High-refractive-index optical glass, preparation method therefor and optical element

Abstract

The present disclosure provides high-refractive-index optical glass, a preparation method therefor, and an optical element. The high-refractive-index optical glass comprises the following components on a cation basis: 10-30% of P5+, 0-13.5% of Li+, 5-28% of Na+, 0-5.9% of K+, 3-25% of Ba2+, 0-23% of Sr2+, 12-30% of Nb5+, 4-15% of Ti4+, 0-15% of B3+, and 0-2% of Si4+. These percentages are all mole percentages. The high-refractive-index optical glass of the present disclosure has excellent crystallization property, transmittance, and chemical stability, is easy to process, has a negative refractive index temperature coefficient, is suitable for secondary pressing and precision molding, and facilitates batch production.

Description

High refractive index optical glass, preparation method thereof and optical element Technical Field

[0001] The present invention relates to a high-refractive-index optical glass and a preparation method thereof and an optical element, belonging to the technical field of optical glass. Background Art

[0002] High refractive index optical glass is mainly used in optical imaging equipment such as car cameras, mobile phones, cameras, projectors, optical instruments, etc. In particular, in recent years, with the rapid development of car lenses, the requirements for optical systems have become more and more, especially higher requirements for vehicle safety and environmental adaptability. In order to improve the safety of vehicles under harsh environmental conditions such as high temperature and humidity, rapid temperature changes, acid rain erosion, etc., car manufacturers often adopt fixed focus system design, but the problem of temperature drift needs to be solved. This requires the matching of optical lenses with negative refractive index temperature coefficient and positive refractive index temperature coefficient, and the lenses need to have excellent chemical stability. In addition, the higher the refractive index, the fewer lenses are required, which is more conducive to improving the reliability of fixed focus car systems. At present, the refractive index temperature coefficient of glass with a refractive index higher than 1.81 is within 1×10 -6 / ℃ and above, which cannot meet the application requirements of vehicles.

[0003] Furthermore, in the field of optical imaging, in addition to utilizing a negative refractive index temperature coefficient to address temperature drift, optical designers are also seeking to reduce the size of optical systems, leading to a growing demand for high-refractive-index aspheric lenses. Currently, however, the softening temperature of glass with a refractive index greater than 1.81 is generally above 600°C. While this allows for molding, it significantly reduces mold life and increases molding costs. This creates a need for optical material manufacturers to develop high-refractive-index, low-melting-point glass with a negative refractive index temperature coefficient.

[0004] Patent application CN103058517A discloses optical glass containing 20-60% TeO2 and 20-40% GeO2. TeO2 is toxic and harmful to the environment and human health. When melting glass raw materials in a platinum crucible or a melting tank where the portion in contact with the molten glass is platinum, tellurium and platinum alloy together, resulting in poor heat resistance in the resulting alloyed area. This can cause perforations in these areas, leading to molten glass outflow accidents. GeO2 is relatively expensive, and adding too much can significantly increase the cost of the glass.

[0005] Patent application CN1955128A discloses an optical glass containing 13-21% GeO2. Patent application CN101734855A also discloses an optical glass containing 7.25-14% GeO2. GeO2 is relatively expensive, and adding too much would significantly increase the cost of the glass, which is not in line with the demand for low-cost glass.

[0006] The optical glass disclosed in patent application CN106517765A contains not only 11-20% TeO2 but also 10-21% Ga2O3. Ga2O3 is relatively expensive, and adding too much will significantly increase the cost of the glass.

[0007] The optical glass disclosed in patent application CN103113023A contains 1-10% Sb2O3. Excessive Sb2O3 content can worsen the coloration of the glass. Furthermore, when the glass preform is manufactured using press molding, the surface of the preform is prone to unevenness and blurring, which cannot meet the increasing demands for optical design in recent years.

[0008] Optical glasses disclosed in patent applications such as CN1955128A, JP2012-224496A, JP2012-232874A, CN102765881A, CN102958858A, CN103113023A, and JP2012-236756A also contain more than 50% Bi2O3. Excessive Bi2O3 addition not only increases corrosion to melting vessels but also increases the density of the glass, reducing its devitrification resistance. Summary of the Invention

[0009] Problems to be solved by the invention

[0010] One of the purposes of the present disclosure is to provide a high-refractive-index optical glass. The high-refractive-index optical glass disclosed herein has excellent crystallization performance, transmittance and chemical stability, is easy to process, and has a negative refractive index temperature coefficient. It is suitable for secondary pressing and precision molding, and is easy to achieve mass production.

[0011] The present disclosure also provides a method for preparing optical glass, which is simple and easy to prepare, and the raw materials are easy to obtain, and is suitable for mass production.

[0012] The present disclosure also provides an optical element or an optical preform.

[0013] Solutions for solving problems

[0014] [1] An optical glass comprising the following components calculated as cations:

[0015] P 5+ : 10-30%, preferably 12-28%, more preferably 15-25%;

[0016] Li + : 0-13.5%, preferably 3-10%, more preferably 5-8%;

[0017] Na +: 5-28%, preferably 8-25%, more preferably 10-20%;

[0018] K + : 0-5.9%, preferably 1-5%, more preferably 2-4%;

[0019] Ba 2+ : 3-25%, preferably 5-20%, more preferably 10-20%;

[0020] Sr 2+ : 0-23%, preferably 5-20%, more preferably 10-20%;

[0021] Nb 5+ : 12-30%, preferably 15-28%, more preferably 17-25%;

[0022] Ti 4+ : 4-15%, preferably 6-13%, more preferably 8-12%;

[0023] B 3+ : 0-15%, preferably 3-12%, more preferably 5-10%;

[0024] Si 4+ : 0-2%, preferably 0.3-1.5%;

[0025] The above percentages are all molar percentages.

[0026] [2] The optical glass according to [1], wherein, in terms of molar percentage of cations, Si 4+ With B 3+ The sum of the contents ∑Si 4+ +B 3+ It is 0.5-17%, preferably 3-15%, more preferably 5-10%.

[0027] [3] The optical glass according to [1] or [2], wherein, in terms of molar percentage of cations, Li + 、Na + With K + The sum of the contents ∑Li + +Na + +K + 11-38%, preferably 13-35%, more preferably 15-30%; and / or,

[0028] Li + Tong Li + 、Na + With K + The ratio of the sum of the contents of Li + / ∑(Li + +Na ++K + ) is 0.6 or less, preferably 0.4 or less.

[0029] [4] The optical glass according to any one of [1] to [3] above, wherein, in terms of molar percentage of cations, P 5+ 、B 3+ With Si 4+ The sum of the contents ∑P 5+ +B 3+ +Si 4+ 20-39%, preferably 23-37%, more preferably 25-35%; and / or,

[0030] B 3+ With Si 4+ The sum of the contents of P 5+ The ratio ∑(Si 4+ +B 3+ ) / P 5+ It is 1.1 or less, preferably 1.0 or less, and more preferably 0.8 or less.

[0031] [5] The optical glass according to any one of [1] to [4] above, wherein, in terms of molar percentage of cations, Nb 5+ With Ti 4+ The sum of the contents ∑Nb 5+ +Ti 4+ 21-38%, preferably 23-35%, more preferably 25-30%; and / or,

[0032] Ti 4+ Same as Nb 5+ With Ti 4+ The ratio of the sum of the contents of Ti 4+ / ∑(Nb 5+ +Ti 4+ ) is 0.5 or less, preferably 0.35 or less, more preferably 0.3 or less.

[0033] [6] The optical glass according to any one of [1] to [5] above, wherein, in terms of molar percentage of cations, Sr 2+ with Ba 2+ The sum of the contents ∑Sr 2+ +Ba 2+ 5-32%, preferably 8-30%, more preferably 10-25; and / or,

[0034] Sr 2+ with Ba 2+ The content ratio of Sr 2+ / Ba 2+ It is 4.3 or less, preferably 3.8 or less, and more preferably 3.0 or less.

[0035] [7] The optical glass according to any one of [1] to [6] above, wherein the refractive index of the optical glass is 1.812-1.898, preferably 1.82-1.88; the Abbe number is 18-28, preferably 19-26; and / or

[0036] The coloration of the optical glass λ 70 The λ in / λ5 70 Below 430 nm, preferably below 420 nm; λ5 below 380 nm, preferably below 375 nm.

[0037] [8] The optical glass according to any one of [1] to [7], wherein the refractive index temperature coefficient dn / dt of the optical glass at 20 to 40°C is -1.6×10 -6 / ℃ or less, preferably -2.0×10 -6 / ℃ or below; and / or,

[0038] The relaxation temperature of the optical glass is not more than 600°C, preferably not more than 590°C.

[0039] [9] A method for preparing the optical glass according to any one of [1] to [8] above, comprising weighing the components of the optical glass in a prescribed ratio, mixing them uniformly, and then melting, forming and annealing them to obtain the optical glass.

[0040]

[0010] An optical element comprising the optical glass according to any one of [1] to [8] above.

[0041] Effects of the Invention

[0042] The high-refractive-index optical glass disclosed herein has excellent crystallization performance, transmittance and chemical stability, is easy to process, and has a negative refractive index temperature coefficient. It is suitable for secondary pressing and precision molding, and is easy to achieve mass production.

[0043] Furthermore, the preparation method of the high refractive index optical glass disclosed in the present invention is simple and easy, the raw materials are easy to obtain, and it is suitable for mass production. DETAILED DESCRIPTION

[0044] Various exemplary embodiments, features, and aspects of the present disclosure are described in detail below. The word "exemplary" is used herein to mean "serving as an example, embodiment, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as superior or preferred over other embodiments.

[0045] In addition, numerous specific details are provided in the following detailed description to better illustrate the present disclosure. Those skilled in the art will appreciate that the present disclosure can be practiced without certain specific details. In other instances, methods, means, equipment, and steps well known to those skilled in the art are not described in detail in order to highlight the main points of the present disclosure.

[0046] Unless otherwise stated, the units used in this specification are international standard units, and the numerical values ​​and numerical ranges appearing in this disclosure should be understood to include the inevitable systematic errors in industrial production.

[0047] In this specification, the use of "may" includes both the meaning of performing a certain process and the meaning of not performing a certain process.

[0048] In this specification, references to "some specific / preferred embodiments," "other specific / preferred embodiments," "embodiments," etc., mean that the specific elements (e.g., features, structures, properties, and / or characteristics) described in connection with the embodiments are included in at least one embodiment described herein, and may or may not be present in other embodiments. In addition, it should be understood that the elements may be combined in various embodiments in any suitable manner.

[0049] In this specification, the numerical range expressed using "a numerical value A to a numerical value B" means a range including the endpoints A and B.

[0050] In this specification, when "normal temperature" or "room temperature" is used, the temperature may be 15-25°C.

[0051] This disclosure is based on P 5+ -Ti 4+ -Nb 5+ -R + (R is Li, Na or K) system as the basis, a glass suitable for secondary pressing and precision molding is obtained, which has a negative refractive index temperature coefficient, good crystallization performance, high transmittance, chemical stability and excellent process performance.

[0052] The present disclosure provides a high refractive index optical glass comprising the following components calculated as ions:

[0053] P 5+ : 10-30%, preferably 12-28%, more preferably 15-25%;

[0054] Li + : 0-13.5%, preferably 3-10%, more preferably 5-8%;

[0055] Na +: 5-28%, preferably 8-25%, more preferably 10-20%;

[0056] K + : 0-5.9%, preferably 1-5%, more preferably 2-4%;

[0057] Ba 2+ : 3-25%, preferably 5-20%, more preferably 10-20%;

[0058] Sr 2+ : 0-23%, preferably 5-20%, more preferably 10-20%;

[0059] Nb 5+ : 12-30%, preferably 15-28%, more preferably 17-25%;

[0060] Ti 4+ : 4-15%, preferably 6-13%, more preferably 8-12%;

[0061] B 3+ : 0-15%, preferably 3-12%, more preferably 5-10%;

[0062] Si 4+ : 0-2%, preferably 0.3-1.5%;

[0063] The above percentages are all molar percentages.

[0064] The raw materials are introduced in various forms that can introduce compounds with corresponding contents, such as carbonates, nitrates, carbonates, phosphates, etc.

[0065] P 5+ As a glass network generator, it can not only enhance the glass network structure, adjust the melting temperature and relaxation temperature of the glass, but also reduce the temperature coefficient of the refractive index of the glass. It is an essential component. 5+ If the content is too low, the glass structure will be loose, unable to incorporate more high refractive and high dispersion components, and not conducive to the decrease of sag temperature. The glass's resistance to devitrification, mechanical properties and chemical stability will deteriorate sharply. If P 5+ If the content is too high, the expected optical constants cannot be achieved and the chemical stability will also deteriorate. Therefore, in terms of the molar percentage of cations, P 5+ The content of is 10-30%, preferably 12-28%, more preferably 15-25%, further preferably 18-22%.

[0066] Li + It has the effect of reducing the partial dispersion ratio, significantly reducing the glass melting temperature, relaxation temperature and refractive index temperature coefficient, and improving thermal conductivity. +It has a small volume and can fill the glass network, strengthen the glass network structure and improve the crystallization performance. However, if its content is too high, it will have an aggregation effect, resulting in a sharp deterioration of devitrification resistance and accelerated crystallization speed. Therefore, in terms of the molar percentage of cations, Li + The content is below 13.5%, preferably 3-10%, more preferably 5-8%.

[0067] Na + With Li + It has a similar effect and is also an important component in the formation of glass, which can reduce the melting temperature, relaxation temperature and refractive index temperature coefficient of glass. + When the content of is too high, it is easy to cause the devitrification resistance and chemical stability to deteriorate, but if the content is too low, the free oxygen is insufficient, which will cause the glass structure to relax and the sag temperature to increase. Therefore, in terms of the molar percentage of cations, the present invention discloses Na + The content is 5-28%, preferably 8-25%, more preferably 10-20%, and further preferably 12-17%.

[0068] K + Performance and Na + Similar, but if K + Too high a content will lead to poor devitrification resistance and be detrimental to the adjustment of the temperature coefficient of refractive index and the improvement of transmittance. + The content is 5.9% or less, preferably 1-5%, more preferably 2-4%.

[0069] Li + 、Na + , K + In addition to lowering the melting and sag temperatures of the glass, it can also provide free oxygen, allowing B and Ti elements to strengthen the glass network structure in the form of tetrahedrons, thereby reducing glass coloration and improving transmittance. When the glass disclosed herein contains one or more of the above components, the crystallization performance and chemical stability of the glass can be improved through the mixed alkali effect. However, when Li + 、Na + With K + The sum of the contents ∑Li + +Na + +K + When it is too high, it is not conducive to the adjustment of optical constants, and it will also lead to excessive current in the melting process, increase production difficulty, and cause the crystallization performance, mechanical properties and chemical stability of the glass to decrease; when Li + 、Na + With K + The sum of the contents ∑Li + +Na + +K +When the content is too low, the glass will be difficult to melt, the crystallization temperature and the relaxation temperature will rise sharply, and the expected optical glass cannot be obtained. + +Na + +K + It is controlled to be 11-38%, preferably 13-35%, more preferably 15-30%, and further preferably 18-25%.

[0070] In this disclosure, Li + Tong Li + 、Na + With K + The ratio of the sum of the contents of Li + / ∑(Li + +Na + +K + ) also has a great influence on the performance of glass. + / ∑(Li + +Na + +K + ) is too small, the glass Ts is high, and the network gap is large, the glass structure is not stable enough, and the chemical stability becomes poor; when Li + / ∑(Li + +Na + +K + ) is too large, the glass tends to crystallize seriously, the interior is very easy to crystallize, and production is difficult. + / ∑(Li + +Na + +K + ) is controlled to be below 0.6, preferably below 0.4.

[0071] Si 4+ It is an optional component that acts as a glass network generator, which can improve the glass's resistance to devitrification and viscosity during molding. It can also improve the chemical stability of the glass, especially by introducing a small amount of Si into the phosphate system. 4+ , can significantly improve the crystallization performance of glass. 4+ The content of Si is too high, some 4+ It cannot even be melted into the glass, and it is easy to produce foreign matter during melting, which reduces the quality and chemical stability of the glass, and the melting temperature, relaxation temperature and crystallization temperature will increase significantly. 4+ The content is between 0-2%, preferably 0.3-1.5%.

[0072] B 3+ It is an optional component that acts as a glass network generator and can effectively improve the meltability of the glass, reduce the sag temperature, and improve the crystallization performance of the glass. 3+When the content is higher than 15%, the chemical stability of the glass becomes poor, and surface crystallization is easy to occur. The viscosity becomes smaller, and it becomes more difficult to eliminate the streaks, making it difficult to obtain the expected optical glass. 3+ The content is controlled to be 0-15%, preferably 3-12%, more preferably 5-10%.

[0073] The optical glass disclosed herein, when Si 4+ With B 3+ The sum of the contents ∑Si 4+ +B 3+ When it is too high, the chemical stability and crystallization performance of the optical glass will decrease, and it will be difficult to obtain the expected optical glass. 4+ With B 3+ The sum of the contents ∑Si 4+ +B 3+ When the content is too low, the tendency of glass crystallization increases and the crystallization speed is accelerated. Crystallization is very easy to occur inside and on the surface during molding. It is also easy to generate crystal nuclei or grain growth during the molding process. Therefore, in terms of the molar percentage of cations, the ∑Si in the optical glass of the present disclosure is 4+ +B 3+ It is 0.5-17%, preferably 3-15%, more preferably 5-10%.

[0074] P 5+ 、B 3+ 、Si 4+ As a glass network former, P is expressed in terms of the molar percentage of cations. 5+ 、B 3+ With Si 4+ The sum of the contents ∑P 5+ +B 3+ +Si 4+ It cannot be too high, otherwise the expected optical constants cannot be achieved, the crystallization performance, mechanical properties and chemical stability will also decrease, and the wear resistance will increase; but at the same time ∑P 5+ +B 3+ +Si 4+ It cannot be too low, otherwise the glass structure will be loose, the devitrification resistance will be poor, and the process will be more difficult. 5+ +B 3+ +Si 4+ It is 20-39%, preferably 23-37%, more preferably 25-35%, and further preferably 28-33%.

[0075] In this disclosure, B 3+ With Si 4+ The sum of the contents of P 5+ The ratio ∑(Si 4+ +B 3+ ) / P 5+The influence on glass performance is also relatively large. If ∑(Si 4+ +B 3+ ) / P 5+ If the value is too large, the crystallization performance of the glass will be significantly reduced, which is mainly manifested in the increase of crystallization temperature or the increase of crystallization, and the process performance such as melting will also deteriorate, which is not conducive to obtaining glass with excellent performance. 4+ +B 3+ / P 5+ It is 1.1 or less, preferably 1.0 or less, more preferably 0.8 or less, and further preferably 0.6 or less.

[0076] Ba 2+ It is an essential component of the glass disclosed herein, which can effectively reduce the temperature coefficient of refractive index of the glass and improve the melting and crystallization properties of the glass. 2+ It can improve the chemical stability and devitrification resistance of glass, and is beneficial to improve the internal transmittance and mechanical properties of glass. 2+ When the content of Ba is too low, it is not conducive to improving the coloring, transmittance and chemical stability of the glass, especially acid resistance, moisture resistance and water resistance; when Ba 2+ When the content of Ba is too high, the chemical stability of the glass, such as water resistance, washing resistance, etc., as well as the crystallization performance will be significantly deteriorated, and the density will increase significantly. 2+ The content of is 3-25%, preferably 5-20%, more preferably 10-20%, further preferably 13-18%.

[0077] Sr 2+ The role of Ba 2+ Similar to the two, when they exist at the same time, the properties of the glass such as crystallization performance and chemical stability can be improved through the mixed alkaline earth metal effect. 2+ If the content is too high, the crystallization performance and chemical stability will be deteriorated, and it will not be conducive to the reduction of the temperature coefficient of refractive index. 2+ The content is 0-23%, preferably 5-20%, more preferably 10-20%, and further preferably 13-18%.

[0078] Ba 2+ and Sr 2+ The introduction of Sr can not only increase the free oxygen in the glass, reduce the coloring of the glass, improve the transmittance, enhance the network structure and improve the crystallization performance, but also effectively reduce the temperature coefficient of the refractive index of the glass. 2+ with Ba 2+ The sum of the contents ∑Sr 2+ +Ba 2+When excessive amounts of Sr are introduced, the chemical stability of the glass will decrease significantly, the density will increase, and the expected optical constants will not be achieved. 2+ with Ba 2+ The sum of the contents ∑Sr 2+ +Ba 2+ When it is too low, it is difficult to obtain the expected temperature coefficient of refractive index, which is not conducive to the adjustment of optical constants. In addition, due to insufficient free oxygen, the glass structure will become loose, and the crystallization performance and chemical stability will deteriorate. Therefore, in terms of the molar percentage of cations, Sr 2+ with Ba 2+ The sum of the contents ∑Sr 2+ +Ba 2+ It is 5-32%, preferably 8-30%, more preferably 10-25%, further preferably 13-22%, and further preferably 15-20%.

[0079] In addition, when Sr 2+ with Ba 2+ The content ratio of Sr 2+ / Ba 2+ When it is too large, the crystallization performance of the glass will deteriorate. Therefore, in terms of the molar percentage of cations, Sr 2+ / Ba 2+ It is 4.3 or less, preferably 3.8 or less, more preferably 3.0 or less, and further preferably 2.0 or less.

[0080] Nb 5+ It is an essential component to improve the refractive index and dispersion of glass. When added in appropriate amounts, it can improve the resistance to devitrification and chemical stability. 5+ If the content of Nb is too high, the temperature coefficient of refractive index will increase, the resistance to devitrification of the glass will drop sharply, the crystallization temperature will increase, the crystallization speed will accelerate, and foreign matter will be easily generated during the production process, affecting the internal quality of the glass. 5+ The content of the ingredient is 12-30%, preferably 15-28%, more preferably 17-25%, and further preferably 18-22%.

[0081] Ti 4+ The component is an essential component that can increase the refractive index and dispersion of glass and improve the chemical stability and resistance to devitrification of glass. 4+ If the content is too high, the transmittance in the short wavelength region of visible light will be greatly reduced and the temperature coefficient of refractive index will increase; if the Ti 4+ If the content is too low, the crystallization performance of the glass will deteriorate, the crystallization speed will increase, and the production difficulty will increase greatly. Therefore, in terms of the molar percentage of cations, Ti 4+ The content is 4-15%, preferably 6-13%, more preferably 8-12%.

[0082] Nb5+ and Ti 4+ As the main component of the present invention, it plays a vital role in the optical properties of glass. 5+ With Ti 4+ The sum of the contents ∑Nb 5+ +Ti 4+ When it is too low, it is difficult to achieve the required high refraction and high dispersion. 5+ With Ti 4+ The sum of the contents ∑Nb 5+ +Ti 4+ When it is too high, the glass's resistance to devitrification, transmittance, crystallization performance, etc. will deteriorate, and the expected refractive index temperature coefficient will not be achieved; if Nb 5+ The content is too low to achieve the expected optical constants. Therefore, in terms of the molar percentage of cations, ∑Nb 5+ +Ti 4+ It is 21-38%, preferably 23-35%, more preferably 25-30%.

[0083] At the same time, Ti 4+ Same as Nb 5+ With Ti 4+ The ratio of the sum of the contents of Ti 4+ / ∑Nb 5+ +Ti 4+ It also has a great influence on the crystallization and transmittance of glass. 4+ / ∑Nb 5+ +Ti 4+ If the value is too large, the transmittance of the glass will drop sharply and the crystallization performance will deteriorate sharply. Therefore, in order to obtain an optical glass with excellent crystallization performance and light transmission performance, the molar percentage of the cation is 4+ / ∑Nb 5+ +Ti 4+ It is 0.5 or less, preferably 0.35 or less, and further preferably 0.3 or less.

[0084] Sb 3+ The presence of Sb will increase the coloring of the glass, and when the glass preform is manufactured by press molding, the surface of the molded body is prone to unevenness and blur, which cannot meet the requirements for optical design that have increased in recent years. Therefore, Sb is not added in the formula of this disclosure. 3+ .

[0085] Ta 5+ 、Ge 4+ Not only does it make the glass denser, but its raw material price is also extremely expensive, which does not meet the modern demand for lightweight and low cost. Preferably, Ta is not added in the formula of the present disclosure. 5+ 、Ge 4+ wait.

[0086] Yb 3+ There is absorption in the near infrared band, which is not conducive to improving the transmittance of the glass. Preferably, Yb is not added to the formula disclosed in this disclosure. 3+ .

[0087] Ga 3+ The price of is relatively expensive, and adding too much will greatly increase the cost of glass. 3+ The addition of Ga will not only increase the corrosion of the melting vessel, but also increase the density of the glass and devitrification resistance. 3+ and Bi 3+ .

[0088] Zn 2+ and Ca 2+ It will lead to an increase in the temperature coefficient of refractive index and a significant deterioration in the crystallization performance. Therefore, it is preferred that the present invention does not contain Zn 2+ and Ca 2+ .

[0089] Th element, Pb element, As element, Cd element, Hg element, Sn element, Fe element, Co element, Ce element, Te element, S element, V element, Mo element, Cr element, Mn element, Ni element, Cu element, Ag element, etc. are harmful to the environment or easily color the glass. Preferably, the above-mentioned harmful elements are not added to the formula disclosed in the present invention.

[0090] The anion of the optical glass of the present disclosure may be element O. Since element F is a component that is easily volatile or hygroscopic, it will produce volatile streaks, making production more difficult. Preferably, element F is not added to the composition of the optical glass of the present disclosure.

[0091] In order to ensure the transmittance of the optical glass described in the present disclosure, preferably, the high refractive index optical glass provided by the present disclosure does not contain Tl elements, Os elements, Be elements, Se elements, etc.

[0092] The refractive index of the optical glass disclosed herein is 1.812-1.898, preferably 1.82-1.88; the Abbe number is 18-28, preferably 19-26. The refractive index temperature coefficient dn / dt of the optical glass at 20-40°C is -1.6×10 -6 / ℃ or less, preferably -2.0×10 -6 / ℃ below.

[0093] The coloration of the optical glass λ 70 The λ in / λ5 70 Below 430 nm, preferably below 420 nm; λ5 below 380 nm, preferably below 375 nm.

[0094] The transition temperature Tg of the optical glass is not more than 580°C, preferably not more than 570°C, and the relaxation temperature of the optical glass is not more than 600°C, preferably not more than 590°C.

[0095] The abrasiveness F of the optical glass disclosed herein A The hardness can be 98-166, and the hardness can be 480×10 7 Pa-585×10 7 Pa, density can be 3.59-3.72g / cm 3 .

[0096] In addition, the water resistance, acid resistance, alkali resistance, and washing resistance of the optical glass disclosed herein can all reach level 1.

[0097] The present disclosure also provides a method for preparing the high-refractive-index optical glass according to the present disclosure, comprising weighing the raw materials of each component of the high-refractive-index optical glass according to a proportion, mixing them uniformly, melting them, forming them, and annealing them to obtain the high-refractive-index optical glass.

[0098] Specifically, the preparation method includes: weighing each component raw material according to a specified ratio, mixing them uniformly to form a batch material, and placing the prepared batch material into a melting device made of quartz or corundum, etc., introducing an oxidizing gas at a temperature of 1100-1350°C, melting and stirring them uniformly, draining and drying the poured broken glass, and then placing them into a crucible made of precious metals (Au, Pt, etc.) for secondary melting. The batch material can also be directly placed in a precious metal crucible for melting, stirring and clarifying. After melting, stirring and clarifying for 16-24 hours, the temperature is lowered to 1000-1250°C, and poured or leaked into a forming mold for molding, or directly pressed into shape, and finally annealed and cooled before processing to obtain the optical glass or optical element disclosed herein.

[0099] The present invention also provides an optical element, which includes primary and secondary molded parts, preforms and precision molded optical elements made of the high refractive index optical glass disclosed in the present invention.

[0100] Example

[0101] The embodiments of the present disclosure will be described in detail below with reference to the examples. However, those skilled in the art will appreciate that the following examples are intended only to illustrate the present disclosure and should not be construed as limiting the scope of the present disclosure. Where specific conditions are not specified in the examples, the experiments were performed under conventional conditions or the conditions recommended by the manufacturer. Where the manufacturer of the reagents or instruments is not specified, all are commercially available conventional products.

[0102] The compound raw materials corresponding to the components in Example 1-66 in Table 1-11: Ba(PO3)2, NaPO3, Li2CO3, Na2CO3, KNO3, BaCO3, SrCO3, Nb2O5, TiO2, H3BO3, SiO2 are weighed in proportion and mixed evenly to form a batch material, and the prepared batch material is put into a quartz crucible, melted and stirred at a temperature of 1100-1350°C in an oxidizing atmosphere for 6-8 hours, poured into clean water, drained, dried, and then put into a Pt crucible. After melting, stirring, and clarifying for 16-24 hours, the temperature is lowered to 1000-1250°C, kept warm for 1 hour, taken out of the furnace, and poured into a mold for molding. After the glass is annealed and cooled, the optical glass disclosed in the present invention can be obtained.

[0103] Comparative Example

[0104] The compound raw materials corresponding to the components of Comparative Examples AC in Table 12: Ba(PO3)2, NaPO3, Li2CO3, Na2CO3, KNO3, BaCO3, SrCO3, Nb2O5, TiO2, H3BO3, SiO2, CaCO3, and ZnO are weighed according to the specified proportions, and prepared using the same preparation method as in Examples 1-66 to obtain the optical glass of Comparative Examples AC.

[0105] Performance Testing

[0106] 1. Refractive index n d , Abbe number υ d

[0107] The refractive index n of the obtained optical glass was measured according to the test method of GB / T7962.1-2010. d , Abbe number υ d Determination of n d 、υ d The data are after annealing at -25℃.

[0108] 2. Glass abrasiveness F A

[0109] The abrasion resistance is measured according to the test method specified in GB / T 7962.19.

[0110] 3. Glass Knoop hardness HK

[0111] Knoop hardness is measured according to the test method specified in ISO 9385.

[0112] 4. Glass transition temperature Tg and relaxation temperature Ts

[0113] Measure according to the method specified in GB / T 7962.16.

[0114] 5. Density ρ

[0115] The density of the obtained optical glass was measured according to the test method of GB / T7962.20-2010.

[0116] 6. Coloring λ 70 / λ5

[0117] Coloration λ for optical glass short-wave transmission spectrum characteristics 70 / λ5 indicates. 70 The wavelength at which the glass transmittance reaches 70%, and λ5 is the wavelength at which the glass transmittance reaches 5%. The light transmittance of parallel-ground glass with a thickness of 10 ± 0.1 mm is measured according to the Japan Glass Industry Association's "Measurement Method for Coloration of Optical Glass," JOGIS02.

[0118] 7. Water resistance D W , acid resistance D A

[0119] According to the test method of JB / T10576-2006, the water resistance of the obtained optical glass is tested for chemical stability. W , acid resistance D A Conduct a test.

[0120] 8. Alkali resistance R OH

[0121] A 35mm×35mm×8mm sample with six polished sides was immersed in a well-stirred Na5P3O solution with a constant temperature of 50℃±3℃ and a concentration of 0.01mol / L. 10 1 hour in aqueous solution. According to the average value of leaching mass per unit area, the unit is mg / (cm 2 h), the optical glass washing resistance stability RP (S) is divided into five levels, see Table A below:

[0122] Table A

[0123] 9. Washing resistance RP

[0124] A sample with six polished sides and a size of 40 mm × 40 mm × 5 mm was immersed in a well-stirred sodium hydroxide aqueous solution at a constant temperature of 50°C ± 3°C and a concentration of 0.01 mol / l for 15 hours. The average leaching mass per unit area was expressed in mg / (cm 2 ·15h), the alkali resistance stability of optical glass R OH (S) is divided into five levels, see Table B below: Table B

[0125] 10. Temperature coefficient of refractive index

[0126] The temperature coefficient of the relative refractive index (dn / dt) of the glass of the embodiment was measured according to the minimum deviation angle method described in the national standard GB7962.04-2010 "Test methods for colorless optical glass Part 4: Temperature coefficient of refractive index" for light with a wavelength of 589.29 nm (d-line) when the temperature was changed from 20°C to 40°C.

[0127] 11. Number of internal bubbles

[0128] The bubbles inside the glass were tested according to the test method specified in GB / T7962.8-1987, and the results showed that 100cm 3 The number of bubbles in the glass, stones, crystals and other inclusions are also counted as bubbles.

[0129] 12. Crystallization performance test

[0130] The crystallization performance test was carried out as follows: samples obtained from various optical glasses were prepared, and these samples were kept at a temperature 20°C higher than the transition temperature (Tg) of each optical glass for 5 hours, and then kept at 900°C for 5 minutes. The interior of the glass cut into 3×3×1 mm glass pieces including the center of the sample after cooling was observed under a 50x optical microscope, the number of precipitated grains was measured, the number of grains per unit volume (mm) was calculated, and this value was defined as the grain number density.

[0131] 13. Stripe

[0132] The degree of streaking is checked using a parallel light path streak meter composed of a point light source and a lens. By rotating the glass, the streak image inside the direction of the glass cut surface where streaks are most likely to occur is checked and compared with the standard sample. The results are divided into the following levels, see Table C below:

[0133] Table C

[0134] The refractive index n of the optical glass prepared in Example 1-66 is d 、Abbe number υ d , wear degree F A , hardness HK, transition temperature Tg, relaxation temperature Ts, density ρ, coloration λ 70 / λ5、Water resistance D W , acid resistance D A , alkali resistance R OH , washing resistance RP and relative refractive index temperature coefficient of d line at 20-40°C, the number of internal bubbles, the number of crystallized particles, the stripe level, etc. are listed in Table 1-11; the data obtained by measuring comparative example AC are listed in Table 12.

[0135] Table 1: Glass composition and performance parameters of Examples 1-6

[0136] Table 2: Glass composition and performance parameters of Examples 7-12

[0137] Table 3: Glass composition and performance parameters of Examples 13-18

[0138] Table 4: Glass composition and performance parameters of Examples 19-24

[0139] Table 5: Glass composition and performance parameters of Examples 25-30

[0140] Table 6: Glass composition and performance parameters of Examples 31-36

[0141] Table 7: Glass composition and performance parameters of Examples 37-42

[0142] Table 8: Glass composition and performance parameters of Examples 43-48

[0143] Table 9: Glass composition and performance parameters of Examples 49-54

[0144] Table 10: Glass composition and performance parameters of Examples 55-60

[0145] Table 11: Glass composition and performance parameters of Examples 61-66

[0146] Table 12: Glass composition and performance parameters of Comparative Examples AC

[0147] It can be seen from Table 1-11 that the refractive index n of the optical glass of Examples 1-66 of the present disclosure is d is 1.812-1.898, Abbe number υ d The wear degree is 18-28, and its wear degree F A 98-166, hardness (×10 7 Pa) is 480-585, the transition temperature Tg is below 570℃, the relaxation temperature Ts is below 600℃, and the density is 3.59-3.72g / cm 3 , coloring degree λ 70 / λ5,λ 70The optical glass has a wavelength of λ not exceeding 430 nm, and a λ5 of λ not exceeding 380 nm. The glass's water resistance, acid resistance, alkali resistance, and washing resistance all reach Class 1. The optical glass disclosed herein has excellent manufacturing process performance and is suitable for mass production. In particular, the glass exhibits good crystallization performance and a low softening temperature, making it suitable for secondary pressing and molding.

[0148] As can be seen from Table 12, Comparative Example A contains more than 19% Ti 4+ , not only the crystallization performance deteriorates, but also the coloring degree deteriorates significantly; Comparative Example B contains more K + , does not contain Na + , the softening temperature exceeds 620℃, which greatly increases the molding cost. 2+ and Ca 2+ , which leads to an increase in the temperature coefficient of refractive index and a significant deterioration in crystallization performance.

[0149] It should be noted that, although the technical solutions of the present disclosure are described with specific examples, those skilled in the art will appreciate that the present disclosure should not be limited thereto.

[0150] While various embodiments of the present disclosure have been described above, the foregoing description is intended to be illustrative, non-exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is selected to best explain the principles of the embodiments, their practical applications, or technological improvements in the marketplace, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. An optical glass, characterized in that: It contains the following components calculated as cations: P 5+ : 10-30%, preferably 12-28%, more preferably 15-25%; Li + : 0-13.5%, preferably 3-10%, more preferably 5-8%; Na + : 5-28%, preferably 8-25%, more preferably 10-20%; K + : 0-5.9%, preferably 1-5%, more preferably 2-4%; Ba 2+ : 3-25%, preferably 5-20%, more preferably 10-20%; Sr 2+ : 0-23%, preferably 5-20%, more preferably 10-20%; Nb 5+ : 12-30%, preferably 15-28%, more preferably 17-25%; Ti 4+ : 4-15%, preferably 6-13%, more preferably 8-12%; B 3+ : 0-15%, preferably 3-12%, more preferably 5-10%; Si 4+ : 0-2%, preferably 0.3-1.5%; The above percentages are all molar percentages.

2. The optical glass according to claim 1, wherein In terms of molar percentage of cations, Si 4+ With B 3+ The sum of the contents ∑Si 4+ +B 3+ It is 0.5-17%, preferably 3-15%, more preferably 5-10%.

3. The optical glass according to claim 1 or 2, characterized in that: In terms of molar percentage of cations, Li + 、Na + With K + The sum of the contents ∑Li + +Na + +K + 11-38%, preferably 13-35%, more preferably 15-30%; and / or, Li + Tong Li + 、Na + With K + The ratio of the sum of the contents of Li + / ∑(Li + +Na + +K + ) is 0.6 or less, preferably 0.4 or less.

4. The optical glass according to any one of claims 1 to 3, characterized in that: In terms of molar percentage of cations, P 5+ 、B 3+ With Si 4+ The sum of the contents ∑P 5+ +B 3+ +Si 4+ 20-39%, preferably 23-37%, more preferably 25-35%; and / or, B 3+ With Si 4+ The sum of the contents of P 5+ The ratio ∑(Si 4+ +B 3+ ) / P 5+ It is 1.1 or less, preferably 1.0 or less, and more preferably 0.8 or less.

5. The optical glass according to any one of claims 1 to 4, characterized in that: In terms of molar percentage of cations, Nb 5+ With Ti 4+ The sum of the contents ∑Nb 5+ +Ti 4+ 21-38%, preferably 23-35%, more preferably 25-30%; and / or, Ti 4+ Same as Nb 5+ With Ti 4+ The ratio of the sum of the contents of Ti 4+ / ∑(Nb 5+ +Ti 4+ ) is 0.5 or less, preferably 0.35 or less, more preferably 0.3 or less.

6. The optical glass according to any one of claims 1 to 5, characterized in that: In terms of molar percentage of cations, Sr 2+ with Ba 2+ The sum of the contents ∑Sr 2+ +Ba 2+ 5-32%, preferably 8-30%, more preferably 10-25; and / or, Sr 2+ with Ba 2+ The content ratio of Sr 2+ / Ba 2+ It is 4.3 or less, preferably 3.8 or less, and more preferably 3.0 or less.

7. The optical glass according to any one of claims 1 to 6, characterized in that: The refractive index of the optical glass is 1.812-1.898, preferably 1.82-1.88; the Abbe number of the optical glass is 18-28, preferably 19-26; and / or, The coloration of the optical glass λ 70 The λ in / λ5 70 Below 430 nm, preferably below 420 nm; λ5 below 380 nm, preferably below 375 nm.

8. The optical glass according to any one of claims 1 to 7, characterized in that: The refractive index temperature coefficient dn / dt of the optical glass at 20-40°C is -1.6×10 -6 / ℃ or less, preferably -2.0×10 -6 / ℃ or below; and / or, The relaxation temperature of the optical glass is not more than 600°C, preferably not more than 590°C.

9. A method for preparing optical glass according to any one of claims 1 to 8, characterized in that: The process comprises weighing the components of the optical glass according to a prescribed ratio, uniformly mixing the components, melting, forming and annealing the components to obtain the optical glass.

10. An optical element, characterized in that: The optical glass comprises the optical glass according to any one of claims 1 to 8.

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