Optical fiber laser module beam na testing device

Abstract

The application relates to the technical field of optical fiber testing, in particular to a fiber laser module light beam NA testing device which comprises a laser and a laser power meter opposite to the laser, a light shield plate slidably connected between the laser and the laser power meter, a guide rail arranged between the laser and the laser power meter, the light shield plate being slidably connected in the guide rail, a cooling pipeline arranged in the light shield plate, the cooling pipeline being filled with cooling liquid, a cooling fan arranged below the light shield plate, the cooling pipeline comprising a cooling pipe opposite to the cooling fan and a heat absorption pipe arranged in the light shield plate, and the cooling pipe and the heat absorption pipe being connected through a return pipe. In the LIV measurement system of the fiber module, the light shield plate is additionally arranged, the original LIV testing device and layout are not changed, the light shield plate is integrated into the LIV testing device, the cost is reduced, the space is reduced, the testing function is improved, and the light shield plate is compatible with the light emission measurement of optical fibers of various specifications and sizes. The algorithm used is a simple trigonometric function calculation.

Description

Technical Field

[0001] This application relates to the technical field of fiber optic testing, and in particular to a device for testing the NA (non-reflective) beam of a fiber laser module. Background Technology

[0002] For measuring the beam NA of an optical fiber module, a common measurement device is the beam spot measurement device. This device is built according to the CCD measurement method (GB / T 15175-2012) and requires an optical lens, a CCD camera, and an imaging screen. This device needs to integrate an optical system and a visual imaging algorithm.

[0003] Both hardware development and software algorithm costs are high; the space required to build the optical path is large, and the testing function is limited; the size and energy of the beam need to be considered when selecting appropriate hardware; the CCD measurement method cannot detect the absolute energy of the beam, making it difficult to screen out products that do not meet the energy requirements. Summary of the Invention

[0004] To facilitate beam energy screening, this application provides a fiber laser module beam NA testing device.

[0005] The fiber laser module beam NA testing device provided in this application adopts the following technical solution: A fiber laser module beam NA testing device includes a laser and a laser power meter facing the laser, and a light shield slidably connected between the laser and the laser power meter. The sliding direction of the light shield is perpendicular to the emission direction of the laser. It also includes a guide rail disposed between the laser and the laser power meter, with the light shield slidably connected within the guide rail. A cooling pipe filled with coolant is provided inside the light shield. A cooling fan is located below the light shield. The cooling pipe includes a cooling pipe facing the cooling fan and a heat-absorbing pipe located inside the light shield. The cooling pipe and the heat-absorbing pipe are connected by a return water pipe.

[0006] By adopting the above technical solution, a light-shielding plate is added to the LIV measurement system of the fiber optic module. Without changing the original LIV test device and layout, it is integrated into the system, reducing costs, shrinking space, and improving and increasing test functions. It is also compatible with the measurement of light output from fibers of various sizes and specifications. The algorithm used is a simple trigonometric function calculation. We can directly obtain the absolute energy of the fiber output light from the LIV system, ensuring that the beam energy meets specifications before performing NA measurement. During the movement of the light-shielding plate, part of the beam is gradually blocked, causing the light intensity to gradually decrease. After blocking the light, the temperature of the light-shielding plate itself increases. Cooling pipes and coolant cool the light-shielding plate, and a cooling fan dissipates the heat. When the tail end of the light-shielding plate passes the center point of the laser power meter, as the light-shielding plate continues to move, it gradually moves away from the beam area, and the light intensity gradually increases again until the light-shielding plate is completely away from the beam area. That is, during the movement of the light-shielding plate, the light intensity received by the laser power meter should be symmetrical. Let the vertical distance between the light-shielding plate and the laser be d, and the light intensity of the beam of the desired energy to be tested will have two points on the laser power meter. Let the distance between the two points be 2x. Then the NA value of this beam is... .

[0007] Preferably, the guide rail is provided with a rack, and a traveling gear that meshes with the rack is rotatably connected below the light shield. The traveling gear is connected to a drive motor via a pulley.

[0008] By adopting the above technical solution, the drive motor drives the walking gear to rotate, and the walking gear rotates along the rack, thereby moving along the guide rail and controlling stability.

[0009] Preferably, the end of the return water pipe near the cooling pipe is rotatably connected to a centrifugal wheel for driving the coolant to flow from the return water pipe to the heat absorption pipe, and the end of the heat absorption pipe near the cooling pipe is rotatably connected to a return water wheel for driving the coolant to flow from the heat absorption pipe to the cooling pipe.

[0010] By adopting the above technical solution, the centrifugal impeller and the return impeller provide power for the flow of coolant, thereby improving the cooling effect.

[0011] Preferably, the output shaft of the drive motor and the pulley are connected by a transmission shaft. The two ends of the transmission shaft are slidably connected to the output shaft of the drive motor and the pulley by splines, respectively. A large transmission gear and a small transmission gear are coaxially fixed on the transmission shaft. The centrifugal wheel is coaxially provided with a centrifugal shaft. A large centrifugal gear and a small centrifugal gear are coaxially fixed on the centrifugal shaft. The large centrifugal gear and the small transmission gear are meshed, and the small centrifugal gear and the large transmission gear are centrifugally meshed. The distance between the large transmission gear and the small transmission gear is equal to the distance between the large centrifugal gear and the small centrifugal gear, and is greater than the thickness of the large centrifugal gear, the small centrifugal gear, the large transmission gear, and the small transmission gear.

[0012] By adopting the above technical solution, when the drive motor starts, its output drives the transmission shaft, which in turn drives the traveling gear, thus moving the light-shielding plate. Simultaneously, as the transmission shaft rotates, the large and small transmission gears rotate synchronously. When the light-shielding plate is far from the light beam, it has not yet received light and its temperature is low. At this time, the small transmission gear and the large centrifugal gear mesh, and the transmission shaft drives the centrifugal shaft to rotate, but the centrifugal shaft rotates at a relatively slow speed. However, when the light-shielding plate is in the illuminated area, its temperature is higher. At this time, the large transmission gear and the small centrifugal gear mesh, and the transmission shaft drives the centrifugal shaft to rotate at high speed, thereby accelerating the rotation of the centrifugal wheel, increasing the flow rate of the coolant, and improving the cooling effect. Through the arrangement of the transmission shaft and centrifugal shaft, the drive motor can drive the centrifugal wheel to rotate without the need for an additional power mechanism, making it convenient to use and reducing the weight of the device.

[0013] Preferably, the return water impeller is coaxially connected to a return water shaft, and the return water shaft and the centrifugal shaft are connected by a synchronous belt.

[0014] By adopting the above technical solution, the return water wheel is connected to the centrifugal wheel via a synchronous belt, and the two rotate synchronously, further accelerating the flow of coolant.

[0015] Preferably, the guide rail includes a detection section facing the laser power meter and running sections located at both ends of the detection section. The two ends of the detection section are provided with magnetic blocks of opposite polarity. The axis of the magnetic blocks is parallel to the axis of the pulley. The end of the drive shaft near the pulley is provided with a magnetic element.

[0016] By adopting the above technical solution, the irradiation area of ​​the laser beam is located in the middle of the detection section. When the light-shielding plate moves on the running section, the centrifugal wheel rotates at a relatively slow speed. When the light-shielding plate is about to enter the detection section, the magnetic block at the end of the detection section applies magnetic force to the magnetic component, thereby changing the position of the drive shaft. When the light-shielding plate enters the detection section, the centrifugal wheel rotates at a faster speed, thus ensuring the cooling effect of the light-shielding plate. When the light-shielding plate has completely passed the irradiation area and is about to leave the detection section, the magnetic block at the end of the detection section applies a reverse force to the magnetic component, changing the position of the drive shaft again, causing the centrifugal wheel to slow down again. Through the setting of the magnetic block and magnetic component, the centrifugal wheel speed can automatically switch during normal operation of the light-shielding plate without additional operation, making it convenient to use.

[0017] Preferably, the magnetic block is an electromagnet.

[0018] By adopting the above technical solution, the polarity and magnetic force of the magnetic block can be controlled, allowing for adjustment according to usage requirements and making it convenient to use. When the test is completed and the light-shielding plate is reset, the magnetic block can also be de-energized to demagnetize it, thus enabling the light-shielding plate to move at high speed from the end of the guide rail to the beginning for standby without switching.

[0019] Preferably, the inner wall of the output shaft of the drive motor is provided with a limiting groove along the axial direction, and the outer wall of the transmission shaft is fixed with a limiting block that is slidably connected in the limiting groove. When the limiting block is located at one end of the limiting groove, the large centrifugal gear and the small transmission gear are in contact and meshing. When the limiting block is located at the other end of the limiting groove, the small centrifugal gear and the large transmission gear are in centrifugal contact and meshing, and the transmission shaft is always connected to the pulley.

[0020] By adopting the above technical solution, the limiting block and the limiting groove limit the movement path of the transmission shaft, preventing it from disengaging from the pulley or drive motor.

[0021] In summary, this application includes the following beneficial technical effects: Integrating the light-shielding plate into the LIV measurement system of the fiber optic module does not change the original layout of the LIV measurement system in the fiber optic module, while enabling the testing of NA values. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the NA test in the embodiment; Figure 2 This is a structural schematic diagram of an embodiment; Figure 3 This is a top view of the light-shielding plate in the embodiment; Figure 4 This is a schematic diagram of the internal structure of the light-shielding plate in the embodiment; Figure 5This is a schematic diagram of the connection between the drive motor and the transmission shaft in the embodiment; Figure 6 This is a schematic diagram of the connection between the drive shaft and the centrifugal shaft in the embodiment.

[0023] Explanation of reference numerals in the attached figures: 1. Laser; 2. Laser power meter; 3. Shielding plate; 4. Guide rail; 41. Rack; 5. Cooling pipe; 51. Cooling tube; 52. Heat absorber tube; 53. Return water pipe; 54. Centrifugal wheel; 55. Return water wheel; 56. Centrifugal shaft; 561. Large centrifugal gear; 562. Small centrifugal gear; 57. Return water shaft; 58. Synchronous belt; 6. Cooling fan; 71. Traveling gear; 72. Auxiliary gear; 73. Drive motor; 731. Limiting groove; 74. Pulley; 8. Transmission shaft; 81. Large transmission gear; 82. Small transmission gear; 83. Limiting block. Detailed Implementation

[0024] The present application will be further described in detail below with reference to all the accompanying drawings.

[0025] Example

[0026] This application discloses a fiber laser module beam NA testing apparatus, referring to... Figures 1 to 2 It includes a laser 1 and a laser power meter 2 facing the laser 1. The laser emitted by the laser 1 can shine directly onto the laser power meter 2.

[0027] Reference Figures 1 to 3 A vertically placed guide rail 4 is provided between the laser 1 and the laser power meter 2, with the straight line of the laser 1 and the laser power meter 2 perpendicular to the straight line of the guide rail 4. A light-shielding plate 3 is slidably connected inside the guide rail 4. A rack 41 is fixed to the bottom of the guide rail 4, and a traveling gear 71 and several auxiliary gears 72 are rotatably connected below the light-shielding plate 3 and mesh with the rack 41. The traveling gear 71 is connected to a drive motor 73 through a pulley 74. The drive motor 73 is coaxially connected to the pulley 74 through a transmission shaft 8. The pulley 74 drives the traveling gear 71 to rotate, thereby driving the light-shielding plate 3 to move linearly along the guide rail 4.

[0028] Reference Figures 2 to 4 The light-shielding plate 3 is equipped with a cooling pipe 5 filled with coolant to cool the light-shielding plate 3. A cooling fan 6 is located below the light-shielding plate 3. The cooling pipe 5 includes a cooling pipe 51 facing the cooling fan 6 and a heat-absorbing pipe 52 located inside the light-shielding plate 3. The cooling pipe 51 and the heat-absorbing pipe 52 are connected by a return water pipe 53. The coolant absorbs heat and cools the light-shielding plate 3 in the heat-absorbing pipe 52, and then dissipates the heat through the cooling pipe 51, thus circulating the coolant.

[0029] Reference Figures 2 to 4A centrifugal impeller 54 is rotatably connected to the end of the return water pipe 53 near the cooling pipe 51, which drives the coolant to flow from the return water pipe 53 to the heat absorption pipe 52. A return water impeller 55 is rotatably connected to the end of the heat absorption pipe 52 near the cooling pipe 51, which drives the coolant to flow from the heat absorption pipe 52 to the cooling pipe 51. The centrifugal impeller 54 is coaxially connected to a centrifugal shaft 56, and the return water impeller 55 is coaxially connected to a return water shaft 57. The return water shaft 57 and the centrifugal shaft 56 are connected by a synchronous belt 58. The centrifugal impeller 54 and the return water impeller 55 rotate within the cooling pipe 5, applying thrust to the coolant, thereby enabling the coolant to flow within the cooling pipe 5 and improving the cooling effect.

[0030] Reference Figures 2 to 4 The end of the centrifugal shaft 56 extends out of the light shield 3 and is connected to the transmission shaft 8 through the transmission mechanism. The transmission shaft 8 drives the centrifugal shaft 56 and the return water shaft 57 to rotate through the transmission mechanism, which in turn drives the centrifugal wheel 54 and the return water wheel 55 to rotate, thereby promoting the flow of coolant.

[0031] Reference Figures 2 to 5 The output shaft of the drive motor 73 has a coaxial insertion hole, and the end of the drive shaft 8 is slidably connected to the insertion hole. The drive shaft 8 and the output shaft are slidably connected by a spline, and the drive shaft 8 can slide along its own axis. The other end of the drive shaft 8 is slidably connected to the pulley 74 by a spline. That is, the drive shaft 8 can move linearly between the pulley 74 and the drive motor 73.

[0032] Reference Figures 2 to 5 The inner wall of the insertion hole is provided with a strip-shaped limiting groove 731 along the axis of the output shaft, and a limiting block 83 is fixedly connected to the outer wall of the transmission shaft 8 and slidably connected in the limiting groove 731. The limiting block 83 and the limiting groove 731 limit the stroke of the transmission shaft 8, ensuring that the transmission shaft 8 is always connected to the pulley 74 and the output shaft.

[0033] Reference Figures 3 to 6 The transmission mechanism includes a large centrifugal gear 561, a small centrifugal gear 562, a large transmission gear 81, and a small transmission gear 82. The large transmission gear 81 and the small transmission gear 82 are coaxially fixed on the transmission shaft 8, and the large centrifugal gear 561 and the small centrifugal gear 562 are coaxially fixed on the centrifugal shaft 56. The large transmission gear 81 meshes with the small centrifugal gear 562, and the small transmission gear 82 meshes with the large centrifugal gear 561.

[0034] Reference Figures 3 to 6The distance between the large transmission gear 81 and the small transmission gear 82 is equal to the distance between the large centrifugal gear 561 and the small centrifugal gear 562, and this distance is greater than the thickness of the large centrifugal gear 561, the small centrifugal gear 562, the large transmission gear 81, and the small transmission gear 82. This is to ensure that when the limiting block 83 is located at one end of the limiting groove 731, the large transmission gear 81 is engaged with the small centrifugal gear 562, and the small transmission gear 82 is disengaged from the large centrifugal gear 561; when the limiting block 83 is located at the other end of the limiting groove 731, the small transmission gear 82 is engaged with the large centrifugal gear 561, and the large transmission gear 81 is disengaged from the small centrifugal gear 562.

[0035] Reference Figures 2 to 6 When the shielding plate 3 is far from the beam, it has not yet received light and its temperature is not high. At this time, the small transmission gear 82 and the large centrifugal gear 561 mesh, and the transmission shaft 8 drives the centrifugal shaft 56 to rotate, but the centrifugal shaft 56 rotates slowly. However, when the shielding plate 3 is in the illuminated area, its temperature is higher. At this time, the large transmission gear 81 and the small centrifugal gear 562 mesh, and the transmission shaft 8 drives the centrifugal shaft 56 to rotate at high speed, thereby accelerating the rotation of the centrifugal wheel 54, increasing the flow rate of the coolant, and improving the cooling effect.

[0036] Reference Figures 2 to 6 The guide rail 4 includes a detection section directly opposite the laser power meter 2 and running sections at both ends of the detection section. The illumination area emitted by the laser 1 is located within the detection section, and the width of the illumination area is less than the length of the detection section. Magnetic blocks of opposite polarity, which are electromagnets, are provided at both ends of the detection section. The axis of the magnetic blocks is parallel to the axis of the pulley 74, and a magnetic element is provided at the end of the drive shaft 8 near the pulley 74.

[0037] Reference Figures 2 to 6 When the light-shielding plate 3 travels in the running section, the centrifugal wheel 54 rotates at a relatively slow speed. When the light-shielding plate 3 is about to enter the detection section, the magnetic block at the end of the detection section applies magnetic force to the magnetic component, thereby changing the position of the drive shaft 8. When the light-shielding plate 3 enters the detection section, the centrifugal wheel 54 rotates at a faster speed, thus ensuring the cooling effect of the light-shielding plate 3. When the light-shielding plate 3 has completely passed the illumination area and is about to leave the detection section, the magnetic block at the end of the detection section applies a reverse force to the magnetic component, changing the position of the drive shaft 8 again, causing the centrifugal wheel 54 to slow down again. Through the setting of the magnetic block and magnetic component, the rotation speed of the centrifugal wheel 54 can be automatically switched during normal operation of the light-shielding plate 3 without additional operation, making it convenient to use.

[0038] The implementation principle of the fiber laser module beam NA testing device in this application embodiment is as follows: based on the gradual blocking of the beam, the cross-sectional distribution of the beam is analyzed by detecting the change in light intensity, thereby determining the size of the light spot.

[0039] The operator installs the laser 1 and places a light shield 3 in the direction perpendicular to the light output direction. The distance between the light shield 3 and the fiber optic head is d. The drive motor 73 controls the vertical movement. A laser power meter 2 is placed behind the light shield 3 to read the energy of the incoming beam.

[0040] Gradually block the beam: Move the light-blocking plate 3 into the path of the beam. Initially, the light-blocking plate 3 is completely outside the beam, and the beam is not blocked.

[0041] Gradually entering the beam path: Control the drive motor 73 to move the light shield 3. As the light shield 3 gradually enters the beam, part of the beam will be blocked, causing the light intensity to gradually decrease.

[0042] Measurement of light intensity change: The relationship between the light intensity passing through the laser and the position of the light-shielding plate 3 is measured using laser power meter 2. As the light-shielding plate 3 blocks more of the light beam, the light intensity received by laser power meter 2 gradually decreases.

[0043] Analyze the light intensity variation curve: Record the relationship between the position of the light-shielding plate 3 and the light intensity, and draw the light intensity variation curve.

[0044] Calculate NA: Calculate NA according to requirements. If a 95% energy NA value is required, the positions at 2.5% and 97.5% can be found. The distance between these two positions is 2x. Substitute the corresponding positions into the trigonometric function formula to calculate the NA value. .

[0045] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A fiber laser module beam NA testing device, comprising a laser (1) and a laser power meter (2) facing the laser (1), and a light shield (3) slidably connected between the laser (1) and the laser power meter (2), wherein the sliding direction of the light shield (3) is perpendicular to the emission direction of the laser (1), characterized in that: It also includes a guide rail (4) between the laser (1) and the laser power meter (2), the light shield (3) is slidably connected in the guide rail (4), the light shield (3) is provided with a cooling pipe (5), the cooling pipe (5) is filled with coolant, a cooling fan (6) is provided below the light shield (3), the cooling pipe (5) includes a cooling pipe (51) facing the cooling fan (6) and a heat absorption pipe (52) located inside the light shield (3), the cooling pipe (51) and the heat absorption pipe (52) are connected by a return water pipe (53); The end of the return water pipe (53) near the cooling pipe (51) is rotatably connected to a centrifugal wheel (54) for driving the coolant to flow from the return water pipe (53) to the heat absorption pipe (52). The guide rail (4) is provided with a rack (41). The light shield (3) is rotatably connected to a traveling gear (71) that meshes with the rack (41). The traveling gear (71) is connected to a drive motor (73) through a pulley (74). The output shaft of the drive motor (73) and the pulley (74) are connected by a transmission shaft (8). Both ends of the transmission shaft (8) are slidably connected to the output shaft of the drive motor (73) and the pulley (74) via splines. A large transmission gear (81) and a small transmission gear (82) are coaxially fixed on the transmission shaft (8). The centrifugal wheel (54) is coaxially provided with a centrifugal shaft (56). A large centrifugal gear (561) and a small centrifugal gear (562) are coaxially fixed on the centrifugal shaft (56). 62), the large centrifugal gear (561) and the small transmission gear (82) are meshed, the small centrifugal gear (562) and the large transmission gear (81) are centrifugally meshed, the distance between the large transmission gear (81) and the small transmission gear (82) is equal to the distance between the large centrifugal gear (561) and the small centrifugal gear (562), and is greater than the thickness of the large centrifugal gear (561), the small centrifugal gear (562), the large transmission gear (81) and the small transmission gear (82); The guide rail (4) includes a detection section facing the laser power meter (2) and running sections at both ends of the detection section. The illumination area emitted by the laser (1) is located within the detection section, and the width of the illumination area is less than the length of the detection section. Magnetic blocks with opposite polarities are provided at both ends of the detection section. The axis of the magnetic blocks is parallel to the axis of the pulley (74). Magnetic elements are provided at the end of the transmission shaft (8) near the pulley (74).

2. The fiber laser module beam NA testing device according to claim 1, characterized in that: The end of the heat-absorbing tube (52) near the cooling tube (51) is rotatably connected to a water return wheel (55) for driving the coolant to flow from the heat-absorbing tube (52) to the cooling tube (51).

3. The fiber laser module beam NA testing device according to claim 2, characterized in that: The return water wheel (55) is coaxially connected to the return water shaft (57), and the return water shaft (57) and the centrifugal shaft (56) are connected by a synchronous belt (58).

4. The fiber laser module beam NA testing device according to claim 1, characterized in that: The magnetic block is an electromagnet.

5. The fiber laser module beam NA testing device according to claim 1, characterized in that: The inner wall of the output shaft of the drive motor (73) is provided with a limiting groove (731) along the axial direction. The outer wall of the transmission shaft (8) is fixed with a limiting block (83) that is slidably connected in the limiting groove (731). When the limiting block (83) is located at one end of the limiting groove (731), the large centrifugal gear (561) and the small transmission gear (82) are in contact and meshing. When the limiting block (83) is located at the other end of the limiting groove (731), the small centrifugal gear (562) and the large transmission gear (81) are in centrifugal contact and meshing. The transmission shaft (8) is always connected to the pulley (74).

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