CN219627096U

CN219627096U - High-power optical fiber laser

Info

Publication number: CN219627096U
Application number: CN202320374883.7U
Authority: CN
Inventors: 高旭恒; 张先明; 刘进辉; 丁建武
Original assignee: Nantong Jiwatt Laser Technology Co ltd
Current assignee: Nantong Jiwatt Laser Technology Co ltd
Priority date: 2023-03-02
Filing date: 2023-03-02
Publication date: 2023-09-01
Anticipated expiration: 2033-03-02

Abstract

The utility model discloses a high-power fiber laser, which solves the problems of reduced absorption efficiency and excessive residual pumping light power caused by grating heating and temperature drift under high-power pumping and burning out an optical device by placing a beam combiner in a resonant cavity and butt welding a pumping end of the beam combiner, improves the photoelectric conversion efficiency of the high-power fiber laser and enhances the stability of an optical path structure under the high-power pumping condition.

Description

High-power optical fiber laser

Technical Field

The utility model relates to a high-power fiber laser, in particular to a high-power fiber laser for welding.

Background

The fiber laser has the advantages of high light-light conversion efficiency, good beam quality, compact structure, simple and convenient heat dissipation device and the like. But at the same time, the continuous increase of laser power brings about a plurality of problems. The grating in the optical path is irradiated by the signal light and the pumping light, and the heating problem exists under high-power pumping. The higher the pump power, the higher the grating temperature. Further increases in fiber laser power are limited. In addition, the operating wavelength of the diode may drift with current, so when the laser is operated in a state of not full power, the actual wavelength of the diode is not the optimal operating wavelength, resulting in a decrease in the absorption efficiency of the fiber laser, resulting in energy waste, and at the same time, the residual pump light may damage other optical devices.

The pumping mode of placing the beam combiner outside the resonant cavity has the problem that the grating heats under high-power pumping, and the grating is required to bear high-power signal light and also bear high-power pumping light. To ameliorate the above problems, side-pumped coupled integrated gain fibers have been proposed. The integrated optical fiber can solve the problem that the grating heats under high-power pumping. The integrated gain fiber adopting side coupling pumping can improve the heating problem of the grating, but has higher cost.

The technical scheme provided by the utility model can improve the heating problem of the grating, has low cost and simple operation, and can improve the electro-optical conversion efficiency and the stability of the output power of the laser.

Disclosure of Invention

The utility model aims to provide a novel high-power fiber laser, which solves the problems of reduced absorption efficiency caused by grating heating and temperature drift under high-power pumping and burning out optical devices caused by excessive residual pumping light power by placing a beam combiner in a resonant cavity and butt welding a pumping end of the beam combiner, improves the photoelectric conversion efficiency of the high-power fiber laser and enhances the stability of an optical path structure under the high-power pumping condition.

In order to solve the problems, the utility model provides a high-power fiber laser, which comprises a high-reflection grating, a forward beam combiner, a gain fiber, a reverse beam combiner, a low-reflection grating, a cladding light stripper and a laser output head, wherein a first side of the high-reflection grating is connected with a reflecting structure, and a second side of the high-reflection grating is connected with a first side of the forward beam combiner; the second side of the forward combiner is connected with the first side of the gain fiber; the second side of the gain fiber is connected with the first side of the reverse beam combiner; the second side of the reverse beam combiner is connected with the first side of the low reflection grating; the second side of the low reflection grating is connected with the first side of the laser output head; the second side of the laser output head serves as a laser output end for emitting laser light.

Preferably, the laser output head comprises a quartz end cap.

Preferably, a high power fiber laser is used for laser welding or laser cutting.

Preferably, the forward combiner comprises a plurality of pump arms, part or all of which are connected with the pump light sources; the backward beam combiner comprises a plurality of pumping arms, wherein part or all of the pumping arms are connected with a pumping light source.

Preferably, a plurality of pump light sources are included for connecting the different pump arms.

Preferably, the pump comprises one or more pumping arms with a spare forward beam combiner, and the pump comprises one or more pumping arms with a spare backward beam combiner; and butt welding the spare pump arm of the forward beam combiner and the spare pump arm of the reverse beam combiner.

Preferably, when a plurality of free pumping arms of the forward beam combiner and/or a plurality of free pumping arms of the backward beam combiner are included, the free pumping arms of the forward beam combiner are welded with other free pumping arms of the forward beam combiner and/or the free pumping arms of the backward beam combiner are welded with other free pumping arms of the backward beam combiner.

The utility model has the beneficial effects that the beam combiner is arranged in the resonant cavity; and a beam combiner with multiple pumping arms is adopted, and the spare pumping arms of the beam combiner are butt welded. The problem that the fiber bragg grating heats under high-power pumping can be solved. Meanwhile, the electro-optical conversion efficiency is improved, the residual pump light is reduced, and the working stability of the laser is enhanced;

drawings

Fig. 1 is a schematic structural view of the present utility model.

Detailed Description

The technical scheme of the utility model is further described below by the specific embodiments with reference to the accompanying drawings.

As shown in fig. 1, the present utility model provides a high-power fiber laser, which mainly includes a high reflection grating (HR), a Forward Combiner (Forward Combiner), a gain fiber (YDF), a backward Combiner (Backward Combiner), a low reflection grating (OC), a cladding stripper (CPS), and a laser output head (QBH).

The first side of the high-reflection grating is connected with the reflecting structure, and the second side of the high-reflection grating is connected with the first side of the forward beam combiner; the second side of the forward combiner is connected with the first side of the gain fiber; the second side of the gain fiber is connected with the first side of the reverse beam combiner; the second side of the reverse beam combiner is connected with the first side of the low reflection grating; the second side of the low reflection grating is connected with the first side of the laser output head; the second side of the laser output head serves as a laser output end for emitting laser light.

Preferably, the laser output head comprises a quartz end cap.

Preferably, the reflecting structure may be a reflecting mirror or a reflecting structure such as a reflecting film or a reflecting grating coated on the end surface.

As shown in fig. 1, unlike the prior art solution, the pumping solution places both the forward and reverse combiners inside the resonator. The high-power pump light emitted by the diode is combined by the beam combiner, and then directly enters the resonant cavity without passing through the grating. The problem that the grating heats under high-power pumping is avoided.

The forward beam combiner and the backward beam combiner adopt a beam combiner with a plurality of pumping arms, and preferably, the forward beam combiner comprises a plurality of pumping arms, and part or all of the forward beam combiner is connected with a pumping light source; the backward beam combiner comprises a plurality of pumping arms, wherein part or all of the pumping arms are connected with a pumping light source. Preferably, a plurality of pump light sources are included for connecting the different pump arms.

When part of the forward beam combiner is connected with the pump light source, namely the pump light source comprises one or more spare pump arms of the forward beam combiner, and part of the backward beam combiner is connected with the pump light source, namely the pump light source comprises one or more spare pump arms of the backward beam combiner; the spare pump arms (1, 2, etc.) of the forward beam combiner and the spare pump arms (1 ', 2', etc.) of the backward beam combiner are butt welded. Through the operation, residual pump light which is not absorbed by the optical fiber is output through the redundant pump arm of the beam combiner, and then enters the resonant cavity again through the beam combiner at the other side to be absorbed again by the gain optical fiber, so that the utilization rate of the pump light is improved, the electro-optical conversion efficiency is improved, and meanwhile, the stability of the output power of the laser is improved.

The butt welding manner of the redundant pump arms of the beam combiner can also adopt other manners, preferably, when the redundant pump arms of the forward beam combiner and/or the redundant pump arms of the backward beam combiner are/is included, for example, the redundant pump arms of the forward beam combiner and other redundant pump arms of the forward beam combiner and/or the redundant pump arms of the backward beam combiner and other redundant pump arms of the backward beam combiner can be welded.

The technical principle of the present utility model is described above in connection with the specific embodiments. The description is made for the purpose of illustrating the general principles of the utility model and should not be taken in any way as limiting the scope of the utility model. Other embodiments of the utility model will be apparent to those skilled in the art from consideration of this specification without undue burden.

Claims

1. A high-power fiber laser comprises a high-reflection grating, a forward beam combiner, a gain fiber, a backward beam combiner, a low-reflection grating, a cladding light stripper and a laser output head, wherein a first side of the high-reflection grating is connected with a reflecting structure, and a second side of the high-reflection grating is connected with a first side of the forward beam combiner; the second side of the forward combiner is connected with the first side of the gain fiber; the second side of the gain fiber is connected with the first side of the reverse beam combiner; the second side of the reverse beam combiner is connected with the first side of the low reflection grating; the second side of the low reflection grating is connected with the first side of the laser output head; the second side of the laser output head serves as a laser output end for emitting laser light.

2. The high power fiber laser of claim 1, wherein the laser output head comprises a quartz end cap, and the reflecting structure is a reflecting mirror or an end surface coated with a reflecting film or a reflecting grating.

3. The high power fiber laser of claim 1, wherein the high power fiber laser is used for laser welding or laser dicing.

4. The high power fiber laser of claim 1, the forward combiner comprising a plurality of pump arms, some or all of which are connected to a pump light source; the backward beam combiner comprises a plurality of pumping arms, wherein part or all of the pumping arms are connected with a pumping light source.

5. The high power fiber laser of claim 4, comprising multiple pump light sources for connecting different pump arms.

6. The high power fiber laser of claim 1, comprising one or more pump arms free of forward combiners, comprising one or more pump arms free of reverse combiners; and butt welding the spare pump arm of the forward beam combiner and the spare pump arm of the reverse beam combiner.

7. The high power fiber laser of claim 1, when comprising a plurality of forward combiner free pump arms and/or comprising a plurality of reverse combiner free pump arms, welding the forward combiner free pump arms with other free pump arms of the forward combiner and/or welding the reverse combiner free pump arms with other free pump arms of the reverse combiner.