CN1729149A - UV photosensitive melted glasses - Google Patents

Abstract

The present invention relates generally to UV (ultraviolet) photosensitive bulk glass, and particularly to batch meltable alkali boro-alumino-silicate and germanosilicate glasses. The photosensitive bulk glass of the invention exhibits photosensitivity to UV wavelengths below 300 nm. The photosensitivity of the alkali boro-alumino-silicate and germanosilicate bulk glasses to UV wavelengths below 300 nm provide for the making of refractive index patterns in the glass. With a radiation source below 300 nm, such a laser, refractive index patterns are formed in the glass. The inventive photosensitive optical refractive index pattern forming bulk glass allows for the formation of patterns in glass and devices which utilize such patterned glass.

Description

UV photosensitive melted glasses

The cross-reference related application

The application put on record on March 15th, 2002, license to people's such as Borrelli U.S. Patent Application Serial 10/099,088 extendible portion, and being entitled as " UV photosensitive melted glasses " patent is to apply for June 5 calendar year 2001, license to people's such as Borrelli U.S. Patent Application Serial 09/874,342 extendible portion, and the patent that is entitled as " UV photosensitive fusion silicic acid germanite glass " requires in the right of priority of the U.S. Provisional Patent Application series number 60/221,811 of application on July 31st, 2000.The invention of these patent applications is to authorize trustee of the present invention, and the content of these patent applications quotes in full at this.

Invention field

This invention relates generally to photosensitive glass piece (bulk glass), specifically melting basic metal boron-aluminium-silicate and silicic acid germanite glass.

Background of invention

Optical transmission system comprises that opticfiber communication cable has become the high speed of making us attracting to carry the novel field of the sound and data.When the optical communication system performance continued to improve, the pressure multiplication of optical communication industry all departments was made every effort to reduce and is built and the expense of safeguarding that optical-fiber network is relevant.

Optical communication system often requires various types of optical filters.For example, diffraction filter plays separation (demultiplexing) effect of each channel in wavelength-division multiplex (WDM) optical system.In addition, these diffraction filter can be used for the negative effect (ill-effect) of compensation of dispersion, and it comprises chromatic dispersion (CD) and polarization mode dispersion (PMD).

One type of the diffraction optics wave filter is Bragg grating, and Bragg grating is the interference light device.It has various uses, comprises wavelength-division multiplex/demultiplexing and dispersion compensation.Bragg grating can be used for reflecting all light that satisfies Prague phase-matching condition, and the light of all other wavelength of transmission.

A useful technology that forms Bragg grating is exactly specific refractory power and the change of refractive cycle that optionally changes material.The selectivity of this specific refractory power changes that to can be used for making refractive index cycle be the fixed Bragg grating, and the chirped grating that becomes with transmission range of refractive index cycle.

We need is to have photosensitively, and can overcome the batch of material of the fusible glass of some shortcoming of simple glass material.

Summary of the invention

The present invention relates to photosensitive glass.According to an embodiment of the invention, fusile photosensitive glass hydrogen richness is greater than 10 ¹⁷H ₂Molecule/cm ³The variations in refractive index of glass exposure part is measured as 10 at wavelength 633nm place ^-4(Δ n＞10 ^-4); And described glass has photosensitivity to wavelength less than the light of 300nm.

According to another embodiment of the present invention, initial glass is photosensitive basic metal boron (alkali boro)-aluminium-silicate glass, and this glass becomes photosensitive glass after loading hydrogen.In one embodiment of the present invention, this to the light activated glass of wavelength＜300nm, it consists of: 40-80 mole %SiO ₂, 2-15 mole %GeO ₂, 10-36 mole %B ₂O ₃, 1-6 mole %Al ₂O ₃With 2-10 mole %R ₂O, wherein to be the glass of photosensitivity in less than 300nm light at wavelength, R is selected from basic metal.In another embodiment of the present invention, glass is formed and is comprised about 25 weight %-45 weight %SiO ₂, about 3 weight %-22 weight %GeO ₂, about 7 weight %-28 weight %B ₂O ₃, the Al of about 6 weight %-22 weight % ₂O ₃, about 6 weight %-25 weight %R ₂O, wherein R is the F of basic metal and about 3 weight %-11 weight %, described glass is photosensitivity to wavelength less than 300nm.

Another embodiment of the present invention comprises the photosensitive glass piece that is loaded with molecular hydrogen.Described photosensitive glass piece is that fusing point is no more than basic metal boron-alumina silicate glass of 1650 ℃.Preferred glass batch materials is formed and is comprised: be not more than 85 moles of %SiO ₂, be not less than 10 moles of %B ₂O ₃, be not less than 2 moles of %GeO ₂And basic metal and aluminum oxide resultant＜20 mole %Al ₂O ₃+ R ₂O.The amount that this glass can load molecular hydrogen is at least 10 ¹⁸H ₂Molecule/cm ³

Another embodiment of the present invention comprises the photosensitive silicic acid germanite glass of melting material, its hydrogen richness＜10 ¹⁷H ₂/ cm ³In one embodiment, described glass has photosensitivity to wavelength less than the light of 300nm, and it consists of: 40-80 mole %SiO ₂, 2-15 mole %GeO ₂, 10-36 mole %B ₂O ₃, 1-6 mole %Al ₂O ₃With 2-10 mole %R ₂O, wherein R is selected from glass is photosensitivity less than 300nm to wavelength basic metal.In another embodiment, glass ingredient comprises about 25 weight %-45 weight %SiO ₂, about 3 weight %-22 weight %GeO ₂, about 7 weight %-28 weight %B ₂O ₃, the Al of about 6 weight %-22 weight % ₂O ₃, about 6 weight %-25 weight %R ₂O, wherein R is the F of basic metal and about 3 weight %-11 weight %, described glass is photosensitivity to wavelength less than 300nm.

Another embodiment of the present invention comprises the method for making refractive index pattern.Described method comprises provides the photosensitive glass piece, it has the photoabsorption of wavelength 300nm less than 20dB/cm, the irradiation source of wavelength less than 300nm is provided, be lower than at wavelength under the photoirradiation of 300nm and form pattern, and described photosensitive glass piece exposed into described pattern and form the modulated refractive index pattern of described glass block.

Another embodiment of the present invention comprises that making can carry molecular hydrogen photosensitive glass optical device preform.Preferred methods comprises the preform of making refractive index pattern of melten glass.Described method comprises the germanium oxide silica glass powdery batch of material of the transition metal that the 1ppm that contains heavy metal amount≤heavy metal weight is provided.This method comprises the 1ppm of the heavy metal amount≤heavy metal weight of fusing, comprise that also silicon oxide powdery batch of material is melt into the homogeneous glass melt, glass melt is cooled at the glass block of wavelength 300nm photoabsorption less than the transmission UV-light of 20dB/cm, and this glass block is made the preform of the optical device that can form refractive index pattern again.

Another embodiment of the present invention comprises photosensitive glass refractive index pattern preform, is used for ultraviolet ray and generates refractive index pattern.Preform is used for ultraviolet ray and generates index of refraction diagram.Described preform is made less than basic metal boron-aluminium-silicate glass of 20dB/cm by the 300nm photoabsorption.Described preform glass has UV light can induce refraction index modulation, and its Δ n level is greater than 10 ^-5, molecular hydrogen content at least 10 ¹⁸H ₂Molecule/cm ³

Brief Description Of Drawings

The present invention can know understanding by following detailed description together with accompanying drawing.It is emphasized that various features need not to draw in proportion.In fact, for the purpose of clear discussion, dimension of picture can arbitrarily amplify or dwindle.

Fig. 1 is (200-300nm) graph of a relation of absorbancy of the present invention/nm-UV wavelength (nm);

Fig. 2 a is photoinduction refraction index modulation of the present invention [Δ n (x10 ^-4)]-UV time shutter (branch) graph of a relation;

Fig. 2 b is photoinduction refraction index modulation [Δ n (x10 ^-4)]-UV exposure flux (mJ/cm ²) graph of a relation;

Fig. 3 is photosensitive thermostability figure, the graph of a relation of the diffraction efficiency of photoinduction variations in refractive index-400 ℃ heat-up time in the glass block;

Fig. 4 is the graph of a relation of photoinduction specific refractory power of the present invention [Δ n]-OH concentration, and Fig. 4 illustration is absorbancy-wave number (cm ^-1) graph of a relation, represent (dotted line) back (solid line) before 90 minutes UV exposure, irradiation is 20mJ/cm ²OH stretching vibration and absorbancy during/pulse;

Fig. 5 is absorbancy-UV wavelength relationship figure, presses 90 minutes UV exposure preceding (dotted line) backs (solid line) of Fig. 4, and irradiation dose is 20mJ/cm ²The condition of/pulse;

Fig. 6 is the graph of a relation that forms the wavelength (1545nm-1559nm) of refractive index pattern grating in intensity (dBm)-glass block; Fig. 6 illustration is represented UV irradiation geometric condition and reflectivity and transmitance measurement;

What Fig. 7 illustrated is the refractive index pattern grating of Fig. 6, and Fig. 7 a is the cross section of refractive index pattern grating in the glass block;

Fig. 8 illustrates a kind of method of the present invention;

Fig. 9 illustrates a kind of method of the present invention;

Figure 10 is the typical glass component table that embodiment of the present invention adopts

Describe in detail

In describing in detail below, for the purpose of explaining rather than limiting, disclose the enforcement of specific detail Mode is for everybody provides the present invention to be well understood. Yet to those skilled in the art this Be apparent, namely learnt advantage of the present invention, departing under the disclosed specified conditions of this patent, The present invention also can adopt other embodiment. And the explanation of known device, method and material can ignore, Also be unlikely to indigestion the present invention.

To point out that also the variations in refractive index (Δ n) of quoting records at the 633nm place here. At many Close down, this point specializes. Yet, if do not specialize under the individual cases, should be appreciated that Variations in refractive index is to record at the 633nm place.

Briefly, the present invention relates to fusible photosensitive glass material. According to one embodiment of the present invention, The molecular hydrogen content of fusible photosensitive glass material is greater than 10¹⁷H ₂Molecule/cm³ When by wavelength less than 300nm Irradiation the time, the variations in refractive index of the illuminated part of described photosensitive glass material is less than 10^-4 (Δn＜10 ^{- 4}) (recording at the 633nm place). Usefully, by selecting glass material by the irradiation of a certain wave-length coverage, And glass material is light sensitivity in this wave-length coverage, thereby forms grating and other in glass material Member. Glass can be the silicic acid germanite glass. The silicic acid germanite glass generally contains the GeO of at least 2 % by weight₂, and the SiO of at least 20 % by weight₂ In illustrated embodiment of the present invention, GeO of the present invention₂ Content is at least 6 % by weight.

According to an embodiment of the present invention, this photosensitive glass to wavelength＜300nm, it consists of: 80 % by mole of SiO of 40-₂, 2-15 % by mole of GeO₂, 10-36 % by mole of B₂O ₃, 1-6 % by mole of Al₂O ₃With 2-10 % by mole of R₂O, wherein R is alkali metal, described glass presents light sensitivity after carrying hydrogen. Preferred glass ingredient Comprise 42-73 % by mole of SiO₂, 2-15 % by mole of GeO₂, 25-36 % by mole of B₂O ₃, 2-6 % by mole of Al₂O ₃With 2-6 % by mole of R₂O. Described glass comprises 42-67 % by mole of SiO₂, 2-15 % by mole of GeO₂, 25-36 % by mole of B₂O ₃, 2-6 % by mole of Al₂O ₃With 2-6 % by mole of R₂O. Described R₂O is at least a choosing preferably Alkali-metal oxide from Na, Li and K. In one embodiment, R is Na. Real at another Execute in the mode, R is Li. In also having an embodiment, R is K. And, embodiment of the present invention In, R comprises the mixture of Na, Li and K. The mol ratio of alkali metal/aluminium oxide is better in the described glass Between about 1 ± 0.5. Described glass is substantially free of the oxonium ion of non-bridging bond, and this class ion will be from glass Reduce in the glass component and remove.

The present invention also comprises the photosensitive glass piece that can carry molecular hydrogen. Described photosensitive glass piece is fusing point≤1650 ℃ Alkali metal boron-aluminium-silicate glass. Preferred glass batch materials component comprises :≤85 % by mole of SiO₂, 〉=10 % by mole of B₂O ₃, 〉=2 % by mole of GeO₂And alkali metal and aluminium oxide resultant＜20 % by mole Al₂O ₃+R ₂O. Be preferably≤80 % by mole of SiO₂With 〉=20 % by mole of B₂O ₃, % by mole SiO more preferably≤70₂With 25 % by mole of B₂O ₃ Better glass forms and contains alkali metal and aluminium oxide resultant＜16 % by mole Al₂O ₃+R ₂O。

In another illustrated embodiment of the present invention, light activated glass blocks is the silicic acid germanite glass, and it consists of: about 25 % by weight-45 % by weight SiO₂, about 3 % by weight-22 % by weight GeO₂, about 7 % by weight-28 % by weight B₂O ₃, the Al of about 6 % by weight-22 % by weight₂O ₃, about 6 % by weight-25 % by weight R₂O, Wherein R is the F of alkali metal and about 3 % by weight-11 % by weight, and described glass is light sensitivity after carrying hydrogen. For instance, described glass comprises about 30 % by weight-40 % by weight SiO₂, about 7 % by weight-17 % by weight GeO₂, about 10 % by weight-22 % by weight B₂O ₃, the Al of about 10 % by weight-19 % by weight₂O ₃, about 10 % by weight-22 % by weight R₂O, peace treaty＞5 % by weight F, described R₂O preferably at least a be selected from Na, The alkali-metal oxide of Li and K. In one embodiment, R is Na. At another embodiment In, R is Li. In also having an embodiment, R is K. And, in the embodiment of the present invention, R The mixture that comprises Na, Li and K. The mol ratio of alkali metal/aluminium oxide is better for about in the described glass 0.5-1.5 between. Usefully, described glass is substantially free of the oxonium ion of non-bridging bond, and this class from Son reduces from glass ingredient and removes.

According to one embodiment of the present invention, but the hydrogen content of photosensitive glass material 〉=10¹⁷H ₂Molecule/cm³ In glass, load hydrogen by known technology.

Need point out that according to embodiment of the present invention, described glass can load amount 〉=10 of hydrogen ¹⁹H ₂Molecule/cm ³Preferably can load amount 〉=2 * 10 of hydrogen ¹⁹H ₂Molecule/cm ³, and preferably can load amount 〉=5 * 10 of hydrogen according to another embodiment of the present invention ¹⁹H ₂Molecule/cm ³The high like this hydrogen amount of carrying preferably is no more than 200 ℃ by carrying the hydrogen temperature, and with molecular hydrogen (H ₂) form enter glass, and be retained among the glass with the molecular hydrogen form, do not separated by molecular hydrogen before the irradiation and do not participate in reaction until it.

But the content of the transition metal impurity of photosensitive glass≤1 ppm by weight, beavy metal impurity content≤1 ppm by weight.The iron-holder of glass is preferably≤1 ppm by weight, is more preferred from＜1 ppm by weight.The Ti amount that contains of glass is preferably≤1 ppm by weight, is more preferred from＜1 ppm by weight.But photosensitive glass has the 300nm photoabsorption less than 30dB/cm, and is preferable less than 20dB/cm, and better for 15dB/cm.Even the 250nm photoabsorption is more preferred from 10dB/cm, the best＜5dB/cm.

But photosensitive glass is preferably melten glass, and the best is non-sintered glass.The fusing point of glass≤1650 ℃, and preferable≤1600 ℃.This temperature is that the fusing of hybrid glass material powder is generated the homogeneous glass melt, forms glass through cooling again.The glass fusing point is preferable≤and 1550 ℃, better≤1500 ℃.The glass softening point temperature is preferable≤and 700 ℃.This glass generates temperature and allows to make glass effectively economically, has avoided the complicacy of sintering process and sintered glass component.

Glass preferably has wavelength and induces refraction index modulation Δ n＞10 less than 300nm ^-4(recording), and glass molecular hydrogen content＞10 at the 633nm place ¹⁷H ₂Molecule/cm ³According to embodiment, when glass of the present invention is loaded with molecular hydrogen amount＞10 ¹⁹H ₂Molecule/cm ³The time, because through radiation-induced refraction index modulation Δ n＞10 of wavelength less than 300nm light ^-4And present photosensitivity.Need point out to induce above-mentioned wavelength to induce the about 248nm-265nm of wavelength region of the best radiant light of refraction index modulation.When glass loads hydrogen, its refraction index modulation Δ n＞2 * 10 ^-4Need point out that also the irradiation wavelength can be low to moderate 244nm.

Preferable photosensitive glass piece does not contain transition metal substantially, and the photoabsorption of wavelength 300nm is less than 30dB/cm.Transition metal impurity content is preferable less than 1 ppm by weight, and the content of Fe＜1 ppm by weight, and is better＜0.1 ppm by weight.The content of Ti is preferable＜1 ppm by weight, and better＜0.1 ppm by weight.The 300nm photoabsorption of glass block is preferably＜20dB/cm, is more preferred from＜15dB/cm, be more preferred from＜10dB/cm, and the best is＜5dB/cm.Need point out effectively to reduce the level of iron, other transition metal and OH impurity.According to one embodiment of the present invention, these low impurity contents help to reduce transmission loss and then improve the homogeneity that forms grating in the glass.

Heap(ed) capacity 〉=10 when molecular hydrogen ¹⁸H ₂Molecule/cm ³The time, glass has photosensitive refraction index modulation Δ n＞10 of inducing ^-5(when 633nm, recording).A kind of like this refractive index change delta n can be shone 90 minutes with 248nm KrF excimer laser UV, and irradiation energy is 12mJ/cm ²/ pulse and obtaining.Be easy to act as most H ₂Molecule heap(ed) capacity 〉=10 ¹⁹H ₂Molecule/cm ³The time, photosensitivity Δ n＞10 that glass has ^-4The H that best glass block can load ₂Molecular weight at least 10 ¹⁹H ₂Molecule/cm ³, load temperature≤200 ℃.Year hydrogen amount＞10 of best glass ¹⁹H ₂Molecule/cm ³, and wavelength is lower than the synthetic refractive index n of photoinduction＞10 of 300nm ^-4(recording) at the 633nm place.

Glass block is non-sintered glass, and fusing point is preferable≤1600 ℃, better≤1550 ℃.The mixture of the liquid melt that the refrigerative liquid melt that glass preferably liquid melt forms and frit powder body melting preferably form.In better embodiment, glass block is the pre-type body of homogeneous glass device, and the glass hotchpotch is dispersed in the Vitrea component.Preform preferably has the specific refractory power of uniformity, and does not have pre-irradiation core (pre-radiated core) and clad region, and the component of glass is evenly distributed.

The present invention also comprises fusible silicic acid germanite glass, and this glass (for example is lower than about 10 in no-load hydrogen or low year hydrogen amount ¹⁷H ₂Molecule/cm ³, for example, even be lower than about 10 ¹⁴H ₂Molecule/cm ³) still have a photosensitivity.This silicic acid germanite glass contains the GeO of at least 2 weight % ₂(for example at least 6 weight %), and the SiO of at least 20 weight % ₂The fusing point that fusible silicic acid germanite glass has is best≤and 1650 ℃, preferable≤1550 ℃, best≤1500 ℃.For example, described glass at wavelength less than 300nm photoinduction refraction index modulation Δ n＞10 ^-4

An embodiment of the present invention comprises the UV photosensitive glass to wavelength＜300nm, and it consists of: 40-80 mole %SiO ₂, 2-15 mole %GeO ₂, 10-36 mole %B ₂O ₃, 1-6 mole %Al ₂O ₃With 2-10 mole %R ₂O, wherein R is a basic metal, described glass presents photosensitivity at no-load hydrogen and low carrying under the hydrogen.For example, glass ingredient comprises 42-73 mole %SiO ₂, 2-15 mole %GeO ₂, 25-36 mole %B ₂O ₃, 2-6 mole %Al ₂O ₃With 2-6 mole %R ₂O.Preferred glass comprises: 42-67 mole %SiO ₂, 2-15 mole %GeO ₂, 25-36 mole %B ₂O ₃, 2-6 mole %Al ₂O ₃With 2-6 mole %R ₂O.For example, described R ₂The preferably at least a alkali-metal oxide compound that is selected from Na, Li and K of O.In another embodiment, R is Na.In another embodiment, R is Li.In also having an embodiment, R is K.And in the embodiment of the present invention, R comprises the mixture of Na, Li and K.The mol ratio of basic metal/aluminum oxide is preferable between about 0.5-1.5 in the described glass.Described glass is substantially free of the oxonium ion of non-bridging bond, and this class ion reduces from glass ingredient and removes.

In another embodiment of the present invention, the photosensitive glass piece is the silicic acid germanite glass, and it consists of: about 25 weight %-45 weight %SiO ₂, about 3 weight %-22 weight %GeO ₂, about 7 weight %-28 weight %B ₂O ₃, the Al of about 6 weight %-22 weight % ₂O ₃, about 6 weight %-25 weight %R ₂O, wherein R is the F of basic metal and about 3 weight %-11 weight %, described glass presents photosensitivity at no-load hydrogen and low carrying under the hydrogen.For example, described glass comprises about 30 weight %-40 weight %SiO ₂, about 7 weight %-17 weight %GeO ₂, about 10 weight %-20 weight %B ₂O ₃, the Al of about 10 weight %-19 weight % ₂O ₃, about 10 weight %-22 weight %R ₂O, peace treaty＞5 weight %F, described R ₂The preferably at least a alkali-metal oxide compound that is selected from Na, Li and K of O.In one embodiment, R is Na.In another embodiment, R is Li.Also have an embodiment, R is K.And in the embodiment of the present invention, R comprises the mixture of Na, Li and K.The mol ratio of basic metal/aluminum oxide is preferable between about 0.5-1.5 in the described glass.Described glass is substantially free of the oxonium ion of non-bridging bond, and this class ion reduces from glass ingredient and removes.

The transition metal impurity content of photosensitive glass≤1 ppm by weight, heavy metal content≤1 ppm by weight.The iron-holder of glass is preferably≤1 ppm by weight, is more preferred from＜1 ppm by weight.The Ti amount that contains of glass is preferably≤1 ppm by weight, is more preferred from＜1 ppm by weight.Photosensitive glass has the 300nm photoabsorption less than 30dB/cm, and is preferable less than 20dB/cm, and better for 15dB/cm.Even the 250nm photoabsorption is more preferred from 10dB/cm, the best＜5dB/cm.

Photosensitive glass is preferably melten glass, and the best is non-sintered glass.The fusing point of glass≤1650 ℃, and preferable≤1600 ℃.This temperature is that the fusing of hybrid glass material powder is generated the homogeneous glass melt, forms glass through cooling again.The glass fusing point is preferable≤and 1550 ℃, better≤1500 ℃.The glass softening point temperature is preferable≤and 700 ℃.This glass generates temperature and allows to make glass effectively economically, the complicacy of having avoided sintering process and sintered glass to form.In better embodiment, glass block is a homogeneous glass device preform, and the glass hotchpotch is dispersed in the vitreum composition.Preform preferably has the specific refractory power of uniformity, and does not have pre-irradiation core (pre-radiated core) and clad region, and the component of glass is evenly distributed.

Glass preferably has wavelength and induces refraction index modulation Δ n＞10 less than 300nm ^-4(recording at the 633nm place), glass is at no-load hydrogen or low carry hydrogen and less than irradiation under the 300nm here.According to embodiment, glass of the present invention is because through radiation-induced refraction index modulation Δ n＞10 of wavelength less than 300nm light ^-4And present photosensitivity.Need point out to induce the about 248nm-265nm of wavelength region of the best radiant light of refraction index modulation with above-mentioned wavelength.Best described glass induce refraction index modulation Δ n＞2 * 10 ^-4Need point out that also the irradiation wavelength can be low to moderate 244nm.No-load hydrogen or the low glass that carries hydrogen require higher irradiation flux just can be equivalent to similar year hydrogen glass.For example, under given UV irradiation flux, carry hydrogen glass and after 8 minutes, obtain variations in refractive index 10 ^-4, and want 64 minutes under the no-load hydrogen situation.

The present invention includes the method for making refractive index pattern.Preferable methods comprises makes the refractive index pattern grating.The method of pattern-making comprises provides a 300nm photoabsorption less than 30dB/cm, best photosensitive glass piece less than 20dB/cm.Described method comprises provides the optical emitter of wavelength less than 300nm, and produces the optical radiation of wavelength less than 300nm.Method comprises with wavelength and generates pattern less than 300nm irradiation, and the photosensitive glass piece expose under this pattern and in described glass block the synthetic refractive index pattern of generation.The glass block that is provided is at 300nm photoabsorption＜15dB/cm, and is preferable＜10dB/cm, the best＜5dB/cm.The pattern that generates preferably includes and generates a pattern, and the photosensitive glass piece expose under this pattern and in described glass block the synthetic refractive-index grating of generation.

Providing the photosensitive glass piece to preferably include provides basic metal boron-aluminium-silicate glass.The block vitreum that provides is preferably in uniformity on component and the specific refractory power, and does not have isolating core/clad region.

The photosensitive glass piece that provides comprises provides non-sintered glass, or melten glass.The fusing point of described melten glass≤1,650 ℃, and preferable≤1,600 ℃, better≤1,550 ℃, best≤1,500 ℃.The photosensitive glass piece that provides is basic metal boron-aluminium-silicate glass batch of material, it is fused into basic metal boron-aluminium-silicate glass melt process comprises that the cooled glass melt becomes glass block, and fusion comprises the glass melt of heating glass matter liquid state.And make described glass melt become the refrigerative vitreum, as glass melt is flowed into the cooling zone by an eyelet.

In one embodiment of the present invention, the glass block that is provided can be the glass block that loads molecular hydrogen.Method comprises provides fused glass block, and loads at least 10 ¹⁸H ₂Molecule/cm ³Described glass block loads at least 10 ¹⁹H ₂Molecule/cm ³, and be more preferred from least 5 * 10 ¹⁹H ₂Molecule/cm ³Load temperature＜200 ℃ of molecular hydrogen, the temperature that loads molecular hydrogen is preferable＜150 ℃, and the temperature that loads molecular hydrogen is better＜and 100 ℃.Load at least 20 normal atmosphere of pressure of molecular hydrogen, and better be that 100 normal atmosphere are mixed hydrogen at least.Load hydrogen technology and can H be housed ₂Carry out in the elevated temperature vessel of gas and glass block.Glass block preferably has the glass of certain volume and surface-area physics magnitude, and enough hydrogen amounts of carrying can be provided, and preferably approaches preform and the shape that will make optics.Described glass block loads the time sufficiently long of hydrogen and effectively, makes glass block centre H under high hydrogen-pressure ₂Molecular conecentration is to load 90% of nitrogen atmosphere on every side at least.As it will be understood by those skilled in the art that the glass that is provided can be no-load hydrogen or the low hydrogen glass that carries, and still has photosensitivity.

The exposure photosensitive glass preferably includes by inducing refractive index n 〉=10 ^-5, and best Δ n 〉=10 ^-4(still record) and generation pattern at 633nm place.

Present method comprises that making can load the method for molecular hydrogen photosensitive glass optical device preform.Making preform method comprises provides the germanium oxide silicon oxide together with transition metal impurity content≤1ppm heavy metal.Method comprises the melt oxidation silicon frit, generates the homogeneous glass melt, then glass melt is chilled to transmissive UV, and the 300nm photoabsorption is less than the glass block of 20dB/cm, and glass block is made the optical device preform.Glass block is made the optical device preform to be comprised described glass block is carried molecular hydrogen amount at least 10 ¹⁸H ₂Molecule/cm ³, and preferably at least 10 ¹⁹H ₂Molecule/cm ³

Providing germanium oxide silicon oxide material package to draw together provides basic metal boron-aluminium-silicate batch of material, and at melt temperature≤1,650 melten glass, preferable≤1,600 ℃ of fusions are more preferably under≤1,550 ℃ of fusion, and the best≤1,500 ℃ of fusion.Making method comprises topples over glass melt and generates the glass block, better glass melt is flow through an eyelet.Make preformed glass part and comprise the vitreum that generates preform, its minimum size is greater than 5 μ m.

The present invention comprises that also photosensitive glass optical device refractive index pattern preform is used for UV photogenerated refractive index pattern, described preform is made up of less than basic metal boron-aluminium-silicate glass of 20dB/cm the 300nm photoabsorption, the derivable refraction index modulation Δ of 300nmUV wavelength light n＞10 of described preform ^-5, described glass block presents photosensitivity owing to expose at 300nm or under less than the 300nm wavelength.Described glass molecular hydrogen content between exposure period is at least 10 ¹⁸H ₂Molecule/cm ³The derivable refraction index modulation Δ of UV light n＞10 of preferable described preform ^-4, its molecular hydrogen content at least 10 ¹⁹H ₂Molecule/cm ³Described glass block preform is at 300nm photoabsorption＜15dB/cm, and is preferable＜10dB/cm, the best＜5dB/cm.Described basic metal boron-aluminium-silicate glass preform preferably adopts smelting process generation melten glass to belong to non-sintered glass.

Embodiment

The present invention includes fused and load H ₂The silicate compositions of the alkali-aluminium of molecule-boron-germanium, the photoinduced variations in refractive index of its UV is big.

The UV irradiation that utilizes comprises the light of CW 244nm and the light of pulse KrF excimer laser 248nm.Need point out that 268nm, 270nm, 280nm and the 290nm radiation of tunable Nd/YAG laser apparatus emission can be used for the occasion of KrF laser apparatus.The refraction index modulation that records (at the 633nm place) glass block is in 2-3 * 10 ^-4Scope.

Can think, carry hydrogen molecule, and the ability of photoreaction depends on that composition, the UV spectrum behind the glass block pre-irradiation and the inductive specific refractory power size of glass and the OH absorption that infrared (IR) spectrum records (OH stretching vibration) increase closely related.

As shown in Figure 6, make Bragg grating by phase mask from end face irradiation, shown the transmissivity and the reflectivity that record from glass block sample (glass is formed the Glass 5g of table).

For melten glass is provided, the present invention adopts various components to make glass softer, and fusing point is lower.These components comprise basic metal, aluminum oxide and boron, make fusing point reduce, and viscosity reduces.In a better embodiment, the frit fusing point is that the capacity fluorochemical reduces in the employing glass ingredient.For example Glass 4b (referring to table 10 glass ingredient table) adopts aluminum fluoride, and wherein F content is about 3.3 weight %.In better embodiment, the F amount that reduces the fusing point of batch of material composition is≤10 weight %, for example≤6 weight %.Realize reducing the frit fusing point, the element of admixture can not make the glass first-harmonic absorb and move to 248nm (5eV) in addition.

For example, the first-harmonic ABSORPTION EDGE of pure silicon dioxide edge is by the 2p track (valence band) of oxygen and the sp of silicon ³The bands of a spectrum transition decision that nonbonding track (road band) overlaps.Add basic metal and introduce other one group of relevant bands of a spectrum of the oxygen with non-bridging bond.If it is enough high to add concentration, new bands of a spectrum can appear on original valence band, thereby make the first-harmonic ABSORPTION EDGE along moving towards the long wave direction.On the other hand, interpolation is minimum to the influence on ABSORPTION EDGE edge such as boron, aluminium and the netted substitution ion of germanium one class.

Such as transition metal ion or heavy metal ion impurities is not the people for adding among the glass, and they are derived from frit, crucible, smelting furnace or the making processes, but must be controlled at＜1ppm.Even these ion amounts seldom, UV ABSORPTION EDGE edge also there is very big negative effect.

The present invention includes and make SiO ₂-GeO ₂Glass block, described glass block can fusions, and by conventional raw material, place restrictions on the amount of other component and make, make glass keep high-transmission rate at the 248nm place, and, have the softening temperature (softening temperature is preferably lower than 700 ℃) that is about 600 ℃ in rational temperature (1650 ℃) fusion down.

Glass is made by pure starting raw material, and it is low that special quartz sand contains the Fe amount.Raw material fusion 16 hours when temperature is 1550 ℃ in clean platinum crucible.In the primary sample operation, pour glass into pallet (patties), again annealing.Judge the improvement of glass quality from defective (striped) and heart yearn (cord), adopt semicontinuous scorification, glass is not directly poured out in the melt crucible, can cause many stripeds like this, but flows out by an eyelet.

Loading hydrogen is at Parr ^TMIn the pressure reactor, loading temperature is 150 ℃, carries out under 100 atmospheric pressure.Infrared spectra adopts Nicolet ^TMFTIR spectrophotometer H ₂Molecule content.

Figure 1 shows that basic metal-aluminium-boron-silicate one class glass, GeO ₂The variation of content is to the influence of absorption spectrum, and wherein said glass comprises R ₂O (3-4mol%), Al ₂O ₃(3-4mol%), B ₂O ₃(25-35mol%), GeO ₂(2.5-15mol%), and SiO ₂(66.5-42mol%).In all situations, less than under the 300nm, 248nm is the wavelength of UV radiation excitation at wavelength, and we can keep very high transmission rate.

We place pressure with the sample of each system collection is 100 normal atmosphere, and temperature is in 150 ℃ the pure hydrogen atmosphere, to mix hydrogen in sample.Adopting comparatively high temps to quicken hydrogen only is several millimeters sample internal diffusion processes at thickness, and also is unlikely to take place thermal response.We use IR spectrophotometer molecular hydrogen content.Glass of the present invention has obtained photosensitivity after loading molecular hydrogen.Obtain carrying the hydrogen amount up to 5 * 10 ¹⁹H ₂Molecule/cm ³

In order to measure the photoinduced photosensitivity of UV, we carry hydrogen on the thick glass block sample of 0.5mm, then it is absorbed mask by chromium matter and expose, and grating space is 10 μ m.The UV irradiation source is by the KrF excimer laser of long operation at 248nm.Peaking flux is 20-60mJ/cm when 50Hz ²/ pulse, irradiation time are 5-120 minute.

After the exposure of UV light, sample is through the He-Ne of spatial filtering laser illumination.Induce phase place grating diffration efficient from the 1st grade of ratio measurement with the 0th grade of intensity.As long as diffraction efficiency relatively a little less than, we just can adopt following simple formula counting yield:

$\mathrm{Eff}={\left(\frac{\mathrm{\π\ΔnL}}{\mathrm{\λ}}\right)}^2---\left(1\right)$

Here, Δ n is that refraction index modulation changes (n=n ₀+ Δ ncos (2z/ Λ)).

L is a grating refractive index, and Λ is the refractive index pattern cycle.

For alkali-aluminium of the present invention-boron-silicate glass, induce specific refractory power 1 * 10 with what record behind the fixed 248nmUV photoirradiation ^-4-3 * 10 ^-4Within the scope.Fig. 2 a is that the specific refractory power of inducing that records is the function of time shutter under fixing flux.Fig. 2 b is that the specific refractory power of inducing that records is the function of exposure flux under the set time.The latter square represents with flux.

One group of GeO ₂Content fixed glass loads hydrogen, and exposes under 248nmUV light.What the glass ingredient table provided is component, and the hydrogen amount of loading and this group glass are through the variations in refractive index of 248nm induced with laser.

Generate the sample of grating by heating, and remeasure its grating efficiency under Heating temperature over time and then investigate the thermostability of inducing variations in refractive index.Figure 3 shows that sample be heated to 400 ℃ after specific refractory power over time.

We make the non-sintered glass piece of fusion, when loading H ₂When molecule content was high, the amplitude of its UV photoinduction variations in refractive index was similar to vapour deposition, the amplitude seen in the glass of flame or plasma sintering.This meets our viewed phenomenon, and promptly preferred glass is through recording H with IR spectrum ₂Molecule content＞10 ¹⁸H ₂Molecule/cm ³, we record UV photoinduction specific refractory power considerable change.

With the molecule be media UV photoinduction photosensitivity mechanism as and if additive method, as the SiO of vapour deposition process and sintering process rather than scorification preparation ₂-GeO ₂Material is seen to be that the mechanism of media is consistent with H.Figure 4 shows that OH concentration (recorded by the OH stretching vibration, see illustration) with the relation of inducing specific refractory power to increase, this relation also can be from Fig. 5 finding.The UV photoabsorption changes also very greatly behind the irradiation.

We have observed the stress that the UV photoirradiation produces.This means volume change.We record the variation of volume corresponding to density from birefringent phenomenon.Compare with the total Δ n value that records, this effect refractive index distribution influence is very little.

As shown in Figure 6, Glass 5g glass block sample (5 * 5 * 5mm in the glass ingredient table ³) utilize phase mask to produce refractive index pattern with cycle big area (wide face) exposure of satisfying Prague 1550nm condition through 244nmCW laser apparatus (0.35W, the UV irradiation time is best for 30-60 minute).Grating length is 2.5nm.Figure 6 shows that grating reflection rate and transmissivity.Illustration is represented geometric condition and the reflectivity and the transmissivity measurement of irradiation.From grating transmissivity measurement (reducing 1.5-2db) corresponding to 30-40% reflectivity the grating length 2.5nm.Calculate 1550nm place refraction index modulation and be changed to 0.12-0.14 * 10 ^-3Figure 7 shows that the refractive index pattern grating that generates in the preformed glass part glass block.Fig. 7 a is the cross section of refractive index pattern grating in the expression preformed glass part glass block.

Improve the photosensitivity of glass when the UV irradiation test of present embodiment explanation adopts the method that loads hydrogen, need point out that present embodiment glass does not load hydrogen and carries under the low situation of hydrogen amount and also be photosensitivity.Do not load hydrogen/low year longer time shutter of hydrogen glass requirement or higher exposure flux and just can obtain specified variations in refractive index.

Glass 4b is a preferred ingredient of the present invention in the glass ingredient table.The weight percentage of batch ingredients is 35.8 weight %SiO ₂, 21.5 weight %GeO ₂, 4.48 weight %Al ₂O ₃, 3.38 weight %F, 1.31 weight %Li ₂O and 33.5 weight %B ₂O ₃The raw material powder pellet is worn into uniform compound.For SiO ₂, adopting the trade mark is the high-purity ground quartz of IOTA-6, it contains Fe impurity less than 0.1ppm, and available from Unimin company, Spruce Pine, NC 28777.For GeO ₂, adopt high-purity germanium dioxide powder, as chemical grade No.1-29/99.999%GeO ₂Available from Electro-Optic Materials Dept., Eagle-Picher Technologies, LLC, Quapaw, OK 74363, wherein contain＜0.1% muriate≤1ppm Fe, ≤ 1ppm Mg, ≤ 0.5ppm Ni, Pb do not detect (detect and be limited to 1ppm), no Zn (detect and be limited to 10ppm).For aluminium, adopt the high purity aluminium oxide powder, be 99.999% gama-alumina as purity, available from Alfa Aesar, Johnson Mathey Company, Ward Hill, MA 01835.For aluminium, also can adopt high-purity aluminum fluoride, as the trade mark be the aluminum fluoride of Alufluor available from LidoChem, Hazlet, NJ 07730.For lithium, adopt Quilonum Retard, as purity greater than 99% technical grade Quilonum Retard, available from FMC Corp., Lithium Div., Gastonia, NC 28054, wherein contain Fe ₂O ₃≤ 0.004 weight % and Cl ^-≤ 0.01 weight %.Also can adopt crystalline lithium nitrate for lithium, as VWR Scientific, Rochester, NY 14603 products.For boron, adopt boron oxide, as high-pure anhydrous boric acid, available from Stetson Chemicals, Inc., 391 Exchange St., Buffalo, NY 14204.As shown in Figure 8, the raw mix powder behind the ball milling is packed in the vertical garden tubular stove 100 of liner platinum.The gross weight of the interior material of stove (100) is 25kg, with the semicontinuous method operation.

Fusion when compound powder 101 is 1,550 ℃ in temperature.Vertical heater (100) comprises that agitator 102 is used for stirred glass melt 104, provides uniform glass melt.Vertical heater (100) comprises the eyelet 108 of feed opening 106 and feed opening, is used to transfer vitreum 110.Vitrea stock size be 105 * 4 * 4 inches (3.81 * 10.16 * 10.16cm) and in the time of 414 ℃ annealing.Annealed vitreum is cut, grinds, polishes, become the little vitreum 120 of rectangular parallelepiped profile.Little vitreum 120 is of a size of 5 * 5 * 3mm ³As shown in Figure 9, vitreum 120 in 100 atmospheric hydrogen atmospheres 210, is mixed hydrogen to vitreum preform 120 in high pressure vessel 200.

Other embodiment of the present invention contains higher aluminum oxide and fluorine than the glass on the glass ingredient table.For example, Glass 18 components comprise 34.7 weight %SiO ₂, 11.2 weight %GeO ₂, 16.4 weight %Al ₂O ₃, 1.66 weight %Na ₂O, 12.9 weight %K ₂O, 15.9 weight %B ₂O ₃With 7.23 weight %F.Glass 19 components comprise 34.51 weight %SiO ₂, 16.71 weight %GeO ₂, 13.6 weight %Al ₂O ₃, 1.32 weight %Na ₂O, 10.8 weight %K ₂O, 15.81 weight %B ₂O ₃With 7.23 weight %F.Glass melting method is similar to aforesaid method, with reference to glass ingredient table 1.These glass have loading hydrogen, and low photosensitivity of carrying hydrogen/no-load hydrogen is roughly with equivalence noted earlier.

The present invention has done detailed description together with embodiment.Obviously, to those skilled in the art, grasped key of the present invention and obviously can modify the present invention.This class is revised with variation and all is included within this claim.

Claims (82)

1. fusile photosensitive glass, molecular hydrogen content 〉=10 of described glass ¹⁷H ₂Molecule/cm ³

2. glass as claimed in claim 1 is characterized in that: described glass is the silicic acid germanite glass.

3. glass as claimed in claim 1 is characterized in that: described glass comprises basic metal boron-aluminium-silicate glass, its fusing point≤1,650 ℃, and the batch of material of described basic metal boron-aluminium-silicate glass is formed and is comprised≤85 moles of %SiO ₂%, 〉=10 moles of %B ₂O ₃, 〉=2 moles of %GeO ₂And basic metal and aluminum oxide resultant＜20 mole %Al ₂O ₃+ R ₂O, the amount that described glass can load molecular hydrogen is at least 10 ¹⁸H ₂Molecule/cm ³

4. glass as claimed in claim 3 is characterized in that: have≤70 moles of %SiO ₂With 〉=25 moles of %B ₂O ₃Batch of material form.

5. glass as claimed in claim 1 is characterized in that: described glass is to the photaesthesia of wavelength less than 300nm, and described glass comprises 40-80 mole %SiO ₂, 2-15 mole %GeO ₂, 10-36 mole %B ₂O ₃, 1-6 mole %Al ₂O ₃And 2-10 mole %R ₂O, wherein R is a basic metal.

6. glass as claimed in claim 5 is characterized in that: described glass comprises 42-73 mole %SiO ₂, 2-15 mole %GeO ₂, 20-36 mole %B ₂O ₃, 2-6 mole %Al ₂O ₃And 2-8 mole %R ₂O.

7. glass as claimed in claim 5 is characterized in that: described glass comprises 42-67 mole %SiO ₂, 2-15 mole %GeO ₂, 25-36 mole %B ₂O ₃, 2-6 mole %Al ₂O ₃And 2-6 mole %R ₂O,

8. glass as claimed in claim 5 is characterized in that: described R is the basic metal of at least a Na of being selected from, Li and K.

9. glass as claimed in claim 5 is characterized in that, transition metal impurity amount≤1 ppm by weight.

10. glass as claimed in claim 5 is characterized in that, beavy metal impurity amount≤1 ppm by weight.

11. glass as claimed in claim 5, wherein Fe content＜1 ppm by weight.

12. glass as claimed in claim 5, the wherein content of Ti＜1 ppm by weight.

13. glass as claimed in claim 5 is characterized in that: the ratio of basic metal/aluminum oxide is in 1 ± 0.5 scope in the described glass.

14. glass as claimed in claim 5, its medium wavelength is less than the photoinduced refraction index modulation Δ of 300nm n＞10 ^-4

15. glass as claimed in claim 1 is characterized in that: described molecular hydrogen content is to be carried in the described glass, and described content 〉=1018H ₂Molecule/cm ³

16. glass as claimed in claim 1 is characterized in that: described molecular hydrogen content is to be carried in the described glass, and described content 〉=1019H ₂Molecule/cm ³

17. glass as claimed in claim 1 is characterized in that, the 300nm photoabsorption is less than 20dB/cm.

18. glass as claimed in claim 1 is characterized in that: refraction index modulation Δ n 〉=2 * 10 of described glass ^-4

19. glass as claimed in claim 1 is characterized in that: the fusing point of described glass≤1,650 ℃.

20. glass as claimed in claim 1 is characterized in that: the fusing point of described glass≤1,600 ℃.

21. glass as claimed in claim 1 is characterized in that: the fusing point of described glass≤1,550 ℃.

22. glass as claimed in claim 1 is characterized in that: the fusing point of described glass≤1,500 ℃.

23. glass as claimed in claim 1 is characterized in that: the softening temperature of described glass＜700 ℃.

24. glass as claimed in claim 1 is characterized in that: when described molecular hydrogen content＞10 ¹⁹H ₂Molecule/cm ³The time, the wavelength of described glass is less than the photoinduced refraction index modulation Δ of 300nm n＞10 ^-4

25. glass as claimed in claim 2 is characterized in that: when described glass loads molecular hydrogen, and exposure is in UV light the time, and the OH content of described glass increases.

26. glass as claimed in claim 2 is characterized in that: described glass OH content is at 100-1, between 000 ppm by weight.

27. glass as claimed in claim 1 is characterized in that: described glass comprises about 25-45 weight %SiO ₂, about 3-22 weight %GeO ₂, about 7-28 weight %B ₂O ₃, about 6-22 weight %Al ₂O ₃, about 6-25 weight %R ₂O, R wherein are basic metal and about 3-11 weight %F.

28. glass as claimed in claim 27 is characterized in that: the SiO of described glass ₂Content is between about 30-40 weight %.

29. glass as claimed in claim 27 is characterized in that: the GeO of described glass ₂Content is between about 7-17 weight %.

30. glass as claimed in claim 27 is characterized in that: the B of described glass ₂O ₃Content is between about 10-22 weight %.

31. glass as claimed in claim 27 is characterized in that: the Al of described glass ₂O ₃Content is between about 10-19 weight %.

32. glass as claimed in claim 27 is characterized in that: the R of described glass ₂O content is between about 10-20 weight %.

33. glass as claimed in claim 27 is characterized in that: the F content of described glass is between about 5-11 weight %.

34. glass as claimed in claim 27 is characterized in that: the ratio of basic metal/aluminum oxide is between about 0.5-1.5 in the described glass.

35. glass as claimed in claim 1, wherein F content is≤10 weight %.

36. glass as claimed in claim 1, wherein F content is≤6 weight %.

37. a fusible photosensitive silicic acid germanite glass material, the molecular hydrogen content of described glass material is less than about 10 ¹⁷H ₂Molecule/cm ³

38. glass as claimed in claim 37 is characterized in that: described glass comprises basic metal boron-aluminium-silicate glass, its fusing point≤1,650 ℃, and the batch of material of described basic metal boron-aluminium-silicate glass is formed and is comprised≤85 moles of %SiO ₂, 〉=10 moles of %B ₂O ₃, 〉=2 moles of %GeO ₂And basic metal and aluminum oxide resultant＜20 mole %Al ₂O ₃+ R ₂O.

39. glass as claimed in claim 38 is characterized in that: described glass has≤70 moles of %SiO ₂With 〉=25 moles of %B ₂O ₃Batch of material form.

40. glass as claimed in claim 37 is characterized in that: described glass is to the photaesthesia of wavelength less than 300nm, and described glass comprises 40-80 mole %SiO ₂, 2-15 mole %GeO ₂, 10-36 mole %B ₂O ₃, 1-6 mole %Al ₂O ₃And 2-10 mole %R ₂O, wherein R is a basic metal.

41. glass as claimed in claim 40 is characterized in that: described glass comprises 42-73 mole %SiO ₂, 2-15 mole %GeO ₂, 20-36 mole %B ₂O ₃, 2-6 mole %Al ₂O ₃And 2-8 mole %R ₂O.

42. glass as claimed in claim 40 is characterized in that: described glass comprises 42-67 mole %SiO ₂, 2-15 mole %GeO ₂, 25-36 mole %B ₂O ₃, 2-6 mole %Al ₂O ₃And 2-6 mole %R ₂O.

43. glass as claimed in claim 40 is characterized in that: described R is the basic metal of at least a Na of being selected from, Li and K.

44. glass as claimed in claim 40 is characterized in that: the ratio of basic metal/aluminum oxide is between about 0.5-1.5 in the described glass.

45. glass as claimed in claim 40 is characterized in that, wavelength is less than the photoinduced refraction index modulation Δ of 300nm n＞10 ^-4

46. glass as claimed in claim 37 is characterized in that: the molecular hydrogen content of described glass material is less than about 10 ¹⁴H ₂Molecule/cm ³

47. glass as claimed in claim 37 is characterized in that, wavelength 300nm photoabsorption is less than 20dB/cm.

48. glass as claimed in claim 37 is characterized in that: refraction index modulation Δ n 〉=2 * 10 of described glass ^-4

49. glass as claimed in claim 37 is characterized in that: the fusing point of described glass≤1,650 ℃.

50. glass as claimed in claim 37 is characterized in that: the fusing point of described glass≤1,600 ℃.

51. glass as claimed in claim 37 is characterized in that: the fusing point of described glass≤1,550 ℃.

52. glass as claimed in claim 37 is characterized in that: the fusing point of described glass≤1,500 ℃.

53. glass as claimed in claim 37 is characterized in that: the softening temperature of described glass＜700 ℃.

54. glass as claimed in claim 37 is characterized in that: described glass comprises about 25-45 weight %SiO ₂, about 3-22 weight %GeO ₂, about 7-28 weight %B ₂O ₃, about 6-22 weight %Al ₂O ₃And about 6-25 weight %R ₂O, wherein R is basic metal and about 3-11 weight %F.

55. glass as claimed in claim 54 is characterized in that: the SiO of described glass ₂Content is between about 30-40 weight %.

56. glass as claimed in claim 54 is characterized in that: described glass GeO ₂Content is between about 7-17 weight %.

57. glass as claimed in claim 54 is characterized in that: the B of described glass ₂O ₃Content is between about 10-22 weight %.

58. glass as claimed in claim 54 is characterized in that: the Al of described glass ₂O ₃Content is between about 10-19 weight %.

59. glass as claimed in claim 54 is characterized in that: the R of described glass ₂O content is between about 10-20 weight %.

60. glass as claimed in claim 54 is characterized in that: the F content of described glass is between about 5-11 weight %.

61. glass as claimed in claim 54 is characterized in that: the ratio of basic metal/aluminum oxide is between about 0.5-1.5 in the described glass.

62. a method of making refractive index pattern, described method comprises:

The photosensitive glass of 300nm photoabsorption less than 20dB/cm is provided;

The source of radiation and generation wavelength optical radiation less than 300nm of wavelength less than 300nm are provided;

With the optical radiation formation pattern of described wavelength less than 300nm;

Described photosensitive glass piece is exposed into described pattern and in described glass block, generate the refraction index modulation pattern.

63. method as claimed in claim 62 is characterized in that: the photosensitive glass piece that provides is basic metal boron-aluminium-silicate glass.

64. method as claimed in claim 62 is characterized in that: the photosensitive glass piece that provides is the silicic acid germanite glass.

65. method as claimed in claim 62 is characterized in that: the photosensitive glass piece that provides is the vitreum with even composition.

66. method as claimed in claim 62 is characterized in that: the photosensitive glass that provides is non-sintered glass.

67. method as claimed in claim 62 is characterized in that: the photosensitive glass that provides is a fused glass.

68. method as claimed in claim 62 is characterized in that: the photosensitive glass that provides is basic metal boron-aluminium-silicate glass batch of material, and described glass batch materials is melt into basic metal boron-aluminium-silicate glass melt.

69. method as claimed in claim 62 is characterized in that: the photosensitive glass that provides is for loading the glass block of molecular hydrogen.

70. method as claimed in claim 62 is characterized in that: the photosensitive glass that provides is to carry hydrogen amount at least 10 ¹⁸H ₂Molecule/cm ³Melten glass.

71. method as claimed in claim 62 is characterized in that: Δ n 〉=10 that in glass, form pattern through exposure ^-4

72. a making can load the method for the photosensitive glass optical device preform of molecular hydrogen, described method comprises:

Provide a kind of germanium oxide silica glass, the 1ppm of the transition metal that is wherein stain amount≤transition metal pollutant weight, and the 1ppm of the heavy metal that is stain amount≤weight alkali metal pollutant weight;

Described silicate glass batch of material is melt into the homogeneous glass melt;

Described glass melt is cooled to the glass block of transmissive UV light, and its 300nm photoabsorption is less than 20dB/cm;

Described glass block is made the optical device preform.

73., it is characterized in that also comprising molecular hydrogen content at least 10 is provided as method as described in the claim 72 ¹⁷H ₂Molecule/cm ³Glass.

74., it is characterized in that as method as described in the claim 72 :≤1, fusion under 650 ℃ of temperature.

75. as method as described in the claim 72, it is characterized in that: the silica glass material that provides is basic metal boron-aluminium-silicate glass material.

76. as method as described in the claim 72, it is characterized in that: the silica glass material that provides is a silicic acid germanite glass material.

77. as method as described in the claim 72, it is characterized in that, comprise and topple over described glass melt.

78. as method as described in the claim 72, it is characterized in that, comprise described glass melt is flow through an eyelet.

79. as method as described in the claim 72, it is characterized in that: the preform step that forms optical device comprises the preform of formation minimum size＞5 μ m.

80. the preform of photosensitive glass optical device refractive index pattern, form refractive index pattern with UV light, described preform comprises the basic metal boron-aluminium-silicate glass of 300nm photoabsorption less than 20dB/cm, the derivable refraction index modulation Δ of UV wavelength light n＞10 of described refractive index pattern preform ^-5, its molecular hydrogen content at least 10 ¹⁸H ₂Molecule/cm ³

81., it is characterized in that: the derivable refraction index modulation Δ of UV light n＞10 of described refractive index pattern preform as refractive index pattern preform as described in the claim 80 ^-4, its molecular hydrogen content at least 10 ¹⁹H ₂Molecule/cm ³

82. as refractive index pattern preform as described in the claim 80, it is characterized in that: described basic metal boron-alumina silicate glass is a kind of fused glass.

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