CN108975683A - Optical glass, the gas preform being prepared by it or optical element and optical instrument - Google Patents

Abstract

The gas preform or optical element and optical instrument being prepared the invention discloses a kind of optical glass, by it.The optical glass is relative to the glass gross mass formed to be converted with oxide, and based on mass percentage, optical glass includes: B₂O₃: 5~25%, Nb₂O₅: 2~15%, SiO₂: 0.5~15%, ZrO₂: 1~15%, TiO₂: 0.5~10% and total amount be 50~75% La₂O₃、Gd₂O₃、Y₂O₃And Yb₂O₃, and be free of Ta₂O₅, La₂O₃With Gd₂O₃Weight ratio La₂O₃/Gd₂O₃It is 1.28~1.625.It applies the technical scheme of the present invention, by the usage ratio between the component, content and specific components of strict control optical glass, so that optical glass of the invention is not using Ta₂O₅In the case where still have excellent performance.

Description

Optical glass, the gas preform being prepared by it or optical element and optics Instrument

Technical field

The present invention relates to optical glass technical fields, in particular to a kind of optical glass, the glass being prepared by it Glass prefabricated component or optical element and optical instrument.

Background technique

Currently, the development of digital photographing apparatus, picture pick-up device and projection device etc., requirement to optical element will be got over Height, this just needs the research and development and production of the optical glass of higher performance.Wherein, what Spectralite with high refractivity and low dispersion was formed is saturating Mirror is combined with the lens formed by high refractivity high dispersion glass, can be corrected color difference, be minimized optical system, Especially refractive index nd is greater than the Spectralite with high refractivity and low dispersion that 1.87, Abbe number vd is greater than 38.0, and the market demand is increasingly Increase.

It is B-La-Zr-Ta relatively good to meet the formula primary structure of above-mentioned photosensitiveness index, is easily conducive to life at glass It produces, but Ta is expensive, is unfavorable for the control of production cost.In addition, it is generally the case that needed in high refractive low dispersive glass prescription system More rare earth oxide is introduced to improve glass refraction, but in different formula systems, more introducing lanthanide oxides It will affect into glassy, if content is more, the easy crystallization of glass can be made, crystallization ceiling temperature is higher, and batch production technique is given to manufacture band Carry out difficulty.

Summary of the invention

The present invention is intended to provide a kind of optical glass, the gas preform being prepared by it or optical element and optics instrument Device, to solve, the easy devitrification of high-refraction low-dispersion optical glass for mold existing in the prior art, volume production difficulty be high, technology of higher cost Problem.

To achieve the goals above, according to an aspect of the invention, there is provided a kind of optical glass.The optical glass phase For the glass gross mass formed to be converted with oxide, based on mass percentage, optical glass includes: B₂O₃: 5~25%, Nb₂O₅: 2~15%, SiO₂: 0.5~15%, ZrO₂: 1~15%, TiO₂: 0.5~10% and total amount be 50~75% La₂O₃、Gd₂O₃、Y₂O₃And Yb₂O₃, and be free of Ta₂O₅, La₂O₃With Gd₂O₃Weight ratio La₂O₃/Gd₂O₃It is 1.28~1.625.

Further, optical glass further includes selected from by ZnO, BaO, CaO, SrO, MgO, WO₃、Sb₂O₃、Li₂O、Na₂O and K₂One of group of O composition is a variety of, and content is as follows: ZnO:0~15%, BaO:0~10%；CaO:0~10%；SrO: 0~10%；MgO:0~10%；WO₃: 0~10%；Sb₂O₃: 0~1%, Li₂O、Na₂O and K₂The total amount of O is 0~10%.

Further, relative to the glass gross mass formed to be converted with oxide, based on mass percentage, optics glass Glass is by B₂O₃: 5~25%, Nb₂O₅: 2~15%, SiO₂: 0.5~15%, ZrO₂: 1~15%, TiO₂: 0.5~10%, ZnO:0 ~15%, BaO:0~10%, CaO:0~10%, SrO:0~10%, MgO:0~10%, WO₃: 0~10%, total amount 0 ~10% Li₂O、Na₂O and K₂O, Sb₂O₃: 0~1% and total amount be 50~75% La₂O₃、Gd₂O₃、Y₂O₃And Yb₂O₃ Composition, wherein La₂O₃With Gd₂O₃Weight ratio La₂O₃/Gd₂O₃It is 1.28~1.625.

Further, relative to the glass gross mass formed to be converted with oxide, based on mass percentage, optics glass Glass includes: B₂O₃: 8~22%, Nb₂O₅: 5.6~10%, SiO₂: 3~10%, ZrO₂: 3~12%, TiO₂: 0.5~7%, and/ Or the La that total amount is 55~70%₂O₃、Gd₂O₃、Y₂O₃And Yb₂O₃。

Further, La₂O₃/Gd₂O₃It is 1.3~1.6.

Further, La₂O₃/Gd₂O₃It is 1.4~1.5.

Further, optical glass is free of Y₂O₃And/or WO₃。

Further, Nb₂O₅With SiO₂Weight ratio Nb₂O₅/SiO₂It is 0.75~2.

Further, Nb₂O₅/SiO₂It is 1~1.5.

Further, the crystallization ceiling temperature of optical glass is lower than 1350 DEG C, preferably shorter than 1300 DEG C.

Further, the refractive index nd > 1.87 of optical glass, preferably nd > 1.88；Abbe number vd > 38.0, preferably vd > 39.0.Further, the water-fast effect stability Dw (powder method) of optical glass is preferably 2 grades or more, more excellent at 3 grades or more Select 1

Grade；Acidproof effect stability DA (powder method) is at 3 grades or more, and preferably 2 grades or more, more preferable 1 grade.

Further, the striped of optical glass is C grades or more, preferably B grades or more, A grades more preferable；Bubble degree be A grades with On, preferably A₀Grade or more, more preferable A₀₀Grade.

According to another aspect of the present invention, a kind of gas preform or optical element are provided.The gas preform or light Element is learned to be prepared by any of the above-described kind of optical glass.

In accordance with a further aspect of the present invention, a kind of optical instrument is provided, which includes optical element, optics member Part is any of the above-described kind of optical element.

It applies the technical scheme of the present invention, by between the component, content and specific components of strict control optical glass Usage ratio, so that optical glass of the invention is not using Ta₂O₅In the case where, it can obtain with devitrification and have excellent performance High-refraction low-dispersion optical glass for mold, and optical glass production cost of the invention is low, is easy to volume production.

Specific embodiment

It should be noted that in the absence of conflict, the features in the embodiments and the embodiments of the present application can phase Mutually combination.Below in conjunction with embodiment, the present invention will be described in detail.

In the present specification, in case of no particular description, the content of each ingredient is all with relative to oxide The quality % of the glass gross mass of the composition of conversion is indicated.Wherein, " using oxide convert form " refer to assuming that as The raw material of glass constituent of the invention melting when whole decomposition and inversion be oxide in the case where, with the oxidation of the generation Composition when each ingredient contained in the glass that the gross mass of object is 100 mass % to indicate.

The basic role that each component plays in optical glass is described below, but is not contained between component due to specific The proportion bring of amount acts synergistically or unexpected effect causes improper restriction.

Glass ingredient

B₂O₃For the framework ingredient of glass, has improve melting property of glass fusible, devitrification resistance and reduction glass in the present invention The effect of dispersion.But when its introduction volume is more than 25%, stability, glass can decline, and refractive index declines, when its introduction volume When less than 5%, glass melting is reduced, and the required optical constant of the present invention is not achieved.Therefore, B of the invention₂O₃Content be 5 ~25%, preferably B₂O₃Content is 8~22%.

Nb₂O₅For the ingredient for improving refractive index and dispersion, it may have improve the devitrification resistance of glass and the work of chemical durability With.Work as Nb₂O₅When content is less than 2%, said effect is not achieved；If its content is more than 15%, glass dispersion is improved, coloring Tendency increases, and is unable to reach the optical characteristics of glass of the present invention, while glass devitrification resistance deteriorates.Nb in the present invention₂O₅Content It is 2~15%, preferably Nb₂O₅Content is 5.6~10%.

SiO₂For the ingredient for constituting glass skeleton, has the function of improving devitrification resistance, increases operating temperature range, separately Outside, also have the effects that the chemical stability for improving glass, the thermal stability for improving glass.If its content is more than 15%, glass The fusible reduced performance of glass, and refractive index required for the present invention can not be obtained.SiO in the present invention₂Content be 0.5~ 15%, preferably SiO₂Content is 3~10%.

ZrO₂For the ingredient for improving refractive index and stability.Due to forming glass as intermidate oxide, so also having Improve the effect of devitrification resistance and chemical durability.ZrO₂Content less than 1% when, be unable to reach above-mentioned desired effect, work as ZrO₂ Content when being more than 15%, there are tendency towards devitrifications to become the tendency that strong, vitrifying becomes difficult.ZrO in the present invention₂Content is 1 ~15%, preferably ZrO₂Content is 3~12%.

TiO₂Also have the function of improving glass refraction, and glass network can be participated in and formed, appropriate introduce makes glass It is more stable.If but it is excessive containing sometimes, glass dispersion can dramatically increase, while the transmissivity of the shortwave part of glass visible light region It reduces, the tendency of glass coloration increases.TiO in the present invention₂Content is 0.5~10%, preferably 0.5~7%.

La₂O₃、Gd₂O₃、Y₂O₃And Yb₂O₃Be improve glass refractive index main component, refractive index but not can be improved Dispersion can be significantly increased.A certain amount of above-mentioned rare earth oxide is added in the application can reduce crystallization ceiling temperature, improve glass The devitrification resistance property of glass improves chemical stability, is not likely to produce glass blister in melting process, the effects of, therefore in the present invention High refractive low dispersive glass formula system in La₂O₃、Gd₂O₃、Y₂O₃And Yb₂O₃Total content is not less than 50%, is no more than 75%, to guarantee to realize above-mentioned technical effect, reach goal of the invention；Preferred scope is 55-70%, more preferable 60-67%.

But under normal conditions, more introducing lanthanide oxides also will affect into glassy, if content is more, make glass Easy crystallization, crystallization ceiling temperature is higher, brings difficulty to batch production technique manufacture；Therefore generally there is high refractive low dispersive performance Lanthanide oxide content just can guarantee that glass is not easy crystallization usually below 60%, and in high refractive low dispersive glass of the invention By controlling lanthanide oxide La₂O₃With Gd₂O₃Weight ratio La₂O₃/Gd₂O₃Ingredient and content for 1.28~1.625, can be with When so that the content of lanthanide oxide is below 60% and more than 60%, it still can guarantee that the crystallization ceiling temperature of glass does not rise Height, crystallization ceiling temperature be lower than 1350 DEG C, preferably shorter than 1300 DEG C, more preferably less than 1280 DEG C, can ensure that component at glass Property is more preferable, be not likely to produce glass blister in melting process, and also guarantee good optical property and processability etc., preferably , La₂O₃/Gd₂O₃It is 1.3~1.6；It is furthermore preferred that La₂O₃/Gd₂O₃It is 1.4~1.5.

The refractive index and dispersion of the adjustable glass of ZnO, suitable ZnO can play the stability or melting for improving glass Property, improve the effect of extrusion forming property, but when its too high levels, refractive index is reduced, and requirement of the invention, while glass is not achieved The devitrification resistance of glass reduces, and crystallization ceiling temperature rises.Therefore ZnO content of the invention is 0~15%, preferably 0~10%, more It is preferred that 0~5%.

BaO, CaO, SrO and MgO this kind of alkaline earth oxide can make chemical stability reduction and the crystallization of glass Ceiling temperature rises, but when respectively content is more than 10% for its, glass devitrification resistance is reduced, thus BaO of the invention for 0~ 10%；CaO content is 0~10%；SrO content is 0~10%, content of MgO is 0~10%.

Li₂O、Na₂O and K₂O is the ingredient for inhibiting split-phase, improving stability, glass.When its content is more than 10%, There are the tendencies that chemical stability significant decrease or refractive index reduce, it is preferred that Li₂O、Na₂O and K₂The total amount of O be 0~ 10%.

It is a kind of according to the present invention that typically embodiment there is provided a kind of optical glass.The optical glass is relative to oxygen The glass gross mass of the composition of compound conversion, based on mass percentage, optical glass includes: B₂O₃: 5~25%, Nb₂O₅: 2 ~15%, SiO₂: 0.5~15%, ZrO₂: 1~15%, TiO₂: 0.5~10% and total amount be 50~75% La₂O₃、 Gd₂O₃、Y₂O₃And Yb₂O₃, and be free of Ta₂O₅, La₂O₃With Gd₂O₃Weight ratio La₂O₃/Gd₂O₃It is 1.28~1.625.

It applies the technical scheme of the present invention, by between the component, content and specific components of strict control optical glass Usage ratio, so that optical glass of the invention is not using Ta₂O₅In the case where, with excellent devitrification resistance and optical Can, it is easy to volume production and production cost is low.

A kind of typical embodiment according to the present invention, optical glass further include selected from by ZnO, BaO, CaO, SrO, WO₃、 Sb₂O₃、Li₂O、Na₂O and K₂One of group of O composition is a variety of, and content is as follows: ZnO:0~15%, BaO:0~10%； CaO:0~10%；SrO:0~10%；WO₃: 0~10%；Sb₂O₃: 0~1%, Li₂O、Na₂O and K₂The total amount of O be 0~ 10%.

A kind of typical embodiment according to the present invention is pressed relative to the glass gross mass formed to be converted with oxide Mass percentage meter, optical glass is by B₂O₃: 5~25%, Nb₂O₅: 2~15%, SiO₂: 0.5~15%, ZrO₂: 1~ 15%, TiO₂: 0.5~10%, ZnO:0~15%, BaO:0~10%, CaO:0~10%, SrO:0~10%, MgO:0~ 10%, WO₃: 0~10%, the Li that total amount is 0~10%₂O、Na₂O and K₂O, Sb₂O₃: 0~1% and total amount be 50~ 75% La₂O₃、Gd₂O₃、Y₂O₃And Yb₂O₃Composition, wherein La₂O₃With Gd₂O₃Weight ratio La₂O₃/Gd₂O₃For 1.28~ 1.625.Usage ratio between the component of strict control optical glass, content and specific components, so that optics glass of the invention Glass is not using Ta₂O₅In the case where, there is preferable devitrification resistance and excellent optical property, be easy to volume production and production cost It is low.

Preferably, a kind of typical embodiment according to the present invention, it is total relative to the glass formed to be converted with oxide Quality, based on mass percentage, the optical glass includes: B₂O₃: 8~22%, Nb₂O₅: 5.6~10%, SiO₂: 3~ 10%, ZrO₂: 3~12%, TiO₂: 0.5~7% and total amount be 55~70% La₂O₃、Gd₂O₃、Y₂O₃And Yb₂O₃, and Without Ta₂O₅, La₂O₃With Gd₂O₃Weight ratio La₂O₃/Gd₂O₃It is 1.28~1.625.

In the present invention, Y₂O₃Meltbility, the devitrification resistance of glass can be improved, while can also reduce devitrification of glass ceiling temperature, If but its content is more than a certain amount of, the stability of glass, devitrification resistance decline.WO₃Play the role of improving refractive index, but works as WO₃When content is more than 10%, there are the tendencies that tendency towards devitrification enhancing, vitrifying become difficult, and dispersion improves significantly, and glass The tendency of the decrease in transmission of the short wavelength side of visible light region, coloring increases, therefore the preferred WO of the present invention₃Content be 0~ 10%.A kind of typical embodiment, optical glass are preferably free of Y according to the present invention₂O₃And/or WO₃。

Pass through control Nb in the present invention₂O₅Content and SiO₂Content ratio Nb₂O₅/SiO₂In 0.75~2, not only The meltbility of glass can be made to increase, effectively increase stability, glass, be not likely to produce striped, glass good evenness has simultaneously The effect that glass refraction, devitrification resistance and chemical durability are improved in the case where not making transmitance be deteriorated, especially when it Nb₂O₅/SiO₂When ratio is 1~1.5, effect is especially apparent.

By adding Sb on a small quantity₂O₃、SnO₂、CeO₂The clarifying effect of glass can be improved in component, but works as Sb₂O₃Content is more than When 1%, glass has the tendency that Clarification Performance reduction, simultaneously because its strong oxidation promotes the deterioration of molding die, therefore The preferred Sb of the present invention₂O₃Additive amount be 0~1%, more preferably 0~0.5%.SnO₂Clarifying agent be can also be used as to add, but When its content is more than 1%, then glass can colour, or when heat, soften glass and carry out die forming etc. shape again when, Sn can become the starting point that nucleus generates, and generate the tendency of devitrification.Therefore SnO of the invention₂Content be preferably 0~1%, it is more excellent It is selected as 0~0.5%, is not added further preferably.CeO₂Effect and additive amount ratio and SnO₂Unanimously, content be preferably 0~ 1%, more preferably 0~0.5%, it does not add further preferably.

Under the premise of not influencing the performance of optical glass of the present invention, a certain amount of P can be suitably introduced into₂O₅、Al₂O₃、 Bi₂O₃、GeO₂、Lu₂O₃With the ingredients such as F.

Optical glass of the invention is high-refractivity and low-dispersion glass, lens made of high-refractivity and low-dispersion glass mostly with The case where lens made of high refractive index high-dispersion glass are combined, and are used for chromatic aberration correction, and optical glass is used as lens Under, more raising refractive index then lens more can be thinning, the folding of of the invention optical glass advantageous for the miniaturization of optical device Penetrate rate nd > 1.87, preferably nd > 1.88, Abbe number vd > 38.0, preferably vd > 39.0.

For optical glass device during manufacture and use, polished surface resists the various etching medium effects such as water, acid Ability be known as the chemical stability of optical glass, depend primarily on the chemical constituent of glass, optical glass of the invention Water-fast effect stability Dw (powder method) is at 3 grades or more, and preferably 2 grades or more, more preferable 1 grade；Acidproof effect stability D_A(powder Method) at 3 grades or more, preferably 2 grades or more, more preferable 1 grade；Using the crystallization property of temperature gradient furnace method measurement glass, glass is made The sample of 180*10*10mm, side polishing are put into the furnace with temperature gradient (5 DEG C/cm) that be warming up to 1400 DEG C of heat preservations 4 small When after take out and naturally cool to room temperature, observe devitrification of glass situation under the microscope, the corresponding maximum temperature of crystal occurs in glass The as crystallization ceiling temperature of glass.The crystallization ceiling temperature of glass is lower, then stability is stronger at high temperature for glass, production Processing performance is better.A kind of typical embodiment according to the present invention, it is preferred that the crystallization ceiling temperature of optical glass is lower than 1350 DEG C, preferably shorter than 1300 DEG C, more preferably less than 1280 DEG C.

Striped degree is the schlieren instrument formed with point light source and lens, from the direction for being easiest to see striped, is tried with standard Sample audit by comparison is divided into 4 grades, respectively A, B, C, D grades, and A grades is, in the case where providing testing conditions, A grades are regulation testing conditions Under the striped that is visible by naked eyes, B grades to there is striped that is thin and dispersing under regulation testing conditions, C grade is provide nothing under testing conditions There are slight parallel stripes, D grades are to have rough striped under regulation testing conditions.Since such product does not make in conventional art With valuable oxide such as Ta₂O₅Under conditions of, anti-crystallization ability is poor, produces the product of 20mm or more thickness, is easy to produce crystallization Striped.And think gauge product is the necessary specification for making heavy caliber (being greater than 60mm) eyeglass.And at present due to optical technology Development, needs heavy caliber eyeglass more and more, and then production firm is required to provide the blank product of 20mm thickness or more.

Optical glass bubble quality is measured by test method as defined in GB/T 7962.8-2010.Bubble degree is glass The middle grade for allowing air bubble content, bubble not only will affect the presentation quality of glassware, but will influence glass optical property, Transparency, mechanical strength etc. cause many adverse effects to glass, therefore the bubble degree for controlling glass is extremely important, the present invention By controlling rare earth oxide La₂O₃、Gd₂O₃、Y₂O₃And Yb₂O₃Total content can also further realize glass blister degree at A grades More than, preferably A₀Grade or more, more preferable A₀₀Grade.

According to another aspect of the present invention, a kind of gas preform or optical element are provided.The gas preform or light Element is learned to be prepared by any of the above-described kind of optical glass.Optical precast product of the invention has high-refractivity and low-dispersion characteristic； Optical element of the invention has high-refractivity and low-dispersion characteristic, can provide the various of excellent in optical properties with low cost The optical elements such as mirror, prism.As the example of lens, can enumerate lens face be spherical surface or aspherical recessed meniscus shaped lens, it is convex The various lens such as meniscus shaped lens, biconvex lens, biconcave lens, plano-convex lens, plano-concave lens.This lens with height by reflecting Lens combination made of rate high-dispersion glass, recoverable color difference are suitable as the lens of chromatic aberration correction.In addition, for optics The densification of system is also effective lens.In addition, due to refractive index height, being imaged by combination for prism In optics system, compact, wide-angle optics system can be realized towards required direction by bending optical path.

In accordance with a further aspect of the present invention, a kind of optical instrument is provided, which includes optical element, optics member Part is any of the above-described kind of optical element.Optical instrument of the invention can be digital camera, video camera etc..

Beneficial effects of the present invention are further illustrated below in conjunction with embodiment.

Embodiment

Optical glass embodiment

Glass in order to obtain with composition shown in 1~table of table 6, uses carbonate, nitrate, hydroxide, oxidation Object, boric acid etc. are used as raw material, and raw material corresponding to optical glass element is weighed each raw material in proportion, become after being sufficiently mixed and adjust Raw material is closed, which is put into platinum crucible, is heated to 1200~1450 DEG C, is formed after fusing, stirring, clarification Uniform melten glass, then will be poured into the mold of preheating after the melten glass moderately cooling and keep 2 at 650~700 DEG C Slow cooling is carried out after~4 hours, obtains optical glass.In addition, measuring the characteristic of each glass by method as shown below, and will Measurement result indicates in 1~table of table 6.

(1) crystallization ceiling temperature

Using the crystallization property of temperature gradient furnace method measurement glass, glass is made to the sample of 180*10*10mm, side polishes, It is put into the furnace with temperature gradient (5 DEG C/cm) to take out after being warming up to 1400 DEG C of heat preservations 4 hours and naturally cools to room temperature, aobvious There is the crystallization ceiling temperature that the corresponding maximum temperature of crystal is glass in micro- microscopic observation devitrification of glass situation, glass.

(2) refractive index nd and Abbe number vd

Refractive index and abbe number are tested according to method as defined in GB/T7962.1-2010.

(3) chemical stability

Water-fast effect stability Dw and acidproof effect stability D is tested by the test method of GB/T 17129_A。

(4) striped degree

It is measured by method as defined in MLL-G-174B.

(5) bubble degree

Optical glass bubble quality is measured by test method as defined in GB/T7962.8-2010.

Table 1

Table 2

Component %	Embodiment 8	Embodiment 9	Embodiment 10	Embodiment 11	Embodiment 12	Embodiment 13	Embodiment 14
								B2O3	12	12.4	11.6	12.9	16	16.6	16
Nb2O5	7.4	6.5	6.5	7.3	7.4	6.7	6.7
								SiO2	3.8	4	4	4.5	3.8	5.8	5.9
ZrO2	6	3	2.8	4	6	5.8	5.8
								TiO2	2.8	2.4	2.6	3	2.8	3	3
La2O3	36	25	25.8	27.8	32	33.5	34
								Gd2O3	25.4	15.9	15.9	16.8	25.4	26	26
Y2O3	0	10	10	0	0	0	0
								Yb2O3	0	0	0	8	0	0	0
Ta2O5	0	0	0	0	0	0	0
								ZnO	0	15	15	0	0	0	0
BaO	0	0	0	8	0	0	0
								CaO	2	3.8	3.8	0	2	2.6	2.6
SrO	0	2	2	0	0	0	0
								MgO	0	0	0	0	0	0	0
WO3	0	0	0	0	0	0	0
								Sb2O3	0	0	0	0	0	0	0
Li2O	3.5	0	0	3	3.5	0	0
								Na2O	1.1	0	0	4.7	1.1	0	0
K2O	0	0	0	0	0	0	0
								La2O3/Gd2O3	1.417323	1.572327	1.622642	1.654762	1.259843	1.288462	1.307692
La2O3+Gd2O3+Y2O3+Yb2O3	61.4	50.9	51.7	52.6	57.4	59.5	60
								Nb2O5/SiO2	1.947368	1.625	1.625	1.622222	1.947368	1.155172	1.135593
Li2O+Na2O+K2O	4.6	0	0	7.7	4.6	0	0
								Total amount	100	100	100	100	100	100	100
Crystallization ceiling temperature DEG C	1290	1330	1350	1360	1370	1300	1290
								Refractive indexnd	1.881	1.881	1.881	1.874	1.876	1.883	1.887
Abbe numbervd	38.25	39.25	38.8	38.5	38.7	39.12	39.23
								Water-fast effect stability Dw	2	2	3	3	3	1	1
Acidproof effect stability DA	2	2	3	3	3	1	1
								Striped	B	B	C	C	C	A	A
Bubble degree	A00	A0	A	B	B	A	A00

Table 3

Table 4

Table 5

Table 6

Optical precast product embodiment

The obtained optical glass of embodiment 1 in table 1 is cut into predefined size, then is equably coated with by nitrogen on the surface Change the release agent that boron powder is constituted, is then heated, softens, be press-formed, make recessed meniscus shaped lens, convex falcate The prefabricated component of the various lens such as lens, biconvex lens, biconcave lens, plano-convex lens, plano-concave lens, prism.

Optical element embodiment

By obtained these prefabricated components annealing of above-mentioned optical precast product embodiment, the same of the deformation of inside glass is being reduced When be finely adjusted so that the optical characteristics such as refractive index reach desirable value.

Then, each prefabricated component is ground, ground, make recessed meniscus shaped lens, male bend moon-shaped lens, biconvex lens, The various lens such as biconcave lens, plano-convex lens, plano-concave lens, prism.Antireflection can be also coated on the surface of gained optical element Film.

The foregoing is only a preferred embodiment of the present invention, is not intended to restrict the invention, for the skill of this field For art personnel, the invention may be variously modified and varied.All within the spirits and principles of the present invention, made any to repair Change, equivalent replacement, improvement etc., should all be included in the protection scope of the present invention.

Claims (13)

1. a kind of optical glass, which is characterized in that relative to the glass gross mass formed to be converted with oxide, by quality percentage Content meter, the optical glass include: B₂O₃: 5~25%, Nb₂O₅: 2~15%, SiO₂: 0.5~15%, ZrO₂: 1~15%, TiO₂: 0.5~10% and total amount be 50~75% La₂O₃、Gd₂O₃、Y₂O₃And Yb₂O₃, and be free of Ta₂O₅, La₂O₃With Gd₂O₃Weight ratio La₂O₃/Gd₂O₃It is 1.28~1.625.

2. optical glass according to claim 1, which is characterized in that the optical glass further include selected from by ZnO, BaO, CaO、SrO、MgO、WO₃、Sb₂O₃、Li₂O、Na₂O and K₂One of group of O composition is a variety of, and content is as follows: ZnO:0~ 15%, BaO:0~10%；CaO:0~10%；SrO:0~10%；MgO:0~10%；WO₃: 0~10%；Sb₂O₃: 0~1%, Li₂O、Na₂O and K₂The total amount of O is 0~10%.

3. optical glass according to claim 1, which is characterized in that total relative to the glass formed to be converted with oxide Quality, based on mass percentage, the optical glass is by B₂O₃: 5~25%, Nb₂O₅: 2~15%, SiO₂: 0.5~15%, ZrO₂: 1~15%, TiO₂: 0.5~10%, ZnO:0~15%, BaO:0~10%, CaO:0~10%, SrO:0~10%, MgO:0~10%, WO₃: 0~10%, the Li that total amount is 0~10%₂O、Na₂O and K₂O, Sb₂O₃: 0~1% and total amount For 50~75% La₂O₃、Gd₂O₃、Y₂O₃And Yb₂O₃Composition, wherein La₂O₃With Gd₂O₃Weight ratio La₂O₃/Gd₂O₃It is 1.28 ~1.625.

4. optical glass according to claim 1 or 3, which is characterized in that relative to the glass formed to be converted with oxide Glass gross mass, based on mass percentage, the optical glass includes: B₂O₃: 8~22%, Nb₂O₅: 5.6~10%, SiO₂: 3 ~10%, ZrO₂: 3~12%, TiO₂: 0.5~7% and/or total amount be 55~70% La₂O₃、Gd₂O₃、Y₂O₃With Yb₂O₃。

5. optical glass according to any one of claim 1 to 3, which is characterized in that the La₂O₃/Gd₂O₃For 1.3~ 1.6；Preferably 1.4~1.5.

6. optical glass according to claim 1 or 2, which is characterized in that the optical glass is free of Y₂O₃And/or WO₃。

7. optical glass according to any one of claims 1 to 3, which is characterized in that Nb₂O₅With SiO₂Weight ratio Nb₂O₅/ SiO₂It is 0.75~2, preferably 1~1.5.

8. optical glass according to any one of claim 1 to 3, which is characterized in that on the crystallization of the optical glass It limits temperature and is lower than 1350 DEG C, preferably shorter than 1300 DEG C.

9. optical glass according to any one of claim 1 to 3, which is characterized in that the refractive index of the optical glass Nd > 1.87, preferably nd > 1.88；Abbe number vd > 38.0, preferably vd > 39.0.

10. optical glass according to any one of claim 1 to 3, which is characterized in that the water-fast work of the optical glass With stability Dw at 3 grades or more, preferably 2 grades or more, more preferable 1 grade；Acidproof effect stability D_AAt 3 grades or more, preferably 2 grades with On, more preferable 1 grade.

11. optical glass according to any one of claim 1 to 3, which is characterized in that the striped of the optical glass is C grades or more, preferably B grades or more, it is A grades more preferable；Bubble degree is A grades or more, preferably A₀Grade or more, more preferable A₀₀Grade.

12. a kind of gas preform or optical element, which is characterized in that the optics as described in any one of claims 1 to 11 Glass preparation forms.

13. a kind of optical instrument, including optical element, which is characterized in that the optical element is as claimed in claim 12 Optical element.