Double-grating external cavity spectrum beam combining device

Abstract

The invention relates to a double-grating external cavity spectrum beam combining device. The device comprises a semiconductor laser array light source, a fast axis collimating mirror, a slow axis collimating mirror, an optical path compensation device, a diffraction grating pair, a collimating lens and an output coupling mirror which are arranged in sequence. The optical path compensation device comprises a plurality of optical path compensation assemblies, and the optical path compensation assemblies are in one-to-one correspondence with sub light beams in the array light beams. An optical path compensation assembly is installed in an independent optical path transmission path of each sub-beam of the array beam, the outer cavity length and the beam combining efficiency of each sub-beam are changed through the optical path compensation assemblies, and specifically, the optical path of each sub-beam can be increased through the design that a reflection assembly installation platform drives a reflection assembly to move upwards, so that the beam combining efficiency is improved. Therefore, the length of the outer cavity is increased, the beam combining efficiency is improved, and the stability and precision of the system can be improved. And finally, the cylindrical lens can compensate optical errors introduced in a light beam transmission process, so that each sub-light beam is ensured to have good wavefront uniformity and phase consistency.

Description

Technical Field

[0001] The present application relates to the technical field of laser beam combining, and in particular to a double-grating external cavity spectral beam combining device. Background Art

[0002] High-power semiconductor lasers have the characteristics of lightweight, maintenance-free and high reliability, and have broad application prospects in the fields of intelligent equipment manufacturing, medical treatment and communication. The double-grating spectrum combining structure is a spectrum combining technology widely used in high-power semiconductor lasers. This structure can suppress feedback crosstalk between adjacent sub-units and avoid beam quality degradation through dispersion compensation, thereby achieving narrow linewidth output. However, since this structure uses two gratings, the beam combining efficiency after the light beam passes through the grating external cavity is lost compared to the traditional spectrum combining structure. The beam combining efficiency is an important indicator for evaluating the quality of the external cavity semiconductor laser spectrum combining system, and the optical path (external cavity length) of the light beam propagating in the grating external cavity will affect the beam combining efficiency. Therefore, when the optical elements used in the structure are determined, adjusting the external cavity length is the key to solving the loss of beam combining efficiency.

[0003] At present, the main ways to adjust the length of the external cavity are: (1) increasing the length of the external cavity by adjusting the inherent optical elements in the structure, but it is easy to destroy the optical alignment, introduce additional stray light and energy loss, resulting in reduced efficiency and beam quality. (2) adding an acousto-optic modulator, but it will introduce higher losses and reduce system stability. (3) adding liquid crystal optical devices. Although liquid crystal optical devices have dynamic adjustment and high precision characteristics, they have problems such as high energy loss, small optical path adjustment range and high cost. Summary of the invention

[0004] In order to at least to some extent overcome the problems of high energy loss and poor system stability of the double-grating spectral beam combining structure in the related art when adjusting the external cavity length, the present application provides a double-grating external cavity spectral beam combining device.

[0005] The scheme of this application is as follows:

[0006] A double-grating external cavity spectral beam combining device, comprising:

[0007] A semiconductor laser array light source, a fast axis collimator, a slow axis collimator, an optical path compensation device, a diffraction grating pair, a collimator lens and an output coupling mirror are arranged in sequence;

[0008] The semiconductor laser array light source is used to emit an array light beam, so that the array light beam passes through a rear fast axis collimator, a slow axis collimator, an optical path compensation device, a diffraction grating pair, a collimator lens and an output coupling mirror in sequence;

[0009] Wherein, the optical path compensation device comprises: a plurality of optical path compensation components, and the optical path compensation components correspond one by one to each sub-beam in the array beam;

[0010] The optical path compensation component includes: a reflection component, a reflection component mounting platform, a right-angle reflection prism, a prism bracket, a cylindrical lens and a cylindrical lens bracket;

[0011] The reflective component mounting platform includes two relatively vertical mounting surfaces;

[0012] The reflective assembly comprises a first reflective assembly and a second reflective assembly, and the first reflective assembly and the second reflective assembly are respectively arranged on two mounting surfaces of the reflective assembly mounting platform;

[0013] The right-angle reflecting prism comprises a bottom surface, and a first reflecting surface and a second reflecting surface which are relatively perpendicular to each other;

[0014] The first reflection component is parallel to and opposite to the first reflection surface of the right-angle reflection prism, and the second reflection component is parallel to and opposite to the second reflection surface of the right-angle reflection prism;

[0015] Based on the light beam transmission path, the cylindrical lens is arranged at a rear position of the reflection component and the right-angle reflection prism;

[0016] The sub-beams of the array light beam are refracted in sequence on the first reflection surface of the right-angle reflection prism, the first reflection component, the second reflection component and the second reflection surface of the right-angle reflection prism, and then transmitted to the cylindrical lens;

[0017] The prism support supports the right-angle reflection prism;

[0018] The cylindrical lens support supports the cylindrical lens;

[0019] The reflective component mounting platform drives the reflective component to move up and down through a transmission mechanism to perform optical path compensation on the sub-beams in the array beam.

[0020] Preferably, the cylindrical lens support drives the cylindrical lens to move left and right through a transmission mechanism to collimate the array light beam after optical path compensation.

[0021] Preferably, the first reflective component is arranged at an angle of 135° relative to the incident direction of the array light beam;

[0022] The second reflective component is arranged at an angle of 45° relative to the incident direction of the array light beam.

[0023] Preferably, the fast axis collimator and the slow axis collimator are arranged perpendicularly to the incident direction of the array light beam;

[0024] The fast axis collimator and the slow axis collimator are used to collimate the incident array light beam.

[0025] Preferably, the diffraction grating pair is arranged tilted relative to the incident direction of the array light beam;

[0026] The diffraction grating pair is used to combine the array light beams after optical path compensation.

[0027] Preferably, the collimating lens and the output coupling mirror are arranged perpendicularly to the incident direction of the combined light beam output by the diffraction grating;

[0028] The collimating lens is used to collimate the combined light beam;

[0029] The output coupling mirror is used to couple the collimated combined light beam to output.

[0030] Preferably, it also includes: a collimating lens bracket;

[0031] The collimating lens bracket is used for supporting the collimating lens.

[0032] Preferably, the rear cavity surface of the semiconductor laser array light source and the output coupling mirror form a laser resonant external cavity.

[0033] Preferably, the first reflective component, the second reflective component, the first reflective surface of the right-angle reflective prism and the second reflective surface of the right-angle reflective prism are all coated with a reflective film layer.

[0034] The technical solution provided by this application may have the following beneficial effects:

[0035] The double-grating external cavity spectral beam combining device in the present application comprises: a semiconductor laser array light source, a fast axis collimator, a slow axis collimator, an optical path compensation device, a diffraction grating pair, a collimating lens and an output coupling mirror arranged in sequence; the semiconductor laser array light source is used to emit an array light beam, so that the array light beam passes through the rear fast axis collimator, the slow axis collimator, the optical path compensation device, the diffraction grating pair, the collimating lens and the output coupling mirror in sequence; wherein the optical path compensation device comprises: a plurality of optical path compensation components, and the optical path compensation components correspond to each sub-beam in the array light beam one by one; the optical path compensation component comprises: a reflection component, a reflection component mounting platform, a right-angle reflection prism, a prism bracket, a cylindrical lens and a cylindrical lens bracket; the reflection component mounting platform comprises two relatively vertical mounting surfaces; the reflection component comprises a first reflection component and a second reflection component, and the first reflection component and the second reflection component The components are respectively arranged on two mounting surfaces of the reflective component mounting platform; the right-angle reflective prism includes a bottom surface, and a first reflective surface and a second reflective surface that are relatively vertical; the first reflective component is parallel to and opposite to the first reflective surface of the right-angle reflective prism, and the second reflective component is parallel to and opposite to the second reflective surface of the right-angle reflective prism; based on the light beam transmission path, the cylindrical lens is arranged at the rear position of the reflective component and the right-angle reflective prism; the sub-beams of the array light beam are refracted in turn on the first reflective surface of the right-angle reflective prism, the first reflective component, the second reflective component and the second reflective surface of the right-angle reflective prism, and then transmitted to the cylindrical lens; the prism bracket supports the right-angle reflective prism; the cylindrical lens bracket supports the cylindrical lens; the reflective component mounting platform drives the reflective component to move up and down through a transmission mechanism to perform optical path compensation on the sub-beams in the array light beam.

[0036] In the present technical solution, an optical path compensation component is installed in each independent optical path transmission path of each sub-beam of the array light beam, and the external cavity length and beam combining efficiency of each sub-beam are changed by the optical path compensation component. Specifically, the design of driving the reflective component to move upward by the reflective component mounting platform can increase the optical path of the sub-beam, thereby increasing the external cavity length and improving the beam combining efficiency. At the same time, the reflective component and the right-angle reflective prism adopt the principle of mirror reflection to efficiently reflect the light beam and reduce the loss of light intensity. In addition, the relative arrangement of the reflective component and the right-angle reflective prism can ensure that the light beam reflected by the second reflective surface of the right-angle reflective prism is still transmitted along the predetermined optical path, which can improve the stability and accuracy of the system. Finally, the design of introducing a cylindrical lens in the optical path compensation component can compensate for the optical error introduced during the light beam transmission process, thereby ensuring that each sub-beam has good wavefront uniformity and phase consistency.

[0037] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0039] Figure 1 It is a structural schematic diagram of a double-grating external cavity spectral beam combining device provided by an embodiment of the present application;

[0040] Figure 2 It is a schematic diagram of an optical path compensation component in a double-grating external cavity spectral beam combining device provided by an embodiment of the present application;

[0041] Figure 3 This is a schematic diagram of an optical path of an array light beam passing through an optical path compensation device provided by an embodiment of the present application;

[0042] Figure 4 It is a schematic diagram showing that the beam combining efficiency shows periodic variation with the increase of the external cavity length provided by an embodiment of the present application.

[0043] Figure numerals: semiconductor laser array light source-1; fast axis collimator-2; slow axis collimator-3; optical path compensation device-4; reflection component-403; reflection component mounting platform-404; right-angle reflection prism-405; first reflection surface of right-angle reflection prism-405(1); second reflection surface of right-angle reflection prism-405(2); prism holder-406; cylindrical lens-407; cylindrical lens holder-408; diffraction grating pair-5; collimator lens-6; output coupling mirror-7; collimator lens holder-8. DETAILED DESCRIPTION

[0044] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0045] Figure 1 is a schematic diagram of a dual-grating external cavity spectral beam combining device provided by an embodiment of the present application, referring to Figure 1 , a double-grating external cavity spectral beam combining device, comprising:

[0046] A semiconductor laser array light source 1, a fast axis collimator 2, a slow axis collimator 3, an optical path compensation device 4, a diffraction grating pair 5, a collimator lens 6 and an output coupling mirror 7 are arranged in sequence;

[0047] The semiconductor laser array light source 1 is used to emit an array light beam, so that the array light beam passes through a rear fast axis collimator 2, a slow axis collimator 3, an optical path compensation device 4, a diffraction grating pair 5, a collimator lens 6 and an output coupling mirror 7 in sequence;

[0048] Among them, refer to Figure 2 The optical path compensation device 4 includes: a plurality of optical path compensation components, each of which corresponds to each sub-beam in the array beam;

[0049] The optical path compensation component includes: a reflection component 403, a reflection component mounting platform 404, a right-angle reflection prism 405, a prism bracket 406, a cylindrical lens 407 and a cylindrical lens bracket 408;

[0050] The reflective assembly mounting platform 404 includes two relatively vertical mounting surfaces;

[0051] The reflection component 403 includes a first reflection component and a second reflection component, and the first reflection component and the second reflection component are respectively arranged on two mounting surfaces of the reflection component mounting platform 404;

[0052] The right-angle reflecting prism 405 includes a bottom surface, and a first reflecting surface and a second reflecting surface which are relatively perpendicular to each other;

[0053] The first reflection component is parallel to and opposite to the first reflection surface 405(1) of the right-angle reflection prism, and the second reflection component is parallel to and opposite to the second reflection surface 405(2) of the right-angle reflection prism;

[0054] Based on the light beam transmission path, the cylindrical lens 407 is arranged at a rear position of the reflection component 403 and the right-angle reflection prism 405;

[0055] The sub-beams of the array light beam are refracted in sequence by the first reflection surface 405 (1) of the right-angle reflection prism, the first reflection component, the second reflection component and the second reflection surface 405 (2) of the right-angle reflection prism, and then transmitted to the cylindrical lens 407;

[0056] The prism support 406 supports the right-angle reflection prism 405;

[0057] The cylindrical lens support 408 supports the cylindrical lens 407;

[0058] The reflective component mounting platform 404 drives the reflective component 403 to move up and down through a transmission mechanism to perform optical path compensation on the sub-beams in the array beam.

[0059] like Figure 1As shown, the optical components are arranged in the order of the beam transmission path, which are semiconductor laser array light source 1, fast axis collimator 2, slow axis collimator 3, optical path compensation device 4, diffraction grating pair 5, collimator lens 6 and output coupling mirror 7. Among them, the semiconductor laser array light source 1, fast axis collimator 2, slow axis collimator 3, diffraction grating pair 5, collimator lens 6 and output coupling mirror 7 are conventional optical components in the prior art and are not described in detail here.

[0060] Figure 3 is a schematic diagram of the optical path of the array beam passing through the optical path compensation device 4, as shown in Figure 3 As shown, an optical path compensation component is installed in each independent optical path transmission path of each sub-beam to accurately adjust the transmission path of each light beam and improve the beam combining efficiency. The semiconductor laser array light source 1 includes a plurality of light-emitting sub-units, each light-emitting sub-unit is arranged at equal intervals, 100, 101 and 102 are the central sub-unit and the end sub-units on both sides of the semiconductor laser array, respectively, and 400, 401 and 402 are the light beams emitted by the sub-units 100, 101 and 102, respectively.

[0061] Taking the light beam transmission of light beam 400 as an example, light beam 400 is collimated by fast axis collimator 2 and slow axis collimator 3 and then vertically incident on the first reflection surface 405(1) of the right angle reflection prism. The first reflection surface 405(1) of the right angle reflection prism reflects the vertically incident light beam to the first reflection component, which is then reflected by the first reflection component to the second reflection component, and then reflected by the second reflection component to the second reflection surface 405(2) of the right angle reflection prism. It is then reflected and output by the second reflection surface 405(2) of the right angle reflection prism, and finally output after being collimated and compensated by cylindrical lens 407.

[0062] It should be noted that the length of the external cavity after each sub-beam in the semiconductor laser array light source 1 passes through the grating external cavity is L EC And the beam combining efficiency η m Determined by the following formula:

[0063]

[0064] Assuming that the laser energy emitted by each sub-beam of the semiconductor laser array is the same, the beam combining efficiency of the 2m+1 beam after passing through the grating external cavity is:

[0065]

[0066] Where f is the distance from the semiconductor laser array light source 1 to the first central subunit, m·Δp is the distance between the mth subunit and the central subunit, α0 represents the incident angle of the central subunit with a wavelength of λ0, h1 is the grating spacing, and z is the transmission distance. κ m is the external cavity feedback strength parameter, ω m =2πc / λm is the oscillation frequency of the mth subunit in the semiconductor laser array light source 1 in the external cavity, τ EC =2L EC / c is the round trip time of photons in the external cavity, G N is the differential gain coefficient, τ IC =2nL IC / c is the round trip time of photons in the cavity, R = J / (eV) is the carrier injection rate per unit volume, τ c is the carrier lifetime, N T =N0+1 / (G N τ p ) is the threshold carrier density, R3 is the equivalent reflectivity of the external cavity, τ c is the photon lifetime.

[0067] When the incident angle is the Littrow angle, according to the grating equation, the incident angle of the central subunit with a wavelength of λ0 can be expressed as:

[0068]

[0069] Where λ0 is the central subunit wavelength and d is the grating period.

[0070] It can be seen from the above formula that adjusting the length of the external cavity is the key to solving the loss of beam combining efficiency.

[0071] In this embodiment, the semiconductor laser array light source 1 is used to emit an array light beam, so that the array light beam passes through the rear fast axis collimator 2, the slow axis collimator 3, the optical path compensation device 4, the diffraction grating pair 5, the collimator lens 6 and the output coupling mirror 7 in sequence, and the rear cavity surface of the semiconductor laser array light source 1 and the output coupling mirror 7 form a laser resonant external cavity.

[0072] In this technical solution, the reflective component 403 is installed on the reflective component installation platform 404, and the reflective component installation platform 404 drives the reflective component 403 to move up and down through a transmission mechanism, and realizes the return of the light path and achieves optical path compensation by changing the transmission direction of the sub-beam.

[0073] Preferably, the reflective assembly 403 is moved slightly in sections, so that the optical path of the sub-beam increases by only 50nm each time, and the beam combining efficiency is recorded when the optical path of each sub-beam increases by 50nm, and the changing trend of the beam combining efficiency is observed until the beam combining efficiency of the beam reaches a peak value, and the total optical path increased at this time is recorded and the total external cavity length when the beam combining efficiency reaches the peak value is calculated. Finally, the total beam combining efficiency after the external cavity length is adjusted is calculated by the formula.

[0074] In specific practice, the following records should be kept when adjusting the optical path compensation device 4: first, adjust the reflective component mounting platform 404 to the initial position to reset it, and calculate the external cavity length and beam combining efficiency of each sub-beam transmitted in the external cavity at this time; secondly, Figure 3 Move the reflective assembly mounting platform 404 in the direction of the arrow shown in the figure and adjust the cylindrical lens 407 appropriately, record the beam combining efficiency when the optical path of each sub-beam increases by 50nm, and observe the changing trend of the beam combining efficiency until the beam combining efficiency reaches the peak value, and record the total optical path ΔL increased at this time EC And calculate the external cavity length (L EC +ΔL EC ), where L EC is the initial external cavity length. Finally, the total beam combining efficiency after the external cavity length is adjusted is calculated by the formula.

[0075] Reference Figure 4 , the semiconductor laser array light source 1 includes 21 light-emitting units.

[0076] like Figure 4 As shown in the figure, the calculated bundle combining efficiency of the terminal subunit and the central subunit varies with the length of the external cavity; Figure 4 The figure above shows the variation of the beam combining efficiency of the -10th subunit with the length of the external cavity; Figure 4 The middle graph is a graph showing the beam combining efficiency of the central subunit as a function of the external cavity length; Figure 4 The figure below shows the beam combining efficiency of the 10th subunit as a function of the length of the external cavity. EC is the length of the external cavity for the light beam to propagate in the external cavity, η m is the beam combining efficiency of the mth subunit, the hollow points are the beam combining efficiency before adding the optical path compensation device 4, and the solid points are the peak beam combining efficiency after increasing the external cavity length. Before adding the optical path compensation device 4, the beam combining efficiencies of the -10th subunit, the central subunit, and the 10th subunit were 67.29%, 69.12%, and 71.36%, respectively. After adding the optical path compensation device 4 to increase the external cavity length of the light beam, they all reached their peak beam combining efficiency of 72.56%.

[0077] like Figure 4 As shown, the beam combining efficiency changes periodically with the increase of the external cavity length. The maximum beam combining efficiency of each sub-unit is 72.56%, and the minimum is 66.57%. The beam combining efficiency of 21 light beams after passing through the grating external cavity is 69.13%. When the optical path compensation device 4 is added, the external cavity length of each sub-beam is increased. At this time, the beam combining efficiency of 21 light beams after passing through the grating external cavity is increased to 72.56%.

[0078] The above practice proves that the technical solution increases the propagation optical path of each sub-beam in the grating external cavity through the optical path compensation device 4, improves the beam combining efficiency of each sub-beam, thereby improving the overall beam combining efficiency, and can provide an effective way to solve the efficiency loss in double grating spectrum combining.

[0079] In one achievable manner of this embodiment, the cylindrical lens support 408 drives the cylindrical lens 407 to move left and right through a transmission mechanism, so as to collimate the array light beam after optical path compensation.

[0080] Preferably, in this embodiment, the cylindrical lens holder 408 is used to drive the cylindrical lens 407 to move left and right, so as to collimate each sub-beam to ensure good wavefront uniformity and phase consistency.

[0081] Preferably, the first reflective component is arranged at an angle of 135° relative to the incident direction of the array light beam;

[0082] The second reflective component is arranged at an angle of 45° relative to the incident direction of the array light beam.

[0083] The first reflective component, the second reflective component, the first reflective surface 405 (1) of the right-angle reflective prism, and the second reflective surface 405 (2) of the right-angle reflective prism are all coated with a reflective film layer.

[0084] The first reflective component is arranged at an angle of 135° relative to the incident direction of the array light beam, so that the first reflective surface 405(1) of the right-angle reflective prism is also at an angle of 135° relative to the incident direction of the array light beam; the second reflective component is arranged at an angle of 45° relative to the incident direction of the array light beam, so that the second reflective surface 405(2) of the right-angle reflective prism is also at an angle of 45° relative to the incident direction of the array light beam.

[0085] It should be noted that the first reflective component, the second reflective component, the first reflective surface 405 (1) of the right-angle reflective prism and the second reflective surface 405 (2) of the right-angle reflective prism are all coated with a reflective film layer with high reflectivity, so that the single-side reflectivity can be greater than 99% when the incident angle is 45°.

[0086] In specific practice, the fast axis collimator 2 and the slow axis collimator 3 are arranged perpendicularly to the incident direction of the array light beam;

[0087] The fast axis collimator 2 and the slow axis collimator 3 are used to collimate the incident array light beam.

[0088] The fast-axis collimator 2 and the slow-axis collimator 3 are arranged perpendicularly to the incident direction of the array light beam, that is, the fast-axis collimator 2 and the slow-axis collimator 3 are parallel to each other. The fast-axis collimator 2 and the slow-axis collimator 3 are used to collimate the array light beam emitted by the semiconductor laser array light source 1 in the fast-axis and slow-axis directions, respectively, and then the collimated light beam is incident on the first reflection surface 405(1) of the right-angle reflection prism.

[0089] It should be noted that, refer to Figure 1 , the diffraction grating pair 5 is tilted relative to the incident direction of the array beam;

[0090] The diffraction grating pair 5 is used to combine the array light beams after optical path compensation.

[0091] The diffraction grating pair 5 is tilted relative to the incident direction of the array beam in order to combine the array beam after the optical path compensation. The diffraction grating pair 5 includes two diffraction gratings parallel to each other. Figure 1 The diffraction grating on the left side is used to combine the array light beams output from the second reflection surface 405 (2) of the right-angle reflection prism. Figure 1 The diffraction grating on the right side of the center is used to output the combined light beam.

[0092] It should be noted that the collimating lens 6 and the output coupling mirror 7 are arranged perpendicularly to the incident direction of the combined light beam output by the diffraction grating;

[0093] The collimating lens 6 is used to collimate the combined light beam;

[0094] The output coupling mirror 7 is used to couple the collimated combined light beam to output.

[0095] The collimating lens 6 and the output coupling mirror 7 are arranged perpendicularly to the incident direction of the combined light beam output by the diffraction grating, and the collimating lens 6 and the output coupling mirror 7 are parallel to each other.

[0096] The collimating lens 6 is used to collimate the combined light beam and reduce the divergence angle of the combined light beam so that the divergence angle is kept small during the propagation process, thereby maintaining the parallelism and coherence of the light beam over a long distance.

[0097] Further, such as Figure 1 As shown, the double-grating external cavity spectral beam combining device further includes: a collimating lens bracket 8;

[0098] The collimating lens holder 8 is used to support the collimating lens 6 .

[0099] In this embodiment, the collimating lens 6 is fixed by the collimating lens bracket 8, and the collimating lens 6 does not need to be moved.

[0100] In summary, in the present technical solution, an optical path compensation component is installed in each independent optical path transmission path of each sub-beam of the array light beam, and the external cavity length and beam combining efficiency of each sub-beam are changed by the optical path compensation component. Specifically, the design of driving the reflective component 403 to move upward by the reflective component mounting platform 404 can increase the optical path of the sub-beam, thereby increasing the external cavity length and improving the beam combining efficiency. At the same time, the reflective component 403 and the right-angle reflective prism 405 adopt the principle of mirror reflection to efficiently reflect the light beam and reduce the loss of light intensity. In addition, the relative arrangement of the reflective component 403 and the right-angle reflective prism 405 can ensure that the light beam reflected by the second reflective surface 405 (2) of the right-angle reflective prism is still transmitted along the predetermined optical path, which can improve the stability and accuracy of the system. Finally, the design of introducing the cylindrical lens 407 in the optical path compensation component can compensate for the optical error introduced during the light beam transmission process, thereby ensuring that each sub-beam has good wavefront uniformity and phase consistency.

[0101] It can be understood that the same or similar parts of the above embodiments can be referenced to each other, and the contents not described in detail in some embodiments can refer to the same or similar contents in other embodiments.

[0102] It should be noted that, in the description of this application, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of this application, unless otherwise specified, the meaning of "plurality" refers to at least two.

[0103] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0104] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A dual-grating external cavity spectral beam combining device, characterized in that: include: A semiconductor laser array light source, a fast axis collimator, a slow axis collimator, an optical path compensation device, a diffraction grating pair, a collimator lens and an output coupling mirror are arranged in sequence; The semiconductor laser array light source is used to emit an array light beam, so that the array light beam passes through a rear fast axis collimator, a slow axis collimator, an optical path compensation device, a diffraction grating pair, a collimator lens and an output coupling mirror in sequence; Wherein, the optical path compensation device comprises: a plurality of optical path compensation components, and the optical path compensation components correspond one by one to each sub-beam in the array beam; The optical path compensation component includes: a reflection component, a reflection component mounting platform, a right-angle reflection prism, a prism bracket, a cylindrical lens and a cylindrical lens bracket; The reflective component mounting platform includes two relatively vertical mounting surfaces; The reflective assembly comprises a first reflective assembly and a second reflective assembly, and the first reflective assembly and the second reflective assembly are respectively arranged on two mounting surfaces of the reflective assembly mounting platform; The right-angle reflecting prism comprises a bottom surface, and a first reflecting surface and a second reflecting surface which are relatively perpendicular to each other; The first reflection component is parallel to and opposite to the first reflection surface of the right-angle reflection prism, and the second reflection component is parallel to and opposite to the second reflection surface of the right-angle reflection prism; Based on the light beam transmission path, the cylindrical lens is arranged at a rear position of the reflection component and the right-angle reflection prism; The sub-beams of the array light beam are refracted in sequence on the first reflection surface of the right-angle reflection prism, the first reflection component, the second reflection component and the second reflection surface of the right-angle reflection prism, and then transmitted to the cylindrical lens; The prism support supports the right-angle reflection prism; The cylindrical lens support supports the cylindrical lens; The reflective component mounting platform drives the reflective component to move up and down through a transmission mechanism to perform optical path compensation on the sub-beams in the array beam.

2. The dual-grating external cavity spectral beam combining device according to claim 1, characterized in that: The cylindrical lens support drives the cylindrical lens to move left and right through a transmission mechanism to collimate the array light beam after optical path compensation.

3. The dual-grating external cavity spectral beam combining device according to claim 1, characterized in that: The first reflective component is arranged at an angle of 135° relative to the incident direction of the array light beam; The second reflective component is arranged at an angle of 45° relative to the incident direction of the array light beam.

4. The dual-grating external cavity spectral beam combining device according to claim 3, characterized in that: The fast axis collimator and the slow axis collimator are arranged perpendicularly to the incident direction of the array light beam; The fast axis collimator and the slow axis collimator are used to collimate the incident array light beam.

5. The dual-grating external cavity spectral beam combining device according to claim 4, characterized in that: The diffraction grating pair is tilted relative to the incident direction of the array light beam; The diffraction grating pair is used to combine the array light beams after optical path compensation.

6. The dual-grating external cavity spectral beam combining device according to claim 5, characterized in that: The collimating lens and the output coupling mirror are arranged perpendicularly to the incident direction of the combined light beam output by the diffraction grating; The collimating lens is used to collimate the combined light beam; The output coupling mirror is used to couple the collimated combined light beam to output.

7. The dual-grating external cavity spectral beam combining device according to claim 1, characterized in that: Also includes: Collimating lens holder; The collimating lens bracket is used for supporting the collimating lens.

8. The dual-grating external cavity spectral beam combining device according to claim 1, characterized in that: The rear cavity surface of the semiconductor laser array light source and the output coupling mirror form a laser resonant external cavity.

9. The dual-grating external cavity spectral beam combining device according to claim 1, characterized in that: The first reflection component, the second reflection component, the first reflection surface of the right-angle reflection prism and the second reflection surface of the right-angle reflection prism are all coated with a reflection film layer.

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