CN101397187A - Optical glass - Google Patents

Abstract

The invention provides optical glass with high refractive index and low decentralization the imaging performance of which is not easily influenced by the change of temperature of the used environment easily, the refractive index (nd) of which is over 1.75, and abbe number (vd) of which is over 35. SiO2, B2O3 and La2O3 are contained as the necessary components, and the proportion of the components is also adjusted, therefore obtaining the optical glass which realizes that the average coefficient of linear expansion alpha of -30 to +70 DEG C multiplying photoelastic constant beta when the wavelength is 546.1 nm (alpha * beta) is less than 130*10<-12> DEG C<-1>*nm*cm<-1>*Pa<-1>.

Description

Opticglass

Technical field

To the present invention relates to specific refractory power (nd) be more than 1.75 and Abbe number (ν d) to be that high refractive index more than 35 is low disperse opticglass and utilize optical elements such as lens that this opticglass obtains, prism, relate in particular to require high-precision imaging characteristic to be that the high refractive index that is suitable in the projecting lens, prism of the optical apparatus of representative is low with photographic camera or pick up camera, projector disperse opticglass and by its optical element that makes and optical apparatus.

Background technology

The low glass that disperses of high refractive index is very high as the demand of used for optical elements materials such as various lens, as specific refractory power (nd) is more than 1.75 and Abbe number (ν d) is the opticglass more than 35, and known have such various glass compositions of patent documentation 1～3 representative.

In recent years, the digitizing of optical apparatus, height become more meticulous in development, and the optical element that requires to be used for image regeneration (projection) machines such as shooting machine such as digital camera, pick up camera and projector, projection TV has high-performance.Its performance be not only specific refractory power, Abbe number, degree of staining these from just beginning in the past to the characteristic of opticglass requirement, be included in also in the actual environment for use that flutter is few, that opticglass manufacturing, optical element add the man-hour carrying capacity of environment is little.

The reason that imaging characteristic changes in actual environment for use, being presumably optical elements such as lens, prism is fixed in the optical apparatus by anchor clamps etc., along with the temperature variation of environment for use (temperature variation of enclosure interior, at high temperature be used etc.), produce the hot exapnsion of optical element, since different with the exapnsion coefficient of stationary fixture, stress produced in the optical element, the result, produce double refraction in optical element, imaging characteristic changes.

As mentioned above, in the time of can't in actual environment for use, realizing with the imaging characteristic of optical constants such as the specific refractory power that obtains based on certain temperature (mainly being the room temperature degree), Abbe number design, have a negative impact, promptly, must when optical design, suppose environment for use, and the complicated flutter of prediction designs.

Add man-hour at opticglass manufacturing, optical element, if comprise the high compositions of carrying capacity of environment such as lead (Pb) compound, arsenic (As) compound, then can produce in order to prevent that pollution substance from needing disadvantageous effects such as special measure to the diffusion of atmosphere, water quality.In addition, the rare mineral resource of using tantalum representatives such as (Ta) in a large number not only production cost uprise but also need be used for cost, the labor force that resource reclaims.

For the low opticglass that disperses of the high refractive index that in glass is formed, does not contain the high composition of carrying capacity of environment, as patent gazette 1～3 representative, disclose various glass compositions, but do not considered about the change of imaging characteristic in the actual environment for use.

Patent documentation 1: TOHKEMY 2005-306732 communique

Patent documentation 2: TOHKEMY 2002-284542 communique

Patent documentation 3: TOHKEMY 2004-161506 communique

Patent documentation 4: Japanese kokai publication sho 56-160340 communique

Patent documentation 5: Japanese kokai publication sho 52-14607 communique

Summary of the invention

Problem to be solved by this invention

The present invention is based on such fact, provide not to be vulnerable to the imaging characteristic influence that the temperature variation by environment for use causes and specific refractory power (nd) is 1.75 or more and Abbe number (ν d) is the low dispersion of a high refractive index opticglass 35 or more, and need not a large amount of environments for use load high composition and rare mineral resource.

The method that is used to deal with problems

People of the present invention further investigate repeatedly in order to reach aforementioned target, found that by containing SiO ₂, B ₂O ₃, La ₂O ₃As must composition, and adjust the ratio of moiety, the product α * β of the photoelastic constant β in the time of can making the average coefficient of linear expansion α of realization-30～+ 70 ℃ and wavelength 546.1nm is 130 * 10 ^-12℃ ^-1* nm * cm ^-1* Pa ^-1Following high refractive index is hanged down dispersion opticglass and be need not high composition and the rare mineral resource of a large amount of environments for use loads, and reaches aforementioned purpose, thereby has finished the present invention.Shown in it is composed as follows.

Form 1

A kind of opticglass is characterized in that, the product α * β of the photoelastic constant β when-30～+ 70 ℃ average coefficient of linear expansion α of this opticglass and wavelength 546.1nm is 130 * 10 ^-12℃ ^-1* nm * cm ^-1* Pa ^-1Below, wherein, be benchmark with the oxide compound, contain SiO greater than 1.0 quality % and less than 12.0 quality % ₂, contain the B of 8.0～35.0 quality % ₂O ₃, and the ratio SiO of quality % ₂/ B ₂O ₃Greater than 0 and less than 0.6, contain the La of 25.0～50.0 quality % ₂O ₃

Form 2

According to forming 1 described opticglass, it is characterized in that the optical constant that it has, and specific refractory power (nd) is 1.75～2.00, Abbe number (ν d) is 35～55 scope.

Form 3

According to forming 1 or 2 described opticglass, it is characterized in that, with the oxide compound benchmark, also contain 0.0～40.0 quality %Gd ₂O ₃, 0.0～15.0 quality %Y ₂O ₃, 0.0～15.0 quality %ZrO ₂, 0.0～25.0 quality %Ta ₂O ₅, 0.0～18.0 quality %Nb ₂O ₅, 0.0～10.0 quality %WO ₃

Form 4

According to forming each described opticglass in 1～3, it is characterized in that, be benchmark with the oxide compound, contain

0.0～0.1 quality %GeO ₂And/or

0.0～1.0 quality %Yb ₂O ₃And/or

0.0～1.0 quality %Ga ₂O ₃And/or

0.0～1.0 quality %Bi ₂O ₃,

Do not contain lead compound and As such as PbO ₂O ₃Deng arsenic compound.

Form 5

According to forming each described opticglass in 1～4, it is characterized in that the product α * β of the photoelastic constant β when-30～+ 70 ℃ average coefficient of linear expansion α and wavelength 546.1nm is 100 * 10 ^-12℃ ^-1* nm * cm ^-1* Pa ^-1Below.

Form 6

According to forming each described opticglass in 1～5, it is characterized in that the product α * β of the photoelastic constant β when-30～+ 70 ℃ average coefficient of linear expansion α and wavelength 546.1nm is 90 * 10 ^-12℃ ^-1* nm * cm ^-1* Pa ^-1Below.

Form 7

According to forming each described opticglass in 1～6, it is characterized in that, with the oxide compound ratio (Ta of the quality % of benchmark ₂O ₅+ Nb ₂O ₅+ WO ₃)/(Gd ₂O ₃+ Y ₂O ₃) greater than 0.05 and less than 1.30.

Form 8

According to forming each described opticglass in 1～7, it is characterized in that, represent with quality % based on oxide compound, contain

0～5.0%Li ₂O and/or

0～5.0%Na ₂O and/or

0～5.0%K ₂O and/or

0～5.0%Cs ₂O and/or

0～5.0%MgO and/or

0～5.0%CaO and/or

0～5.0%SrO and/or

0～5.0%BaO and/or

0～3.0%TiO ₂And/or

0～3.0%SnO ₂And/or

0～3.0%Al ₂O ₃And/or

0～5.0%P ₂O ₅And/or

0～10.0%ZnO and/or

0～5.0%Lu ₂O ₃And/or

0～3.0%TeO ₂And/or

0～2.0%Sb ₂O ₃And/or

0～3.0％F。

Form 9

According to forming each described opticglass in 1～8, it is characterized in that, be benchmark with the oxide compound, contain the ZnO of less than 2.0 quality %.

Form 10

According to forming each described opticglass in 1～9, it is characterized in that, be benchmark with the oxide compound, contain the Y of less than 3.5 quality % ₂O ₃

Form 11

According to forming each described opticglass in 1～10, it is characterized in that, with the oxide compound benchmark, the ratio (ZrO of quality % ₂+ Ta ₂O ₅+ Nb ₂O ₅)/(SiO ₂+ B ₂O ₃) less than 1.00.

Form 12

According to forming each described opticglass in 1～11, it is characterized in that, be benchmark with the oxide compound, contain the Y of less than 3.5 quality % ₂O ₃, the ratio (ZnO+Y of quality % ₂O ₃)/La ₂O ₃Greater than 0 and less than 0.5, quality % sum ZrO ₂+ Nb ₂O ₅Greater than 5.0% and less than 13.0%.

Form 13

A kind of opticglass is characterized in that, is benchmark with the oxide compound, and this glass contains

SiO greater than 1.0 quality % and less than 10.0 quality % ₂,

15.0～28.0 quality %B ₂O ₃,

28.0～35.0 quality %La ₂O ₃,

25.0～35.0 quality %Gd ₂O ₃,

5.0～9.0 quality %ZrO ₂With

0.1 the ZnO of～less than 2.0 quality % and

0.0～6.0 quality %Ta ₂O ₅And/or

0.0～5.0 quality %Nb ₂O ₅And/or

0.0～1.0 quality %Sb ₂O ₃And/or

0.0 the Al of～less than 1.0 quality % ₂O ₃,

And, ZrO ₂+ Nb ₂O ₅Total greater than 5.0 quality % and less than 13.0 quality %, the optical constant that this opticglass has that specific refractory power (nd) is 1.78～1.83, Abbe number (ν d) is 44～48 scope, the product α * β of the photoelastic constant β when-30～+ 70 ℃ average coefficient of linear expansion α and wavelength 546.1nm is 90 * 10 ^-12℃ ^-1* nm * cm ^-1* Pa ^-1Below.

Form 14

Optical element such as lens, prism, it will form 1～13 glass as starting material.

Form 15

Optical element such as lens, prism, it is by carrying out the processing of hot repressing system and make forming 1～14 glass.

Form 16

Optical apparatus such as photographic camera or pick up camera, projector, it uses to form optical element and the optical substrate material that 1～15 glass is made.

The invention effect

By adopt above-mentioned form, can provide be not vulnerable to imaging characteristic influence that the temperature variation by environment for use causes, specific refractory power (nd) is 1.75 or more and Abbe number (ν d) is that high refractive index 35 or more is hanged down dispersion opticglass.

Embodiment

Describe for opticglass of the present invention.

The opticglass of aforementioned component 1 is characterized in that, the product α * β of the photoelastic constant β when-30～+ 70 ℃ average coefficient of linear expansion α and wavelength 546.1nm is 130 * 10 ^-12℃ * nm * cm ^-1* Pa ^-1Below, the variable quantity of imaging characteristic under the index expression environment for use of this α * β.Be described more specifically, average coefficient of linear expansion α is big more, means the temperature variation with respect to environment for use, and the exapnsion rate (volume change) of optical element is big more, thereby, mean in to produce bigger thermal stresses with fixed optical elements such as anchor clamps.In addition, photoelastic constant β is big more, means that the double refraction that is produced by the thermal stresses that produces is big more, therefore just enlightens out, and α * β is more little, and then the variation of the imaging characteristic under the environment for use is few more.

In addition, be 130 * 10 by α * β ^-12℃ ^-1* nm * cm ^-1* Pa ^-1Below, there is following advantage: even in actual environment for use, produce imaging characteristic desired when also easily realizing optical design under the situation of temperature variation.

In order to realize that high refractive index is hanged down the product α * β of dispersion opticglass is 130 * 10 ^-12℃ ^-1* nm * cm ^-1* Pa ^-1Below, form in 1, it is characterized in that, contain SiO greater than 1.0 quality % and less than 12.0 quality % ₂, contain 8.0～35.0 quality %B ₂O ₃, and, the ratio SiO of quality % ₂/ B ₂O ₃Greater than 0 and less than 0.6, contain 25.0～50.0 quality %La ₂O ₃

If each composition is described, SiO then ₂Composition has the glass that promotes that formation is stable, and suppresses the effect of the preferred devitrification (appearance of crystallisate) of opticglass, arteries and veins reason (ununiformity of glass inside), but surplus contains SiO ₂During composition, then there is the tendency that specific refractory power (nd) easily diminishes, photoelastic constant β enlarges markedly, consequently be difficult to obtain desired characteristic, thereby, be limited on it less than 12.0 quality %, more preferably 11.5 quality %, most preferably be 11.0 quality %, its lower limit be preferably greater than 1.0 quality %, more preferably 1.2 quality % above, most preferably be more than the 1.4 quality %.SiO ₂Composition can contain with raw material form arbitrarily, preferably with oxide compound (SiO ₂), K ₂SiF ₆, Na ₂SiF ₆Form import.

B ₂O ₃Composition and SiO ₂Composition is to form stable glass and realize the little indispensable composition of average coefficient of linear expansion in order to promote equally.But, if its amount is very few, then there is the tendency that is difficult to obtain stable glass, if its amount is too much, then there is the tendency that specific refractory power (nd) easily diminishes, photoelastic constant β enlarges markedly, consequently be difficult to obtain desired characteristic.Its upper limit be preferably 35 quality %, more preferably 34 quality %, most preferably be 33 quality %, lower limit be preferably 8.0 quality %, more preferably 8.5 quality %, most preferably be 9.0 quality %.B ₂O ₃Composition can H ₃BO ₃, Na ₂B ₄O ₇, Na ₂B ₄O ₇10H ₂O, BPO ₄Contain Deng the raw material form, preferably with H ₃BO ₃Form import.

In addition, by making the ratio SiO of quality % ₂/ B ₂O ₃Greater than 0 and less than 0.6, not only can obtain the effect that the stability of the meltbility of raw material and glass increases, but also the effect that the average coefficient of linear expansion α that can be inhibited increases.Last not only average coefficient of linear expansion α increases in limited time when surpassing, and can to produce slag during glass melting (mainly be to comprise SiO ₂Difficult meltbility crystallization), the productivity variation produces detrimentally affect to inside quality.The scope of the ratio of preferred quality % is 0.03～0.59, most preferably be 0.05～0.58 scope.

La ₂O ₃Composition improves specific refractory power except having, reduces to disperse (it is big that Abbe number becomes) effect the effect that photoelastic constant β is reduced.Yet, when surplus contains, the significantly unstable and easy devitrification of glass.Therefore, the upper limit be preferably 50 quality %, more preferably 49.5 quality %, most preferably be 49.0 quality %, lower limit be preferably 25 quality %, more preferably 25.5 quality %, most preferably be 26 quality %.La ₂O ₃Composition can contain with raw material form arbitrarily, but preferably with oxide compound (La ₂O ₃), nitrate and nitrate hydrate (La (NO ₃) ₃XH ₂O (X is an arbitrary integer)) form imports.

The opticglass of aforementioned component 2 is characterized in that, the optical constant that it has, and specific refractory power (nd) is 1.75～2.00, Abbe number (ν d) is 35～55 scope, and this opticglass is useful to various optical elements and optical design.

Above-mentioned optical constant particularly (makes the thin slice lens also can obtain the amount of refraction of bigger light even if specific refractory power is the characteristic of the high refractive index more than 1.75 from optics system Miniaturizable.Even if being the low dispersing characteristic more than 35, Abbe number make simple lens also can reduce depart from (aberration) of focus that light wavelength causes.) reason set out, useful in optical design.

In the opticglass of aforementioned component 1 and 2, Gd ₂O ₃Composition and La ₂O ₃Composition has the specific refractory power of raising equally, reduces the dispersive effect, but if surplus contains, then with La ₂O ₃Composition is same, and devitrification easily takes place.Therefore, its higher limit be preferably 40 quality %, more preferably 39 quality %, most preferably be 38 quality %.Gd ₂O ₃Composition can import with raw material form arbitrarily, but preferably with oxide compound (Gd ₂O ₃) or fluorochemical (GdF ₃) form import.

Y ₂O ₃Composition has the specific refractory power of adjusting and dispersive effect, when surplus contains, may can not get desired optical constant.Its higher limit be preferably 15 quality %, more preferably 14.5 quality %, most preferably be 14.0 quality %.Y ₂O ₃Composition can import with raw material form arbitrarily, but preferably with oxide compound (Y ₂O ₃) or fluorochemical (YF ₃) form import.

In addition, if then do not have special detrimentally affect technically in aforementioned range, but because Y ₂O ₃Be in the composition that can realize the low dispersing characteristic of high refractive index, to be the rarest mineral wealth, thereby consider under the situation of manufacturing cost, preferred less than 3.5 quality %.

ZrO ₂Composition can be improved specific refractory power (nd), improve the effect of devitrification resistance, but because ZrO ₂Composition is a difficult molten component, thereby when surplus contains, must at high temperature fuse when making glass, and energy loss becomes problem easily.On the other hand, by containing with specified amount, the effect of the devitrification that also can be inhibited.Therefore, the upper limit be preferably 15 quality %, more preferably 13 quality %, most preferably be 12 quality %, lower limit be preferably 1 quality %, more preferably 2 quality %, most preferably be 3 quality %.In addition, even do not adding ZrO ₂Composition can not produce in glass under the situation of devitrification yet, can not contain ZrO ₂Composition.ZrO ₂Composition can import with raw material form arbitrarily, but preferably with oxide compound (ZrO ₂) and fluorochemical (ZrF ₄) form import.

Ta ₂O ₅Therefore can be improved specific refractory power and make the effect of stabilization of composition can contain arbitrarily.But, Ta ₂O ₅Composition is the rare mineral resource, and the cost of material height, is difficult molten component, must high-temperature digestion when making glass, thereby not only production cost increases but also has the characteristic that photoelastic constant β is increased, thereby the upper limit of its content is preferably 25 quality %.Preferred higher limit is that 22 quality %, most preferred higher limit are 19 quality %.Ta ₂O ₅Composition can import with raw material form arbitrarily, but preferably with oxide compound (Ta ₂O ₅) form import.

Nb ₂O ₅Composition and Ta ₂O ₅Composition is same, and the specific refractory power that can be improved also makes the effect of stabilization, therefore can contain arbitrarily with the scope of 0～18 quality %.But, because Nb ₂O ₅Composition is a difficult molten component, necessary high-temperature digestion when making glass, thereby not only production cost increases, but also have the characteristic that photoelastic constant β is increased, therefore, the upper limit of its content is preferably 18 quality %.Preferred higher limit is that 16 quality %, most preferred higher limit are 14 quality %.Nb ₂O ₅Composition can import with raw material form arbitrarily, but preferably with oxide compound (Nb ₂O ₅) form import.

WO ₃Composition has the effect of regulating specific refractory power and dispersion and improving the devitrification resistance of glass.But if surplus contains, then the painted of glass becomes significantly, and so the transmitance step-down of visible-short wavelength zone (not enough 500nm) particularly is not preferred.Therefore, the upper limit be preferably 10 quality %, more preferably 8 quality %, most preferably be 6 quality %.WO ₃Composition can import with raw material form arbitrarily, but preferably with oxide compound (WO ₃) form import.

In the opticglass of aforementioned component 4, for the viscosity of regulating specific refractory power and regulating melten glass, GeO ₂Composition can add arbitrarily in the scope of 0.0～0.1 quality %, but because it is rare mineral resource and price height, does not therefore preferably contain fully.Can add Yb arbitrarily in order to regulate specific refractory power ₂O ₃, Ga ₂O ₃, Bi ₂O ₃Each composition, but because it has the character that photoelastic constant β is increased, so be limited to 1.0 quality % on it.Yet because these compositions also are the rare mineral resources, thereby preferred higher limit is 0.5 quality %, most preferably is fully and does not contain.GeO ₂, Yb ₂O ₃, Ga ₂O ₃, Bi ₂O ₃Each composition raw material form arbitrarily imports, but preferably with oxide compound (GeO ₂, Yb ₂O ₃, Ga ₂O ₃, Bi ₂O ₃) form import.

Because lead compound and As such as PbO ₂O ₃Deng arsenic compound is the high composition of carrying capacity of environment, thereby except inevitably sneaking into, expectation does not contain fully.

Aforementioned component 5 and forming in 6 the opticglass, in order to be used for the optical element of high precision more and high meticulous purposes, product α * β is preferably 100 * 10 ^-12℃ ^-1* nm * cm ^-1* Pa ^-1Below, most preferably be 90 * 10 ^-12℃ ^-1* nm * cm ^-1* Pa ^-1Below.

The value of this α * β is more little, the faithful to more optical design value of calculating based near the optics physics value the room temperature of the imaging characteristic under the then actual environment for use, thereby have the advantage that need on the basis of the various environments for use of supposition, not implement complicated optical analogy.

In the opticglass of composition 7, by improving the strong Ta of dispersive effect ₂O ₅, Nb ₂O ₅, WO ₃Total amount with can obtain reducing the Gd of dispersive effect ₂O ₃, Y ₂O ₃The ratio (Ta of quality % of total amount ₂O ₅+ Nb ₂O ₅+ WO ₃)/(Gd ₂O ₃+ Y ₂O ₃) be controlled at greater than 0.05 and the scope of less than 1.30, realize desired Abbe number (35～55) easily, thereby preferred aforesaid scope.More preferably 0.055～1.29, most preferably be 0.06～1.28 scope.

In the opticglass of aforementioned component 8,, can stably realize forming 1～7 described characteristic by containing the composition of described scope.Qualification reason for each composition describes.

Alkalimetal oxide composition (Li ₂O, Na ₂O, K ₂O, Cs ₂O) can the be improved effect of glass melting, thereby can contain arbitrarily, but if contain in a large number, be easy to generate then that evenly heat exapnsion factor alpha increases, specific refractory power reduces easily, glass unstable and preferred phenomenon such as devitrification takes place, thereby, % represents with quality, respectively preferably in 0.0～5.0% scope.Preferred higher limit is Li ₂O composition and Na ₂O composition and K ₂The O composition is 4.5%, Cs ₂The O composition is 4.0%.The most preferred upper limit is Li ₂The O composition is 2.0%, Na ₂O, K ₂O, Cs ₂The O composition does not contain fully.The alkalimetal oxide composition can be with carbonate (Li ₂CO ₃, Na ₂CO ₃, K ₂CO ₃, Cs ₂CO ₃), nitrate (LiNO ₃, NaNO ₃, KNO ₃, CsNO ₃), fluorochemical (LiF, NaF, KF, KHF ₂), composite salt (Na ₂SiF ₆, K ₂SiF ₆) wait various forms to import, but preferably import with carbonate and/or nitrate.

Alkaline earth metal oxide composition (MgO, CaO, SrO, BaO) can adjusted glass specific refractory power and the effect of photoelastic constant, thereby can contain arbitrarily, but if contain in a large number, then be difficult to realize desired optical constant (particularly specific refractory power), thereby represent with quality %, respectively preferably in the scope of 0.0～5.0 quality %.Preferred higher limit is that MgO composition and CaO composition are 4.0%, SrO composition and BaO composition are 4.5%.Most preferred higher limit be do not contain fully that MgO composition, CaO composition are 3.0%, SrO composition and BaO composition be 4.0%.The alkaline earth metal oxide composition can be with carbonate (MgCO ₃, CaCO ₃, BaCO ₃), nitrate (Sr (NO ₃) ₂, Ba (NO ₃) ₂), fluorochemical (MgF ₂, CaF ₂, SrF ₂, BaF ₂) wait various forms to import, but preferred form importing with carbonate and/or nitrate and/or fluorochemical.

In order to regulate specific refractory power and Abbe number, can contain TiO arbitrarily ₂Composition, but if surplus contains, then the painted of glass becomes significantly easily, has the especially tendency of the transmitance variation of visible short long (500nm is following).Therefore, preferred higher limit is that 3.0 quality %, preferred higher limit are that 2.5 quality %, most preferred higher limit are 2.0 quality %.TiO ₂Composition raw material form arbitrarily imports, but preferably with oxide compound (TiO ₂) form import.

SnO ₂Composition can be inhibited melten glass oxidation, clarifying effect, prevent effect to light-struck transmitance variation, therefore can contain arbitrarily, but if surplus contains, then might be because the reduction of melten glass cause glass coloring, and fusion equipment precious metals such as (particularly) Pt alloying.The upper limit be preferably 3.0 quality %, more preferably 2.0 quality %, most preferably be 1.0 quality %.SnO ₂Composition can import with raw material form arbitrarily, but preferably with oxide compound (SnO, SnO ₂), fluorochemical (SnF ₂, SnF ₄) form import.

Al ₂O ₃Composition can be improved opticglass and optical element chemical durability, improve the effect of the devitrification resistance of melten glass, therefore can contain arbitrarily, but if surplus contains, then specific refractory power significantly reduces, photoelastic constant becomes big easily.Therefore, the upper limit be preferably 3.0 quality %, more preferably 2.0 quality %, most preferably be 1.0 quality %.Al ₂O ₃Composition can import with raw material form arbitrarily, but preferably with oxide compound (Al ₂O ₃), oxyhydroxide (Al (OH) ₃), fluorochemical (AlF ₃) form import.

P ₂O ₅Therefore can the be improved effect of glass melting of composition can contain arbitrarily, but if surplus contains, and the devitrification resistance of glass remarkable variation easily then is difficult to obtain the opticglass of no devitrification.Therefore, the upper limit be preferably 5.0 quality %, more preferably 1.0 quality %, most preferably do not contain fully.P ₂O ₅Composition can import with raw material form arbitrarily, but preferably with Al (PO ₃) ₃, Ca (PO ₃) ₂, Ba (PO ₃) ₂, BPO ₄, H ₃PO ₄Form import.

The ZnO composition improves glass melting, on the other hand, can obtain reducing the effect of evenly heat exapnsion factor alpha, thereby can contain arbitrarily in the scope of 0～10.0 quality %, owing to have the character that photoelastic constant β is enlarged markedly, thereby, if surplus contains, then be difficult to realize desired characteristic.The preferred scope of the upper limit is 5.0 quality %, less than 2.0 quality % most preferably, and lower limit is preferably 0.1 quality %.The ZnO composition can import with raw material form arbitrarily, but preferably with oxide compound (ZnO) and/or fluorochemical (ZnF ₂) form import.

Lu ₂O ₃Composition and La ₂O ₃, Gd ₂O ₃, Y ₂O ₃Composition is same, can accomplished high refractive index and low dispersive effect, thereby can contain arbitrarily in the scope of 0～5.0 quality %, but because it is the rare mineral resource, thereby preferred surplus contains.Preferred higher limit is 3.0 quality %, does not most preferably contain fully.Lu ₂O ₃Composition can import with raw material form arbitrarily, but preferably with oxide compound (Lu ₂O ₃) import.

TeO ₂The effect of the clarification when composition can obtain promoting glass melting, thereby can contain arbitrarily, but if surplus contains in the scope of 0～3.0 quality %, then to glass painted become significantly, the easy variation of transmitance.Preferred higher limit is 1.5 quality %, does not most preferably contain fully.TeO ₂Composition can import with raw material form arbitrarily, but preferably with oxide compound (TeO ₂) import.

Sb ₂O ₃Composition can obtain the effect as the deaeration material of glass, thereby can contain arbitrarily in the scope of 0～2.0 quality %, but if contain above its upper limit, then be easy to generate during glass melting the over-drastic foaming, may with fusion equipment precious metals such as (particularly) Pt alloying, thereby preferably contain and be no more than its upper limit.Sb ₂O ₃Composition can import with raw material form arbitrarily, but preferably with oxide compound (Sb ₂O ₃, Sb ₂O ₅) or Na ₂H ₂Sb ₂O ₇5H ₂The form of O imports.

The F composition can obtain making Abbe number to become big effect, the effect that photoelastic constant β is reduced, thereby, can contain arbitrarily in the scope of 0～3.0 quality %, but if contain above its upper limit, then the easy step-down of possibility specific refractory power, average coefficient of linear expansion α increase.Preferred higher limit is 2.8 quality %, most preferably be 2.5 quality %.In the importing of above-mentioned various oxide compounds, when importing the raw material form with fluorochemical, the F composition is directed in the glass.

In addition, the content of employed each composition is that the statement of benchmark is to be illustrated in supposition to be decomposed fully when the fusion as the employed oxide compound of the raw material of glass moiety of the present invention, composite salt, metal fluoride etc. and to become under the situation of oxide compound with the oxide compound in this manual, this of each composition generates the quality % of oxide compound with respect to all compositions, under the situation of fluorochemical, represent with respect to the mass percent that generates oxide mass with the actual F atomic mass that contains.

Each transiting metal component such as the V except that Ti, Cr, Mn, Fe, Co, Ni, Cu, Ag and Mo contain separately respectively or compound situation about containing on a small quantity under all carry out painted, specific wavelength to the visible region produces absorption, thereby, preferably be substantially devoid of in the opticglass of the wavelength of use visible region.In addition, for Pb, Th, Cd, Tl, As, Os, each composition of Be, Se, trend in recent years is to control its use as detrimental substance, not only in the manufacturing process of glass, also need the processing on the environmental cure in manufacturing procedure and in the processing after making product, under the situation of paying attention to the influence on the environment, preferably be substantially devoid of.

In the opticglass of aforementioned component 11, by will be as the ZrO of difficult molten component ₂, Ta ₂O ₅, Nb ₂O ₅Total amount and the SiO that forms composition as glass ₂, B ₂O ₃The ratio of total amount be controlled at the ratio (ZrO of quality % ₂+ Ta ₂O ₅+ Nb ₂O ₅)/(SiO ₂+ B ₂O ₃) less than 1.00, can be reduced energy expenditure and do not need to make the glass melting temperature to become the effect of very high temperature.The ratio of above-mentioned quality % was greater than 1.00 o'clock, because Ta ₂O ₅, Nb ₂O ₅Each composition be the rare mineral resource, thereby this ratio is big more, then cost of raw and processed materials is high more, and the content that glass forms composition relatively tails off, not only might glass instabilityization, and owing to the ZrO that makes the photoelastic constant increase ₂, Ta ₂O ₅, Nb ₂O ₅Relative content become big, have the B that makes the effect that average coefficient of linear expansion α reduces ₂O ₃Relative content tail off, thereby might product α * β increases, and produces the aspect of desired opticglass from cheapness and considers, and is not preferred.

In the opticglass of aforementioned component 12,, make rare mineral resource Y by in the composition that can realize the low dispersing characteristic of high refractive index ₂O ₃Composition less than 3.5 quality %, the manufacturing cost that can be reduced, the effect of glass can stablized and make constantly, and by making the ratio (ZnO+Y of quality % ₂O ₃)/La ₂O ₃Greater than 0 and less than 0.5, can stably be formed the effect of the opticglass of realizing desired product α * β, in addition, by quality % sum ZrO ₂+ Nb ₂O ₅Greater than 5.0 quality % and less than 13.0 quality %, can obtain limiting difficult molten component content, suppress energy expenditure, realize the effect of the opticglass of devitrification resistance excellence simultaneously.

In the opticglass of aforementioned component 13, write the scope of the moiety ratio of optimal opticglass in the opticglass of understanding above-mentioned composition 1～12.Specifically, by being formed, glass remains on

SiO ₂For greater than 1.0 quality % and less than 10.0 quality %,

B ₂O ₃Be 15.0～28.0 quality %,

La ₂O ₃Be 28.0～35.0 quality %,

Gd ₂O ₃Be 25.0～35.0 quality %,

ZrO ₂Be 5.0～9.0 quality % and

ZnO be 0.1～less than, 2.0 quality % and

Ta ₂O ₅Be 0.0～6.0 quality % and/or

Nb ₂O ₅Be 0.0～5.0 quality % and/or

Sb ₂O ₃Be 0.0～1.0 quality % and/or

Al ₂O ₃Be 0.0～less than, 1.0 quality %,

Have following advantage: the optical constant that can stably particularly be had specific refractory power (nd) and be 1.78～1.83, Abbe number (ν d) is 44～48 scope, the product α * β of the photoelastic constant β when-30～+ 70 ℃ average coefficient of linear expansion α and wavelength 546.1nm is 90 * 10 ^-12℃ ^-1* nm * cm ^-1* Pa ^-1Following opticglass.As mentioned above, by making moiety and its content is the ratio of specialized range, the use of difficult molten component, rare mineral resource can be suppressed to the high composition of inferior limit and non-environment for use load, just can produce the optical element with low uncertainty, high precision/high meticulous purposes of imaging characteristic under the environment for use.

As form as described in 14～16, the described opticglass of aforementioned component 1～13 is useful as the starting material that are used to make optical elements such as lens, prism, by this optical element being used for photographic camera or pick up camera, projector, can realize high meticulous and high-precision imaging and projection property.

Glass composition of the present invention, its composition represent with quality %, because of rather than directly be expressed as the record of mol%, satisfy the composition of representing with mol% of each composition of existing in the glass composition of each characteristic of the presently claimed invention and probably get following value.

The scope of composition 1 is SiO ₂2.0～25.0mol%, B ₂O ₃The ratio SiO of 25～65mol%, mol% ₂/ B ₂O ₃Greater than 0 and less than 0.7, La ₂O ₃10～30mol%;

The scope of composition 3 is Gd ₂O ₃0～18mol%, Y ₂O ₃0～10mol%, ZrO ₂0～10mol%, Ta ₂O ₅0～10mol%, Nb ₂O ₅0～10mol%, WO ₃0～5mol%;

The scope of composition 4 is GeO ₂0.0～0.1mol%, Yb ₂O ₃0.0～1.0mol%, Ga ₂O ₃0.0～1.0mol%, Bi ₂O ₃0.0～1.0mol%;

The scope of composition 7 is ratio (Ta of mol% ₂O ₅+ Nb ₂O ₅+ WO ₃)/(Gd ₂O ₃+ Y ₂O ₃) greater than 0.03 and less than 1.25;

The scope of composition 8 is to be expressed as Li with Mol% ₂O 0～7.0%, Na ₂O 0～5.0%, K ₂O 0～5.0%, Cs ₂O 0～3.0%, MgO 0～5.0%, CaO 0～5.0%, SrO 0～5.0%, BaO 0～5.0%, TiO ₂0～5.0%, SnO ₂0～3.0%, Al ₂O ₃0～3.0%, P ₂O ₅0～3.0%, ZnO 0～7.0%, Lu ₂O ₃0～2.0%, TeO ₂0～1.0%, Sb ₂O ₃0～1.0%, F 0～10%;

The scope of composition 9 is the not enough 5.0mol% of ZnO;

The scope of composition 10 is Y ₂O ₃Not enough 4.0mol%;

The scope of composition 11 is ratio (ZrO of mol% ₂+ Ta ₂O ₅+ Nb ₂O ₅)/(SiO ₂+ B ₂O ₃) less than 0.8;

The scope of composition 12 is Y ₂O ₃Ratio (the ZnO+Y of not enough 4.0mol%, mol% ₂O ₃)/La ₂O ₃Greater than 0 and less than 1.0, mol% sum ZrO ₂+ Nb ₂O ₅Greater than 5.0% and less than 13.0%;

The scope of composition 13 is SiO ₂3～22mol%, B ₂O ₃27～63mol%, La ₂O ₃10～25mol%, Gd ₂O ₃6～15mol%, ZrO ₂4～10mol%, ZnO0.1～2.0mol%, Ta ₂O ₅0～5.0mol%, Nb ₂O ₅0～3mol%, Sb ₂O ₃0～0.5mol%, Al ₂O ₃0～not enough 1.0mol%.

Embodiment

Then, the present invention is described in more detail, but the present invention is not limited to this example by embodiment.

Be used to not to be vulnerable to imaging characteristic influence that the temperature variation of environment for use causes shown in table 1～table 8, specific refractory power (nd) is more than 1.75, and Abbe number (ν d) is that the low glass of the suitable embodiment (No.1～38) of opticglass that disperses of the high refractive index more than 35 is formed, specific refractory power (nd), Abbe number (ν d),-30～+ 70 ℃ average coefficient of linear expansion α, photoelastic constant β during wavelength 546.1nm, product α * β, the ratio of various composition containing ratios and containing ratio sum.

In addition, the comparative example of known opticglass shown in the table 9 (form and various physics value by the glass of No.A～C).At this, Comparative examples A is that embodiment 6, the comparative example B of TOHKEMY 2005-306732 communique is that embodiment 1, the comparative example C of TOHKEMY 2002-284542 communique is the embodiment 7 of TOHKEMY 2004-161506 communique.Specific refractory power in the table (nd), Abbe number (ν d) are the values of putting down in writing in each communique.

For the opticglass of gained, the photoelastic constant (β) when measuring specific refractory power (nd), Abbe number (ν d) ,-30～+ 70 ℃ average coefficient of linear expansion (α), wavelength 546.1nm as described below.

(1) specific refractory power (nd) and Abbe number (ν d)

Being made as-25 ℃/hour and the opticglass that obtains for the slow speed of cooling measures.

(2)-30 ℃ average coefficient of linear expansion (α)～+ 70

Can standard JOGIS16-based on Japanese optics nitre industry ²⁰⁰³The method that (near the measuring method of the average coefficient of linear expansion the normal temperature of opticglass) put down in writing is measured.Use the sample of long 50mm, diameter 4mm as test film.

(3) the photoelastic constant β during wavelength 546.1nm

Photoelastic constant (β) is that to make specimen shape be relatively grind the diameter 25mm, the thick 8mm that obtain discoideus, and prescribed direction is applied compression load, is determined at the path difference that the center of glass produces, and tries to achieve by δ=β dF relational expression.Use ultrahigh pressure mercury lamp 546.1nm measure light source.In above-mentioned formula, the thickness that path difference is designated as δ (nm), glass is designated as d (cm), stress is designated as F (Pa).

Table 1

Quality %	1	2	3	4	5
						SiO 2	2.62	2.60	2.60	2.60	2.60
B 2O 3	31.20	31.22	31.22	29.22	30.21
						Al 2O 3
P 2O 5
						Y 2O 3	11.70	10.70	10.70	10.70	10.75
La 2O 3	44.31	45.31	44.31	45.31	45.19
						Gd 2O 3
Yb 2O 3
						Lu 2O 3			1.00
TiO 2
						ZrO 2	6.60	6.60	6.60	6.50	6.60
SnO 2
						TeO 2				0.10
Nb 2O 5	1.62	1.62	1.62	1.62	2.71
						Ta 2O 5
WO 3
						ZnO	0.90	0.90	0.90	0.90	0.90
MgO
						CaO
SrO	1.00	1.00	1.00	1.00	1.00
						BaO
Li 2O
						Na 2O				1.00
K 2O
						Cs 2O
Sb 2O 3	0.05	0.05	0.05	0.05	0.04
						F				1.00
Amount to	100.00	100.00	100.00	100.00	100.00
						α	62	62	62	64	62
β	1.44	1.43	1.43	1.40	1.42
						α×β	89.28	88.66	88.66	89.60	88.04
nd	1.772	1.773	1.773	1.773	1.780
						νd	49.6	49.6	49.6	50.0	48.5
SiO 2/B 2O 3	0.084	0.083	0.083	0.089	0.086
						(Ta 2O 5+Nb 2O 5+WO 3) /(Gd 2O 3+Y 2O 3)	0.138	0.151	0.151	0.151	0.252
(ZrO 2+Ta 2O 5+Nb 2O 5) /(SiO 2+B 2O 3)	0.243	0.243	0.243	0.255	0.284
						(ZnO+Y 2O 3)/La 2O 3	0.284	0.256	0.262	0.256	0.258
ZrO 2+Nb 2O 5	8.22	8.22	8.22	8.12	9.31

Table 2

Quality %	6	7	8	9	10
						SiO 2	2.00	2.60	2.60	2.32	2.60
B 2O 3	29.00	29.20	29.20	27.87	28.20
						Al 2O 3
P 2O 5	0.54
						Y 2O 3		8.80	10.80		10.80
La 2O 3	29.49	47.06	45.06	39.02	45.06
						Gd 2O 3	26.97			18.89
Yb 2O 3
						Lu 2O 3
TiO 2		0.50
						ZrO 2	6.71	6.60	6.60	6.66	6.60
SnO 2
						TeO 2	0.05			0.04
Nb 2O 5	2.96	3.30	3.80	3.75	3.80
						Ta 2O 5	2.28
WO 3					0.50
						ZnO		0.90	0.90	0.95	0.90
MgO
						CaO
SrO		1.00	1.00		0.50
						BaO
Li 2O				0.50
						Na 2O
K 2O					1.00
						Cs 2O
Sb 2O 3		0.04	0.04		0.04
						F
Amount to	100.00	100.00	100.00	100.00	100.00
						α	60	61	61	61	61
β	1.46	1.38	1.40	1.42	1.40
						α×β	87.60	84.18	85.40	86.62	85.40
nd	1.783	1.788	1.788	1.788	1.789
						νd	47.3	47.4	47.4	48.1	47.3
SiO 2/B 2O 3	0.069	0.089	0.089	0.083	0.092
						(Ta 2O 5+Nb 2O 5+WO 3) /(Gd 2O 3+Y 2O 3)	0.194	0.375	0.352	0.199	0.398
(ZrO 2+Ta 2O 5+Nb 2O 5) /(SiO 2+B 2O 3)	0.385	0.311	0.327	0.345	0.338
						(ZnO+Y 2O 3)/La 2O 3	0	0.206	0.260	0.024	0.260
ZrO 2+Nb 2O 5	9.67	9.90	10.40	10.41	10.40

Table 3

Quality %	11	12	13	14	15
						SiO 2	2.60	2.30	2.00	2.00	2.00
B 2O 3	29.00	27.87	26.54	26.54	26.54
						Al 2O 3			0.10
P 2O 5
						Y 2O 3	12.86	5.40
La 2O 3	43.00	38.76	32.49	32.49	32.49
						Gd 2O 3		13.50	26.98	26.97	26.97
Yb 2O 3
						Lu 2O 3
TiO 2
						ZrO 2	6.60	6.66	7.29	6.71	6.71
SnO 2
						TeO 2
Nb 2O 5	3.80	3.38	3.56	2.96	3.56
						Ta 2O 5		1.14		0.28
WO 3
						ZnO	1.10	0.45	1.00	2.00	1.00
MgO		0.50
						CaO
SrO	1.00
						BaO					0.68
Li 2O
						Na 2O
K 2O
						Cs 2O
Sb 2O 3	0.04	0.04	0.04	0.05	0.05
						F
Amount to	100.00	100.00	100.00	100.00	100.00
						α	61	60	61	61	63
β	1.43	1.43	1.43	1.43	1.40
						α×β	87.23	85.80	87.23	87.23	88.20
nd	1.789	1.796	1.799	1.800	1.801
						νd	47.3	47.0	46.3	47.0	46.7
SiO 2/B 2O 3	0.090	0.083	0.075	0.075	0.075
						(Ta 2O 5+Nb 2O 5+WO 3) /(Gd 2O 3+Y 2O 3)	0.295	0.239	0.132	0.120	0.132
(ZrO 2+Ta 2O 5+Nb 2O 5) /(SiO 2+B 2O 3)	0.329	0.371	0.380	0.349	0.360
						(ZnO+Y 2O 3)/La 2O 3	0.325	0.151	0.031	0.062	0.031
ZrO 2+Nb 2O 5	10.40	10.04	10.85	9.67	10.27

Table 4

Quality %	16	17	18	19	20
						SiO 2	2.15	2.00	2.04	2.00	7.49
B 2O 3	26.54	26.54	26.54	26.54	17.71
						Al 2O 3
P 2O 5
						Y 2O 3				5.00
La 2O 3	32.49	32.45	32.99	37.48	29.81
						Gd 2O 3	26.98	27.00	26.97	15.98	31.06
Yb 2O 3
						Lu 2O 3
TiO 2
						ZrO 2	6.71	6.72	6.72	6.71	7.04
SnO 2					0.60
						TeO 2
Nb 2O 5	4.09	2.96	3.69	2.96
						Ta 2O 5		2.28		2.28	2.25
WO 3
						ZnO	1.00		1.00		1.00
MgO
						CaO
SrO
						BaO					3.00
Li 2O
						Na 2O
K 2O
						Cs 2O				1.00
Sb 2O 3	0.04	0.05	0.05	0.05	0.04
						F
Amount to	100.00	100.00	100.00	100.00	100.00
						α	59	60	61	61	65
β	1.48	1.42	1.41	1.41	1.30
						α×β	87.32	85.20	86.01	86.01	84.50
nd	1.803	1.804	1.804	1.805	1.806
						νd	45.9	46.6	46.6	46.5	47.4
SiO 2/B 2O 3	0.081	0.075	0.077	0.075	0.423
						(Ta 2O 5+Nb 2O 5+WO 3) /(Gd 2O 3+Y 2O 3)	0.152	0.194	0.137	0.250	0.072
(ZrO 2+Ta 2O 5+Nb 2O 5) /(SiO 2+B 2O 3)	0.376	0.419	0.364	0.419	0.369
						(ZnO+Y 2O 3)/La 2O 3	0.031	0	0.030	0.133	0.034
ZrO 2+Nb 2O 5	10.80	9.68	10.41	9.67	7.04

Table 5

Quality %	21	22	23	24	25
						SiO 2	7.49	7.51	7.52	7.52	7.50
B 2O 3	17.71	18.33	18.02	17.94	17.76
						Al 2O 3
P 2O 5
						Y 2O 3	3.00
La 2O 3	29.81	32.41	31.75	31.34	29.71
						Gd 2O 3	31.06	31.66	31.52	31.45	31.08
Yb 2O 3
						Lu 2O 3
TiO 2
						ZrO 2	7.04	7.06	7.07	7.07	7.05
SnO 2					0.60
						TeO 2
Nb 2O 5		1.98	1.32	0.99
						Ta 2O 5	2.25		1.75	2.63	5.25
WO 3
						ZnO	1.00	1.00	1.00	1.01	1.00
MgO
						CaO	0.60
SrO
						BaO
Li 2O
						Na 2O
K 2O
						Cs 2O
Sb 2O 3	0.04	0.05	0.05	0.05	0.05
						F
Amount to	100.00	100.00	100.00	100.00	100.00
						α	64	64	63	64	63
β	1.36	1.29	1.32	1.26	1.37
						α×β	87.04	82.56	83.16	80.64	86.31
nd	1.812	1.814	1.816	1.816	1.816
						νd	47.4	46.6	46.6	46.6	46.6
SiO 2/B 2O 3	0.423	0.410	0.417	0.419	0.422
						(Ta 2O 5+Nb 2O 5+WO 3) /(Gd 2O 3+Y 2O 3)	0.066	0.063	0.097	0.115	0.169
(ZrO 2+Ta 2O 5+Nb 2O 5) /(SiO 2+B 2O 3)	0.369	0.350	0.397	0.420	0.487
						(ZnO+Y 2O 3)/La 2O 3	0.134	0.031	0.031	0.032	0.034
ZrO 2+Nb 2O 5	7.04	9.04	8.39	8.06	7.05

Table 6

Quality %	26	27	28	29	30
						SiO 2	7.49	2.43	5.17	1.94	2.38
B 2O 3	17.96	24.96	20.66	24.64	24.02
						Al 2O 3
P 2O 5
						Y 2O 3		1.50			1.50
La 2O 3	31.81	38.46	37.63	41.88	42.90
						Gd 2O 3	31.05	17.57	21.31	16.34	12.26
Yb 2O 3
						Lu 2O 3
TiO 2
						ZrO 2	7.04	6.63	6.80	6.50	5.57
SnO 2
						TeO 2				0.100
Nb 2O 5	3.00	4.98	3.63	5.55	7.40
						Ta 2O 5		2.92	4.24		2.92
WO 3	0.60			3.00
						ZnO	1.00	0.50	0.51		1.00
MgO
						CaO
SrO
						BaO
Li 2O
						Na 2O
K 2O
						Cs 2O
Sb 2O 3	0.05	0.05	0.05	0.05	0.05
						F
Amount to	100.00	100.00	100.00	100.00	100.00
						α	63	62	63	64	62
β	1.34	1.36	1.29	1.34	1.31
						α×β	84.42	84.32	81.27	85.76	81.22
nd	1.819	1.819	1.825	1.826	1.834
						νd	45.5	44.7	44.7	43.4	42.6
SiO 2/B 2O 3	0.417	0.097	0.250	0.079	0.099
						(Ta 2O 5+Nb 2O 5+WO 3) /(Gd 2O 3+Y 2O 3)	0.116	0.414	0.369	0.523	0.750
(ZrO 2+Ta 2O 5+Nb 2O 5) /(SiO 2+B 2O 3)	0.394	0.530	0.568	0.453	0.602
						(ZnO+Y 2O 3)/La 2O 3	0.031	0.052	0.014	0.000	0.058
ZrO 2+Nb 2O 5	10.04	11.61	10.43	12.05	12.97

Table 7

Quality %	31	32	33	34	35
						SiO 2	2.82	7.39	4.61	6.43	5.89
B 2O 3	23.38	14.96	17.67	11.67	12.46
						Al 2O 3
P 2O 5
						Y 2O 3	3.00			1.33
La 2O 3	43.92	39.99	41.96	42.11	40.00
						Gd 2O 3	8.17	15.38	12.08	13.54	15.38
Yb 2O 3			1.00
						Lu 2O 3
TiO 2			0.50		0.30
						ZrO 2	6.54	5.99	6.27	6.00	5.99
SnO 2		0.50		0.33
						TeO 2
Nb 2O 5	6.27	1.00	3.14	0.50	1.00
						Ta 2O 5	5.85	14.69	12.27	15.82	17.38
WO 3
						ZnO				1.90	1.00
MgO
						CaO
SrO				0.30
						BaO
Li 2O
						Na 2O			0.50
K 2O					0.50
						Cs 2O
Sb 2O 3	0.05	0.10		0.07	0.10
						F
Amount to	100.00	100.00	100.00	100.00	100.00
						α	62	62	64	65	67
β	1.31	1.38	1.31	1.31	1.33
						α×β	81.22	85.56	83.84	85.15	89.11
nd	1.835	1.847	1.859	1.878	1.881
						νd	42.7	42.7	41.8	41.2	40.7
SiO 2/B 2O 3	0.121	0.494	0.261	0.551	0.473
						(Ta 2O 5+Nb 2O 5+WO 3) /(Gd 2O 3+Y 2O 3)	1.085	1.020	1.276	1.098	1.195
(ZrO 2+Ta 2O 5+Nb 2O 5) /(SiO 2+B 2O 3)	0.712	0.970	0.973	1.233	1.328
						(ZnO+Y 2O 3)/La 2O 3	0.068	0.000	0.000	0.077	0.025
ZrO 2+Nb 2O 5	12.81	6.99	9.41	6.50	6.99

Table 8

Quality %	36	37	38
				SiO 2	6.39	5.92	6.42
B 2O 3	11.96	12.50	11.65
				Al 2O 3
P 2O 5
				Y 2O 3			1.33
La 2O 3	39.99	40.47	42.02
				Gd 2O 3	15.39	15.46	13.51
Yb 2O 3
				Lu 2O 3
TiO 2		0.25
				ZrO 2	5.99	6.03	5.99
SnO 2	0.50		0.50
				TeO 2
Nb 2O 5	1.00	1.00	0.50
				Ta 2O 5	18.68	17.62	15.79
WO 3			2.19
				ZnO		0.65
MgO
				CaO
SrO
				BaO
Li 2O
				Na 2O
K 2O
				Cs 2O
Sb 2O 3	0.10	0.10	0.10
				F
Amount to	100.00	100.00	100.00
				α	66	68	67
β	1.30	1.32	1.34
				α×β	85.80	89.76	89.78
nd	1.883	1.883	1.883
				νd	40.8	40.8	40.7
SiO 2/B 2O 3	0.534	0.474	0.551
				(Ta 2O 5+Nb 2O 5+WO 3) /(Gd 2O 3+Y 2O 3)	1.279	1.204	1.245
(ZrO 2+Ta 2O 5+Nb 2O 5) /(SiO 2+B 2O 3)	1.399	1.338	1.233
				(ZnO+Y 2O 3)/La 2O 3	0	0.016	0.032
ZrO 2+Nb 2O 5	6.99	7.03	6.49

Table 9

Quality %	Comparative examples A	Comparative example B	Comparative example C
				SiO 2	6.70	1.00	6.00
B 2O 3	10.80	24.00	34.50
				Al 2O 3
P 2O 5
				Y 2O 3	3.80	2.18
La 2O 3	41.80	40.68	30.00
				Gd 2O 3	9.60	12.68
Yb 2O 3
				Lu 2O 3
TiO 2
				ZrO 2	5.20	6.00	5.00
SnO 2
				TeO 2
Nb 2O 5	1.30	7.75
				Ta 2O 5	15.90
WO 3
				ZnO	4.50	5.75	22.00
MgO
				CaO			2.00
SrO
				BaO			0.50
Li 2O	0.20
				Na 2O
K 2O
				Cs 2O
Sb 2O 3	0.20
				F
Amount to	100.00	100.04	100.00
				α	71	67	51
β	1.28	1.50	2.55
				α×β	90.88	100.50	130.05
nd	1.88	1.834	1.783
				νd	40.9	42.7	47.7
SiO 2/B 2O 3	0.620	0.042	0.174
				(Ta 2O 5+Nb 2O 5+WO 3) /(Gd 2O 3+Y 2O 3)	1.284	0.522
(ZrO 2+Ta 2O 5+Nb 2O 5) /(SiO 2+B 2O 3)	1.280	0.550	0.123
				(ZnO+Y 2O 3)/La 2O 3	0.199	0.195	0.733
ZrO 2+Nb 2O 5	6.50	13.75	5.00

The glass of table 1～8 embodiments of the invention of being put down in writing is following acquisitions, promptly, all use corresponding respectively oxide compound, oxyhydroxide, carbonate, nitrate, fluorochemical, oxyhydroxide, common opticglass raw material such as metaphosphoric acid compound is as the raw material of each composition, ratio with regulation is carried out weighing, after the mixing, put in the platinum crucible, the fusion difficulty of forming according to glass in electric furnace in 1200～1400 ℃ temperature range fusion 3～4 hours, after the stirring, cool to proper temperature, be cast to then in mould etc., slowly cool off, obtain the glass of the embodiment of the invention thus.

Shown in table 1～8, all can realize desired optical constant, product α * β as can be known in the preferred embodiments of the present invention.On the other hand, in the comparative example shown in the table 9, Comparative examples A can realize less α * β, but if compare with the approaching embodiment 36～34 of optical constant, then the ratio SiO of quality % ₂/ B ₂O ₃Than greater than 0.6, therefore, that average coefficient of linear expansion α becomes is big, product α * β is greater than 90 * 10 ^-12℃ ^-1* nm * cm ^-1* Pa ^-1In addition, in comparative example B, if compare with the approaching embodiment 30～32 of optical constant, then owing to contain ZnO in a large number, so photoelastic constant β becomes big, and product α * β is greater than 100 * 10 ^-12℃ ^-1* nm * cm ^-1* Pa ^-1In addition, because SiO ₂Content is few, the ratio SiO of quality % ₂/ B ₂O ₃Than less than 0.05, so the devitrification resistance of glass is insufficient, when watering cast glass, almost produced crystallization in glass surface integral body.In addition, in comparative example C, the content of ZnO significantly becomes ratio (ZnO+Y many, quality % ₂O ₃)/La ₂O ₃Being 0.733, is big value, thereby photoelastic constant β increases, product α * β is greater than 130 * 10 ^-12℃ ^-1* nm * cm ^-1* Pa ^-1

In addition, the glass of the embodiment that his-and-hers watches 1～8 are put down in writing carries out cold working or hot repressing system (reheat press) processing, stablizes with found that problems such as can not producing devitrification and is processed into various lens, prism shape.

Lens, the prism that makes as described above is contained on photographic camera or pick up camera, the projector, confirm imaging characteristic, when high temperature (about 50～70 ℃) is worked, also can reproduce even found that the desired imaging characteristic of optical design that utilization is carried out in the optical constant that room temperature obtains.

More than, for illustrative purposes, the present invention is had been described in detail, but present embodiment only is to be used for illustration eventually, be appreciated that those skilled in the art can carry out more changes and finish in not breaking away from thought of the present invention and scope.

Utilizability on the industry

According to the present invention, can provide imaging characteristic impact that the variations in temperature that is not vulnerable to environment for use causes, refractive index (nd) is 1.75 or more and Abbe number (ν d) is that high index of refraction 35 or more is hanged down dispersion optical glass, use this optical glass, can stably make lens, the prism of image projection (regeneration) machines such as the shooting machine such as high-precision camera or video camera and projecting apparatus.

Claims (16)

1. an opticglass is characterized in that, the product α * β of the photoelastic constant β when-30～+ 70 ℃ average coefficient of linear expansion α of this opticglass and wavelength 546.1nm is 130 * 10 ^-12℃ ^-1* nm * cm ^-1* Pa ^-1Below, wherein, be benchmark with the oxide compound, contain SiO greater than 1.0 quality % and less than 12.0 quality % ₂, contain the B of 8.0～35.0 quality % ₂O ₃, and the ratio SiO of quality % ₂/ B ₂O ₃Greater than 0 and less than 0.6, contain the La of 25.0～50.0 quality % ₂O ₃

2. opticglass according to claim 1 is characterized in that, the optical constant that it has, and specific refractory power (nd) is 1.75～2.00, Abbe number (vd) is 35～55 scope.

3. opticglass according to claim 1 and 2 is characterized in that, is benchmark with the oxide compound, also contains 0.0～40.0 quality %Gd ₂O ₃, 0.0～15.0 quality %Y ₂O ₃, 0.0～15.0 quality %ZrO ₂, 0.0～25.0 quality %Ta ₂O ₅, 0.0～18.0 quality %Nb ₂O ₅, 0.0～10.0 quality %WO ₃

4. according to each described opticglass in the claim 1～3, it is characterized in that, is benchmark with the oxide compound, contains

0～0.1 quality %GeO ₂And/or

0～1.0 quality %Yb ₂O ₃And/or

0～1.0 quality %Ga ₂O ₃And/or

0～1.0 quality %Bi ₂O ₃,

Do not contain lead compound and As such as PbO ₂O ₃Deng arsenic compound.

5. according to each described opticglass in the claim 1～4, it is characterized in that the product α * β of the photoelastic constant β when-30～+ 70 ℃ average coefficient of linear expansion α and wavelength 546.1nm is 100 * 10 ^-12℃ ^-1* nm * cm ^-1* Pa ^-1Below.

6. according to each described opticglass in the claim 1～5, it is characterized in that the product α * β of the photoelastic constant β when-30～+ 70 ℃ average coefficient of linear expansion α and wavelength 546.1nm is 90 * 10 ^-12℃ ^-1* nm * cm ^-1* Pa ^-1Below.

7. according to each described opticglass in the claim 1～6, it is characterized in that, is benchmark with the oxide compound, the ratio (Ta of quality % ₂O ₅+ Nb ₂O ₅+ WO ₃)/(Gd ₂O ₃+ Y ₂O ₃) greater than 0.05 and less than 1.30.

8. according to each described opticglass in the claim 1～7, it is characterized in that, represent, contain with quality % based on oxide compound

0～5.0%Li ₂O and/or

0～5.0%Na ₂O and/or

0～5.0%K ₂O and/or

0～5.0%Cs ₂O and/or

0～5.0%MgO and/or

0～5.0%CaO and/or

0～5.0%SrO and/or

0～5.0%BaO and/or

0～3.0%TiO ₂And/or

0～3.0%SnO ₂And/or

0～3.0%Al ₂O ₃And/or

0～5.0%P ₂O ₅And/or

0～10.0%ZnO and/or

0～5.0%Lu ₂O ₃And/or

0～3.0%TeO ₂And/or

0～2.0%Sb ₂O ₃And/or

0～3.0％F。

9. according to each described opticglass in the claim 1～8, it is characterized in that, is benchmark with the oxide compound, contains the ZnO of less than 2.0 quality %.

10. according to each described opticglass in the claim 1～9, it is characterized in that, is benchmark with the oxide compound, contains the Y of less than 3.5 quality % ₂O ₃

11., it is characterized in that according to each described opticglass in the claim 1～10, with the oxide compound benchmark, the ratio (ZrO of quality % ₂+ Ta ₂O ₅+ Nb ₂O ₅)/(SiO ₂+ B ₂O ₃) less than 1.00.

12., it is characterized in that according to each described opticglass in the claim 1～11, be benchmark with the oxide compound, contain the Y of less than 3.5 quality % ₂O ₃, the ratio (ZnO+Y of quality % ₂O ₃)/La ₂O ₃Greater than 0 and less than 0.5, quality % sum ZrO ₂+ Nb ₂O ₅Greater than 5.0% and less than 13.0%.

13. an opticglass is characterized in that, is benchmark with the oxide compound, this glass contains

SiO greater than 1.0 quality % and less than 10.0 quality % ₂,

15.0～28.0 quality %B ₂O ₃,

28.0～35.0 quality %La ₂O ₃,

25.0～35.0 quality %Gd ₂O ₃,

5.0～9.0 quality %ZrO ₂With

The ZnO of 1～less than, 2.0 quality % and

0～6.0 quality %Ta ₂O ₅And/or

0～5.0 quality %Nb ₂O ₅And/or

0～1.0 quality %Sb ₂O ₃And/or

The Al of 0～less than, 1.0 quality % ₂O ₃,

And, ZrO ₂+ Nb ₂O ₅Total greater than 5.0 quality % and less than 13.0 quality %, the optical constant that this opticglass has that specific refractory power (nd) is 1.78～1.83, Abbe number (vd) is 44～48 scope, the product α * β of the photoelastic constant β when-30～+ 70 ℃ average coefficient of linear expansion α and wavelength 546.1nm is 90 * 10 ^-12℃ ^-1* nm * cm ^-1* Pa ^-1Below.

14. optical element such as lens, prism, its with the glass of claim 1～13 as starting material.

15. optical element such as lens, prism, it carries out hot repressing system by the glass to claim 1～14 and is processed into.

16. optical apparatus such as photographic camera or pick up camera, projector, it uses optical element and the optical substrate material made from the glass of claim 1～15.