阅读说明：本技术 一种多单管半导体激光器密集波长合束装置 (Dense wavelength beam combining device of multi-single-tube semiconductor laser ) 是由 秦文斌 郭照师 姜梦华 李景 于 2020-12-10 设计创作，主要内容包括：一种多单管半导体激光器密集波长合束装置,属于激光技术领域。包括：多单管半导体激光器空间合束模块、傅里叶转换透镜、衍射光栅、外腔镜。多个单管半导体激光器线性且相对排列发出初始激光束；通过快慢轴准直镜对激光束准直并利用反射镜反射后形成空间合束激光；利用傅里叶变换透镜对激光束进行傅里叶变换并通过衍射光栅元件使得激光束衍射输出；外腔镜接收到的衍射光一部分反射并与前腔面镀增透膜且反射率<1％的单管半导体激光器形成外腔并锁定波长,另一部分透射出经衍射光栅衍射的激光束。本发明提供了一种多单管半导体激光器密集波长合束装置,解决了线阵式和堆栈式结构的半导体激光器进行密集波长合束带来的光束质量差、亮度低等问题。(An intensive wavelength beam combining device of a multi-single-tube semiconductor laser belongs to the technical field of laser. The method comprises the following steps: the device comprises a space beam combination module of a plurality of single-tube semiconductor lasers, a Fourier transform lens, a diffraction grating and an external cavity mirror. A plurality of single-tube semiconductor lasers are linearly and oppositely arranged to emit initial laser beams; collimating the laser beam by a fast-slow axis collimating mirror and forming a space beam combination laser after reflecting by a reflector; performing Fourier transform on the laser beam by using a Fourier transform lens and enabling the laser beam to be diffracted and output through a diffraction grating element; and one part of the diffracted light received by the external cavity mirror is reflected and forms an external cavity with the single-tube semiconductor laser with the front cavity surface coated with an antireflection film and the reflectivity of less than 1 percent, the wavelength is locked, and the other part of the diffracted light transmits laser beams diffracted by the diffraction grating. The invention provides a dense wavelength beam combining device of a multi-single-tube semiconductor laser, which solves the problems of poor light beam quality, low brightness and the like caused by dense wavelength beam combining of semiconductor lasers with linear array and stack structures.)

1. A dense wavelength beam combining device of a multi-single-tube semiconductor laser is characterized by comprising a multi-single-tube semiconductor laser space beam combining module (1), a Fourier transform lens (2), a diffraction grating (3) and an external cavity mirror (4);

the multi-single-tube semiconductor laser spatial beam combination module (1) is composed of a plurality of single-tube semiconductor lasers (101), a fast axis collimating mirror (102), a slow axis collimating mirror (103) and a reflecting mirror (104); the single-tube semiconductor lasers are linearly arranged side by side and are arranged in two opposite rows, a fast-axis collimating mirror (102), a slow-axis collimating mirror (103) and a reflecting mirror (104) are sequentially arranged on the front edge optical axis of a light outlet of each single-tube semiconductor laser, and each single-tube semiconductor laser and the corresponding fast-axis collimating mirror, slow-axis collimating mirror and reflecting mirror are positioned in the center of the same optical axis; the fast axis collimating lens and the slow axis collimating lens are used for collimating laser beams emitted by the single-tube semiconductor laser and can compress divergence angles of the laser beams in two directions of a fast axis and a slow axis; the reflector is used for reflecting the collimated laser beam; all the reflectors corresponding to the single-tube semiconductor lasers are located on the same side of the Fourier transform lens (2), the diffraction grating (3) is arranged on the other side of the Fourier transform lens (2), and an external cavity mirror (4) is arranged behind the diffraction grating (3).

2. A dense wavelength beam combining device of a multi-monotube semiconductor laser as claimed in claim 1, wherein the diffraction grating (3) is transmissive or reflective.

3. A multiple single-tube semiconductor laser dense wavelength beam combining device according to claim 1, characterized in that the laser beams reflected by all the reflectors are spatially uniformly distributed in parallel on the same side of the fourier transform lens (2) and are all incident on the fourier transform lens (2).

4. The dense wavelength beam combining device of claim 1, wherein the single-tube semiconductor laser emits parallel laser beams, and the front cavity surface is coated with an antireflection coating, with a reflectivity of less than 1%.

5. The dense wavelength beam combining device of claim 1, wherein the fourier transform lens is configured to receive the collimated laser beam reflected by the mirror and perform fourier transform.

6. The dense wavelength beam combining device of claim 1, wherein the diffraction grating is disposed at an angle such that the incident angle of the fourier transformed laser beam on the diffraction grating is equal to the diffraction angle thereof, and all the laser beams are diffracted and outputted at the same exit angle and the diffracted and outputted laser beams are made into a single beam.

7. The dense wavelength beam combining device of a multi-single-tube semiconductor laser according to claim 1, wherein the external cavity mirror is a partial reflector, one surface of the external cavity mirror is coated with a reflecting film, the reflectivity of the external cavity mirror is 1% -30%, and the other surface of the external cavity mirror is coated with an antireflection film; the reflector can transmit part of laser beams, and the other part of the laser beams is reflected by the original path to form external cavity feedback with the single-tube semiconductor laser.

Technical Field

The invention relates to the technical field of laser, in particular to a dense wavelength beam combining device of a multi-single-tube semiconductor laser.

Background

The semiconductor laser has the obvious advantages of compact structure, small volume, long service life and high electro-optic conversion efficiency of 50% or even higher. However, the laser development level still limits the application of laser in various fields. Some applications in the field of material processing require laser output with high power and high beam quality, and semiconductor lasers have strict requirements on brightness and wavelength when being used as pumping sources, but the traditional semiconductor laser technology cannot solve the problems, and the laser output with high power, high beam quality and high brightness can be realized by combining the beam combination technology.

Among different types of semiconductor lasers, linear array structures and stack structures can solve the problem of insufficient output power of the semiconductor lasers, but divergence angles of output light beams of the semiconductor lasers are generally large and space brightness is low. Single tube semiconductor lasers have many advantages: the chip has small volume and high reliability, can realize higher power output (the maximum power exceeds 20W), has good beam quality, and does not have the problem of smile effect.

The dense wavelength beam combination realizes the locking of each light-emitting unit at different wavelengths by combining diffraction elements such as a grating and the like with an external cavity mirror, sub-beams with different wavelengths are diffracted on the grating to be combined to output beams, and incident light can be spatially overlapped in a far field and a near field through the diffraction action of the grating. The beam quality of the combined laser beam is similar to that of a single beam combining unit, and the power is the sum of all the beam combining units.

Disclosure of Invention

In view of the above problems, the present invention provides a dense wavelength beam combining device for multiple single-tube semiconductor lasers, so as to solve the problems of poor beam quality and low brightness caused by dense wavelength beam combining using semiconductor lasers with linear array and stacked structures.

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

a dense wavelength beam combining device of a multi-single-tube semiconductor laser is characterized by comprising a multi-single-tube semiconductor laser space beam combining module (1), a Fourier transform lens (2), a diffraction grating (3) and an external cavity mirror (4).

Furthermore, the multi-single-tube semiconductor laser spatial beam combination module (1) is composed of a plurality of single-tube semiconductor lasers (101), a fast axis collimating mirror (102), a slow axis collimating mirror (103) and a reflecting mirror (104); the single-tube semiconductor lasers are linearly arranged side by side and are arranged in two opposite rows, a fast-axis collimating mirror (102), a slow-axis collimating mirror (103) and a reflecting mirror (104) are sequentially arranged on the front edge optical axis of a light outlet of each single-tube semiconductor laser, and each single-tube semiconductor laser and the corresponding fast-axis collimating mirror, slow-axis collimating mirror and reflecting mirror are positioned in the center of the same optical axis; the fast axis collimating lens and the slow axis collimating lens are used for collimating laser beams emitted by the single-tube semiconductor laser and can compress divergence angles of the laser beams in two directions of a fast axis and a slow axis; the reflector is used for reflecting the collimated laser beam; all the reflectors corresponding to the single-tube semiconductor lasers are located on the same side of the Fourier transform lens (2), the diffraction grating (3) is arranged on the other side of the Fourier transform lens (2), and an external cavity mirror (4) is arranged behind the diffraction grating (3).

The diffraction grating (3) may be transmissive or reflective.

The laser beams reflected by all the reflectors are uniformly and parallelly distributed on the same side of the Fourier transform lens (2) in space and are all incident on the Fourier transform lens (2).

The single-tube semiconductor laser can emit parallel laser beams, and the front cavity surface of the single-tube semiconductor laser is coated with an antireflection film, so that the reflectivity is less than 1%.

The Fourier transform lens is used for receiving the collimated laser beam reflected by the reflector and carrying out Fourier transform.

The diffraction grating is arranged at a specific angle, so that the incidence angle of the laser beam subjected to Fourier transform on the diffraction grating is equal to the diffraction angle of the laser beam, all the laser beams are diffracted and output at the same emergence angle, and the diffracted and output laser is made into a single beam.

The external cavity mirror is a partial reflector, one surface of the external cavity mirror is plated with a reflecting film, the reflectivity of the external cavity mirror is 1% -30%, and the other surface of the external cavity mirror is plated with an anti-reflection film. The reflector can transmit part of laser beams, and the other part of the laser beams is reflected by the original path to form external cavity feedback with the single-tube semiconductor laser.

According to the technical scheme, the invention has the advantages that: according to the intensive wavelength beam combining device with the multiple single-tube semiconductor lasers, the single-tube semiconductor lasers are used as beam combining light sources, and the beam quality of the combined laser beams can be improved to a great extent. Meanwhile, a plurality of single pipelines are linearly arranged and arranged into two opposite rows, the divergence angles of the fast and slow axes are compressed by using the fast and slow axis collimating mirrors, and a plurality of reflecting mirrors are used for reflecting laser beams reflected by a plurality of single pipes into a beam of parallel light, so that the power of the laser beams after beam combination is increased.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are needed to be used in the description of the embodiments or the prior art will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and that other drawings can be derived from these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a transmission type grating dense wavelength beam combining device of a multi-single-tube semiconductor laser;

FIG. 2 is a reflection-type grating dense wavelength beam combining device of a multi-single-tube semiconductor laser;

description of the main element symbols:

the laser comprises a 1-multi-single-tube semiconductor laser spatial beam combining module, a 101-single-tube semiconductor laser, a 102-fast axis collimating mirror, a 103-slow axis collimating mirror, a 104-reflecting mirror, a 2-Fourier transform lens, a 3-diffraction grating and a 4-external cavity mirror.

Detailed Description

The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

As shown in fig. 1 and 2, the device is a transmissive and reflective dense wavelength beam combining device with multiple single-tube semiconductor lasers, wherein a spatial beam combining module 1 of the multiple single-tube semiconductor lasers includes a single-tube semiconductor laser 101, a fast-axis collimating mirror 102, a slow-axis collimating mirror 103, and a reflecting mirror 104; the Fourier transform lens 2, the diffraction grating 3 and the external cavity mirror 4 are also included.

In this embodiment, the plurality of single-tube semiconductor lasers 101 are linearly arranged and arranged in two opposite rows to improve the beam quality of the combined laser, the front cavity surface of the single-tube semiconductor laser 101 is coated with an antireflection film, and the cavity surface reflectivity is less than 1%; the fast axis collimating lens 102 and the slow axis collimating lens 103 are both cylindrical lenses and are used for collimating the divergence angle of the laser emitted by the single-tube semiconductor laser 101; the reflector 104 is used for reflecting the collimated laser beams so that all the laser beams are emitted in parallel at equal intervals. The fast axis collimator 102, the slow axis collimator 103 and the mirror 104 are located under the same optical axis.

The laser beam reflected by the reflecting mirror 104 and having an equal interval is incident in parallel to the fourier transform lens 2, and fourier transform processing can be performed on the incident laser beam.

The laser after the fourier transform is focused and enters the diffraction grating 3, and all the beams exit at a diffraction angle after passing through the diffraction grating 3. The diffraction grating 3 is located at the back focus of the fourier transform lens 2 and is placed at a specific angle, the diffraction grating 3 being either transmissive or reflective.

The external cavity mirror 4 is coated with a reflecting film, the reflectivity is 1% -30%, the laser beams diffracted by the diffraction grating 3 can be partially reflected, the reflected light returns to form an external cavity with the single-tube semiconductor laser 101, and different single-tube semiconductor lasers 101 are locked at different wavelengths after the external cavity is locked. Another part of the laser beam will be transmitted through the external cavity mirror 4 as a wavelength-combined laser.