[0143] The glass material of the present invention has a relatively suitable Poisson's ratio. In some embodiments, the Poisson's ratio of the glass material of the present invention is 0.230 to 0.250, preferably 0.232 to 0.248, and more preferably 0.232 to 0.246. In some embodiments, the Poisson's ratio of the glass material of the present invention can be 0.230, 0.231, 0.232, 0.233, 0.234, 0.235, 0.236, 0.237, 0.238, 0.239, 0.240, 0.241, 0.242, 0.243, 0.244, 0.245, 0.246, 0.247, 0.248, 0.249, 0.250, etc., as well as all ranges and subranges between the above values.

[0144] <Micro Kelvin Hardness>

[0145] Glass material was processed into 40×30×10 mm samples with two polished surfaces. The samples were held at a temperature 25°C below their transformation temperature for 50 hours, then cooled at a rate of -2°C / hour for 100 hours, and finally allowed to cool naturally to room temperature. The micro-Kirch hardness (hereinafter referred to as hardness) of the glass was tested using a microhardness tester and a standard Kirchhoff hardness indenter, specifically a pyramidal diamond indenter with an α angle of 172.5° and a β angle of 130° between its two top edges. The force was applied for 10 seconds, and the corresponding weight was 200g. The micro-Kirch hardness (H) of the glass was calculated using the following formula. K ):

[0146]

[0147] Where F is the magnitude of the test force and d is the length of the diagonal of the indentation.

[0148] In applications involving lens arrays, the glass should have high hardness to mitigate surface quality degradation under conditions such as vibration and friction.

[0149] In some embodiments, the micro Kirkhardness of the glass material of the present invention is 55 × 10⁻⁶. 9 Pa or higher, preferably 56 × 10 Pa 9 Pa or higher, more preferably 57 × 10 Pa. 9 Pa or higher. In some embodiments, the micro Kirkwald hardness of the glass material of the present invention is 55 × 10⁻⁶. 9 Pa, 55.3 × 10 9 Pa, 55.5 × 10 9 Pa, 55.7 × 10 9 Pa, 56×10 9 Pa, 56.3 × 10 9 Pa, 56.5 × 10 9 Pa, 56.7 × 10 9 Pa, 57×10 9 Pa, 57.3 × 10 9 Pa, 57.5 × 10 9 Pa, 57.7 × 10 9 Pa, 58×10 9 Pa, etc., and all ranges and subranges between the above values.

[0150] <Density>

[0151] The density of glass materials was tested according to the method specified in the standard GB / T7962.20—2010.

[0152] In some embodiments, the density (ρ) of the glass material of the present invention is 2.90 g / cm³. 3 The preferred value is 2.87 g / cm³. 3 The preferred value is 2.84 g / cm³. 3 In some embodiments, the density of the glass material of the present invention can be 2.75 g / cm³. 3 2.76 g / cm 3 2.77 g / cm 3 2.78g / cm 3 2.79 g / cm 3 2.80g / cm 3 2.81 g / cm 3 2.82 g / cm 3 2.83 g / cm 3 2.84 g / cm 3 2.85g / cm 3 2.86 g / cm 3 2.87 g / cm 3 2.88g / cm3 2.89 g / cm 3 2.90g / cm 3 And so on, as well as all ranges and subranges between the above values.

[0153] <Clarification Temperature>

[0154] In this invention, the temperature corresponding to a glass viscosity of 100 poise is defined as the glass refining temperature. A lower glass refining temperature is beneficial for reducing energy consumption during glass production, minimizing refractory waste and dust generated from the volatilization of glass components, and extending the lifespan of platinum equipment on the production line, thus possessing greater economic and social value. The high-temperature viscosity curve of the glass is tested using the rotor viscometer method described in the standard ASTM C965-1996R2017. The glass material of this invention, in addition to possessing good Young's modulus and chemical stability, also exhibits a relatively low refining temperature.

[0155] In some embodiments, the refining temperature (T) of the glass material of the present invention is... f The refining temperature is below 1400℃, preferably below 1300℃, and more preferably below 1200℃. In some embodiments, the refining temperature of the glass material of the present invention can be 1100℃, 1110℃, 1120℃, 1130℃, 1140℃, 1150℃, 1160℃, 1170℃, 1180℃, 1190℃, 1200℃, 1210℃, 1220℃, 1230℃, 1240℃, 1250℃, 1260℃, 1270℃, 1280℃, 1290℃, 1300℃, 1310℃, 1320℃, 1330℃, 1340℃, 1350℃, 1360℃, 1370℃, 1380℃, 1390℃, 1400℃, etc., as well as all ranges and sub-ranges between the above values.

[0156] Anti-crystallization properties

[0157] The glass material of this invention was cut into glass blocks of 20×20×10 mm in size, washed with deionized water, and then placed in a test furnace at 900°C for a specific time before being removed and their surface and internal condition observed. The anti-crystallization performance of the glass was rated using the method described in Table 3.

[0158] Table 3.

[0159]

[0160] During the glass drawing process, the thermal processes experienced by the glass in the drawing furnace may differ. For example, the glass near the glass container interface of the drawing furnace flows relatively slower than the glass in the middle of the container, and it holds at high temperatures for a longer time. If the glass does not possess good resistance to crystallization, it is easy for defects to appear on the surface and inside of the glass wire prepared using the glass rod and the drawing furnace. Because the diameter of the glass wire is very thin, these defects are difficult to detect, amplifying the severity of problems caused by poor resistance to crystallization.

[0161] In some embodiments, the glass material of the present invention exhibits an anti-crystallization performance of class 3 or higher, preferably class 2 or higher, and more preferably class 1. The glass material of the present invention possesses good anti-crystallization performance.

[0162] (II) Properties of Gradient Refractive Index Glass

[0163] <Depth of stray light elimination layer>

[0164] The depth of the stray light elimination layer was indirectly determined using energy dispersive spectroscopy (EDS). Glass material was cold-processed into 40×30×2mm glass slides with two polished surfaces, or drawn into glass wires of a specific diameter. Following set process parameters, ion exchange (I), ion exchange (II), and heat treatment were performed, and samples with polished cross-sections were then cold-processed. After gold sputtering onto the sample cross-section, the silver ion depth on the glass surface was measured using an EDS attachment of a scanning electron microscope. Generally, samples prepared using the above method exhibit a gradual decrease in silver ion concentration from the surface to the interior, and silver ion clusters are the main source of the stray light elimination layer in the gradient refractive index glass of this invention. Therefore, the depth at which the silver ion concentration decreases to 10% of the surface silver ion concentration is defined as the depth of the stray light elimination layer, denoted as D. Ag .

[0165] Given a fixed stray light reduction layer effect, the layer should have the smallest possible thickness to avoid affecting the internal transmission light path of the gradient refractive index glass. However, the stray light reduction layer preparation method described in this invention is essentially a diffusion process, therefore it cannot obtain a stray light reduction layer below a specific depth. By selecting an appropriate process, a lower stray light reduction layer depth can be obtained.

[0166] In some embodiments, the depth of the stray light elimination layer (D) of the gradient refractive index glass of the present invention is... AgThe depth of the anti-stray layer of the gradient refractive index glass of the present invention is 0.1–50 μm, preferably 1–40 μm, and more preferably 5–30 μm. In some embodiments, the depth of the anti-stray layer of the gradient refractive index glass of the present invention can be 0.1 μm, 0.5 μm, 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 13 μm, 15 μm, 17 μm, 20 μm, 23 μm, 25 μm, 27 μm, 30 μm, 33 μm, 35 μm, 37 μm, 40 μm, 43 μm, 45 μm, 47 μm, 50 μm, etc., as well as all ranges and sub-ranges between the above values.

[0167] <Stray light absorption layer>

[0168] The light absorption of the stray light elimination layer was determined using a comparative spectral method. Two large polished glass sheets (40×30×2mm) were processed. After undergoing ion exchange (I), ion exchange (II), and heat treatment processes according to set parameters, the transmission spectra were measured using a UV-Vis spectrophotometer. The average transmittance in the 400-800nm ​​range was denoted as T1, and the corresponding average light absorption in the 400-800nm ​​range was denoted as α1. The transmission spectra were then compared with those of a polished glass sheet of the same thickness that had not undergone ion exchange (I), ion exchange (II), and heat treatment processes. The average transmittance in the 400-800nm ​​range was denoted as T2, and the corresponding average light absorption in the 400-800nm ​​range was denoted as α2. The average light absorption in the 400-800nm ​​range of the stray light elimination layer was defined as α3.

[0169]

[0170] That is, the light absorption of the stray light elimination layer is estimated by comparing the changes in glass spectrum before and after ion exchange (I), ion exchange (II), and heat treatment processes, as well as by measuring the thickness of the stray light elimination layer.

[0171] In some embodiments, the average light absorption (α3) of the anti-stray light layer of the gradient refractive index glass of the present invention at 400-800 nm is higher than 10 cm⁻¹. -1 Preferably, it is higher than 30cm -1 More preferably, it is higher than 50cm -1 In some embodiments, the average light absorption of the anti-stray layer of the gradient refractive index glass of the present invention at 400-800 nm can be higher than 10 cm⁻¹. -1 11cm -1 15cm -1 20cm -1 25cm -1 30cm -1 35cm -1 40cm -1 45cm -150cm -1 55cm -1 60cm -1 65cm -1 70cm -1 75cm -1 80cm -1 85cm -1 90cm -1 95cm -1 100cm -1 And so on, as well as all ranges and subranges between the above values.

[0172] <Sidelight reduction layer color>

[0173] The glass material was processed into two large polished glass sheets, each 40×30×2mm. After undergoing ion exchange (I), ion exchange (II), and heat treatment processes according to set parameters, the color of the stray light elimination layer was determined by visual observation. Under incandescent light, the color was observed perpendicularly to the large surface of the sample, and the results were recorded. The possible colors of the observed stray light elimination layer, arranged from lightest to darkest, include colorless transparent, weak gray, pale yellow, yellow, yellowish-brown, red, and dark red.

[0174] In some embodiments, the color of the stray light elimination layer of the gradient refractive index glass of the present invention is yellow or darker, preferably yellowish-brown or darker, and more preferably dark red.

[0175] <Lens Resolution Test>

[0176] A gradient refractive index glass was fabricated into a gradient refractive index lens with an intercept of 0.6P, meaning that the path of a sinusoidal ray in the lens is 0.6 times the period of the sine wave. The lens was placed on a reticle, and the image formed by the lens on the reticle was observed using an optical microscope. The results were recorded using a camera.

[0177] [Glass prefabrication and glass components]

[0178] Glass preforms can be manufactured from the produced glass material using methods such as grinding, hot pressing, or precision stamping. Specifically, glass preforms can be manufactured by machining the glass material of this invention, such as grinding and polishing; or by making a preform from the glass material for molding, then hot pressing and grinding the preform; or by precision stamping a preform made through grinding. It should be noted that the means of preparing glass preforms are not limited to the methods described above.

[0179] Both the glass preform and the glass element of the present invention are formed from the glass material described above. The glass preform of the present invention possesses the excellent properties of the glass material; the glass element of the present invention possesses the excellent properties of the glass material, and can provide various high-value glass elements such as lenses and prisms. Examples of lenses include concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, plano-concave lenses, and other lenses with spherical or aspherical lens surfaces.

[0180] Gradient-index lenses

[0181] The glass material of this invention is manufactured into gradient refractive index glass using the method described in this invention. Then, it is processed into cylindrical glass fibers of a specific length through cold working processes such as cutting and double-sided polishing, thus obtaining a gradient refractive index lens. In some embodiments, the diameter of the gradient refractive index lens obtained by this invention is 0.1–2.0 mm. In some embodiments, the diameter of the gradient refractive index lens can be 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, 0.5 mm, 0.55 mm, 0.6 mm, 0.65 mm, 0.7 mm, 0.75 mm, 0.8 mm, 0.85 mm, 0.9 mm, 0.95 mm, 1.0 mm, 1.05 mm, 1.1 mm, 1.15 mm, 1.2 mm, 1.25 mm, 1.3 mm, 1.35 mm, 1.4 mm, 1.45 mm, 1.5 mm, 1.55 mm, 1.6 mm, 1.65 mm, 1.7 mm, 1.75 mm, 1.8 mm, 1.85 mm, 1.9 mm, 1.95 mm, 2.0 mm, etc., as well as all ranges and subranges between the above values.

[0182] [equipment]

[0183] The glass materials or glass elements of this invention can be used to manufacture devices such as photographic equipment, video recording equipment, display equipment, and monitoring equipment. The glass materials or glass elements of this invention are suitable for use in automotive lighting instruments and optical equipment, and can be applied in fields such as automotive. The glass materials or glass elements of this invention are suitable for use in devices such as micro-projection, micro-imaging (video / photography), and micro-lighting. The gradient refractive index glass or gradient refractive index lens of this invention can be used to manufacture devices such as scanners, copiers, printers, and endoscopes.

[0184] Example

[0185] <Examples of Glass Materials>

[0186] To further illustrate and explain the technical solution of the present invention, the following non-limiting embodiments are provided.

[0187] In this embodiment, glass materials with the compositions shown in Tables 4 to 8 were obtained using the glass material manufacturing method described above. Furthermore, the properties of each glass were measured using the testing method described in this invention, and the measurement results are shown in Tables 4 to 8.

[0188] Table 4.

[0189]

[0190] Table 5.

[0191]

[0192] Table 6.

[0193]

[0194] Table 7.

[0195]

[0196] Table 8.

[0197]

[0198] <Example of Gradient Refractive Index Glass>

[0199] To further illustrate and explain the technical solution of the present invention, the following non-limiting embodiments and comparative examples are provided.

[0200] In this embodiment, the glass materials from the above-described glass material embodiments were manufactured into gradient refractive index glasses using the aforementioned method for manufacturing gradient refractive index glasses, and the results are shown in Tables 9 and 10. Furthermore, the characteristics of each gradient refractive index glass were measured using the testing method described in this invention, and the measurement results are shown in Tables 9 and 10. Comparative examples were obtained by using the partial gradient refractive index glass manufacturing method steps for some of the glass materials from the above-described glass material embodiments, and these are shown in Tables 10 and 11.

[0201] Table 9.

[0202]

[0203] Table 10.

[0204]

[0205] Table 11.

[0206]

[0207] The image formed by the gradient refractive index lens made of gradient refractive index glass in Example 31 on the reticle is as follows: Figure 1As shown, the lens has good imaging resolution.

[0208] Comparative Example 1 used the same glass material composition as Example 31 to fabricate a gradient refractive index glass and then fabricated a gradient refractive index lens. The lens diameter, ion exchange (I) process temperature, and process time were kept consistent, but the ion exchange (II) and heat treatment processes were not performed. The lens obtained after cold processing was colorless and transparent, and no stray light elimination layer was observed. Meanwhile, the resolution photograph of the lens is as follows... Figure 2 As shown, the imaging resolution in the central area is acceptable, but the imaging at the edges is blurry.

[0209] Comparative Example 2 used the same glass material composition as Example 34 to fabricate a gradient refractive index glass, and fabricated a gradient refractive index lens. The lens diameter, ion exchange (I) process temperature and time, and ion exchange (II) process temperature and time were kept consistent, but no heat treatment process was performed. After cold processing, the lens appeared light gray and transparent. Energy dispersive spectroscopy (EDS) analysis showed that its stray light elimination layer depth was 5 μm, and the average light absorption of this layer in the 400-800 nm range was only 1.57 cm⁻¹. -1 Meanwhile, the resolution of the lens in the photograph is as follows: Figure 3 As shown, the edge portion of the image is blurred, similar to the case in Comparative Example 1.

[0210] Comparative Example 3 used the same glass material composition as Example 31 to fabricate a gradient refractive index glass, and fabricated a gradient refractive index lens. The lens diameter, ion exchange (I) process temperature and time, and heat treatment steps were kept consistent, but the ion exchange (II) step was not performed. The lens obtained after cold processing was colorless and transparent. Meanwhile, the resolution photograph of the lens was as shown... Figure 4 As shown, its imaging effect is somewhat different from that of Comparative Example 1, but it still has a relatively poor imaging resolution compared to Example 31.

[0211] Comparative Examples 4-8 used the same glass material composition as Example 35 to fabricate gradient refractive index glasses and gradient refractive index lenses with the same lens diameter, but without ion exchange (II) or heat treatment processes. Comparative Examples 4-8 employed a series of different ion exchange (I) process parameters. The ion exchange (I) time for Comparative Examples 4-5 was shorter than that for Example 35, the ion exchange (I) time for Comparative Example 6 was the same as that for Example 35, and the ion exchange (I) time for Comparative Examples 7-8 was longer than that for Example 35. However, none of Comparative Examples 4-8 yielded gradient refractive index lenses with good imaging resolution.

[0212] Example 32: The light absorption intensity of the stray light elimination layer is as follows Figure 5As shown, the absorption of the stray light-eliminating layer is most significant in the 400-600 nm range, and relatively significant in the 600-800 nm range. The average light absorption in the 400-800 nm range is 78.14 cm⁻¹. -1 .

Claims

1. A graded index glass characterized in that, The components are present in the following weight percentages: SiO2: 38-65%; Li2O: 1.5-5%; Na2O: 6-16%; SrO: 1-8%; B2O3: 2-12%; ZrO2: 2-10%; Ag2O: 1 x 10 -4 ~3%.

2. The graded index glass according to claim 1, wherein BaO: 0-10%; and / or K2O: 0-2%; and / or MgO: 0-5%; and / or ZnO: 0-10%; and / or Al2O3: 0-10%; and / or GeO2: 0-2%; and / or TiO2: 0-1%; and / or La2O3: 0-4%; and / or Y2O3: 0-6%; and / or Nb2O5: 0-2%; and / or Sb2O3: 0-0.6%; and / or SnO2: 0-1%.

3. Gradient index glass characterized in that, The components are expressed in weight percent, from SiO2: 38-65%; Li2O: 1.5-5%; Na2O: 6-16%; SrO: 1-8%; B2O3: 2-12%; ZrO2: 2-10%; Ag2O: 1 x 10 -4 ~3%; BaO: 0-10%; K2O: 0-2%; MgO: 0-5%; ZnO: 0-10%; Al2O3: 0-10%; GeO2: 0-2%; TiO2: 0-1%; La2O3: 0-4%; Y2O3: 0-6%; Nb2O5: 0-2%; Sb2O3: 0-0.6%; SnO2: 0-1%.

4. The graded-index glass according to any one of claims 1 to 3, characterized by The components thereof, expressed in weight percent, satisfy one or more of the following 5 cases: 1) Li2O / (Li2O+Na2O) is 0.15-0.30, preferably Li2O / (Li2O+Na2O) is 0.17-0.28, more preferably Li2O / (Li2O+Na2O) is 0.19-0.26; 2) (MgO+ZnO) / Na2O is 0.15-1.10, preferably (MgO+ZnO) / Na2O is 0.25-0.90, more preferably (MgO+ZnO) / Na2O is 0.35-0.75; 3) (SrO+BaO) / B2O3 is 0.75-2.70, preferably (SrO+BaO) / B2O3 is 0.90-2.00, more preferably (SrO+BaO) / B2O3 is 1.00-1.50; 4) Li2O / ZrO2 is 0.40-1.60, preferably Li2O / ZrO2 is 0.55-1.0, more preferably Li2O / ZrO2 is 0.60-0.85; 5) (ZnO+B2O3) / ZrO2 is 1.33-4.00, preferably (ZnO+B2O3) / ZrO2 is 1.66-3.50, more preferably (ZnO+B2O3) / ZrO2 is 2.00-3.

00.

5. The graded index glass according to any one of claims 1 to 3, characterized by of which the components are expressed in percentage by weight, in which: SiO2: 44-61 %, preferably SiO2: 50-57 %; and / or Li2O: 1.75-4.5 %, preferably Li2O: 2-4 %; and / or Na2O: 6.5-15 %, preferably Na2O: 7-14 %; and / or Ag2O: 1 x 10 -3 -1 %, preferably Ag2O: 0.01-0.5 %; and / or SrO: 1.5-7 %, preferably SrO: 2-6 %; and / or BaO: 1-9 %, preferably BaO: 2-8 %; and / or B2O3: 3-11 %, preferably B2O3: 4-10 %; and / or ZrO2: 3-9 %, preferably ZrO2: 4-8 %; and / or K2O: 0-1 %; and / or MgO: 0-4 %, preferably MgO: 0.5-3 %; and / or ZnO: 0-8 %, preferably ZnO: 2-6 %; and / or Al2O3: 0-5 %; and / or GeO2: 0-0.5 %; and / or TiO2: 0-0.5 %; and / or La2O3: 0-1 %; and / or Y2O3: 0-1.5 %; and / or Nb2O5: 0-1 %; and / or Sb2O3: 0-0.4 %, preferably Sb2O3: 0.1-0.3 %; and / or SnO2: 0-0.8 %, preferably SnO2: 0-0.6 %.

6. The graded-index glass according to any one of claims 1 to 3, characterized by The components thereof do not contain K2O; and / or do not contain Al2O3; and / or do not contain GeO2; and / or do not contain TiO2; and / or do not contain La2O3; and / or do not contain Y2O3; and / or do not contain Nb2O5; and / or do not contain CeO2; and / or do not contain CaO; and / or do not contain P2O5; and / or do not contain Gd2O3; and / or do not contain Ta2O5.

7. The graded index glass according to any one of claims 1 to 3, wherein The gradient index glass has a depth of the stray light eliminating layer of 0.1-50 μm, preferably 1-40 μm, more preferably 5-30 μm; and / or an average light absorption of the stray light eliminating layer of 400-800 nm of more than 10 cm -1 , preferably more than 30 cm -1 , more preferably more than 50 cm -1 .

8. Glass material, characterized in that, The components thereof, expressed in weight percent, contain: SiO2: 38-65%; Li2O: 2-7%; Na2O: 5-12%; SrO: 1-8%; B2O3: 2-12%; ZrO2: 2-10%.

9. The glass material of claim 8, wherein, comprising, in percent by weight: BaO: 0-10%; and / or K2O: 0-2%; and / or MgO: 0-5%; and / or ZnO: 0-10%; and / or Al2O3: 0-10%; and / or GeO2: 0-2%; and / or TiO2: 0-1%; and / or La2O3: 0-4%; and / or Y2O3: 0-6%; and / or Nb2O5: 0-2%; and / or Sb2O3: 0-0.6%; and / or SnO2: 0-1%.

10. Glass material, characterized in that, comprising, in percent by weight: SiO2: 38-65%; Li2O: 2-7%; Na2O: 5-12%; SrO: 1-8%; B2O3: 2-12%; ZrO2: 2-10%; BaO: 0-10%; K2O: 0-2%; MgO: 0-5%; ZnO: 0-10%; Al2O3: 0-10%; GeO2: 0-2%; TiO2: 0-1%; La2O3: 0-4%; Y2O3: 0-6%; Nb2O5: 0-2%; Sb2O3: 0-0.6%; SnO2: 0-1%. comprising, in percent by weight: SiO2: 38-65%; Li2O: 2-7%; Na2O: 5-12%; SrO: 1-8%; B2O3: 2-12%; ZrO2: 2-10%; BaO: 0-10%; K2O: 0-2%; MgO: 0-5%; ZnO: 0-10%; Al2O3: 0-10%; GeO2: 0-2%; TiO2: 0-1%; La2O3: 0-4%; Y2O3: 0-6%; Nb2O5: 0-2%; Sb2O3: 0-0.6%; SnO2: 0-1%.

11. The glass material according to any one of claims 8 to 10, characterized in that, comprising, in percent by weight: SiO2: 38-65%; Li2O: 2-7%; Na2O: 5-12%; SrO: 1-8%; B2O3: 2-12%; ZrO2: 2-10%; BaO: 0-10%; K2O: 0-2%; MgO: 0-5%; ZnO: 0-10%; Al2O3: 0-10%; GeO2: 0-2%; TiO2: 0-1%; La2O3: 0-4%; Y2O3: 0-6%; Nb2O5: 0-2%; Sb2O3: 0-0.6%; SnO2: 0-1%. comprising, in percent by weight: SiO2: 38-65%; Li2O: 2-7%; Na2O: 5-12%; SrO: 1-8%; B2O3: 2-12%; ZrO2: 2-10%; BaO: 0-10%; K2O: 0-2%; MgO: 0-5%; ZnO: 0-10%; Al2O3: 0-10%; GeO2: 0-2%; TiO2: 0-1%; La2O3: 0-4%; Y2O3: 0-6%; Nb2O5: 0-2%; Sb2O3: 0-0.6%; SnO2: 0-1%. comprising, in percent by weight: SiO2: 38-65%; Li2O: 2-7%; Na2O: 5-12%; SrO: 1-8%; B2O3: 2-12%; ZrO2: 2-10%; BaO: 0-10%; K2O: 0-2%; MgO: 0-5%; ZnO: 0-10%; Al2O3: 0-10%; GeO2: 0-2%; TiO2: 0-1%; La2O3: 0-4%; Y2O3: 0-6%; Nb2O5: 0-2%; Sb2O3: 0-0.6%; SnO2: 0-1%. comprising, in percent by weight: SiO2: 38-65%; Li2O: 2-7%; Na2O: 5-12%; SrO: 1-8%; B2O3: 2-12%; ZrO2: 2-10%; BaO: 0-10%; K2O: 0-2%; MgO: 0-5%; ZnO: 0-10%; Al2O3: 0-10%; GeO2: 0-2%; TiO2: 0-1%; La2O3: 0-4%; Y2O3: 0-6%; Nb2O5: 0-2%; Sb2O3: 0-0.6%; SnO2: 0-1%. ​ ​ 12. The glass material according to any one of claims 8 to 10, characterized in that, its components are expressed in weight percent, wherein: SiO2: 44-61%, preferably SiO2: 50-57%; and / or Li2O: 2.5-6.5%, preferably Li2O: 3-6%; and / or Na2O: 6-11.5%, preferably Na2O: 7-11%; and / or SrO: 1.5-7%, preferably SrO: 2-6%; and / or BaO: 1-9%, preferably BaO: 2-8%; and / or B2O3: 3-11%, preferably B2O3: 4-10%; and / or ZrO2: 3-9%, preferably ZrO2: 4-8%; and / or K2O: 0-1%; and / or MgO: 0-4%, preferably MgO: 0.5-3%; and / or ZnO: 0-8%, preferably ZnO: 2-6%; and / or Al2O3: 0-5%; and / or GeO2: 0-0.5%; and / or TiO2: 0-0.5%; and / or La2O3: 0-1%; and / or Y2O3: 0-1.5%; and / or Nb2O5: 0-1%; and / or Sb2O3: 0-0.4%, preferably Sb2O3: 0.1-0.3%; and / or SnO2: 0-0.8%, preferably SnO2: 0-0.6%.

13. The glass material according to any one of claims 8 to 10, characterized in that, its components do not contain K2O; and / or do not contain Al2O3; and / or do not contain GeO2; and / or do not contain TiO2; and / or do not contain La2O3; and / or do not contain Y2O3; and / or do not contain Nb2O5; and / or do not contain CeO2; and / or do not contain CaO; and / or do not contain P2O5; and / or do not contain Gd2O3; and / or do not contain Ta2O5.

14. The glass material according to any one of claims 8 to 10, characterized in that, The glass material has a refractive index of 1.550 to 1.600, preferably 1.555 to 1.595, more preferably 1.560 to 1.590; and / or an Abbe number of 55.00 to 60.00; and / or a transition temperature of 485°C or higher, preferably 490°C or higher, more preferably 495°C or higher; and / or a water resistance of class 3 or higher, preferably class 2 or higher; and / or an acid resistance of class 2 or higher, preferably class 1; and / or a coefficient of thermal expansion a 20-120℃ 60 x 10 -7 / °C to 100 x 10 -7 / °C, preferably 65 x 10 -7 / °C to 95 x 10 -7 / °C, more preferably 70 x 10 -7 / °C to 90 x 10 -7 / °C; and / or a Young's modulus of 85 x 10 9 Pa or higher, preferably 87 x 10 9 Pa or higher, more preferably 89 x 10 9 Pa or higher; and / or a Poisson's ratio of 0.230 to 0.250, preferably 0.232 to 0.248, more preferably 0.232 to 0.246; and / or a micro Vickers hardness of 55 x 10 9 Pa or higher, preferably 56 x 10 9 Pa or higher, more preferably 57 x 10 9 Pa or higher; and / or a density of 2.90 g / cm 3 or lower, preferably 2.87 g / cm 3 or lower, more preferably 2.84 g / cm 3 or lower; and / or a clearing temperature of 1400°C or lower, preferably 1300°C or lower, more preferably 1200°C or lower; and / or an anti-crystallization property of class 3 or higher, preferably class 2 or higher, more preferably class 1.

15. Glass preform, characterized in that, made of a glass material according to any one of claims 8-14.

16. Glass element, characterized in that made of a glass material according to any one of claims 8-14, or made of a glass preform according to claim 15.

17. A gradient index glass characterized by, made of a glass material according to any one of claims 8-14.

18. A gradient index lens characterized by, made of a gradient-index glass according to any one of claims 1-7, 17.

19. An apparatus, comprising: containing a gradient-index glass according to any one of claims 1-7, 17; and / or containing a glass material according to any one of claims 8-14; and / or containing a glass element according to claim 16; and / or containing a gradient-index lens according to claim 18.

20. A method of making a gradient index glass, characterized by, the method comprising the steps of: 1) forming a glass material; 2) drawing the glass material into a glass filament; 3) ion exchange (I); 4) ion exchange (II); 5) heat treatment.

21. The method of making a gradient-index glass according to claim 20, wherein The ion exchange (I) is carried out with a salt bath containing only Na as cation + The ion exchange is carried out with a salt bath containing Na and Ag as cations + and Ag + The ion exchange is carried out with a salt bath containing Na and Ag as cations + The ion exchange (II) is carried out with a salt bath containing Na and Ag as cations, Ag being present in a molar percentage of 0.1 to 20%, preferably of 0.5 to 15%, more preferably of 1 to 10% with respect to the total cations of the bath. The ion exchange (II) is carried out at a temperature of 280 to 380°C, preferably of 290 to 370°C, more preferably of 300 to 360°C, for a time of 0.5 to 60 minutes, preferably of 1 to 45 minutes, more preferably of 2 to 30 minutes. The heat treatment is carried out at a temperature of 380 to 490°C, preferably of 390 to 485°C, more preferably of 400 to 480°C, for a time of 0.1 to 30 hours, preferably of 0.2 to 20 hours, more preferably of 0.3 to 16 hours.

Images