CN118315911A - Semiconductor pumping thin-sheet laser distributed along space sphere - Google Patents

Abstract

The invention discloses a semiconductor pumping thin-sheet laser distributed along a space sphere, which comprises: a thin sheet laser crystal; the device comprises a heat sink and one or more layers of edge-emitting semiconductor laser arrays, wherein each layer of edge-emitting semiconductor laser array comprises a plurality of edge-emitting semiconductor laser arrays, and light-emitting surfaces of the edge-emitting semiconductor laser arrays are uniformly distributed along the intersecting line of a spherical surface and a plane; the light emitting directions of the side emitting semiconductor lasers are all directed to the center of the sphere; the coupling-out mirror is arranged on the central axis of the thin-sheet laser crystal and is parallel to the high-reflection surface, wherein the high-reflection surface of the thin-sheet laser crystal is plated with a high-reflection film which reflects light beams with two wavelengths of output laser and pump laser so as to form a laser resonant cavity with the coupling-out mirror; the sphere center is the center of the flake laser crystal, and the plane is parallel to the high-reflection surface; the diameter of the intersection line is larger than the diameter of the coupling-out lens.

Description

Semiconductor pumping thin-sheet laser distributed along space sphere

Technical Field

The invention relates to a semiconductor pumping thin-sheet laser distributed along a space spherical surface, belonging to the technical field of semiconductor lasers.

Background

An edge-emitting semiconductor laser (EEL) is a commonly used pump source of a high-power solid laser, which is used for irradiating and exciting lower-level particles in a laser crystal to an upper level, and finally realizing the population inversion and the laser output. As shown in fig. 5, the edge-emitting semiconductor laser is a linear high-power semiconductor laser light source constituted by horizontally arranging one or more light emitting points. Among them, the edge-emitting semiconductor laser of a single die is called an edge-emitting single die, and the array of a plurality of dies is often called a laser bar. The edge-emitting semiconductor laser has two different divergence angles in the vertical direction and the horizontal direction, which are called a fast axis and a slow axis, respectively. The half-width of the fast axis divergence angle is about 30-40 degrees, and the half-width of the slow axis divergence angle is about 6-10 degrees. A typical edge-emitting semiconductor laser has an overall width of about 10mm, but other different widths are also possible. Because the divergence angle in the fast axis direction is larger, an aspheric cylindrical lens (also called a fast axis compression lens) is generally adopted for compression, and the divergence angle after compression can be smaller than 0.5 degrees or even lower. The divergence angle in the slow axis direction can be further compressed, and the compression is generally performed by adopting an aspherical cylindrical lens array in one-to-one correspondence (also called slow axis compression lens). Since the stripe width of each die in the horizontal direction is typically several tens to several hundreds of micrometers, the divergence angle compression ratio in the slow axis direction is low.

Common solid state laser pumping structures include pumping from the side of the laser crystal (relative to the laser oscillation direction) or from the end of the laser crystal, referred to as side pumping structures and end pumping structures, respectively. The light-emitting surface pumping is a more common pumping mode, and is particularly suitable for a thin-sheet laser crystal with a large absorption coefficient. Aiming at the end-face pumping structure, in the Chinese utility model with the patent number ZL 202020592548.0, an LD direct pumping frequency conversion semiconductor thin-sheet laser is disclosed. The semiconductor slice laser comprises a pumping module, an optical collimation focusing system, a quantum gain slice, a nonlinear frequency conversion crystal and a coupling output cavity mirror; the optical collimation focusing system projects the light beam emitted by the LD pumping module onto the quantum gain sheet; the nonlinear frequency conversion crystal performs frequency conversion on fundamental frequency laser emitted by the quantum gain sheet, and the output frequency range of the coupling-out cavity mirror covers laser beams from ultraviolet to near infrared bands; through the optical collimation focusing system, LD (laser diode) is used for direct pumping, complex optical fiber coupling in optical fiber coupling output pumping can be omitted, meanwhile, the shape and the size of a pumping light spot projected on a quantum gain sheet can be flexibly adjusted according to actual needs, the beam quality is improved, meanwhile, the space of a laser is greatly saved, and the integration and the miniaturization of the laser are facilitated. However, in this type of design, the number of pump sources is small, and high-power lasers cannot be satisfied.

In addition, as described above, the light emission of the edge-emitting semiconductor laser and the array formed by the same is not a circular spot (stripe light emission), but the thin-sheet laser crystal adopts a circular symmetrical structure (such as a wafer or a regular polygon) in many cases, so that there is a difficulty in matching between the two.

Disclosure of Invention

The invention aims to provide a semiconductor pumping thin-sheet laser distributed along a space spherical surface.

In order to achieve the technical purpose, the invention adopts the following technical scheme:

A semiconductor pumped thin film laser distributed along a spatial spherical surface, comprising:

A thin-sheet laser crystal excited by the optical pump to generate a laser gain;

a heat sink soldered or crimped with the highly reflective surface of the thin sheet laser crystal to provide heat dissipation,

One or more layers of edge-emitting semiconductor laser arrays, each layer of edge-emitting semiconductor laser array comprising a plurality of edge-emitting semiconductor laser arrays, the light-emitting surfaces of the edge-emitting semiconductor laser arrays of the same layer being uniformly distributed along the intersection line of the spherical surface and the plane; the side-emitting semiconductor laser array comprises a plurality of side-emitting semiconductor lasers, and the light emitting direction of each side-emitting semiconductor laser is directed to the center of the sphere; and

A coupling-out mirror disposed on a central axis of the thin-sheet laser crystal and parallel to the highly anti-surface,

The high-reflection surface of the thin-sheet laser crystal is plated with a high-reflection film which reflects light beams with two wavelengths of output laser and pump laser so as to form a laser resonant cavity with the coupling output mirror;

the sphere center is the center of the thin-sheet laser crystal, and the plane is parallel to the high-reflection surface;

the diameter of the intersection line is larger than the diameter of the coupling-out lens.

Wherein preferably the edge-emitting semiconductor laser array comprises a first layer edge-emitting semiconductor laser array and a second layer edge-emitting semiconductor laser array,

The first layer edge emitting semiconductor laser array and the second layer edge emitting semiconductor laser array are located on intersecting lines of different planes and the spherical surface.

Wherein preferably each edge-emitting semiconductor laser in the first layer edge-emitting semiconductor laser array is identical;

Each edge-emitting semiconductor laser in the second layer edge-emitting semiconductor laser array is identical,

The edge-emitting semiconductor lasers in the first layer edge-emitting semiconductor laser array are different from the edge-emitting semiconductor lasers in the second layer edge-emitting semiconductor laser array.

Preferably, the arrangement direction of the edge-emitting semiconductor lasers in the first layer of edge-emitting semiconductor laser array is the same as that of the slow axis;

the side-emitting semiconductor lasers in the second layer of side-emitting semiconductor laser array are arranged in the same arrangement direction as the side-emitting semiconductor laser array on the fast axis.

Preferably, the edge emitting semiconductor laser array of the same layer takes the central point of the thin-sheet laser crystal as the center to form radiation symmetrical pump absorption distribution with strong center and weak edge.

Preferably, in the edge emitting semiconductor laser arrays of the same layer, each edge emitting semiconductor laser array is arranged in a straight line, the broadband in the arrangement direction is L, the divergence half angle of the fast axis or the slow axis in the arrangement direction is θ, the spherical radius is R, and the diameter of the laser crystal sheet is D, so that D is greater than or equal to N and n=l+2×r×tan (θ) is satisfied.

Wherein each of the edge emitting semiconductor lasers is preferably fast axis compressed using a fast axis compression lens and maintains a divergence angle consistent with an initial spot size.

Wherein, preferably, an antireflection film for outputting laser and pumping laser is plated on the light emergent surface of the sheet laser crystal.

Wherein, preferably, a coating film is formed on the coupling-out mirror to enhance the power density distribution intensity of the output light beam with strong center and weak edge.

Wherein preferably, a coating film is formed on the coupling-out mirror, so that the transmittance is gradually changed from the center to the edge, and an output light spot with flat top light intensity is obtained.

Compared with the prior art, the invention uses the spherically symmetrical distributed multi-layer edge-emitting semiconductor laser array as a pumping source to realize a high-power laser; moreover, as the pump source is spherically symmetrical, the matching property of the strip-shaped emergent pump light spots and the circular thin sheet is improved, so that the uniform light spots with strong middle and weak periphery which are approximately symmetrical to circular radiation can be realized; the design of the edge-emitting semiconductor lasers of different layers can be used for realizing various output beams, and the application range is enlarged.

Drawings

FIG. 1 is a schematic view of an optical path structure of a semiconductor pump thin-film laser distributed along a spatial spherical surface in a first embodiment of the present invention;

FIG. 2 is an enlarged schematic view of the thin-sheet laser crystal of FIG. 1;

FIG. 3A is a side view of the distribution of the same layer edge-emitting semiconductor laser array in a first embodiment of the present invention;

FIG. 3B is a top view of the distribution of the same layer edge-emitting semiconductor laser array in a first embodiment of the present invention;

FIG. 3C is a schematic view of a beam projection of an array of edge-emitting semiconductor lasers according to a first embodiment of the present invention;

FIG. 4A is a side view of the profile of the same layer edge-emitting semiconductor laser array in a second embodiment of the present invention;

FIG. 4B is a top view of the distribution of the same layer edge-emitting semiconductor laser array in a second embodiment of the present invention;

FIG. 4C is a schematic view of a beam projection of an edge-emitting semiconductor laser array according to a second embodiment of the present invention;

fig. 5 is a schematic diagram of the fast and slow axes of light emission of an edge emitting semiconductor laser according to the prior art.

Detailed Description

The technical contents of the present invention will be described in detail with reference to the accompanying drawings and specific examples.

The technical conception in the embodiment of the invention is to use a spherically symmetrical distributed multi-layer edge-emitting semiconductor laser array as a pumping source to realize a high-power laser. Moreover, since the pump source is spherically symmetric, a uniform spot with a strong middle and a weak periphery, which is approximately circular (multi-petal-shaped) can be realized. In addition, the projection relation of the pumping light spots on the sheet laser crystal is utilized, and the matching performance of the strip-shaped light-emitting pumping light spots and the circular sheet is improved.

First embodiment

As shown in fig. 1, the semiconductor pump thin-film laser distributed along the space spherical surface provided by the first embodiment of the present invention includes a thin-film laser crystal 10, a heat sink 11 for dissipating heat from the thin-film laser crystal, a multi-layer edge-emitting semiconductor laser array, and a coupling-out mirror 5. The semiconductor pumped thin film lasers distributed along the spatial spherical surface are packaged together with a heat sink on the substrate 12.

As shown in fig. 1 and 2, the sheet laser crystal 10 is generally circular or regular polygonal (e.g., regular pentagonal, regular hexagonal, or regular octagonal) and has a thickness of about several hundred micrometers to several millimeters. The thin-sheet laser crystal is made of YAG crystal or ceramic material doped with neodymium and ytterbium, and can generate laser gain after being excited by optical pumping, and the thin-sheet laser crystal is matched with a resonant cavity to form solid laser. The thin-film laser crystal is coated with a high reflection film (HR film 15) on the side close to the heat sink, and an antireflection film (AR film 14) on the side close to the pump. In a thin-sheet solid-state laser, an edge-emitting semiconductor laser array (EEL) is a commonly used pump source for exciting a laser crystal.

A thin sheet laser crystal 10 which is well soldered or crimped with the heat sink 11 to dissipate heat through the heat sink 11. A highly reflective film (HR film 15) reflecting light beams of both wavelengths of the output laser light and the pump laser light is coated on a highly reflective surface 101 of the sheet laser crystal 10 facing the heat sink 11; an antireflection film (AR film 14) for outputting laser light and pumping laser light is coated on the other surface (light-emitting surface) of the sheet laser crystal 10.

In the light-emitting direction of the sheet laser crystal 10, a coupling-out mirror 5 is provided at a position spaced apart from the sheet laser crystal by a predetermined distance. The coupling-out mirror 5 is located on the axis of the thin-film laser crystal 10 and parallel to the highly anti-surface of the thin-film laser crystal 10 to form a laser resonator with the HR film 15.

One or more layers of the edge-emitting semiconductor laser arrays provided in the embodiments of the present invention are illustrated in fig. 1 by taking a first layer of the edge-emitting semiconductor laser array 1 (hereinafter referred to as EEL 1) and a second layer of the edge-emitting semiconductor laser array 2 (hereinafter referred to as EEL 2) as examples, but this is not a limitation of the present invention. For example, in theory, one or more layers of edge-emitting semiconductor lasers may be edge-emitting single dies, or arrays of edge-emitting semiconductor lasers (laser bars).

Wherein, the light emergent surface of each EEL 1 is uniformly distributed on the intersection line 100 of the first plane C and the spherical surface; the light-emitting surfaces of the EELs 2 are uniformly distributed on the intersection line 100 of the second plane B and the spherical surface. That is, the light emitting surfaces of the edge emitting semiconductor laser arrays of the same layer are uniformly distributed on the intersecting line 100 of the same plane and the spherical surface, and the plane is parallel to the high-reflection plane 101 of the thin-sheet laser crystal 10, and the spherical center of the spherical surface is the center point of the thin-sheet laser crystal 10.

Specifically, in fig. 1, a broken line circle represents a spherical surface, and the center thereof is the center point of the thin-sheet laser crystal 10; the dashed line a represents plane a, which represents the high-reflection plane 101; the dashed line B represents the second plane B and the dashed line C represents the first plane C, both of which are parallel to the plane a. In the drawing, the light emitting surfaces of the EELs 1 are located at the intersection point of the dashed line C and the dashed circle, i.e. the intersection line 100 of the first plane C and the spherical surface. Similarly, the light emitting surfaces of the EELs 2 are located at the intersection point of the dashed line B and the dashed circle in the figure, that is, the intersection line 100 of the second plane B and the spherical surface. Such a design ensures that the distances from the light exit surfaces of all the edge-emitting semiconductor lasers of the same layer to the center point of the sheet laser crystal 10 are equal, and the edge-emitting semiconductor lasers of the same layer are uniformly distributed on the annular intersection line 100, so that the light beams of all the edge-emitting semiconductor lasers of the same layer are incident on the uniform light spot formed by the sheet laser crystal 10, and the radiation symmetry is presented by taking the center point of the sheet laser crystal 10 as the center. I.e. spot consistency and center symmetry.

In addition, the EEL 1 and the EEL2 are located in different layers, and the light beams thereof are incident on the sheet laser crystal 10, so that the formed spots are not identical. If EEL 1 and EEL2 are edge-emitting semiconductor lasers of the same specification and are arranged in the same manner, since the spherical latitudes of the two are different (i.e., the distances from the first plane C and the second plane B to the plane a are different), the beam of EEL 1 is incident on the spot diameter of the thin-sheet laser crystal 10, which is smaller than the spot diameter of the beam of EEL2 incident on the thin-sheet laser crystal 10, but the spot of EEL 1 and the spot of EEL2 are both centered on the center point of the thin-sheet laser crystal 10, so that the superposition effect of the spot of EEL 1 and the spot of EEL2 is shown: near the center point of the thin-film laser crystal 10, a circular spot with a large power density is formed, and a spot with a relatively small power density is formed on the outer periphery. In other words, the pump absorption profile with strong center and weak edge is formed with the center point of the thin-film laser crystal 10 as the center.

In one embodiment of the present invention, as shown in fig. 3A to 3C, each of the edge emitting semiconductor lasers in the same layer is arranged in the following manner: each side-emitting semiconductor laser performs fast axis compression by using a fast axis compression lens, and keeps the divergence angle consistent with the initial spot size; and the slow axis can be compressed or not according to the size of the thin-sheet laser crystal and the pumping distance, and only the beam direction of the compressed edge-emitting semiconductor laser is required to be ensured to point to the central point of the thin-sheet laser crystal 10, and the divergence angles of the fast axis and the slow axis are all preset angles.

Specifically, a multilayer side-emitting semiconductor laser is provided on the light-emitting surface side of the sheet laser crystal 10; the plurality of edge emitting semiconductor lasers of each layer are uniformly distributed on the annular intersection line 100, and the beam center of the outgoing light is directed to the center point of the sheet laser crystal 10; the slow axis of the plurality of edge-emitting semiconductor lasers of the same layer coincides with the direction of the linear arrangement of the edge-emitting semiconductor laser array (bars) (bars are linearly arranged in the horizontal direction, and slow axis is also in the horizontal direction).

Based on the foregoing placement of the edge-emitting semiconductor laser, how to calculate the projection of the edge-emitting semiconductor laser is described below.

In the edge-emitting semiconductor laser arrays of the same layer, each edge-emitting semiconductor laser array is arranged in a straight line, the broadband in the arrangement direction is L, the divergence half angle of the fast axis or the slow axis in the arrangement direction is theta, the spherical radius is R, and the diameter of the laser crystal sheet is D, so that the requirement that D is more than or equal to N and N=L+2 is R tan (theta) is met.

Taking the placement of fig. 3C as an example, in the direction perpendicular to the light emitting surface (in the direction from top to bottom in fig. 1), the broad band of the edge-emitting semiconductor laser array arranged in a straight line is L, the slow axis divergence half angle is θ1, the spherical radius is R, and the diameter of the laser crystal sheet 10 (circular in the figure) is D, so that d+.m and m=l+2r×tan (θ1) (1) are satisfied.

Since the fast axis direction is perpendicular to the slow axis, i.e., perpendicular to the arrangement direction of the edge-emitting semiconductor laser arrays, and the fast axis is compressed by the fast axis compression lens, the projection of the light beam in the fast axis direction of one edge-emitting semiconductor laser array (shown in fig. 3A) is smaller than the projection of the light beam in the slow axis direction (shown in fig. 3B). Therefore, if the diameter of the laser crystal sheet 10 is ensured to satisfy the expression 1, it is ensured that the diameter D of the laser crystal sheet 10 is necessarily larger than the projection area of the light beam on the fast axis. And will not be discussed in detail herein.

The out-coupling mirror 5 is arranged on the central axis of the thin-film laser crystal 10. The coupling-out mirror 5 is parallel to the highly reflective surface 101 and outputs a beam portion reflected by the thin-film laser crystal 10, thereby forming a laser resonator with the highly reflective film (HR film 15). It should be noted that the diameter of the intersection line is larger than the diameter of the coupling-out lens 5, so as to avoid that any one of the edge emitting semiconductor lasers affects the light emission.

Preferably, in order to form a gaussian laser output, the coupling-out mirror 5 is coated with a uniform antireflection film, and is an output beam with strong center and weak edge.

Preferably, for the case of solid laser output expected to obtain approximately flat-top distribution, a coupling output mirror (also called Gao Sijing) with gradually-changed transmittance design can be adopted, so that the light intensity distribution with strong center and weak edge is corrected into an output light spot with approximately flat-top light intensity.

It will be appreciated by those skilled in the art that other adjustments may be made to the output beam by coating the output coupling mirror 5 as desired, based on the pump absorption profile with strong center and weak edges.

In summary, the semiconductor pump thin-film laser distributed along the space sphere provided by the embodiment of the invention has the following technical effects:

1) By arranging the multi-layer edge-emitting semiconductor laser array, the power of the output light beam can be increased, and a high-power laser is provided; and the more the number of layers, the greater the power;

2) The edge-emitting semiconductor laser arrays of each layer are uniformly distributed on the annular intersecting line, so that the matching problem of the strip-shaped emergent pumping light spots and the circular thin sheet is solved, and radial symmetrical pumping light can be formed to ensure the uniformity of the output light beam;

3) Providing a pump light source with strong center and weak edge by utilizing projection superposition of edge-emitting semiconductor laser arrays of different layers; the power density distribution intensity of the output light beam with strong center and weak edge can be further enhanced by combining the coating of the coupling-out mirror. In other words, according to the output beam power density distribution required by practical application, a proper number of layers can be selected, and the specification of the edge-emitting semiconductor laser array and the specification of the coating film are selected, so that more design space is provided for realizing or adjusting various output beam power density distributions or beam quality and the like so as to meet various practical requirements;

4) And obtaining an output light spot with light intensity similar to a flat top by adopting a coupling output mirror with a transmissivity gradual change design.

Second embodiment

The difference between the present embodiment and the first embodiment is that the arrangement of the edge emitting semiconductor laser array is different, and the remaining identical parts will not be described again.

In the present embodiment, as shown in fig. 4A and 4B, the side-emitting semiconductor laser arrays are aligned in a straight line, and the fast axis direction is the same as the alignment direction (the slow axis direction is the same as the alignment direction in the first embodiment).

As described above, with respect to one edge-emitting semiconductor laser array, the light output in the fast axis direction through the fast axis compression lens has been compressed, and the projection onto the sheet laser crystal 10 satisfies:

Referring to fig. 4C, the broadband of the edge-emitting semiconductor laser array arranged in a straight line is L, the fast axis divergence half angle is θ2, the spherical radius is R, and the diameter of the laser crystal sheet 10 (circular in the figure) is D, so that D is equal to or greater than N and n=l+2×r×tan (θ2) (2) is satisfied.

The edge-emitting semiconductor laser array thus arranged in this embodiment may also be used for the semiconductor pump thin-sheet lasers distributed along the spatial spherical surface provided in the embodiment of the present invention.

Therefore, in the semiconductor pump thin-film laser distributed along the space spherical surface provided by the embodiment of the invention, each edge-emitting semiconductor laser in the first layer edge-emitting semiconductor laser array is the same; the individual edge-emitting semiconductor lasers in the second layer edge-emitting semiconductor laser array are identical, but the edge-emitting semiconductor lasers in the first layer edge-emitting semiconductor laser array are different from the edge-emitting semiconductor lasers in the second layer edge-emitting semiconductor laser array.

For example, the side-emitting semiconductor lasers in the first layer side-emitting semiconductor laser array are placed in such a manner that the slow axis is the same as the arrangement direction of the side-emitting semiconductor laser array. However, the side-emitting semiconductor lasers in the second layer side-emitting semiconductor laser array are arranged in such a way that the fast axis is the same as the arrangement direction of the side-emitting semiconductor laser array, and vice versa.

For another example, the output power of the edge-emitting semiconductor laser in the first layer edge-emitting semiconductor laser array is different from the output power of the edge-emitting semiconductor laser in the second layer edge-emitting semiconductor laser array.

It should be noted that the above embodiments are only examples, and the technical solutions of the embodiments may be combined, which are all within the protection scope of the present invention. For example, the first layer edge-emitting semiconductor laser array is arranged in the first embodiment (the slow axis is the same as the array arrangement direction); the second layer of emitting semiconductor laser array adopts the setting mode (the fast axis is the same as the array arrangement direction) of the second embodiment, so that the power density distribution of the optical shift can be adjusted or the second layer of emitting semiconductor laser array is suitable for application scenes of different light spots.

The semiconductor pump thin-film laser distributed along the space sphere provided by the invention is described in detail above. Any obvious modifications to the present invention, without departing from the spirit thereof, would constitute an infringement of the patent rights of the invention and would take on corresponding legal liabilities.

Claims (10)

1. A semiconductor pumped thin film laser distributed along a spatial spherical surface, comprising:

A thin-sheet laser crystal excited by the optical pump to generate a laser gain;

a heat sink soldered or crimped with the highly reflective surface of the thin sheet laser crystal to provide heat dissipation,

One or more layers of edge-emitting semiconductor laser arrays, each layer of edge-emitting semiconductor laser array comprising a plurality of edge-emitting semiconductor laser arrays, the light-emitting surfaces of the edge-emitting semiconductor laser arrays of the same layer being uniformly distributed along the intersection line of the spherical surface and the plane; the side-emitting semiconductor laser array comprises a plurality of side-emitting semiconductor lasers, and the light emitting direction of each side-emitting semiconductor laser is directed to the center of the sphere; and

A coupling-out mirror disposed on a central axis of the thin-sheet laser crystal and parallel to the highly anti-surface,

The high-reflection surface of the thin-sheet laser crystal is plated with a high-reflection film which reflects light beams with two wavelengths of output laser and pump laser so as to form a laser resonant cavity with the coupling output mirror;

the sphere center is the center of the thin-sheet laser crystal, and the plane is parallel to the high-reflection surface;

the diameter of the intersection line is larger than the diameter of the coupling-out lens.

2. A spatially spherically distributed semiconductor pumped thin film laser according to claim 1, wherein:

The edge-emitting semiconductor laser array includes a first layer edge-emitting semiconductor laser array and a second layer edge-emitting semiconductor laser array,

The first layer edge emitting semiconductor laser array and the second layer edge emitting semiconductor laser array are located on intersecting lines of different planes and the spherical surface.

3. A spatially spherically distributed semiconductor pumped thin-sheet laser according to claim 2, characterized in that:

Each edge-emitting semiconductor laser in the first layer edge-emitting semiconductor laser array is identical;

Each edge-emitting semiconductor laser in the second layer edge-emitting semiconductor laser array is identical,

The edge-emitting semiconductor lasers in the first layer edge-emitting semiconductor laser array are different from the edge-emitting semiconductor lasers in the second layer edge-emitting semiconductor laser array.

4. A spatially spherically distributed semiconductor pumped thin film laser as claimed in claim 3, wherein:

The arrangement mode of the edge-emitting semiconductor lasers in the first layer of edge-emitting semiconductor laser array is that the slow axis is the same as the arrangement direction of the edge-emitting semiconductor laser array;

the side-emitting semiconductor lasers in the second layer of side-emitting semiconductor laser array are arranged in the same arrangement direction as the side-emitting semiconductor laser array on the fast axis.

5. A spatially spherically distributed semiconductor pump thin-sheet laser according to any one of claims 1 to 4, characterized in that:

The edge-emitting semiconductor laser array of the same layer takes the central point of the thin-sheet laser crystal as the center to form the radiation symmetrical pumping absorption distribution with strong center and weak edge.

6. A spatially spherically distributed semiconductor pumped thin film laser according to claim 5, wherein:

In the edge-emitting semiconductor laser arrays of the same layer, each edge-emitting semiconductor laser array is arranged in a straight line, the broadband in the arrangement direction is L, the divergence half angle of the fast axis or the slow axis in the arrangement direction is theta, the spherical radius is R, and the diameter of the laser crystal sheet is D, so that the requirement that D is more than or equal to N and N=L+2 is R (theta) is met.

7. A spatially spherically distributed semiconductor pumped thin film laser according to claim 6, wherein:

Each of the edge emitting semiconductor lasers performs fast axis compression using a fast axis compression lens and maintains a divergence angle consistent with an initial spot size.

8. A spatially spherically distributed semiconductor pumped thin film laser according to claim 6, wherein:

an antireflection film for outputting laser and pumping laser is coated on the light emergent surface of the thin-sheet laser crystal.

9. A spatially spherically distributed semiconductor pumped thin film laser according to claim 6, wherein:

and a coating film is formed on the coupling-out mirror so as to enhance the power density distribution intensity of the output light beam with strong center and weak edge.

10. A spatially spherically distributed semiconductor pumped thin film laser according to claim 6, wherein:

and a coating film is formed on the coupling-out mirror, so that the transmittance is gradually changed from the center to the edge, and an output light spot with flat top light intensity is obtained.