阅读说明：本技术 一种提高光纤预制棒参数均匀性的控制方法 (Control method for improving parameter uniformity of optical fiber preform ) 是由 顾金祥 庞耀 黄轩 周钰楠 李赵华 吴彬 王智俊 吴振伟 鲁阳 刘毅 戴石 梅 于 2020-11-24 设计创作，主要内容包括：本发明公开了一种提高光纤预制棒参数均匀性的控制方法,使用摄像头监控VAD法沉积过程,获取沉积过程中疏松体直径的实时趋势数据,获得包芯比、△、△-的波动数据,调控沉积原料、锗及四氟化碳流量。本发明提供的提高光纤预制棒参数均匀性的控制方法,使用两种控制方案,一是根据系统给定目标,二是根据实际测试值,控制器系统实时接收包芯比、△、△-参数波动数据并处理,实时调控气体流量,使得沉积过程中工艺参数得到更为精准的控制,在连续生产过程中,系统在大数据的作用下将实现每根芯棒数据的往复“训练”与“验证”,各沉积机台之间的数据共享使用、共同优化,提高工作效率和准确性,实现光纤预制棒参数的均匀、准确控制。(The invention discloses a control method for improving parameter uniformity of an optical fiber preform rod, which is characterized in that a camera is used for monitoring a deposition process of a VAD method, real-time trend data of the diameter of a loose body in the deposition process is obtained, fluctuation data of a core-spun ratio, delta and delta are obtained, and the flow of deposition raw materials, germanium and carbon tetrafluoride are regulated and controlled. The control method for improving the parameter uniformity of the optical fiber preform rod provided by the invention uses two control schemes, wherein firstly, according to a given target of the system and secondly according to an actual test value, the controller system receives and processes the core-spun ratio, the delta and the delta-parameter fluctuation data in real time, and regulates and controls the gas flow in real time, so that the process parameters in the deposition process are controlled more accurately, in the continuous production process, the system realizes the reciprocating 'training' and 'verification' of each core rod data under the action of big data, the data among all deposition machine tables are shared and jointly optimized, the working efficiency and the accuracy are improved, and the uniform and accurate control of the parameters of the optical fiber preform rod is realized.)

1. A control method for improving the parameter uniformity of an optical fiber preform is characterized by comprising the following steps:

producing an optical fiber preform by a VAD method, monitoring the deposition process of the VAD method by using a camera and uploading the deposition process to a controller system, acquiring real-time trend data of the diameter of a loose body in the deposition process, acquiring core-spun ratio fluctuation data, and adjusting the flow of deposition raw materials according to the core-spun ratio fluctuation data;

the controller system feeds back the core-spun ratio to deviate from a given target and adjusts the length of the loose body; at the moment, if the diameters of the cladding and the core layer fluctuate synchronously, the flow of the deposition raw materials is adjusted;

the controller system feeds back delta fluctuation data and adjusts germanium flow according to the delta fluctuation data; at the moment, if the diameter of the core layer fluctuates, the germanium flow needs to be synchronously adjusted;

the controller system feeds back delta-fluctuation data and adjusts the carbon tetrafluoride flow according to the delta-fluctuation data.

2. The method of claim 1, wherein the step of adjusting the flow rate of the deposition material according to the fluctuation data of the core-spun ratio comprises:

the core-spun ratio is changed according to a given target, the change is initiated by an engineer according to customer requirements, the engineer confirms that the core-spun ratio is updated and uploaded to a controller system, if the production length of the loose body is smaller than 100mm, the core-spun ratio of the previous loose body is fed back immediately, the flow of the deposition raw material is adjusted, and if the production length of the loose body is larger than 100mm, the next loose body is fed back, and the flow of the deposition raw material is adjusted.

3. The control method for improving the parameter uniformity of an optical fiber preform according to claim 2, wherein the adjustment of the flow rate of the deposition material is 0.3L when the fluctuation of the core-spun ratio is 0 to 0.1; when the core-spun ratio fluctuation is 0.1-0.2, the flow of the deposition raw material is adjusted to 0.6L; when the core-spun ratio fluctuation is 0.2-0.3, the flow of the deposition raw material is adjusted to 1.0L; when the core-spun ratio fluctuation is larger than 0.3, the flow of the deposition raw material is manually adjusted.

4. A control method for improving the uniformity of optical fiber preform parameters according to claim 1, wherein said bulk length is calculated according to the following formula:

d＝a×c/b

in the formula:

a is the production length, b is the extension length, c is the extension length to be adjusted, and d is the length of the loose body to be adjusted.

5. The method of claim 1, wherein the step of adjusting the flow rate of the deposition material if the diameters of the cladding and the core fluctuate synchronously comprises:

the fluctuation size of the diameter of the cladding is 5mm, the fluctuation size of the diameter of the core layer is 1mm, and the flow adjustment size of the deposition raw material is 0.3L; the fluctuation size of the diameter of the cladding is 10mm, the fluctuation size of the diameter of the core layer is 2mm, and the flow adjustment size of the deposition raw material is 0.6L; the fluctuation size of the diameter of the cladding is 15mm, the fluctuation size of the diameter of the core layer is 3mm, and the flow adjustment size of the deposition raw material is 1.0L; the diameter fluctuation size of the cladding is larger than 15mm, the diameter fluctuation size of the core layer is larger than 3mm, and the flow of the deposition raw material is manually adjusted.

6. The method of claim 1, wherein the step of adjusting the germanium flux based on the delta fluctuation data comprises:

the delta given target changes, the change is initiated by an engineer according to the customer requirement, the engineer confirms that the delta given target is updated and uploads the updated delta given target to the controller system, if the production length of the loose body is smaller than 100mm, feedback is immediately carried out according to the delta size of the previous loose body, the germanium flow rate is adjusted, and if the production length of the loose body is larger than 100mm, feedback is carried out on the next loose body, and the germanium flow rate is adjusted.

7. The control method for improving the parameter uniformity of an optical fiber preform according to claim 1, wherein the germanium flow is adjusted to 3mL when the size of the Δ fluctuation is 0-0.05; when the delta fluctuation is 0.05-0.1, the germanium flow is adjusted to be 6 mL; when the delta fluctuation is 0.1-0.15, the adjustment of the germanium flow is 10 mL; when the delta fluctuation is larger than 0.15, the germanium flow is manually adjusted.

8. The method of claim 1, wherein the delta-target is changed, the change is initiated by an engineer according to customer requirements, the engineer confirms the updated delta-target and uploads the updated delta-target to the controller system, if the loose body production length is less than 100mm, the delta-target is immediately fed back according to the previous loose body production length to adjust the carbon tetrafluoride flow, and if the loose body production length is greater than 100mm, the delta-target is fed back to the next loose body to adjust the carbon tetrafluoride flow.

9. The control method for improving the uniformity of optical fiber preform parameters of claim 1, wherein the adjustment of carbon tetrafluoride flow is 40mL when the delta-fluctuation is 0-0.00001; when the delta-fluctuation size is 0.00001-0.000015, the flow of the carbon tetrafluoride is adjusted to 80 mL; when the delta-fluctuation size is 0.000015-0.00002, the adjustment size of the carbon tetrafluoride flow is 120 mL; when the delta-fluctuation size is larger than 0.00002, the carbon tetrafluoride flow is manually adjusted.

Technical Field

The invention belongs to the technical field of optical fiber perform manufacturing, and particularly relates to a control method for improving parameter uniformity of an optical fiber perform.

Background

Chinese patent of the invention, publication No. CN105347667B, discloses a method and apparatus for controlling stability of optical parameters of an optical fiber preform, which improves the stability of the parameters of the optical fiber preform by optimizing the air intake and exhaust of a deposition cavity, but cannot know whether the parameter uniformity changes in the deposition process and cannot adjust the parameters in real time to improve the uniformity.

Currently, methods for manufacturing optical fiber preforms include VAD, OVD, MCVD, and PCVD, and among them, VAD is favored by many manufacturers because of its advantages such as high deposition efficiency and low cost. The VAD method is used for manufacturing optical fiber preforms, parameters in the rod fluctuate, and the uniformity of the parameters in the rod is generally optimized through parameter segmentation (mainstream companies such as Hengtong, Futong, Corning, Zhongtian, Changfei and the like). The parameter uniformity of the optical fiber preform is controlled by waiting for a test result by a technical engineer, generally requiring 24 hours or more, adjusting the deposition process parameters according to the test result, and waiting for the test result if the adjusted parameters are in place. Due to the existence of long-time hysteresis and dependence on technicians, for example, no technician adjusts parameters in night shifts or holidays, but the production line still keeps normal operation, so that batch core rod parameter nonuniformity is easily caused during batch production, and the core of the optical fiber is an optical fiber preform, so that the optical fiber product has abnormity such as cut-off wavelength, zero dispersion, attenuation and the like due to the nonuniform core rod parameter, so that not only great quality hidden dangers exist, but also client complaints are easily caused, and especially loss caused by the manufacture of optical cable finished products or products buried underground is immeasurable.

Because the cavity temperature is higher, thermal-insulated protection need be considered in the camera during operation, avoids the camera to be in the data distortion that leads to acquireing under the high temperature for a long time.

Disclosure of Invention

In order to solve the technical problems in the prior art, the invention aims to provide a control method for improving the parameter uniformity of an optical fiber preform.

In order to achieve the purpose and achieve the technical effect, the invention adopts the technical scheme that:

a control method for improving the parameter uniformity of an optical fiber preform comprises the following steps:

producing an optical fiber preform by a VAD method, monitoring the deposition process of the VAD method by using a camera and uploading the deposition process to a controller system, acquiring real-time trend data of the diameter of a loose body in the deposition process, acquiring core-spun ratio fluctuation data, and adjusting the flow of deposition raw materials according to the core-spun ratio fluctuation data;

the controller system feeds back the core-spun ratio to deviate from a given target and adjusts the length of the loose body; at the moment, if the diameters of the cladding and the core layer fluctuate synchronously, the flow of the deposition raw materials is adjusted;

the controller system feeds back delta fluctuation data and adjusts germanium flow according to the delta fluctuation data; at the moment, if the diameter of the core layer fluctuates, the germanium flow needs to be synchronously adjusted;

the controller system feeds back delta-fluctuation data and adjusts the carbon tetrafluoride flow according to the delta-fluctuation data.

Further, the step of adjusting the flow of the deposition raw material according to the core-spun ratio fluctuation data comprises the following steps:

the core-spun ratio is changed according to a given target, the change is initiated by an engineer according to customer requirements, the engineer confirms that the core-spun ratio is updated and uploaded to a controller system, if the production length of the loose body is smaller than 100mm, the core-spun ratio of the previous loose body is fed back immediately, the flow of the deposition raw material is adjusted, and if the production length of the loose body is larger than 100mm, the next loose body is fed back, and the flow of the deposition raw material is adjusted.

Further, when the core-spun ratio fluctuation is 0-0.1, the flow of the deposition raw material is adjusted to 0.3L; when the core-spun ratio fluctuation is 0.1-0.2, the flow of the deposition raw material is adjusted to 0.6L; when the core-spun ratio fluctuation is 0.2-0.3, the flow of the deposition raw material is adjusted to 1.0L; when the core-spun ratio fluctuation is larger than 0.3, the flow of the deposition raw material is manually adjusted.

Further, the loose body length is calculated according to the following formula:

d＝a×c/b

in the formula:

a is the production length, b is the extension length, c is the extension length to be adjusted, and d is the length of the loose body to be adjusted.

Further, if the diameter of the cladding layer and the diameter of the core layer fluctuate synchronously, the step of adjusting the flow of the deposition raw material comprises the following steps:

the fluctuation size of the diameter of the cladding is 5mm, the fluctuation size of the diameter of the core layer is 1mm, and the flow adjustment size of the deposition raw material is 0.3L; the fluctuation size of the diameter of the cladding is 10mm, the fluctuation size of the diameter of the core layer is 2mm, and the flow adjustment size of the deposition raw material is 0.6L; the fluctuation size of the diameter of the cladding is 15mm, the fluctuation size of the diameter of the core layer is 3mm, and the flow adjustment size of the deposition raw material is 1.0L; the diameter fluctuation size of the cladding is larger than 15mm, the diameter fluctuation size of the core layer is larger than 3mm, and the flow of the deposition raw material is manually adjusted.

Further, the step of adjusting the germanium flow rate according to the delta fluctuation data comprises:

the delta given target changes, the change is initiated by an engineer according to the customer requirement, the engineer confirms that the delta given target is updated and uploads the updated delta given target to the controller system, if the production length of the loose body is smaller than 100mm, feedback is immediately carried out according to the delta size of the previous loose body, the germanium flow rate is adjusted, and if the production length of the loose body is larger than 100mm, feedback is carried out on the next loose body, and the germanium flow rate is adjusted.

Further, when the delta fluctuation is 0-0.05, the adjustment of the germanium flow is 3 mL; when the delta fluctuation is 0.05-0.1, the germanium flow is adjusted to be 6 mL; when the delta fluctuation is 0.1-0.15, the adjustment of the germanium flow is 10 mL; when the delta fluctuation is larger than 0.15, the germanium flow is manually adjusted.

Further, the delta-given target is changed, the change is initiated by an engineer according to the customer requirement, the engineer confirms and updates the delta-given target and uploads the delta-given target to the controller system, if the production length of the loose body is smaller than 100mm, feedback is immediately carried out according to the delta-size of the previous loose body, the carbon tetrafluoride flow rate is adjusted, and if the production length of the loose body is larger than 100mm, feedback is carried out on the next loose body, and the carbon tetrafluoride flow rate is adjusted.

Further, when the delta-fluctuation size is 0-0.00001, the adjustment size of the carbon tetrafluoride flow is 40 mL; when the delta-fluctuation size is 0.00001-0.000015, the flow of the carbon tetrafluoride is adjusted to 80 mL; when the delta-fluctuation size is 0.000015-0.00002, the adjustment size of the carbon tetrafluoride flow is 120 mL; when the delta-fluctuation size is larger than 0.00002, the carbon tetrafluoride flow is manually adjusted.

Compared with the prior art, the invention has the beneficial effects that:

the invention discloses a control method for improving parameter uniformity of an optical fiber preform rod, which is characterized in that a camera is used for monitoring a deposition process of a VAD method, real-time trend data of the diameter of a loose body in the deposition process is obtained, fluctuation data of a core-spun ratio, delta and delta are obtained, and the flow of deposition raw materials, the flow of germanium and the flow of carbon tetrafluoride are regulated and controlled. The control method for improving the parameter uniformity of the optical fiber preform rod provided by the invention uses two control schemes, wherein firstly, according to a given target of the system and secondly according to an actual test value, the controller system receives and processes the core-spun ratio, the delta and the delta-parameter fluctuation data in real time, and regulates and controls the flow of the deposition raw material, the flow of germanium and the flow of carbon tetrafluoride in real time, so that the process parameters in the deposition process are controlled more accurately, meanwhile, in the continuous production process, the system realizes the reciprocating training and verification of each core rod data under the action of big data, and the data among all deposition machine tables are shared, used and optimized together, so that the working efficiency and the accuracy are improved, and the uniform and accurate control of the optical fiber preform rod parameters is realized.

Detailed Description

The present invention is described in detail below so that the advantages and features of the present invention can be more easily understood by those skilled in the art, and thus the scope of the present invention can be clearly and clearly defined.

The noun explains:

core-spun ratio: the ratio of the diameter of the cladding to the diameter of the core of the optical fiber preform;

and (delta): the refractive index of the core layer;

and (delta-): the refractive index of the cladding;

a control method for improving the uniformity of parameters of an optical fiber preform rod is characterized in that the control parameters mainly comprise three parameters of a core-spun ratio, a core layer refractive index delta and a cladding layer refractive index delta, and any one parameter has two control schemes, wherein the scheme is to give a target according to each parameter for response and feedback, the scheme is to monitor each parameter data in real time by using an Arnold PK2600 refractive index test device in the existing product to obtain test values (the core-spun ratio, the refractive index and the like of a core rod) for response and feedback, and the two control schemes of the three parameters are specifically introduced below.

1) Corespun ratio parameter control

The first scheme is as follows: the core-spun ratio given by the system changes according to a given target, the change is initiated by an engineer according to customer requirements, the engineer confirms that the core-spun ratio given target is updated and uploads the core-spun ratio given target to the controller system, at the moment, the controller system of the deposition machine receives a core-spun ratio change signal, if the production length of the loose body is less than 100mm, feedback is immediately carried out according to the core-spun ratio of the previous loose body, the flow of the deposition raw material is adjusted through the mass flow meter MFC, and the adjustment rule is shown in the following table 1.

TABLE 1

And if the production length of the loose body is more than 100mm, feeding back the next loose body, and adjusting the flow of the deposition raw material according to the same rule.

Scheme II: the core-spun ratio data of real-time monitoring to upload to the controller system, the controller system compares real-time core-spun ratio test data and core-spun ratio given target, feeds back the core-spun ratio and deviates from the given target, the data of giving the deposit board controller system this moment is extension plug test data set, the system matches production length adjustment deposit raw materials flow, the loose length position formula that needs the adjustment is:

d＝a×c/b

in the formula: a is the production length, b is the extension length, c is the extension length to be adjusted, d is the length of the loose body to be adjusted, and the adjustment rule is the same as the above table 1.

Meanwhile, when the diameter fluctuation is caused by non-repetition of the deposition process (i.e., the diameter of the cladding or the core tested for 10min continuously deviates from the upper diameter in the case of not actively modifying the parameters), the simultaneous adjustment is required, the adjustment scheme is as shown in table 2 below, and if the cladding and the core fluctuate synchronously, the cumulative adjustment is required.

TABLE 2

2) Delta parameter control

The first scheme is as follows: the core layer refractive index delta given target given by the system changes, the change is initiated by an engineer according to the customer requirement, the engineer confirms to update the delta given target, at the moment, a controller system of a deposition machine receives a delta change signal, if the production length is less than 100mm, feedback is immediately carried out, the germanium flow is adjusted through a mass flow meter MFC, namely adjustment is carried out according to the previous delta size, and the adjustment rule is shown in the following table 3.

TABLE 3

If the production length is greater than 100mm, the next adjustment is made, with the same rules as in table 3 above.

Scheme II: and monitoring the refractive index delta data of the core layer in real time, uploading the refractive index delta data to a controller system, comparing the real-time delta data with a given delta target by the controller system, feeding back the real-time delta deviating from the given target, providing an extended core rod test data set to the machine table controller system, adjusting the germanium flow rate by matching the production length of the system, and adjusting the rule as the rule in the table 3. Meanwhile, when the deposition process does not repeatedly cause diameter fluctuation (i.e., the diameter of the core layer tested for 10min continuously deviates from the upper root without actively modifying the parameters), the simultaneous adjustment is required, and the adjustment scheme is as shown in table 4 below.

TABLE 4

3) Delta-parameter control

The first scheme is as follows: the delta-target given by the system is changed, the change is initiated by an engineer according to the customer requirement, the engineer confirms to update the delta-target given, the controller system of the deposition machine receives the delta-change signal at the moment, if the production length is less than 100mm, the feedback is immediately carried out, the MFC is used for adjusting the carbon tetrafluoride flow rate through the quality control meter, namely, the adjustment is carried out according to the previous delta-size, and the adjustment rule is shown in the following table 5.

TABLE 5

If the production length is greater than 100mm, the next adjustment is made, with the same rules as in table 5 above.

Scheme II: and (3) monitoring the delta-data in real time and uploading the delta-data to a controller system, comparing the real-time delta-data with a delta-given target by the controller system, feeding back the delta-deviation given target, sending a data set for testing an extended core rod to a deposition machine at the moment, matching the production length by the system to adjust the carbon tetrafluoride flow, and adjusting the rule as shown in the table 5.

The parts of the invention not specifically described can be realized by adopting the prior art, and the details are not described herein.

The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by the present specification, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.