CN211907938U

CN211907938U - A Fiber Laser to Improve Utilization of Edge Beam

Info

Publication number: CN211907938U
Application number: CN202020507869.6U
Authority: CN
Inventors: 王哲; 丁坦; 梁卓文; 潘东晟
Original assignee: Fourth Military Medical University FMMU
Current assignee: Air Force Medical University
Priority date: 2020-04-08
Filing date: 2020-04-08
Publication date: 2020-11-10
Anticipated expiration: 2030-04-08

Abstract

The utility model discloses a fiber laser for improving the utilization rate of edge beams, comprising a first pumping source array, a first beam combiner, a first reflection grating, a gain fiber, a second reflection grating, a second A beam combiner, a second pump source array and a collimator, wherein the first pump source array includes several first pump sources, each of which is combined with the first The second pump source array includes a plurality of second pump sources, each of which is connected to the second beam combiner through an optical path; the collimator includes a window Glass and collimating lens set. The fiber laser provided by the utility model improves the utilization rate of light by improving the single pumping source into a plurality of symmetrical pumping sources, and using the lens combination as the collimator at the same time.

Description

Fiber laser for improving utilization rate of edge light beam

Technical Field

The utility model belongs to the technical field of laser, concretely relates to improve fiber laser of marginal light beam utilization ratio.

Background

Laser is another important invention of human beings following nuclear energy, computers and semiconductors. The color filter has the characteristics of high brightness, strong directivity, good monochromaticity, strong coherence and the like, and is widely applied to the aspects of engineering manufacture, medical treatment, traffic, communication and the like. A laser is a device capable of emitting laser light.

With the development of science and technology, various lasers appear, wherein the optical fiber laser has wide application prospects in different fields due to the advantages of good beam quality, high efficiency, good heat dissipation and high reliability, and the optical fiber laser comprises laser fiber communication, laser space long-distance communication, industrial shipbuilding, automobile manufacturing, laser engraving, laser marking, laser cutting, military and national defense safety, medical instrument and equipment and the like. In general, a fiber laser is mainly composed of a pump source, a beam combiner, a resonant cavity, a gain fiber, and the like.

However, with the increasing application scenes of the fiber laser, different application scenes also put higher requirements on the performance of the fiber laser, such as conversion efficiency, and the like, while the existing laser mostly adopts a single-pump source structure, which limits the absorption and utilization of light to a certain extent; in addition, the collimating system of the existing fiber laser cannot well utilize some marginal beams, and the problem of low utilization rate of light also exists.

SUMMERY OF THE UTILITY MODEL

In order to solve the above problems existing in the prior art, the utility model provides an improve fiber laser of marginal beam utilization ratio. The to-be-solved technical problem of the utility model is realized through following technical scheme:

a fiber laser for improving the utilization rate of edge beams comprises a first pump source array, a first beam combiner, a first reflection grating, a gain fiber, a second reflection grating, a second beam combiner, a second pump source array and a collimator which are connected in turn through an optical path,

the first pumping source array comprises a plurality of first pumping sources, and each first pumping source is connected with the first beam combiner through an optical path; the second pumping source array comprises a plurality of second pumping sources, and each second pumping source is connected with the second beam combiner through an optical path;

the collimator comprises window glass and a collimating lens group.

In one embodiment of the present invention, the first pump source and the second pump source have the same wavelength.

In an embodiment of the present invention, a heat dissipation mechanism is disposed at the lens of the first pump source and the lens of the second pump source.

In an embodiment of the present invention, the first combiner and the second combiner are both an optical fiber combiner or a wavelength division multiplexer.

In one embodiment of the present invention, the gain fiber is a rare earth doped fiber or a photonic crystal fiber.

In an embodiment of the present invention, the rare earth element includes one or more of ytterbium, cerium, praseodymium, neodymium, samarium, europium, holmium, erbium, thulium, and the like.

In an embodiment of the present invention, the collimating lens group includes a first lens group and a second lens group which are sequentially disposed from left to right.

In an embodiment of the present invention, the first lens group includes a plurality of sequentially arranged meniscus lenses, wherein the concave surface of the meniscus lens is an incident surface of light, and the convex surface of the meniscus lens is an emergent surface of light.

In an embodiment of the present invention, the second lens group includes an aspheric lens, wherein the concave surface of the aspheric lens is an incident surface of light, and the aspheric surface of the aspheric lens is an emergent surface of light.

In another embodiment of the present invention, the second lens group includes a plano-convex lens, wherein the plane of the plano-convex lens is an incident plane of light, and the convex surface of the plano-convex lens is an emergent plane of light.

The utility model has the advantages that:

the utility model provides an improve fiber laser of marginal beam utilization ratio adopts the lens combination to improve the collimater simultaneously through improving a plurality of pumping sources for the symmetry with single pumping source, has further improved the utilization ratio of light.

The present invention will be described in further detail with reference to the accompanying drawings and examples.

Drawings

Fig. 1 is a schematic structural diagram of an optical fiber laser for improving utilization rate of an edge beam according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a collimating system provided by an embodiment of the present invention;

fig. 3 is a schematic structural diagram of another collimation system provided by the embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to specific examples, but the present invention is not limited thereto.

Example one

Referring to fig. 1, fig. 1 is a schematic structural diagram of a fiber laser for improving utilization rate of an edge beam according to an embodiment of the present invention, including: a first pumping source array 1, a first beam combiner 2, a first reflection grating 3, a gain fiber 4, a second reflection grating 5, a second beam combiner 6, a second pumping source array 7 and a collimator 8 which are connected in turn by an optical path,

the first pump source array 1 comprises a plurality of first pump sources, and each first pump source is connected with the first beam combiner 2 through an optical path; the second pump source array 7 comprises a plurality of second pump sources, and each second pump source is connected with the second beam combiner 6 through an optical path;

the collimator 8 comprises a window glass 81, a collimating lens group 82 and an optical fiber joint 83.

Further, the first pump source is a forward pump source, the second pump source is a backward pump source, and the wavelengths of the first pump source and the second pump source are the same.

Optionally, the wavelengths of the first pump source and the second pump source adopt 976nm pump light sources.

In this embodiment, the bidirectional multi-pump source is adopted to balance the thermal load of the light and avoid the local temperature of the system from being too high.

Further, heat dissipation mechanisms are arranged at the positions of the lenses of the first pumping source and the second pumping source.

In this embodiment, because a plurality of pumping sources are adopted, when the operating time of the laser is too long, a large amount of heat can be generated, so that the equipment generates heat, and the reliability of the instrument is improved by adopting a heat dissipation mechanism to absorb a part of heat.

Further, the first combiner 2 and the second combiner 6 are also called a forward combiner and a reverse combiner, respectively, and are both optical fiber combiners or wavelength division multiplexers.

Further, the first reflection grating 3 and the second reflection grating 5 form a resonant cavity of the fiber laser, and the gain fiber 4 is located in the resonant cavity. The resonant cavity is used for selecting light with a certain frequency and consistent direction for the most preferential amplification, and suppressing light with other frequencies and directions.

Further, the first reflective grating 3 is also called a high-reflection grating, which may be a plane mirror or a spherical mirror, and the reflectivity of the mirror surface is close to 100%, also called a total reflection mirror or a high reflection mirror; the second reflection grating 5 is also called a low reflection grating, and may be a plane mirror or a spherical mirror, whose specular reflectivity is slightly lower, so that the laser is output from this mirror, so it is called an output mirror, also called a low reflection mirror.

Further, the gain fiber 4 is also called an active fiber, and is mainly drawn by doping rare earth ions in light. The active fiber is used for realizing the conversion of a pump wavelength to a laser wavelength under the excitation of a pump source.

Specifically, the gain fiber 4 is a rare earth doped fiber or a photonic crystal fiber.

Further, the rare earth elements comprise one or more of ytterbium, cerium, praseodymium, neodymium, samarium, europium, holmium, erbium, thulium and the like.

Further, the collimating lens group 81 includes a first lens group and a second lens group sequentially arranged from left to right.

Further, the first lens group comprises a plurality of meniscus lenses which are arranged in sequence, wherein the concave surface of each meniscus lens is an incident surface of light, and the convex surface of each meniscus lens is an emergent surface of light.

Further, the second lens group includes an aspheric lens, where a concave surface of the aspheric lens is an incident surface of light, and an aspheric surface of the aspheric lens is an exit surface of light.

The following description will discuss the collimating system by taking an example in which the first lens group is a meniscus lens L1 and the second lens group is an aspherical lens L2.

Please refer to fig. 2, fig. 2 is a schematic structural diagram of a collimating system according to an embodiment of the present invention, a light beam generated by a resonant cavity penetrates through window glass to form a diverging light beam, and the diverging light beam sequentially passes through a lens L1 and a lens L2 to be collimated, wherein the lens L1 generates a large refraction to a paraxial edge light beam, and has a large numerical aperture and a strong laser power; lens L2 effectively balances the spherical aberration of lens L1.

The collimator of the embodiment improves the light passing efficiency of the optical system through the combined action of the lens L1 and the lens L2, so that the collimated light beam has a smaller divergence angle.

In another embodiment of the present invention, the second lens group may be a plano-convex lens, wherein the plane of the plano-convex lens is an incident plane of light, and the convex surface of the plano-convex lens is an emergent plane of light.

The following description will discuss the collimating system by taking the first lens group as two meniscus lenses L1, L2 and the second lens group as one plano-convex lens L3.

Please refer to fig. 3, fig. 3 is a schematic structural diagram of another collimating system according to an embodiment of the present invention, a light beam generated by a resonant cavity penetrates through window glass to form a diverging light beam, and the diverging light beam sequentially passes through lenses L1, L2 and a plano-convex lens L3 to be collimated, wherein the lens L1 and the lens L2 generate large refraction for paraxial edge light, have a large numerical aperture, and have strong laser capability; the plano-convex lens L3 effectively balances the spherical aberration of the lens L1 and the lens L2, improves the light passing efficiency of the optical system, and enables the collimated light beam to have a smaller divergence angle.

Further, in order to make the outgoing light a collimated light beam, an incident light source of a collimator may be disposed at the front focus of the collimating lens group.

The foregoing is a more detailed description of the present invention, taken in conjunction with the specific preferred embodiments thereof, and it is not intended that the invention be limited to the specific embodiments shown and described. To the utility model belongs to the technical field of ordinary technical personnel, do not deviate from the utility model discloses under the prerequisite of design, can also make a plurality of simple deductions or replacement, all should regard as belonging to the utility model discloses a protection scope.

Claims

1. a kind of fiber laser improving the utilization ratio of edge beam, it is characterized in that, comprise the first pump source array (1), the first beam combiner (2), the first reflection grating (3), the first pump source array (1), the first beam combiner (2), the first reflection grating (3) that are connected by the optical path successively, A gain fiber (4), a second reflection grating (5), a second beam combiner (6), a second pump source array (7) and a collimator (8), wherein,

The first pump source array (1) includes a plurality of first pump sources, each of which is connected to the first beam combiner (2) through an optical path; the second pump source The source array (7) includes a plurality of second pump sources, each of which is connected to the second beam combiner (6) through an optical path;

The collimator (8) includes a window glass (81) and a collimating lens group (82).

2 . The fiber laser according to claim 1 , wherein the wavelengths of the first pump source and the second pump source are the same. 3 .

3 . The fiber laser according to claim 2 , wherein a heat dissipation mechanism is provided at the lenses of the first pump source and the second pump source. 4 .

4 . The fiber laser according to claim 1 , wherein the first beam combiner ( 2 ) and the second beam combiner ( 6 ) are both fiber combiners or wavelength division multiplexers. 5 .

5 . The fiber laser according to claim 1 , wherein the gain fiber ( 4 ) is an optical fiber doped with rare earth elements or a photonic crystal fiber. 6 .

6. The fiber laser according to claim 1, characterized in that, the collimating lens group (82) comprises a first lens group and a second lens group arranged in sequence from left to right.

7 . The fiber laser according to claim 6 , wherein the first lens group comprises several meniscus lenses arranged in sequence, wherein the concave surface of the meniscus lens is the incident surface of light, and the The convex surface of the meniscus lens is the light exit surface.

8 . The fiber laser according to claim 6 , wherein the second lens group comprises an aspherical lens, wherein the concave surface of the aspherical lens is the incident surface of light, and the non-spherical surface of the aspherical lens The spherical surface is the exit surface of the light.

9 . The fiber laser according to claim 6 , wherein the second lens group comprises a plano-convex lens, wherein the plane of the plano-convex lens is the incident surface of light, and the convex surface of the plano-convex lens is the light incident surface. 10 . exit surface.