CN1099388C - Optical glass having negative abnormal dispersion - Google Patents

Optical glass having negative abnormal dispersion Download PDF

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CN1099388C
CN1099388C CN98105841A CN98105841A CN1099388C CN 1099388 C CN1099388 C CN 1099388C CN 98105841 A CN98105841 A CN 98105841A CN 98105841 A CN98105841 A CN 98105841A CN 1099388 C CN1099388 C CN 1099388C
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glass
composition
less
abnormal dispersion
negative abnormal
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CN1225903A (en
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中原宗雄
森下道子
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Ohara Inc
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Ohara Inc
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Abstract

The present invention relates to optical glass which has large reverse direction anomalous dispersion and has optical constants that the coefficient of reflection rages from 1.55 to 1.75, the Abbe number rages from 25 to 51. The glass basically does not contain lead and arsenic, and contains main essential ingredients of 10 to more than 40 wt % of SiO2, 12.5 to 35 wt % of B2O3, 3 to 20 wt % of ZrO2 and 6 to 30 wt % of Nb2O5.

Description

Opticglass with negative abnormal dispersion
The present invention relates to have optical constant: reflection coefficient (nd) is 25-less than 48.6 for 1.55-less than 1.69, Abb (ν d), and has bigger negative abnormal dispersion (Δ θ g.F) and be substantially free of the opticglass of lead compound and arsenic compound.
As the opticglass with such optical constant and negative abnormal dispersion performance, known have a B 2O 3-Al 2O 3-PbO system glass.Yet the glass of this system requires to use relatively large PbO, and the result makes glass trend towards having higher density and makes chemical durability become insufficient, and owing to these reasons, this glass only has the application that is restricted.As the glass system that does not contain PbO, at Japanese Patent (publication number) 50-18007, in Japanese Patent (publication number) 58-49502 and the German Patent (publication number) 4,032,566 known glass is disclosed.These glass require to use relatively large polyvalent metal oxides or such as Ta 2O 5Oxide compound or a large amount of ZrO 2, Nb 2O 5And Ta 2O 5, giving glass negative abnormal dispersion performance, thereby but this exist again and be difficult to raw material is melted the problem that obtains uniform glass fully.
The opticglass that exploitation has big negative abnormal dispersion is very useful to the design of various opticglass.Ordinary optical glass for not having big negative abnormal dispersion combines the aberration that can remove bi-coloured light by two types the optical lens that Abb is different.Yet consider the light time of other colors, still have the remaining aberration that shows as secondary spectrum.In order to proofread and correct the light of this secondary spectrum, particularly UV spectrum, having extremely with two kinds, the forward of deviation and the different optical lens of negative abnormal dispersion characteristic combine.By such arrangement, can eliminate most secondary spectrums.
The purpose of this invention is to provide a kind of have the big negative abnormal dispersion of opticglass in the prior art of being equal to or greater than and have excellent homogeneity and do not contain concerning environment undesirable compound, as PbO and As 2O 3And do not require very expensive Ta 2O 5The opticglass of component.
The inventor has carried out arduous research and test in order to realize the foregoing invention purpose, and the result has obtained to cause discovery of the present invention, is not promptly having PbO and As basically 2O 3The SiO of specific composition 2-B 2O 3-ZrO 2-Nb 2O 5Can obtain to have big negative abnormal dispersion and higher inhomogeneity opticglass in the glass system.
The opticglass composition (weight percentage) that reaches above-mentioned purpose of the present invention is as follows:
SiO 217-less than 40%
B 2O 3 12.5-33％
ZrO 2 7-18％
Nb 2O 5 6-29％
Li 2O 0-2.5％
Na 2O 4-25％
K 2O 0-5％
MgO+CaO less than 5%
MgO 0-less than 5% wherein
CaO 0-4.8％
SrO 0-5％
BaO 0-19％
ZnO 0-6％
Ta 2O 5 0-10％
P 2O 50-less than 5%
GeO 2 0-5％
SnO 2 0-2％
WO 3 0-5％
Sb 2O 3 0-1％
And one or more fluorochemical that is obtained by displacement in the metallic element in the above-mentioned metal oxide, wherein the total amount of fluorine is in the fluorochemical: 0-3%,
And this glass has optical constant: reflection coefficient (nd) is a 1.55-less than 1.69, and Abb (ν d) is a 25-less than 48.6, and this glass has negative abnormal dispersion.
In the glass of making according to the present invention, owing to following reason, each composition can be selected the content of above-mentioned scope.In the following description, the content range of each composition is represented with weight percent.
SiO 2Composition is necessary composition as forming the glass oxide compound.If this becomes dosis refracta to be lower than 10%, can not obtain stable glass, and if this to become dosis refracta be 40% or higher, the glass-reflected coefficient that is obtained can't fall in the desired scope.In order to obtain the glass of the good and excellent in uniformity of melting properties, this composition preferred range is a 17%-less than 40%.
B 2O 3Composition and SiO 2It equally is important formation glass oxide compound.If this becomes dosis refracta to be lower than 12.5%, viscosity is too high, the relatively poor and negative abnormal dispersion performance reduction of melting properties.If this becomes dosis refracta to surpass 35%, become instability and crystal of glass trends towards growth.In order to obtain good chemical stability and homogeneity, this composition preferred range is 12.5-33%.
ZrO 2Composition can increase the reflection coefficient and the negative abnormal dispersion performance of glass effectively.If this becomes dosis refracta to be lower than 3%, can not fully obtain this effect, and if this becomes dosis refracta to surpass 20%, the non-melt part in the glass trends towards increasing.In order to obtain good melting properties and homogeneity, this composition preferred range is 7-18%.
Nb 2O 5Composition is accommodation reflex coefficient and Abb effectively.If this becomes dosis refracta to be lower than 6%, can not obtain this effect, and if this becomes dosis refracta to surpass 30%, crystallization trend increases and the negative abnormal dispersion degradation, this composition preferred range is 6-29%.
Improve the Li of glass melting performance 2The O composition can be added to and be not more than 5%.Yet because this composition has increased the crystallization trend, this one-tenth dosis refracta is preferably and is not more than 2.5%.Improve the Na of glass melting performance respectively 2O and K 2O can be added to and be not more than 25% and 10%.Because these compositions trend towards destroying chemical durability, preferred range is to NaO 2For 4-25%, to K 2O is for being not more than 5%.
MgO and CaO composition can improve chemical durability and accommodation reflex coefficient and Abb effectively, but have increased the crystallization trend.Therefore the quantity of these compositions should be respectively less than 5%.The total amount of these compositions also should be less than 5%.The SrO composition is the composition of effectively accommodation reflex coefficient and Abb and can be added to and be not more than 15%.Yet because this composition trends towards increasing tendency towards devitrification and destroys chemical durability, preferred range is for being not more than 5%.
The BaO composition can enlarge the vitrifying scope effectively and can be added to and be not more than 20%.Yet, because this composition tends to increase the negative abnormal dispersion of glass, so preferred range is for being not more than 19%.The ZnO composition also can enlarge the vitrifying scope effectively and can be added to and be not more than 15%.Yet, because this composition tends to stop the abundant increase of negative abnormal dispersion, so preferred range is for being not more than 6%.
Ta 2O 5Composition can increase reflection coefficient and negative abnormal dispersion effectively and can be added to and is not more than 15%.Yet, tend in glass, produce unfused part owing to add this composition, cause being difficult to form uniform glass, so preferred range should be not more than 10%.P 2O 5Composition is accommodation reflex coefficient and Abb effectively, but has increased tendency towards devitrification and reduced negative abnormal dispersion, so this becomes the dosis refracta should be less than 5%.
GeO 2Composition is the vitrifying oxide compound and its adding can be used for accommodation reflex coefficient and Abb.Yet, because this composition trends towards increasing tendency towards devitrification, so this becomes dosis refracta should be not more than 5%.SnO 2Composition improves chemical durability, but reduces negative abnormal dispersion, so this becomes dosis refracta should be not more than 2%.
WO 3Composition is accommodation reflex coefficient and Abb and can be added to and be not more than 5% effectively.Surpassing 5% if this composition adds, then is undesirable, because this will increase tendency towards devitrification.The F composition replaces part or all of above-mentioned oxide compound with compound form and can join and be not more than 5%.Yet, owing to this composition trends towards producing streak and increase tendency towards devitrification in glass, so preferred range should be not more than 3%.Sb 2O 3Composition can be used as the defoamer adding and is used for purifying and homogenizing glass.It is not more than 1% quantity just has been enough to.
Opticglass embodiment of the present invention is described with reference to the accompanying drawings.
In the accompanying drawings, Fig. 1 is the θ g.F-ν d curve of expression forward and negative abnormal dispersion (Δ θ g.F).
Fig. 2 is the curve of the partial dispersion rate (θ g.F) of the expression embodiment of the invention (1-25).
Embodiment
Table 1-5 represents embodiment of the invention 1-25, and it has the reflection coefficient (nd) of 1.55-less than 1.69 and the Abb (ν d) and the bigger negative abnormal dispersion of 25-less than 48.6.These tables have been represented composition, reflection coefficient (nd), Abb (ν d), partial dispersion rate (θ g.F) and the negative abnormal dispersion (Δ θ g.F) of these embodiment.
Table 1
Weight %
Embodiment
1 2 3 4 5
SiO 2 33.00 22.30 22.90 22.20 25.90
B 2O 3 14.00 12.90 23.00 13.00 28.00
ZrO 2 13.00 12.40 13.00 12.40 13.00
Nb 2O 5 26.90 25.60 10.00 25.60 10.00
Li 2O
Na 2O 13.00 21.90 7.00 21.90 4.00
K 2O
MgO 4.80
CaO 4.80 4.50
SrO 4.80
BaO 19.00 14.50
ZnO
Al 2O 3
La 2O 3
Sb 2O 3 0.10 0.10 0.30 0.10 0.10
GeO 2
SnO 2
Ta 2O 5
P 2O 5
WO 3
KHF 2
nd 1.67280 1.67633 1.64601 1.68451 1.63565
νd 35.0 35.8 44.2 35.7 46.0
θg.F 0.5788 0.5783 0.5585 0.5781 0.5499
Δθg.F -0.0059 -0.0051 -0.0113 -0.0054 -0.0169
Table 2
Weight %
Embodiment
7 9 10
SiO 2 20.00 22.80 20.00
B 2O 3 15.20 13.50 15.20
ZrO 2 12.40 12.70 12.40
Nb 2O 5 25.60 26.40 25.60
Li 2O
Na 2O 21.90 22.50 21.90
K 2O
MgO
CaO
SrO
BaO
ZnO 4.80
Al 2O 3
La 2O 3
Sb 2O 3 0.10 0.10 0.10
GeO 2
SnO 2 2.00
Ta 2O 5
P 2O 5 4.80
WO 3
KHF 2
nd 1.68538 1.68441 1.66881
νd 34.8 35.0 35.9
θg.F 0.5748 0.5811 0.5779
Δθg.F -0.0102 -0.0036 -0.0053
Table 3
Weight %
Embodiment
11 12 13 15
SiO 2 20.00 25.00 20.00 38.49
B 2O 3 15.20 17.00 15.20 16.79
ZrO 2 12.40 18.00 12.40 9.01
Nb 2O 5 25.60 10.00 25.60 13.92
Li 2O
Na 2O 21.90 23.00 21.90 7.78
K 2O 4.09
MgO
CaO 1.43
SrO
BaO 5.12
ZnO 3.28
Al 2O 3
La 2O 3
Sb 2O 3 0.10 0.10
GeO 2 4.80
SnO 2
Ta 2O 5 4.90
P 2O 5
WO 3 2.00
KHF 2 4.80
nd 1.68171 1.63693 1.66644 1.61366
νd 35.2 41.2 35.9 44.0
θg.F 0.5778 0.5617 0.5768 0.5581
Δθg.F -0.0066 -0.0129 -0.0064 -0.0120
Table 4
Weight %
Embodiment
16 17 18 19
SiO 2 25.00 26.32 39.50 22.92
B 2O 3 17.00 12.63 14.20 23.02
ZrO 2 18.00 13.69 7.70 13.01
Nb 2O 5 14.90 23.05 11.50 10.01
Li 2O
Na 2O 23.00 24.21 7.70 7.01
K 2O 5.00
MgO
CaO 3.00 4.00
SrO
BaO 6.30 14.00
ZnO 5.00 6.00
Al 2O 3
La 2O 3
Sb 2O 3 0.10 0.10 0.10 0.01
GeO 2
SnO 2
Ta 2O 5
P 2O 5
WO 3 2.00
KHF 2
nd 1.64432 1.66366 1.61161 1.66336
νd 39.8 36.8 46.2 45.7
θg.F 0.5676 0.5668 0.5536 0.5563
Δθg.F -0.0807 -0.0150 -0.0129 -0.0110
Table 5
Weight %
Embodiment
23 25
SiO 2 39.90 39.26
B 2O 3 15.70 16.36
ZrO 2 10.70 8.69
Nb 2O 5 11.50 14.01
Li 2O
Na 2O 7.70 7.77
K 2O 5.00 3.48
MgO
CaO 1.33
SrO
BaO 4.81
ZnO 3.37
Al 2O 3
La 2O 3
Sb 2O 3 0.2 0.10
GeO 2
SnO 2
Ta 2O 5 9.30
P 2O 5
WO 3
KHF 2 0.82
nd 1.60745 1.61191
νd 42.2 44.3
θg.F 0.5650 0.5612
Δθg.F -0.0080 -0.0084
At this, partial dispersion rate (θ g.F) is meant (n g-n F) and principal dispersion rate (n F-n C) ratio.In Fig. 1, simple glass F2 and K7 are elected to be reference, Z-axis is represented partial dispersion rate (θ g.F), and transverse axis is represented Abb (ν d), represent the deviation of part scatter coefficient, i.e. negative abnormal dispersion (Δ θ g.F) in two kinds of glass F2 on the Z-axis and K7 and the difference between the line segment that each embodiment links to each other.The value of partial dispersion rate be positioned at two kinds with reference to glass institute line section on the time, this value is represented forward anomalous dispersion (+Δ θ g.F), and the value of partial dispersion rate is when being positioned under this line, this value is represented negative abnormal dispersion (Δ θ g.F).
In Fig. 2, represent the line segment that simple glass F2 links to each other with K7 with solid line.Represent to represent the line segment of negative abnormal dispersion glass in the prior art with chain line, represent the value of the part scatter coefficient of embodiment of the invention 1-25 with stain C.
As show 1-5 and shown in Figure 2, the glass of making according to the present invention has the negative abnormal dispersion (Δ θ g.F) that is equal to or greater than glass of the prior art, has desirable optical constant simultaneously again.
In order to make the glass of embodiment 1-25, will comprise that the opticglass raw material of oxide compound, carbonate and nitrate is weighed, this mixture was melted 3-4 hour under 1300 ℃-1400 ℃ temperature in platinum crucible, this depends on the melting raw materials performance.Glass after stirring and the homogenizing fusing also cools the temperature to suitable temp subsequently.Make glass form glasswork by being cast in the metal die and then annealing.
As previously mentioned, opticglass of the present invention is SiO 2-B 2O 3-ZrO 2-Nb 2O 5The glass of the specific composition of system, it has optical constant: reflection coefficient (nd) is a 1.55-less than 1.69, Abb (ν d) is for 25-less than 48.6 and have bigger negative abnormal dispersion and good homogeneity.

Claims (1)

1. opticglass, by weight percentage, it is composed as follows:
SiO 217-less than 40%
B 2O 3 12.5-33％
ZrO 2 7-18％
Nb 2O 5 6-29％
Li 2O 0-2.5％
Na 2O 4-25％
K 2O 0-5％
MgO+CaO less than 5%
MgO 0-less than 5% wherein
CaO 0-4.8％
SrO 0-5％
BaO 0-19％
ZnO 0-6％
Ta 2O 5 0-10％
P 2O 50-less than 5%
GeO 2 0-5％
SnO 2 0-2％
WO 3 0-5％
Sb 2O 3 0-1％
And one or more fluorochemical that is obtained by displacement in the metallic element in the above-mentioned metal oxide, wherein the total amount of fluorine is in the fluorochemical: 0-3%,
And this glass has optical constant: reflection coefficient (nd) is a 1.55-less than 1.69, and Abb (ν d) is 25 1 less thaies 48.6, and this glass has negative abnormal dispersion.
CN98105841A 1998-02-10 1998-02-10 Optical glass having negative abnormal dispersion Expired - Lifetime CN1099388C (en)

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CN106915901A (en) * 2015-12-25 2017-07-04 株式会社小原 A kind of optical glass, prefabricated component and optical element

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