Pumping assembly and solid state laser

Abstract

The application relates to the technical field of laser devices, and discloses a pumping assembly and a solid-state laser. The pumping assembly comprises a gain medium rod and a plurality of pumping sources, and the plurality of pumping sources are arranged in an axial and circumferential array of the gain medium rod. The plurality of pumping sources are configured to emit light towards the gain medium rod, wherein the plurality of pumping sources arranged in the circumferential direction and towards the same cross section of the gain medium rod are arranged at intervals, and the plurality of pumping sources arranged in the axial direction and in the same line are also arranged at intervals. The plurality of pumping sources arranged in the circumferential direction and towards the same cross section of the gain medium rod form a group of pumping sources, and the projections of the adjacent two groups of pumping sources on the same plane in the axial direction are arranged at intervals. All the pumping sources are connected in series to form at least one power supply circuit, and the pumping sources are used for emitting light towards the gain medium rod when powered on, so as to excite the gain medium rod to output laser. In the above manner, the application can alleviate the heating problem of the gain medium rod and the pumping sources on the basis of ensuring that the output laser has good uniformity.

Description

Technical Field

[0001] This application relates to the field of laser device technology, specifically to a pump assembly and a solid-state laser. Background Technology

[0002] In solid-state laser applications, side pumping is an effective method for generating high-energy lasers. In existing methods, to improve the uniformity of the pump light received by the gain dielectric rod, multiple strip-shaped pump modules are usually distributed circumferentially along the gain dielectric rod, with multiple pump sources closely arranged axially on each pump module.

[0003] Distributing more pump modules circumferentially can improve the uniformity of pump light received by the gain dielectric rod to some extent, resulting in a more uniform population inversion and thus a more uniform laser beam output to meet the needs of more application scenarios. However, more pump modules will increase the intensity of pump light received by the gain dielectric rod, causing severe heating of the gain dielectric rod, which may trigger amplified spontaneous emission (ASE) and nonradiative relaxation processes. In worse cases, the uneven heat distribution on the cross-section of the gain dielectric rod may cause internal stress, leading to cracks in the gain dielectric rod.

[0004] In addition, the multiple pump sources arranged closely along the axial direction on the pump module will heat each other during operation, causing thermal crosstalk problems on the pump module, which will seriously affect the service life of the pump sources.

[0005] In summary, how to alleviate the heating problem of the gain medium rod and pump source while ensuring good uniformity of the output laser has become an urgent problem to be solved in current pumping technology. Summary of the Invention

[0006] In view of the above problems, embodiments of this application provide a pump component and a solid-state laser, which can alleviate the heating problems of the gain dielectric rod and the pump source while ensuring good uniformity of the output laser.

[0007] According to one aspect of the embodiments of this application, a pumping assembly is provided, comprising: a gain dielectric rod and a plurality of pump sources, wherein the plurality of pump sources are arranged in an axial and circumferential array along the gain dielectric rod; the plurality of pump sources are all configured to emit light toward the gain dielectric rod, wherein the plurality of pump sources arranged circumferentially and facing the same cross section of the gain dielectric rod are spaced apart from each other, and the plurality of pump sources collinear along the axial direction are also spaced apart from each other; the plurality of pump sources facing the same cross section of the gain dielectric rod constitute a group of pump sources, and the projections of two adjacent groups of pump sources on the same plane along the axial direction are staggered from each other; all the pump sources are connected in series to form at least one power supply line, and the pump sources are used to emit light toward the gain dielectric rod when energized to excite the gain dielectric rod to output laser.

[0008] Compared with conventional solutions, the embodiments provided in this application, while keeping the total number of pump sources and the number of pump directions unchanged, allow different sections of the cross-section of the gain dielectric rod to be effectively pumped from different angles. This enables the gain dielectric rod to be effectively pumped from more angles as a whole, resulting in a more uniform population inversion and thus a more uniform laser beam with a more uniform intensity distribution. Since the total number of pump sources and the number of pump directions remain unchanged, it is ensured that the pump power will not increase and the heating of the gain dielectric rod will not worsen.

[0009] Furthermore, since the multiple pump sources in this embodiment are arranged at intervals along both the circumferential and axial directions of the gain dielectric rod, the thermal crosstalk problem between the pump sources can be effectively alleviated, thereby extending the service life of the pump sources. If it is desired that the pump sources in this application have the same service life as those in conventional solutions, then compared to conventional solutions, the driving current of the pump sources can be increased to obtain more pump power, thereby increasing the power of the laser output from the gain dielectric rod.

[0010] In one alternative embodiment, the pump assembly includes multiple strip-shaped pump modules, each extending axially. Each pump module contains multiple pump sources arranged and fixed axially, with the pump sources in each module connected in series. This arrangement simplifies the structure of each pump module, facilitating its processing, manufacturing, and assembly, thereby reducing production costs.

[0011] In one alternative approach, multiple pump modules are arranged at equal intervals along the circumference. This arrangement ensures uniform pump intensity distribution on the gain dielectric rod while preventing interference between two opposing pump sources.

[0012] In one alternative approach, multiple pump sources on each pump module are arranged at equal intervals along the axial direction. This arrangement ensures that the portions of the gain medium bar pumped from the same angle have the same axial dimension.

[0013] In one alternative approach, within each pump module, the minimum distance between two adjacent pump sources along the axial direction is equal to the size of one pump source. This configuration ensures a continuous pump region is formed in the middle of the gain dielectric rod, thereby reducing energy loss in the pump assembly and enabling the gain dielectric rod to output a laser beam with higher power and more uniform intensity distribution.

[0014] In one alternative approach, a heat-conducting block is provided between two adjacent pump sources in each pump module to improve the heat dissipation efficiency of the pump sources.

[0015] In one optional embodiment, multiple pump modules are divided into a first module group and a second module group, with the first and second module groups containing an equal number of pump modules. The pump modules in the first module group have identical structures, and each pump module has a first gap. Similarly, the pump modules in the second module group have identical structures, and each pump module has a second gap. The pump modules in the first and second module groups are arranged circumferentially, such that the pump sources on the pump modules in the first module group are opposite to the second gaps on both sides of the circumferential direction, and the pump sources on the pump modules in the second module group are opposite to the first gaps on both sides of the circumferential direction. In this embodiment, the first module group consists of multiple structurally identical pump modules, and the second module group consists of multiple structurally identical pump modules, ensuring that the pump modules have at most two different structural forms. This facilitates mass production of the pump modules, thereby reducing the required manufacturing costs. Based on this, multiple pump modules in the first module group and multiple pump modules in the second module group are arranged circumferentially, with the pump sources on the pump modules in the first module group facing each other along the circumferential direction and the second gaps on the pump modules in the second module group. Conversely, the pump sources on the pump modules in the second module group face each other along the circumferential direction and the first gaps on the pump modules in the first module group. This allows different sections of the cross-section of the gain dielectric rod to be effectively pumped from different angles, resulting in a more uniform population inversion in the gain dielectric rod and thus a laser beam with a more uniform energy distribution.

[0016] In one alternative approach, the pump modules in the first module group have the same structure as those in the second module group. This arrangement allows for the assembly of pump assemblies by simply manufacturing identical pump modules in batches, simplifying the production process and reducing manufacturing costs.

[0017] In one alternative embodiment, a transparent flow tube is fitted onto the gain dielectric rod, through which coolant is introduced to dissipate heat and cool the gain dielectric rod, thereby improving the heat dissipation efficiency of the gain dielectric rod.

[0018] According to another aspect of the embodiments of this application, a solid-state laser is provided, including the pumping component of any of the above.

[0019] The solid-state laser provided in this application, by employing the aforementioned pumping components, can achieve more uniform population inversion with fewer pump directions, thereby outputting a laser beam with a more uniform energy distribution, reaching a more ideal state. Furthermore, because the pump sources are spaced apart, thermal crosstalk problems are mitigated, allowing each pump source to fully utilize its pump power, resulting in a relatively smaller number of required pump sources. In addition, based on the mitigation of thermal crosstalk between pump sources, if the pump sources are to maintain the same lifespan as in conventional solutions, the current driving the pump sources can be increased, thereby obtaining more pump power and laser output power while still ensuring the original lifespan of the 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 1a and Figure 1b These are, respectively, the existing 3-directional pumping scheme and the 5-directional pumping scheme;

[0023] Figure 2 A side view of a pump assembly in the prior art;

[0024] Figure 3a and Figure 3b These are, respectively, a side view and a top view of a pump module in the prior art;

[0025] Figure 4 An end view of the pump assembly provided in an embodiment of the present invention;

[0026] Figure 5 and Figure 6 They are respectively Figure 4 Side views of the pump assembly on opposite sides;

[0027] Figure 7 An end view of the pump assembly provided in an embodiment of the present invention;

[0028] Figure 8aA side view of the pump module in the first module group of the pump assembly provided in an embodiment of the present invention;

[0029] Figure 8b A side view of the pump module in the second module group of the pump assembly provided in an embodiment of the present invention;

[0030] Figure 9 A top view of a pump module with a heat-conducting block provided in an embodiment of the present invention;

[0031] Figure 10a and Figure 10b The images show the pump light power distribution along the gain dielectric rod axis from both the stereo view and the end-face view in the traditional scheme.

[0032] Figure 11 This is a top view of the pump module in the first module group and the second module group used in the embodiments of the present invention;

[0033] Figure 12a and Figure 12b These are, respectively, diagrams showing the pump light power distribution along the axial direction of the gain dielectric rod from a stereoscopic viewpoint and an end-face viewpoint in embodiments of the present invention.

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

[0035] 100 Pump assembly; 110 Gain medium rod; 120 Pump source; 130 Pump module; 131 First module group; 132 Second module group; 141 First gap; 142 Second gap; 150 Heat-conducting block; 160 Transparent flow tube; 170 Coolant. Detailed Implementation

[0036] 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.

[0037] 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.

[0038] 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.

[0039] 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.

[0040] 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 it have an "or" relationship.

[0041] 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).

[0042] 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.

[0043] 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.

[0044] Taking LD (Laser Diode) side-pumping as an example, it is an effective side-pumping scheme used to generate high-energy laser light by exciting a gain medium rod through a pump source (i.e., a laser diode), and also for laser amplification. The gain medium rod can be, for example, an ND:YLF crystal (neodymium-doped yttrium lithium fluoride crystal) or a Tm:YAG crystal (thulium-doped yttrium aluminum garnet crystal). LD side-pumping modules with a typical effective pump length of 10-100 mm have very large energy storage capabilities. However, compared to end-pumping, side-pumping results in relatively poor beam intensity distribution uniformity across the cross-section of the gain medium rod, and the uniformity of beam intensity distribution across the cross-section of the gain medium rod directly affects the uniformity of the output laser light.

[0045] To improve the uniformity of beam intensity distribution across the cross-section of the gain dielectric rod, multiple pump directions have become a standard approach. Here, pump direction refers to the number of light-receiving positions on the outer periphery of the gain dielectric rod's cross-section. Structurally, this is manifested by multiple pump modules distributed circumferentially along the gain dielectric rod, such as... Figure 1a The three-directional pumping scheme shown and Figure 1b The more pumping directions shown in the 5-directional pumping scheme, the more uniform the pump light intensity distribution across the cross-section of the gain dielectric rod.

[0046] The side structure of a traditional pump module is as follows Figure 2 As shown, multiple pump sources (LD bars in the figure) are along the axial direction of the gain dielectric bar. Figure 2 The rods are arranged closely together and assembled in a row that matches the length of the gain medium rods (in the direction shown by the Z-axis) to form a pump module.

[0047] In side-pumped solid-state lasers, the diameter of the gain medium rod determines the size of the output laser beam. Generally, the more pump directions there are, the more uniform the population inversion within the gain medium rod becomes. Based on this, and... Figure 1a Compared to the 3-directional pump, Figure 1b The 5-directional pumping in the gain medium rod can generate population inversion more uniformly, thus producing a more uniform circular laser beam that is closer to the TEM00 mode (fundamental mode), which is more ideal in many application scenarios.

[0048] Increasing the pump direction means requiring more pump modules and resulting in more pump light illuminating the gain dielectric rod. However, as the pump intensity increases, the gain saturation of the gain dielectric rod limits the intensity of pump light it can accept. Beyond the gain saturation threshold, further pump light cannot generate sufficient population inversion. High pump power can lead to overheating of the gain dielectric rod, reduced efficiency, and potentially trigger spontaneous emission amplification and non-radiative relaxation processes. More seriously, uneven thermal distribution across the cross-section of the gain dielectric rod can cause internal stress, which can lead to cracks. Therefore, to prevent these potential destructive conditions, pump lasers are generally not driven to maximum power.

[0049] In the pump modules currently used, to avoid too many unpumped areas between adjacent pump sources, as follows: Figure 3a Side view and Figure 3b As shown from the top view, multiple pump sources are arranged closely in a row. To prevent electrical short circuits between pump sources, adjacent pump sources are isolated from each other by small gaps. Since there is no heat dissipation structure between adjacent pump sources, these closely arranged pump sources heat each other during operation, resulting in thermal crosstalk. This heating effect is very serious and leads to a significant reduction in the lifespan of the pump sources, especially those located in the middle of the pump module.

[0050] Based on the above analysis, it can be concluded that in order to output a laser beam with a more uniform intensity distribution, the gain medium rod needs to generate a more uniform population inversion. Currently, a more uniform population inversion is achieved by having more pump directions. More pump directions mean more pump sources and higher pump power, which also leads to the corresponding heat generation problems of the gain medium rod and pump sources.

[0051] In view of this, in order to achieve a more uniform population inversion in the gain medium rod, that is, to ensure a more uniform intensity distribution of the output laser beam, and at the same time alleviate the heating problem of the gain medium rod and the pump source, this application considers to study and improve the method of achieving a more uniform population inversion by using fewer pump directions. Specifically, by using fewer pump directions, the pump light intensity on the cross-section of the gain medium rod is reduced as much as possible to alleviate the heating problem of the gain medium rod. Fewer pump directions are equivalent to fewer pump sources, so they can also alleviate the heating problem of the pump source. At the same time, by achieving a more uniform population inversion, the uniformity of the output laser intensity distribution of the gain medium rod is improved as much as possible to meet the needs of relevant application fields, including but not limited to solid-state lasers, solid-state amplifiers, high-power lasers, beam combining, etc.

[0052] According to one aspect of an embodiment of this application, a pumping assembly is provided, as detailed below. Figures 4 to 6 , Figure 4 The structure of the pump assembly is shown from the end face view. Figure 5 and Figure 6 The structure of the pump assembly is shown from two opposing side views. As shown in the figure, the pump assembly 100 includes a gain dielectric rod 110 and a plurality of pump sources 120, which are arranged in an axial (Z-axis direction in the figure) and circumferential array along the gain dielectric rod 110.

[0053] Multiple pump sources 120 are configured to emit light toward the gain dielectric rod 110, wherein multiple pump sources 120 arranged circumferentially and facing the same cross section of the gain dielectric rod 110 (e.g. Figure 4 Pump source B in 11 B 31 and B 51 Multiple pump sources 120 (e.g., spaced apart from each other and collinear along the direction shown by the Z-axis) are arranged at intervals. Figure 5 Pump source B in 11 and B 13 They are also set at intervals.

[0054] Multiple pump sources 120 facing the same cross-section of the gain dielectric rod 110 constitute a group of pump sources 120. Figures 4 to 6 In the specific embodiment shown, there are four sets of pump sources 120, of which B 11 B 31 and B 51 As a group, B 22 B 42 and B 62 As a group, B 13 B 33 and B 53 As a group, B 24 B 44 and B 64 One group; however, in other embodiments, there may be other numbers of groups. The projections of two adjacent groups of pump sources 120 along the Z-axis direction on the same plane are misaligned, meaning the projections of two adjacent groups of pump sources 120 along the Z-axis direction on the same plane do not coincide. Based on this, in Figure 4 From the end face view, B can be seen simultaneously. 11 B 31 B 51 This group of pump sources 120 and B 22 B 42 B 62 This set of pump sources is 120.

[0055] All pump sources 120 are connected in series to form at least one power supply line. Specifically, all pump sources 120 can be connected in series in the same power supply line, or the pump sources 120 can be divided into multiple groups, with each group's pump sources 120 connected in series in a power supply line, thus forming multiple power supply lines. After the circuit containing the pump source 120 is energized, the pump source 120... Figure 4 The light emitted by the dashed arrow points toward the gain dielectric rod 110, thereby exciting the gain dielectric rod 110 to output laser light.

[0056] Combination Figure 4 and Figure 5 It can be seen that in the pump assembly 100 provided in this application embodiment, if the gain dielectric rod 110 is divided into multiple parts along the axial direction ( Figure 5 The middle part (J1, J2, J3 and J4) has the same number of pumping directions in its cross-section, but the pumping angles are different. This allows the whole to be excited in a more uniform and concentric manner with fewer pumping directions, thereby achieving a more uniform population inversion. In this application, the entire gain medium rod 110 is actually effectively pumped from more directions.

[0057] It should be noted that, Figure 4 and Figure 5 The specific embodiment shown is only an exemplary solution. In other embodiments, the number of pump sources 120 may be different, and the number of pump directions may be more or less. No specific limitation is made here.

[0058] Using traditional solutions simultaneously Figure 1a Three-way pump and Figure 2 Taking the pump module as an example, the one provided in this application Figure 4 and Figure 5 Compared to the conventional approach, the total number of pump sources 120 (specifically 12) and the number of pump directions (specifically 3) remain unchanged in this embodiment. However, different sections of the cross-section of the gain dielectric rod 110 are effectively pumped from different angles. This allows the gain dielectric rod 110 as a whole to be effectively pumped from more angles. Specifically, in this example, the gain dielectric rod 110 is actually effectively pumped from six directions. Based on this, the gain dielectric rod 110 can generate a more uniform population inversion, resulting in a laser beam with a more uniform intensity distribution. Since the total number of pump sources 120 and the number of pump directions remain unchanged, it can be ensured that the pump power will not increase and the heating of the gain dielectric rod 110 will not be aggravated.

[0059] Furthermore, since the multiple pump sources 120 in this embodiment are arranged at intervals along both the circumferential and axial directions of the gain dielectric rod 110, the thermal crosstalk problem between the pump sources 120 can be effectively alleviated, thereby extending the service life of the pump sources 120. If it is desired that the pump sources 120 in this embodiment have the same service life as those in conventional embodiments, the driving current of the pump sources 120 can be increased compared to conventional embodiments to obtain more pump power, thereby increasing the output laser power of the gain dielectric rod 110.

[0060] Regarding the power supply circuit that enables the pump source 120 to operate and emit light, as mentioned above, three specific implementation methods are provided below:

[0061] In the first embodiment, all pump sources 120 are mounted on the same large annular heat sink (e.g., a water-conducting copper block). The pump sources 120 can be connected in series via welded interconnecting electrodes to form a power supply line, as detailed below. Figure 4 End face view Figure 5 One-sided view and Figure 6 From another perspective, for the example shown in the figure, it can be followed according to B. 11 B 31 B 51 B 62 B 42 B 22 B 13 B 33 B 53 B 64 B 44 B 24 This sequence can be chained together sequentially, or it can be done according to B. 11 B 13 B 24 B 22 B 31 B 33 B 44 B 42 B 51 B 53 B 64 B 62 This sequence can be used sequentially, but other sequences can also be used. The specific sequence is not limited here.

[0062] In the second embodiment, a ring of pump sources 120 arranged circumferentially is grouped together. Figures 4 to 6 The specific embodiment shown, pump source B 11 B 31 and B 51 As a group, pump source B 22 B 42and B 62 As a group, pump source B 13 B 33 and B 53 As a group, pump source B 24 B 44 and B 64 Multiple pump sources 120 arranged circumferentially in each group are assembled on an annular heat sink to form an annular pump module. The multiple pump sources 120 in each pump module can be connected in series via welded interconnecting electrodes to form a power supply line. A positive and negative lead-out electrode is provided at both ends of this power supply line to connect to the power source, thereby supplying power to each group of pump sources 120. Multiple annular heat sinks can be assembled and fixed together by end-face contact and screw connections to form the pump assembly 100.

[0063] In the third embodiment, the row of pump sources 120 arranged axially is grouped together. Figures 4 to 6 The specific embodiment shown, B 11 and B 13 As a group, B 22 and B 24 As a group, B 31 and B 33 As a group, B 42 and B 44 As a group, B 51 and B 53 As a group, B 62 and B 64 Each pump source 120 in a group is assembled on a strip-shaped heat-conducting block to form a strip-shaped pump module. Multiple pump sources 120 in each pump module can also be connected in series to form a power supply line by means of welding interconnecting electrodes, and a power supply can be connected by setting positive and negative lead electrodes at both ends of the power supply line.

[0064] Compared to the integrated assembly in the first embodiment and the ring-shaped pump module in the second embodiment, the strip-shaped pump module in the third embodiment has a simpler structure, which facilitates the processing, manufacturing and assembly of the pump module, thereby helping to reduce production costs.

[0065] In the third embodiment, multiple strip-shaped pump modules can be further assembled onto a larger annular heat sink to form an integrated pump assembly 100.

[0066] Based on the third implementation method described above, this application provides a specific embodiment. Please refer to [link to specific implementation method]. Figure 7The end face structure includes multiple pump modules 130 divided into a first module group 131 and a second module group 132, with the first module group 131 and the second module group 132 containing an equal number of pump modules 130. Please refer to [further details omitted]. Figure 8a and Figure 8b The side structures of the pump modules 130 in the first module group 131 and the second module group 132 are shown. The pump modules 130 in the first module group 131 have the same structure, and each pump module 130 has a first gap 141 formed thereon. The pump modules 130 in the second module group 132 also have the same structure, and each pump module 130 has a second gap 142 formed thereon.

[0067] Combination Figure 7 , Figure 8a and Figure 8b The multiple pump modules 130 in the first module group 131 and the multiple pump modules 130 in the second module group 132 are interspersed along the circumferential direction of the gain dielectric rod 110, so that the pump sources 120 on the pump modules 130 in the first module group 131 are opposite to the second gap 142 on both sides of the circumferential direction, and the pump sources 120 on the pump modules 130 in the second module group 132 are opposite to the first gap 141 on both sides of the circumferential direction.

[0068] In this embodiment, a first module group 131 is composed of multiple pump modules 130 with identical structures, and a second module group 132 is composed of multiple pump modules 130 with identical structures. This ensures that the pump modules 130 have at most two different structural forms, which is beneficial for the mass production of the pump modules 130 and thus reduces the required manufacturing cost. Based on this, the multiple pump modules 130 in the first module group 131 and the multiple pump modules 130 in the second module group 132 are arranged circumferentially, with the pump sources 120 on the pump modules 130 in the first module group 131 having their circumferential sides opposite to the second gaps 142 on the pump modules 130 in the second module group 132. The pump source 120 on the pump module 130 in the second module group 132 is opposite to the first gap 141 on the pump module 130 in the first module group 131 along both sides of the circumferential direction. This enables different parts of the cross section of the gain medium rod 110 to be effectively pumped from different angles, so that the gain medium rod 110 produces a more uniform population inversion, and outputs a laser beam with a more uniform energy distribution.

[0069] In order to further reduce production costs, such as Figure 8a and Figure 8b As shown, the pump module 130 in the first module group 131 has the same structure as the pump module 130 in the second module group 132. This allows the pump assembly 100 to be assembled simply by mass-producing the same pump modules 130, which helps to simplify the production process and reduce manufacturing costs.

[0070] exist Figure 8a Figure 8b In the specific embodiment shown, each pump module 130 includes two pump sources 120 and two gaps (i.e., a first gap 141 or a second gap 142), as shown. Figure 8a As shown, in the first module group 131, each pump module 130 has one end of a pump source 120 (i.e., Figure 8a The left end (as seen from the perspective) is set towards the negative Z-axis direction, such as... Figure 8b As shown, in the second module group 132, each pump module 130 has one end of a pump source 120 (i.e., Figure 8b The right end (from the perspective) is set towards the positive Z-axis direction, so that under the condition that all pump modules 130 have the same structure, the layout of each pump source 120 is staggered, which meets the requirement that different parts of the cross section of the gain medium rod 110 are effectively pumped from different angles.

[0071] In traditional pumping schemes, to ensure uniform pump intensity distribution along the gain dielectric rod, all pump modules are arranged at equal intervals along the circumference of the gain dielectric rod, and the pumping directions are typically odd-numbered, such as... Figure 1a The three directions shown Figure 1b The five directions, or even seven or more, shown are because if an even number of pump directions are used, there will be two pump modules emitting light in opposite directions along the radial direction of the gain dielectric rod. The beam emitted by one of these pump modules may damage the other pump module.

[0072] In order to ensure the uniformity of the pump intensity distribution on the gain dielectric rod 110, this application, such as Figure 7 As shown, a similar layout can be adopted, in which multiple pump modules 130 are arranged at equal intervals along the circumference of the gain dielectric rod 110. Based on this, from... Figure 7 From the end face view, although there are two opposing pump modules 130 along the radial direction of the gain dielectric rod 110, the two opposing pump modules 130 belong to the first module group 131 and the second module group 132 respectively, and according to Figure 8a and Figure 8bAs can be seen, in the two opposing pump modules 130, the location of the pump source 120 on the pump module 130 belonging to the first module group 131 (equivalent to the area of ​​the output beam) and the location of the pump source 120 on the pump module 130 belonging to the second module group 132 are offset from each other along the radial direction of the gain medium rod 110. This makes a small portion of the laser emitted by the pump source 120 on the pump module 130 belonging to the first module group 131 penetrate the gain medium rod 110 and reach the first gap 141, instead of reaching the pump source 120 on the other pump module 130 belonging to the second module group 132, thereby preventing the pump sources 120 from interfering with each other.

[0073] It should be noted that, in Figure 7 , Figure 8a and Figure 8b In the specific embodiment shown, three pumping directions, six pumping modules 130, and twelve pump sources 120 are used. This does not constitute a limitation on the parameters of the pumping assembly 100 provided in this application. Based on the core idea of ​​pumping from different angles on different parts of the cross-section of the gain dielectric rod 110 proposed in this application, any number of pumping directions, pumping modules, and pump sources should fall within the protection scope of this application.

[0074] In addition, in this embodiment, the plurality of pump sources 120 on each pump module 130 can also be arranged at equal intervals along the axial direction of the gain medium bar 110 to ensure that the various parts pumped from the same angle on the gain medium bar 110 have the same axial dimensions.

[0075] As mentioned above, the pump modules currently used reserve small gaps between adjacent pump sources for electrical isolation in order to avoid electrical short circuits between pump sources. Since these small gaps do not output pump light, unpumped regions are formed on the gain dielectric rod at positions opposite to these gaps along the radial direction. These unpumped regions not only do not participate in population inversion, but also absorb laser radiation, which actually increases the energy loss in the pump cavity.

[0076] In view of the above problems, based on the arrangement of multiple pump sources 120 on each pump module 130 at equal intervals along the axial direction of the gain dielectric rod 110, further, in each pump module 130, along the axial direction of the gain dielectric rod 110, the minimum distance between two adjacent pump sources 120 is equal to the size of one pump source 120, that is, as shown below. Figure 5 As shown, the minimum distance L1 between two adjacent pump sources 120 is equal to the size L2 of one pump source 120. This configuration ensures a continuous pumping region is formed in the middle of the gain dielectric rod 110, that is... Figure 5The J1, J2, J3 and J4 sections on the medium gain dielectric rod are continuous, thereby reducing the energy loss of the pump assembly 100 and enabling the gain dielectric rod 110 to output a laser beam with higher power and more uniform intensity distribution.

[0077] To improve the heat dissipation efficiency of the pump source 120, such as Figure 9 In one embodiment shown, the pump module 130 is depicted in a top view. Within each pump module 130, a heat-conducting block 150 can be disposed between two adjacent pump sources 120. The heat-conducting block 150 is used to conduct heat generated by the pump sources 120 to the outside. The heat-conducting block 150 can be made of a metal block with high thermal conductivity, such as copper or aluminum, and requires insulation treatment to ensure that the heat-conducting block is insulated from the pump sources 120 to prevent electrical short circuits. Alternatively, the heat-conducting block 150 can be made of an insulating material with high thermal conductivity, such as ceramic. To further improve heat conduction efficiency, a flowing coolant can be introduced into the heat-conducting block 150, thereby rapidly carrying away heat.

[0078] To improve the heat dissipation efficiency of the gain dielectric rod 110, such as Figure 7 As shown, a transparent flow tube 160 can be fitted onto the gain dielectric rod 110. Coolant 170 is introduced into the transparent flow tube 160 to carry away the heat of the gain dielectric rod 110, thereby achieving heat dissipation and cooling of the gain dielectric rod 110.

[0079] Finally, in order to more fully and intuitively demonstrate the effect of the pumping component provided in the embodiments of this application on the uniformity of particle population inversion, a conventional scheme and the scheme of this application are provided below based on the same components and pumping component parameters, and the energy level particle number distribution of the two schemes is detected and analyzed.

[0080] The pump source uses LD bar bars or LD bar bar arrays, and the gain dielectric rod uses Tm:YAG crystal rods. The parameters of the pump components in the traditional scheme and the scheme of this application are the same, as shown in Table 1 below:

[0081] Table 1: Parameters of the pump components in the conventional solution and the solution of this application

[0082] parameter value Gain dielectric rod diameter [mm] 4 Number of pump directions 3 Total number of pump sources 15 Inner diameter of transparent flow tube [mm] 6 Transparent flow tube wall thickness [mm] 2 Refractive index of coolant inside transparent flow tube 1.33 <![CDATA[Doping concentration of gain medium rod [1 / m 3 > <![CDATA[4.83×10 26 ]]> <![CDATA[Absorption cross-section of the gain medium rod [m 2 > <![CDATA[7.5×10 -25 ]]> Refractive index of gain dielectric rod 1.82 Refractive index of transparent flow tube 1.45 Pump source fast-axis divergence angle (FWHM, deg) 36.91 Pump source slow-axis divergence angle (FWHM, deg) 10

[0083] In traditional solutions, the end-face structure of the pump assembly and the top-view structure of the pump module are respectively as follows: Figure 1a and Figure 3b As shown in the figure, the pump light power distribution along the axial direction of the gain dielectric rod is as follows: Figure 10a and Figure 10bAs shown, the pump light power distribution along the gain medium rod axis directly reflects the laser upper level particle number distribution along the gain medium rod axis.

[0084] In the solution provided in this application, the end face structure of the pump assembly 100 is as follows: Figure 7 As shown, the top view of a single pump module 130 in the first module group 131 is as follows: Figure 9 As shown, a top view of a single pump module 130 in the second module group 132. Figure 11 As shown in the figure, the pump light power distribution along the axial direction of the gain dielectric rod 110 is as follows: Figure 12a and Figure 12b As shown.

[0085] Will Figure 12a , Figure 12b and Figure 10a , Figure 10b By comparison, it is clear that on the cross-section of the gain dielectric rod (the plane containing the x and y axes), Figure 12a and Figure 12b The pump light power distribution in the pump component 100 is more uniform. In other words, compared with the traditional solution, the number of laser upper energy level particles in the pump component 100 provided in this application is more uniform along the axis of the gain medium rod 110, which is conducive to the output of a laser beam with a more uniform energy distribution, making it more ideal for specific applications.

[0086] According to another aspect of the embodiments of this application, a solid-state laser is also provided, which includes the pump component 100 in any of the above embodiments.

[0087] Specifically, solid-state lasers can be applied in fields such as intelligent manufacturing, industrial processing, materials processing, scientific research, medical aesthetics, and laser ranging. They can also be used as solid-state amplifiers for signal power amplification. The solid-state laser provided in this application, by employing the pump component 100 provided in the above embodiments, can achieve more uniform population inversion with fewer pump directions, thereby outputting a laser beam with a more uniform energy distribution, reaching a more ideal state. Furthermore, because the pump sources 120 are spaced apart, thermal crosstalk problems are mitigated, allowing each pump source 120 to fully utilize its pump power, resulting in a relatively smaller number of required pump sources 120. In addition, based on the mitigation of thermal crosstalk problems between pump sources 120, if the pump sources 120 are to maintain the same lifespan as in conventional solutions, the current driving the pump sources 120 can be increased, thereby obtaining more pump power and laser output power while maintaining the original lifespan of the solid-state laser.

[0088] 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 pump assembly, characterized in that, include: A gain dielectric rod and multiple pump sources are arranged in an axial and circumferential array along the gain dielectric rod; Multiple pump sources are configured to emit light toward the gain dielectric rod, wherein multiple pump sources arranged circumferentially and facing the same cross section of the gain dielectric rod are spaced apart from each other, and multiple pump sources collinear along the axial direction are also spaced apart from each other. Multiple pump sources facing the same cross section of the gain dielectric rod constitute a group of pump sources, and the projections of two adjacent groups of pump sources on the same plane along the axial direction are staggered. All pump sources are connected in series to form at least one power supply line. The pump sources are used to emit light toward the gain dielectric rod when energized, so as to excite the gain dielectric rod to output laser.

2. The pump assembly according to claim 1, characterized in that, The pump assembly includes multiple strip-shaped pump modules, and each pump module extends along the axial direction; The pump module includes a plurality of pump sources arranged and fixed along the axial direction, with the plurality of pump sources in each pump module connected in series.

3. The pump assembly according to claim 2, characterized in that, Multiple pump modules are arranged at equal intervals along the circumference.

4. The pump assembly according to claim 2, characterized in that, Multiple pump sources on each pump module are arranged at equal intervals along the axial direction.

5. The pump assembly according to claim 4, characterized in that, In each pump module, along the axial direction, the minimum distance between two adjacent pump sources is equal to the size of one pump source.

6. The pump assembly according to claim 2, characterized in that, In each pump module, a heat-conducting block is placed between two adjacent pump sources.

7. The pump assembly according to any one of claims 2-6, characterized in that, Multiple pump modules are divided into a first module group and a second module group, and the first module group and the second module group contain the same number of pump modules; The multiple pump modules in the first module group have the same structure, and each pump module has a first gap formed on it; The multiple pump modules in the second module group have the same structure, and a second gap is formed on each pump module; The pump modules in the first module group and the pump modules in the second module group are interspersed along the circumferential direction, such that the pump sources on the pump modules in the first module group are opposite to the second gap on both sides of the circumferential direction, and the pump sources on the pump modules in the second module group are opposite to the first gap on both sides of the circumferential direction.

8. The pump assembly according to claim 7, characterized in that, The pump module in the first module group has the same structure as the pump module in the second module group.

9. The pump assembly according to any one of claims 2-6, characterized in that, A transparent flow tube is fitted onto the gain dielectric rod, and coolant is introduced into the transparent flow tube to dissipate heat and cool the gain dielectric rod.

10. A solid-state laser, characterized in that, Includes the pump assembly according to any one of claims 1-9.

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