CN114976830A - Multi-core doped rare earth ion based multi-wavelength power adjustable optical fiber laser - Google Patents

Abstract

The invention discloses a multi-wavelength power adjustable fiber laser based on multi-core doped rare earth ions. It can realize high-power composite wavelength fiber laser output whose output power is individually controllable by multiple wavelengths. The composite wavelength fiber laser uses a multi-core doped active fiber as the gain fiber, and combines the signal light and the pump light combiner to realize the amplification output of the signal light.

Description

A multi-wavelength power-tunable fiber laser based on multi-core doped rare earth ions

technical field

The invention relates to a multi-wavelength power-adjustable fiber laser based on multi-core doped rare earth ions, which can be used to realize high-power amplifying output of the multi-wavelength fiber laser.

Background technique

As fiber lasers have been widely used in many research fields in society, such as industry, medical, scientific research and so on. Especially with the continuous progress of related technologies in the above research fields, new technical application requirements for laser technology are constantly put forward to meet the application requirements of the continuous improvement of its technology, and promote the rapid development of this related research field, and finally make the society obtain Rapid progress. In recent years, with the gradual maturity of fiber laser technology and its manufacturing process, continuous, quasi-continuous, pulsed, multi-wavelength or single-wavelength, polarization-maintaining or non-polarization-maintaining fiber lasers have formed mature technical products. be used in various industries. With the development of various industries, the development of each industry has gradually moved towards the development direction of fine and precise high-end technology manufacturing, which is used to improve the technical ability to create high-end technology products. In recent years, the fields of medical treatment, material precision processing, and scientific research have also developed rapidly. Among them, the composite wavelength laser technology based on the superposition of multiple wavelength lasers has been applied to the above fields. Such as: multi-wavelength test light source, oral medical treatment, surface treatment of metal materials, etc.

At present, the main technologies used in multi-wavelength lasers are laser frequency doubling, resonator multi-wave oscillation, combination of ASE and grating array, and quantum dot semiconductor laser. The above technologies all have their own unique advantages and some defects in obtaining multiple wavelengths of laser light. Such as 1. Optical frequency doubling: The laser frequency doubling technology greatly expands the wavelength band of the laser, and is the main technical method to convert the laser to the short wavelength direction. This method mainly adopts the combination of pump laser and nonlinear crystal to obtain the output of multi-wavelength laser. This method has certain limitations: (1) the nonlinear crystal has low conversion efficiency, and there are certain limitations in obtaining high power output; (2) due to its spatial structure, compared with all-fiber lasers, its stability and reliability are relatively poor. ③ In order to obtain more wavelengths of laser output, multiple frequency doublings are often required, so it is easy to make the spatial structure more complicated. ④ In terms of application, it is difficult to realize individual regulation of its multiple wavelengths, so its application flexibility is poor. 2. Resonant cavity type This method mainly adopts multi-wavelength grating pair or multi-wavelength coated cavity mirror and gain medium to form multi-wavelength resonant cavity to realize the output of multi-wavelength laser operation. The output power of each wavelength of the multi-wavelength laser obtained in this way is not controllable, which is mainly determined by the loss of the resonator and the gain curve of the gain medium. Moreover, the output power corresponding to each wavelength cannot be individually controlled, so it lacks certain flexibility in application. 3. Amplified spontaneous emission (ASE) is combined with a multi-wavelength grating array. This method uses the spontaneous emission effect of the gain medium to generate a wide spectrum, and then the multi-wavelength grating array separates multiple discrete wavelengths. The multiple discrete wavelength lasers Then, multi-wavelength processing is performed to form a multi-wavelength composite laser. However, the spontaneous emission process is generally accompanied by heavy absorption effect, resulting in poor output efficiency and easy heating of the gain medium. Therefore, this method has serious drawbacks in achieving high power output. In addition, the single wavelength laser output power is not individually controllable. 4. Quantum cascade laser. This method mainly uses quantum semiconductor materials to obtain multi-wavelength lasers. This method can obtain a wide range of laser wavelengths, and its wavelength bands can cover mid-infrared and far-infrared. Due to the limitation of its own physical characteristics, the maximum output power of a single module is generally limited to the watt level, and its price is relatively high. Therefore, it is generally used in the field of scientific research. Furthermore, individual control of the laser output power at a single wavelength cannot be achieved.

The optical fiber output using multi-core technology in the prior art, such as CN101719621A, uses discrete doped cores to realize multi-wavelength output, which is not only complicated to manufacture optical fibers, but also has low space utilization, making it difficult to achieve high-power processing; CN109286122A uses a fan-shaped The regions are divided into multiple doping regions, and the regions are not only easy to influence each other, but also the output laser is difficult to apply in high-power laser processing scenarios; although CN101814687A and others mentioned multi-layer ring-doped amplifying fibers, however, its It is just a simple idea of gain fiber, and it does not solve the problem of how to design the pump and signal input and coupling structure reasonably to reduce coupling loss and laser dissipation, and how to design the structure of all-fiber ingeniously without increasing the laser and energy. Loss rate, which is particularly important in high-power processing scenarios. Every 1% reduction in energy loss of a laser processing device will save tens of thousands of electricity bills. In the field of high-power laser processing, energy needs to be utilized. Rate does a lot of creative work to make it as energy efficient as possible.

In order to solve the two key technical problems that all the above multi-wavelength laser generation technologies coexist and limit their application: 1. The realization of high power output is difficult; 2. The single-wavelength laser output is uncontrollable; 3. There is no simple and stable laser structure The overall coupling and pumping structure can simultaneously improve energy utilization and reduce nonlinear effects. In order to solve the above technical problems, the solution involved in this patent uses a multi-core rare-earth ion-doped fiber as a gain fiber to realize a controllable high-power multi-wavelength fiber laser output.

SUMMARY OF THE INVENTION

The purpose of the present invention is to propose a multi-doped rare earth ion multi-wavelength fiber laser.

In order to solve the above problems, the present invention creatively transforms the structure of the multi-layer fiber core, and skillfully combines the designed fiber bundle structure with the unique multi-core doped fiber to provide a composite wavelength ring spot laser. output of the laser.

The invention discloses a multi-doped rare earth ion multi-wavelength fiber laser, which can realize high-power composite wavelength fiber laser output whose output power is individually controllable by multiple wavelengths.

The composite wavelength fiber laser uses a multi-core doped active fiber as a gain fiber, and combines the signal light and the pump light combiner to realize the amplification and output of the signal light.

The composite wavelength fiber laser mainly includes four parts: signal light and pump light module, signal light and pump light output fiber bundle area, bundle taper area, and multi-core doped active fiber.

The signal light and pump light module includes a signal light module and a pump light module. The signal optical module can output the signal laser to be amplified. Preferably, the signal optical module can simultaneously output the signal laser to be amplified including two wavelengths, which are the first signal laser L1 and the second signal laser L2, respectively. The laser or L1 and the second signal laser L2 can be respectively output from the signal optical module through the respective waveguide output structures or spatial light output structures; preferably, the signal optical module can simultaneously output three wavelengths of the signal laser to be amplified, which are respectively: The first signal laser L1, the second signal laser L2, the third signal laser L3, the first signal laser or L1, the second signal laser L2, and the third signal laser L3 can be output from the respective waveguide output structures or spatial light output structures respectively. Signal light module output; preferably, the signal light module can simultaneously output n kinds of wavelengths (n>3, a positive integer) to be amplified signal laser light, respectively the first signal laser L1, the second signal laser L2, the third signal laser Signal laser light L3, (fourth signal laser light L4) . . . n-th signal laser light Ln. The first signal laser L1, the second signal laser L2, the third signal laser L3, (the fourth signal laser L4)...the n-th signal laser Ln can be respectively output from the signal optical module through the respective waveguide output structures or spatial light output structures .

The pump optical module outputs the corresponding pump light required to realize the signal light amplification. Preferably, the pump light includes pump lasers of multiple wavelengths corresponding to the signal light of multiple wavelengths. Preferably, when the signal optical module can When outputting two wavelengths of signal lasers to be amplified at the same time, which are the first signal laser L1 and the second signal laser L2, respectively, the pump optical module outputs the corresponding pump lights of the two wavelengths, which are the first pumping laser light respectively. P1 and the second pump laser P2; preferably, the signal optical module can simultaneously output three wavelengths of the signal laser to be amplified, which are the first signal laser L1, the second signal laser L2, and the third signal laser L3, respectively, The pump optical module outputs corresponding pump lights of three wavelengths, namely the first pump laser P1, the second pump laser P2, and the third pump laser P3; preferably, the signal optical module can output n wavelengths at the same time (n>3, is a positive integer), the signal lasers to be amplified are respectively the first signal laser L1, the second signal laser L2, the third signal laser L3, (the fourth signal laser L4)...the nth signal laser At Ln, the pump optical module outputs corresponding pump lights of n wavelengths, which are the first pump laser P1, the second pump laser P2, the third pump laser P3...the nth pump laser Pn.

The signal laser corresponds to the laser that can be emitted and/or amplified by the multi-core fiber doped rare-earth ion material, and the pumping laser is the pumping laser that the rare-earth ions can absorb and invert the number of ions. Preferably, the first signal laser L1 corresponds to the first pump laser P1, and the first rare-earth ion material absorbs the first pump laser P1 and inverts the number of ions, and outputs the amplified first signal laser L1; preferably, the second signal laser L2 corresponds to the second pump laser P2, the second rare-earth ion material absorbs the second pump laser P2 and makes the number of ions reversed, and emits the amplified second signal laser L2; preferably, the third signal laser L3 corresponds to the third pump laser P3, the third rare earth ion material absorbs the third pump laser P3 and makes the number of ions reversed, and emits the amplified third signal laser L3; preferably, the nth signal laser Ln corresponds to the nth pump laser Pn, and the nth rare earth ion material Absorb the nth pump laser Pn and make the number of ions reversed, and output the amplified nth signal laser Ln (n>3, which is a positive integer).

Preferably, their respective powers of the first pump laser, the second pump laser, the third pump laser...the nth pump laser are independently adjustable, that is, the power of the first pump laser is independently adjustable, that is, the second pump laser is independently adjustable. The power of the pump laser is independently adjustable, that is, the power of the third pump laser is independently adjustable, that is, the power of the nth pump laser is independently adjustable (n>3, a positive integer), so as to achieve independent output light of each wavelength. Controllable.

Preferably, the powers of the first signal laser, the second signal laser, the third signal laser...the nth signal laser are independently adjustable.

Preferably, the signal laser can be a single-mode signal laser to improve the beam quality of the output light.

Preferably, the pump laser can be a multi-mode pump laser.

The signal light and pump light output fiber bundle area includes the signal fiber and the pump fiber, which bundle the signal fiber and the pump fiber. Preferably, a tube is also included for enclosing the signal fiber and the pump fiber. The tube for surrounding the signal fiber and the pump fiber is a quartz glass tube.

For convenience, the bundle area of the output fibers of the signal light and the pump light is referred to as bundle area below.

Preferably, the refractive index of the silica glass tube is also lower than the core refractive index of the signal fiber (here, lower than the core refractive index of the signal fiber means lower than the core refractive index of all signal fibers).

Preferably, the quartz low refractive index glass tube can be manufactured by doping, and preferably, the quartz low refractive index glass tube is a fluorine-doped or boron quartz low refractive index glass tube.

Preferably, the signal fiber can be a single-mode fiber to obtain good single-mode signal light, and preferably, the signal fiber is a 10/125 single-mode fiber.

Preferably, the pump fiber adopts a multi-mode pump fiber that can accommodate high-power multi-mode light, and preferably, the pump fiber has a parameter of 105/125/0.22.

Preferably, the bundling area is divided into a plurality of area parts, preferably, it may include a first part of the bundling area and a second part of the bundling area; preferably, it may include a first part of the bundling area, a second part of the bundling area, and a third part of the bundling area; Preferably, it may include the first part of the bundling area, the second part of the bundling area, the third part of the bundling area, ... the nth part of the bundling area.

Preferably, each part includes a signal fiber and a pump fiber.

Preferably, the signal fiber is a passive matching fiber capable of transmitting the corresponding laser light excited by the doping corresponding ions.

Preferably, the pump fiber is a pump source coupling output fiber in the pump optical module.

Preferably, the various parts of the cluster area are arranged layer by layer starting from the center and outward.

Preferably, the bundling area has the first part of the bundling area, the second part of the bundling area, the third part of the bundling area, ... the nth area of the bundling area (n>3, a positive integer) from the inside to the outside.

Preferably, the first part of the bundling area is a circular area in the center, the second part of the bundling area is an annular area surrounding the first part of the bundling area, and the third part of the bundling area is an annular area surrounding the second part of the bundling area, ...the nth part of the cluster area (n>3, which is a positive integer) is an annular area surrounding the (n-1)th part of the cluster area.

Each portion of the bundle preferably includes a respective signal fiber and its corresponding pump fiber.

Preferably, the first part of the bundle area includes a first signal fiber and a corresponding first pump fiber, the first signal fiber is used for transmitting the first signal laser L1, the first pump fiber is used for transmitting the first pump laser P1, Preferably, there are one or more first signal fibers, preferably two or more first signal fibers, preferably one or more first pump fibers, preferably two first pump fibers and above; preferably, the second part of the bundle area includes a second signal fiber and a corresponding second pump fiber, the second signal fiber is used to transmit the second signal laser L2, and the second pump fiber is used to transmit the second pump The pump laser P2, preferably one or more second signal fibers, preferably two or more second signal fibers, preferably one or more second pump fibers, preferably, the second pump fibers There are two or more optical fibers; preferably, the third part of the bundle area includes a third signal fiber and a third pump fiber corresponding to it, the third signal fiber is used for transmitting the third signal laser L3, and the third pump fiber is used for Transmission of the third pump laser P3, preferably one or more third signal fibers, preferably two or more third signal fibers, preferably one or more third pump fibers, preferably, There are two or more third pump fibers; preferably, the nth part of the bundle area includes the nth signal fiber and the corresponding nth pump fiber, the nth signal fiber is used to transmit the nth signal laser Ln, and the nth pump fiber The pump fiber is used to transmit the nth pump laser Pn, preferably the number of the nth signal fiber is one or more, preferably, the number of the nth signal fiber is two or more, preferably, the number of the nth pump fiber is one or more , preferably, the number of nth pump fibers is two or more.

Preferably, the first rare earth ion material corresponding to the first signal laser L1 and the first pump laser P1 can be selected from ytterbium-doped material, erbium-doped material, thulium-doped material, neodymium-doped material, holmium-doped material, samarium-doped material, praseodymium-doped material One of rare earth-doped materials such as erbium-ytterbium co-doped materials.

Preferably, the second rare earth ion material corresponding to the second signal laser L2 and the second pump laser P2 can be selected from ytterbium-doped material, erbium-doped material, thulium-doped material, neodymium-doped material, holmium-doped material, samarium-doped material, praseodymium-doped material One of rare earth-doped materials such as erbium-ytterbium co-doped materials. Preferably, the second rare earth ion material should be different from the first rare earth ion material, and can be used to emit different wavelengths that can be controlled by the annular layer, that is, the wavelength of the second signal laser L2 is different from the wavelength of the first signal laser L1.

Preferably, the third rare earth ion material corresponding to the third signal laser L3 and the third pump laser P3 can be selected from ytterbium-doped material, erbium-doped material, thulium-doped material, neodymium-doped material, holmium-doped material, samarium-doped material, praseodymium-doped material One of rare earth-doped materials such as erbium-ytterbium co-doped materials. Preferably, the third rare-earth ion material should be different from the first rare-earth ion material, and the third rare-earth ion material is different from the second rare-earth ion material, so as to emit different wavelengths that can be controlled by the annular layer, that is, the third signal laser L3 The wavelength of the laser light is different from the wavelength of the second signal laser light L2, that is, the wavelength of the third signal laser light L3 is different from the wavelength of the first signal laser light L1.

Preferably, the nth rare earth ion material corresponding to the nth signal laser Ln and the nth pump laser Pn can be selected from ytterbium-doped material, erbium-doped material, thulium-doped material, neodymium-doped material, holmium-doped material, samarium-doped material, praseodymium-doped material One of the materials, erbium-ytterbium co-doped materials, etc. Preferably, the nth rare earth ion material should be different from the rare earth ion material corresponding to other parts of the signal laser and pump laser in the beam area, so as to emit different wavelengths that can be controlled by the annular layer.

The wavelength of the pump light in the relatively inner bundling portion is smaller than the wavelength of the pump light in the relatively outer bundling portion surrounding it, and/or the wavelength of the signal light in the relatively inner bundling portion less than the wavelength of the signal light surrounding its relatively outer portion of the bundle.

Preferably, the signal fiber in the first part of the bundle area is a passive matching fiber capable of transmitting corresponding laser light excited by doped ytterbium ions.

Preferably, the pumping fiber of the first part of the bundle region is a coupling-out fiber of a pumping source outputting laser light capable of pumping the ytterbium ion-doped material. Preferably, the pump source is an optical laser diode (LD) pump source.

Preferably, the signal fiber in the second part of the bundle area is a passive matching fiber capable of transmitting corresponding laser light excited by doped erbium ions.

Preferably, the pumping fiber of the second part of the bundle area is a coupling-out fiber of a pumping source outputting laser light capable of pumping the erbium-ytterbium co-doped ion material. Preferably, the pump source is an optical laser diode (LD) pump source.

Preferably, the signal fiber in the third part of the bundle area is a passive matching fiber capable of transmitting corresponding laser light excited by doped thulium ions.

Preferably, the pumping fiber in the third part of the bundle region is a coupling-out fiber of a pumping source outputting laser light capable of pumping the thulium ion-doped material. Preferably, the pump source is an optical laser diode (LD) pump source.

Preferably, when there is the nth part of the bundle area (n>3, which is a positive integer), appropriate signal fibers, pump fibers and pump sources can be selected.

Preferably, the refractive index of the silica low-refractive index glass tube is lower than the cladding refractive index of the pumping fiber (here lower than the cladding refractive index of the pumping fiber means lower than the cladding refractive index of all pumping fibers).

Preferably, the refractive index of the silica low-refractive index glass tube is lower than the cladding refractive index of the signal fiber (here lower than the cladding refractive index of the signal fiber means lower than the cladding refractive index of all signal fibers).

Preferably, quartz low-refractive index glass tubes are arranged between the various parts of the clustering region. For example, a quartz low-refractive-index glass tube is arranged between the first part of the bundling area and the second part of the bundling area; a quartz low-refractive index glass tube is arranged between the second part of the bundling area and the third part of the bundling area; A quartz low-refractive index glass tube is arranged between the n-1) part and the nth part of the concentrating area. The outermost part of the output fiber bundle area of the signal light and the pump light includes a quartz low-refractive index glass tube. Preferably, the quartz low-refractive index glass tube is a fluorine- or boron-doped low-refractive index glass tube.

The bundling area includes the first part of the bundling area, the second part of the bundling area, and the third part of the bundling area; the first part of the bundling area is basically a circular area, and the outer diameter of the first part of the bundling area is basically 375 μm; the second part of the bundling area is basically an annular area , the inner diameter of the second part of the clustering area is 425 μm, and the outer diameter of the second part of the clustering area is 675 μm; the third part of the clustering area is basically an annular area, the inner diameter of the third part of the clustering area is 725 μm, and the outer diameter of the third part of the clustering area is 725 μm. The diameter is 975 μm (both the inner diameter and the outer diameter mentioned here refer to the diameter).

Preferably, the first rare earth ion material may be a material doped with ytterbium ions, the first signal laser L1 corresponding to the doped ytterbium ions can emit single-mode signal laser light, and the first pump laser P1 corresponding to the doped ytterbium ions can absorb more mode pump laser, and the output peak of ytterbium ion can be basically 1080nm, and its absorption peak can be basically 915nm or 976nm; that is, the peak wavelength of the first signal laser is basically 1080nm, and the peak wavelength of the first pump laser is basically 915nm or Basic 976nm.

Preferably, the second rare earth ion material may be an erbium-ytterbium co-doped ion material, the second signal laser L2 corresponds to the single-mode signal laser emitted by the doped erbium ions, and the second pump laser P2 corresponds to the erbium-ytterbium doped co-doped ions For the absorbed multi-mode pump laser, the output peak of the erbium-ytterbium co-doped ion can be basically 1550nm, and its optional absorption peak can be basically 940 or 980nm; that is, the peak wavelength of the second signal laser is basically 1550nm, and the second pump laser The peak wavelength is substantially 940nm or substantially 980nm.

Preferably, the third rare earth ion material can be a doped thulium ion material, the third signal laser L3 corresponds to the single-mode signal laser emitted by the doped thulium ions, and the third pump laser P3 corresponds to the doped thulium ions absorbed For multimode pump laser, the output peak of doped thulium ions can be basically 1940nm or basically 1980nm, and its optional absorption peak can be basically 793nm or 1550nm; that is, the second signal laser peak wavelength can be basically 1940nm or basically 1980nm, the second pump The peak wavelength of the pump laser may be substantially 793 nm or 1550 nm.

Preferably, the nth rare earth doped ion material can be other doped ion materials available for fiber lasers, and the nth signal laser Ln and the nth pump laser Pn correspond to the single-mode signal emitted and absorbed by the nth rare earth doped ion Laser and multimode pump lasers.

A beam-condensing area is set on the rear side of the beam-concentration area: in order to realize low insertion loss coupling between the beam-concentration area and the multi-core doped active fiber, the beam-condensing area needs to be taper-drawn.

Preferably, the beam-condensing region 3 is obtained by subjecting the signal light and the pump light to the output fiber-condensing region 2 through a conicing process.

In order to reduce the loss of light energy, preferably, the length of the taper satisfies the insulating taper condition: the diffraction angle in the fiber ≥ the fiber taper angle.

Preferably, the taper ratio of this section is: 2:1.

Preferably, for efficient coupling, after the fiber is tapered, the taper end is cut, and after it is cut, it is spliced with the multi-core doped active fiber. The welding method can be CO2 laser, electrode discharge, hydrogen-oxygen Flame, graphite heating and other welding methods are used for welding.

Preferably, the cleaving of the tapered end can be performed with an optical fiber cleaving knife.

In order to match the bundling area, the multi-core doped active fiber includes a plurality of doping parts, that is, when the bundling area includes a plurality of parts, that is, m parts, the multi-core doped active fiber includes the same number, that is, m doping parts. part.

The bundling area includes three parts, namely the first part of the bundling area, the second part of the bundling area, and the third part of the bundling area.

The multi-core doped active fiber includes a plurality of rare earth ion doped regions, preferably, at least two rare earth ion doped regions. Preferably, there is a central rare-earth ion-doped region in the innermost layer, and an annular region can be used as the outer-layer rare-earth-ion-doped region. The rare earth ion-doped region of the outer layer adopts an annular region, preferably, at least one central doped ion region and an annular rare-earth ion-doped region. That is, multi-core in a multi-core doped active fiber refers to an amplification region having at least two doped rare earth ions. Preferably, the multi-core doped active fiber includes three regions doped with rare earth ions. Preferably, the multi-core doped active fiber includes a central region doped with rare earth ions and two annular regions doped with rare earth ions.

Preferably, it can be mainly composed of three parts: 1, 2, and 3. The third region is a region doped with rare earth thulium ions, preferably a substantially annular region, the second region 2 is a region doped with rare earth erbium ytterbium ions, preferably a substantially annular region, and the first region is doped with ytterbium ions area, preferably a substantially circular area. The inner diameter of the third region is 362.5 μm, and the outer diameter of the third region is 487.5 μm. The inner diameter of the second region was 212.5 μm, and the outer diameter of the second region was 337.5 μm. The inner diameter of the first doped region is 62.5 μm, and the outer diameter of the first doped region is 187.5 μm. The composition of parts 4, 5, 6, and 7 is quartz.

The first region is substantially a circular region, doped with first rare earth ions for amplifying the first signal light; the second region surrounds the first region, and the second region is substantially a (circular) annular region, doped with second rare earth ions , used for amplifying the second signal light; the third region surrounds the second region, the second region is a substantially (circular) annular region, and is doped with third rare earth ions for amplifying the third signal light.

That is, a quartz layer is arranged between the first area and the second area, and the thickness of the quartz layer is preferably the inner diameter of the second area minus the outer diameter of the first area, that is, the thickness of one side is 12.5 μm, and the thickness of both sides is added. is 25 μm.

A quartz layer is arranged between the second region and the third region, the thickness of the quartz layer is preferably the inner diameter of the third region minus the outer diameter of the second region, the thickness of one side is 12.5 μm, and the thickness of both sides is 25 μm together .

A quartz layer is provided outside the third region, and the thickness of the quartz layer is preferably 12.5 μm on one side and 25 μm in total on both sides.

A quartz core region is arranged inside the first region, the quartz core region is substantially a circular region, and the diameter of the quartz core region is substantially the inner diameter of the first doping region.

According to the design, the refractive index of the quartz layer is lower than the refractive index of the first region, the refractive index of the quartz layer is lower than the refractive index of the second region, the refractive index of the quartz layer is lower than the refractive index of the third region, preferably, the quartz core region The index of refraction is lower than the index of refraction of the first doped region.

Preferably, the middlemost optical fiber in the first part of the bundling area is preferably a pumping optical fiber.

Preferably, in the multi-wavelength amplified ring laser output by the multi-core doped active fiber, the first signal light L1, the first pump light P1 and the output laser part corresponding to the first region are the first output light part Q1; The output laser part corresponding to the second signal light L2 and the second pump light P2 and the second region is the second output light part Q1; the output laser part corresponding to the third signal light L3 and the third pump light P3 and the third region is The third output light part Q3; when the part of the bundle area exceeds 3 parts, the output laser part corresponding to the nth signal light Ln, the nth pump light Pn and the nth region is the nth output light part Qn (n>3 , is a positive integer).

Through the design of the fiber structure, the number of core regions of the multi-core doped fiber can be increased to increase the doping rare earth ion species, such as: neodymium, holmium, samarium, praseodymium, etc.

Preferably, the signal fiber is selected as a few-mode fiber with a core diameter greater than 15 μm and a cladding diameter greater than 150 μm. Preferably, the pump fiber is selected as a multimode fiber with a core diameter greater than 133 μm and a cladding diameter greater than 153 μm.

The beneficial effects of the present invention are:

(1) The structure of the multi-layer fiber core is creatively transformed, and the designed fiber bundle structure and the unique multi-core doped fiber are cleverly combined to provide a composite wavelength ring-spot laser output laser. The coupling efficiency of the input pump light is high, the mode of the input signal is more stable, and the spatial distribution of the input signal is more uniform, which can greatly improve the laser power and greatly reduce the energy loss. At the same time, the rationalized structural arrangement makes the beam quality of the output light higher, the mode is more stable, the nonlinear effect is reduced, and the needs of high-power laser processing are met.

(2) It can carry out high-energy multi-wavelength laser ring output, which meets the requirements of some specific processing application scenarios in high-power laser processing, such as some scenarios in precision welding, etc., and realizes ring-shaped multi-wavelength composite laser output, with good When the number and types of output wavelengths need to be adjusted, complex settings and structures do not need to be changed. It is only necessary to turn on or off the signal laser and pump laser of the corresponding wavelength to replace it with another one with center symmetry. homogeneous ring laser.

(3) A quartz low-refractive index layer is arranged in the bundle area, the multi-core doped active fiber includes a plurality of annular rare-earth ion-doped regions, and a quartz layer is arranged between any two rare-earth-doped ion regions to reduce the Interference between the part of the cluster area and each rare earth ion doped area and improve the utilization rate of the laser; a quartz layer is arranged outside the outermost rare earth ion doped area to prevent laser leakage from causing harm to people.

(4) Set the wavelength of the signal laser located in the inner layer to be smaller than the wavelength of the signal laser located in the outer layer, then the pump laser or excitation light energy occasionally overflowing from the inner layer can also be absorbed by the rare earth ions in the outer layer, improving the pumping light. The utilization of energy not only reduces the cost at high energy output, but also reduces the heat generation and heat load of the entire gain fiber, preventing nonlinear effects caused by overheating.

(5) According to the design of the fiber structure, there is a numerical aperture in each region. At the same time, each kind of thulium, erbium-ytterbium, ytterbium laser that needs to be amplified and the corresponding pump laser are restricted to transmit in the 1, 2, and 3 regions, respectively. Therefore, the amplification of the above three lasers is spatially separated. Therefore, the output of each of the above lasers can be controlled by controlling the injection size of the signal light and the pump light in the 1, 2, and 3 regions. The amplifying structure is essentially a Mopa amplifying structure, so it has the characteristic that the amplified output laser depends on the beam quality of the signal laser. In the present invention, single-mode laser of thulium, erbium and ytterbium is used as the signal light, so that the output of high beam quality and high output power can be obtained.

(6) The inventor can replace the signal fiber with a few-mode laser fiber to solve the problem of mode mismatch in the pumping process. At the same time, both the core diameter of the few-mode signal fiber and the core diameter of the multi-mode pump fiber can be increased. Through the design of the fiber structure, the number of core regions of the multi-core doped fiber can be increased to increase the doping rare earth ion species, such as: neodymium, holmium, samarium, praseodymium, etc.

(7) There are at least three parts of the clustering area, that is, the clustering area should at least include the first part of the clustering area, the second part of the clustering area, and the third part of the clustering area. Compared with the case of only two parts, when the clustering area includes three parts In some cases and above, it can simply control the output of various combinations of laser wavelength ring output, such as the combination of the second signal light and the third signal light, the combination of the first signal light and the third signal light (this combination still has a larger The spatially separated composite laser has a good application in precision cladding processing), the first signal light and the second signal light, the first signal light and the second signal light and the third signal light, etc., so that you can Simple and quick operations can realize more processing functions, and at the same time can greatly increase the power of the total output light, which greatly exceeds the power level and functionality of the ring laser output of the prior art.

Description of drawings

Figure 1 is a schematic structural diagram of the present invention.

FIG. 2 is a schematic cross-sectional view of the signal light and pump light output fiber bundle area of the present invention.

FIG. 3 is a schematic cross-sectional view of a specific embodiment of the signal fiber and the pump fiber of the present invention.

4 is a schematic cross-sectional view of the multi-core doped active fiber of the present invention.

Detailed ways

The technical solutions of the present invention are further described below with reference to the accompanying drawings and through specific embodiments.

As shown in FIG. 1 , the present invention discloses a multi-doped rare-earth ion multi-wavelength fiber laser, which can realize high-power composite wavelength fiber laser output whose output power is individually controllable by multiple wavelengths.

The composite wavelength fiber laser uses a multi-core doped active fiber as a gain fiber, and combines the signal light + pump light combiner to realize the amplified output of the signal light (as shown in Figure 1).

The composite wavelength fiber laser mainly includes four parts: signal light and pump light module, signal light and pump light output fiber bundle area, bundle taper area, and multi-core doped active fiber.

The signal light and pump light module includes a signal light module and a pump light module. The signal light module can output the signal laser to be amplified, preferably, the signal light module can output the signal laser to be amplified with two wavelengths at the same time, namely the first signal laser L1 and the second signal laser L2, the first signal laser L1 and the second signal laser L2 respectively. Or L1 and the second signal laser L2 can be respectively output from the signal light module through the respective waveguide output structures or spatial light output structures; preferably, the signal light module can simultaneously output three wavelengths of signal lasers to be amplified, which are A signal laser L1, a second signal laser L2, a third signal laser L3, the first signal laser or L1, the second signal laser L2, and the third signal laser L3 can respectively pass through the respective waveguide output structures or spatial light output structures from the signal Optical module output; preferably, the signal optical module can simultaneously output n kinds of wavelengths (n>3, a positive integer) of the signal laser to be amplified, which are the first signal laser L1, the second signal laser L2, and the third signal respectively. Laser L3, (fourth signal laser L4)...nth signal laser Ln, first signal laser L1, second signal laser L2, third signal laser L3, (fourth signal laser L4)...nth signal laser Ln It can be output from the signal light module through respective waveguide output structures or spatial light output structures, respectively.

The pump optical module outputs the corresponding pump light required to realize the signal light amplification. Preferably, the pump light includes pump lasers of multiple wavelengths corresponding to the signal light of multiple wavelengths. Preferably, when the signal optical module can When outputting two wavelengths of signal lasers to be amplified at the same time, which are the first signal laser L1 and the second signal laser L2, respectively, the pump optical module outputs the corresponding pump lights of the two wavelengths, which are the first pumping laser light respectively. P1 and the second pump laser P2; preferably, the signal optical module can simultaneously output three wavelengths of the signal laser to be amplified, which are the first signal laser L1, the second signal laser L2, and the third signal laser L3, respectively, The pump optical module outputs corresponding pump lights of three wavelengths, namely the first pump laser P1, the second pump laser P2, and the third pump laser P3; preferably, the signal optical module can output n wavelengths at the same time (n>3, is a positive integer), the signal lasers to be amplified are respectively the first signal laser L1, the second signal laser L2, the third signal laser L3, (the fourth signal laser L4)...the nth signal laser At Ln, the pump optical module outputs corresponding pump lights of n wavelengths, which are the first pump laser P1, the second pump laser P2, the third pump laser P3...the nth pump laser Pn.

The signal laser corresponds to the laser that can be emitted and/or amplified by the multi-core fiber doped rare-earth ion material, and the pumping laser is the pumping laser that the rare-earth ions can absorb and invert the number of ions. Preferably, the first signal laser L1 corresponds to the first pump laser P1, and the first rare-earth ion material absorbs the first pump laser P1 and inverts the number of ions, and outputs the amplified first signal laser L1; preferably, the second signal The laser L2 corresponds to the second pump laser P2, and the second rare earth ion material absorbs the second pump laser P2 and makes the number of ions reversed, and outputs the amplified second signal laser L2; preferably, the third signal laser L3 corresponds to the third pump The pump laser P3, the third rare earth ion material absorbs the third pump laser P3 and inverts the number of ions, and outputs the amplified third signal laser L3; preferably, the nth signal laser Ln corresponds to the nth pump laser Pn, and the nth signal laser Ln The rare-earth ion material absorbs the nth pump laser Pn and inverts the number of ions, and emits the amplified nth signal laser Ln (n>3, which is a positive integer).

Preferably, the powers of the first pump laser, the second pump laser, the third pump laser...the nth signal laser are independently adjustable, that is, the power of the first pump laser is independently adjustable, that is, the second pump laser is independently adjustable. The power of the pump laser is independently adjustable, that is, the power of the third pump laser is independently adjustable, that is, the power of the nth pump laser is independently adjustable (n>3, a positive integer), so that the output light of each wavelength can be independently adjustable. control.

Preferably, the signal laser can be a single-mode signal laser to improve the beam quality of the output light.

Preferably, the pump laser can be a multi-mode pump laser, so that rare earth ions everywhere in the gain material can be well-balanced excitation and extended power scenarios.

The signal light and pump light output fiber bundling area includes the signal fiber and the pump fiber (as shown in FIG. 2 ), which bundles the signal fiber and the pump fiber. Preferably, in order to stably fix the signal fiber and the pump fiber in a bundle, a tube is also included for enclosing the signal fiber and the pump fiber. In order to facilitate subsequent taper drawing, the tube used to surround the signal fiber and the pump fiber is a quartz glass tube.

For convenience, the bundle area of the output fibers of the signal light and the pump light is referred to as bundle area below.

Preferably, since the energy of the pumping light is very large, the cladding of the pumping fiber is relatively thin, in order to reduce the loss of light energy and improve the optical efficiency, the quartz glass tube is a low-refractive-index quartz glass tube, and a low-refractive index is used. The high-efficiency quartz glass tube can well bind the pump light in the glass tube in the subsequent taper region to prevent the light from being lost. The low refractive index in the low-refractive-index quartz glass tube means that the refractive index of the quartz glass tube is lower than The core refractive index of the pump fiber (here lower than the core refractive index of the pump fiber means lower than the core refractive index of all pump fibers). At the same time, although the energy of the signal light is low and the cladding of the signal fiber is thick, the probability of loss of the signal light is not high, but due to the subsequent taper drawing, the signal light may still be lost in the taper region. Therefore, it is better to confine the signal light better, and preferably the refractive index of the quartz glass tube is also lower than the core refractive index of the signal fiber (here, lower than the core refractive index of the signal fiber means that it is lower than all signals the core refractive index of the fiber).

Preferably, the silica low refractive index glass tube can be manufactured by doping, preferably, in order to better match the optical fiber in the taper region, preferably, the silica low refractive index glass tube is fluorine-doped or boron silica low Refractive index glass tube.

Preferably, the signal fiber can be a single-mode fiber to obtain single-mode signal light with high beam quality. Preferably, the signal fiber is a 10/125 single-mode fiber (as shown in FIG. 3 ).

Preferably, the pump fiber adopts a multi-mode pump fiber that can accommodate high-power multi-mode light. Preferably, the pump fiber is a parameter of 105/125/0.22 (as shown in Figure 3). The injection capability of the pump laser will be increased.

Preferably, in order to make different laser sub-regional pumping to improve the pumping efficiency, the bundle area is divided into a plurality of area parts, preferably, it may include the first part of the bundle area and the second part of the bundle area; preferably, it may include the first part of the bundle area One part, the second part of the clustering area, the third part of the clustering area; preferably, it may include the first part of the clustering area, the second part of the clustering area, the third part of the clustering area, and the nth part of the clustering area.

Preferably, each part includes a signal fiber and a pump fiber.

Preferably, in order to better transmit the signal light and improve the quality of the output signal laser, the signal laser and the active fiber are more matched. .

Preferably, the pump fiber is a pump source coupling output fiber in the pump optical module.

Preferably, when multi-wavelength lasers are output, in high-power application scenarios, such as welding and other scenarios, multi-wavelength lasers are often required to have the same output axis. The wavelength component laser can be individually controlled, so that when only part of the multi-wavelength laser is used, the output laser should have the same axis and symmetrical distribution. The parts are laid out layer by layer starting from the center and outward.

Preferably, the bundling area has the first part of the bundling area, the second part of the bundling area, the third part of the bundling area, ... the nth area of the bundling area (n>3, a positive integer) from the inside to the outside.

Preferably, the first part of the bundling area is a circular area in the center, the second part of the bundling area is an annular area surrounding the first part of the bundling area, the third part of the bundling area is an annular area surrounding the second part of the bundling area, ... The nth part (n>3, which is a positive integer) is an annular area surrounding the (n-1)th part of the bundle area.

Preferably, in order to achieve high-quality laser output, the second part of the bundling area is an annular area surrounding the first part of the bundling area, the third part of the bundling area is an annular area surrounding the second part of the bundling area, ... The nth part (n>3, which is a positive integer) is an annular area surrounding the (n-1)th part of the bundle area.

Each portion of the bundle preferably includes a respective signal fiber and its corresponding pump fiber.

Preferably, the first part of the bundle area includes a first signal fiber and a corresponding first pump fiber, the first signal fiber is used for transmitting the first signal laser L1, the first pump fiber is used for transmitting the first pump laser P1, Preferably, the number of first signal fibers is one or more, preferably, the number of first signal fibers is two or more, preferably, the number of first pump fibers is one or more, preferably, the number of first pump fibers is The number is two or more; preferably, the second part of the cluster area includes a second signal fiber and a corresponding second pump fiber, the second signal fiber is used for transmitting the second signal laser L2, and the second pump fiber is used for For transmitting the second pump laser P2, preferably the number of the second signal fibers is one or more, preferably, the number of the second signal fibers is two or more, preferably, the number of the second pump fibers is one or more, Preferably, the number of the second pump fibers is two or more; preferably, the third part of the bundle area includes a third signal fiber and a corresponding third pump fiber, and the third signal fiber is used to transmit the third signal laser L3 , the third pump fiber is used to transmit the third pump laser P3, preferably the number of the third signal fibers is one or more, preferably, the number of the third signal fibers is two or more, preferably, the third pump The number of optical fibers is one or more, preferably, the number of third pump fibers is two or more; Used to transmit the nth signal laser Ln, the nth pump fiber is used to transmit the nth pump laser Pn, preferably the number of the nth signal fiber is one or more, preferably, the number of the nth signal fiber is two or more , preferably, the number of the nth pumping fibers is one or more, and preferably, the number of the nth pumping fibers is two or more.

Preferably, the part of the cluster area should be at least more than two, that is, the cluster area should at least include the first part of the cluster area, the second part of the cluster area, and the third part of the cluster area (refer to the embodiment of FIG. 2 ), as opposed to only two In the case of part (that is, only including the first part of the cluster area and the second part of the cluster area), when the cluster area includes three or more parts, it can simply control the ring output of various combinations of laser wavelengths (instead of two parts). There is only one combination), such as the combination of the second signal light and the third signal light, the combination of the first signal light and the third signal light (this combination is also a composite laser with greater spatial separation, and is used in precision cladding. It has a good application in processing occasions), the first signal light and the second signal light, the first signal light and the second signal light and the third signal light, etc., so that more processing functions can be realized with simple and fast operation. At the same time, the power of the total output light can be greatly improved, which greatly exceeds the power level and functionality of the ring laser output of the prior art.

Preferably, the first rare earth ion material corresponding to the first signal laser L1 and the first pump laser P1 can be selected from ytterbium-doped material, erbium-doped material, thulium-doped material, neodymium-doped material, holmium-doped material, samarium-doped material, praseodymium-doped material One of the materials, erbium-ytterbium co-doped materials, etc.

Preferably, the second rare earth ion material corresponding to the second signal laser L2 and the second pump laser P2 can be selected from ytterbium-doped material, erbium-doped material, thulium-doped material, neodymium-doped material, holmium-doped material, samarium-doped material, praseodymium-doped material One of the materials, erbium-ytterbium co-doped materials, etc. Preferably, the second rare earth ion material should be different from the first rare earth ion material, so as to emit different wavelengths that can be controlled by the annular layer, ie, the wavelength of the second signal laser L2 is different from that of the first signal laser L1.

Preferably, the third rare earth ion material corresponding to the third signal laser L3 and the third pump laser P3 can be selected from ytterbium-doped material, erbium-doped material, thulium-doped material, neodymium-doped material, holmium-doped material, samarium-doped material, praseodymium-doped material One of the materials, erbium-ytterbium co-doped materials, etc. Preferably, the third rare-earth ion material should be different from the first rare-earth ion material, and the third rare-earth ion material is different from the second rare-earth ion material, so as to emit different wavelengths that can be controlled by the annular layer, that is, the third signal laser L3 The wavelength of the laser light is different from the wavelength of the second signal laser light L2, that is, the wavelength of the third signal laser light L3 is different from the wavelength of the first signal laser light L1.

Preferably, the nth rare earth ion material corresponding to the nth signal laser Ln and the nth pump laser Pn can be selected from ytterbium-doped material, erbium-doped material, thulium-doped material, neodymium-doped material, holmium-doped material, samarium-doped material, praseodymium-doped material One of the materials, erbium-ytterbium co-doped materials, etc. Preferably, the nth rare earth ion material should be different from the rare earth ion material corresponding to other parts of the signal laser and pump laser in the beam area, so as to emit different wavelengths that can be controlled by the annular layer.

Since the arrangement of each active doping region in the multi-core doped active fiber preferably corresponds to the arrangement pattern of each part of the bundled region, therefore, the various doping regions in the multi-core doped active fiber Zones are also arranged layer by layer starting from the center and outward. In the process of high-energy laser pumping, in the taper region and the multi-core doped active fiber, the pump light and excitation light in the inner region will be more easily dissipated to the outside, so it is easy to cause the pump light waste and reduce laser efficiency. Therefore, in order to improve the utilization efficiency of the pump light and improve the laser efficiency, preferably, each part of the bundle area can be set in the following way: the wavelength of the pump light in the part of the bundle area located in the relatively inner layer is smaller than the wavelength of the pump light located in the relatively The wavelength of the pump light in the part of the cluster region of the outer layer; the wavelength of the first pump laser P1 in the inner layer is smaller than the wavelength of the second pump laser P2 located in the second part of the cluster region around it; located in the second part of the cluster region The wavelength of the second pump laser P2 is smaller than the wavelength of the third pump laser P3 in the third part of the cluster region; the wavelength of the pump laser P(n-1) located in the (n-1)th part of the cluster region is smaller than the wavelength of the pump laser P(n-1) located in the third part of the cluster region The wavelength of the pump laser Pn in the nth part of the region (n>3, being a positive integer); and/or, the wavelength of the signal light in the part of the bundle in the relatively inner layer is smaller than that in the part of the bundle in the relatively outer layer around it The wavelength of the signal light, the wavelength of the first signal laser L1 in the inner layer is less than the wavelength of the second signal laser L2 located in the second part of the cluster area around it; the wavelength of the second signal laser L2 located in the second part of the cluster area is less than The wavelength of the third signal laser L3 in the third part of the bundle area; the wavelength of the signal laser L(n-1) located in the (n-1) part of the bundle area is smaller than the wavelength of the pump laser Pn located in the nth part of the bundle area ( n>3, which is a positive integer). Since the wavelength of the pump laser in the inner layer is smaller than the wavelength of the pump laser in the outer layer, and or, the wavelength of the signal laser in the inner layer is smaller than the wavelength of the signal laser in the outer layer, the pump laser that occasionally overflows in the inner layer or The excitation light energy can also be absorbed by the rare earth ions in the outer layer, which improves the utilization rate of the pump light energy, not only reduces the cost at high energy output, but also reduces the heat generation and heat load of the entire gain fiber, preventing the undesired effect caused by overheating. Linear effect. At the same time, the above arrangement can also take into account the reasonable distribution of the laser modes in the multi-core doped active fiber.

Preferably, the following specific embodiments can be selected to realize the above-mentioned concept.

Preferably, the signal fiber in the first part of the bundle area is a passive matching fiber capable of transmitting corresponding laser light excited by doped ytterbium ions.

Preferably, the pumping fiber of the first part of the bundle region is a coupling-out fiber of a pumping source outputting laser light capable of pumping the ytterbium ion-doped material. Preferably, the pump source is a laser diode (LD) pump source, which outputs a pump laser that can pump the ytterbium-doped material.

Preferably, the signal fiber in the second part of the bundle area is a passive matching fiber capable of transmitting corresponding laser light excited by doped erbium ions.

Preferably, the pumping fiber of the second part of the bundle area is a coupling-out fiber of a pumping source outputting laser light capable of pumping the erbium-ytterbium co-doped ion material. Preferably, the pump source is a laser diode (LD) pump source, which outputs a pump laser capable of pumping the erbium-ytterbium co-doped ion material.

Preferably, the signal fiber in the third part of the bundle area is a passive matching fiber capable of transmitting corresponding laser light excited by doped thulium ions.

Preferably, the pumping fiber in the third part of the bundle region is a coupling-out fiber of a pumping source outputting laser light capable of pumping the thulium ion-doped material. Preferably, the pump source is a laser diode (LD) pump source, which outputs a pump laser capable of pumping the thulium ion material.

Preferably, when there is the nth part of the bundle area (n>3, which is a positive integer), appropriate signal fibers, pump fibers and pump sources can be selected.

Since the absorption peak of the doped ytterbium ion material is 915nm or 976nm under normal conditions, and the output peak is 1080nm, the absorption peak of the erbium-ytterbium co-doped ion material is 940nm or 980nm under normal conditions, the output peak is 1550nm, and the thulium ion-doped material has an absorption peak of 940nm or 980nm. The absorption peak of the material under normal conditions can be basically 793nm or 1550nm, and the output peak is 1940nm or 1980nm, which meets the requirements of the above-mentioned pump light and excitation light wavelengths. Improve energy utilization, reduce heat generation, and take into account the requirements of reasonable distribution of laser modes in multi-core doped active fibers.

The inventor realizes that in the beam-concentration taper region, the possibility of laser overflow from the fiber cladding increases due to the fiber taper. If the overflowed pump light can be totally reflected at the interface between the cladding and the quartz glass tube. , then the pump light will be better restrained, preventing the pump light from entering other regions and affecting the properties of other regions. Therefore, in order to prevent interference and improve the use efficiency of the pump light, the pump light caused by the taper is removed from the The interface between the cladding of the pump fiber and the silica glass tube reflects back, preferably, the refractive index of the silica low-refractive index glass tube is lower than the cladding refractive index of the pumping fiber (here lower than the cladding refractive index of the pumping fiber). is lower than the cladding index of all pump fibers).

Likewise, if considering the risk of interference caused by the leakage of signal light, preferably, the refractive index of the silica low-refractive index glass tube is lower than the cladding refractive index of the signal fiber (here lower than the cladding refractive index of the signal fiber). ratio refers to the refractive index below the cladding of all signal fibers).

On the basis of the above, in order to reduce the interference between the laser beams of each layer in the beam-concentration area and the beam-condensing area, and further improve the energy utilization rate and the output laser quality, preferably, quartz low-refractive-index glass is arranged between each part of the beam-concentration area. Tube. For example, a quartz low-refractive-index glass tube is arranged between the first part of the bundling area and the second part of the bundling area; a quartz low-refractive index glass tube is arranged between the second part of the bundling area and the third part of the bundling area; A quartz low-refractive index glass tube is arranged between the n-1) part and the nth part of the concentrating area. Of course, in addition to this, the outermost part of the output fiber bundle area of the signal light and the pump light includes a quartz low-refractive index glass tube, which has been described before and will not be repeated here. Preferably, the quartz low refractive index glass tube is a fluorine-doped low refractive index glass tube.

Specific embodiments are described below. The cluster area includes the first part of the cluster area, the second part of the cluster area, and the third part of the cluster area; the first part of the cluster area is basically a circular area (corresponding to area c in FIG. 2 ), and the The outer diameter is basically 375 μm; the second part of the bundling area is basically an annular area (corresponding to area b in FIG. 2 ), preferably, the second part of the bundling area is basically an annular area, and the inner diameter of the second part of the bundling area is 425 μm, The outer diameter of the second part of the bundling area is 675 μm; the third part of the bundling area is basically an annular area (corresponding to the area a in FIG. 2 ), preferably, the third part of the bundling area is basically a circular area, and the third part of the bundling area is basically an annular area. The inner diameter of the part is 725 μm, and the outer diameter of the third part of the bundle area is 975 μm (both inner diameter and outer diameter mentioned above refer to diameter).

In a specific embodiment, for example, the quartz low-refractive index glass tube between the first part of the concentrating area and the second part of the concentrating area corresponds to the f region in FIG. 2 , and the thickness of the fluorine-doped low-refractive index glass tube in the f region is preferably The ground is 25 μm. The quartz low-refractive-index glass tube between the second part of the bundling area and the third part of the bundling area corresponds to the e-region in FIG. 2 , and the thickness of the fluorine-doped low-refractive-index glass tube in the e-region is preferably 25 μm. The quartz low-refractive-index glass tube outside the third part of the bundle area corresponds to the area d in FIG. 2 , and the thickness of the fluorine-doped low-refractive index glass tube in the d area is preferably 25 μm. Its function is to limit the transmission of signal and pump light in each area of a, b and c, which can ensure that both signal and pump light can be transmitted in the area where it is located, and no signal and pump between different areas are generated. The problem of laser cross transmission.

Since the wavelengths corresponding to the pumping and output of the laser cannot be exact and accurate values, they are all close to a certain value, so the following description is often described as "basic" as a certain wavelength.

Preferably, the first rare earth ion material may be a material doped with ytterbium ions, the first signal laser L1 corresponding to the doped ytterbium ions can emit single-mode signal laser light, and the first pump laser P1 corresponding to the doped ytterbium ions can absorb more mode pump laser, and the output peak of ytterbium ion can be basically 1080nm, and its absorption peak can be basically 915nm or 976nm; that is, the peak wavelength of the first signal laser is basically 1080nm, and the peak wavelength of the first pump laser is basically 915nm or Basic 976nm.

Preferably, the second rare earth ion material may be an erbium-ytterbium co-doped ion material, the second signal laser L2 corresponds to the single-mode signal laser emitted by the erbium-doped co-doped ions, and the second pump laser P2 corresponds to the erbium-ytterbium-doped co-doped ion material. For the multi-mode pump laser absorbed by the doped ions, the output peak of the erbium-ytterbium co-doped ion can be basically 1550nm, and its optional absorption peak can be basically 940 or 980nm; that is, the second signal laser peak wavelength is basically 1550nm, the second pump The peak wavelength of the pump laser is substantially 940 nm or substantially 980 nm.

Preferably, the third rare earth ion material can be a doped thulium ion material, the third signal laser L3 corresponds to the single-mode signal laser emitted by the doped thulium ions, and the third pump laser P3 corresponds to the doped thulium ions absorbed For multimode pump laser, the output peak of doped thulium ions can be basically 1940nm or basically 1980nm, and its optional absorption peak can be basically 793nm or 1550nm; that is, the second signal laser peak wavelength can be basically 1940nm or basically 1980nm, the second pump The peak wavelength of the pump laser may be substantially 793 nm or 1550 nm.

Preferably, the nth rare earth doped ion material can be other doped ion materials available for fiber lasers, and the nth signal laser Ln and the nth pump laser Pn correspond to the single-mode signal emitted and absorbed by the nth rare earth doped ion Laser and multimode pump lasers.

A beam-condensing area is set on the rear side of the beam-concentration area: in order to realize low insertion loss coupling between the beam-concentration area and the multi-core doped active fiber, the beam-condensing area needs to be taper-drawn.

Preferably, the beam-condensing region 3 is obtained by subjecting the signal light and the pump light to the output fiber-condensing region 2 through a conicing process.

In order to reduce the loss of light energy, preferably, the length of the taper satisfies the insulating taper condition: the diffraction angle in the fiber ≥ the fiber taper angle.

Preferably, the taper ratio of this section is: 2:1.

Preferably, for efficient coupling, after the fiber is tapered, the taper end is cut, and after it is cut, it is spliced with the multi-core doped active fiber. The welding method can be CO2 laser, electrode discharge, hydrogen-oxygen Flame, graphite heating and other welding methods are used for welding.

Preferably, the cleaving of the tapered end can be performed with an optical fiber cleaving knife.

In order to match the bundling region, the multi-core doped active fiber includes a plurality of different doped sections, that is, when the bundling region includes m sections, the multi-core doped active fiber includes m doped sections; for example, when When the bundling area includes 4 parts, namely the first part of the bundling area, the second part of the bundling area, the third part of the bundling area, and the fourth part of the bundling area, the multi-core doped active fiber also includes 4 doped parts; when When the bundling area includes three parts, that is, the first part of the bundling area, the second part of the bundling area, and the third part of the bundling area, the multi-core doped active fiber also includes three doped parts.

FIG. 4 is a specific embodiment, which corresponds to the embodiment of the bundle area of FIG. 2 .

In the embodiment corresponding to FIG. 4 , the bundling area includes three parts, namely, the first part of the bundling area, the second part of the bundling area, and the third part of the bundling area.

The multi-core doped active fiber includes a plurality of rare earth ion doped regions, preferably, at least two rare earth ion doped regions. Preferably, there is an innermost central rare-earth-doped region, and an outer rare-earth-doped region can be a ring-shaped region. For better symmetry and optical fiber mode matching, the most central rare-earth-doped region is a basic circle. The other rare earth ion doped regions, ie the outer rare earth ion doped regions, are annular regions, that is, preferably, at least one central doped ion region and an annular rare earth ion doped region. That is, multi-core in a multi-core doped active fiber refers to an amplification region having at least two doped rare earth ions. Preferably, the multi-core doped active fiber includes three regions doped with rare earth ions. Preferably, the multi-core doped active fiber includes a central region doped with rare earth ions and two annular regions doped with rare earth ions. Compared with the method of multiple discrete circular cores, the method of stacked annular regions greatly improves the space utilization of laser pumping, improves the energy of laser output, has good economic advantages in the field of high-power laser output, and is conducive to heat dissipation , to reduce the occurrence of nonlinear effects.

Specifically, the description will be made with reference to FIG. 4 . Preferably, the multi-core doped active fiber can be mainly composed of three parts 1, 2 and 3 from the cross section. The third region 1 is a region doped with rare earth thulium ions, preferably a substantially annular (circular) region, and the second region 2 is a region doped with rare earth erbium ytterbium ions, preferably substantially annular (circular) The first region (comprising 3 and 6) is a region doped with ytterbium ions, preferably a substantially circular region. The inner diameter of the third region 1 is 362.5 μm, and the outer diameter of the third region 1 is 487.5 μm. The inner diameter of the second region 2 is 212.5 μm, and the outer diameter of the second region 2 is 337.5 μm.

In order to obtain all the light wavelengths of all the light output in a circular ring shape, preferably, the first region includes a central quartz region 6 with undoped rare earth ions located in the center and a first doped region 3 whose outer layer is in the shape of a circular ring. ; At this time, the fiber with the first part in the center of the cluster region is preferably the pump fiber, which is beneficial to the omnidirectional pumping of the pump laser in the first doped region (because the center does not emit excitation light, if the center For the signal fiber, it will not have any beneficial effect, which will reduce the excitation efficiency), improve the excitation efficiency, and reduce energy loss.

At this time, the inner diameter of the first doped region 3 is 62.5 μm, and the outer diameter of the first doped region 3 is 187.5 μm. The composition of parts 4, 5, 6, and 7 is quartz. Of course, if the light field section of the laser wavelength at the center of the final output laser needs to be circular, then the first region may not include the central region 6 of undoped rare earth ions, and the first region only includes the first doped region 3, The first doped region 3 is circular.

The first region is substantially a circular region, doped with first rare earth ions for amplifying the first signal light; the second region surrounds the first region, and the second region is a substantially annular (circular) region, doped with second The rare earth ions are used for amplifying the second signal light; the third region surrounds the second region, the second region is a substantially annular (circular) region, and the third rare earth ions are doped for amplifying the third signal light. The multi-core doped active fiber includes a rare-earth-doped region in the center and one or more annular (annular) rare-earth-doped regions on the outside, preferably, quartz is arranged between any two rare-earth-doped regions The layer is used to isolate the laser light, and preferably, a quartz layer is arranged outside the rare earth ion-doped region of the outermost layer to prevent laser leakage from causing harm to people.

A quartz layer 7 is arranged between the first area and the second area 2, and the thickness of the quartz layer is preferably the inner diameter of the second area minus the outer diameter of the first area 3, that is, the thickness of one side is 12.5 μm, and the thickness of both sides is 12.5 μm. Add up to 25µm.

A quartz layer 5 is arranged between the second area 2 and the third area 1, the thickness of the quartz layer is preferably the inner diameter of the third area 1 minus the outer diameter of the second area 2, the thickness of one side is 12.5 μm, and the thickness of both sides is 12.5 μm. The thicknesses add up to 25 μm.

A quartz layer 4 is provided outside the third region 1 , and the thickness of the quartz layer is preferably 12.5 μm on one side and 25 μm in total on both sides.

Preferably, a quartz core region (ie, central quartz region) 6 is provided inside the first region, the quartz core region 6 is substantially a circular region, and the diameter of the quartz core region 6 is substantially the inner diameter of the first doped region 3 .

According to the design, the refractive index of the quartz layer and the quartz core is lower than the refractive index of the first region, the refractive index of the quartz layer is lower than the refractive index of the second region, the refractive index of the quartz layer is lower than the refractive index of the third region, preferably, The refractive index of the 1, 2, and 3 regions doped with rare earth ions is the same and greater than the refractive index of the quartz material in the 4, 5, 6, and 7 regions. Therefore, the effective numerical aperture of the 1 region is: 0.3; the effective numerical aperture of the 2 region is: 0.3 ;3 area effective numerical aperture: 0.3. Therefore, areas 1, 2, and 3 all have an excellent function of limiting light transmission, which can basically realize the independent transmission of laser light in each area, and basically will not interfere with each other. Similar to the core of an optical fiber, that is, the optical fiber can be regarded as a ring-shaped multi-core structure fiber. As shown in Figures 2 and 4, the first part c of the bundling area, the second part b of the bundling area, and the third part a of the bundling area are respectively connected with the first area, the second area 2, the third area of the multi-core doped active fiber Area 1 corresponds to; that is, the first part c of the clustering area corresponds to the first area through the beamer cone area, the second part b of the beamer area passes through the beamer cone area and corresponds to the second area 2, and the third part a of the cluster area passes through The bundled cone region corresponds to the third region 3 .

And the d, e, and f of the bundled region correspond to regions 4, 5, and 7 of the multi-core doped active fiber, respectively. That is, the quartz low-refractive index glass tube between the first part of the clustering area and the second part of the clustering area corresponds to the quartz layer between the first area and the second area of the multi-core doped active fiber through the clustering taper area; clustering The silica low-refractive-index glass tube between the second part of the zone and the third part of the bundle zone passes through the bundle taper region and corresponds to the silica layer between the second zone and the third zone of the multi-core doped active fiber; the bundle zone The quartz low-refractive-index glass tube outside the third part corresponds to the quartz layer outside the third region of the multi-core doped active fiber through the condensing region.

Preferably, in the multi-wavelength amplified ring laser output by the multi-core doped active fiber, the first signal light L1, the first pump light P1 and the output laser part corresponding to the first region are the first output light part Q1; The output laser part corresponding to the second signal light L2 and the second pump light P2 and the second region is the second output light part Q2; the output laser part corresponding to the third signal light L3 and the third pump light P3 and the third region is The third output light part Q3; when the part of the bundle area exceeds 3 parts, the output laser part corresponding to the nth signal light Ln, the nth pump light Pn and the nth region is the nth output light part Qn (n>3 , is a positive integer).

For the amplification of the multi-core fiber laser, according to the above information, each region 1, 2, and 3 is doped with different rare earth ions, the third region 1 is doped with thulium ions, and the second region 2 is co-doped with erbium ions Ytterbium ions, the first region is doped with ytterbium ions. Depending on the design of the fiber structure, a numerical aperture exists in each region. At the same time, each kind of thulium, erbium-ytterbium, ytterbium laser that needs to be amplified and the corresponding pump laser are restricted to transmit in the 1, 2, and 3 regions, respectively. Therefore, the amplification of the above three lasers is spatially separated. Therefore, the output of each of the above lasers can be controlled by controlling the injection size of the signal light and the pump light in the 1, 2, and 3 regions. The amplifying structure is essentially a Mopa amplifying structure, so it has the characteristic that the amplified output laser depends on the beam quality of the signal laser. In this patent, single-mode laser of thulium, erbium and ytterbium is used as the signal light, so the output of high beam quality and high output power can be obtained.

In addition, the outer diameters of the signal fibers and the pump fibers in regions a, b, and c are the same as 125 μm. Therefore, under the condition that the total number of signal fibers and pump fibers in each area is kept unchanged, according to the application requirements, the ratio of the number of signal fibers and pump fibers can be adjusted, increasing the signal fiber and reducing the pump fiber, or reducing the signal Therefore, through this method, the injection ratio of signal light and pump light can be flexibly controlled, and finally the individual control output of each amplified laser can be realized.

Preferably, sometimes due to the slightly different taper conditions of each fiber in the bundle taper area, the energy transmission of each pump fiber and signal fiber is different, and thus the light field of the annular spot will appear slightly uneven. , in order to solve this problem, the inventor thought of making the energy and power of the pump laser corresponding to each pump fiber in each part of the cluster area independently adjustable. For example, the first part of the cluster area includes a plurality of pump fibers, each pump fiber The energy of the pump laser is independently adjustable, and a detection device (such as a CCD camera including an attenuator) is set at the output end of the multi-core doped rare-earth ion gain fiber. The light field uniformity of each pump fiber is independently adjusted to the pump laser power of each pump fiber. When the light field uniformity of the ring light spot obtained by the ring light spot detection device reaches a predetermined value, record the light field in each pump fiber at this time. The pump laser power value and/or the pump laser power ratio of each pump fiber, then use the pump laser power value in each pump fiber and/or the pump laser power ratio of each pump fiber to obtain uniform The first output laser section.

Preferably, it may also include that the second part of the bundle area includes a plurality of pump fibers, the energy of the pump laser in each pump fiber is independently adjustable, and a ring-shaped light spot is arranged at the output end of the multi-core doped rare-earth ion gain fiber The detection device (for example, a CCD camera including an attenuator), the pump laser power of each pump fiber is independently adjusted according to the light field uniformity of the annular spot detected by the annular spot detection device. When the annular spot detection device obtains When the uniformity of the light field of the annular spot reaches a predetermined value, record the pump laser power value in each pump fiber and/or the pump laser power ratio of each pump fiber at this time, and then use the pump laser power of each pump fiber. The pump laser power value in the fiber and/or the pump laser power ratio of each pump fiber to obtain a uniform second output laser portion.

Preferably, it may also include that the third part of the bundle area includes a plurality of pump fibers, the energy of the pump laser in each pump fiber is independently adjustable, and a ring-shaped light spot is arranged at the output end of the multi-core doped rare-earth ion gain fiber The detection device (for example, a CCD camera including an attenuator), the pump laser power of each pump fiber is independently adjusted according to the light field uniformity of the annular spot detected by the annular spot detection device. When the annular spot detection device obtains When the uniformity of the light field of the annular spot reaches a predetermined value, record the pump laser power value in each pump fiber and/or the pump laser power ratio of each pump fiber at this time, and then use the pump laser power of each pump fiber. The pump laser power value in the fiber and/or the pump laser power ratio of each pump fiber to obtain a uniform third output laser portion.

Preferably, it may also include that the nth part of the bundle area includes a plurality of pump fibers, the energy of the pump laser in each pump fiber is independently adjustable, and a ring-shaped light spot is arranged at the output end of the multi-core doped rare-earth ion gain fiber The detection device (for example, a CCD camera including an attenuator), the pump laser power of each pump fiber is independently adjusted according to the light field uniformity of the annular spot detected by the annular spot detection device. When the annular spot detection device obtains When the uniformity of the light field of the annular spot reaches a predetermined value, record the pump laser power value in each pump fiber and/or the pump laser power ratio of each pump fiber at this time, and then use the pump laser power of each pump fiber. The pump laser power value in the fiber and/or the pump laser power ratio of each pump fiber to obtain a uniform nth output laser portion (n>3, a positive integer).

In view of the structural design of the multi-core doped rare-earth ion gain fiber, the composite wavelength laser ring-spot laser output can be realized.

Through the design of the fiber structure, the number of core regions of the multi-core doped fiber can be increased to increase the doped rare earth ions, such as: neodymium, holmium, samarium, praseodymium, etc.; for the selection of the signal light wavelength in this patent, the The wavelength selection can be extended to the wavelengths covered by the emission spectrum of each doped rare earth ion.

The advantage of the present application is also to realize the structural design of the bundled fiber region combiner which is efficiently coupled with the multi-core doped fiber.

In addition to realizing the output of high-power composite wavelength lasers, the present application can also realize the output of composite wavelength ring spot lasers; at the same time, the single wavelength component lasers in the output composite wavelength lasers can be individually controlled. Preferably, the signal light module in the signal light module and the pump light module can independently control the light intensity and output or not of the signal laser light of each wavelength. The pump light module in the signal light and pump light module can independently control the light intensity and whether it is output or not.

Since the pump laser is multi-mode, there will be a mode mismatch when using a single-mode signal fiber, resulting in a low utilization efficiency of the pump light, wasting light energy and reducing efficiency. In order to solve this problem, the inventor replaced the signal fiber. It is a few-mode laser fiber to solve the problem of mode mismatch in the above pumping process. At the same time, both the core diameter of the few-mode signal fiber and the core diameter of the multi-mode pump fiber can be increased. Preferably, the signal fiber is selected as a few-mode fiber with a core diameter greater than 15 μm and a cladding diameter greater than 150 μm. The pump fiber is selected as a multimode fiber with a core diameter greater than 133 μm and a cladding diameter greater than 153 (or more preferably, the signal fiber is selected as a few-mode fiber with a core diameter greater than 18 μm and a cladding diameter greater than 180 μm, preferably, the pump The fiber is selected as a multimode fiber with a core diameter greater than 150 μm and a cladding diameter greater than 180); so that the multimode pump fiber can transmit more energy and reduce the energy density per unit section to reduce heat generation and nonlinear effects. At the same time, due to the limitation of the taper ratio, the core diameter and the cross-sectional area of each part of the multi-core doped rare-earth ion gain fiber can be correspondingly increased to output a higher-energy output laser and reduce the energy density per unit cross-section. nonlinear effects. For example, the embodiments described below may be included.

By designing the structure of the bundling area and the multi-core doped fiber, the pump fiber and the signal fiber in the bundling area are respectively replaced with fibers with the same cladding diameter, larger core diameter and higher numerical aperture. For example, the pump fiber can be replaced with a 200/220/0.22 multimode fiber, and the signal fiber can be replaced with a 20/200 few-mode laser fiber, which can reduce the demand for the brightness of the pump light by the amplifying structure, thereby reducing the manufacturing of the amplifying structure. cost.

The technical principle of the present invention has been described above with reference to the specific embodiments. These descriptions are only for explaining the principle of the present invention, and should not be construed as limiting the protection scope of the present invention in any way. Based on the explanations herein, those skilled in the art can think of other specific embodiments of the present invention without creative efforts, and these methods will all fall within the protection scope of the present invention.

Claims (10)

1. A multi-wavelength power-tunable fiber laser based on multi-core doped rare earth ions, including a signal light and a pump light module, a signal light and pump light output fiber bundle area, a bundle taper area, a multi-core doped fiber source fiber; The signal light and pump light module is used to output the signal laser to be amplified and the pump laser needed to realize the signal light amplification; The signal light and pump light output fiber bundle area includes the signal fiber and the pump fiber, which bundle the signal fiber and the pump fiber; the signal fiber is used to transmit the signal laser to be amplified, and the pump fiber is used to transmit the signal light to realize the signal light. The pump laser required for amplification; The bundle taper area is obtained by performing taper processing on the output fiber bundle area of the signal light and pump light; The beam-pulling region is connected with the multi-core doped active fiber. 2. A multi-wavelength power-tunable fiber laser based on multi-core doped rare-earth ions according to claim 1, the multi-core doped active fiber comprises at least two rare-earth ion regions, signal light and pump light output fiber bundles It includes the first part of the bundling area and the second part of the bundling area. The first part of the bundling area includes the signal fiber and the pumping fiber. The second part of the bundling area includes the signal fiber and the pumping fiber. The first part of the bundling area is basically a circular area. The two parts surround the first part of the bundling area. The second part of the bundling area is basically an annular area. The first part of the bundling area includes a first signal fiber and a first pump fiber. The first signal fiber is used to transmit the first signal laser L1, and the first pump fiber The pump fiber is used to transmit the first pump laser P1, and the second part of the cluster area includes a second signal fiber and a second pump fiber, the second signal fiber is used to transmit the second signal laser L2, and the second pump fiber is used to transmit The second pump laser P2; the first rare earth ion material absorbs the first pump laser P1 and makes the number of ions reversed, and emits the amplified first signal laser L1; the second rare earth ion material absorbs the second pump laser P2 and makes the number of ions Inverted, the amplified second signal laser L2 is emitted. 3. A kind of multi-wavelength power tunable fiber laser based on multi-core doped rare earth ions according to claim 2, further comprising the third part of the cluster region, the third part of the cluster region comprising a signal fiber and a pump fiber, the third part of the cluster region Basically a ring-shaped area, the third part of the bundling area surrounds the second part of the bundling area, the third part of the bundling area includes a third signal fiber and a third pump fiber, the third signal fiber is used to transmit the third signal laser L3, and the third pump The pump fiber is used to transmit the third pump laser light P3; the third rare earth ion material absorbs the third pump laser light P3 and inverts the number of ions, and outputs the amplified third signal laser light L3. 4. A multi-wavelength power-tunable fiber laser based on multi-core doped rare-earth ions according to claim 3, a quartz low-refractive index glass tube is arranged between the first part of the cluster region and the second part of the cluster region; A quartz low-refractive index glass tube is arranged between the part and the third part of the bundle area; the outermost part of the signal light and pump light output fiber bundle area includes a quartz low-refractive index glass tube, and the quartz low-refractive index glass tube has a lower refractive index than the pump. The core refractive index of the Pu fiber. 5. A multi-wavelength power tunable fiber laser based on multi-core doped rare earth ions according to claim 3, the multi-core doped active fiber comprises a first region, a second region and a third region, and the first region is doped with the first region. a rare earth ion for amplifying the first signal light; the second region surrounds the first region, the second region is a substantially annular region, doped with the second rare earth ion for amplifying the second signal light; the third region surrounds the second region The third region is a substantially annular region, and is doped with third rare earth ions for amplifying the third signal light. 6. A multi-wavelength power tunable fiber laser based on multi-core doped rare earth ions according to claim 4, the multi-core doped active fiber comprises a first region, a second region and a third region, and the first region is doped with the first region. a rare earth ion; the second region is a substantially annular region, doped with the second rare earth ion; the third region is a substantially annular region, doped with the third rare earth ion, and a quartz layer is arranged between the first region and the second region; A quartz layer is arranged between the second region and the third region; a quartz layer is arranged outside the third region, the refractive index of the quartz layer is lower than that of the first region, and the refractive index of the quartz layer is lower than the refractive index of the second region , the refractive index of the quartz layer is lower than that of the third region. 7. A kind of multi-wavelength power tunable fiber laser based on multi-core doped rare earth ions according to claim 5, the wavelength of the first signal laser L1 is less than the wavelength of the second signal laser L2 located in the second part of the cluster region; The wavelength of the second signal laser light L2 in the second part is smaller than the wavelength of the third signal laser light L3 in the third part of the bundle area. 8. A kind of multi-wavelength power-tunable fiber laser based on multi-core doped rare earth ions according to claim 3, the signal fiber in the first part of the bundle area is a passive matching single-mode fiber capable of transmitting the laser light that ytterbium ions can emit, The pump fiber in the first part of the cluster area is the coupling output fiber of the pump source that outputs the laser that can pump the ytterbium ion material; the signal fiber in the second part of the cluster area is the passive optical fiber that can transmit the laser light that the erbium ion can emit. Matching single-mode fiber, the pump fiber in the second part of the bundle area is the coupling output fiber of the pump source outputting the laser that can pump the erbium-ytterbium ion co-doped material; the signal fiber in the third part of the bundle area is capable of transmitting thulium ions The passive matching single-mode fiber that can emit laser light, and the pump fiber in the third part of the bundle area is the coupling output fiber of the pump source that outputs the laser that can pump the thulium ion material; the pump source is the laser diode pump source. 9. A multi-wavelength power-tunable fiber laser based on multi-core doped rare-earth ions according to claim 1, the taper length of the bundle taper region satisfies the insulating taper condition: the diffraction angle in the fiber ≥ the fiber taper angle, and the fiber After the taper is drawn, the end of the taper is cut, and after it is cut, it is spliced with the multi-core doped active fiber. 10. A kind of multi-wavelength power adjustable fiber laser based on multi-core doped rare earth ions according to claim 1, the signal fiber is a single-mode fiber, and the pump fiber is a multi-mode fiber; Or, the signal fiber is a few-mode laser fiber, The diameter of the pump fiber core is greater than 133 μm.

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