CN104271522B

CN104271522B - Optical glass, preform for precise press molding and optical element and manufacture method thereof

Info

Publication number: CN104271522B
Application number: CN201380020808.XA
Authority: CN
Inventors: 根岸智明; 藤原康裕
Original assignee: Hoya Corp
Current assignee: Hoya Corp
Priority date: 2012-04-26
Filing date: 2013-04-24
Publication date: 2016-11-30
Anticipated expiration: 2033-04-24

Abstract

The optical glass of one mode of the present invention is oxide glass, represents by cation %, comprises: add up to the B of 5～60%³⁺And Si⁴⁺(wherein, B³⁺It is 5～50%), add up to the Zn of more than 5%²⁺And Mg²⁺, add up to the La of 10～50%³⁺、Gd³⁺、Y³⁺And Yb³⁺, and add up to the Ti of 6～45%⁴⁺、Nb⁵⁺、Ta⁵⁺、W⁶⁺And Bi³⁺(wherein, Ti⁴⁺And Ta⁵⁺Total content more than 0%, and W⁶⁺Content more than 5%), cation ratio (Si⁴⁺/B³⁺) it is less than 0.70, cation ratio (Ta⁵⁺/(Ti⁴⁺+Ta⁵⁺)) it is more than 0.23, cation ratio (W⁶⁺/(Nb⁵⁺+W⁶⁺)) it is more than 0.30, cation ratio ((Ti⁴⁺+Nb⁵⁺+Ta⁵⁺+W⁶⁺+Bi³⁺)/(B³⁺+Si⁴⁺)) for more than 0.37 and less than 3.00, cation ratio ((Zn²⁺+Mg²⁺+Li⁺)/(La³⁺+Gd³⁺+Y³⁺+Yb³⁺)) it is more than 0.40, refractive index nd is 1.90～2.00, and meets formula: 25≤ν d < (3.91 nd)/0.06.

Description

Optical glass, preform for precise press molding and optical element and manufacture method thereof

Related application cross-referenced

This application claims that Japanese patent application laid filed in 26 days April in 2012 is willing to the priority of No. 2012-100544, Here quote it particularly as disclosure all to record.

Technical field

The present invention relates to a kind of optical glass with high index of refraction high dispersion characteristics, the essence being made up of above-mentioned optical glass Close press-molding preform, optical element and the manufacture method of described optical element.

Background technology

Known patent document 1 discloses a kind of glass, and it is for making non-spherical lens etc. by precise press molding The optical glass of glass optical element, has B₂O₃-La₂O₃Composition system.Although glass disclosed in patent documentation 1 is rolled at height Penetrating in rate glass is also the low high-refractivity and low-dispersion glass of dispersion, but according to the purposes of optical element, needs ratio here Its document 1 (WO2009/144947A1) all recorded or English US2010/ of the same clan is quoted particularly as open Glass described in 255979A1, U.S. Patent No. No. US8338320 and US2013/079213A1 illustrates high dispersion characteristics Glass of high refractive index.Example as such glass, it is known that here quote its document 2 all recorded particularly as open (JP 2005-247613 publication) or English US2008/167172A1 of the same clan, U.S. Patent No. 7622409, US2010/035744A1, U.S. Patent No. No. 7932197 and US2005/197243A1, document 3 (JP 2011-93781 Number publication) or English US2011/105294A1 of the same clan, document 4 (JP 2011-225384 public affairs) or English of the same clan US2011/257001A1, document 5 (JP 2011-225383 publication) or English US2011/257002A1 of the same clan, document 6 (JP 2010-30879 publication, US2009/325779A1) or English U.S. Patent No. of the same clan 8110514, US2012/ Glass disclosed in 100981A1 and U.S. Patent No. 8410008.

Glass described in patent documentation 2,4～6 is the glass that can carry out precise press molding.But these glass are such as Fruit uses same compression forming mould to carry out accurate compacting for the most hundreds of times, then the surface that there is the glass molded article obtained occurs not Transparent, or the situation that glass melts with mould.Therefore, press formability is improved in order to produce expectation in a large number.This be regarded as due to Along with the high dispersion of glass, the reason that the ratio of high index of refraction height dispersion chemical conversion point increases.

It addition, the glass that document 3 is recorded is when making compressing glass material, has and separate out crystallization at glass surface Situation.Thus, for a large amount of productions of glass material, it is desirable to improve the heat stability of glass further.

Like this, in order to improve the adaptability to precise press molding, also require that heat stability when improving glass manufacture.

One mode of the present invention provides a kind of thermally-stabilised when having good press formability and a glass manufacture Property the excellent optical glass with high index of refraction high dispersion characteristics, and the precise press molding use made by above-mentioned glass Prefabricated component and optical element.

Summary of the invention

One mode of the present invention relates to a kind of optical glass, and it is oxide glass, represents by cation %, comprises:

Add up to the B of 5～60%³⁺And Si⁴⁺(wherein, B³⁺It is 5～50%),

Add up to the Zn of more than 5%²⁺And Mg²⁺,

Add up to the La of 10～50%³⁺、Gd³⁺、Y³⁺And Yb³⁺, and

Add up to the Ti of 6～45%⁴⁺、Nb⁵⁺、Ta⁵⁺、W⁶⁺And Bi³⁺(wherein, Ti⁴⁺And Ta⁵⁺Total content more than 0%, And W⁶⁺Content more than 5%),

Si⁴⁺Content relative to B³⁺The cation ratio (Si of content⁴⁺/B³⁺) it is less than 0.70,

Ta⁵⁺Content relative to Ti⁴⁺And Ta⁵⁺Add up to content cation ratio (Ta⁵⁺/(Ti⁴⁺+Ta⁵⁺)) be 0.23 with On,

W⁶⁺Content relative to Nb⁵⁺And W⁶⁺Add up to content cation ratio (W⁶⁺/(Nb⁵⁺+W⁶⁺)) it is more than 0.30,

Ti⁴⁺、Nb⁵⁺、Ta⁵⁺、W⁶⁺And Bi³⁺Total content relative to B³⁺And Si⁴⁺Add up to content cation ratio ((Ti⁴ ⁺+Nb⁵⁺+Ta⁵⁺+W⁶⁺+Bi³⁺)/(B³⁺+Si⁴⁺)) for more than 0.37 and less than 3.00,

Zn²⁺、Mg²⁺And Li⁺Total content relative to La³⁺、Gd³⁺、Y³⁺And Yb³⁺Add up to content cation ratio ((Zn² ⁺+Mg²⁺+Li⁺)/(La³⁺+Gd³⁺+Y³⁺+Yb³⁺)) it is more than 0.40,

Refractive index nd is the scope of 1.90～2.00, and Abbe number ν d meets following formula (1):

25≤νd<(3.91-nd)/0.06···(1)。

In a mode, the glass transition temperature of above-mentioned optical glass is less than 650 DEG C.

In a mode, the content of the Ge of above-mentioned optical glass presses the GeO in the glass composition of oxide benchmark₂Amount For less than 5.0 mass %, and Te⁴⁺Content relative to Zn²⁺And Mg²⁺Add up to content cation ratio (Te⁴⁺/(Zn²⁺+Mg² ⁺)) it is less than 1.

In a mode, above-mentioned optical glass adds up to the Zn comprising more than 8 cationes %²⁺And Mg²⁺。

In a mode, the content of the Yb of above-mentioned optical glass presses the Yb in the glass composition of oxide benchmark₂O₃Amount For less than 2.0 mass %.

Another mode of the present invention relates to a kind of optical glass, and it is oxide glass, represents by cation %, bag Contain:

Add up to the B of 5～60%³⁺And Si⁴⁺(wherein, B³⁺It is 5～50%),

5～the Zn of 40%²⁺,

Add up to the La of 10～50%³⁺、Gd³⁺、Y³⁺And Yb³⁺,

Add up to the Ti of 5～45%⁴⁺、Nb⁵⁺、Ta⁵⁺、W⁶⁺And Bi³⁺(wherein, Ti⁴⁺And Ta⁵⁺Total content more than 0%, And Nb⁵⁺And W⁶⁺Total content more than 0%),

Refractive index nd is 1.90～2.00, and Abbe number ν d meets above-mentioned formula (1).

Another mode of the present invention relates to the preform for precise press molding being made up of the optical glass of aforesaid way.

Another mode of the present invention relates to the optical element being made up of the optical glass of aforesaid way.

Another mode of the present invention relates to the manufacture method of a kind of optical element, comprises: by heating aforesaid way Preform for precise press molding, uses compression forming mould to carry out precise press molding and obtain the step of optical element.

In a mode, the manufacture method of above-mentioned optical element comprises: imported by preform for precise press molding The step after compression forming mould, it heated together with this finishing die.

In a mode, the manufacture method of above-mentioned optical element comprises: by above-mentioned preform for precise press molding It is conducted into compression forming mould after heating, carries out the step of above-mentioned precise press molding.

A mode according to the present invention, it is provided that be suitable for precise press molding has high index of refraction height dispersion spy Optical glass, the preform for precise press molding being made up of this optical glass and the optical element of property.

Detailed description of the invention

[optical glass]

The optical glass of one mode of the present invention is oxide glass, represents by cation %, comprises:

Add up to the B of 5～60%³⁺And Si⁴⁺(wherein, B³⁺It is 5～50%),

Add up to the Zn of more than 5%²⁺And Mg²⁺,

Add up to the La of 10～50%³⁺、Gd³⁺、Y³⁺And Yb³⁺, and

Refractive index nd is 1.90～2.00, and Abbe number ν d meets following formula (1):

25≤νd<(3.91-nd)/0.06···(1)。

The optical glass of one mode of the present invention is oxide glass, and Main Anions composition is O^2-.As anion Composition, it is also possible to a small amount of interpolation is as the Cl of clarifier^-And F^-, but be to provide for having desired optical characteristics, possess outstanding The optical glass of stability, glass, preferably make O^2-Content be more than 98 aniones %, more than more preferably 99 aniones %, More preferably more than 99.5 aniones %, most preferably 100 aniones %.In a mode of the present invention, cloudy from Sub-% means the percentage rate of anion component.

Hereinafter, the composition for the optical glass of a mode of the present invention illustrates, in more detail as long as no spy Not recording, the content of each cation constituent, total content cation % represent.In one mode of the present invention, cation % Mean the percentage rate of cation constituent.

Glass forms

B³⁺And Si⁴⁺It is the network forming component of glass, there is the effect maintaining stability, glass.At B³⁺And Si⁴⁺Total Content less than 5% in the case of devitrification resistance deteriorate, condensing temperature rise, the manufacture of glass become difficulty.On the other hand, if B³⁺And Si⁴⁺Total content more than 60%, then be difficult to obtain desired refractive index.Therefore, by B³⁺And Si⁴⁺Total content set It is 5～60%.B³⁺And Si⁴⁺Add up to content preferred lower limit be 10%, preferred lower limit is 15%, further preferred Lower limit is 20%, and further preferably lower limit is 25%, and further preferably lower limit is 30%, more preferred Lower limit is 33%.B³⁺And Si⁴⁺Add up to content the preferred upper limit be 50%, the preferred upper limit is 45%, further preferably The upper limit be 43%, further the preferably upper limit is 43%, and the further preferably upper limit is 42%, more preferred The upper limit be 41%.

Wherein, B³⁺Still there is outside the effect above the neccessary composition of the effect of the meltbility maintaining glass.At B³⁺'s Content less than 5% in the case of be difficult to obtain the effect above, if B³⁺Content be difficult to obtain desired refraction more than 50% Rate, and produce striped due to the volatilization of melten glass, optics homogeneity deteriorates.Therefore, by B³⁺Content be set to 5～ 50%.B³⁺The preferred lower limit of content be 10%, preferred lower limit is 15%, and further preferred lower limit is 20%, then enters The one preferred lower limit of step is 25%, and further preferably lower limit is 26%；B³⁺The preferred upper limit of content be 45%, more excellent The upper limit of choosing is 40%, and the further preferred upper limit is 39%, and further the preferably upper limit is 38%, the most preferably The upper limit is 37%.

In the optical glass of a mode of the present invention, from improving the heat stability of glass, realizing being suitable for melted glass Viscosity, the viewpoints such as chemical durability that excessively rise and improve of suppression glass transition temperature that glass shapes are set out, by Si⁴⁺Contain Amount is relative to B³⁺Cation ratio (the Si of content⁴⁺/B³⁺) it is set to less than 0.70.Be preferably less than 0.50, more preferably 0.40 with Under, more preferably less than 0.30, much further preferably from less than 0.20.In order to suppress the rising of liquidus temperature, maintenance Meltbility, devitrification resistance, preferably by cation ratio (Si⁴⁺/B³⁺) it is set to more than 0.01, more preferably it is set to more than 0.02, further It is preferably set to more than 0.03.

Zn²⁺And Mg²⁺Play the meltbility improving glass, make the effect that glass transition temperature reduces.Particularly Zn²⁺Send out Wave and maintaining the effect making glass transition temperature be greatly reduced while high index of refraction, play the stability of optimization glass, make The effect that liquidus temperature reduces.In the optical glass of a mode of the present invention, from the viewpoint of obtaining the effect above, By Zn²⁺And Mg²⁺Total content be set to more than 5%.In order to improve meltbility, make glass transition temperature reduce, preferably by Zn² ⁺And Mg²⁺Total content be set to more than 8%, be more preferably set to more than 9%, be further preferably set to more than 10%, further It is preferably set to more than 12%, is further preferably set to more than 14%, is more further preferably set to more than 16%.

On the other hand, if Zn²⁺And Mg²⁺Total content more than 40%, then illustrate glass stability reduce incline To.It is therefore preferable that Zn²⁺And Mg²⁺Total content be less than 40%.In order to maintain the stability of glass, more preferably Zn well² ⁺And Mg²⁺Total content be less than 35%, more preferably less than 30%, much further preferably from less than 28%, more enter one Step is preferably less than 26%, is more further preferably less than 24%.

And then, in order to make glass transition temperature, liquidus temperature reduce while maintaining high index of refraction, Zn²⁺Contain Measuring preferred lower limit is 5%, and preferred lower limit is 8%, and further preferred lower limit is 9%, further preferred lower limit Being 10%, further preferably lower limit is 12%, more further preferably lower limit is 14%, and then the most preferred Lower limit be 16%.

In order to maintain the stability of glass, Zn well²⁺The preferred upper limit of content be 40%, the preferred upper limit is 35%, the further preferred upper limit is 30%, and further the preferably upper limit is 28%, and the further preferably upper limit is 26%, the more further preferably upper limit is 24%.

Mg²⁺And Zn²⁺Relatively, the effect making glass transition temperature reduce is weak, has the tendency making refractive index reduce.Therefore, Mg²⁺Content be preferably the scope of 0～30%, more preferably 0～the scope of 25%, more preferably 0～the scope of 20%, Much further preferably from 0～the scope of 15%, the most preferably 0～the scope of 10%, be more further preferably 0～ The scope of 5%, and then the most further it is preferably 0～the scope of 1%.Mg²⁺Content can also be 0.

It addition, in order to make glass transition temperature reduce while maintaining the stability of high index of refraction, glass, Zn²⁺'s Content is relative to Zn²⁺And Mg²⁺Add up to content cation ratio (Zn²⁺/(Zn²⁺+Mg²⁺)) it is preferably more than 0.6, more preferably More than 0.8, more preferably more than 0.9, much further preferably from more than 0.95, the most preferably more than 1.0.

La³⁺、Gd³⁺、Y³⁺And Yb³⁺Performance does not improve dispersion, does not the most make relative partial dispersion Δ Pg, and F increases and improves folding Penetrate the effect of rate.At La³⁺、Gd³⁺、Y³⁺And Yb³⁺Total content less than 10% in the case of be difficult to obtain the effect above, if La³⁺、Gd³⁺、Y³⁺And Yb³⁺Add up to content more than 50% glass stability reduce, glass transition temperature rise, glass Meltbility deteriorate.Therefore, by La³⁺、Gd³⁺、Y³⁺And Yb³⁺Total content be set to 10～50%.La³⁺、Gd³⁺、Y³⁺And Yb³⁺ Add up to content preferred lower limit be 12%, preferred lower limit is 14%, and further preferred lower limit is 16%, further Preferably lower limit is 18%；La³⁺、Gd³⁺、Y³⁺And Yb³⁺Add up to content the preferred upper limit be 45%, the preferred upper limit is 40%, the further preferred upper limit is 35%, and further the preferably upper limit is 30%, and the further preferably upper limit is 28%.

La³⁺、Gd³⁺、Y³⁺And Yb³⁺It it is the composition improving glass transition temperature, making meltbility reduce.In contrast, before The Zn recorded²⁺And Mg²⁺Each composition be to make glass transition temperature reduce, improve the composition of meltbility.It addition, optional member Li⁺Also it is the composition making glass transition temperature reduce, improve meltbility.Therefore, in order to make glass transition temperature reduce, change Kind meltbility, in the optical glass of a mode of the present invention, by Zn²⁺、Mg²⁺And Li⁺Total content relative to La³⁺、Gd³ ⁺、Y³⁺And Yb³⁺Add up to content cation ratio ((Zn²⁺+Mg²⁺+Li⁺)/(La³⁺+Gd³⁺+Y³⁺+Yb³⁺)) it is set to more than 0.40. If cation ratio ((Zn²⁺+Mg²⁺+Li⁺)/(La³⁺+Gd³⁺+Y³⁺+Yb³⁺)) less than 0.40, then glass transition temperature rises.Separately Outward, meltbility reduces the melted residual resulting in raw material, when making the melt temperature of glass in order to avoid producing melted residual During rising, as platinum crucible, metal melt container is melted glass attack, as the metal generation ion of container material Change and dissolve in melten glass, glass complexion changed strong.From the above point of view, cation ratio ((Zn²⁺+Mg²⁺+Li⁺)/(La³⁺ +Gd³⁺+Y³⁺+Yb³⁺)) preferred scope be more than 0.50, more preferably scope is more than 0.60, and further preferred scope is 0.70 Above.On the other hand, in order to maintain high index of refraction, cation ratio ((Zn²⁺+Mg²⁺+Li⁺)/(La³⁺+Gd³⁺+Y³⁺+Yb³⁺)) preferably It is less than 2.50, more preferably less than 2.00, more preferably less than 1.50.

Ti⁴⁺、Nb⁵⁺、Ta⁵⁺、W⁶⁺And Bi³⁺It it is the composition playing the effect improving refractive index.At Ti⁴⁺、Nb⁵⁺、Ta⁵⁺、W⁶⁺And Bi³⁺Total content less than 6% in the case of be difficult to obtain desired refractive index.If Ti⁴⁺、Nb⁵⁺、Ta⁵⁺、W⁶⁺And Bi³⁺'s Add up to content more than 45%, then devitrification resistance deteriorates, and precise press molding also deteriorates, relative partial dispersion Pg described later, F's Deviation delta Pg, F increases, and chromatic aberration correction reduces.Therefore, in the optical glass of one mode of the present invention, by Ti⁴⁺、Nb⁵⁺、 Ta⁵⁺、W⁶⁺And Bi³⁺Total content be set to 6～45%.Ti⁴⁺、Nb⁵⁺、Ta⁵⁺、W⁶⁺And Bi³⁺Add up to content preferred lower limit be 8%, preferred lower limit is 10%, and further preferred lower limit is 12%, and further preferably lower limit is 14%, more enters one Walking preferred lower limit is 16%, more further preferably lower limit is 18%, and then the most further preferred lower limit is 20%. Ti⁴⁺、Nb⁵⁺、Ta⁵⁺、W⁶⁺And Bi³⁺The preferred upper limit of total content be 40%, the preferred upper limit is 35%, further preferably The upper limit be 30%.

, melten glass the press-molding preform being made up of glass of high refractive index (is also referred to as being pressed into Shape glass material) when forming, it is possible to glass surface devitrification.It is to give birth to as follows that the devitrification on such surface considers Become.Because melten glass and mold contact, the surface of glass is cooled down rapidly.Owing to the thermal conductivity of glass is little, so while Surface is cooled down rapidly, and inside is still within the condition of high temperature.Afterwards, by the conduction of heat glass surface from inside glass by again Secondary heating.At this moment, separate out crystallization at glass surface and superficial devitrification occurs.The volume of glass is the biggest, and the heat of inside glass is more Greatly, the temperature of glass surface the most easily rises by again heating.Therefore, the glass molded article that volume is the biggest is more susceptible to table Face devitrification.

Only by adjusting liquidus temperature, it is difficult to fully suppress the easily degree of generation of such superficial devitrification.About this point, W⁶⁺There is the effect suppressing such superficial devitrification.In the optical glass of a mode of the present invention, from obtaining sufficient table From the viewpoint of the devitrification inhibition of face, by W⁶⁺Content be set to more than 5%.

At the Ti as the composition giving high index of refraction⁴⁺、Nb⁵⁺、Ta⁵⁺、W⁶⁺、Bi³⁺In, although Ti⁴⁺From maintaining glass It is effective ingredient that the aspect that stability, suppression liquidus temperature rise is set out, but is also easily to make precise press molding deteriorate Composition, contains if a large amount of, and dispersion can become too high.

Nb⁵⁺It is favourable composition for maintaining precise press molding, but from maintaining the stability of glass not Certain preferred.

Ta⁵⁺It is to maintain the stability of glass, precise press molding and preferred component, in above-mentioned imparting high index of refraction Composition in play the effect not improving dispersion and improve refractive index.

W⁶⁺It is effective composition from the aspect improving the stability of glass, suppression liquidus temperature rises, but with Nb⁵⁺、Ta⁵⁺Comparing, the effect improving precise press molding is weak.

Bi³⁺Compared with other composition giving high index of refraction, maintain the stability of glass, improve precise press molding Effect the most weak.

The most in the present invention, it is contemplated that the above-mentioned stability to glass, precise press molding, chromatic aberration correction The impact applied, determines to give the distribution of the composition of high index of refraction as follows.

In order to maintain the stability of glass, containing Ti⁴⁺Or Ta⁵⁺At least one, say, that by Ti⁴⁺And Ta⁵⁺Total Content is set to more than 0%.Ti⁴⁺And Ta⁵⁺Add up to content preferred lower limit be 1%, preferred lower limit is 2%, further Preferably lower limit is 3%, and further preferably lower limit is 4%；The preferably upper limit is 23%, and the preferred upper limit is 20%, The further preferred upper limit is 18%, and further the preferably upper limit is 16%, and the further preferably upper limit is 14%, more more The further preferred upper limit is 12%, and then the most preferably upper limit is 10%.

In the optical glass of a mode of the present invention, as mentioned above by W⁶⁺Content be set to more than 5%.Due to Nb⁵⁺ It is optional member, so Nb⁵⁺And W⁶⁺Add up to the lower limit of content for more than 5%, preferably 6%, more preferably 7%, further It is preferably 8%.

On the other hand, in the optical glass of alternate manner, in order to maintain the stability of glass, containing Nb⁵⁺Or W⁶⁺Extremely Few one, i.e. by Nb⁵⁺And W⁶⁺Total content be set to more than 0%.Nb⁵⁺And W⁶⁺Add up to content preferred lower limit be 2%, Preferred lower limit is 4%, and further preferred lower limit is 6%, and further preferably lower limit is 8%.

In two above-mentioned modes, Nb⁵⁺And W⁶⁺Add up to content the preferred upper limit be 40%, the preferred upper limit Being 35%, the further preferred upper limit is 30%, and further the preferably upper limit is 25%, and the further preferably upper limit is 20%.

In order to maintain the stability of glass, the rising of suppression liquidus temperature, improve precise press molding, suppression relatively Partial dispersion Pg, deviation delta Pg of F, the increase of F, by cation ratio (Ta⁵⁺/(Ti⁴⁺+Ta⁵⁺)) it is set to more than 0.23.Cation Than (Ta⁵⁺/(Ti⁴⁺+Ta⁵⁺)) preferred scope be 0.25～1.00, more preferably in the range of 0.30～1.00, further preferably In the range of 0.40～1.00, the most preferably in the range of 0.50～1.00, the most preferably in the range of 0.60～ 1.00。

In order to maintain the stability of glass, the rising of suppression liquidus temperature, by cation ratio (W⁶⁺/(Nb⁵⁺+W⁶⁺)) set It is more than 0.30.Cation ratio (W⁶⁺/(Nb⁵⁺+W⁶⁺)) preferably in the range of 0.35～1.00, more preferably in the range of 0.40 ～1.00, further preferred range is 0.45～1.00, the most preferably in the range of 0.50～1.00.

And then, at cation ratio ((Ti⁴⁺+Nb⁵⁺+Ta⁵⁺+W⁶⁺+Bi³⁺)/(B³⁺+Si⁴⁺)) it is difficulty in the case of less than 0.37 To obtain desired optical characteristics, if it exceeds the stability of 3.00 glass deteriorates, liquidus temperature rises and is difficult to To desired optical characteristics, therefore by cation ratio ((Ti⁴⁺+Nb⁵⁺+Ta⁵⁺+W⁶⁺+Bi³⁺)/(B³⁺+Si⁴⁺)) be set to more than 0.37 And less than 3.00.Cation ratio ((Ti⁴⁺+Nb⁵⁺+Ta⁵⁺+W⁶⁺+Bi³⁺)/(B³⁺+Si⁴⁺)) preferred lower limit be 0.38, more preferably Lower limit be 0.39, further preferred lower limit is 0.40, and further preferably lower limit is 0.41, further preferably under It is limited to 0.42, more further preferably lower limit is 0.43, and then the most further preferred lower limit is 0.45；Cation ratio ((Ti⁴⁺+Nb⁵⁺+Ta⁵⁺+W⁶⁺+Bi³⁺)/(B³⁺+Si⁴⁺)) the preferred upper limit be 2.50, the preferred upper limit is 2.00, further The preferably upper limit is 1.50, and further the preferably upper limit is 1.00, and the further preferably upper limit is 0.90, more further The preferably upper limit is 0.80.Refractive index nd of optical glass of a mode, Abbe number vd about the present invention are carried out afterwards Discuss.

Si⁴⁺It is the network forming component of glass, there is the effect of the stability improving glass.Further, it may have make glass Viscosity rise, improve the effect of formability when glass shaping body being formed by glass melts.But, if Si⁴⁺'s Content reduces more than 10% refractive index, due to the rising of glass transition temperature, has temperature during precise press molding to rise Tendency.Therefore, in order to improve precise press molding while obtaining desired optical characteristics, preferably by Si⁴⁺Content It is set to 0～10%.Si⁴⁺Content more preferably in the range of 0～7%, further preferred range is 0～5%, further Preferably in the range of 0～3%.

La³⁺Being to play not improve dispersion, the most do not make relative partial dispersion Δ Pg, F increases and improves the effect of refractive index Composition.In order to obtain the effect above, preferably by La³⁺Content be set to more than 5%.If La³⁺Content more than 50%, then The tendency that stability reduces, glass transition temperature rises of glass is shown, the most preferably by La³⁺Content be set to 50% with Under.Therefore, La³⁺The preferred scope of content be 5～50%.La³⁺The preferred lower limit of content be 10%, the most excellent The lower limit of choosing is 12%, and further preferably lower limit is 14%, and further preferably lower limit is 15%；La³⁺Content The preferred upper limit is 45%, and the further preferred upper limit is 40%, and further the preferably upper limit is 35%, the most excellent The upper limit of choosing is 30%, the more further preferably upper limit is 25%, and then the most preferably upper limit is 22%.

Gd³⁺Being to play not improve dispersion, the most do not make relative partial dispersion Δ Pg, F increases and improves the effect of refractive index Composition.But, if Gd³⁺Content illustrate more than 15% glass stability reduce, glass transition temperature rise Tendency, the most preferably by Gd³⁺Content be set to 0～15%.Gd³⁺Content more preferably in the range of 0～10%, further Preferably in the range of 0～8%, the most preferably in the range of 0～7%, the most preferably in the range of 0～6%, more more Further preferred range is 0～5%.

Y³⁺Being to play not improve dispersion, the most do not make relative partial dispersion Δ Pg, F increases and improves the effect of refractive index Composition.But, if Y³⁺Content illustrate more than 15% glass stability reduce, glass transition temperature rise incline To, the most preferably by Y³⁺Content be set to 0～15%.Y³⁺Content more preferably in the range of 0～10%, further preferably In the range of 0～7%, the most preferably in the range of 0～5%, the most preferably in the range of 0～3%.

Yb³⁺Being to play not improve dispersion, the most do not make relative partial dispersion Δ Pg, F increases and improves the effect of refractive index Composition.But, if Yb³⁺Content illustrate more than 10% glass stability reduce, glass transition temperature rise Tendency, the most preferably by Yb³⁺Content be set to 0～10%.Yb³⁺Content more preferably in the range of 0～7%, the most excellent Choosing, in the range of 0～5%, the most preferably in the range of 0～3%, the most preferably in the range of 0～2%, is more more entered One step is preferably in the range of 0～1%, and then the most preferably in the range of 0～0.1%, it is also possible to do not contain Yb³⁺。

The content of the Yb in the optical glass of one mode of the present invention presses the Yb of the glass composition of oxide benchmark₂O₃'s Amount, preferably less than 2.0 mass %, below more preferably 1.9 mass %, more preferably less than 1.5 mass %, then enters one Step is preferably below 1.4 mass %, below the most preferably 1.0 mass %, be more further preferably 0.5 mass % with Under.Additionally " the glass composition of oxide benchmark " refers to that frit is all decomposed when melted, as in optical glass Material as oxide existence carries out converting and obtains glass composition.

Ti⁴⁺It is the composition improving refractive index, but if Ti⁴⁺Content more than 8% produce glass stability fall Low, glass the tendency of strong, the precise press molding reduction of complexion changed etc., the most preferably by Ti⁴⁺The scope of content be set to 0～ 8%.Ti⁴⁺The preferred upper limit of content be 7.5%, the further preferred upper limit is 7.0%, further the preferred upper limit Being 6.0%, the further preferably upper limit is 5.0%, the more further preferably upper limit is 4.0%；Ti⁴⁺Content more excellent The lower limit of choosing is 0.5%, and further preferred lower limit is 1.0%, and further preferably lower limit is 1.5%.

Nb⁵⁺It it is the composition improving refractive index.If Nb⁵⁺Content illustrate more than 30% glass stability reduce, liquid The tendency that liquidus temperature rises, the most preferably by Nb⁵⁺Content be set to 0～30%.Nb⁵⁺The preferred lower limit of content be 0.1%, preferred lower limit is 0.5%, and further preferred lower limit is 1.0%；The preferred upper limit is 30%, the most excellent The upper limit of choosing is 25%, and further the preferably upper limit is 20%, and the further preferably upper limit is 15%, more excellent The upper limit of choosing is 10%.

Ta⁵⁺The composition improving refractive index, with as be the Ti of composition improving refractive index⁴⁺、W⁶⁺Compare illustrate lower Dispersivity, but if contain Ta as glass ingredient⁵⁺Δ Pg, F then can not be made to rise and make glass high index of refraction height dispersion Change.If Ta⁵⁺Content illustrate more than 15% glass stability reduce, liquidus temperature rise tendency.It is therefore preferable that By Ta⁵⁺Content be set to less than 15%.Ta⁵⁺The preferred upper limit of content be 13%, the further preferred upper limit is 10%, further the preferably upper limit is 8%.As described above, due to Ta⁵⁺Give high index of refraction composition in be for Maintenance precise press molding and preferred composition, the most more preferably by Ta⁵⁺Content be set to more than 0.1%, the most excellent Choosing is set to 0.5%, is further preferably set to 1.0%, is further preferably set to more than 1.5%.

W⁶⁺It is to play to improve refractive index, the stability improving glass, the composition of effect that makes liquidus temperature reduce.Separately Outward, W as previously mentioned⁶⁺Also the effect of the superficial devitrification of suppression glass is played.In order to obtain such effect, at one of the present invention In the optical glass of mode, by W⁶⁺Content is set to more than 5%.W⁶⁺The preferred lower limit of content be 5.5%, preferred under Being limited to 6%, further preferred lower limit is 7%.It addition, in another mode, W⁶⁺The preferred lower limit of content be 3%, Preferred lower limit is 4%, and further preferred lower limit is 5%, and further preferably lower limit is 6%, the most preferably Lower limit be 7%.

On the other hand, if W⁶⁺Content the tendency that the stability of glass reduces is shown more than 30%, and liquid is shown The tendency that liquidus temperature rises.In addition illustrate glass the strong tendency of complexion changed.It is therefore preferable that by W⁶⁺Content be set to 30% with Under.W⁶⁺The preferred upper limit of content be 25%, the further preferred upper limit is 20%, and further the preferably upper limit is 18%, the further preferably upper limit is 16%, the more further preferably upper limit is 14%.

Bi³⁺Play and improve refractive index and improve the effect of stability, glass, but if its content is more than 10%, show Go out stability, glass reduction, glass coloration, the tendency of precise press molding deterioration, exist and the container as melting glass Platinum carries out reacting the situation that (alloying) makes platinum deteriorate.Therefore, Bi³⁺Content be preferably set to 0～10%.Bi³⁺Content more Preferably in the range of 0～7%, further preferred range is 0～5%, the most preferably in the range of 0～3%, more enters one Walk preferably in the range of 0～1%, more preferably in the range of 0～0.1%, it is also possible to it is 0%.

Zr⁴⁺It it is the composition playing the effect improving refractive index.If Zr⁴⁺Content more than 10%, stabilization is shown Property reduce, liquidus temperature rise tendency.It is therefore preferable that by Zr⁴⁺Content be set to the scope of 0～10%, be more preferably set to 0 ～the scope of 7%, further preferably it is set to the scope of 0～5%, is further preferably set to the scope of 0～3%.

In order to improve precise press molding, preferably by cation ratio ((Nb⁵⁺+Ta⁵⁺)/(Ti⁴⁺+Nb⁵⁺+Ta⁵⁺+W⁶⁺+Bi³ ⁺)) it is set to more than 0.01.It addition, for the stability improving glass, preferably by cation ratio ((Nb⁵⁺+Ta⁵⁺)/(Ti⁴⁺+Nb⁵⁺+ Ta⁵⁺+W⁶⁺+Bi³⁺)) be set to less than 0.7.Cation ratio ((Nb⁵⁺+Ta⁵⁺)/(Ti⁴⁺+Nb⁵⁺+Ta⁵⁺+W⁶⁺+Bi³⁺)) preferred Lower limit is 0.05, and further preferred lower limit is 0.10, and further preferably lower limit is 0.15, further preferably lower limit It is 0.20, more further preferably lower limit is 0.23.

Cation ratio ((Nb⁵⁺+Ta⁵⁺)/(Ti⁴⁺+Nb⁵⁺+Ta⁵⁺+W⁶⁺+Bi³⁺)) the preferred upper limit be 0.68, further The preferably upper limit is 0.66, and further the preferably upper limit is 0.64, and the further preferably upper limit is 0.62, more further The preferably upper limit is 0.60.

If Ti⁴⁺Content relative to Ti⁴⁺、Nb⁵⁺、Ta⁵⁺、W⁶⁺And Bi³⁺Add up to content cation ratio (Ti⁴⁺/(Ti⁴ ⁺+Nb⁵⁺+Ta⁵⁺+W⁶⁺+Bi³⁺)) more than 0.43, then the tendency that precise press molding deteriorates being shown, it is shown that the stability of glass is also The tendency deteriorated, it is shown that the tendency that liquidus temperature rises.Deviation delta Pg of relative partial dispersion Pg in addition, F, F increases, for Chromatic aberration correction is unfavorable.It is therefore preferable that by cation ratio (Ti⁴⁺/(Ti⁴⁺+Nb⁵⁺+Ta⁵⁺+W⁶⁺+Bi³⁺)) it is set to less than 0.43.Sun from Son is than (Ti⁴⁺/(Ti⁴⁺+Nb⁵⁺+Ta⁵⁺+W⁶⁺+Bi³⁺)) more preferably in the range of less than 0.41, further preferred range is Less than 0.39, the most preferably in the range of less than 0.35, the most preferably in the range of less than 0.30, more further Preferably in the range of less than 0.25, and then the most preferably in the range of less than 0.20.

If Ti⁴⁺、Nb⁵⁺、Ta⁵⁺、W⁶⁺And Bi³⁺Total content relative to La³⁺、Gd³⁺、Y³⁺And Yb³⁺Add up to content Cation ratio ((Ti⁴⁺+Nb⁵⁺+Ta⁵⁺+W⁶⁺+Bi³⁺)/(La³⁺+Gd³⁺+Y³⁺+Yb³⁺)) less than 0.40, then the stability of glass is shown The tendency that reduction, liquidus temperature rise.In addition produce and be difficult to obtain the tendency of desired optical characteristics.If cation ratio ((Ti⁴⁺+Nb⁵⁺+Ta⁵⁺+W⁶⁺+Bi³⁺)/(La³⁺+Gd³⁺+Y³⁺+Yb³⁺)) more than 4.00, then stability, glass reduction, liquid phase are shown The tendency that line temperature rises.In addition produce and be difficult to obtain the tendency of desired optical characteristics.

It is therefore preferable that by cation ratio ((Ti⁴⁺+Nb⁵⁺+Ta⁵⁺+W⁶⁺+Bi³⁺)/(La³⁺+Gd³⁺+Y³⁺+Yb³⁺)) it is set to 0.40 ～the scope of 4.00.Cation ratio ((Ti⁴⁺+Nb⁵⁺+Ta⁵⁺+W⁶⁺+Bi³⁺)/(La³⁺+Gd³⁺+Y³⁺+Yb³⁺)) preferred lower limit Being 0.50, further preferred lower limit is 0.55, and further preferably lower limit is 0.60, and further preferably lower limit is 0.65, more further preferably lower limit is 0.70；The preferred upper limit is 3.50, and the further preferred upper limit is 3.00, then The further preferred upper limit is 2.50, and the further preferably upper limit is 2.00, the more further preferably upper limit is 1.50.

Li⁺、Na⁺、K⁺The effect be respectively provided with the effect reducing glass transition temperature, improving the meltbility of glass, but such as Really Li⁺、Na⁺And K⁺Total content more than 10%, then tendency that refractive index reduces is shown and illustrates that the stability of glass reduces Tendency.It is therefore preferable that by Li⁺、Na⁺And K⁺The content that adds up to be set to the scope of 0～10%, be more preferably set to the model of 0～8% Enclose, be further preferably set to the scope of 0～6%, be further preferably set to the scope of 0～4%, be further preferably set to 0 ～the scope of 2%, more further it is preferably set to the scope of 0～1%, and then the most further it is preferably set to the model of 0～0.5% Enclose, be particularly preferably set to the scope of 0～0.1%.Li⁺、Na⁺And K⁺Total content can also be 0%.

Illustrate below for each alkali metal component.

Li⁺Alkali metal component is maintain high index of refraction characteristic and the effect that makes glass transition temperature reduce big Composition.It addition, it also plays the effect improving glass melting.If Li⁺Content more than 10%, then illustrate that refractive index reduces Tendency, and illustrate glass stability reduce tendency.And then, because Li⁺Volatility is shown in the molten state, so When being made glass shaping body by glass melts, sometimes become the reason producing striped from glass surface volatilization.In order to maintain High index of refraction, obtain the glass of optically homogenizing, preferably by Li⁺Content be set to the scope of 0～10%, be more preferably set to 0～ The scope of 7%, is further preferably set to the scope of 0～5%, is further preferably set to the scope of 0～3%, the most excellent Choosing is set to the scope of 0～1%, is more further preferably set to the scope of 0～0.5%, so be the most further preferably set to 0～ The scope of 0.1%.Further, Li⁺Content can also be 0%.

Na⁺It it is the composition with the effect making glass transition temperature reduce.It addition, it also plays improves the melted of glass The effect of property.If Na⁺Content more than 10%, then the tendency that refractive index reduces is shown, and also shows that the stability of glass The tendency reduced.And then, because Na⁺Volatility is shown in the molten state, so being made glass shaping body by glass melts Time, the reason producing striped is sometimes become from glass surface volatilization.In order to maintain high index of refraction, obtain the glass of optically homogenizing Glass, preferably by Na⁺Content be set to the scope of 0～10%, be more preferably set to the scope of 0～7%, be further preferably set to 0～ The scope of 5%, is further preferably set to the scope of 0～3%, is further preferably set to the scope of 0～1%, more more enters one Step is preferably set to the scope of 0～0.5%, and then is the most further preferably set to the scope of 0～0.1%.Further, Na⁺Content Can also be 0%.

K⁺It it is the composition with the effect making glass transition temperature reduce.It addition, it also plays improves the melted of glass The effect of property.If K⁺Content more than 10%, then the tendency that refractive index reduces is shown, and also shows that the stability fall of glass Low tendency.And then, because K⁺Volatility is shown in the molten state, so when being made glass shaping body by glass melts, Sometimes the reason producing striped is become from glass surface volatilization.In order to maintain high index of refraction, obtain the glass of optically homogenizing, Preferably by K⁺Content be set to the scope of 0～10%, be more preferably set to the scope of 0～7%, be further preferably set to 0～5% Scope, is further preferably set to the scope of 0～3%, is further preferably set to the scope of 0～1%, more preferred It is set to the scope of 0～0.5%, and then is the most further preferably set to the scope of 0～0.1%.Further, K⁺Content can also be 0%.

Mg²⁺、Ca²⁺、Sr²⁺、Ba²⁺It is respectively provided with the effect of the meltbility improving glass, but if Mg²⁺、Ca²⁺、Sr²⁺And Ba²⁺Total content more than 10%, then illustrate glass stability reduce, liquidus temperature rise tendency.It is therefore preferable that will Mg²⁺、Ca²⁺、Sr²⁺And Ba²⁺The content that adds up to be set to the scope of 0～10%, be more preferably set to the scope of 0～8%, the most excellent Choosing is set to the scope of 0～6%, is further preferably set to the scope of 0～4%, is further preferably set to the scope of 0～2%, The most further it is preferably set to the scope of 0～1%, and then is the most further preferably set to the scope of 0～0.5%, particularly preferably It is set to the scope of 0～0.1%.Mg²⁺、Ca²⁺、Sr²⁺And Ba²⁺Total content can also be 0%.

Illustrate below for each alkaline-earth metal composition.

Mg²⁺There is the effect of the meltbility improving glass.But, if Mg²⁺Content more than 10%, then glass is shown Stability reduce, liquidus temperature rise tendency.It addition, because refractive index also reduces, it is advantageous to by Mg²⁺Content set It is 0～10%, is more preferably set to the scope of 0～7%, be further preferably set to the scope of 0～5%, be further preferably set to 0 ～the scope of 3%, further it is preferably set to the scope of 0～1%, is more further preferably set to the scope of 0～0.5%, enter And the most further it is preferably set to the scope of 0～0.1%.Further, Mg²⁺Content can also be 0%.

Ca²⁺There is the effect of the meltbility improving glass.But, if Ca²⁺Content more than 10%, then glass is shown Stability reduce, liquidus temperature rise tendency.It addition, because refractive index also reduces, it is advantageous to by Ca²⁺Content set It is 0～10%, is more preferably set to the scope of 0～7%, be further preferably set to the scope of 0～5%, be further preferably set to 0 ～the scope of 3%, further it is preferably set to the scope of 0～1%, is more further preferably set to the scope of 0～0.5%, enter And the most further it is preferably set to the scope of 0～0.1%.Further, Ca²⁺Content can also be 0%.

Sr²⁺There is the effect of the meltbility improving glass.But, if Sr²⁺Content more than 10%, then glass is shown Stability reduce, liquidus temperature rise tendency.The most preferably by Sr²⁺Content be set to 0～10%, be more preferably set to 0 ～the scope of 7%, further preferably it is set to the scope of 0～5%, is further preferably set to the scope of 0～3%, further It is preferably set to the scope of 0～1%, is more further preferably set to the scope of 0～0.5%, and then be the most further preferably set to 0 ～the scope of 0.1%.Further, Sr²⁺Content can also be 0%.

Ba²⁺There is the effect improving glass melting.But, if Ba²⁺Content more than 10%, then glass is shown The tendency that stability reduces, liquidus temperature rises.The most preferably by Ba²⁺Content be set to 0～10%, be more preferably set to 0～ The scope of 7%, is further preferably set to the scope of 0～5%, is further preferably set to the scope of 0～3%, the most excellent Choosing is set to the scope of 0～1%, is more further preferably set to the scope of 0～0.5%, so be the most further preferably set to 0～ The scope of 0.1%.Further, Ba²⁺Content can also be 0%.

Al³⁺It is that performance improves the stability of glass, improves the composition of the effect of chemical durability.But, if Al³⁺'s Content more than 10%, then illustrates that refractive index reduces tendency, and illustrates the tendency that the stability of glass reduces.Therefore Al³⁺Contain Measuring preferred scope is 0～10%, and more preferably in the range of 0～7%, further preferred scope is 0～5%, particularly preferred scope Being 0～3%, particularly preferably scope is 0～1%, and the most particularly preferably scope is 0～0.5%, the most particularly preferably Scope is 0～0.1%.Further, Al³⁺Content can also be 0%.

Te⁴⁺It it is the composition of the effect of performance raising refractive index and the stability improving glass.But, if Te⁴⁺'s Content more than 10%, then illustrates the tendency that stability reduces, liquidus temperature rises of glass.It is therefore preferable that by Te⁴⁺Content It is set to the scope of 0～10%, is more preferably set to the scope of 0～7%, be further preferably set to the scope of 0～5%, further It is preferably set to the scope of 0～3%, is further preferably set to the scope of 0～1%, is more further preferably set to 0～0.5% Scope, and then be the most further preferably set to the scope of 0～0.3%, be particularly preferably set to the scope of 0～0.1%.Te⁴⁺'s Content can also be 0%.Further, from the viewpoint of in view of environmental pressure, preferably further cut down Te⁴⁺Content.

Adding up to the Zn containing more than 5%²⁺And Mg²⁺Glass in, in order to maintain the stability of glass, preferably Te⁴⁺Contain Amount is relative to Zn²⁺And Mg²⁺Add up to content cation ratio (Te⁴⁺/(Zn²⁺+Mg²⁺)) be less than 1.0, more preferably 0.5 with Under, more preferably less than 0.1.It addition, the content of Te presses the TeO in the glass composition of oxide benchmark₂Amount, be preferably Less than 1 mole of %, more preferably 0.5 mole below %, more preferably less than 0.3 mole of %, much further preferably from not 0.1 mole of % of foot.

Ge⁴⁺It it is the composition of the effect of performance raising refractive index and the stability improving glass.But, if Ge⁴⁺'s Content more than 10%, then illustrates the tendency that the stability of glass reduces.The most preferably by Ge⁴⁺Content be set to the model of 0～10% Enclose, be more preferably set to the scope of 0～7%, be further preferably set to the scope of 0～5%, be further preferably set to 0～3% Scope, is further preferably set to the scope of 0～1%, is further preferably set to the scope of 0～0.5%, more excellent Choosing is set to the scope of 0～0.1%.Ge⁴⁺Content can also be 0%.Further, Ge⁴⁺At the material used as glass ingredient In be extremely expensive composition, therefore from suppression manufacturing cost increase from the viewpoint of, preferably reduce its usage amount.

About the content of Ge, for the GeO in forming by the glass of oxide benchmark₂The preferred scope of amount illustrates.

In order to maintain the stability of glass, suppression manufacturing cost to increase, the content of Ge presses the glass composition of oxide benchmark In GeO₂Amount is preferably less than 5.0 mass %, more preferably less than 4 mass %, more preferably less than 3 mass %, then More preferably less than 2 mass %, the most preferably less than 1 mass %, more further be preferably 0.5 mass % with Under, particularly preferably 0 mass %.

The optical glass of one mode of the present invention is oxide glass, and Main Anions composition is O as previously mentioned^2-.Make For except O^2-Anion component in addition, it is also possible to introduce F on a small quantity^-、Cl^-Deng halogenic ingredient.But, paying attention to suppression melten glass Volatility, make shaping be easier to make in the case of, preferably suppression there is volatile F^-The introduction volume of composition, say, that Do not introduce F^-Composition.Further, not as glass ingredient, but minimal amount of halogens, example can also be added as clarifier As F, Cl carry out melten glass.

Sb can also be added on a small quantity as clarifier₂O₃, carbonate, sulfate, nitrate etc..But adding Sb₂O₃'s In the case of, owing to the oxidizing force of Sb is strong, so in order to not make it promote the redox reaction of the forming face with compression forming mould, Preferably by Sb₂O₃Additional addition be set to the scope of 0～1 mass %, be more preferably set to the scope of 0～0.5 mass %.

Further, owing to Fe, Cr, Co, Cu make glass coloration, it is advantageous to without.It addition, it is also preferred that do not introduce Pb, Cd, Tl, As etc. may produce dysgenic composition to environment.

Lu, Ga can introduce in the range of the purpose of the present invention on a small quantity not hindering, but owing to these compositions are the most high Expensive, do not use and can reach the purpose of the present invention yet, so in order to suppress cost increase, the most not introducing Lu, Ga.

Optical characteristics

Refractive index nd of the optical glass of one mode of the present invention is 1.90～2.00, Abbe number vd meets following formula (1).

25≤νd<(3.91-nd)/0.06···(1)

It is more than 1.90 by refractive index nd making glass, such that it is able to provide image pickup optical system, projection optics system The multifunction of system, the material of the effective optical element of densification.But, if refractive index nd is more than 2.00, then glass is steady Qualitative, precise press molding deteriorates, and therefore refractive index nd is set to less than 2.00.

If Abbe number vd is less than 25, then relative partial dispersion Pg, deviation delta Pg of F, F increases, it is shown that chromatic aberration correction merit The tendency that can reduce, also shows that the tendency that the stability of glass, precise press molding deteriorate.On the other hand, if Abbe number Vd is more than ((3.91-nd)/0.06), then in the situation by carrying out correcting chromatic aberration with the combination of low dispersion optical element Under, it is impossible to increase is poor with the Abbe number of the Abbe number of low dispersion, the most preferred in terms of chromatic aberration correction.Therefore, Abbe number is made Vd meets (1) formula as above.

In order to provide the multifunction to optical system, densification effective optical glass, preferably to meet following (2) formula Mode determine the lower limit of refractive index, in the way of meeting following (3) formula, more preferably determine the lower limit of refractive index, further In the way of meeting following (4) formula, preferably determine the lower limit of refractive index, the most preferably in the way of meeting following (5) formula Determine the lower limit of refractive index, in the way of meeting following (6) formula, the most preferably determine the lower limit of refractive index, more more enter One step preferably determines the lower limit of refractive index in the way of meeting following (7) formula, and then preferably the most following to meet (8) mode of formula determines the lower limit of refractive index.

nd≥2.214-0.01×νd···(2)

nd≥2.218-0.01×νd···(3)

nd≥2.222-0.01×νd···(4)

nd≥2.226-0.01×νd···(5)

nd≥2.230-0.01×νd···(6)

nd≥2.238-0.01×νd···(7)

nd≥2.246-0.01×νd···(8)

On the other hand, in order to maintain the stability of glass, preferably refractive index nd is set to less than 1.99, is more preferably set to Less than 1.98, further preferably it is set to less than 1.97, is further preferably set to less than 1.96.

In order to maintain the stability of glass, precise press molding, and suppressing Δ Pg, the increase of F, preferably by Abbe number Vd, for setting more than 25.5, is more preferably set to more than 26.0, is further preferably set to more than 27.0, is further preferably set to 27.5 Above.

About the upper limit of Abbe number, preferably determine in the way of meeting following (9) formula according to aforementioned reason, more preferably with full Foot is stated the mode of (10) formula and is determined, further preferably determines in the way of meeting following (11) formula.

νd<(3.90-nd)/0.06···(9)

νd<(3.89-nd)/0.06···(10)

νd<(3.88-nd)/0.06···(11)

The optical glass of one mode of the present invention is owing to having above-mentioned Abbe number vd and also can show which low relative Partial dispersion, is thus suitable for the material as the effective optical element of chromatic aberration correction to high-order.Here, relative partial dispersion Pg, F use g line, F line, each refractive index ng of c line, nF, nc to be expressed as (ng-nF)/(nF-nc).In the present invention, ng, nF, nc are The value asked for by the method shown in embodiment described later.

In relative partial dispersion Pg, F-Abbe number vd figure, when becoming the base reference of reference of normal segments dispersive glass When relative partial dispersion more than line is expressed as Pg, F (0), Pg, F (0) represent with following formula with Abbe number vd.

Pg, F (0)=0.6483-(0.0018 × ν d)

Deviation delta Pg of relative partial dispersion Pg, F, F is the deviation of the relative partial dispersion from said reference line, under using Formula represents.

Δ Pg, F=Pg, F-Pg, F (0)

=Pg, F+ (0.0018 × ν d)-0.6483

In order to improve the chromatic aberration correction of high-order, preferably Δ Pg, F are set to less than 0.0150, are more preferably set to Less than 0.0100, further preferably it is set to less than 0.0080, is further preferably set to less than 0.0060, the most preferably sets It is less than 0.0040, is more further preferably set to less than 0.0020, and then be the most further preferably set to less than 0.0010.

But, if making Δ Pg, F is too small, is difficult to obtain the glass of desired refractive index, Abbe number, and stability, glass is also The tendency of reduction is shown, the most preferably Δ Pg, F is set to more than-0.0060, be more preferably set to more than-0.0055, the most excellent Choosing is set to more than-0.0050, is further preferably set to more than-0.0045, further be preferably set to more than-0.0040, then The most particularly preferably it is set to more than-0.0030.

Transmission characteristics

While the optical glass of one mode of the present invention is glass of high refractive index, it is also possible to cross over the width of visible region Wave-length coverage demonstrates high light transmittance.In the optimal way of the optical glass of a mode of the present invention, λ 70 represents The degree of staining of below 500nm.λ 70 more preferably in the range of below 480nm, further preferred range is below 460nm, then Further preferred range is below 450nm.The preferred lower limit of λ 70 is not particularly limited, but using 350nm as λ 70 times The target of limit considers preferably.Here λ 70 is the wavelength that light transmittance becomes 70% in the range of wavelength 280-700nm. Here, light transmittance is the glass specimen with the face of being parallel to each other using the thickness being polished to 10.0 ± 0.1mm, from relatively The spectral-transmission favtor obtained in the face vertical direction incident illumination of above-mentioned polishing, is i.e. setting the light intensity inciding said sample It is set to Iout/Iin during Iout for the light intensity of Iin, transmission said sample.Spectral-transmission favtor also comprises the light of specimen surface Reflection loss.It addition, above-mentioned polishing means relative to the wavelength measuring wavelength region, surface roughness is smoothed and turns to enough Little state.The optical glass of one mode of the present invention than λ 70 in the visible region of long wavelength side, light transmission Rate is more than 70%.

Identical with λ 70, λ 5 can be defined below.λ 5 is the wavelength that spectral-transmission favtor becomes 5%.λ 5 preferably in the range of Below 400nm, more preferably in the range of below 390nm, further preferred range is below 380nm, the most preferably Scope is below 370nm.The lower limit of λ 5 is not particularly limited, but considers preferably using 300nm as the target of λ 5 lower limit.

Above-mentioned spectral-transmission favtor measures as mentioned above in the range of wavelength 280～700nm, but if generally increases from λ 5 Long wavelength, then light transmittance increase, if reaching λ 70, then until wavelength 700nm keep more than 70% highly transmissive Rate.

Glass transition temperature

While the optical glass of one mode of the present invention is glass of high refractive index, it is also possible to illustrate that low vitrification turns Temperature, is thus suitable for the glass as precise press molding.Preferred side at the optical glass of one mode of the present invention In formula, glass transition temperature is less than 650 DEG C.Glass transition temperature is that the optical glass of less than 650 DEG C can be by precision Glass temperature time compressing maintains ratio within the scope of relatively low temperature, and when can suppress compressing, glass be with compressing The reaction in face, maintains good state by precise press molding.From such a viewpoint, preferably by glass transition temperature Degree is set to less than 640 DEG C, is more preferably set to less than 630 DEG C, is further preferably set to less than 620 DEG C, is further preferably set to Less than 610 DEG C, further it is preferably set to less than 600 DEG C.

If further, make glass transition temperature excessively reduce, then illustrate that the stability of glass reduces, refractive index reduces Tendency, is the most preferably set to glass transition temperature more than 500 DEG C, is more preferably set to more than 520 DEG C, is further preferably set to More than 540 DEG C, further it is preferably set to more than 560 DEG C, is further preferably set to more than 570 DEG C.

Liquidus temperature

The optical glass of one mode of the present invention can demonstrate outstanding heat stability by having above-mentioned composition, In optimal way, the liquidus temperature as heat stability index is less than 1300 DEG C.Low liquidus temperature can be anti- Only suppress the rising of melt temperature while devitrification, it is also possible to suppression glass melts is invaded the melt container of platinum, platinum alloy etc. Erosion, suppression being mixed into of platina matter, platinum ion dissolve in the glass coloration caused.Further, since glass melts can also be suppressed Flow out temperature, it is possible to prevent striped from producing, it is easy to the glass of homogenizing on shaped optical.Liquidus temperature preferred on Being limited to 1250 DEG C, the further preferred upper limit is 1200 DEG C, and further the preferably upper limit is 1150 DEG C, the most preferably The upper limit is 1130 DEG C, the more further preferably upper limit is 1100 DEG C.But, if making liquidus temperature excessively reduce, then show Going out the tendency that refractive index reduces, glass transition temperature rises, therefore liquidus temperature is preferably more than 1000 DEG C, more preferably More than 1020 DEG C, more preferably more than 1030 DEG C.

Proportion

About optical system, while densification, it also is intended to constitute the lightweight of the optical element of optical system.This The optical glass of a bright mode is glass of high refractive index, but can illustrate than relatively low ratio in glass of high refractive index Weight, is therefore favourable for above-mentioned lightweight.In the optimal way of the optical glass of one mode of the present invention, the ratio of glass It is heavily less than 6.5.The preferred upper limit of proportion is 6.3, and the further preferred upper limit is 6.0, further the preferred upper limit Being 5.9, the further preferably upper limit is 5.8, the more further preferably upper limit is 5.7.

But, if making proportion excessively reduce, then the tendency that the stability of glass reduces being shown, refractive index also shows that reduction Tendency, therefore the preferred lower limit of proportion is 4.5, and preferred lower limit is 4.7, and further preferred lower limit is 4.9, then enters The one preferred lower limit of step is 5.0, and further preferably lower limit is 5.1, more further preferably lower limit is 5.2.

Also providing a kind of optical glass as another mode, it is oxide glass, represents by cation %, bag Contain:

Add up to the B of 5～60%³⁺And Si⁴⁺(wherein, B³⁺It is 5～50%),

5～the Zn of 40%²⁺,

Add up to the La of 10～50%³⁺、Gd³⁺、Y³⁺And Yb³⁺,

Refractive index nd is 1.90～2.00, and Abbe number ν d meets above-mentioned formula (1)

25≤νd<(3.91-nd)/0.06···(1)

About detailed content, the record that the optical glass of the mode being referred to the above-mentioned present invention is correlated with.

The manufacture of optical glass

The optical glass of one mode of the present invention is in the way of obtaining the glass composition of target, using the oxidation as raw material Thing, carbonate, sulfate, nitrate, hydroxide etc. weigh, are in harmonious proportion, and are sufficiently carried out being mixed mixing raw material, melted Carry out in container heating, melt, deaeration, stirring, make homogenizing and without alveolate melten glass, by being shaped, can Obtain optical glass.Known fusion method specifically can be used to make.

[preform for precise press molding]

Preform for precise press molding then for a mode of the present invention illustrates.

The preform for precise press molding of one mode of the present invention is by the optics glass of the invention described above mode Glass is constituted.

Preform for precise press molding (hereinafter referred to as prefabricated component) means the glass blocks for precise press molding, is There is the glass shaping body of the quality suitable with the quality of precise press molding product.Hereinafter, it is described in detail about prefabricated component.

Prefabricated component mean to carry out heating and for the glass preform of precise press molding, accurate compacting here Shape and the most also referred to as mold optical forming, be by the transfer of the forming face of compression forming mould is formed optical element The method in optical function face.Further, optical function face means to make the light of control object carry out reflecting, instead in optical element Penetrating, diffraction, enter the face of outgoing, the lens face in lens etc. is equivalent to this optical function face.

In order to prevent the reaction of glass and compression forming mould forming face when precise press molding, melt and make glass edge Forming face to extend well, preferably cover mold release film on the surface of prefabricated component.Your gold is kind as mold release film can enumerate Belong to (platinum, platinum alloy), oxide (oxide etc. of Si, Al, Zr, La, Y), nitride (nitride etc. of B, Si, Al), carbon containing Film.

As containing carbon film be preferably using carbon as main component (when representing the constituent content in film with atom %, carbon Content is more than the content of other elements) film.Specifically, carbon film, Soft Hydrogenated Amorphous Carbon Films etc. can be illustrated.Can as the membrane formation process containing carbon film To utilize the known method such as the vacuum vapour deposition of carbon raw material, sputtering method, ion plating method that employs, to employ the material gas such as hydrocarbon The known method such as the thermal decomposition of body.Film about other can also use vapour deposition method, sputtering method, ion plating method, sol-gal process Etc. film forming.

Prefabricated component makes melten glass through heating, molten raw, the operation forming above-mentioned melten glass And make.

1st making example of prefabricated component is the fused glass block from melten glass separation predetermined weight and cools down, and shapes The method with this fused glass block with the prefabricated component of equal in quality.Such as, frit melted, clarify, homogenize Prepare the melten glass of homogenizing, the mass flowing nozzle made from the platinum or platinum alloy that have adjusted temperature or outflow pipeline stream Go out.In the case of small-sized prefabricated component, spherical prefabricated component are formed, melten glass is dripped expectation from mass flowing nozzle The melten glass of quality drips, and accepts it by prefabricated component finishing die and is configured to prefabricated component.Or, by same desired qualities Melten glass drips and drips to be configured to prefabricated component in liquid nitrogen etc. by mass flowing nozzle.In the case of the most large-scale prefabricated component, Making melten glass stream flow down from flowing out pipeline, accept the leading section of melten glass stream with prefabricated component finishing die, melten glass stream exists After forming necking part between nozzle and prefabricated component finishing die, prefabricated component finishing die is made to decline suddenly to underface, by melted The surface tension of glass from melten glass stream, accepts the fused glass block of desired qualities at necking section at member to undertake, shapes For prefabricated component.Or, it is also possible to glass blocks is suppressed in the period being in soft state on prefabricated component finishing die, is configured to tool The prefabricated component having and to be smoothed by the surface of the shape that the shape of the optical element that precise press molding obtains approximates.

In order to be made without the prefabricated of the smooth surface such as Free Surface of scar, dirt, wrinkle, envenomation etc. Part, makes with the following method etc.: on prefabricated component finishing die etc., fused glass block is applied blast and makes it float while becoming Shape is prefabricated component, under room temperature, normal pressure, gaseous matter cooling is become addition melten glass in the medium of liquid at liquid nitrogen etc. Drip and be configured to prefabricated component.

In the case of making fused glass block float while being configured to prefabricated component, to fused glass block blowing gas (being referred to as floating gas) applies blast upwards.At this moment, if the viscosity of fused glass block is too low, then floats gas and enter glass In glass, in prefabricated component, become bubble and remain.But, it is 3～60dPa s by the viscosity making fused glass block, floats gas Body will not enter in glass and glass blocks can be made to float.

The gas used to the floating gas of prefabricated component as winding-up can enumerate air, N₂Gas, O₂Gas, Ar gas, He Gas, steam etc..As long as additionally, if prefabricated component not solid contact with finishing die surface etc. just can float, blast does not has It is particularly limited to.

The precise press molding product (such as optical element) manufactured by prefabricated component are right owing to having rotation as lens The element claiming axle is more, and therefore the shape of prefabricated component is it is also preferred that have the shape of rotation axes of symmetry.

Prefabricated component the 2nd making example, be cast to mold forms by the melten glass of homogenizing after, by annealing Remove the stress birfringence of formed body, carry out cutting off or severing is to be divided into the size of regulation, shape, make multiple sheet glass, Polished glass sheet makes the method that surface is smooth and is constituted prefabricated component by the glass of definite quality.Preferably in so making Preform surfaces also covers and uses containing carbon film.

[optical element]

Optical element then for a mode of the present invention illustrates.

The optical element of one mode of the present invention is made up of the optical glass of the invention described above mode.Specifically Non-spherical lens, spherical lens or planoconcave lens, planoconvex lens, biconcave lens, biconvex lens, convex falcate can be illustrated The lens of lens, recessed meniscus lens etc., lenticule, lens arra, lens with diffraction grating, prism, with lens merit The prism etc. of energy.Antireflection film can also be arranged as required on surface, there is the partially reflective film of wavelength selectivity.

The optical glass of one mode of the present invention can be to have high index of refraction high dispersivity, Δ Pg, the glass that F is little, Therefore the optical element combination constituted by the optical element of the present invention that this optical glass is constituted and other glass, thus The chromatic aberration correction of high-order can be carried out.Additionally, the optical element of the present invention mode is made up of the glass that refractive index is high, because of This can make optical system densification by using in image pickup optical system, projection optics system etc..

[manufacture method of optical element]

Manufacture method then for the optical element of a mode of the present invention illustrates.

The manufacture method of the optical element of one mode of the present invention possesses: by heating a mode of the invention described above Preform for precise press molding, use compression forming mould carry out precise press molding and obtain the operation of optical element.

In order to prevent the forming face of compression forming mould or be arranged on the oxidation of mold release film of above-mentioned forming face, preferably at nitrogen The non-oxidizing gas environment of the mixed gas etc. of gas or nitrogen and hydrogen carries out the heating of compression forming mould and prefabricated component And suppression process.In non-oxidizing gas environment, cover the most not oxidized containing carbon film of preform surfaces, be pressed in precision The above-mentioned film of formed products remained on surface after shape.This film is the film that finally should remove, in order to be easier and fully remove to contain Carbon film, heats precise press molding product the most in an atmosphere at oxidative environment.Oxidation containing carbon film, removing should be in essence The temperature that close compressing product do not deform due to heating is carried out.And specifically, it is preferable in the temperature of not enough glass transition temperature In the range of carry out.

In precise press molding, prefabricated component be heated after importing compression forming mould together with finishing die also can, will be pre- The compression forming mould that the prefabricated component that first heats imports in compression forming mould, preferably preheated carries out precise press molding also Can.

In all modes, it is all the compression forming mould using and in advance forming face high accuracy being processed into intended shape, but Can also be formed for improving when compressing the film to the smoothness of glass in forming face.Carbon containing is enumerated as such film Film, nitride film, noble metal film, as containing the preferred Soft Hydrogenated Amorphous Carbon Films of carbon film, carbon film etc..Precise press molding in the former mode In, after critically having been carried out supplying prefabricated component between a pair upper die and lower die in opposite directions of shape processing to forming face, excellent The viscosity choosing glass is equivalent to 10⁵～10⁹Till the temperature of dPa s, thermoforming mould and prefabricated component make prefabricated component soft Change, by it is carried out press molding, such that it is able to the forming face of finishing die is critically transferred to glass.

In the precise press molding of the mode of the latter, forming face is critically carried out in opposite directions the one of shape processing Between upper die and lower die, supply is warmed up to the viscosity of glass the most in advance and is equivalent to 10⁴～10⁸The temperature of dPa s prefabricated Part, carries out press molding to it, thus the forming face of finishing die can be critically transferred to glass.

Pressure and time during pressurization can consider that the viscosity etc. of glass suitably determines, such as can be set as pressing pressure is About 5～15MPa, the press time is 10～300 seconds.As long as the pressing conditions of press time, pressing pressure etc. coordinates formed products Shape, size suitably sets in the range of known.

Afterwards, cooling forming mould and precise press molding product, preferably carry out when soon arriving the temperature of below strain point The demoulding also takes out precise press molding product.Further, in order to optical characteristics critically being mated desired value, it is also possible to suitably adjust The annealing conditions of formed products during cooling, such as annealing speed etc..

The precise press molding of the former mode is in the case of paying attention to improving the forming accuracy such as surface accuracy, eccentric precision The method recommended.The precise press molding of the mode of the latter is the method recommended in the case of paying attention to improving productivity ratio.

Further, the optical element of the present invention mode can also make without compressing operation.Such as, will The melten glass of homogenizing is cast in mold be configured to glass blocks, removes stress birfringence and the folding with glass carrying out annealing The rate of penetrating obtains after the mode of desired value adjusts the adjustment that annealing conditions carries out optical characteristics, cutting off or severing glass blocks system Make sheet glass, be ground further, polished optical element, thus can get above-mentioned optical element.

Embodiment

Then, described in detail the present invention by embodiment further, but the present invention is not carried out the side shown in example Formula is limited.Additionally, by with reference to embodiment set forth below, apply the adjusting method of the content of above-mentioned each glass ingredient, thus Can be to obtain the optical glass of a mode of the present invention.

(embodiment 1)

First, in the way of obtaining there is the oxide glass that 43 shown in table a kind form (cation % represents), as The nitrate of raw material use, sulfate, hydroxide, oxide, boric acid etc., weighing each material powder is sufficiently mixed, system Become mediation raw material, this mediation raw material is put in platinum crucible or platinum alloy crucible and carry out heating, melting with 1300 degree, carry out The melten glass of homogenizing is made in clarification, stirring.

This melten glass is flowed in the mold preheated and cools down rapidly, the temperature near glass transition temperature After degree keeps 2 hours, carry out Slow cooling, obtain the oxide glass with 43 shown in table a kind composition.At all of glass Glass does not the most find the optic inhomogeneous parts such as being mixed into of the impurity such as crystallization or platinum field trash, striped.

It addition, the anion component of the whole oxide glasses shown in table 1 is entirely O^2-.The oxide conversion of above-mentioned glass Glass composition represent with a mole % in table 2, represent by quality % in table 3.It addition, the glass composition that table 2, table 3 are recorded It is to form, based on the glass described in table 1, the composition calculated.

The characteristic of each glass is measured by method shown below.Measurement result is shown in Table 1.

(1) refractive index nd and Abbe number vd

The optical glass cooled down with the cooling rate of per hour 30 DEG C is measured.

(2) relative partial dispersion Pg, F, the poor Δ Pg, F of the datum line away from relative partial dispersion

Relative partial dispersion Pg, F be the optical glass cooled down with the cooling rate of per hour 30 DEG C is measured refractive index ng, NF, nc, calculate according to these values.

The poor Δ Pg, F of the datum line away from relative partial dispersion is according to relative partial dispersion Pg, F and by Abbe number ν d calculation Relative partial dispersion Pg, F (0) on the datum line gone out calculates.

(3) glass transition temperature Tg

Use Differential Scanning Calorimetry analytical equipment (DSC), be measured under conditions of programming rate 10 DEG C/minute.

(4) liquidus temperature

Glass is put into be heated to set point of temperature stove keep 2 hours, with the observation by light microscope of 100 times after cooling Inside glass, determines liquidus temperature according to there being nodeless mesh.

(5) proportion

It is measured by Archimedes method.

(6)λ70、λ5

Use is polished to the glass specimen with the face being parallel to each other of the thickness of 10.0 ± 0.1mm, passes through spectrophotometric Count from the light of face vertical direction incident intensity Iin relative to above-mentioned polishing, intensity I out of the light measuring transmissive test, calculate Light transmittance Iout/Iin, is set to λ 70 by the wavelength that light transmittance is 70%, is set by the wavelength that light transmittance is 5% For λ 5.

(7) superficial devitrification test

To be in than liquidus temperature more than the temperature of low 50 DEG C and the model below the temperature of high 50 DEG C than liquidus temperature The metal material that glass melts in enclosing is put with ambient temperatare contacts, after making glass cooling, solidification, with optical microscope (again Rate 100 times) position that contacts with metal material of amplifying observation glass, the crystallization number that measurement glass surface separates out, calculate per unit The crystallization number (surface density) of area.

Further, glass specimen is approximately parallelepiped body, be 25mm × 20mm × 15mm approximately parallelepiped body (volume be about 7500mm³)。

The surface density of the crystallization number in the superficial devitrification test of each glass shown in table 1.The least expression of value more suppresses table Face devitrification.

(8) test with melting of test board

On the smooth face of the test board with smooth surface constituted at the material taking carbon content rate as 50 more than atom % Place glass, heat glass together with test board, after heating-up temperature keeps, be cooled to room temperature, check for test Dish melts with glass.The heating-up temperature of glass is set to the viscosity of glass and becomes 10⁷The temperature of dPa s, the retention time is set to 20 Minute.

Having carried out testing with melting of test board for each glass shown in table 1, each glass does not all occur and test board Melt.

[table 1]

[table 2]

[table 3]

(embodiment 2)

Platinum container is used to make each glass that table 1 is recorded similarly to Example 1.In the present embodiment at the end of platinum container Portion is provided with the outflow pipeline of platinum, after carrying out the melting of glass by known method, clarify, homogenize, from flowing out pipeline even Flow out the melten glass of homogenizing continuously and be cast in mold, be configured to glass blocks, anneal afterwards, cut off and obtain multiple glass Glass sheet.These sheet glass are ground, polish the prefabricated component that the various optical glass made as shown in Table 1 are constituted.Obtain The prefabricated component that prefabricated component is the optically high-quality of homogenizing.

Further, the batch materials being used as mediation multiple compounds as frit and obtaining, it is possible to use will criticize Content of starting materials substantially melts (rough melt) and vitrified cullet material.

(embodiment 3)

The nozzle in thin footpath is then installed in the front end flowing out pipeline, carries out frit similarly to Example 2 melted, clear Clearly, homogenize, from the front end of above-mentioned nozzle succeedingly fractional melting glass drop, use multiple finishing die succeedingly to accept melted Glass drop and be configured to prefabricated component.It is configured to during prefabricated component from finishing die injection gas to glass being dripped by melten glass Block applies the state that the blast of upward direction maintains glass blocks to float.Next it is being cooled to the temperature that prefabricated component does not deforms After degree region, from finishing die, take out prefabricated component, obtain multiple prefabricated component in succession.Further, can in the shaping of above-mentioned prefabricated component To use known forming device.So make the prefabricated component that various optical glass as shown in Table 1 are constituted.Obtain is prefabricated Part is the prefabricated component of the optically high-quality of homogenizing, does not find the precipitation of crystallization on surface and inside.Further, it is former as glass Material is used as batch materials obtained by mediation multiple compounds, it is possible to use batch materials substantially melts (rough melt) And vitrified cullet material.

(embodiment 4)

As required the preform surfaces made in embodiment 2,3 is applied plating, import to be included in forming face and set It is equipped with in the upper and lower mould of the SiC of carbons mold release film and the compression forming mould of body mould, by finishing die and prefabricated component under nitrogen environment Heating makes prefabricated component soften together, carries out precise press molding and has made the convex falcate of aspheric surface being made up of above-mentioned various glass The recessed meniscus lens of lens, aspheric surface, aspheric surface biconvex lens, the various lens of aspheric surface biconcave lens.Further, accurate compacting The each condition shaped is adjusted in aforementioned range.

When observing the various lens so made, at lens surface entirely without finding scar, opaque, damaged.

Such process is repeated, has carried out the volume production test of various lens.Same compression forming mould is used repeatedly to enter Go the precise press molding of more than 400 times, the fault such as melt of glass and compression forming mould has not occurred, can be accurately Produce surface and the internal lens being high-quality.

Can also plating antireflection film on the surface of the lens so obtained.

Then, heat, soften the element identical with above-mentioned prefabricated component, import to other pre-heated compression forming mould, Carry out precise press molding and make the aspheric surface male bend moon-shaped lens, the recessed bent moon of aspheric surface that are made up of above-mentioned various glass Shape lens, aspheric surface biconvex lens, the various lens of aspheric surface biconcave lens.Further, each condition of precise press molding is front Adjusted in the range of stating.

When observing the various lens so made, do not find the nebulousurine that split-phase causes, entirely without at lens surface Find scar, opaque, damaged.

Such process is repeated and has carried out the volume production test of various lens.Same compression forming mould is used repeatedly to enter , there is not the fault such as melt of glass and compression forming mould, can give birth to accurately in the precise press molding that row is more than 400 times Produce surface and the internal lens being high-quality.

Can also plating antireflection film on the surface of the lens so obtained.

Alternatively, it is also possible to suitably change the shape of the forming face of compression forming mould, make prism, lenticule, lens array The various optical elements such as row.

(comparative example 1)

Then, by the optical glass No.7 (hereinafter referred to as glass A) described in the table 2 of the document 2 recorded before, document 4 The optical glass No.24 (hereinafter referred to as glass B) described in table 1 and No.25 (hereinafter referred to as glass C), document 5 table 1 in Record optical glass No.5 (hereinafter referred to as glass D), document 6 table 1-1～table 1-5 record oxide glass No.2 (with Down be referred to as glass E) each glass, utilize the method described in each document to make.

Then, for these glass A～E, melted by above-mentioned method test board and tested.Result glass A ～E all melts with test board.

Then multiple preform for precise press molding being made up of each glass of glass A～E is made.Use these prefabricated Part is repeated precise press molding with method similarly to Example 4, and investigation occurs the pressure that glass and compression forming mould melt Number of times processed.About glass A～C, it is possible to the number of times carrying out precise press molding is 50～90 times, about glass D, E, it is possible to carry out The number of times of precise press molding is 30～80 times.The composition of glass A～C, characteristic, melt the result of test, accurate pressure can be carried out Make the number of times of shape, as shown in table 4.

In glass A～E, cation ratio (Ta⁵⁺/(Ti⁴⁺+Ta⁵⁺)) maximum glass is glass A, its value is 0.20.Separately On the one hand, in the glass that table 1 is recorded, cation ratio (Ta⁵⁺/(Ti⁴⁺+Ta⁵⁺)) minimum glass be No.1, No.21, No.22, their value is 0.25.

Glass A～E melts with test board in melting test, can carry out the number of times of precise press molding less than 100 Secondary.In contrast, at cation ratio (Ta⁵⁺/(Ti⁴⁺+Ta⁵⁺)) be 0.25 above-mentioned each glass in, melt test in not with examination Testing hair updo life to melt, can carry out precise press molding number of times is more than 400 times.According to above result, it is known that by make sun from Son is than (Ta⁵⁺/(Ti⁴⁺+Ta⁵⁺)) it is more than 0.23, the number of times that can carry out precise press molding can be dramatically increased.

Glass A～E is the optical glass having high refractive index of precise press molding difficulty, it is possible to be carried out continuously 30～90 precisions Compressing, but compare with the test result of embodiment 4, the number of times that can be carried out continuously precise press molding is greatly decreased.

[table 4]

(comparative example 2)

About each glass of optical glass No.1～No.51 recorded as embodiment in the document 3 recorded before, use The method stated carries out superficial devitrification test, and in all of glass, the surface density of crystallization number is more than 10⁴Individual/cm²。

And then, make fused glass block float and shape, make multiple optical glass No.26 recorded by document 3 The preform for precise press molding constituted.Further, the volume of prefabricated component is 800mm³.As a result, at prefabricated component more than half Surface find crystallization, produce yield rate less than 50%.It is also carried out about other glass beyond optical glass No.26 Same test, has obtained identical test result.

(embodiment 5)

Use each lens made in embodiment 4, make the exchange lens of the slr camera being built-in with each lens.Enter And use each lens made in embodiment 4 to make the various optical systems of portable digital camera so that it is modularity.And then The imageing sensor of CCD or CMOS etc. is installed in these optical systems so that it is modularity.

Like this by using the various lens made in example 4, the optical system of high function, densification can be obtained System, exchange lens, lens module, camera head.Saturating by lens and the low-dispersion optical glass for mold that will make in embodiment 4 Mirror combines, and can obtain the aberration various optical systems being corrected and the camera head possessing this optical system of high-order.

Finally sum up the optimal way of present embodiment.

The optimal way of present embodiment is O^2-Content is the optical glass of more than 98 aniones %.

And then another optimal way is Zn²⁺The optical glass that content is more than 5%, more preferably Zn²⁺Content It is the optical glass of more than 8%.

And then another optimal way is cation ratio (Zn²⁺/(Zn²⁺+Mg²⁺)) be more than 0.6 optical glass.

And then the content that another optimal way is Yb is by the Yb in the glass composition of oxide benchmark₂O₃Amount be not enough The optical glass of 2.0 mass %.

And then another optimal way is cation ratio ((Nb⁵⁺+Ta⁵⁺)/(Ti⁴⁺+Nb⁵⁺+Ta⁵⁺+W⁶⁺+Bi³⁺)) it is 0.01 Above optical glass.

And then another optimal way is cation ratio ((Nb⁵⁺+Ta⁵⁺)/(Ti⁴⁺+Nb⁵⁺+Ta⁵⁺+W⁶⁺+Bi³⁺)) it is not enough The optical glass of 0.7.

And then another optimal way is cation ratio (Ti⁴⁺/(Ti⁴⁺+Nb⁵⁺+Ta⁵⁺+W⁶⁺+Bi³⁺)) it is less than 0.43 Optical glass.

And then another optimal way is cation ratio ((Ti⁴⁺+Nb⁵⁺+Ta⁵⁺+W⁶⁺+Bi³⁺)/(La³⁺+Gd³⁺+Y³⁺+Yb³ ⁺)) it is the optical glass of 0.40～4.00.

And then another optimal way is cation ratio (Te⁴⁺/(Zn²⁺+Mg²⁺)) it is the optical glass less than 1.0.

And then the content that another optimal way is Ge is by the GeO in the glass composition of oxide benchmark₂Amount be not enough The optical glass of 5.0 mass %.

And then another optimal way be liquidus temperature be the optical glass of less than 1250 DEG C.

And then another optimal way be have utilize said method with test board melt in test not with test The optical glass of the raw precise press molding melted of hair updo.

And then another optimal way be have utilize said method with test board melt in test not with examination The mode testing the raw precise press molding melted of hair updo determines cation ratio (Ta⁵⁺/(Ti⁴⁺+Ta⁵⁺)) optical glass.

The optical glass that optical glass is the chromatic aberration correction being suitable for high-order of one mode of the present invention, is suitable for system Make preform for precise press molding and optical element.

It is believed that embodiment of disclosure is the most all exemplary rather than limiting.The scope of the present invention is not Represented by the scope of Patent right requirement by above-mentioned explanation, it is intended that above comprise and be equal to scope of the patent claims The meaning and scope in all of change.

Claims

1. an optical glass, it is oxide glass, represents by cation %, comprises:

Add up to the B of 5～60%³⁺And Si⁴⁺, wherein, B³⁺It is 5～50%,

Add up to the Zn of more than 5%²⁺And Mg²⁺,

Add up to the La of 10～50%³⁺、Gd³⁺、Y³⁺And Yb³⁺, and

Add up to the Ti of 6～45%⁴⁺、Nb⁵⁺、Ta⁵⁺、W⁶⁺And Bi³⁺, wherein, Ti⁴⁺And Ta⁵⁺Total content more than 0%, and W⁶⁺ Content more than 5%,

Ta⁵⁺Content relative to Ti⁴⁺And Ta⁵⁺Add up to content cation ratio (Ta⁵⁺/(Ti⁴⁺+Ta⁵⁺)) it is more than 0.23,

Ti⁴⁺、Nb⁵⁺、Ta⁵⁺、W⁶⁺And Bi³⁺Total content relative to B³⁺And Si⁴⁺Add up to content cation ratio ((Ti⁴⁺+Nb⁵ ⁺+Ta⁵⁺+W⁶⁺+Bi³⁺)/(B³⁺+Si⁴⁺)) it is more than 0.39 and less than 3.00,

Zn²⁺、Mg²⁺And Li⁺Total content relative to La³⁺、Gd³⁺、Y³⁺And Yb³⁺Add up to content cation ratio ((Zn²⁺+Mg² ⁺+Li⁺)/(La³⁺+Gd³⁺+Y³⁺+Yb³⁺)) it is more than 0.40,

25≤νd<(3.91-nd)/0.06…(1)。

2. optical glass as claimed in claim 1, wherein, glass transition temperature is less than 650 DEG C.

3. optical glass as claimed in claim 1 or 2, wherein,

The content of Ge presses the GeO in the glass composition of oxide benchmark₂Amount be less than 5.0 mass %, and

Te⁴⁺Content relative to Zn²⁺And Mg²⁺Add up to content cation ratio (Te⁴⁺/(Zn²⁺+Mg²⁺)) it is less than 1.

4. optical glass as claimed in claim 1 or 2, wherein, adds up to the Zn comprising more than 8 cationes %²⁺And Mg²⁺。

5. optical glass as claimed in claim 3, wherein, adds up to the Zn comprising more than 8 cationes %²⁺And Mg²⁺。

6. optical glass as claimed in claim 1 or 2, wherein, the content of Yb is pressed in the glass composition of oxide benchmark Yb₂O₃Amount be less than 2.0 mass %.

7. a preform for precise press molding, is made up of the optical glass according to any one of claim 1～6.

8. an optical element, is made up of the optical glass according to any one of claim 1～6.

9. a manufacture method for optical element, wherein, comprises: used by the precise press molding described in heating claim 7 Prefabricated component, uses compression forming mould to carry out precise press molding and obtain the step of optical element.

10. the manufacture method of optical element as claimed in claim 9, wherein, comprises: pre-being used by described precise press molding The step that it is heated after importing compression forming mould together with this finishing die by product.

The manufacture method of 11. optical elements as claimed in claim 9, wherein, comprises: pre-being used by described precise press molding It is conducted into compression forming mould after product heating, carries out the step of described precise press molding.