Laser assembly, solid-state laser and laser processing equipment

Abstract

The utility model relates to the technical field of laser equipment, in particular to a laser assembly, a solid-state laser and laser processing equipment, and the laser assembly comprises a birefringent crystal which is used for emitting solid-state laser under the pumping effect, and the solid-state laser comprises two pieces of orthogonal polarized light with different wavelengths; the Q switch is arranged at one end of the birefringent crystal and is used for controlling the output of the solid-state laser; and the dual-wavelength output coupler is arranged at one end, deviating from the birefringent crystal, of the Q switch and is used for coupling and outputting two orthogonal polarized lights in the solid-state laser. Through the mode, the energy loss in the laser pumping cavity can be reduced, so that the laser threshold value is reduced, and the laser output power is improved.

Description

Technical Field

[0001] This application relates to the field of laser equipment technology, specifically to a laser component, a solid-state laser, and laser processing equipment. Background Technology

[0002] In the field of solid-state lasers, the most widely used host material is the uniaxial host crystal, such as YLiYF4 (lithium yttrium fluoride), GdVO4 (gadolinium vanadate), YVO4 (yttrium vanadate), etc. After pumping, the uniaxial host crystal will generate two orthogonally polarized lights with similar but different wavelengths.

[0003] Because these two polarized beams have very similar emission cross-sections on the uniaxial host crystal, they compete with each other during emission, leading to unstable laser output. To mitigate this effect, a etalon is typically inserted into the pump cavity of existing lasers. This etalon is used to select one polarized beam for output, filtering out the other, thereby eliminating the competition between the two polarized beams during emission.

[0004] Because the etalon filters out one polarized beam, this beam cannot be used, which inevitably increases the energy loss in the pump cavity, leading to an increase in the laser threshold and a decrease in output power. Utility Model Content

[0005] In view of the above problems, embodiments of this application provide a laser component, a solid-state laser, and a laser processing device, which can reduce energy loss in the laser pump cavity, thereby reducing the laser threshold and increasing the laser output power.

[0006] According to one aspect of the embodiments of this application, a laser assembly is provided, comprising: a birefringent crystal for emitting a solid-state laser under pumping action, the solid-state laser comprising two orthogonally polarized beams of different wavelengths; a Q-switch disposed at one end of the birefringent crystal for controlling the output of the solid-state laser; and a dual-wavelength output coupler disposed at the end of the Q-switch away from the birefringent crystal for coupling and outputting the two orthogonally polarized beams in the solid-state laser.

[0007] By incorporating a dual-wavelength output coupler into the laser assembly, the performance of the coupler is utilized to optimize the two polarized beams, minimizing their competition. The output laser's emission cross-section is the sum of the emission cross-sections of the σ-polarized and π-polarized beams. This achieves increased output power and stable quality without increasing design costs. Furthermore, although the two output polarized beams have different wavelengths, their wavelengths are similar. In many applications, especially those requiring extremely high laser power, small wavelength variations (e.g., a few nanometers to tens of nanometers) are not sensitive. Since the optical indices of optical materials do not change significantly with small wavelength variations, these variations do not affect beam transmission, shaping, collimation, or focusing, thus preserving laser performance. Specific applications include, but are not limited to, material scribing, cutting, drilling, annealing, and wafer lift-off.

[0008] In one alternative embodiment, the laser assembly further includes a dual-wavelength mirror positioned at the end of the birefringent crystal away from the Q-switch. The dual-wavelength mirror is used to reflect solid-state laser light arriving thereon back onto the birefringent crystal to adequately pump the birefringent crystal, thereby increasing the power of the final output solid-state laser.

[0009] In one alternative approach, the dual-wavelength reflector is a dual-wavelength high-reflectivity mirror, which typically has a reflectivity of over 99% for lasers of a specific wavelength. This allows the solid-state laser generated by the birefringent crystal to be fully utilized, thereby reducing the loss of laser energy in the pump cavity of the laser assembly and increasing the output power of the laser.

[0010] In one alternative embodiment, the laser assembly includes a first pump cavity and a second pump cavity, both of which are equipped with a birefringent crystal, a dual-wavelength mirror, a Q-switch, and a dual-wavelength output coupler in the same manner. The birefringent crystal in the first pump cavity is rotated 90° relative to the birefringent crystal in the second pump cavity, such that the solid-state laser output from the first pump cavity includes σ-polarized light of a first wavelength and π-polarized light of a second wavelength, and the solid-state laser output from the second pump cavity includes π-polarized light of the first wavelength and σ-polarized light of the second wavelength. The laser assembly also includes an optical processing module disposed in the output optical path of the first and second pump cavities. The optical processing module is used to combine the σ-polarized light of the first wavelength and the π-polarized light of the first wavelength into a first laser beam, and to combine the π-polarized light of the second wavelength and the σ-polarized light of the second wavelength into a second laser beam before outputting it.

[0011] In this embodiment, using the same first and second pump cavities, the birefringent crystals in the first and second pump cavities are rotated 90° relative to each other, so that the polarization directions of the two lasers of the same wavelength output from the first and second pump cavities are perpendicular to each other. Then, an optical processing module is used to combine the lasers of the same wavelength and perpendicular polarization direction and output them, thereby eliminating the polarization of the output laser and further improving the laser output power.

[0012] In one alternative embodiment, the optical processing module includes a mirror group, a polarization beam combiner, and a wavelength division multiplexer; the mirror group is used to adjust the propagation direction of the solid-state laser output from the first pump cavity and / or the second pump cavity; the polarization beam combiner is used to combine σ-polarized light of a first wavelength with π-polarized light of a first wavelength into a first laser beam and to combine π-polarized light of a second wavelength with σ-polarized light of a second wavelength into a second laser beam; the wavelength division multiplexer is used to multiplex the first laser beam and the second laser beam and output them.

[0013] By setting polarization beam combiners in the output optical paths of the first and second pump cavities, polarized light of the same wavelength and with perpendicular polarization directions can be combined, thereby eliminating the polarization of the output laser. Furthermore, by setting wavelength division multiplexers, the first and second lasers of different wavelengths obtained after beam combining can be transmitted synchronously without interference, thereby increasing transmission capacity and saving transmission resources.

[0014] In one alternative embodiment, the output ends of both the first and second pump cavities face a first direction; the mirror assembly includes a first reflector, a second reflector, and a third reflector; a polarization beam combiner is disposed at the output end of the first pump cavity to receive the solid-state laser output from the first pump cavity; the first reflector is disposed at the output end of the second pump cavity and is used to reflect the solid-state laser output from the second pump cavity in a second direction to the polarization beam combiner, wherein the second direction is perpendicular to the first direction; a wavelength division multiplexer is disposed on the side of the polarization beam combiner facing the first direction to receive the first laser beam propagating in the first direction after being combined by the polarization beam combiner; the second reflector is disposed on the side of the polarization beam combiner facing the second direction, and the third reflector is disposed on the side of the second reflector facing the first direction, and the third reflector is located on the side of the wavelength division multiplexer facing the second direction, wherein the second and third reflectors together are used to reflect the second laser beam propagating in the second direction after being combined by the polarization beam combiner to the wavelength division multiplexer.

[0015] In one alternative embodiment, the birefringent crystal is any one of lithium yttrium fluoride crystal, gadolinium vanadate crystal, yttrium vanadate crystal, or potassium gadolinium tungstate crystal.

[0016] In one alternative, the birefringent crystal is a neodymium-doped lithium yttrium fluoride crystal or a potassium ytterbium tungstate-doped crystal.

[0017] According to another aspect of the embodiments of this application, a solid-state laser is provided, including a pump source and a laser assembly as described in any of the above claims. The pump source is disposed on the side of a birefringent crystal and is used to emit laser light toward the birefringent crystal to pump the birefringent crystal.

[0018] The solid-state laser provided in this application reduces energy loss in the pump cavity and lowers the laser threshold by using the laser components provided in the above embodiments, thereby increasing the laser output power without increasing the design cost.

[0019] According to another aspect of the embodiments of this application, a laser processing apparatus is provided, including the above-described solid-state laser.

[0020] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0021] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0022] Figure 1 This is a schematic diagram of the structure of a Q-switched laser in the prior art;

[0023] Figure 2 This is a schematic diagram of the structure of the laser assembly provided in the embodiments of this application;

[0024] Figure 3 A simplified energy level diagram of Nd:YLF crystal;

[0025] Figure 4 The emission spectra of Nd:YLF crystal in σ-polarization and π-polarization are shown.

[0026] Figure 5a The spectrum of the output laser from the Nd:YLF crystal under a pump power of 2.07W is shown.

[0027] Figure 5b The spectrum of the output laser from the Nd:YLF crystal under a pump power of 5.77W is shown.

[0028] Figure 6The graph shows the relationship between the output power of 1047nm (σ-polarized) light, the output power of 1053nm (π-polarized) light, and the bus output power of both light sources and the pump light absorption.

[0029] Figure 7 The absorption spectrum of Yb:KGW crystal is shown below.

[0030] Figure 8 Laser spectra of Yb:KGW crystals under different pump powers;

[0031] Figure 9a , Figure 9b and Figure 9c The graphs show the relationship between the output power of different polarization modes and the total output power versus the pump power when using dual-wavelength output couplers 130 with transmittance of 1.6%, 3%, and 5%.

[0032] Figure 10 This is a schematic diagram of the structure of a laser assembly provided in another embodiment of this application;

[0033] Figure 11 This is a schematic diagram of the structure of a solid-state laser provided in an embodiment of this application.

[0034] The reference numerals in the detailed embodiments are as follows:

[0035] 11. Rear reflector; 12. Erection datum; 13. Gain dielectric; 14. Q-switch; 15. Output coupler;

[0036] 100. Laser assembly; 110. Birefringent crystal; 120. Q-switch; 130. Dual-wavelength output coupler; 140. Dual-wavelength mirror;

[0037] 101. First pump chamber; 102. Second pump chamber;

[0038] 103. Optical processing module; 1031. Mirror group; 1031a. First reflecting mirror; 1031b. Second reflecting mirror; 1031c. Third reflecting mirror; 1032. Polarizing beam combiner; 1033. Wavelength division multiplexer;

[0039] 200, pump source; 500, solid-state laser. Detailed Implementation

[0040] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0042] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0043] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0044] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent three cases: A exists, A and B exist simultaneously, and B exists. In addition, the character " / " in this document generally indicates that the related objects before and after are in an "or" relationship.

[0045] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0046] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0047] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0048] In existing technologies, a typical approach to selecting one polarized beam output using an etalon is a Q-switched laser, as shown in the example below. Figure 1 As shown, the pump cavity of the laser includes a back reflector 11, an etalon 12, a gain medium 13, a Q-switch 14, and an output coupler 15. A pump source, not shown in the figure, is also present in the pump cavity. The gain medium 13 is a birefringent crystal. The pump source excites the gain medium 13 by emitting pump light towards it to generate two polarized lights with similar wavelengths. The back reflector 11 reflects the laser light reaching it back onto the gain medium 13. The etalon 12 can be a glass plate with two parallel surfaces. When the laser light generated by the gain medium 13 passes through the etalon 12 and is reflected from its surface, the reflected and transmitted light interfere with each other, forming periodic peaks. When the etalon 12 is tilted, these peaks shift within the wavelength (frequency) threshold. When one wavelength of polarized light coincides with the peak, that wavelength of polarized light is output preferentially over the other wavelength, thus achieving selection of one of the polarized lights. Figure 1 In the specific example shown, the final output from the output coupler 15 is only π-polarized laser (i.e., the polarization direction is as shown by the P-axis in the figure).

[0049] Although the Q-switched laser provided above can achieve selective output of one polarized light through the etalon 12, thereby reducing the competition between the two polarized lights during the emission process, it will cause energy loss because it will filter out one polarized light, resulting in an increase in the laser threshold of the pump cavity and a decrease in output power.

[0050] In order to increase the output power of the laser without increasing the cost of the laser, this application considers mitigating the competition between the two polarized lights without filtering one of them, so as to ensure that both polarized lights can be output, thereby reducing the laser threshold and increasing the output power.

[0051] According to one aspect of an embodiment of this application, a laser assembly is provided, as detailed in the following reference. Figure 2The figure shows the structure of a laser assembly provided in an embodiment of this application. The laser assembly 100 includes a birefringent crystal 110, a Q switch 120, and a dual-wavelength output coupler 130.

[0052] The birefringent crystal 110 can be a uniaxial crystal, such as YLiF4 (lithium yttrium fluoride crystal, abbreviated as YLF), GdVO4 (gadolinium vanadate crystal) or YVO4 (yttrium vanadate crystal), or it can be a biaxial crystal, such as KGW (potassium gadolinium tungstate crystal), preferably Nd:YLF (neodymium-doped lithium yttrium fluoride crystal) or Yb:KGW (ytterbium-doped potassium gadolinium tungstate crystal).

[0053] The birefringent crystal 110 is used to emit solid-state laser light under pumping, which comprises two orthogonally polarized beams of different wavelengths. For an example using Nd:YLF, please refer to [link to relevant documentation]. Figure 3 The figure shows the energy level of the Nd:YLF crystal. Two sets of emission lines are visible: one set includes wavelengths of 1313 nm (σ-polarized) and 1321 nm (π-polarized), and the other set includes wavelengths of 1053 nm (σ-polarized) and 1047 nm (π-polarized). Therefore, when the Nd:YLF crystal is pumped, it will produce two orthogonally polarized beams: one at 1313 nm (σ-polarized) and the other at 1321 nm (π-polarized), or one at 1053 nm (σ-polarized) and the other at 1047 nm (π-polarized).

[0054] A Q-switch 120 is located at one end of a birefringent crystal 110 and is used to control the output of a solid-state laser. Specifically, a Q-switch is an active or passive modulation technique for lasers that generates high-power, short-pulse laser output by controlling the quality factor (Q value) of the pump cavity. This technique is widely used in the field of high peak power pulsed lasers, such as laser processing, medical applications, ranging, and scientific research.

[0055] A dual-wavelength output coupler 130 is positioned at the end of the Q-switch 120 away from the birefringent crystal 110, and is used to couple and output two orthogonally polarized beams from a solid-state laser. For example... Figure 2 As shown, two orthogonally polarized lights are coupled and output through a dual-wavelength output coupler 130, so that the final output laser contains both π-polarized light (polarization direction is shown in the P-axis direction) and σ-polarized light (polarization direction is shown in the S-axis direction).

[0056] In this embodiment, by setting a dual-wavelength output coupler 130 in the laser assembly 100, the performance of the dual-wavelength output coupler 130 is used to optimize the two polarized lights, so that the competition between them is eliminated as much as possible. The emission cross section of the output laser is the sum of the emission cross section of σ-polarized light and π-polarized light. Thus, the output power of the laser is increased and the quality is stabilized without increasing the design cost.

[0057] Furthermore, although the two output polarized lights have different wavelengths, their wavelengths are similar. In many applications, especially those requiring extremely high laser power, small changes in wavelength (e.g., from a few nanometers to tens of nanometers) are not sensitive. Since the optical indices of optical materials do not change significantly with small wavelength variations, these small changes will not affect beam transmission, shaping, collimation, or focusing, and therefore the laser performance will not be affected. Specific applications include, but are not limited to, material scribing, cutting, drilling, annealing, and wafer lift-off.

[0058] To further reduce energy loss in the pump cavity of the laser assembly 100 and lower the laser threshold, as shown in Figure 5, the laser assembly 100 may also include a dual-wavelength mirror 140. The dual-wavelength mirror 140 is disposed at the end of the birefringent crystal 110 away from the Q switch 120. The dual-wavelength mirror 140 is used to reflect the solid-state laser (containing two polarized lights) emitted from and reaching the birefringent crystal 110 back to the birefringent crystal 110 to fully pump the birefringent crystal 110, thereby increasing the power of the final output solid-state laser.

[0059] To improve the reflectivity of the dual-wavelength reflector 140, the dual-wavelength reflector 140 is preferably a dual-wavelength high reflectivity mirror. For lasers of a specific wavelength, the reflectivity of the dual-wavelength high reflectivity mirror can usually reach more than 99%, which allows the solid-state laser generated by the birefringent crystal 110 to be fully utilized, thereby reducing the loss of laser energy in the pump cavity of the laser assembly 100 and improving the output power of the laser.

[0060] exist Figure 2 Based on the illustrated embodiment, the birefringent crystal 110 is a C-cut Nd:YLF crystal, and when pumped by an 806nm wavelength laser, as shown... Figure 4 The emission spectra of the Nd:YLF crystal in π-polarization and σ-polarization are shown. Because the generated σ-polarized light and π-polarized light have different spectral characteristics, there is still a certain degree of competition between them, resulting in unstable output power for each polarized light beam. Furthermore, the output power of each polarized light beam changes with varying operating conditions. Specifically... Figure 5a and Figure 5b As shown, Figure 5a and Figure 5bThe spectrum of laser light generated by an Nd:YLF crystal under different operating conditions (the figure shows examples with different pump powers), as shown below. Figure 5a As shown, at pump power P in Under the condition of 2.07W, the total output power P of the two polarized lights is... out，total =0.34W, and the power of light with a wavelength of 1047nm (σ-polarized) is much greater than the power of light with a wavelength of 1053nm (π-polarized). At pump power P in Under the condition of 5.77W, the total output power P of the two polarized lights is out，total =1.25W, and the output of the two polarized lights becomes that the power of the 1047nm (σ-polarized) laser is slightly less than the power of the 1053nm (π-polarized) laser.

[0061] Although the power of the two polarized beams will vary under different operating conditions, please refer to [link / reference needed]. Figure 6 As the birefringent crystal 110 absorbs the pump light, the output power of the 1047nm (σ-polarized) light and the 1053nm (π-polarized) light generated by the birefringent crystal 110 will change unstablely. However, their total output power remains stable. It can be seen that the laser assembly 100 provided in this application embodiment can output high-power and stable solid-state laser.

[0062] exist Figure 2 Based on the illustrated embodiment, the birefringent crystal 110 can also be a Yb:KGW crystal, where the three mutually perpendicular crystal axes of the Yb:KGW crystal are Nm, Np, and Ng, respectively. For example... Figure 7 The absorption spectrum of the Yb:KGW crystal shows that at a pump wavelength near 980 nm, the absorption cross-sections in the three polarization directions (E / / Nm parallel to the Nm axis, E / / Np parallel to the Np axis, and E / / Ng parallel to the Ng axis) are all different. This results in polarization being highly dependent on the pump absorption and laser emission cross-sections. Since the Yb:KGW crystal is cut to propagate the beam along the Nm axis (i.e., Nm cut), the Np and Ng axes can be considered as the primary side pump directions.

[0063] like Figure 8 The laser spectra of Yb:KGW crystals under different pump powers are shown. Taking a dual-wavelength output coupler 130 with a transmittance of 3% and a Yb:KGW crystal doping concentration of 1.5 atomic percentages as an example, the Yb:KGW crystal mainly has two emission wavelengths: the Nm polarization mode emission wavelength is λm = 1028.5 nm, and the Np polarization mode emission wavelength is λp = 1037.7 nm. Under low pump power conditions, such as... Figure 8The spectra corresponding to pump powers of 14.3 W and 17.1 W show that the gain gp(λp) of the Np polarization mode is higher than the gain gm(λm) of the Nm polarization mode. However, this dynamic relationship changes at high pump powers. For example, when the pump power is 18.6 W, gm(λm) is greater than gp(λp), while when the pump power is 24.7 W and 26.8 W, gp(λp) becomes greater than gm(λm).

[0064] Please refer to further information. Figure 9a , Figure 9b and Figure 9c , Figures 9a to 9c The figures show the variations in output power of the Nm and Np polarization modes, as well as their total output power (corresponding to the "Total" curve in the figure), as a function of pump power when using dual-wavelength output couplers 130 with transmittances of 1.6%, 3%, and 5%. As shown, although the output power of the Nm and Np polarization modes exhibits unstable dynamic changes with varying pump power, their total output power maintains a stable trend, thus ensuring a stable high-power laser output from the laser assembly.

[0065] Furthermore, this application also proposes an implementation method that can remove the polarization of the final output solid-state laser, while also further increasing the laser output power. For details, please refer to [link to relevant documentation]. Figure 10 The figure shows a schematic structure of a laser assembly 100 provided in another embodiment. As shown, the laser assembly 100 includes a first pump cavity 101 and a second pump cavity 102. Both the first pump cavity 101 and the second pump cavity 102 are equipped with a birefringent crystal 110, a Q-switch 120, a dual-wavelength mirror 140, and a dual-wavelength output coupler 130 in the same manner. The birefringent crystal 110 in the first pump cavity 101 is rotated 90° relative to the birefringent crystal in the second pump cavity 102, so that the solid-state laser output from the first pump cavity 101 includes σ-polarized light of a first wavelength λ1 (polarization direction parallel to the P-axis, denoted as P in the figure). λ1 The first wavelength (λ) represents the polarized light, and the second wavelength (λ2) represents the π-polarized light (the polarization direction is parallel to the S-axis, as shown in the figure). λ2 The solid-state laser output from the second pump cavity 102 includes π-polarized light with a first wavelength λ1 (represented by S in the figure). λ1 (represented by) and the second wavelength λ2 σ-polarized light (this polarized light is represented by P in the figure) λ2 express).

[0066] The laser assembly 100 also includes an optical processing module 103, which is disposed in the output optical path of the first pump cavity 101 and the second pump cavity 102. The optical processing module 103 is used to process the polarized light P λ1 With Sλ1 Merged into a single first laser PS λ1 And polarized light P λ2 With S λ2 Merged into a second laser PS λ2 Output later.

[0067] Specifically, the optical processing module 103 can be implemented by selecting appropriate combinations of optical components. The specific combination method is not limited here, as long as it can combine two lasers with the same wavelength and perpendicular polarization direction into one beam and output it.

[0068] In this embodiment, using the same first pump cavity 101 and second pump cavity 102, the birefringent crystals 110 in the first pump cavity 101 and second pump cavity 102 are rotated 90° relative to each other, so that the two lasers of the same wavelength output from the first pump cavity 101 and the second pump cavity 102 have polarization directions perpendicular to each other. Then, by setting up an optical processing module 103, the lasers of the same wavelength and perpendicular polarization directions are combined and output, thereby eliminating the polarization of the output laser and further improving the laser output power.

[0069] For the light processing module 103, this application further proposes a specific implementation scheme, such as... Figure 10 As shown, the optical processing module 103 may include a mirror group 1031, a polarization beam combiner 1032, and a wavelength division multiplexer 1033. The mirror group 1031 is used to adjust the propagation direction of solid-state laser output from at least one of the first pump cavity 101 and the second pump cavity 102. The polarization beam combiner 1032 is used to combine the polarized light P... λ1 With S λ1 Merged into a single first laser PS λ1 Polarized light P λ2 With S λ2 Merged into a second laser PS λ2 The wavelength division multiplexer 1033 is used to convert the first laser PS λ1 Second laser PS λ2 Reuse and output.

[0070] By setting a polarization beam combiner 1032 in the output optical path of the first pump cavity 101 and the second pump cavity 102, the beam combining of polarized light with the same wavelength and perpendicular polarization direction is realized, thereby eliminating the polarization of the output laser. By setting a wavelength division multiplexer 1033, the first laser and the second laser with different wavelengths obtained after beam combining can be transmitted synchronously without interference, thereby improving the transmission capacity and saving the resources required for transmission.

[0071] Please refer to it again. Figure 10The figure also provides a specific optical path design scheme. As shown, the output ends of the first pump cavity 101 and the second pump cavity 102 both face the first direction (the direction indicated by the dashed arrow M in the figure). The mirror group 1031 includes a first reflecting mirror 1031a, a second reflecting mirror 1031b, and a third reflecting mirror 1031c. The polarization beam combiner 1032 is disposed at the output end of the first pump cavity 101 to receive the solid-state laser (including polarized P) output by the first pump cavity 101. λ1 and S λ2 The first reflector 1031a is disposed at the output end of the second pump cavity 102. The first reflector 1031a is used to reflect the solid-state laser (including polarized light P) output from the second pump cavity 102. λ2 and S λ1 The light is reflected in the second direction (as indicated by the dashed arrow N in the figure) onto the polarizing beam combiner 1032.

[0072] A wavelength division multiplexer 1033 is positioned on the side of the polarization beam combiner 1032 facing the direction indicated by arrow M, to receive the first laser PS propagating in the direction indicated by arrow M after being combined by the polarization beam combiner 1032. λ1 The second reflector 1031b is positioned on the side of the polarization beam combiner 1032 facing the direction indicated by arrow N, and the third reflector 1031c is positioned on the side of the second reflector 1031b facing the direction indicated by arrow M, and the third reflector 1031c is located on the side of the wavelength division multiplexer 1033 facing the direction indicated by arrow N. The second reflector 1031b and the third reflector 1031c together are used to combine the second laser PS, which propagates in the direction indicated by arrow N after being combined by the polarization beam combiner 1032. λ2 Reflected to wavelength division multiplexer 1033.

[0073] It should be noted that, Figure 10 This is merely an exemplary illustration of the configuration of the output optical path of the first pump cavity 101 and the second pump cavity 102 and the optical processing module 103 in this application. Based on the concept proposed in this application, various configuration methods can be easily designed in other implementations, which will not be elaborated here.

[0074] According to another aspect of the embodiments of this application, a solid-state laser is provided, as detailed in [reference needed]. Figure 11 The figure shows the structure of a solid-state laser. As shown in the figure, the solid-state laser 500 includes a pump source 200 (e.g., a laser diode) and a laser assembly 100 as described in any of the above embodiments. The pump source 200 can be one or multiple as shown in the figure. The pump source 200 is disposed on the side of the birefringent crystal 110 and is used to emit laser light toward the birefringent crystal 110 to pump the birefringent crystal 110.

[0075] The solid-state laser 500 provided in this application embodiment reduces energy loss in the pump cavity and lowers the laser threshold by adopting the laser component 100 provided in the above embodiment, thereby increasing the laser output power without increasing the design cost.

[0076] According to another aspect of the embodiments of this application, a laser processing apparatus is provided, which includes the solid-state laser 500 in the above embodiments.

[0077] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way.

Claims

1. A laser assembly, characterized by, The laser assembly comprises: a birefringent crystal for emitting a solid-state laser under pumping, the solid-state laser comprising two orthogonally polarized lights of different wavelengths; a Q-switch arranged at one end of the birefringent crystal for controlling the output of the solid-state laser; and a dual-wavelength output coupler arranged at the end of the Q-switch away from the birefringent crystal for coupling and outputting the two orthogonally polarized lights in the solid-state laser.

2. The laser assembly of claim 1, wherein, The laser assembly further comprises a dual-wavelength reflector arranged at the end of the birefringent crystal away from the Q-switch for reflecting the solid-state laser arriving thereon back to the birefringent crystal.

3. The laser assembly of claim 2, wherein, The dual-wavelength reflector is a dual-wavelength high reflector.

4. The laser assembly of claim 2, wherein, The laser assembly comprises a first pumping cavity and a second pumping cavity, and the birefringent crystal, the dual-wavelength reflector, the Q-switch and the dual-wavelength output coupler are arranged in the same way in the first pumping cavity and the second pumping cavity. The birefringent crystal in the first pumping cavity is rotated by 90° relative to the birefringent crystal in the second pumping cavity, so that the solid-state laser output by the first pumping cavity comprises σ-polarized light of a first wavelength and π-polarized light of a second wavelength, and the solid-state laser output by the second pumping cavity comprises π-polarized light of the first wavelength and σ-polarized light of the second wavelength. The laser assembly further comprises an optical processing module arranged in the output light path of the first pumping cavity and the second pumping cavity, the optical processing module being used for merging the σ-polarized light of the first wavelength and the π-polarized light of the first wavelength into a first laser and merging the π-polarized light of the second wavelength and the σ-polarized light of the second wavelength into a second laser.

5. The laser assembly of claim 4, wherein, The optical processing module comprises a mirror group, a polarized light combiner and a wavelength division multiplexer. The mirror group is used for adjusting the propagation direction of the solid-state laser output by the first pumping cavity and / or the second pumping cavity. The polarized light combiner is used for merging the σ-polarized light of the first wavelength and the π-polarized light of the first wavelength into a first laser and merging the π-polarized light of the second wavelength and the σ-polarized light of the second wavelength into a second laser. The wavelength division multiplexer is used for multiplexing and outputting the first laser and the second laser.

6. The laser assembly of claim 5, wherein, The output ends of the first pumping cavity and the second pumping cavity are both directed in a first direction. The mirror group comprises a first mirror, a second mirror and a third mirror. The polarized light combiner is arranged at the output end of the first pumping cavity to receive the solid-state laser output by the first pumping cavity. The first mirror is arranged at the output end of the second pumping cavity, and is used for reflecting the solid-state laser output by the second pumping cavity to the polarized light combiner in a second direction perpendicular to the first direction. The wavelength division multiplexer is arranged at the side of the polarized light combiner facing the first direction to receive the first laser propagating in the first direction after being merged by the polarized light combiner. The second mirror is arranged on one side of the polarization light combiner towards the second direction, the third mirror is arranged on one side of the second mirror towards the first direction, and the third mirror is arranged on one side of the wavelength division multiplexer towards the second direction, and the second mirror and the third mirror are used together to reflect the second laser propagating towards the second direction after being combined by the polarization light combiner to the wavelength division multiplexer.

7. The laser assembly of any of claims 1-6, wherein, The birefringent crystal is any one of yttrium lithium fluoride crystal, gadolinium vanadate crystal, yttrium vanadate crystal or potassium gadolinium tungstate crystal.

8. The laser assembly of claim 7, wherein, The birefringent crystal is neodymium-doped yttrium lithium fluoride crystal or ytterbium-doped potassium gadolinium tungstate crystal.

9. A solid state laser, characterized by The solid-state laser comprises a pump source arranged on the side of the birefringent crystal, and the pump source is used to emit laser towards the birefringent crystal to pump the birefringent crystal.

10. A laser processing apparatus characterized by comprising: The solid-state laser comprises the laser assembly of any one of claims 1-8. The solid-state laser comprises the laser assembly of any one of claims 1-8.

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