CN117700091A - Acid washing shaping method and device for panda type polarization maintaining optical fiber preform - Google Patents

Acid washing shaping method and device for panda type polarization maintaining optical fiber preform Download PDF

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Publication number
CN117700091A
CN117700091A CN202311831795.6A CN202311831795A CN117700091A CN 117700091 A CN117700091 A CN 117700091A CN 202311831795 A CN202311831795 A CN 202311831795A CN 117700091 A CN117700091 A CN 117700091A
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China
Prior art keywords
preform
pickling
optical fiber
shaping
panda
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CN202311831795.6A
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Chinese (zh)
Inventor
田钧
石洪伟
文雁平
黄兴旺
陈智浩
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Shanghai Aoshi Control Technology Co ltd
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Shanghai Aoshi Control Technology Co ltd
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Priority to CN202311831795.6A priority Critical patent/CN117700091A/en
Publication of CN117700091A publication Critical patent/CN117700091A/en
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Abstract

The invention relates to a pickling shaping method and device for panda type polarization maintaining optical fiber preformed bars, the device comprises a pickling tank, a bearing frame, a clamp and a thickness gauge, the pickling tank comprises a tank body and a cover body, pickling liquid is arranged in the tank body, a feed inlet and a discharge outlet are arranged on the cover body, the feed inlet and the discharge outlet are communicated with the outside through pipelines, the bearing frame is arranged under the tank body and used for supporting the tank body, the clamp is arranged on two sides in the tank body and used for clamping the preformed bars, and the thickness gauge is arranged under the tank body. Compared with the prior art, the invention can greatly improve the pickling efficiency, quality and precision.

Description

Acid washing shaping method and device for panda type polarization maintaining optical fiber preform
Technical Field
The invention belongs to the technical field of optical fiber production and manufacturing, and relates to an acid washing shaping method and device for panda type polarization maintaining optical fiber preformed bars.
Background
Polarization maintaining fiber is one unique fiber and has the key characteristic of maintaining the polarization direction of light signal unchanged. In conventional optical fibers, the polarization of the light waves is susceptible to various distortions and disturbances in the transmission process, resulting in a degradation of the quality of the optical signal. However, the polarization maintaining optical fiber can remarkably inhibit the change of the polarization of the optical signal by the special structure and material design thereof, thereby ensuring the stable transmission of the optical signal. Panda-type polarization maintaining fiber is a specially designed polarization maintaining fiber, and the name of the polarization maintaining fiber is that the polarization maintaining fiber is similar to the black and white color spots of pandas in appearance. Such optical fibers are widely used in the fields of optical communication, military and the like, where stability of the transmission direction of optical signals is required to be maintained.
In the process of manufacturing the polarization maintaining optical fiber preform, there may be some defects, such as uneven surface, uneven internal stress, etc., which may adversely affect the performance of the final polarization maintaining optical fiber. To solve these problems, acid wash shaping techniques have been introduced.
The acid washing and shaping technique is a method for removing defects on the surface of a preform and eliminating internal stress thereof by immersing the preform in a specific acid solution using the corrosive action of the acid. The surface and internal structure of the preform can be finely regulated and optimized by finely controlling key parameters such as the pickling time, the acid concentration, the temperature and the like. This technique has a significant effect on improving the quality of the preform and improving the transmission performance and stability of the optical fiber. In particular, it may help reduce refractive index non-uniformity of the preform and reduce polarization mode crosstalk in the optical fiber. At the same time, the technology is also helpful for enhancing the mechanical strength and durability of the optical fiber, thereby prolonging the service life of the optical fiber.
The conventional acid washing shaping technology needs manual operation, has poor efficiency, quality and precision, and is easy to cause health threat to operators.
Patent CN206666389U discloses a three-dimensional pickling device for optical fiber perform, including pickling cavity, erect in the tubular structure's of a plurality of root in the pickling cavity tube trench, along vertical orientation setting and centre gripping tube trench's a plurality of clamping device and be located tube trench bottom central nozzle. But this patent lacks a structure for detecting the pickling quality of the preform in real time.
Patent CN204569729U discloses an optical fiber preform pickling device comprising: the device comprises a box body, a pickling tank, a pure water washing tank and a liquid injection mechanism; the pickling tank and the pure water washing tank are both arranged in the box body; the liquid injection mechanism is connected with the box body, and corresponding liquid is injected or recovered into the pickling tank and the pure water washing tank; wherein, set up the structure measurement structure of centre gripping in the box, centre gripping fixed optical fiber perform and measure its immersion in the size of pickling bath. This patent, although setting the size of the preform immersed in the pickling tank, lacks a structure for detecting the pickling condition of the preform itself in real time.
Patent CN111732335a discloses a method for repairing concentricity of an optical fiber preform, which comprises the following steps: horizontally placing the optical fiber preform with the concentricity exceeding the standard on a lifting platform in an acid tank, wherein one surface with the concentricity exceeding the standard faces downwards; the lifting platform moves vertically downwards, and acid liquor is injected into the acid tank; controlling the liquid level of the acid liquor to submerge half of the preform; controlling the pickling time and the relative height of the preform rod and the liquid level; after pickling for a certain time, lifting the lifting platform or discharging acid in the acid tank, spraying distilled water to the preform, washing off the acid liquor remained on the surface, and drying the surface of the preform by using nitrogen or compressed air. Although the patent sets the pickling time, the means for detecting the pickling quality of the preform in real time is lacking.
Disclosure of Invention
The invention aims to overcome at least one problem in the prior art and provide a pickling shaping method and device for a panda type polarization maintaining optical fiber preform.
The aim of the invention can be achieved by the following technical scheme:
according to the technical scheme, the acid washing shaping device for the panda type polarization maintaining optical fiber preformed rod comprises an acid washing groove, a bearing frame, a clamp and a thickness gauge, wherein the acid washing groove comprises a groove body and a cover body, the groove body can accommodate the length required by the preformed rod in size, acid washing liquid is arranged in the groove body, a feed inlet and a discharge outlet are formed in the cover body, the feed inlet and the discharge outlet are communicated with the outside through pipelines, the bearing frame is arranged below the groove body and is used for supporting the groove body, the clamp is arranged on two sides in the groove body and is used for clamping the preformed rod, the thickness gauge is arranged below the groove body, and because of the correlation between the thermal expansion coefficient and the thickness of the preformed rod, the thickness of the preformed rod is monitored in real time through the thickness gauge, acid washing chemical reaction is performed for corresponding time, and when the acid washing is corroded into an ellipse shape, the acid washing purpose is achieved.
Further, the structure of the cross section of the prefabricated rod comprises a core rod, a stress rod and a cladding layer which are combined into a panda shape, the cladding layer is wrapped outside the core rod and the stress rod, the core rod is arranged in the center of the cladding layer, the stress rod is symmetrically arranged on two sides of the core rod, the shape of the cross section of the prefabricated rod after pickling and shaping is elliptical, the edge area of the pickling and shaping removal cladding layer is a corrosion area, the stress rod is symmetrically distributed in the major axis direction of the ellipse, and the corrosion area is symmetrically distributed in the minor axis direction of the ellipse.
Due to the difference of thermal expansion coefficients between the stress rod and the cladding, the shape of the cross section of the preform needs to be shaped into an ellipse by pickling, and the preform can resist deformation when the subsequent temperature rises. The thermal expansion coefficient is a physical quantity introduced to characterize the process of changing the length, the area and the volume of an object when the object is heated. The thermal expansion coefficient is a linear expansion coefficient alpha, a surface expansion coefficient beta and a bulk expansion coefficient gamma. For an object that can be considered approximately as one dimension, the length is a determining factor for measuring its volume, and the thermal expansion coefficient can be defined simply as: the ratio of the increase in length per unit temperature change to the original length is the linear expansion coefficient.
When the temperature of the object increases, the average kinetic energy of the molecular motion increases, the distance between molecules also increases, and the volume of the object increases accordingly. When the temperature is lowered, the average kinetic energy of molecules becomes smaller when the object is cooled, so that the distance between molecules is shortened, and the volume of the object is reduced. The thermal expansion coefficient refers to the regularity coefficient of the change of the geometric characteristics along with the change of temperature under the action of the thermal expansion and contraction effect of the substance. The linear expansion coefficient refers to the ratio of the change in length of a solid substance when the temperature is changed by 1 c to its length at a certain temperature.
Further, the bearing frame is provided with a ventilation groove, and the prefabricated rod can be dried after pickling through the ventilation groove.
As a preferable technical scheme, the weight sensor is arranged on the bearing frame, and the weight change of the preform rod can be monitored through the weight sensor.
As the preferable technical scheme, the angle regulator is arranged on the clamp holder, and the angle of the prefabricated rod can be regulated through the angle regulator so as to adapt to the pickling demands of different angles.
As a preferable technical scheme, the thickness gauge is a laser thickness gauge.
As the preferable technical scheme, the thickness gauge is connected with the control program platform through a data line, the measurement result is transmitted to the control program platform for processing, and an operator can further adjust the time and the degree of pickling so as to control the pickling chemical reaction.
As a preferable technical scheme, the control program platform can control feeding and discharging, pickling time, angle of the prefabricated rod and thickness of a corrosion area measured by a thickness gauge.
As the preferable technical scheme, the cover body is also provided with an observation window, and the corrosion condition of the prefabricated rod in the groove body can be observed through the observation window.
Further, hydrofluoric acid is adopted as the pickling solution, and the mass fraction is 30-50%.
According to one of the technical schemes, the invention provides a pickling and shaping method of panda-type polarization-maintaining optical fiber preformed rod, which is characterized by carrying out pickling by the device, and comprising the following steps:
s1, placing a corrosion area of a preform to be close to pickling solution, and clamping two sides of the preform by the clamp;
s2, opening a range finder, opening a feed inlet, adding pickling solution to perform pickling chemical reaction, opening the range finder in the whole process, monitoring the outer diameters of a first monitoring area, a second monitoring area and a third monitoring area on the preform in real time, regulating and controlling the thickness of the preform according to a thickness meter, and regulating and controlling the time and degree of pickling according to the thickness;
s3, removing the edge area of the cladding layer of the preform through acid washing shaping to form a first corrosion area, overturning the preform by 180 degrees through a clamp holder, and acid washing shaping to form a second corrosion area;
s4, washing the preform, ultrasonic washing, washing off pickling solution on the surface of the preform, placing the preform on a bearing frame, and airing in a ventilation groove.
Further, in step S2, the first monitoring area is a head portion of the preform, the second monitoring area is a middle portion of the preform, and the third monitoring area is a tail portion of the preform.
Further, the total time of pickling in the step S3 is 23-28 hours.
Further, the number of times of flushing in step S4 is 3 to 5 times.
Further, the ultrasonic cleaning time in the step S4 is 10-40min.
Further, the air drying time in the step S4 is 18-28h.
Compared with the prior art, the invention has the following beneficial effects:
(1) Compared with manual pickling, the device provided by the invention has the advantages that the pickling efficiency, quality and precision can be greatly improved by monitoring in real time through the laser range finder, and the safety problem caused by improper operation of operators is effectively avoided;
(2) The invention prepares the panda type polarization maintaining fiber through manually controlling the time to reach the final product of pickling, then carrying out subsequent cleaning, welding, assembling and drawing, the method is simple and quick, the geometric shape of the prepared panda type polarization maintaining fiber is controllable, and the optical, polarization maintaining and mechanical properties reach the international standard;
(3) The method is simple and quick, the geometric shape of the prepared panda type polarization-preserving fiber is controllable, and the optical, polarization-preserving and mechanical properties reach international standards.
Drawings
FIG. 1 is a schematic cross-sectional view of a panda-type polarization-maintaining optical fiber preform according to an embodiment of the present invention;
FIG. 2 is a schematic diagram showing the pickling position of a panda-type polarization-maintaining optical fiber preform according to an embodiment of the present invention;
FIG. 3 is a schematic diagram showing the monitoring positions of panda-type polarization maintaining optical fiber preforms according to an embodiment of the present invention;
fig. 4 is a schematic structural diagram of an acid washing and shaping device for a panda-type polarization maintaining optical fiber preform according to an embodiment of the present invention.
The figure indicates:
1-pickling tank, 2-holder, 3-preform, 31-core rod, 32-stress rod, 33-cladding, 34-corrosion zone, 35-first monitoring zone, 36-second monitoring zone, 37-third monitoring zone and 4-pickling solution.
Detailed Description
The present invention will be described in detail with reference to specific examples. The present embodiment is implemented on the premise of the technical scheme of the present invention, and a detailed implementation manner and a specific operation process are given, but the protection scope of the present invention is not limited to the following examples.
The equipment used in the following examples is representative of conventional equipment in the art unless otherwise specified; unless otherwise indicated, all reagents used are commercially available or prepared by methods conventional in the art, and all of the following examples, not specifically described, are accomplished by means of conventional experimentation in the art.
Examples:
as shown in FIG. 1 and FIG. 2, the structure of the cross section of the panda-shaped polarization-maintaining optical fiber preform 3 comprises a mandrel 31, a stress rod 32 and a cladding 33, wherein the mandrel 31, the stress rod 32 and the cladding 33 are combined into a panda-shaped structure, the cladding 33 is wrapped outside the mandrel 31 and the stress rod 32, the mandrel 31 is arranged in the center of the cladding 33, the stress rod 32 is symmetrically arranged on two sides of the mandrel 31, the cross section of the preform 3 after pickling and shaping is elliptical, the edge area of the pickling and shaping removing cladding 33 is a corrosion area 34, the stress rod 32 is symmetrically distributed in the long axis direction of the ellipse, and the corrosion area 34 is symmetrically distributed in the short axis direction of the ellipse.
The utility model provides a pickling shaping device of panda type polarization maintaining optical fiber perform, as shown in fig. 4, including pickling tank 1, the bearing frame, holder 2 and thickness gauge, pickling tank 1 includes cell body and lid, the size of cell body can hold the required length of perform 3, be provided with pickling solution 4 in the cell body, be provided with feed inlet and discharge gate on the lid, feed inlet and discharge gate all are linked together with outside through the pipeline, be provided with the bearing frame below the cell body, the bearing frame is used for supporting the cell body, both sides are provided with holder 2 in the cell body, holder 2 centre gripping has perform 3, be provided with the thickness gauge below the cell body, because the correlation between thermal expansion coefficient and the thickness of perform 3, through thickness gauge real-time supervision perform the pickling chemical reaction in corresponding time is set for, when pickling corrodes out oval, reach the pickling purpose;
the bearing frame is provided with a ventilation groove, and the prefabricated rod 3 can be dried after pickling through the ventilation groove;
the weight sensor is arranged on the bearing frame, and the weight change of the preform 3 can be monitored through the weight sensor;
the angle regulator is arranged on the clamp holder 2, and the angle of the preform 3 can be regulated through the angle regulator so as to adapt to the pickling requirements of different angles;
the thickness gauge adopts a laser thickness gauge;
the thickness gauge is connected with the control program platform through a data line, the measurement result is transmitted to the control program platform for processing, and an operator can further adjust the time and degree of pickling so as to control the pickling chemical reaction;
the control program platform can control feeding and discharging, pickling time, angle of the preform 3 and thickness of the corrosion area 34 measured by the thickness meter;
the cover body is also provided with an observation window through which the corrosion condition of the prefabricated rod 3 in the groove body can be observed;
the pickling solution 4 adopts hydrofluoric acid with a mass fraction of 30-50%, preferably 40% in this embodiment.
The acid washing and shaping method for the panda type polarization maintaining optical fiber preform comprises the following specific steps of:
s1, placing an etching area 34 of a preform 3 close to pickling solution 4, and clamping two sides of the preform 3 by a clamp 2;
s2, opening a range finder, opening a feed inlet, adding pickling solution 4 to perform pickling chemical reaction, and as shown in fig. 3, opening the range finder in the whole process, monitoring the outer diameters of a first monitoring area 35, a second monitoring area 36 and a third monitoring area 37 on the preform 3 in real time, regulating the thickness of the preform 3 according to a thickness gauge, and regulating the pickling time and degree according to the thickness;
s3, removing the edge area of the cladding 33 from the preform 3 through acid washing and shaping to form a first corrosion area 34, turning over the preform 3 by 180 degrees through the clamp holder 2, and acid washing and shaping to form a second corrosion area 34;
s4, placing the preform 3 in a fume hood for washing by deionized water, then placing in an ultrasonic cleaner filled with deionized water for ultrasonic cleaning, washing off pickling solution 4 on the surface of the preform 3, placing the preform 3 on a bearing frame, and airing in a ventilation groove.
The first monitoring area 35 is the head of the preform 3, the second monitoring area 36 is the middle of the preform 3, and the third monitoring area 37 is the tail of the preform 3;
the total pickling time is 23-28h;
the number of flushes is 3-5, preferably 4 in this example;
the time of ultrasonic cleaning is 10-40min, preferably 20min in this embodiment;
the drying time is 18-28h, preferably 20h in this example.
By the method of the examples, the following 10 panda-type polarization maintaining optical fiber preforms were obtained, and the parameters are shown in Table 1.
TABLE 1 pickling parameters of panda type polarization maintaining optical fiber preform
As shown in Table 1, the thickness parameters of the preform 3 are basically kept stable under the same total pickling time, the geometric shape is controllable, and the optical, polarization maintaining and mechanical properties reach the international standards.
The previous description of the embodiments is provided to facilitate a person of ordinary skill in the art in order to make and use the present invention. It will be apparent to those skilled in the art that various modifications can be readily made to these embodiments and the generic principles described herein may be applied to other embodiments without the use of the inventive faculty. Therefore, the present invention is not limited to the above-described embodiments, and those skilled in the art, based on the present disclosure, should make improvements and modifications without departing from the scope of the present invention.

Claims (10)

1. The utility model provides a pickling shaping device of panda type polarization maintaining optical fiber perform, its characterized in that, the device includes pickling tank (1), bearing frame, holder (2) and thickness gauge, pickling tank (1) are including cell body and lid, be provided with pickling solution (4) in the cell body, be provided with feed inlet and discharge gate on the lid, feed inlet and discharge gate all are linked together with the outside through the pipeline, be provided with the bearing frame under the cell body, this bearing frame is used for supporting the cell body, both sides are provided with holder (2) in the cell body, and this holder (2) centre gripping has perform (3), be provided with thickness gauge under the cell body.
2. The pickling and shaping device for the panda-type polarization maintaining optical fiber preform according to claim 1, wherein the structure of the cross section of the preform (3) comprises a core rod (31), a stress rod (32) and a cladding layer (33) which are combined into a panda-type, the cladding layer (33) is wrapped outside the core rod (31) and the stress rod (32), the core rod (31) is arranged in the center of the cladding layer (33), the stress rod (32) is symmetrically arranged on two sides of the core rod (31), the cross section of the preform (3) after pickling and shaping is elliptical, the edge area of the pickling and shaping removing cladding layer (33) is an erosion area (34), the stress rod (32) is symmetrically distributed in the major axis direction of the ellipse, and the erosion area (34) is symmetrically distributed in the minor axis direction of the ellipse.
3. The acid washing and shaping device for panda-type polarization maintaining optical fiber preforms according to claim 1, wherein a ventilation groove is arranged on said bearing frame.
4. The pickling and shaping device for panda-type polarization maintaining optical fiber preforms according to claim 1, wherein the pickling solution (4) is hydrofluoric acid with a mass fraction of 30-50%.
5. A method for acid cleaning and shaping a panda-type polarization maintaining optical fiber preform, characterized in that the method is acid cleaning by the apparatus according to any one of claims 1 to 4, the method comprising the steps of:
s1, placing a corrosion area (34) of a preform (3) to be close to pickling solution (4), and clamping two sides of the preform (3) by the clamp holder (2);
s2, opening a range finder, opening a feed inlet, adding pickling solution (4) to perform pickling chemical reaction, and opening the range finder in the whole process to monitor the outer diameters of a first monitoring area (35), a second monitoring area (36) and a third monitoring area (37) on the preform (3) in real time;
s3, removing the edge area of the cladding (33) of the preform (3) through acid washing and shaping to form a first corrosion area (34), turning the preform (3) 180 degrees through a clamp holder (2), and acid washing and shaping to form a second corrosion area (34);
s4, washing the preform (3), ultrasonically washing, washing off pickling solution (4) on the surface of the preform (3), placing the preform (3) on a bearing frame, and airing in a ventilation groove.
6. The method for acid cleaning and shaping of panda-type polarization maintaining optical fiber preform according to claim 5, wherein in step S2, the first monitoring area (35) is a head portion of the preform (3), the second monitoring area (36) is a middle portion of the preform (3), and the third monitoring area (37) is a tail portion of the preform (3).
7. The method for acid cleaning and shaping a panda-type polarization maintaining optical fiber preform according to claim 5, wherein the total time of acid cleaning in the step S3 is 23-28 hours.
8. The method for acid washing and shaping a panda-type polarization maintaining optical fiber preform according to claim 5, wherein the number of times of washing in step S4 is 3-5.
9. The method for acid cleaning and shaping a panda-type polarization maintaining optical fiber preform according to claim 5, wherein the ultrasonic cleaning time in the step S4 is 10-40min.
10. The method for acid cleaning and shaping a panda-type polarization maintaining optical fiber preform according to claim 5, wherein the time of air drying in the step S4 is 18-28h.
CN202311831795.6A 2023-12-28 2023-12-28 Acid washing shaping method and device for panda type polarization maintaining optical fiber preform Pending CN117700091A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202311831795.6A CN117700091A (en) 2023-12-28 2023-12-28 Acid washing shaping method and device for panda type polarization maintaining optical fiber preform

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202311831795.6A CN117700091A (en) 2023-12-28 2023-12-28 Acid washing shaping method and device for panda type polarization maintaining optical fiber preform

Publications (1)

Publication Number Publication Date
CN117700091A true CN117700091A (en) 2024-03-15

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Application Number Title Priority Date Filing Date
CN202311831795.6A Pending CN117700091A (en) 2023-12-28 2023-12-28 Acid washing shaping method and device for panda type polarization maintaining optical fiber preform

Country Status (1)

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