WO2020232782A1

WO2020232782A1 - Non-contact optical fiber surface tension loading measurement device and measurement method

Info

Publication number: WO2020232782A1
Application number: PCT/CN2019/091645
Authority: WO
Inventors: 刘恺; 何兵; 周军; 张海波; 杨依枫; 陈晓龙
Original assignee: 中国科学院上海光学精密机械研究所
Priority date: 2019-05-21
Filing date: 2019-06-18
Publication date: 2020-11-26
Also published as: CN110160677B; CN110160677A

Abstract

Disclosed are a non-contact optical fiber surface tension loading measurement device and measurement method. The device comprises a left optical fiber clamp (1), a right optical fiber clamp (2), a left optical fiber pressing block (3), a right optical fiber pressing block (4), a tension transmission mechanism (5), a rigid connection rod (6), a tension sensor (7), a tension measurement and control unit (8), a left bottom plate (9) and a linear displacement table (10). According to the device and the method, real-time changes in the surface tension of an optical fiber can be rapidly sensed, and the surface tension of the optical fiber can be precisely measured; meanwhile, whether the optical fiber (11) is bent or stretched can be indicated by means of a value obtained by calculation; according to the parameters, the movement of the linear displacement table (10) may be used to stretch or compress the surface tension of the optical fiber, and the surface tension of the optical fiber is controlled and kept balanced, and this has an important application value for device preparation of the optical fiber (11), an optical fiber beam combiner, a splitter and the like. The present invention has an important application value for loading specified tensions during the preparation of high-power optical fiber devices.

Description

Non-contact optical fiber surface tension loading measuring device and measuring method

Technical field

The present invention relates to an optical fiber, in particular to a non-contact optical fiber surface tension loading measurement device and a measurement method. It relates to loading suitable tension required for optical fiber cutting, real-time monitoring of surface tension when optical fiber is tapered, and removing high-power optical fiber passive components. Stress packaging technology.

Background technique

With the development of laser application technology, the fields of space communications, laser weapons, material processing, remote sensing and lidar have put forward an urgent demand for high-power, high-beam quality lasers. Fiber laser has the characteristics of compact structure, convenient thermal management, good beam quality and high conversion efficiency, and has been widely used in the field of high-power lasers.

Fiber passive components are one of the core components in fiber oscillators and fiber laser amplifiers. The preparation of optical fiber passive devices usually involves optical fiber cutting, optical fiber tapering, and stress-relieving packaging technology for high-power passive devices. Since it is necessary to ensure the integrity of the surface coating of the optical fiber, this type of tension measuring device is preferably non-contact. The existing tension measurement device is a contact measurement, and the contact measurement is easily contaminated by contact objects and dust. Therefore, how to realize non-contact optical fiber surface tension measurement is a technical problem to be solved.

Summary of the invention

The purpose of the present invention is to provide a non-contact optical fiber surface tension loading measurement device and measurement method. The device can solve the pollution-free key problem that the optical fiber bundle needs to be drawn uniformly during the preparation process of the optical fiber device, so as to improve the preparation efficiency and success rate of the optical fiber device. Therefore, the present invention is of great significance to the preparation of optical fiber devices such as optical fiber combiners and splitters.

The technical solution of the present invention is as follows

A non-contact optical fiber surface tension measurement device, which is characterized in that it includes a left optical fiber clamp, a right optical fiber clamp, a left optical fiber clamp, a right optical fiber clamp, a tension transmission mechanism, a rigid connecting rod, a tension sensor, a tension measurement and control unit, The relationship between the components of the left base plate and the linear stage is as follows:

The bottom of the left optical fiber clamp is fixed on the left bottom plate; the bottom of the tension sensor is rigidly connected with the upper surface of the linear displacement platform, and the tension transmission mechanism is composed of a sliding seat, a sliding rail and the other The upper surface of the sliding seat is fixed with the right optical fiber clamp and rigidly connected with the tension sensor through a rigid connecting rod. The sliding rail is fixed on the linear moving platform, so The bottom of the right fiber clamp forms a sliding connection with the linear translation stage through a tension transmission mechanism; the output end of the tension sensor is connected to the input end of the tension measurement and control unit, and the output end of the tension measurement and control unit is connected to the The drive control end of the linear moving platform is connected, the V-shaped groove of the left fiber clamp and the V-shaped groove of the right fiber clamp are located on the same center line. During the test, the fiber to be tested is placed on the left fiber clamp and In the V-shaped groove of the right fiber clamp, they are respectively fixed by the left fiber clamp and the right fiber clamp.

The size of the V-shaped groove has an adjustment mechanism.

The axis of the rigid connecting rod is parallel to the axis of the optical fiber to be tested.

The friction coefficient between the sliding seat and the sliding rail in the tension transmission mechanism is in the range of 0.0006 to 0.0012.

The optical fiber tension measurement method using the above non-contact optical fiber surface tension loading measurement device is characterized in that the method includes the following steps:

1) Place the two ends of the fiber to be tested in the V-shaped grooves of the left fiber clamp and the right fiber clamp, and fix them with the left fiber clamp and the right fiber clamp. Adjust the left fiber clamp and the right fiber The V-groove of the fixture is on the same centerline with the fiber to be tested;

2) The tension measurement and control unit outputs a drive signal to the linear movement platform to drive the linear movement platform to move, and the tension sensor inputs the measured tension F _t into the tension measurement and control unit, In the tension measurement and control unit, the friction force of the rolling unit composed of the right fiber clamp and the right fiber clamp is stored in advance as F _s =μ*mg; where μ is the friction coefficient of the rolling unit, and m is the right fiber clamp and The sum of the masses of the rolling unit formed by the right fiber press block, g is the acceleration of gravity;

3) The tension measurement and control unit calculates the true tension F on the surface of the optical fiber according to the following formula:

F=F _t -F _s ,

4) When F does not reach the target value, the tension measurement and control unit adjusts the drive signal to the linear moving platform until F reaches the target value, stop driving, and inform the next step;

5) Operate according to work needs.

Technical effects of the present invention:

The non-contact optical fiber surface tension measurement device of the present invention can quickly sense the real-time change of the surface tension of the optical fiber, and can accurately measure the tension on the surface of the optical fiber. At the same time, the calculated value can reflect whether the optical fiber is bent or pulled. With these parameters, the surface tension of the optical fiber can be stretched or compressed by moving the linear stage to control the surface tension of the optical fiber and maintain a balance. When the fiber cone is prepared, it can effectively prevent the smooth stretching and compression of the fiber surface, and avoid cracks when the fiber is stretched at extreme speed; while the fiber is cut, it is necessary to monitor and apply the target fiber tension in real time to achieve a small angle without damage Fiber cutting to reduce splice loss. Therefore, the device of the present invention can have important application value for the preparation of optical fibers, optical fiber combiners, splitters and other devices.

Description of the drawings

Figure 1 is a schematic diagram of the non-contact optical fiber surface tension loading and testing device of the present invention.

Figure 2 is a schematic diagram of the three-dimensional fiber to be tested and its clamping structure.

Figure 3 is a schematic diagram of the structure of the rolling unit.

Figure 4 is a schematic diagram of the application of optical fiber tapering based on the tension measurement and control device.

Figure 5 is a schematic diagram of the application of fiber cutting based on the tension measurement and control device.

Figure 6 shows the tension measurement curve.

Detailed ways

Hereinafter, the present invention will be further explained with reference to the accompanying drawings and embodiments, but the protection scope of the present invention should not be limited by this.

The schematic diagram of the non-contact optical fiber surface tension loading and testing device of the present invention is shown in FIG. 1. It can be seen from the figure that the non-contact optical fiber surface tension measurement device of the present invention includes left optical fiber clamp 1, right optical fiber clamp 2, left optical fiber clamp 3, right optical fiber clamp 4, tension transmission mechanism 5, rigid connecting rod 6, tension The sensor 7, the tension measurement and control unit 8, the left bottom plate 9 and the linear translation stage 10 are composed of, and the relationship between the components is as follows:

The bottom of the left optical fiber clamp 1 is fixed on the left bottom plate 9; the bottom of the tension sensor 7 is rigidly connected to the upper surface of the linear displacement platform 10, and the tension transmission mechanism 5 is composed of a sliding seat 5. -1 and the sliding rail 5-3 and the ball 5-2 between them. The upper surface of the sliding seat 5-1 is fixed to the bottom surface of the right optical fiber clamp 2, and the right optical fiber clamp 2 passes The rigid connecting rod 6 is rigidly connected to the tension sensor 7, the slide rail 5-3 is fixed on the linear movement platform 10, and the bottom of the right fiber clamp 2 is connected to the linear translation stage via the tension transmission mechanism 5 10 constitutes a sliding connection; the output end of the tension sensor 7 is connected to the input end of the tension measurement and control unit 8, and the control output end of the tension measurement and control unit 8 is connected to the drive end of the linear movement platform 10 Connected, the V-shaped groove of the left optical fiber clamp 1 and the V-shaped groove of the right optical fiber clamp 2 are located on the same center line. During the test, the optical fiber 11 to be tested is placed in the left optical fiber clamp 1 and the right optical fiber clamp 2 respectively. Inside the V-shaped groove, and are respectively fixed by the left optical fiber clamp 3 and the right optical fiber clamp 4.

The optical fibers 11 to be tested are placed in the left fiber clamp 1 and the right fiber clamp 2 respectively, and are respectively fixed by the left fiber clamp 3 and the right fiber clamp 4 of the soft material on the upper part to ensure that the surface coating of the fiber is not scratched. hurt. Under the control of the tension measurement and control unit 8, the surface of the optical fiber is loaded with tension through the moving linear moving platform 10. The front part of the tension sensor 7 is connected to the right end of the right optical fiber clamp 2 through a rigid connecting rod 6, and the tension of the optical fiber 11 is indirectly measured through the tension transmission mechanism 5. The tension measurement and control unit 8 reads the measurement value of the tension sensor 7 in real time, and calculates and displays the real-time tension value of the optical fiber 11 to be tested according to the optical fiber tension calculation method. The tension measurement and control unit 8 can drive the linear displacement stage 5 to apply the target tension value to the optical fiber 14.

The left optical fiber clamp 1 and the right optical fiber clamp 2 adopt a V-shaped groove holding structure, and the V-shaped grooves in the left and right clamps are installed on the same center line to avoid the generation of other components of the force and increase the system measurement error.

The V-shaped groove has an adjusting mechanism for the size of the V-shaped groove, and commonly used different fiber diameters (such as 60, 125, 250, 400, 600 microns) are fixed by changing the size of the V-shaped groove. You can also change the size of the V-groove to measure N×1 fiber bundles, including N=2,3,4,5,6,7,...,19 and other common fiber combiner arrangements.

The axis of the rigid connecting rod 6 is parallel to the axis of the optical fiber 11 to be tested, so as to ensure the accuracy of the tension sensor 7 to measure the tension.

The friction coefficient between the sliding seat 5-1 and the sliding rail 5-2 of the tension transmission mechanism 5 is extremely small. The sliding seat 5-1 and the sliding rail 5-2 are on the stainless steel raceway through the steel ball 5-3. For rolling motion, the friction coefficient is in the range of 0.0006 to 0.0012.

Using the above non-contact optical fiber surface tension loading measurement device to perform an optical fiber tension measurement method, the method includes the following steps:

1) Place the two ends of the optical fiber 11 to be tested in the V-shaped grooves of the left fiber clamp 1 and the right fiber clamp 2, and fix them with the left fiber clamp 3 and the right fiber clamp 4, and adjust the left side The V-shaped groove of the optical fiber clamp 1, the right optical fiber clamp 2 and the optical fiber 11 to be tested are on the same centerline;

2) The tension measurement and control unit 8 outputs a drive signal to the linear movement platform 10 to drive the linear movement platform 10 to move, and the tension sensor 6 inputs the measured tension F _t into the The tension measurement and control unit 8, in which the friction force of the rolling unit composed of the right optical fiber clamp 2 and the right optical fiber clamp 4 is stored in advance is F _s = μ*mg; where μ is the friction of the rolling unit Coefficient, m is the sum of the mass of the rolling unit formed by the right fiber clamp 2 and the right fiber clamp 4, and g is the acceleration due to gravity;

3) The tension measurement and control unit 8 calculates the true tension F on the surface of the optical fiber 11 according to the following formula:

F=F _t -F _s ,

4) When F does not reach the target value, the tension measurement and control unit (8) adjusts the driving signal to the linear moving platform (10) until F reaches the target value, stop driving, and inform the next step;

5) Operate according to work needs.

The fiber to be tested can be a single fiber, as shown in Figure 1. It can be a three-dimensional fiber bundle, as shown in Figure 3.

As shown in Figure 4, in the production of optical fiber mode field adapters or optical fiber couplers and other devices, the optical fiber or optical fiber bundle needs to be tapered. In this application case, the optical fiber (11) needs to be placed flat on the left side. The optical fiber clamp 1 and the right optical fiber clamp 2 are fixed by the left optical fiber clamp 3 and the right optical fiber clamp 4 respectively. Use hydrogen-oxygen flame, electrode discharge, graphite ring or carbon dioxide laser to heat the optical fiber or optical fiber bundle at the target position to a molten state, and move the linear translation stage 10 during the heating process to apply tension to the optical fiber 11 according to the target taper. Stretching is performed, and the applied tension is measured by the tension sensor 7, and displayed and monitored by the tension measurement and control unit 8. The tension curve is shown in FIG. 6. Through the process of tapering the optical fiber, the tension measurement and control unit 8 feedbacks the linear translation stage 10 to apply appropriate dynamic tension to the optical fiber 11, thereby effectively controlling the length and taper of the tapered area, and finally effectively ensuring the coupling efficiency of the optical fiber device.

As shown in Figure 5, the optical fiber needs to be cut before fusion splicing, and the cutting angle of the optical fiber seriously affects the melting point quality. Excessive cutting angle will result in insufficient melting point strength and high splicing loss. The present invention can be applied to small-angle cutting applications of optical fibers or optical fiber bundles. Generally, the fusion splicing of optical fibers requires a small angle of the end face of the optical fiber, and the optical fiber 11 needs to be placed flat on the left optical fiber clamp 1 and the right optical fiber clamp 2 , And fixed with the left optical fiber clamp 3 and the right optical fiber clamp 4 respectively. According to the cladding diameter of the optical fiber 11 to be cut, the linear translation stage 10 is moved to apply tension to the optical fiber 11 for stretching, and the applied tension is measured by the tension sensor 7, and the tension measurement and control unit 8 Perform display and monitoring. When the tension of the optical fiber 11 reaches the target value, the optical fiber 11 is cut by the cleaver 14, which can effectively control the cutting angle of the optical fiber, thereby effectively ensuring the quality of the optical fiber fusion splicing. Before the fiber is cut, the fiber to be cut can be rotated, stretched and cut to achieve the cutting of the target fiber end cap angle.

In the packaging process of optical fiber devices, especially in optical fiber sensing applications, the stress of optical fiber devices needs to be strictly controlled, and the device is used to effectively monitor and control the packaging stress of optical fibers and optical fiber devices.

Claims

A non-contact optical fiber surface tension loading measurement device, which is characterized in that the device includes a left optical fiber clamp (1), a right optical fiber clamp (2), a left optical fiber clamp (3), a right optical fiber clamp (4), and tension Transmission mechanism (5), rigid connecting rod (6), tension sensor (7), tension measurement and control unit (8), left bottom plate (9) and linear translation stage (10);

The bottom of the left optical fiber clamp (1) is fixed on the left bottom plate (9); the bottom of the tension sensor (7) is rigidly connected to the upper surface of the linear displacement platform (10), and the The tension transmission mechanism (5) is composed of a sliding seat (5-1) and a sliding rail (5-3) and balls (5-2) between them. The upper surface of the sliding seat (5-1) is The right optical fiber clamp (2) is fixed and rigidly connected with the tension sensor (7) through a rigid connecting rod (6), and the slide rail (5-3) is fixed on the linear moving platform (10) Above, the bottom of the right optical fiber clamp (2) forms a sliding connection with the linear translation stage (10) through the tension transmission mechanism (5); the output end of the tension sensor (7) and the tension measurement and control unit ( 8) is connected to the input end, the output end of the tension measurement and control unit (8) is connected to the drive control end of the linear moving platform (10), the V-shaped groove of the left optical fiber clamp (1) and The V-groove of the right fiber clamp (2) is located on the same center line. During the test, the fiber to be tested (11) is placed in the V-groove of the left fiber clamp (1) and the right fiber clamp (2) respectively. It is fixed by the left optical fiber clamp (3) and the right optical fiber clamp (4).
The non-contact optical fiber surface tension measurement device according to claim 1, wherein the size of the V-shaped groove has an adjusting mechanism.
The non-contact optical fiber surface tension measurement device according to claim 1, wherein the axis of the rigid connecting rod (6) is parallel to the axis of the optical fiber (11) to be tested.
The non-contact optical fiber surface tension measurement device according to claim 1, wherein the friction coefficient between the sliding seat (5-1) and the sliding rail (5-2) of the tension transmission mechanism (5) In the range of 0.0006 to 0.0012.
A method for measuring optical fiber tension using the non-contact optical fiber surface tension measurement device according to claim 1, wherein the method includes the following steps:

1) Place both ends of the fiber to be tested (11) in the V-shaped grooves of the left fiber clamp (1) and right fiber clamp (2), and pass the left fiber clamp (3) and the right fiber clamp ( 4) Fix and adjust the V-groove of the left optical fiber clamp (1) and right optical fiber clamp (2) to be the same centerline with the optical fiber to be tested (11);

2) The tension measurement and control unit (8) outputs a drive signal to the linear movement platform (10) to drive the linear movement platform (10) to move, and the tension sensor (6) will measure the corresponding The tension F t is input into the tension measurement and control unit (8), and the friction force of the rolling unit composed of the right fiber clamp (2) and the right fiber clamp (4) is stored in the tension measurement and control unit (8) in advance Is F s = μ*mg; where μ is the friction coefficient of the rolling unit, m is the sum of the mass of the rolling unit formed by the right fiber clamp (2) and the right fiber clamp (4), and g is the acceleration of gravity;

3) The tension measurement and control unit (8) calculates the true tension F on the surface of the optical fiber (11) according to the following formula:

F=F t -F s ,

4) When F does not reach the target value, the tension measurement and control unit (8) adjusts the driving signal to the linear moving platform (10) until F reaches the target value, stop driving, and inform the next step;

5) Operate according to work needs.