TWI729505B - Fluorophosphate optical glass, optical preforms, components and instruments - Google Patents

Abstract

The invention provides a fluorophosphate optical glass, an optical preform, an element and an instrument, belonging to the technical field of optical glass. The optical glass contains P ⁵⁺ : 2-20%, Al ³⁺ : 20-40%, Ba ²⁺ : 0.5-10%, Sr ²⁺ : 5-25%, Ca ²⁺ : cation molar percentage. ^{15-35%, Mg 2+: 1-15%} ; anion mole percent, containing ^{F -: 83-95%, O 2-} : 5-17%. The refractive index (nd) of the fluorophosphate optical glass of the present invention is 1.42-1.45, the Abbe number (vd) is 93-96, the density (ρ) is 3.55 g/cm ³ or less, the bubble degree is above grade B, and the thermal expansion coefficient (Α _{20 ℃ -120 ℃} ) is 160×10 ^-7 /K or less, water resistance stability (D _W ) is class 2 or more, and anti-crystallization performance is excellent.

Description

Fluorophosphate optical glass, optical preforms, components and instruments

The invention belongs to the technical field of optical glass, and is specifically a fluorophosphate optical glass, an optical preform, an element and an instrument.

Fluorophosphate optical glass is a new type of glass material with low refractive index and low dispersion. It can eliminate the special dispersion of the secondary spectrum in the optical system, improve the resolution, improve the imaging quality of the optical system, and also has low softening characteristics. It can be directly precision molded into an aspheric lens, which can better eliminate chromatic aberration, spherical aberration, aberration, and reduce system volume and weight.

At present, fluorophosphate optical glass has been widely used in high-precision, high-resolution optical instrument combination lenses such as digital cameras, high-quality surveillance, astronomical telescopes, etc., and has become a new type of optoelectronic material with potential market prospects. Specific applications in these fields have put forward higher requirements for the performance of fluorophosphate optical glasses. In the existing published literature, there have been reports of fluorophosphate optical glasses with an Abbe number of 80 or more, but these fluorophosphates Optical glass has high density, poor chemical stability and crystallization resistance, high thermal expansion coefficient, low bubble degree, and it is easy to cause damage during molding and heating.

The purpose of the present invention is to provide a fluorophosphate optical glass, optical preforms, components and instruments with a refractive index (nd) of 1.42-1.45 and an Abbe number (vd) of 93-96. The fluorophosphate optical glass of the present invention has low density, excellent chemical stability and anti-crystallization performance, low thermal expansion coefficient, is not easy to be damaged by molding and thermal processing, has a high bubble degree, and can realize stable mass production.

The objective of the present invention is achieved by the following technical solutions: fluorophosphate optical glass, the cations contain P ⁵⁺ , Al ³⁺ and alkaline earth metal ions, the anions contain F ^- and O ^2- ; the thermal expansion coefficient of the optical glass (α _{20 ℃ -120 ℃} ) is 160×10 ^-7 /K or less; density (ρ) is 3.55 g/cm ³ or less; water resistance stability (D _W ) is class 2 or more.

Further, it contains P ⁵⁺ : 2-20%, Al ³⁺ : 20-40%, Ba ²⁺ : 0.5-10%, Sr ²⁺ : 5-25%, Ca ²⁺ : 15. ^{-35%, Mg 2+: 1-15%} ; anion mole percent, containing ^{F -: 83-95%, O 2-} : 5-17%.

Fluorophosphate optical glass, containing P ⁵⁺ : 2-20%, Al ³⁺ : 20-40%, Ba ²⁺ : 0.5-10%, Sr ²⁺ : 5-25%, Ca ^{2 in terms of cation mole percentage +} : 15-35%, Mg ²⁺ : 1-15%; in terms of anion mole percentage, it contains F ^- : 83-95%, O ^2- : 5-17%.

Further, it also contains Ln ³⁺ :0-6%, Na ⁺ :0-10%, Li ⁺ :0-10%, K ⁺ :0-10%, where Ln ³⁺ is La ³⁺ , Gd ³⁺ One or more of, Y ³⁺ and Yb ^3+.

Fluorophosphate optical glass is composed of P ⁵⁺ : 2-20%, Al ³⁺ : 20-40%, Ba ²⁺ : 0.5-10%, Sr ²⁺ : 5-25%, Ca ^{2 in terms of cation mole percentage +} : 15-35%, Mg ²⁺ : 1-15%, Na ⁺ : 0-10%, Li ⁺ : 0-10%, K ⁺ : 0-10%, Ln ³⁺ : 0-6% composition, LN ³⁺ is La ^3+, in ³⁺ one or more of Gd ^3+, Y ³⁺ and Yb, anionic mole percent, the ^{F -: 83-95%, O 2-} : 5-17% composition .

Further, the refractive index (nd) of the glass is 1.42-1.45, preferably 1.43-1.44; the Abbe number (vd) is 93-96, preferably 94-95.5.

Further, wherein: P ⁵⁺ : 3-15%, and/or Al ³⁺ : 25-38%, and/or Ba ²⁺ : 1-8%, and/or Sr ²⁺ : 10-22%, and / Or Ca ²⁺ : 20-33%, and/or Mg ²⁺ : 2-12%, and/or Ln ³⁺ : 0-5%, and/or Na ⁺ : 0-4%, and/or Li ⁺ : 0.5-5%, and/or K ⁺ : 0-5%.

Further, where: Ba ²⁺ /Ca ²⁺ is 0.01-0.155, and/or Ba ²⁺ /(Ca ²⁺ +Mg ²⁺ ) is 0.08-0.13, and/or O ^2- / F ^- is 0.105-0.2 .

Further, wherein: P ⁵⁺ : 5-10%, and/or Al ³⁺ : 30-35%, and/or Ba ²⁺ : 1-5%, and/or Sr ²⁺ : 15-20%, and / Or Ca ²⁺ : 25-30%, and/or Mg ²⁺ : 5-10%, and/or Ln ³⁺ : 0.5-3%, and/or Na ⁺ : 0.5-2%, and/or Li ⁺ : 0.5-3%, and/or K ⁺ : 0-2%.

Further, where: Ba ²⁺ /Ca ²⁺ is 0.05-0.155, and/or Ba ²⁺ /(Ca ²⁺ +Mg ²⁺ ) is 0.09-0.125, and/or O ^2- / F ^- is 0.11-0.18 .

Further, where: Ba ²⁺ /Ca ²⁺ is 0.1-0.15, and/or Ba ²⁺ /(Ca ²⁺ +Mg ²⁺ ) is 0.1-0.12, and/or O ^2- / F ^- is 0.11-0.15 .

Further, wherein: Y ³⁺ :0-5%, preferably 0-4%, more preferably 0.5-3%; La ³⁺ :0-5%, preferably 0-3%, more preferably 0-1 %; Gd ³⁺ : 0-5%, preferably 0-3%, more preferably 0 -1%; Yb ³⁺ : 0-5%, preferably 0-3%, more preferably 0-1%.

Further, wherein: the ^{content of F-} is 85-92%, more preferably 87-91%; the ^{content of O 2-} is 8-15%, more preferably 9-13%.

Furthermore, the thermal expansion coefficient (α _{20 ℃ -120 ℃} ) of the glass is 155×10 ^-7 /K or less; the density (ρ) is 3.53 g/cm ³ or less; the air bubble degree is above grade B, preferably above grade A, more Preferably it is A ₀ grade or higher; Water resistance stability (D _W ) is Class 1 or higher.

An optical preform made of the above-mentioned fluorophosphate optical glass.

An optical element made of the above-mentioned fluorophosphate optical glass and optical preform.

An optical instrument made of the above-mentioned optical components.

Compared with the prior art, the present invention has the following beneficial effects:

Through reasonable component design, the fluorophosphate optical glass of the present invention has excellent chemical stability, anti-crystallization performance, thermal expansion coefficient and bubble degree. The refractive index (nd) of the fluorophosphate optical glass of the present invention is 1.42-1.45, Abbe number (vd) is 93-96, thermal expansion coefficient (α _{20 ℃ -120 ℃} ) is 160×10 ^-7 /K or less; density (ρ) is 3.55 g/cm ³ or less; air bubbles are above grade B; water resistance The action stability (D _W ) is more than class 2.

In order to make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, but not used to limit the present invention.

The functions and limits of the components contained in the fluorophosphate optical glass of the present invention will be explained in detail below in combination with specific principles.

It should be noted that in this specification, the total content of each cationic component and cationic component is represented by "cation mole percentage", and the total content of each anion component and anion component is represented by "anion mole percentage". "Cation mole percentage" refers to the percentage of a certain cationic component to the total cation mole content, and "anion mole percentage" refers to the percentage of a certain anion component to the total anion mole content.

It should be noted that the ion valence of each component is only a representative value used for convenience, and there is no difference from other ion valences. There is a possibility that the ion valence of each component present in the optical glass is outside the representative value. For example, P is usually present in glass with an ionic valence of 5, so "P ⁵⁺ "is used as a representative in this specification, but there is a possibility that it exists in a state of other ionic valences, and it is also in the present invention. Within the scope of protection.

P ⁵⁺ is an important component that functions as a network structure in fluorophosphate optical glass. It ^{forms the main element of the glass skeleton together with O 2-} , which can effectively improve the mechanical properties of the glass while maintaining the stability of the glass. In the fluorophosphate optical glass of the present invention, when ^{the content of P 5+} is less than 2%, the crystallizing tendency of the glass is increased, and the stability becomes worse; when ^{the content of P 5+} is higher than 20%, the glass will be damaged. The performance has a great impact, and it is difficult to obtain the optical constants required by the present invention. Therefore, in order to balance the stability and optical properties of the glass, ^{the content of P 5+} is limited to 2-20%, preferably 3-15%, and more preferably 5-10%.

Al ³⁺ is an important component in fluorophosphate optical glass for improving devitrification resistance and chemical stability. When its content is less than 20%, the chemical stability of the glass is reduced, so the lower limit is 20%, preferably 25% , More preferably 30%; when the content is higher than 40%, the required refractive index and Abbe number will not be obtained due to the reduction of the content of other components. At the same time, the glass transition temperature Tg will rise significantly, resulting in an increase in the molding temperature. The tendency of opacification increases, brittleness increases, and abrasion degree increases. Therefore, the ^{upper limit of the content of Al 3+} is 40%, preferably 38%, more preferably 37%, still more preferably 36%, and still more preferably 35% .

The main function of alkaline earth metals such as Ba ²⁺ , Sr ²⁺ , Ca ²⁺ , Mg ²⁺ is to improve the chemical stability and anti-crystallization performance of the glass, so that the glass can achieve the expected optical performance, and control the refractive index and Abbe number. At the same time, the production process of optical glass can be optimized.

Specifically, Ba ^{2+ is} beneficial to improve the devitrification resistance and refractive index of the glass. When its content is less than 0.5%, the chemical stability and devitrification resistance of the glass become worse; when the content is higher than 10%, it will not reach To the required refractive index and Abbe number, it will increase the specific gravity of the glass at the same time. Therefore, ^{the content of Ba 2+} is limited to 0.5-10%, preferably 1-8%, more preferably 1-5%.

Sr ^{2+ is} effective in improving the devitrification resistance of glass, and can effectively adjust the refractive index and specific gravity of the glass. If the content is too large, the refractive index and dispersion of the glass will increase, making it difficult to achieve the expected optical properties. Reduce the chemical stability of the glass. Therefore, in order to obtain better optical performance, ^{the content of Sr 2+} is limited to 5-25%, preferably 10-22%, more preferably 15-20%.

Ca ²⁺ can reduce the Abbe number and specific gravity of the glass, stabilize the formation of glass, and improve the acid resistance and abrasion resistance of the glass. If its content is too low, the required optical performance cannot be achieved, and if the content is too high, the glass will resist devitrification And the chemical stability deteriorates. Therefore, ^{the content of Ca 2+} is limited to 15-35%, preferably 20-33%, and more preferably 25-30%.

Mg ²⁺ has the effect of improving the thermal stability and grinding resistance of glass. It is added to effectively improve the glass forming, devitrification resistance and processability of the glass. If its content is too low, the processability adjustment is lower, increasing The glass is difficult to process. If the content is too high, the content of other alkaline earth metals will decrease, and the required optical properties will not be achieved. Therefore, ^{the content of Mg 2+} is limited to 1-15%, preferably 2-12%, and more preferably 5-10%.

Regarding the types of alkaline earth metals added and the content of each component, the inventor found that when four alkaline earth metals (Ba ²⁺ , Sr ²⁺ , Ca ²⁺ , Mg ²⁺ ) are added synergistically, the performance of the glass can be adjusted together. In order to obtain the refractive index and Abbe number of the fluorophosphate optical glass of the present invention, the glass has good chemical stability (including water resistance stability and acid resistance stability), air bubble level and anti-crystallization performance, while molding And heating is not easy to damage, reducing the difficulty of production process.

Further, the inventor found in the research that ^{the ratio of Ba 2+} /Ca ²⁺ and Ba ²⁺ /(Ca ²⁺ + Mg ²⁺ ) has an effect on the density, bubble degree, chemical stability and anti-crystallization performance of the glass. Great influence. When ^{the ratio of Ba 2+} /Ca ²⁺ is higher than 0.155, the specific gravity of the glass increases, making it difficult to achieve the purpose of lightening; when ^{the ratio of Ba 2+} /Ca ²⁺ is lower than 0.01, the glass is prone to bubbles. Decreased resistance to crystallization. Therefore, in order to balance the addition of Ba ²⁺ and Ca ²⁺ , reduce the density of the glass, improve the bubble degree and the anti-devitrification performance, the Ba ²⁺ /Ca ^{2+ is} limited to 0.01-0.155, preferably 0.03-0.155, It is more preferably 0.05 to 0.155, and still more preferably 0.1 to 0.15.

When ^{the ratio of Ba 2+} /(Ca ²⁺ + Mg ²⁺ ) is higher than 0.13, ^{the addition amount of Ba 2+} , Ca ²⁺ , Mg ²⁺ is unbalanced, and the glass specific gravity increases; when Ba ²⁺ /( When ^{the ratio of Ca 2+} + Mg ²⁺ ) is lower than 0.08, the chemical stability of the glass will deteriorate and the anti-crystallization performance will decrease. Therefore, in order to reduce the density of the glass and improve the chemical stability and devitrification resistance of the glass, the Ba ²⁺ /(Ca ²⁺ + Mg ²⁺ ) is limited to 0.08-0.13, preferably 0.09-0.125, more preferably 0.1- 0.12.

Alkali metals Li ⁺ , Na ⁺ and K ⁺ can reduce the viscosity of glass, the transition temperature of glass and make it easier to make glass components, but too much introduction will reduce the stability, resulting in an increase in the thermal expansion coefficient of the glass and a decrease in water resistance stability. Therefore, ^{the content of Na +} is limited to 0-10%, preferably 0-4%, more preferably 0.5-2%; Li ^{+ is} limited to 0-10%, preferably 0.5-5%, more preferably 0.5 -3%; ^{the content of K +} is limited to 0-10%, preferably 0-5%, more preferably 0-2%, and further preferably not introduced.

Ln ³⁺ (La ³⁺ , Gd ³⁺ , Yb ³⁺ , Y ³⁺ ), as a rare earth element, is a component that maintains the low dispersion of glass and increases the refractive index. The content is too high to achieve the above effects, but excessive Addition will cause the refractive index of the glass to exceed the required range, and at the same time will increase the melting temperature and reduce the chemical stability of the glass. Therefore, the total content of the rare earth element Ln ³⁺ is limited to 0-6%, preferably 0-5%, more preferably 0.5-3%. Wherein Y ³⁺ :0-5%, preferably 0-4%, more preferably 0.5-3%; La ³⁺ :0-5%, preferably 0-3%, more preferably 0-1%; Gd ³⁺ : 0-5%, preferably 0-3%, more preferably 0-1%; Yb ³⁺ : 0-5%, preferably 0-3%, more preferably 0-1%.

Within the range that does not damage the characteristics of the glass of the present invention, 0-5% other cationic components not mentioned above can be added as needed, such as Si ⁴⁺ , B ³⁺ , Ti ⁴⁺ , Nb ⁵⁺ , W ⁶⁺ , Zr ⁴⁺ , Zn ²⁺ , Ge ⁴⁺ , Te ⁴⁺ , Ce ⁴⁺ , Sb ³⁺ and Sn ⁴⁺ etc. However, even if the transition metal components such as V, Cr, Mn, Fe, Co, Ni, Cu, Ag, and Mo are contained in small amounts individually or in combination, the glass will be colored and absorb at a specific wavelength in the visible light region. As a result, the property of the present invention to improve the visible light transmittance effect is weakened. Therefore, it is preferable that the optical glass that requires the transmittance of wavelengths in the visible light region is not actually included.

The cations of Pb, Th, Cd, Tl, Os, Be, and Se have been used as harmful chemical substances in recent years and have tended to be controlled and used not only in the glass manufacturing process, until the processing process and the disposal after commercialization. The measures are required. Therefore, in the case of attaching importance to the impact on the environment, it is preferable not to actually contain them except for unavoidable mixing. As a result, the optical glass does not actually contain substances that pollute the environment. Therefore, even if no special environmental countermeasures are taken, the optical glass of the present invention can be manufactured, processed, and discarded.

Next, the anion component will be described in detail.

In the fluorophosphate optical glass of the present invention, O ^2- and F ^- are anionic components, which are added to achieve the required optical performance and glass stability.

Specifically, F ^- is a key component for low dispersion and anomalous dispersion of glass. It is effective in reducing the temperature coefficient of refractive index and Tg. If its content is too low, it will be difficult to achieve the required performance; if its content is too high, it will weaken chemical stability of the glass, increasing the thermal expansion coefficient and abrasiveness, especially in the melting process, F ^- volatile will not only pollute the environment, and that the internal composition of the glass will uneven, resulting in defects such as streaks and abnormal data. Therefore, ^{the content of F-} is limited to 83-95%, preferably 85-92%, more preferably 87-91%.

O ^2- is a necessary component to form the network structure of fluorophosphate optical glass. If its content is too low, the glass has poor stability and it is difficult to achieve the required refractive index of the present invention. If its content is too high, it is difficult to obtain the required dispersion and anomalous dispersion. Therefore, ^{the content of O 2-} is limited to 5-17%, preferably 8-15%, and more preferably 9-13%.

The inventor found in the research that the molar content ratio of ^{O 2-} and F ^{- O 2-} / F ^- has a great influence on the thermal expansion coefficient, moldability and glass forming performance of fluorophosphate optical glass. When O ^2- / F ^When the ratio of-is lower than 0.105, the thermal expansion coefficient of the glass is higher and the molding performance is poor. When ^{the ratio of O 2-} / F ^- is higher than 0.2, it is not conducive to the glass forming performance. Therefore, in order to reduce the thermal expansion coefficient of glass, make molding and thermal processing difficult to break, and improve glass forming performance, ^{the ratio of O 2-} / F ^- is limited to 0.105-0.2, preferably 0.11-0.18, and more preferably 0.11-0.15.

May contain anions Cl ^-, Cl ^- form can be introduced into a chloride of a cation, preferably in the form of BaCl ₂ is introduced, in the present invention, as a fining agent, in an amount of 0-1%.

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

The refractive index (nd) and Abbe number (vd) are tested in accordance with the GB/T7962.1-2010 test method.

The coefficient of thermal expansion (α _{20 ℃ -120 ℃} ) is tested in accordance with the GB/T7962.16-2010 test method.

The density (ρ) is tested in accordance with the GB/T7962.20-2010 test method.

The degree of air bubbles is tested in accordance with the GB/T7962.8-2010 test method.

The water resistance stability (D _W ) is tested in accordance with the GB/T17129 test method.

The method for testing the devitrification resistance of the glass in the present invention is as follows: cut the sample glass into a size of 20×20×10mm, put it in a muffle furnace at a temperature of Tg+230℃, and keep it for 30 minutes before taking it out and put it in the heat preservation The cotton was slowly cooled, and the surface crystallization was observed by naked eyes after cooling. No obvious crystallization was recorded as "A", and obvious crystallization was recorded as "B".

After testing, the fluorophosphate optical glass provided by the present invention has the following properties:

Refractive index (nd) is 1.42-1.45, preferably 1.43-1.44; Abbe number (vd) is 93-96, preferably 94-95.5; Density (ρ) is 3.55 g/cm ³ or less, preferably 3.53 g/cm ³ or less; bubble of class B or more, preferably above A, more preferably A level _0; coefficient of thermal expansion (α _{20 ℃ -120 ℃)} of 160 × 10 ^-7 / K or less, preferably 155 × 10 ^{- Below 7} /K.

The melting and molding methods for producing optical glass can use techniques known to those skilled in the art. The glass raw materials (carbonate, nitrate, metaphosphate, fluoride, oxide, etc.) are weighed and mixed according to the ratio of each ion of the glass and mixed uniformly, and then put into the melting device (such as platinum crucible), and then heated at 900～ After adopting proper stirring, clarification and homogenization at 1250℃, the temperature is lowered to below 900℃, poured or leaked into the forming mold, and finally subjected to post-treatments such as annealing and processing, or directly pressed into shape by precision pressing technology.

The fluorophosphate optical glass of the present invention can be used as a glass preform material for pressure forming, or the molten glass can be directly pressure-formed. The manufacturing method and thermoforming method used as a glass preform material are not specifically limited, A well-known manufacturing method and molding method can be used.

The present invention also provides an optical element, which is formed from the above-mentioned optical glass according to a method well known to those skilled in the art, such as directly performing pressure processing on the molten and softened optical glass to manufacture the optical element. Or, the glass preform material made of the optical glass of the present invention is subjected to pressure processing to manufacture an optical element.

The present invention also provides an optical instrument, which is manufactured by using the above-mentioned manufactured optical element. For example, various lenses such as biconvex, biconcave, plano-convex, plano-concave, and concave-convex lenses, mirrors, ridges, diffraction gratings, etc., can be applied to digital cameras, digital cameras, camera phones and other equipment.

The composition and performance of the fluorophosphate optical glass of the present invention will be described in detail below with reference to specific examples, but the present invention is not limited to the following examples.

[Optical Glass Example]

The composition and refractive index (nd), Abbe number (vd), density (ρ), bubble degree, thermal expansion coefficient (α _{20 ℃ -120) of the fluorophosphate optical glass of the embodiment 1-37 of the present invention and the comparative example 1-3 fluorophosphate optical glass ℃} ), water resistance stability (D _W ) and the results of anti-crystallization performance are shown in Table 1-4 together. The components of each component are expressed in mol%.

Table 1

Table 2

table 3

Table 4

[Examples of optical preforms]

The optical glass obtained in Example 1-37 was cut into a predetermined size, and then a release agent was uniformly coated on the surface, and then it was heated, softened, and pressure-molded to produce a concave meniscus lens and a convex meniscus. Lenses, bi-convex lenses, bi-concave lenses, plano-convex lenses, plano-concave lenses and other lenses, prefabricated parts. Alternatively, the optical glass obtained in Examples 1-37 was used to form a preform for precision press molding, and then the preform was processed by precision press molding into the shape of a lens and a prism.

[Embodiments of Optical Elements]

Annealing the preforms obtained in the above embodiments of the optical preforms, while reducing the internal deformation of the glass, is fine-tuned so that the optical properties such as refractive index can reach the required values.

Next, each preform is ground and polished to produce various lenses, such as concave meniscus lenses, convex meniscus lenses, biconvex lenses, biconcave lenses, plano-convex lenses, and plano-concave lenses. The surface of the obtained optical element may also be coated with an anti-reflection film.

[Optical instrument embodiment]

The optical element prepared by the above-mentioned optical element embodiment is optically designed to form an optical component or optical assembly by using one or more optical elements, which can be used in, for example, imaging equipment, sensors, microscopes, medical technology, digital projection, communications, and optical communications. Technology/information transmission, optics/illumination in the automotive field, photolithography, excimer lasers, chips, computer chips, and integrated circuits and electronic devices including such circuits and chips.

The above descriptions are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modification, equivalent replacement and improvement made within the spirit and principle of the present invention shall be included in the protection of the present invention. Within range.

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Claims (23)

A fluorophosphate optical glass, characterized in that the cation contains P ⁵⁺ , Al ³⁺ and alkaline earth metal ions, and the anion contains F ^- and O ^2- ; the thermal expansion coefficient (α _20°C-120°C ) of the optical glass is 160×10 ^-7 /K or less; density (ρ) is 3.55g/cm ³ or less; water resistance stability (D _w ) is above class 2; Ba ²⁺ /(Ca ²⁺ +Mg ²⁺ ) is 0.08- 0.13. The fluorophosphate optical glass described in item 1 of the scope of patent application is characterized in that it contains P ⁵⁺ : 2-20%, and/or Al ³⁺ : 20-40%, and/or Ba ²⁺ : 0.5-10%, and/or Sr ²⁺ : 5-25%, and/or Ca ²⁺ : 15-35%, and/or Mg ²⁺ : 1-15%; calculated as anion mole percentage , Containing F ^- : 83-95%, and/or O ^2- : 5-17%. A fluorophosphate optical glass, characterized in that it contains P ⁵⁺ : 2-20%, and Al ³⁺ : 20-40%, and Ba ²⁺ : 0.5-10%, and Sr ^{2+ in terms of cation mole percentage} : 5-25%, and Ca ^2+: 15-35%, and Mg ^2+: 1-15%; anion mole percent, containing F ^-: 83-95%, and O ^2-: 5-17% ; Ba ²⁺ /(Ca ²⁺ +Mg ²⁺ ) is 0.08-0.13. The fluorophosphate optical glass according to any one of items 1 to 3 in the scope of the patent application is characterized in that it also contains Ln ³⁺ : 0-6%, and/or Na ⁺ : 0-10%, and/ Or Li ⁺ : 0-10%, and/or K ⁺ : 0-10%, where Ln ³⁺ is one or more of La ³⁺ , Gd ³⁺ , Y ³⁺ and Yb ^3+. A fluorophosphate optical glass, characterized in that it is composed of P ⁵⁺ : 2-20%, and Al ³⁺ : 20-40%, and Ba ²⁺ : 0.5-10%, and Sr ^{2+ in terms of cation mole percentage.} : 5-25%, and Ca ²⁺ : 15-35%, and Mg ²⁺ : 1-15%, and Na ⁺ : 0-10%, and Li ⁺ : 0-10%, and K ⁺ : 0- 10%, and Ln ³⁺ : 0-6%, Ln ³⁺ is one or more of La ³⁺ , Gd ³⁺ , Y ³⁺ and Yb ³⁺ , calculated as anion mole percentage, by F ^- : 83-95%, and O ^2- : 5-17% composition; Ba ²⁺ /(Ca ²⁺ +Mg ²⁺ ) is 0.08-0.13. Such as the fluorophosphate optical glass described in any one or 5 of the scope of the patent application, It is characterized in that the refractive index (nd) of the glass is 1.42-1.45; the Abbe number (vd) is 93-96. The fluorophosphate optical glass described in any one or 5 of the scope of the patent application is characterized in that: P ⁵⁺ : 3-15%, and/or Al ³⁺ : 25-38% , And/or Ba ²⁺ : 1-8%, and/or Sr ²⁺ : 10-22%, and/or Ca ²⁺ : 20-33%, and/or Mg ²⁺ : 2-12%, and /Or Ln ³⁺ : 0-5%, and/or Na ⁺ : 0-4%, and/or Li ⁺ : 0.5-5%, and/or K ⁺ : 0-5%. The fluorophosphate optical glass described in any one or 5 of the scope of the patent application is characterized in that: Ba ²⁺ /Ca ²⁺ is 0.03-0.155, and/or O ^2- /F ^- is 0.105-0.2. The fluorophosphate optical glass described in any one or 5 of the scope of the patent application is characterized in that: P ⁵⁺ : 5-10%, and/or Al ³⁺ : 30-35% , And/or Ba ²⁺ : 1-5%, and/or Sr ²⁺ : 15-20%, and/or Ca ²⁺ : 25-30%, and/or Mg ²⁺ : 5-10%, and /Or Ln ³⁺ : 0.5-3%, and/or Na ⁺ : 0.5-2%, and/or Li ⁺ : 0.5-3%, and/or K ⁺ : 0-2%. The fluorophosphate optical glass described in any one or 5 of the scope of the patent application is characterized in that: Ba ²⁺ /Ca ²⁺ is 0.05-0.155, and/or Ba ²⁺ /( Ca ²⁺ +Mg ²⁺ ) is 0.09-0.125, and/or O ^2- /F ^- is 0.11-0.18. The fluorophosphate optical glass described in any one or 5 of the scope of the patent application is characterized in that: Ba ²⁺ /Ca ²⁺ is 0.1-0.15, and/or Ba ²⁺ /( Ca ²⁺ +Mg ²⁺ ) is 0.1-0.12, and/or O ^2- /F ^- is 0.11-0.15. The fluorophosphate optical glass described in item 4 of the scope of patent application is characterized in that: Y ³⁺ : 0-5%; and/or La ³⁺ : 0-5%; and/or Gd ³⁺ : 0-5%; and/or Yb ³⁺ : 0-5%. The fluorophosphate optical glass described in item 5 of the scope of patent application is characterized in that: Y ³⁺ :0-5%; and/or La ³⁺ :0-5%; and/or Gd ³⁺ :0-5%; and/or Yb ³⁺ :0-5%. The fluorophosphate optical glass described in item 4 of the scope of patent application is characterized in that: Y ³⁺ :0-4%; and/or La ³⁺ :0-3%; and/or Gd ³⁺ :0-3%; and/or Yb ³⁺ :0-3%. The fluorophosphate optical glass described in item 5 of the scope of patent application is characterized in that: Y ³⁺ :0-4%; and/or La ³⁺ :0-3%; and/or Gd ³⁺ :0-3%; and/or Yb ³⁺ :0-3%. The fluorophosphate optical glass described in item 4 of the scope of patent application is characterized in that: Y ³⁺ : 0.5-3%; and/or La ³⁺ : 0-1%; and/or Gd ³⁺ : 0-1%; and/or Yb ³⁺ : 0-1%. The fluorophosphate optical glass described in item 5 of the scope of patent application is characterized in that: Y ³⁺ : 0.5-3%; and/or La ³⁺ : 0-1%; and/or Gd ³⁺ : 0-1%; and/or Yb ³⁺ : 0-1%. The fluorophosphate optical glass described in any one or 5 of the scope of the patent application is characterized in that: the ^{content of F-} is 85-92%; and/or the content of ^{O 2- is 8-15} %. The fluorophosphate optical glass described in any one or 5 of the scope of the patent application is characterized in that: the ^{content of F-} is 87-91%; and/or the content of ^{O 2- is 9-13} %. The fluorophosphate optical glass described in any one or 5 of the scope of patent application is characterized in that the coefficient of thermal expansion (α _20°C-120°C ) of the glass is 155×10 ^-7 /K or less; And/or the density (ρ) is 3.53 g/cm ³ or less; and/or the air bubble degree is above grade A; and/or the water resistance stability (D _W ) is above class 1. An optical preform, characterized in that it is made of the fluorophosphate optical glass described in any one of items 1 to 20 in the scope of patent application. An optical element, characterized in that it is made of the fluorophosphate optical glass described in any one of the 1st to 20th items of the patent application or the optical preform described in the 21st item of the patent application. An optical instrument, characterized in that it is made of the optical element described in item 22 of the scope of patent application.