Semiconductor laser device

Abstract

The utility model discloses a semiconductor laser device which comprises a pump light module and a shaping assembly. The pump light module is used for outputting a collimated light beam; the shaping assembly is arranged on an output light path of the collimated light beam and comprises a deformation prism and a focus lens which are arranged in sequence. The deformation prism is used for correcting the collimated light beam, so that the sizes of light spots of the collimated light beam in the slow axis direction and the fast axis direction are consistent; and the focusing lens is used for focusing the collimated light beam corrected by the deformation prism and reducing a light beam divergence angle. According to the semiconductor laser device, shaping of the collimated light beam in the fast axis direction or the slow axis direction is achieved by arranging the deformation prism in the light path, the production cost is reduced, and the overall integration degree of the device is improved.

Description

Technical Field

[0001] This utility model relates to the field of laser technology, and in particular to a semiconductor laser device. Background Technology

[0002] High-power semiconductor lasers have been widely used in numerous fields such as laser cutting, laser welding, laser marking, laser medicine, lidar, and laser weapons. The optical path of a semiconductor laser can be divided into a collimation module, a deflection module (mirror module), and a focusing module. Because the laser emitted from the chip exhibits inconsistent spatial divergence angles (typically, the direction with the larger angle is called the fast axis, and the direction with the smaller angle is called the slow axis), the collimation and focusing modules of a semiconductor laser need to collimate and focus along the fast and slow axes respectively before beam splitting can occur. Furthermore, the collimation and focusing modules often require two or more lenses placed in the optical path to effectively improve the laser beam quality. Increasing the number of lenses correspondingly increases the geometric size of the semiconductor laser, which is detrimental to its integration. Moreover, in the field of high-power lasers, the selection of spherical mirrors is limited by the high power, resulting in a limited focal length and higher cost compared to flat glass processing.

[0003] Therefore, in order to address the problems of high cost and low overall integration of existing high-power semiconductor laser focusing schemes, a new semiconductor laser device needs to be designed. Utility Model Content

[0004] In view of the above-mentioned shortcomings of the prior art, the purpose of this application is to provide a semiconductor laser device to solve the problems of high cost and low overall integration of high-power semiconductor laser focusing schemes in the prior art.

[0005] To achieve the above and other related objectives, this application provides a semiconductor laser device, comprising:

[0006] Pump optical module, used to output collimated beam; and

[0007] A shaping component is disposed on the output optical path of the collimated beam. The shaping component includes a deformable prism and a focusing lens arranged sequentially. The deformable prism is used to correct the collimated beam so that the size of the spot of the collimated beam is consistent in the fast axis direction and the slow axis direction. The focusing lens is used to focus the collimated beam corrected by the deformable prism.

[0008] As a preferred embodiment, the system also includes a coupling fiber, into which the collimated beam, after being shaped by the shaping component, is coupled and output.

[0009] As a preferred embodiment, the deformable prism is a right-angle prism, and the collimated beam is incident from the right-angled surface or the inclined surface of the right-angle prism.

[0010] As a preferred embodiment, the refractive index of the deformable prism is greater than or equal to 1.45, and the transmittance is greater than 95%.

[0011] As a preferred embodiment, the system also includes a housing substrate, on which both the pump light module and the shaping component are disposed.

[0012] As a preferred embodiment, the shaping component further includes a fixing member, through which the deformable prism is fixed to the surface of the housing substrate.

[0013] As a preferred embodiment, the pump light module includes a beam combining component, at least one chip component, and multiple collimation components corresponding to each chip in the chip component. The collimation components are used to convert the pump light emitted from the corresponding chip into a collimated beam.

[0014] The beam combining component is disposed in the output optical path of at least two of the collimated beams, and is used to combine multiple collimated beams to output a single collimated beam.

[0015] As a preferred embodiment, the beam combining assembly includes a polarization beam combiner and a plurality of first spot steering elements, each of the first spot steering elements being used to steering the collimated beam emitted from the collimation assembly toward the polarization beam combiner.

[0016] As a preferred embodiment, at least one chip component includes a first chipset and a second chipset.

[0017] Wherein, the first pump light emitted from the first chip group is transformed into a first collimated beam by the collimation component, and the second pump light emitted from the second chip group is transformed into a second collimated beam by the collimation component;

[0018] The first collimated beam is deflected by the first spot-directing element and then reflected by the polarization combiner before being output along the first direction. The second collimated beam is deflected by the first spot-directing element and then output along the first direction through the polarization combiner.

[0019] As a preferred embodiment, a second beam deflection element is also included, which is disposed in the light output direction of the deformable prism and is used to adjust the output direction of the collimated beam output from the deformable prism.

[0020] In summary, the semiconductor laser device provided in this application includes a pump light module and a shaping component. The pump light module is used to output a collimated beam; the shaping component is disposed in the output optical path of the collimated beam and includes a deformable prism and a focusing lens arranged sequentially. The deformable prism is used to correct the collimated beam, making the size of the collimated beam spot consistent in the slow axis and fast axis directions; the focusing lens is used to focus the collimated beam corrected by the deformable prism, reducing the beam divergence angle. The semiconductor laser device of this application achieves the shaping of the collimated beam in the fast or slow axis direction by setting a deformable prism in the optical path, which is beneficial for reducing production costs and improving the overall integration of the device. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of a semiconductor laser device provided in this application;

[0022] Figure 2 This is a schematic diagram of the output optical path principle of a deformable lens provided in this application.

[0023] The accompanying diagram is described as follows:

[0024] 1. Chip assembly; 11. Chip; 2. Collimation assembly; 3. Beam combining assembly; 4. Shaping assembly; 41. Deformation prism; 42. Focusing lens; 45. Fixing component; 51. First spot turning element; 52. Second spot turning element; 6. Housing substrate. Detailed Implementation

[0025] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the present invention are shown in the drawings, not the entire structure. Various modifications and variations can be made to the present invention without departing from its spirit or scope, which will be apparent to those skilled in the art. Therefore, the present invention is intended to cover modifications and variations falling within the scope of the corresponding claims (the claimed technical solutions) and their equivalents. It should be noted that the embodiments provided by the present invention can be combined with each other without contradiction.

[0026] This utility model provides a semiconductor laser device in view of one or more of the above-mentioned problems existing in the prior art. Figure 1 This is a schematic diagram of a semiconductor laser device provided in this application. Please refer to it. Figure 1The semiconductor laser device provided in this embodiment includes a pump light module and a shaping component. The pump light module is used to output a collimated beam, and the shaping component is disposed on the output optical path of the collimated beam. A collimated beam refers to a beam with a small beam divergence angle, meaning that the beam radius does not significantly change after a certain propagation distance. In this embodiment, the pump light module can be a single chip with good collimation; or it can be multiple chips, whose multiple pump lights are collimated and combined to output a single collimated beam. This embodiment does not impose any limitations. The semiconductor laser device also includes a coupling fiber, into which the collimated beam shaped by the shaping component is coupled and output.

[0027] Please continue to refer to this. Figure 1 Taking a pump light module comprising a beam combiner 3, at least one chip assembly 1, and multiple collimating assemblies 2 corresponding to the chips in that chip assembly as an example. The chip assembly 1 emits pump light, and each chip assembly 1 has several independent chips 11, each chip 11 being an independent light-emitting unit. Taking a two-way chip assembly 1 as an example, the pump light emitted from the chips 11 in the two-way chip assembly 1 is emitted along direction A to the collimating assembly 2, and after being redirected, is transmitted along direction B to the polarization beam combiner 3. Directions A and B are orthogonal.

[0028] Collimation component 2 is disposed in the output optical path of the pump light to convert the pump light into a collimated beam. Typically, the pump light emitted from chip component 1 has a large divergence angle; collimation component 2 is used to collimate the pump light, converting it into a linearly polarized collimated beam. In this embodiment, collimation component 2 may include a fast-axis collimating mirror and a slow-axis collimating mirror arranged sequentially. The fast-axis collimating mirror is disposed close to the light-emitting surface of the corresponding chip and is connected to the optical path of the corresponding slow-axis collimating mirror. The fast-axis collimating mirror is used to collimate the light spot in the fast-axis direction of the laser, and the slow-axis collimating mirror is used to collimate the light spot in the slow-axis direction of the laser.

[0029] For example, the chip assembly of the semiconductor laser device in this embodiment of the present invention can be divided into a double row or a single row arranged along the B direction. The light-emitting centers of each chip in the same row are located on different planes. A fast-axis collimating lens and a slow-axis collimating lens are placed sequentially on each chip 11 along the direction of the light output path. These two can be regarded as a set of steering and compression optical elements. The steering and compression optical elements can steering and compress the collimated beam after passing through the fast-axis collimating lens and the slow-axis collimating lens.

[0030] A beam combiner 3 is disposed in the output optical path of at least two collimated beams to combine multiple collimated beams into a single collimated beam, thereby improving the overall output power of the device. Exemplarily, the beam combiner 3 includes a polarized beam combiner (PBC) and multiple first beam steering elements 51. Each first beam steering element is used to steering the collimated beam emitted from the collimating assembly to the polarized beam combiner. It can be understood that the polarized beam combiner includes a first incident surface and a second incident surface. The first incident surface reflects the incident beam, and the second incident surface transmits the incident beam. The incident beam and the reflected beam are combined in the polarized beam combiner and output in the same direction. At least some of the first beam steering elements 51 are disposed corresponding to the output end of the collimating assembly 2, and are used to receive each collimated beam and reflect and steering it to the first and second incident surfaces of the polarized beam combiner. The polarized beam combiner outputs collimated beams with orthogonal polarization states. The first beam steering elements 51 can be mirrors.

[0031] It should be noted that, in this embodiment of the invention, the polarization beam combiner can be sheet-like or block-like, combining collimated beams of orthogonal polarization incident from the first and second incident surfaces into a single beam. This application does not impose any limitations on this aspect. Figure 1 The example shown here is a block shape only. The shaping component 4 is set in the output optical path of the collimated beam to shape the spot shape of the collimated beam.

[0032] In the embodiments of this application, please continue to refer to Figure 1 The shaping component 4 includes a deformable prism 41 and a focusing lens 42. The deformable prism 41 and the focusing lens 42 are sequentially arranged in the output optical path of the collimated beam. The deformable prism 41 is used to correct the collimated beam so that the size of the collimated beam spot is consistent in the slow axis direction and the fast axis direction.

[0033] Preferably, the deformable prism 41 is a right-angle prism, and the collimated beam output from the pump light module is incident from the right-angle face or the inclined face of the right-angle prism.

[0034] A right-angle prism is an optical element that amplifies an elliptical beam in one dimension, converting the elliptical output beam of a laser diode into a nearly circular beam, and vice versa. As an example, right-angle prisms are typically made of high-quality transparent materials, such as SF11 glass. Their dimensional tolerances are +0.0 / -0.2 mm, aperture is greater than 80%, angle tolerance is ±3 arcmin, surface quality is 60-40 SD, surface flatness is less than λ / 4 @ 632.8 nm, protective chamfer is less than 0.25 mm x 45 degrees, and coatings are available upon request.

[0035] Specifically, refer to Figure 1 The pump light emitted from several chips 11 in chip assembly 1 is first collimated into a collimated beam by the fast-axis collimating lens in collimating assembly 2, and then shaped into a collimated beam by the slow-axis collimating lens. The collimated beams from multiple output paths are stacked in the fast-axis direction and transmitted to beam combining assembly 3. After being combined into a single collimated beam, it is transmitted to the surface of deformable prism 41. Here, the combined collimated beam can be monitored as an irregular rectangular or irregular spot. However, the pump light emitted from each chip 11 in chip assembly 1 is usually elliptical. Deformable prism 41 can expand the collimated beam along the fast axis or shrink it along the slow axis, shaping the emitted spot into an approximately square or circular spot. This spot is then focused by focusing lens 42 and directly output as spatial light or coupled into a coupling fiber for output.

[0036] Figure 2 This is a schematic diagram of the output optical path principle of a deformable prism provided in this application, for reference. Figure 2 The output optical path principle of deformable prism 41 is as follows: The collimated beam (elliptical beam) refracted after passing through deformable prism 41 satisfies Snell's refraction formula: Where θ1 is the angle between the collimated beam and the normal to the incident surface of the deformable prism 41, i.e., the incident angle, θ2 is the refraction angle of the collimated beam at the interface of the deformable prism 41, n0 is the refractive index of air, and n is the refractive index of the deformable prism 41.

[0037] Preferably, the refractive index n of the deformable prism 41 is greater than or equal to 1.45 and the transmittance is greater than 95%. The refractive index of air is 1. Using a deformable prism 41 made of a material with a larger refractive index is beneficial to increasing the optical path of the collimated beam and improving the shaping effect of the light spot.

[0038] It should be noted that the collimated beam can be incident on the right-angled surface of the deformable prism 41, resulting in beam contraction along the fast axis; or, the collimated beam can be incident on the inclined surface of the deformable prism 41, resulting in beam expansion along the slow axis, thus achieving consistent beam spot size in both the slow and fast axis directions. (Reference) Figure 2 This embodiment of the invention is illustrated by taking a collimated beam incident on the inclined surface of the deformable prism 41 and exiting at a right angle as an example. Before the collimated beam is incident on the inclined surface of the deformable prism 41, the slow axis diameter is D1, and the fast axis diameter is D2. After the collimated beam is incident on the inclined surface of the deformable prism 41 and passes through the prism, the slow axis diameter D1 of the beam spot is magnified to D2, where D1 < D2. The magnification ratio is the cosine ratio of the refraction angle θ2 to the incident angle θ1. The magnification ratio can also be called the beam expansion ratio M. M can be calculated using the formula below:

[0039] This can be understood as the beam-expanding ratio M of the deformable prism 41 being equal to the designed slow-axis beam-expanding ratio. In this embodiment of the invention, the deformable prism 41 expands the slow-axis diameter D1 of the collimated beam to D2, therefore M = D2 / D1. Thus, referring to... Figure 1 and Figure 2 The elliptical collimated beam after being combined by the beam combiner 3 is shaped into an approximately square or circular light spot by the deformable prism 41. In this way, the influence of the astigmatism characteristics of the chip 11 can be reduced and the beam quality of the output laser can be improved.

[0040] In other embodiments, the fast axis diameter D2 can be reduced to D1 by the deformable prism 41, which can also achieve spot shaping of the collimated beam to achieve an approximately square or circular spot output. The embodiments of this utility model will not be explained in detail here.

[0041] It should be noted that, in this embodiment of the invention, the deformable prism 41 can be used to change the beam diameter along the fast or slow axis of the collimated beam, while maintaining the optical axis of the collimated beam unchanged and propagating along the other axis, thereby expanding the beam size and reshaping the beam. The characteristics of the deformable prism 41 can be used to correct the asymmetric elliptical beam generated by the chip 11, obtaining a nearly circular (or square) laser spot, which facilitates subsequent fiber coupling or beam splitting.

[0042] refer to Figure 1 The focusing lens 42 can be an aspherical lens. In this embodiment, a deformable prism 41 is used to shape the collimated beam spot. Since the deformable prism 41 has shaped the collimated beam from an elliptical beam into a circular beam, only one focusing lens 42 is needed at the rear end of the shaped collimated beam to focus it in the fast axis direction, thus achieving single-beam output. Compared to the prior art, which requires setting a fast-axis collimating lens and a slow-axis collimating lens after the beam combiner 3, this application eliminates the need for a slow-axis focusing lens at the rear end of the beam combiner 3, reducing production costs. Furthermore, the semiconductor laser device provided by this embodiment has the advantages of a short working length and a compact output optical path structure.

[0043] It should be noted that in optical structures based on conventional focusing modules, the conventional slow-axis focusing lens is typically a spherical cylindrical lens, but it can also be an aspherical cylindrical lens. In the field of high-power lasers, spherical lenses are limited by high power, resulting in limited choices and focal lengths, and are more expensive compared to flat glass processing. However, in the semiconductor laser device provided in this embodiment, the deformable prism 41 has a large angular tolerance and low surface precision requirements, which can reduce the cost of the lens to a certain extent.

[0044] Optionally, the semiconductor laser device of this application further includes a half-wave plate (not shown in the figure), which is disposed in the output optical path between the first spot steering element 51 and the polarization combiner. The half-wave plate can also be called a phase retardation plate or a half-wave plate. It is made of a birefringent material. Using a half-wave plate can change the polarization direction of linearly polarized light, for example, converting vertically polarized light into horizontally polarized light. In some embodiments, the polarization directions of the first collimated beam and the second collimated beam are not orthogonal. By adding a half-wave plate, the polarization direction of the second collimated beam can be adjusted so that the polarization directions of the second collimated beam and the first collimated beam are orthogonal.

[0045] Based on the above embodiments, refer to Figure 1 The semiconductor laser device also includes a housing substrate 6, on which the chip assembly 1 is disposed. The housing substrate 6 is used to support and encapsulate the various components of the semiconductor laser device. In this embodiment, each chip assembly 1 includes multiple chips 11. According to the number of chips 11 in the chip assembly 1, a stepped structure is set at the position of the housing substrate 6 corresponding to each chip assembly 1. A group of chips 11 is placed on each stepped structure, and the light emission centers of multiple chips 11 in the same path are all on different planes. After several chips 11 are collimated by the collimating assembly 2, they are reflected by their corresponding first spot turning element 51. The multiple collimated beams are stacked in the fast axis direction to the beam combining assembly 3. After being combined by the beam combining assembly 3, they are shaped and output by the shaping assembly 4. This arrangement is beneficial for the coaxiality of multiple pump beams and improves the laser coupling efficiency.

[0046] Along the direction away from the beam-combining component 3, the height of the stepped structure increases sequentially, and the light-emitting centers of two adjacent chips 11 become higher sequentially.

[0047] Based on the above embodiments, please continue to refer to Figure 1 The semiconductor laser device also includes a second beam steering element 52, which is disposed in the light output direction of the deformable prism 41. This second beam steering element 52 is used to adjust the output direction of the collimated beam output from the deformable prism 41, reducing the length of the semiconductor laser device along the first direction, which is beneficial for overall integration and miniaturization. The second beam steering element 52 can be a coated mirror.

[0048] For example, the second beam deflection element 52 is disposed in the output light path between the deformable prism 41 and the focusing lens 42, and is used to deflect the collimated beam after being shaped by the deformable prism 41 to the focusing lens 42.

[0049] The first beam steering element 51 and the second beam steering element 52 are both perpendicular to the housing substrate 6 to ensure that the laser output beam can be emitted in a horizontal direction during normal use.

[0050] refer to Figure 1The shaping component 4 may also include a fixing member 45, through which the deforming prism 41 is fixed to the surface of the housing substrate.

[0051] In this embodiment of the invention, the number of chip components can be reasonably selected according to the output power. Each group of chip components emits one pump light. Multiple pump lights are output after beam shaping by collimation component, beam combining component, spot shaping, focusing coupling or beam splitting, so as to achieve high power and high brightness laser output.

[0052] It should be noted that the semiconductor laser device also includes an electrical module (not shown in the figure). The electrical module is electrically connected to the pump light module. The electrical module includes a control circuit. The chip assembly is electrically connected to the control circuit. The control circuit is configured to control the driving current of the light-emitting component to adjust the power value of the pump light and stabilize the laser power of the collimated beam.

[0053] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, combinations, and substitutions can be made without departing from the protection scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments. Many other equivalent embodiments may be included without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A semiconductor laser device, characterized by comprising: The application relates to a pump light module and a shaping assembly. The pump light module is used for outputting a collimated light beam. The shaping assembly is arranged on the output light path of the collimated light beam, and comprises a deformation prism and a focusing mirror arranged in sequence. The deformation prism is used for correcting the collimated light beam so that the sizes of the light spot of the collimated light beam in the fast-axis direction and the slow-axis direction are consistent.

2. The semiconductor laser device according to claim 1, characterized by The focusing mirror is used for focusing the collimated light beam corrected by the deformation prism.

3. The semiconductor laser device according to claim 1, characterized by The application further comprises a coupling optical fiber.

4. The semiconductor laser device according to claim 1, characterized by The collimated light beam shaped by the shaping assembly is coupled into the coupling optical fiber and outputted.

5. The semiconductor laser device according to claim 1, characterized by The deformation prism is a right-angle prism.

6. The semiconductor laser device according to claim 5, characterized in that, The collimated light beam is incident from the right-angle surface or the inclined surface of the right-angle prism.

7. The semiconductor laser device of claim 1, wherein The refractive index of the deformation prism is greater than or equal to 1.45, and the transmittance is greater than 95%. The pump light module and the shaping assembly are arranged on the housing substrate.

8. The semiconductor laser device according to claim 7, characterized in that The shaping assembly further comprises a fixing member.

9. The semiconductor laser device of claim 8, wherein The deformation prism is fixed to the surface of the housing substrate through the fixing member. The pump light module comprises a beam combining assembly, at least one chip assembly and a plurality of collimating assemblies corresponding to the chips in the chip assembly. The collimating assemblies are used for converting the pump light emitted from the corresponding chips into collimated light beams.

10. The semiconductor laser device of claim 1, wherein The beam combining assembly is arranged on the output light path of at least two collimated light beams and is used for combining a plurality of collimated light beams into a single collimated light beam. The beam combining assembly comprises a polarization beam combiner and a plurality of first light spot turning elements. Each first light spot turning element is used for turning the collimated light beam emitted from the collimating assembly to the polarization beam combiner. The at least one chip assembly comprises a first chip assembly and a second chip assembly. The first pump light emitted from the first chip assembly is converted into a first collimated light beam by the collimating assembly. The second pump light emitted from the second chip assembly is converted into a second collimated light beam by the collimating assembly. The first collimated light beam is turned by the first light spot turning element and then reflected by the polarization beam combiner and outputted in a first direction. The second collimated light beam is turned by the first light spot turning element and then transmitted through the polarization beam combiner and outputted in the first direction. The application further comprises a second light spot turning element arranged on the light output direction of the deformation prism and used for adjusting the output direction of the collimated light beam outputted from the deformation prism.

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