CN110316960B - Optical glass, glass preform, optical element and optical instrument - Google Patents

Abstract

The invention provides an optical glass, which comprises the following components in percentage by weight: SiO 2₂：41～58％；TiO₂：18～32％；Na₂O：3～18％；K₂O: 2-15%; BaO: 2-15%; SrO: 0 to 10 percent; CaO: 0 to 10 percent; MgO: 0 to 10%, wherein BaO/RO is 0.5 to 1.0, and RO is the total content of BaO, SrO, CaO and MgO. Through reasonable component design and proportion, the optical glass has proper hardness and excellent chemical stability while meeting the expected refractive index and Abbe number, and meets the application requirements in the fields of vehicle-mounted monitoring and security protection and the like.

Description

Optical glass, glass preform, optical element and optical instrument

Technical Field

The invention relates to optical glass, in particular to optical glass with a refractive index of 1.62-1.71 and an Abbe number of 28-36.

Background

In recent years, with the rapid popularization and use of digital cameras, video cameras, and camera phones, optical materials have also been rapidly developed toward high precision and miniaturization. The continuous fusion of optics and electronic information science and new material science, the application of optical glass as a photoelectron base material in the technical fields of optical transmission, optical storage, photoelectric display and the like is rapidly advanced. In recent years, optical elements and optical instruments have been rapidly developed in terms of digitization, integration, and high definition, and higher demands have been made on the performance of optical glasses used for optical elements of optical instruments and devices.

The optical glass with the refractive index of 1.62-1.71 and the Abbe number of 28-36 has important significance for simplifying an optical system and improving the imaging quality in the fields of optical design and optical communication. The optical glass meeting the optical performance can be applied to the fields of vehicle-mounted monitoring, security and protection and the like, and the optical glass is required to have higher hardness so as to resist the abrasion of sand and stones in the driving process of a vehicle and prolong the service life of the optical glass. The optical glass can be corroded by various liquids (such as acid, alkali, water and the like) in the environment during the use process, so the resistance of the optical glass to the corrosion, namely the chemical stability of the optical glass is important for the use precision and the service life of instruments.

Disclosure of Invention

The invention aims to provide optical glass with excellent chemical stability and higher hardness.

The technical scheme adopted by the invention for solving the technical problem is as follows: the optical glass comprises the following components in percentage by weight: SiO 2₂：41～58％；TiO₂：18～32％；Na₂O：3～18％；K₂O: 2-15%; BaO: 2-15%; SrO: 0 to 10 percent; CaO: 0 to 10 percent; MgO: 0 to 10%, wherein BaO/RO is 0.5 to 1.0, and RO is the total content of BaO, SrO, CaO and MgO.

Further, the optical glass comprises the following components in percentage by weight: b is₂O₃：0～10％；Ln₂O₃：0～5％；Nb₂O₅：0～8％；ZrO₂：0～5％；Li₂O：0～5％；Al₂O₃: 0 to 5 percent; ZnO: 0 to 5 percent; a clarifying agent: 0 to 1%, wherein Ln₂O₃Is La₂O₃、Gd₂O₃、Y₂O₃、Yb₂O₃One or more of Sb as clarifying agent₂O₃、SnO₂、SnO、CeO₂One or more of (a).

The optical glass comprises the following components in percentage by weight: SiO 2₂：41～58％；TiO₂：18～32％；Na₂O：3～18％；K₂O：2～15％；BaO：2～15％；SrO：0～10％；CaO：0～10％；MgO：0～10％；B₂O₃：0～10％；Ln₂O₃：0～5％；Nb₂O₅：0～8％；ZrO₂：0～5％；Li₂O：0～5％；Al₂O₃: 0 to 5 percent; ZnO: 0 to 5 percent; a clarifying agent: 0 to 1%, wherein BaO/RO is 0.5 to 1.0, RO is the total content of BaO, SrO, CaO and MgO, Ln₂O₃Is La₂O₃、Gd₂O₃、Y₂O₃、Yb₂O₃One or more of Sb as clarifying agent₂O₃、SnO₂、SnO、CeO₂One or more of (a).

Further, the above optical glass, its groupExpressed in weight percent, wherein: SiO 2₂: 42-55%; and/or TiO₂: 20-30%; and/or Na₂O: 5-16%; and/or K₂O: 3-12%; and/or BaO: 3-12%; and/or SrO: 0 to 5 percent; and/or CaO: 0 to 5 percent; and/or MgO: 0 to 5 percent; and/or B₂O₃: 0 to 5 percent; and/or Ln₂O₃: 0 to 3 percent; and/or Nb₂O₅: 0-6%; and/or ZrO₂: 0 to 3 percent; and/or Li₂O: 0 to 3 percent; and/or Al₂O₃: 0 to 3 percent; and/or ZnO: 0 to 3 percent; and/or a clarifying agent: 0 to 0.5%, wherein Ln₂O₃Is La₂O₃、Gd₂O₃、Y₂O₃、Yb₂O₃One or more of Sb as clarifying agent₂O₃、SnO₂、SnO、CeO₂One or more of (a).

Further, the optical glass comprises the following components in percentage by weight: BaO/RO is 0.7-1.0; and/or TiO₂/SiO₂0.35 to 0.75; and/or B₂O₃/SiO₂Is less than 0.15; and/or Na₂O/(Na₂O+K₂O) is 0.3 to 0.85; and/or Nb₂O₅/TiO₂Is 0.3 or less, wherein RO is the total content of BaO, SrO, CaO and MgO.

Further, the optical glass comprises the following components in percentage by weight: SiO 2₂: 43-50%; and/or TiO₂: 22-28%; and/or Na₂O: 8-14%; and/or K₂O: 4-10%; and/or BaO: 5-11%; and/or SrO: 0 to 3 percent; and/or CaO: 0 to 3 percent; and/or MgO: 0 to 3 percent; and/or B₂O₃: 0 to 3 percent; and/or Ln₂O₃: 0 to 1 percent; and/or Nb₂O₅: 0 to 3 percent; and/or ZrO₂: 0-2%; and/or Li₂O: 0-2%; and/or Al₂O₃: 0 to 1 percent; and/or ZnO: 0 to 1 percent; and/or Sb₂O₃: 0 to 0.5%, wherein Ln₂O₃Is La₂O₃、Gd₂O₃、Y₂O₃、Yb₂O₃One or more of (a).

Further, the optical glass comprises the following components in percentage by weight: BaO/RO is 0.8-1.0; and/or TiO₂/SiO₂0.4 to 0.7; and/or B₂O₃/SiO₂Is 0.1 or less; and/or Na₂O/(Na₂O+K₂O) is 0.4 to 0.8; and/or Nb₂O₅/TiO₂Is 0.2 or less, wherein RO is the total content of BaO, SrO, CaO and MgO.

Further, the optical glass comprises the following components in percentage by weight: TiO 2₂/SiO₂0.45 to 0.6; and/or B₂O₃/SiO₂Is 0.05 or less; and/or Na₂O/(Na₂O+K₂O) is 0.5 to 0.75; and/or Nb₂O₅/TiO₂Is 0.1 or less.

Further, the above optical glass does not contain Li in its components₂O; and/or does not contain ZrO₂(ii) a And/or no ZnO; and/or does not contain WO₃(ii) a And/or do not contain B₂O₃。

Further, the above optical glass has a composition in weight percent of TiO₂、SiO₂、Na₂O、K₂The total content of O and BaO is 95% or more, preferably TiO₂、SiO₂、Na₂O、K₂The total content of O and BaO is 97% or more, and TiO is more preferable₂、SiO₂、Na₂O、K₂The total content of O and BaO is 98% or more.

Furthermore, the refractive index nd of the optical glass is 1.62-1.71, preferably 1.63-1.70, and more preferably 1.64-1.69; abbe number v_dIs 28 to 36, preferably 29 to 35, and more preferably 30 to 34.

Further, the stability of the acid resistance of the above optical glass D_AIs 2 or more, preferably 1; and/or water-resistant actionStability D_WIs 2 or more, preferably 1; and/or a density rho of 3.1g/cm³Hereinafter, it is preferably 3.0g/cm³Hereinafter, more preferably 2.95g/cm³The following; and/or coefficient of thermal expansion alpha_-30/70℃Is 98 x 10^-7Preferably 95X 10 or less,/K^-7A value of less than or equal to K, more preferably 90X 10^-7below/K; and/or transition temperature T_gAt 610 ℃ or lower, preferably 600 ℃ or lower, more preferably 595 ℃ or lower; and/or Knoop hardness H_KIs 520X 10⁷Pa or more, preferably 540X 10⁷Pa or more, more preferably 550X 10⁷Pa or above.

The glass preform is made of the optical glass.

And the optical element is made of the optical glass or the glass prefabricated member.

The optical instrument is made of the optical glass or the optical element.

The invention has the beneficial effects that: through reasonable component design and proportion, the optical glass has proper hardness and excellent chemical stability while meeting the expected refractive index and Abbe number, and meets the application requirements in the fields of vehicle-mounted monitoring and security protection and the like.

Detailed Description

The optical glass of the present invention is obtained by the following steps, which are not limited to the above-described embodiments, and can be appropriately modified within the scope of the object of the present invention. Note that, although the description of the duplicate description may be appropriately omitted, the gist of the invention is not limited to this. The optical glass of the present invention may be simply referred to as glass in the following.

[ optical glass ]

The ranges of the respective components of the optical glass of the present invention are explained below. In the present specification, the contents of the respective components are all expressed in terms of weight percentage with respect to the total amount of glass matter converted into the composition of oxides, if not specifically stated. Here, the "composition converted to oxides" means that when oxides, complex salts, hydroxides, and the like used as raw materials of the optical glass composition component of the present invention are decomposed in the melt and converted to oxides, the total amount of the oxides is 100%.

Unless otherwise indicated herein, the numerical ranges set forth herein include upper and lower values, and the terms "above" and "below" include the endpoints, and all integers and fractions within the range, and are not limited to the specific values listed in the defined range. As used herein, "and/or" is inclusive, e.g., "A and/or B," and means A alone, B alone, or both A and B.

< essential Components and optional Components >

SiO₂Is a skeleton of an optical glass, and has the functions of maintaining the chemical stability of the glass and improving the devitrification resistance of the glass as a glass network forming body. When SiO is present₂When the content is less than 41%, the above-mentioned effects are hardly obtained, and therefore SiO₂The lower limit of the content of (b) is 41%, preferably 42%, more preferably 43%; when SiO is present₂When the content of (3) is more than 58%, the glass-melting property is lowered and the transition temperature is raised, so that SiO₂The upper limit of the content of (B) is 58%, preferably 55%, more preferably 50%.

TiO₂Has the functions of improving the refractive index and dispersion of the glass, can participate in the formation of glass network, can lead the glass to be more stable and reduce the viscosity of the glass by introducing proper amount of TiO more than 18 percent₂To obtain the above effects, TiO is preferable₂The lower limit of the content of (b) is 20%, more preferably the lower limit is 22%; but with a large introduction of TiO₂Since the transmittance of the glass in the short wavelength region in the visible light region is lowered and the tendency of the glass to devitrify increases, TiO in the present invention₂The upper limit of the content of (B) is 32%, preferably 30%, more preferably 28%.

In some embodiments of the invention, if TiO₂/SiO₂When the amount is less than 0.35, the glass tends to have a low melting property and a poor striae, and when TiO is used, the glass tends to have a poor striae₂/SiO₂When the glass content exceeds 0.75, the glass has reduced chemical stability and optical transmittance and increased density, so that the present invention is useful for a glass having a high glass qualityMedium TiO 2₂/SiO₂0.35 to 0.75, preferably TiO₂/SiO₂0.4 to 0.7, more preferably TiO₂/SiO₂0.45 to 0.6.

Na₂O has the function of improving the meltability of the glass, has obvious effect of improving the melting effect and can also reduce the transformation temperature of the glass, and more than 3 percent of Na is introduced into the invention₂O to obtain the above effect, preferably Na₂The lower limit of the content of O is 5%, and more preferably 8%; when Na is present₂The content of O exceeds 18%, the chemical stability and weather resistance of the glass are lowered, and therefore Na₂The upper limit of the content of O is 18%, preferably 16%, more preferably 14%.

K₂O has the function of improving the thermal stability and the melting property of the glass, and more than 2 percent of K is introduced into the glass₂O to obtain the above effect, preferably K₂The lower limit of the content of O is 3%, and K is more preferable₂The lower limit of the content of O is 4%; but when K₂When the content of O exceeds 15%, the glass has a reduced devitrification resistance, so that K is contained₂The upper limit of the content of O is 15%, preferably 12%, more preferably 10%.

In some embodiments of the invention, if Na₂O/(Na₂O+K₂O) less than 0.3, the glass becomes poor in devitrification resistance, and Na or Na₂O/(Na₂O+K₂O) exceeding 0.85 decreases the thermal stability and striae of the glass, so Na is preferred₂O/(Na₂O+K₂O) is 0.3 to 0.85, more preferably Na₂O/(Na₂O+K₂O) is 0.4 to 0.8. In some embodiments, by controlling Na₂O/(Na₂O+K₂O) is in the range of 0.5 to 0.75, and the thermal expansion coefficient of the glass can be improved, so Na is more preferable₂O/(Na₂O+K₂O) is 0.5 to 0.75.

Li₂O can lower the glass transition temperature, but its content is high, which is disadvantageous in acid resistance stability and thermal expansion coefficient of the glass, and in corrosion of a melting vessel (e.g., platinum crucible), therefore, Li₂The content of O is preferably 5% or less, more preferably 3% or lessMore preferably 2% or less. In some embodiments, even small amounts of Li are present₂O, which also causes the thermal expansion coefficient of the glass to exceed the design requirements and the devitrification resistance to deteriorate, is more preferably not containing Li₂O。

MgO can reduce the refractive index and melting temperature of the glass, but when the MgO is added excessively, the refractive index of the glass cannot meet the design requirement, the devitrification resistance and stability of the glass are reduced, and the cost of the glass is increased. Therefore, the MgO content is limited to 0 to 10%, preferably 0 to 5%, and more preferably 0 to 3%.

CaO is useful for adjusting the optical constants of the glass and improving the processability of the glass, but when added in an excessive amount, the optical data of the glass is not satisfactory and the devitrification resistance is deteriorated. Therefore, the content of CaO is limited to 0 to 10%, preferably 0 to 5%, more preferably 0 to 3%, and further preferably no CaO is introduced.

The addition of SrO to glass makes it possible to adjust the refractive index and abbe number of the glass, but if the addition amount is too large, the chemical stability of the glass decreases and the cost of the glass rapidly increases. Therefore, the SrO content is limited to 0 to 10%, preferably 0 to 5%, and more preferably 0 to 3%.

BaO is an essential component for adjusting the refractive index of the glass, improving the transmittance and strength of the glass in the present invention, and the effect is not significant when the content thereof is less than 2%, preferably the lower limit of the content of BaO is 3%, more preferably the lower limit of the content of BaO is 5%; however, if the content exceeds 15%, the devitrification resistance and chemical stability of the glass are deteriorated. Therefore, the upper limit of the BaO content is 15%, preferably 12%, more preferably 11%.

In the present invention, by controlling BaO/RO to 0.5 or more, the glass of the present invention has high hardness while having excellent chemical stability, wherein RO is the total content of BaO, SrO, CaO and MgO. Therefore, the range of BaO/RO is 0.5 to 1.0, preferably 0.7 to 1.0, and in some embodiments of the present invention, the striae of the glass can also be improved by more preferably 0.8 to 1.0.

Nb₂O₅Is highA refractive high-dispersion component, which is an optional component in the present invention, by controlling Nb₂O₅When the content of (2) is 8% or less, the deterioration of devitrification resistance of the glass can be suppressed. Therefore, Nb in the optical glass of the present invention₂O₅The content of (b) is 8% or less, preferably 6% or less, more preferably 3% or less. In some embodiments, by not containing Nb₂O₅The transmittance and anti-devitrification performance of the glass can be improved.

In some embodiments of the invention, the Nb is modified by₂O₅/TiO₂The optical transmittance and glass forming stability of the glass can be improved and the chemical stability of the glass can be optimized by controlling the content of Nb below 0.3, preferably Nb₂O₅/TiO₂Is 0.2 or less, and Nb is more preferable₂O₅/TiO₂Is 0.1 or less.

Al₂O₃The chemical stability of the glass can be improved to some extent, but the content thereof is too large, and the resistance to devitrification and melting of the glass are lowered, so that the content thereof is 5% or less, preferably 3% or less, and more preferably 1% or less.

B₂O₃Has an effect of improving the meltability of the glass, but when the content thereof is more than 10%, the chemical stability and devitrification resistance of the glass are lowered. Thus, in the present invention B₂O₃The upper limit of the content of (B) is 10%, preferably 5%, more preferably 3%. In some embodiments, by not introducing B₂O₃The desired chemical stability can be obtained.

In some embodiments of the invention, if B₂O₃/SiO₂If it exceeds 0.15, the chemical stability and devitrification resistance of the glass are lowered and the optical transmittance is deteriorated, so that B₂O₃/SiO₂Is 0.15 or less, preferably 0.1 or less, and more preferably 0.05 or less.

Ln₂O₃Is a component for improving the refractive index and chemical stability of the glass, is an optional component in the optical glass of the present invention, wherein Ln₂O₃Is La₂O₃、Gd₂O₃、Y₂O₃、Yb₂O₃One or more of (a). By mixing Ln₂O₃The content of (b) is controlled to 5% or less, whereby the devitrification resistance of the glass can be improved and a desired refractive index and Abbe number can be obtained. Thus, in the optical glass of the present invention, Ln₂O₃The upper limit of the content range is 5%, preferably 3%, more preferably 1%.

ZnO is added into the glass of the system of the invention, the refractive index and dispersion of the glass can be adjusted, the transition temperature of the glass is reduced, but when the content of ZnO exceeds 5 percent, the devitrification resistance of the glass is reduced, meanwhile, the high-temperature viscosity is smaller, the forming is difficult, and the thermal expansion coefficient and the refractive index temperature coefficient of the glass are increased. Therefore, in the present invention, the ZnO content is 0 to 5%, preferably 0 to 3%, more preferably 0 to 1%, and further preferably not contained.

ZrO₂Is a component having an increased refractive index, and when the content thereof is large, the devitrification resistance of the glass is lowered, and ZrO in the present invention₂The content of (b) is 5% or less, preferably 3% or less, more preferably 2% or less, and further preferably not incorporated.

By adding 0-1% of Sb₂O₃、SnO₂SnO and CeO₂One or more components in the glass can be used as a clarifying agent to improve the clarifying effect of the glass, and 0-0.5% of the clarifying agent is preferably added. But when Sb is₂O₃When the content exceeds 1%, the glass tends to have a reduced fining property and the deterioration of the forming mold is promoted by the strong oxidation thereof, so that Sb in the present invention is₂O₃The amount of (B) is 1% or less, preferably 0.5% or less. SnO₂SnO may be added as a fining agent, but when the content exceeds 1%, the glass is colored, or when the glass is heated, softened and press-molded again, Sn tends to become a starting point of nucleation and devitrification occurs, so that the SnO of the present invention₂And SnO are contained in an amount of 1% or less, preferably 0.5% or less, and more preferably not contained. CeO (CeO)₂Action and addition amount ratio of (B) and SnO₂The content is 1% or less, preferably 0.5% or less, and more preferablyAnd (4) selecting the materials not to contain.

In order to obtain the desired hardness of the glass of the present invention while the glass is excellent in chemical stability and optical transmittance and low in transition temperature and thermal expansion coefficient, TiO is preferable₂、SiO₂、Na₂O、K₂The total content of O and BaO is 95% or more, and TiO is more preferable₂、SiO₂、Na₂O、K₂The total content of O and BaO is 97% or more, and TiO is more preferable₂、SiO₂、Na₂O、K₂The total content of O and BaO is 98% or more.

Other components not mentioned above, such as P, can be added as necessary within the range not impairing the characteristics of the glass of the present invention₂O₅、GeO₂、TeO₂、Bi₂O₃、Ta₂O₅And Ga₂O₃The upper limit of the content of the above components, which are contained singly or in combination, is preferably 5%, more preferably 3%, still more preferably 1%, and yet still more preferably not contained. In some embodiments, WO₃Since the incorporation of (A) causes deterioration in devitrification resistance and coloring degree of the glass, WO is preferably not contained₃。

< component which should not be contained >

In the glass of the present invention, even when a small amount of oxides of transition metals such as V, Cr, Mn, Fe, Co, Ni, Cu, Ag, and Mo is contained singly or in combination, the glass is colored and absorbs at a specific wavelength in the visible light region, thereby impairing the property of the present invention to improve the effect of visible light transmittance.

In recent years, oxides of Th, Cd, Tl, Os, Be, and Se tend to Be used as harmful chemical substances in a controlled manner, and measures for protecting the environment are required not only in the glass production process but also in the processing process and disposal after commercialization. Therefore, when importance is attached to the influence on the environment, it is preferable that these components are not substantially contained except for inevitable mixing. Thereby, the optical glass becomes practically free from substances contaminating the environment. Therefore, the optical glass of the present invention can be manufactured, processed, and discarded without taking special measures for environmental countermeasures.

In order to achieve environmental friendliness, the optical glass of the present invention does not contain As₂O₃And PbO. Although As₂O₃Has the effects of eliminating bubbles and better preventing the glass from coloring, but As₂O₃The addition of (b) increases the platinum attack of the glass on the furnace, particularly on the platinum furnace, resulting in more platinum ions entering the glass, which adversely affects the service life of the platinum furnace.

The term "not introduced", "not containing" or "0%" as used herein means that the compound, molecule or element is not intentionally added as a raw material to the optical glass of the present invention; however, it is within the scope of the present invention that certain impurities or components which are not intentionally added may be present as raw materials and/or equipment for producing the optical glass and may be contained in the final optical glass in small or trace amounts.

The performance of the optical glass of the present invention will be described below.

< refractive index and Abbe number >

Refractive index (nd) and Abbe number (. nu.) of optical glass_d) The test was carried out according to the method specified in GB/T7962.1-2010.

The refractive index (nd) of the optical glass is 1.62-1.71, preferably 1.63-1.70, more preferably 1.64-1.69; abbe number v_dIs 28 to 36, preferably 29 to 35, and more preferably 30 to 34.

< stability against acid Effect >

Stability of acid resistance of optical glasses (D)_A) (powder method) the test was carried out according to the method prescribed in GB/T17129.

Stability of acid resistance of the optical glass of the present invention (D)_A) Is 2 or more, preferably 1.

< stability against Water action >

Stability to Water of optical glass (D)_W) (powder method) according to GB/T17129 the method specified.

Stability to Water action of the optical glass of the invention (D)_W) Is 2 or more, preferably 1.

< Density >

The density (. rho.) of the optical glass was measured according to the method specified in GB/T7962.20-2010.

The optical glass of the present invention has a density (. rho.) of 3.1g/cm³Hereinafter, it is preferably 3.0g/cm³Hereinafter, more preferably 2.95g/cm³The following.

< coefficient of thermal expansion >

Coefficient of thermal expansion (alpha) of optical glass_-30/70℃) And testing data at-30-70 ℃ according to a method specified in GB/T7962.16-2010.

The coefficient of thermal expansion (. alpha.) of the optical glass of the present invention_-30/70℃) Is 98 x 10^-7Preferably 95X 10 or less,/K^-7A value of less than or equal to K, more preferably 90X 10^-7and/K is less than or equal to.

< transition temperature >

Transition temperature (T) of optical glass_g) The test was carried out according to the method specified in GB/T7962.16-2010.

Transition temperature (T) of the optical glass of the present invention_g) Is 610 ℃ or lower, preferably 600 ℃ or lower, and more preferably 595 ℃ or lower.

< degree of coloration >

Coloring degree (. lamda.) for short-wave transmission spectral characteristics of the glass of the present invention₈₀And λ₅) And (4) showing. Lambda [ alpha ]₈₀It refers to the wavelength corresponding to the glass transmittance of 80%. Lambda [ alpha ]₈₀Was measured using a glass having a thickness of 10. + -. 0.1mm with two opposing planes parallel to each other and optically polished, measuring the spectral transmittance in the wavelength region from 280nm to 700nm and showing a wavelength of transmittance of 80%. The spectral transmittance or transmittance is the intensity I of light incident perpendicularly to the surface of the glass_inLight transmitted through the glass and having an intensity I emitted from a plane_outIn the case of light of (1) through (I)_out/I_inThe amount of (A) and also the transmission of the surface reflection losses on the above-mentioned surface of the glass. The higher the refractive index of the glass, the greater the surface reflection loss. Thus, in high refractive index glasses, λ₈₀A small value of (a) means that the glass itself is colored very little.

Optical glass lambda of the present invention₈₀Less than or equal to 410nm, preferably lambda₈₀Is less than or equal to 405 nm; lambda [ alpha ]₅Less than or equal to 370nm, preferably lambda₅Less than or equal to 365 nm.

< Knoop hardness >

Knoop hardness (H) of optical glass_K) The test was carried out according to the test method specified in GB/T7962.18-2010.

Knoop hardness (H) of the optical glass of the present invention_K) Is 520X 10⁷Pa or more, preferably 540X 10⁷Pa or more, more preferably 550X 10⁷Pa or above.

< degree of bubbling >

The bubble degree of the optical glass is tested according to the method specified in GB/T7962.8-2010.

The optical glass of the present invention has a bubble degree of B class or more, preferably A class or more, more preferably A class₀More than grade.

[ production method ]

The method for manufacturing the optical glass comprises the following steps: the glass is produced by adopting conventional raw materials and conventional processes, carbonate, nitrate, sulfate, hydroxide, oxide and the like are used as raw materials, the materials are mixed according to a conventional method, the mixed furnace burden is put into a smelting furnace at 1150-1350 ℃ for smelting, and after clarification, stirring and homogenization, homogeneous molten glass without bubbles and undissolved substances is obtained, and the molten glass is cast in a mold and annealed. Those skilled in the art can appropriately select the raw materials, the process method and the process parameters according to the actual needs.

Glass preform and optical element

The glass preform can be produced from the optical glass produced by, for example, grinding or press molding such as reheat press molding or precision press molding. That is, the glass preform may be produced by machining the optical glass by grinding, polishing, or the like, or by producing a preform for press molding from the optical glass, subjecting the preform to reheat press molding, and then polishing, or by precision press molding the preform obtained by polishing.

It should be noted that the means for producing the glass preform is not limited to the above means. As described above, the optical glass of the present invention is useful for various optical elements and optical designs, and among them, it is particularly preferable to form a preform from the optical glass of the present invention, and use the preform for reheat press forming, precision press forming, or the like to produce optical elements such as lenses, prisms, or the like.

The glass preform of the present invention and the optical element are each formed of the above-described optical glass of the present invention. The glass preform of the present invention has excellent characteristics possessed by optical glass; the optical element of the present invention has excellent characteristics of optical glass, and can provide optical elements such as various lenses and prisms having high optical values.

Examples of the lens include various lenses such as a concave meniscus lens, a convex meniscus lens, a double convex lens, a double concave lens, a plano-convex lens, and a plano-concave lens, each of which has a spherical or aspherical lens surface.

[ optical instruments ]

The optical element formed by the optical glass can be used for manufacturing optical instruments such as photographic equipment, camera equipment, display equipment, monitoring equipment and the like.

Examples

< example of optical glass >

In order to further clarify the explanation and explanation of the technical solution of the present invention, the following non-limiting examples are provided.

In this example, optical glasses having compositions shown in tables 1 to 2 were obtained by the above-mentioned method for producing optical glasses. The characteristics of each glass were measured by the test method described in the present invention, and the measurement results are shown in tables 1 to 2.

TABLE 1

TABLE 2

< glass preform example >

Various lenses such as a concave meniscus lens, a convex meniscus lens, a biconvex lens, a biconcave lens, a plano-convex lens and a plano-concave lens, and preforms such as prisms were produced from the glasses obtained in examples 1 to 20 of optical glass by means of polishing or press molding such as reheat press molding and precision press molding.

< optical element example >

The preforms obtained in the above examples of glass preforms were annealed to reduce the deformation in the glass and to fine-tune the optical properties such as refractive index to desired values.

Next, each preform is ground and polished to produce various lenses such as a concave meniscus lens, a convex meniscus lens, a biconvex lens, a biconcave lens, a plano-convex lens, and a plano-concave lens, and prisms. The surface of the resulting optical element may be coated with an antireflection film.

< optical Instrument example >

The optical element obtained by the above-described optical element embodiment is used for, for example, imaging devices, sensors, microscopes, medical technologies, digital projection, communications, optical communication technologies/information transmission, optics/lighting in the automobile field, photolithography, excimer lasers, wafers, computer chips, and integrated circuits and electronic devices including such circuits and chips, or for image pickup devices and apparatuses in the vehicle-mounted field, by forming an optical component or an optical assembly by using one or more optical elements through optical design.

Claims (20)

1. Optical glass, characterized in that its components, expressed in weight percent, contain: SiO 2₂：41～52.6%；TiO₂：18～32%；Na₂O：3～18%；K₂O：2～15%；BaO：3～15%；SrO：0～5%；CaO：0～5%；MgO：0～5%；Nb₂O₅: 0 to 5%, wherein BaO/RO is 0.887 to 1.0, TiO₂/SiO₂0.35 to 0.573, wherein RO is the total content of BaO, SrO, CaO and MgO, and the refractive index nd is 1.62 to 1.71; TiO 2₂、SiO₂、Na₂O、K₂The total content of O and BaO is more than 95%; na (Na)₂O/（Na₂O+K₂O) is 0.3 to 0.8.

2. The optical glass according to claim 1, wherein the composition, expressed in weight percent, further comprises: b is₂O₃：0～5%；Ln₂O₃：0～5%；ZrO₂：0～5%；Li₂O：0～5%；Al₂O₃: 0 to 5 percent; ZnO: 0 to 5 percent; a clarifying agent: 0 to 1%, wherein Ln₂O₃Is La₂O₃、Gd₂O₃、Y₂O₃、Yb₂O₃One or more of Sb as clarifying agent₂O₃、SnO₂、SnO、CeO₂One or more of (a).

3. Optical glass, characterized in that its components are expressed in weight percent: SiO 2₂：41～52.6%；TiO₂：18～32%；Na₂O：3～18%；K₂O：2～15%；BaO：3～15%；SrO：0～5%；CaO：0～5%；MgO：0～5%；B₂O₃：0～10%；Ln₂O₃：0～5%；Nb₂O₅：0～5%；ZrO₂：0～5%；Li₂O：0～5%；Al₂O₃: 0 to 5 percent; ZnO: 0 to 5 percent; a clarifying agent: 0 to 1% of BaO/RO of 0.887 to 1.0, TiO₂/SiO₂0.35 to 0.573, wherein RO is the total content of BaO, SrO, CaO and MgO, Ln₂O₃Is La₂O₃、Gd₂O₃、Y₂O₃、Yb₂O₃One or more of Sb as clarifying agent₂O₃、SnO₂、SnO、CeO₂One or more of them, the refractive index nd is 1.62-1.71; TiO 2₂、SiO₂、Na₂O、K₂The total content of O and BaO is more than 95%; na (Na)₂O/（Na₂O+K₂O) is 0.3 to 0.8.

4. An optical glass according to any one of claims 1 to 3, wherein the composition is expressed in weight percent, wherein: SiO 2₂: 42-52.6%; and/or TiO₂: 20-30%; and/or Na₂O: 5-16%; and/or K₂O: 3-12%; and/or BaO: 3-12%; and/or Ln₂O₃: 0 to 3 percent; and/or ZrO₂: 0 to 3 percent; and/or Li₂O: 0 to 3 percent; and/or Al₂O₃: 0 to 3 percent; and/or ZnO: 0 to 3 percent; and/or a clarifying agent: 0 to 0.5%, wherein Ln₂O₃Is La₂O₃、Gd₂O₃、Y₂O₃、Yb₂O₃One or more of Sb as clarifying agent₂O₃、SnO₂、SnO、CeO₂One or more of (a).

5. An optical glass according to any one of claims 1 to 3, wherein the composition is expressed in weight percent, wherein: b is₂O₃/SiO₂Is less than 0.15; and/or Nb₂O₅/TiO₂Is 0.3 or less, wherein RO is the total content of BaO, SrO, CaO and MgO.

6. An optical glass according to any one of claims 1 to 3, wherein the composition is expressed in weight percent, wherein: SiO 2₂: 43-50%; and/or TiO₂: 22-28%; and/or Na₂O: 8-14%; and/or K₂O: 4-10%; and/or BaO: 5-11%; and/or SrO: 0 to 3 percent; and/or CaO: 0 to 3 percent; and/or MgO: 0 to 3 percent; and/or B₂O₃: 0 to 3 percent; and/or Ln₂O₃: 0 to 1 percent; and/or Nb₂O₅: 0 to 3 percent; and/or ZrO₂: 0-2%; and/or Li₂O: 0-2%; and/or Al₂O₃: 0 to 1 percent; and/or ZnO: 0 to 1 percent; and/or Sb₂O₃: 0 to 0.5%, wherein Ln₂O₃Is La₂O₃、Gd₂O₃、Y₂O₃、Yb₂O₃One or more of (a).

7. An optical glass according to any one of claims 1 to 3, wherein the composition is expressed in weight percent, wherein: TiO 2₂/SiO₂0.4 to 0.573; and/or B₂O₃/SiO₂Is 0.1 or less; and/or Na₂O/（Na₂O+K₂O) is 0.4 to 0.8; and/or Nb₂O₅/TiO₂Is 0.2 or less, wherein RO is the total content of BaO, SrO, CaO and MgO.

8. An optical glass according to any one of claims 1 to 3, wherein the composition is expressed in weight percent, wherein: TiO 2₂/SiO₂0.45 to 0.573; and/or B₂O₃/SiO₂Is 0.05 or less; and/or Na₂O/（Na₂O+K₂O) is 0.5 to 0.75; and/or Nb₂O₅/TiO₂Is 0.1 or less.

9. An optical glass according to any of claims 1 to 3, characterised in thatIn that the components thereof do not contain Li₂O; and/or does not contain ZrO₂(ii) a And/or no ZnO; and/or does not contain WO₃(ii) a And/or do not contain B₂O₃。

10. An optical glass according to any one of claims 1 to 3, characterised in that its composition, expressed in weight percentage, is TiO₂、SiO₂、Na₂O、K₂The total content of O and BaO is 97% or more.

11. An optical glass according to any one of claims 1 to 3, characterised in that its composition, expressed in weight percentage, is TiO₂、SiO₂、Na₂O、K₂The total content of O and BaO is 98% or more.

12. The optical glass according to any one of claims 1 to 3, wherein the Abbe number v of the optical glass_dIs 28 to 36.

13. An optical glass according to any one of claims 1 to 3, wherein the optical glass has a refractive index nd of 1.63 to 1.70; abbe number v_dIs 29 to 35.

14. An optical glass according to any one of claims 1 to 3, wherein the optical glass has a refractive index nd of 1.64 to 1.69; abbe number v_dIs 30 to 34.

15. The optical glass according to any one of claims 1 to 3, wherein the optical glass has an acid-resistance stability D_AIs more than 2 types; and/or stability against water action D_WIs more than 2 types; and/or a density rho of 3.1g/cm³The following; and/or coefficient of thermal expansion alpha_-30/70℃Is 98 x 10^-7below/K; and/or transition temperature T_gBelow 610 ℃; and/or Knoop hardness H_KIs 520X 10⁷Pa or above.

16. The optical glass according to any one of claims 1 to 3, wherein the optical glass has an acid-resistance stability D_AIs of type 1; and/or stability against water action D_WIs of type 1; and/or a density rho of 3.0g/cm³The following; and/or coefficient of thermal expansion alpha_-30/70℃Is 95X 10^-7below/K; and/or transition temperature T_gBelow 600 ℃; and/or Knoop hardness H_KIs 540X 10⁷Pa or above.

17. The optical glass according to any one of claims 1 to 3, wherein the optical glass has a density p of 2.95g/cm³The following; and/or coefficient of thermal expansion alpha_-30/70℃Is 90X 10^-7below/K; and/or transition temperature T_gBelow 595 ℃; and/or Knoop hardness H_KIs 550 multiplied by 10⁷Pa or above.

18. A glass preform made of the optical glass according to any one of claims 1 to 17.

19. An optical element produced from the optical glass according to any one of claims 1 to 17 or the glass preform according to claim 18.

20. An optical device comprising the optical glass according to any one of claims 1 to 17 or the optical element according to claim 19.