CN101383479A - Two-dimensional fiber laser array phase-locking and aperture filling device - Google Patents

Abstract

A two-dimensional fiber laser array phase locking and aperture filling device, composed of a total reflection mirror, a two-dimensional single-mode fiber array, a pump source, a phase compensation plate and a partial reflection/output mirror. The total reflection mirror and the partial reflection/output mirror and the two-dimensional single-mode fiber array and the phase compensation plate placed therein meet the Talbot self-imaging conditions to form a Lau effect resonant cavity. The invention has the advantages of simple structure, stable and reliable performance, high-power continuous output, etc., and is particularly suitable for laser radar, satellite laser communication, directed energy weapons and other fields, and has practical significance for the development of compact, lightweight and high-beam quality high-power laser systems.

Description

Two-dimensional fiber laser array phase-locking and aperture filling device

technical field

The invention relates to laser radar and satellite laser communication, especially a two-dimensional fiber laser array phase-locking and aperture filling device, which is used in laser radar and satellite laser communication transmission systems to generate high power and high optical quality near the diffraction limit Continuous laser output.

Background technique

Fiber laser is a new type of solid-state laser device recently developed in the world. It has the advantages of large heat dissipation area, good beam quality and small size. It is used in high-precision laser processing, optical communication, laser radar, space technology, high-energy weapons and laser medicine. applied in other fields. With the development of laser application technology, high-power, high-quality and high-brightness laser beams are required in fields such as laser radar, and they are developing in the direction of miniaturization, full solid-state, and high power. Generally speaking, the continuous output power obtained from a single fiber laser is limited, so a phase-locked array structure is adopted to achieve phase-locking of multiple laser beams.

The requirements for phase-locking of fiber laser arrays are that the resonator of the fiber array laser is easy to vibrate, has stable mode output and good beam quality, and can produce a single main lobe intensity output in the far field. The ultimate goal is to obtain high output power while ensuring Good beam quality. Among various fiber laser array phase-locking methods, Talbot external cavity phase-locking technology is a very effective technology. As we all know, coherent light with a certain periodicity in intensity distribution will appear its own image after a certain distance, and this distance is called the Talbot distance. For a periodically arranged laser array, a plane mirror with a certain reflectivity is placed at the Talbot distance, and what is coupled into the laser after reflection is its own Talbot image, thus forming a stable coherent light field output. Prior Art 1 (see M.Wrage, P.Glas, et al., Phase locking in a multicore fiber laser by means of a Talbot resonator, Opt.Lett., 25(19), 436-1438, 2000.) , the multi-core fiber laser is mode-selected with Talbot external cavity, and the phase-locked output is realized. However, this method only phase-locks the array laser, but a considerable part of the energy is distributed in the sidelobe of the array far field.

In order to concentrate the side lobe energy into the central main lobe, the aperture of the phase-locked laser array must be filled to obtain a single far-field zero-order main lobe, and a constant-amplitude in-phase wavefront must be generated in the near-field. A phase compensation plate is placed between the end face of the laser array and the output mirror, and the phase-locking and aperture filling of the laser array are carried out by using Talbot self-imaging and phase compensation effects to obtain a single main lobe output in the far field. In fact, a self-imaging cavity with a phase compensation plate resembles a Lau effect device. In prior art 2 (see Liren Liu, Lau cavity and phase locking of laser arrays, Opt. Lett., 14(23), 1312-1314, 1989.), a Lau effect resonant cavity with a phase compensation plate was designed to realize The phase-locking and coherent output of the semiconductor laser array are covered, but the phase-locking and aperture filling of the fiber laser array are not involved, and it is a one-dimensional laser array phase-locking.

Contents of the invention

The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art, and provide a two-dimensional area array fiber laser array phase-locking and aperture filling device to produce continuous laser beam output with high power and high optical quality.

Technical solution of the present invention is as follows:

A two-dimensional fiber laser array phase-locking and aperture filling device, including a total reflection mirror, a single-mode fiber array, a pump source, a phase compensation plate and a partial reflection/output mirror, is characterized by:

The total reflection mirror, the single-mode fiber array, the phase compensation plate and the partial reflection/output mirror are arranged in sequence on the same optical axis;

The single-mode fiber array is formed by arranging a plurality of single-mode fibers, and its cross section has a symmetrical two-dimensional lattice structure. One end of the single-mode fiber array is close to the total reflection mirror, The other end is the output end, the diameter of each single-mode fiber core is d, the periods of the two orthogonal directions are T _1x and T _1y respectively, and the duty cycles of the two orthogonal directions of the fiber array are defined as d/T _1x and d/T _1y ;

The pumping source is composed of a plurality of semiconductor laser diodes;

Each single-mode fiber in the single-mode fiber array is connected to a semiconductor laser diode in the pump source to form a laser pumping relationship;

The distance _Z1 from the output end face of the single-mode fiber array to the phase compensation plate satisfies the Talbot (Talbot) effect self-imaging condition:

${\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}{{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}\frac{{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}{{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}\frac{{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; <figure-callout\; id="2"\; label="y"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">y</figure-callout></span>}}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}}$

Among them: α _1x , β _1x and α _1y , β _1y are coprime positive integers, λ is the laser wavelength, and the reciprocal T _1x /d of the duty cycle in two orthogonal directions T 1x /d=β _1x , T _1y / d=β _1y is an integer, then a first-class amplitude pure phase distribution light field will be produced in Z ₁ ;

The transmittance function t(x, y) of the phase compensation plate is the complex conjugate function of the equal-amplitude pure phase distribution light field at the _z1 place;

The distance between the phase compensation plate and the partial reflection/output mirror satisfies the Talbot self-imaging and Lau effect conditions: $\frac{z_1{z}_2}{z_1+{\mathrm{<figure-callout\; id="2"\; label="z"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">z</figure-callout>}}_2}=\frac{{\mathrm{\&alpha;}}_{2x}}{{\mathrm{\&beta;}}_{2x}}\frac{T_{2x}^2}{\mathrm{\&lambda;}}=\frac{{\mathrm{\&alpha;}}_{2\mathrm{the\; y}}}{{\mathrm{\&beta;}}_{2\mathrm{the\; <figure-callout\; id="2"\; label="y\; T"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">y</figure-callout>}}}\frac{T_{}^{}}{}\frac{{}_{2\mathrm{the\; <figure-callout\; id="2"\; label="y"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">y</figure-callout>}}^2}{\mathrm{\&lambda;}}$

z ₂ >>z ₁

In the formula: α _2x , β _2x and α _2y , β _2y are all relatively prime positive integers.

A two-dimensional fiber laser array phase-locking and aperture filling device, including a single-mode fiber array, a pump source, a phase compensation plate and a partial reflection/output mirror, is characterized in that:

The single-mode fiber array, the phase compensation plate and the partial reflection/output mirror are sequentially arranged on the same optical axis;

The single-mode optical fiber array is formed by arranging a plurality of single-mode optical fibers, and its cross section has a symmetrical two-dimensional lattice structure. One end of the single-mode optical fiber array is coated with a total reflection film, and the other end is an output end, the diameter of each single-mode fiber core is d, the periods of the two orthogonal directions are T _1x and T _1y respectively, and the duty ratios of the two orthogonal directions of the fiber array are defined as d/T _1x and d/T _1y respectively ;

The pumping source is composed of a plurality of semiconductor laser diodes;

Each single-mode fiber in the single-mode fiber array is connected to a semiconductor laser diode in the pump source to form a laser pumping relationship;

The distance _Z1 from the output end face of the single-mode fiber array to the phase compensation plate satisfies the Talbot (Talbot) effect self-imaging condition:

${\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}{{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}\frac{{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}{{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}\frac{{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; <figure-callout\; id="2"\; label="y"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">y</figure-callout></span>}}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}}$

Among them: α _1x , β _1x and α _1y , β _1y are coprime positive integers, λ is the laser wavelength, and the reciprocal T _1x /d of the duty cycle in two orthogonal directions T 1x /d=β _1x , T _1y / d=β _1y is an integer, then a first-class amplitude pure phase distribution light field will be produced in Z ₁ ;

The transmittance function t(x, y) of the phase compensation plate is the complex conjugate function of the equal-amplitude pure phase distribution light field at the _z1 place;

The distance between the phase compensation plate and the partial reflection/output mirror satisfies the Talbot self-imaging and Lau effect conditions: $\frac{z_1{z}_2}{z_1+{\mathrm{<figure-callout\; id="2"\; label="z"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">z</figure-callout>}}_2}=\frac{{\mathrm{\&alpha;}}_{2x}}{{\mathrm{\&beta;}}_{2x}}\frac{T_{2x}^2}{\mathrm{\&lambda;}}=\frac{{\mathrm{\&alpha;}}_{2\mathrm{the\; y}}}{{\mathrm{\&beta;}}_{2\mathrm{the\; <figure-callout\; id="2"\; label="y\; T"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">y</figure-callout>}}}\frac{T_{}^{}}{}\frac{{}_{2\mathrm{the\; <figure-callout\; id="2"\; label="y"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">y</figure-callout>}}^2}{\mathrm{\&lambda;}}$

z ₂ >>z ₁

In the formula: α _2x , β _2x and α _2y , β _2y are all relatively prime positive integers.

The output end face of the single-mode fiber array is coated with an anti-reflection film.

The cross-section of the single-mode fiber array is regular triangle, square, rectangle, circle or hexagon.

Technical effect of the present invention is as follows:

Since the total reflection mirror and partial reflection/output mirror of the present invention and the optical fiber array placed therein form a Lau effect resonant cavity, after the optical fiber array of incoherent spontaneous emission is transmitted in the resonant cavity for a week, a correct self-imaging periodic array is produced, and the original radiation The light field and the light field oscillating back in the resonant cavity are superimposed to produce a laser output in a stable resonant mode. Compared with other external cavity beam technology, the Lau effect external cavity technology has obvious advantages: it can realize the reproduction of the field of the array light-emitting unit, and through the selection of the mode of the external cavity, the far-field single lobe intensity output can be realized, and the external cavity adopts The output is coupled by a plane mirror, and the structure is simple and stable.

The distance from the output end face of the optical fiber array to the phase compensation plate satisfies the fractional Talbot (Talbot) effect self-imaging condition, and the wavefront of the pure phase distribution is generated at this distance, and the phase distribution of the phase compensation plate is the optical field The complex conjugate of the phase distribution, so that the light field output through the phase compensation plate is a constant-amplitude continuous plane wave;

The distance from the laser beam array output by the single-mode fiber array to the phase compensation plate satisfies the fractional Talbot effect self-imaging condition, and the array light field with amplitude distribution will be converted into a light field distribution with equal amplitude periodic phase change. The correction of the conjugate phase compensation plate makes it a uniform phase light field distribution. The light field returned by the partially reflected output mirror is freely transmitted to the phase compensation plate. Also due to the fractional Talbot self-imaging effect, the periodic phase change field distribution diffracted to the end face of the fiber array will produce a correct array self-image, thus forming a Lau resonant cavity , the necessary conditions for the continuous oscillation of the resonator are met, and finally the output mirror outputs the laser in a stable mode to realize the phase-locking and aperture filling of the fiber laser array.

The technology of the invention is simple, the principle is reliable, and it is also suitable for the phase-locking of a large number of optical fiber arrays and other types of solid-state laser arrays. It is especially suitable for the fields of laser radar, satellite laser communication and directed energy weapons, and has practical significance for the development of compact, lightweight and high-power laser systems with high beam quality.

Description of drawings

Fig. 1 is a schematic structural diagram of Embodiment 1 of a fiber laser array phase-locking and aperture filling device of the present invention.

Fig. 2 is a schematic diagram of the forward transmission simulation of optical field equivalent transmission in the coherent radiation state of the present invention.

Fig. 3 is a schematic diagram of simulation of optical field equivalent transmission and reverse transmission in the coherent radiation state of the present invention.

Fig. 4 is a schematic diagram of forward transmission simulation of optical field equivalent transmission in the initial incoherent radiation state of the present invention.

Fig. 5 is a schematic diagram of simulation of optical field equivalent transmission and reverse transmission in the initial incoherent radiation state of the present invention.

In the figure: 1—total reflection mirror, 2—single-mode fiber array, 3—pump source, 4—phase compensation plate, 5—partial reflection/output mirror. z ₁ is the distance from the single-mode fiber array 2 to the phase compensation plate 4 , and z ₂ is the distance from the phase compensation plate 4 to the partial reflection/output mirror 5 .

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and embodiments, but the protection scope of the present invention should not be limited thereby.

Please refer to FIG. 1 first. FIG. 1 is a schematic structural diagram of Embodiment 1 of the fiber laser array phase-locking and aperture filling device of the present invention. As can be seen from the figure, the two-dimensional fiber laser array phase-locking and aperture filling device of the present invention includes a total reflection mirror 1, a single-mode fiber array 2, a pump source 3, a phase compensation plate 4 and a partial reflection/output mirror 5, and its characteristics are:

The total reflection mirror 1, the single-mode fiber array 2, the phase compensation plate 4 and the partial reflection/output mirror 5 are arranged in sequence with the optical axis;

The single-mode fiber array 2 is formed by a plurality of single-mode fibers closely arranged, and its cross-section has a symmetrical two-dimensional lattice structure. One end of the single-mode fiber array 2 is close to the full Reflector 1, the other output end face is coated with anti-reflection coating, the diameter of each single-mode fiber core is d, and the periods of the two orthogonal directions are T _1x and T _1y respectively, defining the duty cycle of the two orthogonal directions of the fiber array are d/T _1x and d/T _1y respectively;

The pumping source 3 is composed of a plurality of semiconductor laser diodes;

Each single-mode fiber in the single-mode fiber array 2 is connected to a semiconductor laser diode in the pump source 3 to form a laser pumping relationship;

The distance _Z1 from the output end face of the single-mode fiber array 2 to the phase compensation plate 4 satisfies the Talbot (Talbot) effect self-imaging condition:

${\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}{{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}\frac{{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}{{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}\frac{{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; <figure-callout\; id="2"\; label="y"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">y</figure-callout></span>}}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}}$

Among them: α _1x , β _1x and α _1y , β _1y are coprime positive integers, λ is the laser wavelength, and the reciprocal T _1x /d of the duty cycle in two orthogonal directions T 1x /d=β _1x , T _1y / d=β _1y is an integer, then a first-class amplitude pure phase distribution light field will be produced in Z ₁ ;

The transmittance function t(x, y) of the phase compensation plate 4 is the complex conjugate function of the equal-amplitude pure phase distribution light field at z ₁ , and the light field output from the phase compensation plate 4 is duty cycle Equal-amplitude continuous plane waves with a ratio of 1:1;

The distance between the phase compensation plate 4 and the partial reflection/output mirror 5 satisfies the Talbot self-imaging and Lau effect conditions: $\frac{z_1{z}_2}{z_1+{\mathrm{<figure-callout\; id="2"\; label="z"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">z</figure-callout>}}_2}=\frac{{\mathrm{\&alpha;}}_{2x}}{{\mathrm{\&beta;}}_{2x}}\frac{T_{2x}^2}{\mathrm{\&lambda;}}=\frac{{\mathrm{\&alpha;}}_{2\mathrm{the\; y}}}{{\mathrm{\&beta;}}_{2\mathrm{the\; <figure-callout\; id="2"\; label="y\; T"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">y</figure-callout>}}}\frac{T_{}^{}}{}\frac{{}_{2\mathrm{the\; <figure-callout\; id="2"\; label="y"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">y</figure-callout>}}^2}{\mathrm{\&lambda;}}$

z ₂ >>z ₁

In the formula: α _2x , β _2x and α _2y , β _2y are all relatively prime positive integers.

The diameter of each fiber core in the single-mode fiber array 2 is d, the periods of the two orthogonal directions are T _1x and T _1y respectively, and the duty cycles of the two orthogonal directions of the fiber array are defined as d/T _1x and d/T _1y , so the single-mode fiber array 2 can be regarded as an amplitude-type periodic structure with a specific duty ratio.

The direction in which the light field output from the output end face of the single-mode fiber array 2 is transmitted to the phase compensation plate 4 and then transmitted to the partial reflection/output mirror 5 is defined as the forward transmission direction, and the light reflected from the partial reflection/output mirror 5 The direction of transmission to the phase compensation plate 4 and further transmission to the end face of the single-mode fiber array 2 is defined as the reverse transmission direction.

The distance from the single-mode fiber array 2 to the phase compensation plate 4 $z_1=\frac{{\mathrm{\&alpha;}}_{1x}}{{\mathrm{\&beta;}}_{1x}}\frac{{T_{1x}}^2}{\mathrm{\&lambda;}}=\frac{{\mathrm{\&alpha;}}_{1\mathrm{the\; y}}}{{\mathrm{\&beta;}}_{1\mathrm{the\; y}}}\frac{{T_{1\mathrm{the\; <figure-callout\; id="2"\; label="y"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">y</figure-callout>}}}^2}{\mathrm{\&lambda;}}$

Among them: α _1x , β _1x and α _1y , β _1y are coprime positive integers, which satisfy the fractional Talbot effect self-imaging condition, and the reciprocal T _1x /d of the duty cycle in two orthogonal directions =β _1x , T _1y /d=β _1y is an integer, at this time, the array light field of amplitude distribution is converted into the light field of pure phase distribution;

The single-mode fiber array 2, the phase compensation plate 4 and the output mirror 5 form a Lau effect resonant cavity, and the light field output from the single-mode fiber array 2 can go back and forth in the resonant cavity for a week on the end face of the single-mode fiber array 2. Generate correct array self-imaging and form a stable mode of light field output.

Taking the two-dimensional optical fiber array arranged in an orthogonal period as an example, the specific design principle of the phase compensation plate 4 is described:

Assuming that the optical field radiated by the single-mode fiber array 2 is spatially completely coherent light, its complex amplitude is u ₀ (x, y, 0), and T _1x and T _1y are respectively the two orthogonal directions of x and y of the single-mode fiber array cycle. Figure 2 and Figure 3 show the schematic diagrams of the equivalent transmission simulation of the spatially fully coherent radiation array light field.

According to the Fresnel diffraction formula, the diffraction field of the single-mode fiber array 2 at the z distance is approximated by:

${\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; z</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; exp</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; ikz</span>}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; i\&lambda;z</span>}}{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; *</span><span\; class="notranslate">\; *</span>\mathrm{<span\; class="notranslate">\; h</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; z</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

In the formula, k=2π/λ, λ is the laser wavelength, h(x, y, z)=exp[iπ(x ² +y ² )/λz], and ' ^** ' means two-dimensional convolution.

After Fourier series expansion of the periodic function u ₀ (ξ, η, 0), the diffracted light field at a distance z can be written as:

u ₁ (x, y, z) = u _p (x, y, 0)**Δ(x, y, z) (2)

In the formula, $\mathrm{\&Delta;}(x,\mathrm{the\; y},z)=\frac{1}{T_{1x}{T}_{1\mathrm{the\; y}}}\left[\underset{\mathrm{no}}{\mathrm{\&Sigma;}}\underset{m}{\mathrm{\&Sigma;}}\exp [-\mathrm{i\&pi;\&lambda;z}(\frac{m^2}{T_{1x}^2}+\frac{{\mathrm{no}}^2}{T_{1\mathrm{the\; y}}^2})]\exp \left[2\mathrm{i\&pi;}(\frac{m}{T_{1x}}x+\frac{\mathrm{no}}{T_{1\mathrm{the\; y}}}\mathrm{the\; y})\right]\right],u_p(\mathrm{\&xi;},\mathrm{\&eta;},0)$

is a periodic function expression of the function u ₀ (ξ, η, 0), which can be a circular function or a rectangular function.

In the design of the present invention, the phase compensation plate 4 is placed on the fractional Talbot distance:

$z_1=\frac{{\mathrm{\&alpha;}}_{1x}}{{\mathrm{\&beta;}}_{1x}}\&Center\; Dot;\frac{T_{1x}^2}{d}=\frac{{\mathrm{\&alpha;}}_{1\mathrm{the\; y}}}{{\mathrm{\&beta;}}_{1\mathrm{the\; y}}}\&Center\; Dot;\frac{T_{1\mathrm{the\; y}}^2}{d}$ In the plane, when the aperture filling condition ${\mathrm{\&beta;}}_{1x}=\frac{T_{1x}}{d},$ ${\mathrm{\&beta;}}_{1\mathrm{the\; y}}=\frac{T_{1\mathrm{the\; y}}}{d}$ When satisfied, the diffraction field u ₁ (x, y, z ₁ ) is a pure phase distribution with equal amplitude, that is, |u ₁ (x, y, z ₁ )|=K, where K is a constant.

The transmittance function t(x, y) of the phase compensation plate 4 is the complex conjugate function of the equal-amplitude pure phase distribution light field at z ₁ , and the complex number of the diffraction field u ₁ (x, y, z ₁ ) Conjugate function, that is

$\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}^{<span\; class="notranslate">\; *</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; K</span>}$

$=\left({\mathrm{\&beta;}}_{1x}{\mathrm{\&beta;}}_{1\mathrm{the\; y}}\right)u_p(x,\mathrm{the\; y})**\mathrm{\&Delta;}(x,\mathrm{the\; y},z_1)$ (3)

Among them, when α _1x β _1x and α _1y β _1y are even numbers,

$\mathrm{<span\; class="notranslate">\; \&Delta;</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\underset{\mathrm{<span\; class="notranslate">\; k</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}\underset{\mathrm{<span\; class="notranslate">\; l</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; kl</span>}}\mathrm{<span\; class="notranslate">\; \&delta;</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; k</span>}{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}{{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; \&delta;</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; l</span>}{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}{{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; )</span>$

$R_{\mathrm{kl}}=\frac{1}{{\mathrm{\&beta;}}_{1x}{\mathrm{\&beta;}}_{1\mathrm{the\; y}}}\underset{m\&prime;}{\mathrm{\&Sigma;}}\underset{\mathrm{no}\&prime;}{\mathrm{\&Sigma;}}\exp \left[\mathrm{i\&pi;}(\frac{{\mathrm{\&alpha;}}_{1x}}{{\mathrm{\&beta;}}_{1x}}{m}^{\&prime;2}+\frac{{\mathrm{\&alpha;}}_{1\mathrm{the\; y}}}{{\mathrm{\&beta;}}_{1\mathrm{the\; y}}}{\mathrm{no}}^{\&prime;2})\right]\exp [-2\mathrm{i\&pi;}(\frac{\mathrm{km}\&prime;}{{\mathrm{\&beta;}}_{1x}}+\frac{\ln \&prime;}{{\mathrm{\&beta;}}_{1\mathrm{the\; y}}})],$ m=kβ _1x +m',

n=lβ _1x +n' where m'=0, 1, ..., (β _1x -1), n' = 0, 1, ..., (β _1y -1) and k, l = 0, ±1, ± 2,…. When α _1x β _1x and α _1y β _1y are odd numbers,

$\mathrm{<span\; class="notranslate">\; \&Delta;</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\underset{\mathrm{<span\; class="notranslate">\; k</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}\underset{\mathrm{<span\; class="notranslate">\; l</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; kl</span>}}\mathrm{<span\; class="notranslate">\; \&delta;</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; k</span>}{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}{{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}<span\; class="notranslate">\; -</span>\frac{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}{\mathrm{<span\; class="notranslate">\; 2</span>}{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; \&delta;</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; l</span>}{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}{{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}<span\; class="notranslate">\; -</span>\frac{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; <figure-callout\; id="2"\; label="y"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">y</figure-callout></span>}}}{\mathrm{<span\; class="notranslate">\; 2</span>}{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 5</span>}<span\; class="notranslate">\; )</span>$

${\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; kl</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}\underset{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; \&prime;</span>}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}\underset{\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; \&prime;</span>}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}\mathrm{<span\; class="notranslate">\; exp</span>}<span\; class="notranslate">\; [</span>\mathrm{<span\; class="notranslate">\; i\&pi;</span>}<span\; class="notranslate">\; (</span>\frac{{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}{{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}{\mathrm{<span\; class="notranslate">\; m</span>}}^{<span\; class="notranslate">\; \&prime;</span>\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; +</span>\frac{{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}{{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}{\mathrm{<span\; class="notranslate">\; no</span>}}^{<span\; class="notranslate">\; \&prime;</span>\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ]</span>\mathrm{<span\; class="notranslate">\; exp</span>}<span\; class="notranslate">\; [</span><span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; i\&pi;</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; km</span>}<span\; class="notranslate">\; \&prime;</span>}{{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; lm</span>}<span\; class="notranslate">\; \&prime;</span>}{{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ]</span><span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; \&prime;</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0,1</span>}<span\; class="notranslate">\; ,</span><span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; \&CenterDot;</span><span\; class="notranslate">\; ,</span>$

(2β _1x −1), n′=0, 1, . . . , (2β _1y −1) and k, l=0, ±1, ±2, . . .

Therefore, in the forward transmission direction, the light field output by the single-mode fiber array 2 whose period is T _1x and T _1y is incident on the phase compensation plate 4, and their distance z ₁ satisfies the Talbot self-imaging condition, and the single-mode The output light field of the fiber array 2 is regarded as an amplitude grating, and the periodic array of amplitude distribution will be converted into a field distribution of equal-amplitude periodic phase change, and the correction of the conjugate phase compensation plate 4 makes it a field distribution of uniform phase, that is, a plane wave. Then it propagates to the partial reflection/output mirror 5 to generate the far-field intensity output of a single main lobe.

Similarly, in the reverse transmission direction, as shown in Figure 3, the plane wave reflected by the partial reflection/output mirror 5 with reflectivity r is vertically irradiated on the phase compensation plate 4, due to the Talbot self-imaging effect, at a distance from the phase plate 4 At the end face of the single-mode fiber array 2 at a distance z ₁ , the light field coupled back into the single-mode fiber array 2 and considering (5) can be expressed as:

${\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}^{<span\; class="notranslate">\; \&prime;</span>}<span\; class="notranslate">\; [</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ]</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; kexp</span>}<span\; class="notranslate">\; [</span>\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; ik</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ]</span>\frac{\mathrm{<span\; class="notranslate">\; exp</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; ik</span>}{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; i\&lambda;</span>}{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; *</span><span\; class="notranslate">\; *</span>\mathrm{<span\; class="notranslate">\; exp</span>}<span\; class="notranslate">\; [</span>\mathrm{<span\; class="notranslate">\; ik</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; x</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; the\; y</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; 2</span>}{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; ]</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 6</span>}<span\; class="notranslate">\; )</span>$

$=\mathrm{rexp}\left[2\mathrm{ik}(z_1+z_2)\right]u_1(x,\mathrm{the\; y},0)$

Therefore, the light field reflected back from the partial reflection/output mirror 5 is transmitted to the phase compensation plate 4. Also due to the self-imaging effect, the periodic phase change field distribution diffracts to the fiber array surface to produce a correct array self-image, and the light field The only difference is a proportionality constant and a propagation factor. Having this kind of resonant cavity that can make the periodic distribution light field produce correct self-imaging effect can make the single-mode fiber laser array radiate the light field. After multiple effective oscillations in the cavity, the field distribution on the output surface is basically unchanged, and a stable mode is obtained. The output is a spatially fully coherent field.

It should be noted that the field strength and phase distribution at the fractional Talbot distance of the non-orthogonal periodic array can be rotated or tilted by the coordinates, and the phase distribution of the phase compensation plate can be obtained by a similar calculation method.

When the single-mode fiber array 2 is in the initial excitation state, the radiated light field is incoherent, and the forward transmission process is shown in Figure 4, which can be regarded as a plurality of T _1x and T _1y cycles in the x and y directions. Superposition of point source spherical waves,

${\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\underset{\mathrm{<span\; class="notranslate">\; m</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}\underset{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}\mathrm{<span\; class="notranslate">\; rect</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; m</span>}{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; rect</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; no</span>}{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; exp</span>}<span\; class="notranslate">\; \{</span>\frac{\mathrm{<span\; class="notranslate">\; i\&pi;</span>}}{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; [</span>{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; m</span>}{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; +</span>{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; no</span>}{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; ]</span><span\; class="notranslate">\; \}</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 7</span>}<span\; class="notranslate">\; )</span>$

After passing through the phase compensation plate 4 with a period of T _2x and T _2y , the light field distribution on the partial reflection/output mirror 5 at the transmission distance z ₂ is:

${\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; z</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; exp</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; ik</span>}{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; i\&lambda;</span>}{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; [</span>{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ]</span><span\; class="notranslate">\; *</span><span\; class="notranslate">\; *</span>\mathrm{<span\; class="notranslate">\; h</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; )</span>$

$=\frac{\exp \left(\mathrm{ik}{z}_2\right)}{\sqrt{\mathrm{i\&lambda;}{z}_2}}\sqrt{\frac{z_1}{z_1+{\mathrm{<figure-callout\; id="2"\; label="z"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">z</figure-callout>}}_2}}\exp \left[\frac{\mathrm{i\&pi;}}{\mathrm{\&lambda;}{z}_2}(x^2+{\mathrm{the\; y}}^2)\right]u_x\left(x\right)u_{\mathrm{the\; y}}\left(\mathrm{the\; y}\right)---\left(8\right)$

in,

${\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; x</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; exp</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; i\&pi;</span>}\frac{{\mathrm{<span\; class="notranslate">\; m</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; )</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}\underset{\mathrm{<span\; class="notranslate">\; m</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}\underset{\mathrm{<span\; class="notranslate">\; no</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}\mathrm{<span\; class="notranslate">\; G</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; m</span>}}{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; h</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; no</span>}}{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; exp</span>}<span\; class="notranslate">\; [</span><span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; i\&pi;</span>}\frac{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}{{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}{<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; x</span>}}{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="2"\; label="z"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">z</figure-callout></span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; m</span>}{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; m</span>}}{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; no</span>}}{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; ]</span>$

${\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; the\; y</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; exp</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; i\&pi;</span>}\frac{{\mathrm{<span\; class="notranslate">\; m</span>}}^{<span\; class="notranslate">\; \&prime;</span>\mathrm{<span\; class="notranslate">\; 2</span>}}{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; <figure-callout\; id="2"\; label="y"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">y</figure-callout></span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; )</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; <figure-callout\; id="2"\; label="y\; T"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">y</figure-callout></span><figure-callout\; id="2"\; label="y\; T"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">\; </figure-callout>}}{\mathrm{<span\; class="notranslate">\; </span>}}_{}{\mathrm{<span\; class="notranslate">T</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}\underset{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; \&prime;</span>}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}\underset{\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; \&prime;</span>}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}\mathrm{<span\; class="notranslate">\; G</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; \&prime;</span>}{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; h</span>}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; \&prime;</span>}{{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="2"\; label="T"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">T</figure-callout></span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; exp</span>}<span\; class="notranslate">\; [</span><span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; i\&pi;</span>}\frac{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}{{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}{<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; the\; y</span>}}{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="2"\; label="z"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">z</figure-callout></span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; \&prime;</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}{\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; m</span>}<span\; class="notranslate">\; \&prime;</span>}{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; \&prime;</span>}{{\mathrm{<span\; class="notranslate">\; <figure-callout\; id="2"\; label="T"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">T</figure-callout></span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; ]</span>$

Where G(m/T _1x , n/T _1y ) is the Fourier coefficient of the periodic function u ₀ (x, y), H(m'/T _2x , n'/T _2y ) is the periodic function t(x, y) The Fourier coefficients of . It can be seen from (8) that when the condition is satisfied $\frac{z_1{z}_2}{z_1+{\mathrm{<figure-callout\; id="2"\; label="z"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">z</figure-callout>}}_2}=\frac{{\mathrm{\&alpha;}}_{2x}}{{\mathrm{\&beta;}}_{2x}}\frac{T_{2x}^2}{\mathrm{\&lambda;}}=\frac{{\mathrm{\&alpha;}}_{2\mathrm{the\; y}}}{{\mathrm{\&beta;}}_{2\mathrm{the\; <figure-callout\; id="2"\; label="y\; T"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">y</figure-callout>}}}\frac{T_{}^{}}{}\frac{{}_{2\mathrm{the\; <figure-callout\; id="2"\; label="y"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">y</figure-callout>}}^2}{\mathrm{\&lambda;}}$ (wherein α _2x , β _2x , and α _2y , β _2y are all coprime positive integers), a light field with periodic Lau fringe distribution is also generated at the distance z ₂ .

Similarly, in the reverse direction of transmission, as shown in Figure 5, the light field u ₁ (x, y, z) at the distance z ₂ is also regarded as multiple point source spherical wave light sources, and the light field irradiates the phase compensation plate 4 also satisfies the Talbot self-imaging condition, similar to formula (8), at the end face of the single-mode fiber array 2, a correct self-image with the same period or an integer multiple of the period of the original single-mode fiber array 2 is generated. In this way, the original radiation light field of the single-mode fiber array 2 and the periodic light field returned by oscillation are coupled in the Lau resonator, and a stable mode laser field is formed after multiple oscillation transmissions to realize phase-locking and aperture filling of the single-mode fiber array 2 .

The present invention will be further described below by a specific embodiment:

10×10 semiconductor diode lasers are used as the pumping source 3, and the pumping wavelength is 975nm; the single-mode 2 adopts 10×10 Yb/Er-doped double-clad optical fibers, the length of which is 10m, and the output wavelength is 1.5μm. In two vertical directions, a 10×10 square array is arranged at a periodic interval T _1x and T _1y , and T _1x = T _1y = 200 μm, and the core diameter is d _x = d _y = 20 μm, so the single-mode fiber array 2 In x, the duty ratio of y direction d _x /T _1x =d _y /T _1y =0.1; the two end faces of these fiber arrays are ground so that they are all in the same plane, and the output end face of the single-mode fiber array 2 is for The working wavelength of 1.5μm is coated with an anti-reflection coating to allow as much return light as possible to be coupled into the fiber array.

The total reflection mirror 1, the partial reflection/output mirror 5 and the phase compensation plate 4 are assumed to be infinite relative to the single-mode fiber array 2, and the Talbot self-imaging distance $z_1=\frac{{\mathrm{\&alpha;}}_{1x}}{{\mathrm{\&beta;}}_{1x}}\frac{T_{1x}^2}{\mathrm{\&lambda;}}=\frac{{\mathrm{\&alpha;}}_{1\mathrm{the\; y}}}{{\mathrm{\&beta;}}_{1\mathrm{the\; y}}}\frac{T_{1\mathrm{the\; <figure-callout\; id="2"\; label="y"\; filenames="A200810200759E00141.png,A200810200759E00142.png"\; state="\{\{state\}\}">y</figure-callout>}}^2}{\mathrm{\&lambda;}},$ make $\frac{{\mathrm{\&alpha;}}_{1x}}{{\mathrm{\&beta;}}_{1x}}=\frac{{\mathrm{\&alpha;}}_{1\mathrm{the\; y}}}{{\mathrm{\&beta;}}_{1\mathrm{the\; y}}}=\frac{1}{10},$ β _1x = 10, β _1y = 10, a period-varying wavefront of pure phase distribution is produced at a distance of z ₁ = 2.67mm, and the phase compensation plate 4 should be designed as the complex conjugate of these phases, as shown in Table 1, where All phase values range from 0 to 2π, and phases that are integer multiples of 2π are omitted.

It should be noted that although the number of phases in Table 1 is 10×10=100. Because there is a symmetrical phase distribution in each cycle in the x and y directions, there are at most 6×6=36 phase values, which greatly simplifies the difficulty of making the phase plate.

According to the above calculation, the phase compensation plate 4 is placed at a distance of 2.67mm from the end face of the single-mode fiber array 2, and the period _T2 of the phase grating is _T1 /10=20μm, and the period _T2 is equal to the fiber core diameter d, so it occupies The space ratios are d/T _2x =1:1 and d/T _2y =1:1, thus generating wavefronts with equal amplitude and equal phase distribution at the z ₁ distance.

The distance z ₂ between the phase compensation plate 4 and the partial reflection/output mirror 5 satisfies the Lau effect condition, and takes $\frac{{\mathrm{\&alpha;}}_{2x}}{{\mathrm{\&beta;}}_{2x}}=\frac{{\mathrm{\&alpha;}}_{2\mathrm{the\; y}}}{{\mathrm{\&beta;}}_{2\mathrm{the\; y}}}=5,$ z ₂ =19.97mm. At this time, after the light field passing through the phase compensation plate 4 travels for a distance of z ₁ , a correct self-image with the same period or an integer multiple of the period of the original single-mode fiber array will be produced. In this way, the original radiation light field of the fiber array and the light field returned by oscillation are superimposed to form a coherently oscillating Lau resonator, which forms a stable mode laser field after multiple oscillation transmissions, and realizes phase-locking and aperture filling of the single-mode fiber array 2. That is, the far-field intensity output of a single main lobe is produced.

Table 1 The phase of the phase compensation plate in one cycle at z ₁ distance

Claims (5)

1. A two-dimensional fiber laser array phase-locking and aperture filling device, including a total reflection mirror (1), a single-mode fiber array (2), a pump source (3), a phase compensation plate (4) and a partial reflection/output Mirror (5), characterized in that: The total reflection mirror (1), the single-mode fiber array (2), the phase compensation plate (4) and the partial reflection/output mirror (5) are sequentially arranged along the optical axis; The single-mode fiber array (2) is formed by arranging a plurality of single-mode fibers, and its cross section has a symmetrical two-dimensional grid structure. One end of the single-mode fiber array (2) is close to the The total reflection mirror (1) mentioned above, the other end is the output end, the diameter of the core of each single-mode fiber is d, and the periods of the two orthogonal directions are T _1x and T _1y respectively, defining the occupation of the two orthogonal directions of the fiber array The empty ratios are d/T _1x and d/T _1y respectively; The pumping source (3) is composed of a plurality of semiconductor laser diodes; Each single-mode fiber in the single-mode fiber array (2) is connected to a semiconductor laser diode in the pump source (3) to form a laser pumping relationship; The distance _Z1 from the output end face of the single-mode fiber array (2) to the phase compensation plate (4) satisfies the Talbot effect self-imaging condition: ${\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}{{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}\frac{{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}{{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}\frac{{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}}$ Among them: α _1x , β _1x and α _1y , β _1y are coprime positive integers, λ is the laser wavelength, and the reciprocal T _1x /d of the duty cycle in two orthogonal directions T 1x /d=β _1x , T _1y / d=β _1y is an integer, then a first-class amplitude pure phase distribution light field will be produced in Z ₁ ; The transmittance function t(x, y) of the phase compensation plate (4) is the complex conjugate function of the equal-amplitude pure-phase distribution light field at the _z1 place; The distance between the phase compensation plate (4) and the partial reflection/output mirror (5) satisfies the Talbot self-imaging and Lau effect conditions: $\frac{z_1{z}_2}{z_1+z_2}=\frac{{\mathrm{\&alpha;}}_{2x}}{{\mathrm{\&beta;}}_{2x}}\frac{T_{2x}^2}{\mathrm{\&lambda;}}=\frac{{\mathrm{\&alpha;}}_{2\mathrm{the\; y}}}{{\mathrm{\&beta;}}_{2\mathrm{the\; y}}}\frac{T_{2\mathrm{the\; y}}^2}{\mathrm{\&lambda;}}$ z ₂ >>z ₁ In the formula: α _2x , β _2x and α _2y , β _2y are all relatively prime positive integers, and z ₂ is the distance from the phase compensation plate (4) to the partial reflection/output mirror (5). 2. A two-dimensional fiber laser array phase-locking and aperture filling device, including a single-mode fiber array (2), a pump source (3), a phase compensation plate (4) and a partial reflection/output mirror (5), its characteristics in: A single-mode fiber array (2), a phase compensation plate (4) and a partial reflection/output mirror (5) are sequentially arranged along the optical axis; The single-mode optical fiber array (2) is formed by arranging a plurality of single-mode optical fibers, and its cross section has a symmetrical two-dimensional lattice structure. One end of the single-mode optical fiber array (2) is plated with total reflection film, the other end is the output end, the diameter of each single-mode fiber core is d, the periods of the two orthogonal directions are T _1x and T _1y respectively, and the duty cycles of the two orthogonal directions of the fiber array are defined as d/T _1x and d/T _1y ; The pumping source (3) is composed of a plurality of semiconductor laser diodes; Each single-mode fiber in the single-mode fiber array (2) is connected to a semiconductor laser diode in the pump source (3) to form a laser pumping relationship; The distance _Z1 from the output end face of the single-mode fiber array (2) to the phase compensation plate (4) satisfies the Talbot (Talbot) effect self-imaging condition: ${\mathrm{<span\; class="notranslate">\; z</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}{{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}\frac{{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; x</span>}}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}{{\mathrm{<span\; class="notranslate">\; \&beta;</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}\frac{{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; the\; y</span>}}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; \&lambda;</span>}}$ Among them: α _1x , β _1x and α _1y , β _1y are coprime positive integers, λ is the laser wavelength, and the reciprocal T _1x /d of the duty cycle in two orthogonal directions T 1x /d=β _1x , T _1y / d=β _1y is an integer, then a first-class amplitude pure phase distribution light field will be produced in Z ₁ ; The transmittance function t(x, y) of the phase compensation plate (4) is the complex conjugate function of the equal-amplitude pure-phase distribution light field at the _z1 place; The distance between the phase compensation plate (4) and the partial reflection/output mirror (5) satisfies the Talbot self-imaging and Lau effect conditions: $\frac{z_1{z}_2}{z_1+z_2}=\frac{{\mathrm{\&alpha;}}_{2x}}{{\mathrm{\&beta;}}_{2x}}\frac{T_{2x}^2}{\mathrm{\&lambda;}}=\frac{{\mathrm{\&alpha;}}_{2\mathrm{the\; y}}}{{\mathrm{\&beta;}}_{2\mathrm{the\; y}}}\frac{T_{2\mathrm{the\; y}}^2}{\mathrm{\&lambda;}}$ z ₂ >>z ₁ In the formula: α _2x , β _2x and α _2y , β _2y are all relatively prime positive integers, and z ₂ is the distance from the phase compensation plate (4) to the partial reflection/output mirror (5). 3. The two-dimensional fiber laser array phase-locking and aperture filling device according to claim 1 or 2, characterized in that the output end of the single-mode fiber laser array (2) is coated with an anti-reflection film. 4. The two-dimensional fiber laser array phase-locking and aperture filling device according to claim 1, characterized in that the cross-section of the single-mode fiber array (2) is an equilateral triangle, square, rectangle, circle or hexagon . 5. The two-dimensional fiber laser array phase-locking and aperture filling device according to claim 2, characterized in that the cross-section of the single-mode fiber array (2) is an equilateral triangle, square, rectangle, circle or hexagon .

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