The homogenizing preparation method of rear-earth-doped quartz glass bar
Technical field
The present invention relates to preform and laser glass, especially a kind of large mode field mixes rare earth prefabricated quartz fiber rod core
The homogenizing preparation method of the preparation method of stick and quartzy base laser glass.
Background technique
For meet industrial process applications higher laser power requirement, while reducing the list of rear-earth-doped silica fibre again
Position area laser load power, reduces nonlinear effect and damage from laser, high-power laser optical fiber is towards large mode field optical fiber
Direction develop.Since two thousand four, Southampton University of Southampton (Optics Express, 2004, Vol.12, No.25,
Pp.6088-6092) and Jena photon technology research institute, Germany joint Heraeus company (SPIE proceedings, 2008
Volume 6873, pp.687311-1-9) carry out the development work that large mode field mixes Yb special optical fiber.
The preparation method of rear-earth-doped prefabricated quartz fiber rod more mature at present is improved chemical vapor deposition
(MCVD) binding soln infusion method.The disadvantages of this method are: due to the limitation of uniform doping and doping process stress control, very
Hardly possible realizes the preparation of the rear-earth-doped rock quartz core rod of big core diameter.Germany Heraeus company disclosed in 2010 and Germany's Jena light
A United States Patent (USP) (2010/0251771 A1 of US) for sub- technical research institute's joint application proposes a kind of doped silica glass
Preparation method.AlCl is added from the ammonia spirit of the oxidation silicon nano power containing 50wt% in this method3,YbCl3Aqueous solution,
Form Uniform Doped Al3+,Yb3+The SiO of ion2Particle.By granulation, drying, isostatic pressing, dehydration, sintering and vitrifying,
Form the quartz glass of Uniform Doped.Length 200mm can be prepared using this method, diameter 15mm's mixes Yb quartz glass core
Stick, and being prepared for back end at 1200nm loss with it is that 50dB/km mixes Yb quartz large mode field rod-type optical fibre.But this method
Yb can only be realized by being limited in that3+,Al3+It is co-doped with the preparation of quartz glass plug, can not achieve Yb3+,Al3+,P5+It is co-doped with, thus
Photodarkening effect under high power laser light output applicable cases more difficult to control.And this method is with oxidation silicon nano power solid phase
It sets out, it is more difficult to fundamentally solve the problems, such as the optical homogeneity of plug glass.
A kind of patent of invention " rare earth Uniform Doped prefabricated rods of Yangtze Optical Fiber and Cable Company Ltd disclosed in March, 2013
Plug and its preparation " (publication number: 102992613 A of CN).This method is using the nano oxidized silicon powder of 10-200nm as former
Material is dissolved in pH=7-11, in water or ethanol solution containing Doped ions, obtains by being dehydrated, after granulation processing containing dopant
Silica powder.Using etc. static pressure and atmosphere sintering obtain rare-earth-ion-doped quartz glass plug.The invention is reflected
Rate fluctuates the plug glass within ± 10%.But the invention is using nano oxidized silicon raw material, is not from pure solution legal system
Standby powder, it is difficult to the homogeneity question there are many fundamentally solving in the case of Doped ions.
Seminar where the present inventor in 2013 has developed a kind of pre- with sol gel process preparation large mode field Yb dosed optical fiber
The technology of rod mandrel processed, and applied for patent of invention " preparation method for mixing Yb prefabricated quartz fiber rod plug " (patent publication No.
103373811A).The patent of invention has highlighted large-sized preparation method for mixing ytterbium plug glass, and shortcoming is glass
The content of divalent ytterbium ion and low price foreign ion in glass is still higher, causes final fibre loss still in higher level.
On the other hand, the optical homogeneity of rear-earth-doped quartz glass is still poor, is unable to satisfy the application requirement of laser glass medium.
Summary of the invention
The present invention in view of the above shortcomings of the prior art and defect, is sent out according to high-capacity optical fiber laser and solid-state laser
The demand of exhibition provides a kind of homogenizing preparation method of rear-earth-doped quartz glass bar.The rear-earth-doped stone obtained using this method
English glass bar not only can be used to prepare large scale, high uniformity large mode field double clad mixes rare earth silica fibre, but also can to prepare optics equal
The even higher rear-earth-doped quartz glass of property.
Technical solution of the invention are as follows:
A kind of homogenizing preparation method of rear-earth-doped quartz glass bar, including the following steps:
1. by diameter 6-10mm, length 50- is processed into based on rear-earth-doped quartz glass prepared by powder sintering technique
The glass bar of 200mm, which is placed on glass blower's lathe, carries out microcell heating using oxyhydrogen flame, and adjustment flame to heat high-temperature region
Length is less than 1cm, and according to chemical reaction proportionate relationship, hydrogen and oxygen react according to 2 to 1 relationship and generates moisture, in order to obtain
Oxygen-enriched atmosphere is taken, needs to increase oxygen flow, so that the flow proportional of oxygen and hydrogen is increased to 1 from conventional 0.5, heating temperature
To 2000 DEG C of -2100 DEG C of ranges, the processing of secondary high-temperature homogenizing, lathe are carried out using glassy zone of the lathe rotation to high-temperature heating
Velocity of rotation will not be advisable with rear-earth-doped quartz glass because gravity softens to fall, and usual rotation speed is 60-70 revs/min,
Oxyhydrogen flame slowly moves back and forth heating with certain speed from one end to the other side, and usual rate of flame travel is 30-40mm/ points
Clock;
2. the number that above-mentioned rear-earth-doped quartz glass bar moves back and forth heating homogenizing is 10 times -15 times;
3. oxyhydrogen flame temperature is adjusted to 1500 DEG C -1600 DEG C or so, the rear-earth-doped quartz glass completed to above-mentioned homogenizing
Mobile heating is made annealing treatment stick from one end to the other side, and rate of flame travel is 80-100mm/ minutes;
4. removing rear-earth-doped quartz glass bar after completing glass annealing, obtaining the rear-earth-doped stone of high optical homogeneity
English glass bar.
Rear-earth-doped quartz glass bar after above-mentioned reheating homogenizing is carried out optical manufacturing to obtain needed for practical application
The rear-earth-doped quartz glass bar of diameter, the glass bar both may be used as optical fiber prefabricated rod mandrel, it is also possible to make rod-shaped laser glass
Glass medium.
Beneficial effects of the present invention:
1, it can effectively improve the optical homogeneity of rear-earth-doped quartz glass;
2, the content of lower valency rare earth ion and foreign ion can be effectively reduced, raising and optical fiber conducive to luminescent properties
The reduction of loss;
Detailed description of the invention
Fig. 1 is that embodiment 1 mixes ytterbium quartz glass bar microcell heating second melting homogenizing front and back microscopic fluorescence photo comparison,
In, a is that embodiment 1 mixes micro- fluorescence photo before ytterbium quartz glass bar microcell heating second melting is homogenized, and b is that embodiment 1 mixes ytterbium stone
English glass bar microcell heats micro- fluorescence photo after second melting homogenizing.
Fig. 2 is the rear-earth-doped silica fibre that application examples mixes that ytterbium plug microcell heating second melting homogenizing front and back is prepared
Microphoto, wherein a is that application examples mixes ytterbium plug microcell and heats the rear-earth-doped quartz that is prepared before second melting homogenizing
The microphoto of optical fiber, b are that application examples mixes the rear-earth-doped quartz being prepared after ytterbium plug microcell heating second melting homogenizing
The microphoto of optical fiber.
Specific embodiment
The present invention is described further respectively below in conjunction with drawings and examples.
The rear-earth-doped quartz glass bar prepared is placed on glass blower's lathe in the present invention, using oxyhydrogen flame to core
Stick glass part microcell is heated, and plug is in rotary state when heating.Make oxygen excessive when heating, obtain oxygen-enriched atmosphere,
Under doped silica glass soft state, oxidation is carried out to glass and high temperature homogenizing is handled, to effectively reduce inside glass
Lower valency ion concentration, while greatly improving the uniformity of glass.
Embodiment 1:
The present embodiment mixes ytterbium quartz glass bar using what powder sintering technique was fired, carries out the heating of high temperature microcell, homogenizing system
The standby rear-earth-doped quartz glass bar of high quality.This method includes the following steps:
1. the glass of diameter 10mm, length 50mm will be processed into based on rear-earth-doped quartz glass prepared by powder sintering technique
Glass stick, which is placed on glass blower's lathe, carries out microcell heating using oxyhydrogen flame, and adjustment flame is less than heating high temperature section length
1cm, according to chemical reaction proportionate relationship, hydrogen and oxygen react according to 2 to 1 relationship and generate moisture, in order to obtain oxygen rich air
Atmosphere needs to increase oxygen flow, so that the flow proportional of oxygen and hydrogen is increased to 1 from conventional 0.5, heating temperature to 2000
DEG C, the processing of secondary high-temperature homogenizing is carried out using glassy zone of the lathe rotation to high-temperature heating;Lathe velocity of rotation is 60 revs/min
Clock, oxyhydrogen flame slowly move back and forth heating with 30mm/ minutes speed from one end to the other side.
2. above-mentioned rear-earth-doped quartz glass bar moves back and forth heating homogenizing 15 times, stop heating, completes high temperature and be homogenized
Journey.
3. oxyhydrogen flame temperature is adjusted to 1600 DEG C or so, the rear-earth-doped quartz glass bar completed to above-mentioned homogenizing is from one end
Low-temperature annealing processing is carried out to the mobile heating of the other end, rate of flame travel is 80mm/ minutes.
4. removing rear-earth-doped quartz glass bar after completing glass annealing, that is, the rare earth of high optical homogeneity being prepared
Doped silica glass stick.
Fluorescence Analysis is carried out to the plug glass of reheating homogenizing front and back, as a result as shown in Figure 1.It can be seen that through excessively high
Glass after warm microcell heat treatment shines and becomes more uniform.
Embodiment 2:
The present embodiment mixes ytterbium quartz glass bar using what powder sintering technique was fired, carries out the heating of high temperature microcell, homogenizing system
The standby rear-earth-doped quartz glass bar of high quality.This method includes the following steps:
1. the glass of diameter 6mm, length 200mm will be processed into based on rear-earth-doped quartz glass prepared by powder sintering technique
Glass stick, which is placed on glass blower's lathe, carries out microcell heating using oxyhydrogen flame, and adjustment flame is less than heating high temperature section length
1cm, according to chemical reaction proportionate relationship, hydrogen and oxygen react according to 2 to 1 relationship and generate moisture, in order to obtain oxygen rich air
Atmosphere needs to increase oxygen flow, so that the flow proportional of oxygen and hydrogen is increased to 1 from conventional 0.5, heating temperature to 2100
DEG C, the processing of secondary high-temperature homogenizing is carried out using glassy zone of the lathe rotation to high-temperature heating.Lathe velocity of rotation is 80 revs/min
Clock, oxyhydrogen flame slowly move back and forth heating with 40mm/ minutes speed from one end to the other side.
5. above-mentioned rear-earth-doped quartz glass bar moves back and forth heating homogenizing 10 times, stop heating, completes high temperature and be homogenized
Journey.
6. oxyhydrogen flame temperature is adjusted to 1500 DEG C or so, the rear-earth-doped quartz glass bar completed to above-mentioned homogenizing is from one end
Low-temperature annealing processing is carried out to the mobile heating of the other end, rate of flame travel is 100mm/ minutes.
7. removing rear-earth-doped quartz glass bar after completing glass annealing, that is, the rare earth of high optical homogeneity being prepared
Doped silica glass stick.
Embodiment 3:
The present embodiment is the neodymium-doped quartz glass bar fired using powder sintering technique, carries out the heating of high temperature microcell, homogenizing
Prepare high quality neodymium doped silica glass stick.This method includes the following steps:
1. the neodymium doped silica glass prepared based on powder sintering technique to be processed into the glass of diameter 6mm, length 100mm
Stick, which is placed on glass blower's lathe, carries out microcell heating using oxyhydrogen flame, and adjustment flame makes heating high temperature section length be less than 1cm,
According to chemical reaction proportionate relationship, hydrogen and oxygen are needed according to 2 to 1 relationship reaction generation moisture in order to obtain oxygen-enriched atmosphere
Increase oxygen flow, the flow proportional of oxygen and hydrogen is made to be increased to 1 from conventional 0.5, heating temperature is to 2000 DEG C, benefit
Secondary high-temperature homogenizing processing is carried out to the glassy zone of high-temperature heating with lathe rotation.Lathe velocity of rotation is 60 revs/min, hydrogen
Oxygen flame slowly moves back and forth heating with 30mm/ minutes speed from one end to the other side;
2. above-mentioned rear-earth-doped quartz glass bar moves back and forth heating homogenizing 10 times, stop heating, completes high temperature and be homogenized
Journey;
3. oxyhydrogen flame temperature is adjusted to 1600 DEG C or so, the rear-earth-doped quartz glass bar completed to above-mentioned homogenizing is from one end
Low-temperature annealing processing is carried out to the mobile heating of the other end, rate of flame travel is 100mm/ minutes;
4. after completing glass annealing, removing neodymium doped silica glass stick to get quartzy to the doping of the neodymium of high optical homogeneity
Glass bar.
Application Example
Ytterbium quartz glass bar is mixed as plug, with tiretube process drawing optical fiber, contrast test using the homogenizing preparation of embodiment 1
The microstructure of homogenizing front and back glass-pulling optical fiber, as shown in Figure 2.It can be seen that the plug glass after the heat treatment of high temperature microcell
It is obviously improved compared with inside of optical fibre optical homogeneity prepared by untreated plug.