CN115425507A - Distributed gain high-power all-fiber laser resonant cavity - Google Patents
Distributed gain high-power all-fiber laser resonant cavity Download PDFInfo
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- CN115425507A CN115425507A CN202211205667.6A CN202211205667A CN115425507A CN 115425507 A CN115425507 A CN 115425507A CN 202211205667 A CN202211205667 A CN 202211205667A CN 115425507 A CN115425507 A CN 115425507A
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- 239000000835 fiber Substances 0.000 title claims abstract description 147
- 239000013307 optical fiber Substances 0.000 claims abstract description 49
- 238000003491 array Methods 0.000 claims abstract 2
- 238000002310 reflectometry Methods 0.000 claims description 4
- 150000002500 ions Chemical class 0.000 claims description 3
- 238000000034 method Methods 0.000 abstract description 6
- 230000008569 process Effects 0.000 abstract description 6
- 238000011161 development Methods 0.000 abstract description 4
- 238000005086 pumping Methods 0.000 abstract description 4
- 239000002657 fibrous material Substances 0.000 abstract description 2
- 230000010354 integration Effects 0.000 description 5
- 238000012545 processing Methods 0.000 description 3
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- 238000005516 engineering process Methods 0.000 description 2
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- 238000012681 fiber drawing Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/05—Construction or shape of optical resonators; Accommodation of active medium therein; Shape of active medium
- H01S3/06—Construction or shape of active medium
- H01S3/063—Waveguide lasers, i.e. whereby the dimensions of the waveguide are of the order of the light wavelength
- H01S3/067—Fibre lasers
- H01S3/0675—Resonators including a grating structure, e.g. distributed Bragg reflectors [DBR] or distributed feedback [DFB] fibre lasers
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/09—Processes or apparatus for excitation, e.g. pumping
- H01S3/091—Processes or apparatus for excitation, e.g. pumping using optical pumping
- H01S3/094—Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light
- H01S3/094042—Processes or apparatus for excitation, e.g. pumping using optical pumping by coherent light of a fibre laser
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01S—DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL
- H01S3/00—Lasers, i.e. devices using stimulated emission of electromagnetic radiation in the infrared, visible or ultraviolet wave range
- H01S3/10—Controlling the intensity, frequency, phase, polarisation or direction of the emitted radiation, e.g. switching, gating, modulating or demodulating
- H01S3/13—Stabilisation of laser output parameters, e.g. frequency or amplitude
- H01S3/1305—Feedback control systems
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- Lasers (AREA)
Abstract
The invention relates to a distributed gain high-power all-fiber laser resonant cavity. The adopted technical scheme is as follows: the system comprises a high-power all-fiber laser resonant cavity array and a multi-core fiber beam combiner which are connected; the laser resonant cavity arrays are the same, and the output optical fibers of the shared multi-core optical fiber beam combiner are used as output end resonant cavity mirrors; the input end of the multi-core optical fiber combiner is separated into a plurality of input tail fibers corresponding to fiber cores of output optical fibers of the multi-core optical fiber combiner, and the input tail of the multi-core optical fiber combiner and the laser output optical fibers of the laser resonant cavity array have matched fiber core mode field parameters; and the output optical fiber of the multi-core beam combiner is provided with a laser feedback element. The invention can greatly improve the pumping light power bearing capacity of the high-power all-fiber laser resonant cavity and effectively reduce the heat management difficulty of the high-power all-fiber laser, thereby greatly improving the output power level of the high-power all-fiber laser under the condition of the development process level of the existing high-power laser fiber material and device.
Description
Technical Field
The invention relates to the technical field of laser, in particular to a distributed gain high-power all-fiber laser resonant cavity.
Background
The high-power all-fiber laser has the advantages of good beam quality, high electro-optical efficiency, no debugging and maintenance, flexible laser output, small volume, light weight, long service life and the like, gradually replaces the original chemical, gas and common solid lasers in the application fields of industrial processing, national defense, military and the like, and realizes wide application. In recent years, the rapid development of application technologies such as high-power laser processing, for example, has been in progress: the processing speed of laser industries such as laser cutting, welding and the like is continuously improved, and more urgent needs are brought to high-power all-fiber lasers with higher power levels.
The high-power all-fiber laser uses core fiber devices such as a large mode field gain fiber and a fiber grating, a high-power fiber coupling semiconductor laser, a pumping coupler and the like, generally adopts a high-power all-fiber laser resonant cavity to generate kilowatt-level high-beam-quality fiber laser, and then realizes the amplification output of the fiber laser power through the high-power all-fiber laser resonant cavity. In order to raise the output power level, the pumping power needs to be increased, which makes the core fiber device of the high-power all-fiber laser intensively bear the higher-power pumping light, laser and heat generated by laser gain. Therefore, the state of the art integration advances directly from the core fiber device performance of high power all fiber lasers. However, the development process level of the core fiber device is difficult to meet the requirement of greatly increasing the output power level, which results in the bottleneck of the integration technology. In recent years, the output power level of the high-power all-fiber laser has not obviously increased.
Disclosure of Invention
The invention aims to provide a distributed gain high-power all-fiber laser resonant cavity to solve the bottleneck problem of the improvement of the output power level of the conventional high-power all-fiber laser.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
a distributed gain high-power all-fiber laser resonant cavity comprises a high-power all-fiber laser resonant cavity array and a multi-core fiber beam combiner which are connected;
the high-power all-fiber laser resonant cavity array has completely same devices, integration technical parameters and processes, and shares the output fiber of the multi-core fiber beam combiner as an output end resonant cavity mirror;
the input end of the multi-core optical fiber combiner is separated into a plurality of input tail fibers corresponding to fiber cores of output optical fibers of the multi-core optical fiber combiner, and the input tail fibers of the multi-core optical fiber combiner and the laser output optical fibers of the high-power all-fiber laser resonant cavity array have matched fiber core mode field parameters;
and the output optical fiber of the multi-core beam combiner is provided with a laser feedback element.
Furthermore, the laser feedback element is formed by installing a laser collimating mirror and a partial reflecting plane mirror at the output end of the output optical fiber of the multi-core beam combiner.
Furthermore, the laser feedback element is a fiber grating engraved on the fiber core of the output fiber of the multi-core beam combiner.
Furthermore, the output optical fiber of the multi-core optical fiber combiner is a multi-core optical fiber without doping gain ions, the diameter of the core of the multi-core optical fiber combiner is represented by Dcore, the Dcore is less than or equal to 30 mu m, the distance between the cores is represented by Dcore, and the gap (Dcore-Dcore) between the adjacent cores is less than or equal to 20 mu m.
Compared with the prior art, the invention has the advantages that:
1) The invention uses the multi-core fiber combiner to realize the array distributed gain of the high-power all-fiber laser resonant cavity, effectively reduces the laser damage risk of core fiber devices such as a large mode field fiber grating, a large mode field gain fiber, a high-power fiber pump coupler and the like, and can obtain the high-power fiber laser with high beam quality by using the high-power all-fiber laser resonant cavity.
2) The invention uses the array distributed high-power all-fiber laser resonant cavity, realizes the dispersion distribution of high-power pump light, and greatly improves the pump light power bearing capacity of the high-power all-fiber laser resonant cavity.
3) When the high-power all-fiber laser resonant cavity works, heat generated by laser gain is distributed in the high-power all-fiber laser resonant cavity array in a dispersing way, and the heat management difficulty of the high-power all-fiber laser is effectively reduced.
4) By optimizing the integration parameters and the process of the multi-core beam combiner and the high-power all-fiber laser resonant cavity array, tens of thousands of watts of fiber laser output close to the diffraction limit can be obtained based on the invention under the development process level condition of the existing high-power laser fiber material and device.
5) Compared with the MOPA structure that the prior high-power all-fiber laser generally adopts a high-power all-fiber laser resonant cavity and a high-power all-fiber laser amplifier, the high-power all-fiber laser based on the invention only comprises a primary high-power all-fiber laser resonant cavity, the control difficulty is reduced when the high-power all-fiber laser based on the invention is integrated with laser application systems such as laser industrial processing and the like, and the system compatibility is higher.
6) Two structures selected by the laser feedback element can be used for the output end resonant cavity mirror of the invention, and the output laser power bearing capacity higher than that of the output cavity mirror of the existing high-power all-fiber laser resonant cavity is obtained. The laser feedback element consisting of the laser collimating mirror and the partial reflecting plane mirror is separated from the output optical fiber of the multi-core beam combiner, so that the manufacture, installation, maintenance, replacement and upgrade are simple and easy to operate; the laser feedback element formed by directly writing fiber gratings on the output fibers of the multi-core beam combiner, the high-power all-fiber laser resonant cavity array and the multi-core fiber beam combiner form an integrated high-power all-fiber laser resonant cavity together, and high-power fiber lasers with flexible output are obtained and are easy to integrate with devices such as laser processing and the like.
Drawings
Fig. 1 is a schematic diagram of the structure of the present invention.
Reference numerals: the optical fiber laser system comprises a 1-high-power all-fiber laser resonant cavity array, a 2-multi-core fiber combiner, a 3-laser output fiber of the high-power all-fiber laser resonant cavity array, an input tail fiber of a 4-multi-core fiber combiner and an output fiber of a 5-multi-core beam combiner.
Detailed Description
The technical solution in the present embodiment will be clearly and completely described below with reference to the embodiments and the accompanying drawings.
Example (b): referring to fig. 1, the distributed gain high-power all-fiber laser resonator provided by the present invention includes a high-power all-fiber laser resonator array 1 and a multi-core fiber combiner 2. The output optical fiber of the multi-core optical fiber beam combiner 2 is a multi-core optical fiber without doping gain ions, the diameter Dcore of the fiber core is less than or equal to 30 mu m, the space between the fiber cores is Dcore, and the space (Dcore-Dcore) between the adjacent fiber cores is less than or equal to 20 mu m. The multi-core beam combiner output optical fiber 5 is provided with a laser feedback element with the laser wavelength reflectivity of R, the laser feedback element can be a laser collimating mirror and a partial reflecting plane mirror arranged at the end of the output optical fiber 5 or an optical fiber grating directly engraved on the fiber core of the multi-core beam combiner output optical fiber 5, the reflectivity R of the laser feedback element in the two structures is less than or equal to 90%, and the two structures can enable the output optical fiber to have the laser output and feedback functions at the same time. The input end of the multi-core optical fiber combiner 2 is separated into a plurality of input tail fibers 4 corresponding to fiber cores of output fibers 5 of the multi-core optical beam combiner, and the input tail fibers 4 and the laser output fibers 3 of the high-power all-fiber laser resonant cavity array have the same fiber core mode field parameters. The all-fiber laser resonant cavity array 1 is completely the same, and has completely the same fiber devices, integration technical parameters and processes, the laser feedback elements of the high-reflection-end resonant cavity mirror and the multi-core fiber combiner output fiber 5 have the same laser reflection spectrum center, the output fiber 5 of the multi-core fiber combiner is shared as an output-end resonant cavity mirror, and the output power of the array units FL1-N can be independently adjusted by adjusting the pump light power.
The working principle of the invention is as follows: referring to fig. 1, a plurality of paths of fiber lasers generated by a high-power all-fiber laser resonator array 1 are coupled into an output fiber 5 through an input pigtail 4 of a multi-core fiber combiner corresponding to an output fiber 3 of the multi-core fiber laser resonator array, and are recombined due to strong coupling of a plurality of fiber core light fields of the output fiber 5 to form a bundle of stably-transmitted fiber lasers. The laser feedback element arranged on the output optical fiber 5 outputs one part of the transmitted optical fiber laser, and the other part of the transmitted optical fiber laser is reflected and reversely transmitted, split by the multi-core optical fiber beam combiner 2 and injected into the corresponding high-power all-optical fiber laser resonant cavity array 1 to form optical fiber laser resonance.
When in preparation, one end of the output optical fiber is bundled, fused, tapered and cut, and then correspondingly welded with a plurality of fiber cores of the multi-core optical fiber to form a multi-core optical fiber beam combiner; or when the multicore fiber is drawn, one end of the multicore fiber prefabricated rod is separated according to the fiber core distribution, and the multicore fiber beam combiner with one end separated by the tail fiber can be integrally drawn after the fiber drawing is carried out.
In this embodiment, the all-fiber laser resonator array 1 has better coherence; the multicore fiber has an in-phase supermode close to the diffraction limit. Therefore, the high-power all-fiber laser resonator array 1 can obtain a beam of all-fiber laser beam with high power and high beam quality through the output fiber 5 of the multi-core fiber. For example, the multi-core fiber 5 has 37 cores, and all-fiber laser resonator array units FL1-N can generate fiber lasers with a power of 1000 watts, so that the high-power all-fiber laser resonator array 1 can obtain high-beam-quality fiber lasers with a power of about 3.7 ten thousand watts via the multi-core fiber beam combiner 2.
The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and substitutions can be made without departing from the technical principle of the present invention, and these modifications and substitutions should also be regarded as the protection scope of the present invention.
Claims (4)
1. A distributed gain high-power all-fiber laser resonant cavity is characterized in that: comprises a high-power all-fiber laser resonant cavity array (1) and a multi-core fiber beam combiner (2) which are connected;
the high-power all-fiber laser resonant cavity arrays (1) are completely the same, and the output fiber (5) of the shared multi-core fiber beam combiner is used as an output end resonant cavity mirror;
the input end of the multi-core optical fiber combiner (2) is separated into a plurality of input tail fibers (4) corresponding to the fiber cores of the output optical fibers, and the input tail fibers (4) of the multi-core optical fiber combiner and the laser output optical fibers (3) of the high-power all-fiber laser resonant cavity array have matched fiber core mode field parameters;
and a laser feedback element is arranged on an output optical fiber (5) of the multi-core beam combiner.
2. The distributed gain high power all-fiber laser resonator of claim 1, wherein: the laser feedback element is a laser collimating mirror and a partial reflecting plane mirror which are arranged at the output end of an output optical fiber (5) of the multi-core beam combiner, and the reflectivity R is less than or equal to 90 percent.
3. The distributed gain high power all-fiber laser resonator of claim 1, wherein: the laser feedback element is a fiber grating inscribed on the fiber core of the output fiber (5) of the multi-core beam combiner, and the reflectivity R is less than or equal to 90 percent.
4. The distributed gain high power all-fiber laser resonator of claim 2 or 3, wherein: the output optical fiber (4) of the multi-core optical fiber combiner is a multi-core optical fiber without doping gain ions, the diameter of a fiber core of the multi-core optical fiber combiner is represented as Dcore, the Dcore is less than or equal to 30 mu m, the space between the fiber cores is represented as Dcore, and the gap (Dcore-Dcore) between the adjacent fiber cores is less than or equal to 20 mu m.
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| CN202211205667.6A CN115425507A (en) | 2022-09-30 | 2022-09-30 | Distributed gain high-power all-fiber laser resonant cavity |
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| CN202211205667.6A CN115425507A (en) | 2022-09-30 | 2022-09-30 | Distributed gain high-power all-fiber laser resonant cavity |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114883898A (en) * | 2022-05-24 | 2022-08-09 | 西安工业大学 | Array distributed high-power all-fiber laser amplifier |
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| US20110158266A1 (en) * | 2009-07-06 | 2011-06-30 | Baishi Wang | Passive coherent array using distributed fiber lasers |
| CN103022864A (en) * | 2012-12-13 | 2013-04-03 | 华南理工大学 | Tunable narrow-linewidth array single-frequency fiber laser |
| CN103439773A (en) * | 2013-08-28 | 2013-12-11 | 中国科学院半导体研究所 | High-power all-solid-state continuous laser beam combining system |
| CN103701022A (en) * | 2013-12-19 | 2014-04-02 | 北京工业大学 | Double-resonant-cavity all-optical-fiber mode-locked pulse laser |
| CN206283096U (en) * | 2016-11-25 | 2017-06-27 | 广州市普东医疗设备股份有限公司 | The simple hectowatt grade Bladder stone system of light path |
| CN114498265A (en) * | 2022-01-19 | 2022-05-13 | 北京凯普林光电科技股份有限公司 | Optical fiber laser |
| CN114883898A (en) * | 2022-05-24 | 2022-08-09 | 西安工业大学 | Array distributed high-power all-fiber laser amplifier |
-
2022
- 2022-09-30 CN CN202211205667.6A patent/CN115425507A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20110158266A1 (en) * | 2009-07-06 | 2011-06-30 | Baishi Wang | Passive coherent array using distributed fiber lasers |
| CN103022864A (en) * | 2012-12-13 | 2013-04-03 | 华南理工大学 | Tunable narrow-linewidth array single-frequency fiber laser |
| CN103439773A (en) * | 2013-08-28 | 2013-12-11 | 中国科学院半导体研究所 | High-power all-solid-state continuous laser beam combining system |
| CN103701022A (en) * | 2013-12-19 | 2014-04-02 | 北京工业大学 | Double-resonant-cavity all-optical-fiber mode-locked pulse laser |
| CN206283096U (en) * | 2016-11-25 | 2017-06-27 | 广州市普东医疗设备股份有限公司 | The simple hectowatt grade Bladder stone system of light path |
| CN114498265A (en) * | 2022-01-19 | 2022-05-13 | 北京凯普林光电科技股份有限公司 | Optical fiber laser |
| CN114883898A (en) * | 2022-05-24 | 2022-08-09 | 西安工业大学 | Array distributed high-power all-fiber laser amplifier |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114883898A (en) * | 2022-05-24 | 2022-08-09 | 西安工业大学 | Array distributed high-power all-fiber laser amplifier |
| CN114883898B (en) * | 2022-05-24 | 2024-06-11 | 西安工业大学 | Array distributed high-power all-fiber laser amplifier |
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