CN218677961U

CN218677961U - Test device for testing conversion efficiency of rare earth doped gain optical fiber pump

Info

Publication number: CN218677961U
Application number: CN202223229417.4U
Authority: CN
Inventors: 周友源; 郑彬; 魏鹏; 郑熙; 张海亮
Original assignee: Fuzhou Photop Qptics Co ltd
Current assignee: Fuzhou Photop Qptics Co ltd
Priority date: 2022-12-02
Filing date: 2022-12-02
Publication date: 2023-03-21
Anticipated expiration: 2032-12-02

Abstract

The utility model discloses a test device of rare earth doping gain optical fiber pumping conversion efficiency, it includes pumping source, high reflection of light fiber grating, low reflection of light fiber grating, collimater and power meter based on centreless optic fibre, the tail fiber of pumping source with the input butt fusion of high reflection of light fiber grating, the output butt fusion of high reflection of light fiber grating and the rare earth doping optic fibre one end butt fusion of awaiting measuring; the input end of the low-reflection fiber grating is welded with the other end of the rare earth doped fiber to be detected; the output end of the low-reflection fiber grating is welded to the coreless fiber-based collimator, and the output end of the coreless fiber-based collimator is aligned to the receiving end of the power meter. The utility model discloses avoided traditional end cap structure, also avoided using the expensive equipment of butt fusion end cap to thereby the design of centreless optic fibre reduces power density in the collimater is inside to reduce the temperature rise, dependable performance.

Description

Test device for testing conversion efficiency of rare earth doped gain optical fiber pump

Technical Field

The utility model relates to an optics and laser optoelectronics technical field especially relate to a test device of test tombarthite doping gain optical fiber pumping conversion efficiency.

Background

The high-power optical fiber laser is a device for generating visible light or invisible light by utilizing a stimulated radiation method, has a complex structure and a high technical barrier, is a comprehensive system consisting of a large number of optical materials and components, and has wide application prospects in the fields of machining, national defense and military industry, precision manufacturing, aerospace and the like. And the quality level of the rare earth doped gain fiber which is taken as the most core component of the high-power fiber laser directly determines the performance of the fiber laser in all aspects. Therefore, before a large amount of rare earth doped gain fibers are put into the production of fiber lasers, the light transmission performance of the rare earth doped gain fibers needs to be rapidly and accurately detected and judged. The existing test system usually adopts a pump source, a fiber grating and a fiber end cap to test the rare earth doped gain fiber. However, the fusion of the optical fiber end cap with the conventional optical fiber is difficult, requires special equipment to complete, and is expensive.

In addition, for fiber grating manufacturers, there are a certain range of errors and fluctuations in some working parameters of the fiber gratings produced by the manufacturers, and it is necessary to verify the precision and accuracy of their performance parameters by a test system. The simulation of the fiber grating in the working environment to test a series of specific data such as efficiency, working temperature, aging parameters and the like of the fiber grating in the working state of the laser is particularly important.

Disclosure of Invention

The utility model aims at providing a test device of test tombarthite doping gain optical fiber pumping conversion efficiency, the test demand that the cost is lower, do not need expensive professional equipment butt fusion end cap, only need conventional optical fiber splicer just can realize.

The utility model adopts the technical proposal that:

a testing device for testing pumping conversion efficiency of rare earth doped gain optical fibers comprises a pumping source, a high-reflection fiber grating, a low-reflection fiber grating, a collimator based on coreless optical fibers and a power meter, wherein a tail fiber of the pumping source is welded with an input end of the high-reflection fiber grating, an output end of the high-reflection fiber grating is welded with one end of a rare earth doped optical fiber to be tested, and an input end of the low-reflection fiber grating is welded with the other end of the rare earth doped optical fiber to be tested; the output end of the low-reflection fiber grating is in fusion connection with the coreless fiber-based collimator, and the output end of the coreless fiber-based collimator is aligned with the receiving end of the power meter.

Furthermore, the low-reflection fiber grating light source further comprises a cladding light filter which is sleeved at the output end of the low-reflection fiber grating.

Further, preferably, the reflectivity of the high-reflectivity fiber grating is greater than 99.5%, the reflectivity of the low-reflectivity fiber grating is approximately equal to 10%, and the side mode suppression ratio of the high-reflectivity fiber grating to the low-reflectivity fiber grating is greater than 10.

Furthermore, the collimator based on the coreless optical fiber comprises an optical fiber head, a C-Lens and a glass sleeve, wherein the optical fiber head comprises a capillary structure, a section of coreless optical fiber is welded in the capillary structure, and the length of the coreless optical fiber is accurately designed and processed in advance according to the conditions of beam expansion and focusing of an optical path.

Furthermore, the end faces of an optical fiber head and a C-lens in the collimator based on the coreless optical fiber are both plated with optical antireflection films and have higher laser damage threshold values.

The utility model adopts the above technical scheme, utilize the high fine grating of reflection of light and the fine grating of low reflection of light to form the resonant cavity, after pump light coupled in the tombarthite doping optic fibre as the gain medium, the photon on the pump wavelength is absorbed by doping optic fibre medium, and the light wave of stimulated emission forms laser output through the feedback and the oscillation of resonant cavity, and further lets light penetrate the entering power meter after expanding the beam and the collimation of lens through centreless optic fibre. The utility model discloses a testing arrangement uses ordinary optical fiber splicer just can build test system fast, traditional end cap structure has been avoided, also avoid using the expensive equipment of butt fusion end cap, thereby coreless fiber design can reduce power density at the inside this kind of structure of collimater and reduce the temperature rise, the test cost is lower, the dependable performance, stable in structure, this light path test system both can regard as the test system of gain optic fibre simultaneously, also can regard as the test system of height reflection of light fiber grating (FBG) to verify its performance.

Drawings

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments;

fig. 1 is a schematic structural diagram of a testing apparatus for testing the conversion efficiency of a rare-earth doped gain fiber pump according to the present invention;

figure 2 is an enlarged view of the coreless fiber based collimator structure of region a of figure 1.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application.

As shown in fig. 1 or 2, the utility model discloses a test device of rare earth doping gain fiber pumping conversion efficiency, including pumping source 1, high reflection of light fiber grating 2, low reflection of light fiber grating 4, collimater 7 and power meter 6 based on coreless fiber, the tail fiber of pumping source 1 with the input butt fusion of high reflection of light fiber grating 2, the output of high reflection of light fiber grating 2 and the butt fusion of 3 one ends of rare earth doping optic fibre that await measuring, the input of low reflection of light fiber grating 4 have with the butt fusion of 3 other ends of rare earth doping optic fibre that await measuring; the output end of the low reflective fiber grating 4 is welded with the coreless fiber based collimator 7, and the output end of the coreless fiber based collimator 7 is aligned with the receiving end of the power meter 6.

Further, the low-reflection fiber grating light source further comprises a cladding light filter 5, and the cladding light filter 5 is sleeved at the output end of the low-reflection fiber grating 4.

Further, preferably, the reflectivity of the high-reflectivity fiber grating 2 is greater than 99.5%, the reflectivity of the low-reflectivity fiber grating 4 is approximately equal to 10%, and the side mode suppression ratio of the high-reflectivity fiber grating 2 to the low-reflectivity fiber grating 4 is greater than 10.

Further, the collimator 7 based on the coreless optical fiber comprises an optical fiber head 8, a C-Lens 9 and a glass sleeve 10, wherein the optical fiber head 8 and the C-Lens 9 are respectively sleeved in two ends of the glass sleeve 10; the optical fiber head 8 comprises a capillary structure, a section of coreless optical fiber 81 is welded in the capillary structure, and the length of the coreless optical fiber 81 is accurately designed and processed in advance according to the conditions of beam expansion and focusing of an optical path.

Furthermore, the end faces of the optical fiber head 8 and the C-Lens 9 contained in the collimator 7 based on the coreless optical fiber are both plated with optical antireflection films and have higher laser damage threshold.

The utility model discloses a test procedure as follows:

step (1): testing the output power P1 of the pump light after passing through the high-reflection grating; the details are as follows:

firstly, the tail part of the optical fiber of the pumping source 1 is welded with the input end of the high-reflection fiber grating 2; then aligning the output end of the high-reflection grating with a probe of a power meter 6; and measuring the output power of a group of pump light after passing through the high-reflection grating, and marking as P1.

Step (2): testing the output power P2 of the pump light after passing through the optical paths of the high-reflection fiber bragg grating 2, the rare earth-doped optical fiber to be tested, the low-reflection fiber bragg grating 4 and the collimator 7 based on the coreless optical fiber; the specific details are as follows:

taking a certain length of rare earth doped optical fiber to be measured, wherein two ends of the rare earth doped optical fiber to be measured are respectively welded with a high reflective fiber grating 2 and a low reflective fiber grating 4, the output end of the low reflective fiber grating 4 is welded with the input end of a collimator 7 based on a coreless fiber, so that light sequentially passes through a pumping source 1, the high reflective fiber grating 2, the rare earth doped optical fiber to be measured, the low reflective fiber grating 4 and the collimator 7 based on the coreless fiber, and the output end of the collimator 7 based on the coreless fiber is aligned with a probe of a power meter 6 to be received, thereby measuring a group of output power P2;

and (3): testing the output power P3 of the pump light after passing through the light paths of a high-reflection fiber grating 2, a rare earth-doped fiber to be tested, a low-reflection fiber grating 4, a cladding light filter 5 and a collimator 7 based on a coreless fiber; the specific details are as follows:

disconnecting the low-reflection grating and the collimator 7 based on the coreless fiber, connecting a cladding light filter 5 between the low-reflection grating and the collimator 7 based on the coreless fiber, and enabling light to sequentially pass through the pumping source 1, the high-reflection fiber grating 2, the rare earth doped fiber to be detected, the low-reflection fiber grating 4, the collimator 7 based on the coreless fiber and the cladding light filter 5, wherein the output end of the collimator 7 based on the coreless fiber is aligned with a probe of the power meter 6 to be received, so that a group of output power P3 is detected;

step (4) calculation

P2 is the power of the light containing the cladding, and P3 is the power after filtering the cladding

Thus P2-P3 are cladding optical powers.

(P2-P3)/P1 is the ratio of cladding light to P1.

The conversion efficiency of the pump is 100 percent- (P2-P3)/P1

The utility model adopts the above technical scheme, utilize the fine grating 2 of high reflection of light and the fine grating 4 formation resonant cavity of low reflection of light, after pump light income tombarthite doping optical fiber 3 as the gain medium, the photon on the pumping wavelength is absorbed by doping optical fiber medium, and the light wave of stimulated emission forms laser output through the feedback and the oscillation of resonant cavity, and further lets light jet out behind the collimation of the beam expanding of coreless fiber and lens and gets into power meter 6. The utility model discloses a testing arrangement uses ordinary optical fiber splicer just can build test system fast, traditional end cap structure has been avoided, also avoid using the expensive equipment of butt fusion end cap, thereby coreless fiber design can reduce power density at the inside this kind of structure of collimater and reduce the temperature rise, the test cost is lower, the dependable performance, stable in structure, this light path test system both can regard as the test system of gain optic fibre simultaneously, also can regard as the test system of height reflection of light fiber grating 4 (FBG) to verify its performance.

It is to be understood that the embodiments described are only a few embodiments of the present application and not all embodiments. The embodiments and features of the embodiments in the present application may be combined with each other without conflict. The components of the embodiments of the present application, generally described and illustrated in the figures herein, can be arranged and designed in a wide variety of different configurations. Thus, the detailed description of the embodiments of the present application is not intended to limit the scope of the claimed application, but is merely representative of selected embodiments of the application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Claims

1. The utility model provides a test device of test tombarthite doping gain optical fiber pumping conversion efficiency which characterized in that: the fiber laser comprises a pumping source, a high-reflection fiber grating, a low-reflection fiber grating, a collimator based on a coreless fiber and a power meter, wherein a tail fiber of the pumping source is welded with the input end of the high-reflection fiber grating, the output end of the high-reflection fiber grating is welded with one end of a rare earth doped fiber to be detected, and the input end of the low-reflection fiber grating is welded with the other end of the rare earth doped fiber to be detected; the output end of the low-reflection fiber grating is in fusion connection with the coreless fiber-based collimator, and the output end of the coreless fiber-based collimator is aligned with the receiving end of the power meter.

2. The testing device for testing the conversion efficiency of the rare-earth doped gain optical fiber pump according to claim 1, wherein: the low-reflection fiber grating light filter also comprises a cladding light filter which is sleeved at the output end of the low-reflection fiber grating.

3. The testing device for testing the conversion efficiency of the rare-earth doped gain optical fiber pump according to claim 1, wherein: the reflectivity of the high-reflection fiber grating is more than 99.5%, the reflectivity of the low-reflection fiber grating is approximately equal to 10%, and the side mode suppression ratio of the high-reflection fiber grating to the low-reflection fiber grating is more than 10.

4. The testing device for testing the conversion efficiency of the rare-earth doped gain optical fiber pump according to claim 1, wherein: the collimator based on the coreless optical fiber comprises an optical fiber head, a C-Lens and a glass sleeve, wherein the optical fiber head comprises a capillary structure, a section of coreless optical fiber is welded in the capillary structure, and the length of the coreless optical fiber is accurately designed and processed in advance according to the conditions of beam expansion and focusing of an optical path.

5. The apparatus for testing rare-earth doped gain fiber pump conversion efficiency according to claim 1, wherein: the end faces of the optical fiber head and the C-lens contained in the collimator based on the coreless optical fiber are both plated with optical antireflection films and have higher laser damage threshold values.