Pump assembly and solid-state laser

Abstract

The present application relates to the technical field of laser devices. Disclosed are a pump assembly and a solid-state laser. The pump assembly comprises: a gain medium rod and a plurality of pump sources, wherein the plurality of pump sources are arranged in an array in the axial and circumferential directions of the gain medium rod; the plurality of pump sources are all configured to emit light towards the gain medium rod; a plurality of pump sources arranged in the circumferential direction and facing the same cross section of the gain medium rod are spaced apart from each other, and a plurality of pump sources which are collinear in the axial direction are also spaced apart from each other; the plurality of pump sources facing the same cross section of the gain medium rod form a group of pump sources; the projections of two adjacent groups of pump sources on the same plane in the axial direction are staggered from each other; all the pump sources are connected in series to form at least one power supply circuit; and the pump sources are configured to emit light towards the gain medium rod when energized, so as to excite the gain medium rod to output laser light. By means of the above manner, the present application can alleviate the heat generation problem of the gain medium rod and the pump sources on the basis of ensuring that the output laser light has relatively good uniformity.

Description

Pump components and solid-state lasers 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] Figures 1a and 1b show the 3-directional pumping scheme and the 5-directional pumping scheme in the prior art, respectively;

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

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

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

[0026] Figures 5 and 6 are side views of the pump assembly shown in Figure 4 on opposite sides.

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

[0028] Figure 8a is a 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 is 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 is a top view of a pump module with a heat-conducting block provided in an embodiment of the present invention;

[0031] Figures 10a and 10b show the pump light power distribution along the gain dielectric rod axis from the stereo view and the end face view, respectively, in the traditional scheme.

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

[0033] Figures 12a and 12b are respectively the pump light power distribution along the axial direction of the gain dielectric rod from a stereoscopic view and an end-face view in the embodiment of the present invention.

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

[0035] 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.

[0036] 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.

[0037] 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.

[0038] 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.

[0039] 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.

[0040] 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).

[0041] 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.

[0042] 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.

[0043] 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.

[0044] To improve the uniformity of beam intensity distribution across the cross-section of the gain dielectric rod, multiple pump directions have been adopted as a standard method. 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 along the circumference of the gain dielectric rod, as shown in the 3-direction pump scheme in Figure 1a and the 5-direction pump scheme in Figure 1b. The more pump directions there are, the more uniform the pump light intensity distribution across the cross-section of the gain dielectric rod.

[0045] The side structure of a traditional pump module is shown in Figure 2. Multiple pump sources (LD bars in the figure) are closely arranged along the axial direction of the gain dielectric bar (the direction shown by the Z-axis in Figure 2) and assembled into a row that matches the length of the gain dielectric bar, thus forming a pump module.

[0046] In side-pumped solid-state lasers, the diameter of the gain medium rod determines the size of the output laser beam. Generally, the more pumping directions there are, the more uniform the population inversion in the gain medium rod becomes. Based on this, compared to the 3-directional pumping in Figure 1a, the 5-directional pumping in Figure 1b can generate population inversion more uniformly in the gain medium rod, thus producing a more uniform, circular laser beam that is closer to the TEM00 mode (fundamental mode), which is more ideal in many applications.

[0047] 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.

[0048] In current pump modules, to avoid excessive unpumped areas between adjacent pump sources, multiple pump sources are arranged closely in a row, as shown in the side view of Figure 3a and the top view of Figure 3b. 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 significantly reduces the lifespan of the pump sources, especially those located in the middle of the pump module.

[0049] 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.

[0050] 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.

[0051] According to one aspect of the embodiments of this application, a pumping assembly is provided. Please refer to Figures 4 to 6 for details. Figure 4 shows the structure of the pumping assembly from an end-face view, and Figures 5 and 6 show the structure of the pumping assembly from two opposite side views, respectively. As shown in the figures, the pumping 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 figures) and circumferential array along the gain dielectric rod 110.

[0052] 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., pump source B in Figure 4) 11 B 31 and B 51 Multiple pump sources 120 (e.g., pump source B in Figure 5) are spaced apart from each other and collinear along the direction shown by the Z-axis. 11 and B 13 They are also set at intervals.

[0053] Multiple pump sources 120 facing the same cross section of the gain dielectric rod 110 constitute a group of pump sources 120. In the specific embodiments shown in Figures 4 to 6, there are four groups of pump sources 120, of which B 11 B 31 and B 51 As a group, B 22 B 42 and B62 As a group, B 13 B 33 and B 53 As a group, B 24 B 44 and B 64 One group is used, but in other embodiments, there can be other numbers of groups. The projections of two adjacent groups of pump sources 120 along the Z-axis on the same plane are misaligned, that is, the projections of two adjacent groups of pump sources 120 along the Z-axis on the same plane do not coincide. Based on this, in the end-face view of Figure 4, 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.

[0054] 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 emits light towards the gain dielectric rod 110 as shown by the dashed arrow in Figure 4, thereby exciting the gain dielectric rod 110 to output laser light.

[0055] As can be seen from Figures 4 and 5, 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 (parts J1, J2, J3 and J4 in Figure 5), then the number of pumping directions in the cross section of each part is the same, 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. This is because in the solution of this application, the entire gain dielectric rod 110 is actually effectively pumped from more directions.

[0056] It should be noted that the specific embodiments shown in Figures 4 and 5 are only one 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.

[0057] Taking the conventional scheme that simultaneously employs the three-directional pumping shown in Figure 1a and the pumping module shown in Figure 2 as an example, the embodiments in Figures 4 and 5 provided in this application, compared with the conventional scheme, have the same total number of pump sources 120 (specifically 12) and the same number of pumping directions (specifically 3). However, the cross-sections of different parts 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, thereby outputting a laser beam with a more uniform intensity distribution. Since the total number of pump sources 120 and the number of pumping directions remain unchanged, it can be ensured that the pumping power will not increase and the heating of the gain dielectric rod 110 will not be aggravated.

[0058] 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.

[0059] 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:

[0060] 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 shown in Figure 4 (end view), Figure 5 (side view), and Figure 6 (other side view). For the example shown in the figures, it can be implemented 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 B42 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.

[0061] In the second embodiment, the pump sources 120 arranged in a ring along the circumference are grouped together. For the specific embodiments shown in Figures 4 to 6, pump source B 11 B 31 and B 51 As a group, pump source B 22 B 42 and 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.

[0062] In the third embodiment, the row of pump sources 120 arranged axially is grouped together. For the specific embodiments shown in Figures 4 to 6, 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.

[0063] 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.

[0064] 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.

[0065] Based on the third embodiment described above, this application provides a specific embodiment. First, please refer to the end face structure in FIG7. Multiple pump modules 130 are divided into a first module group 131 and a second module group 132, with the same number of pump modules 130 in both groups. Next, please refer to the side structure of the pump modules 130 in the first module group 131 and the second module group 132 in FIGS. 8a and 8b. The multiple pump modules 130 in the first module group 131 have identical structures, and each pump module 130 has a first gap 141 formed on it. The multiple pump modules 130 in the second module group 132 also have identical structures, and each pump module 130 has a second gap 142 formed on it.

[0066] Referring to Figures 7, 8a, and 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.

[0067] 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.

[0068] To further reduce production costs, as shown in Figures 8a and 8b, 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 simplifies the manufacturing process and reduces manufacturing costs.

[0069] In the specific embodiments shown in Figures 8a and 8b, each pump module 130 includes two pump sources 120 and two gaps (i.e., the first gap 141 or the second gap 142). As shown in Figure 8a, in the first module group 131, the end of the pump source 120 on each pump module 130 (i.e., the left end in the view of Figure 8a) is set towards the negative direction of the Z-axis. As shown in Figure 8b, in the second module group 132, the end of the pump source 120 on each pump module 130 (i.e., the right end in the view of Figure 8b) is set towards the positive direction of the Z-axis. In this way, under the condition that all pump modules 130 have the same structure, a layout in which the pump sources 120 are staggered can be formed to meet the requirement that different parts of the cross section of the gain dielectric rod 110 can be effectively pumped from different angles.

[0070] In traditional pumping schemes, in order to ensure the uniformity of pump intensity distribution on the gain dielectric rod, all pump modules are arranged at equal intervals along the circumference of the gain dielectric rod, and the pumping direction is usually odd-numbered, such as the 3-direction shown in Figure 1a, the 5-direction shown in Figure 1b, or even the 7-direction or more. This is because if an even-numbered pumping direction is 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 two pump modules may damage the other pump module.

[0071] To ensure the uniformity of the pump intensity distribution on the gain dielectric rod 110, as shown in Figure 7, this application can also adopt a layout in which multiple pump modules 130 are arranged at equal intervals along the circumference of the gain dielectric rod 110. Based on this, from the end-face view in Figure 7, although there are two opposing pump modules 130 along the radial direction of the gain dielectric rod 110, these two opposing pump modules 130 belong to the first module group 131 and the second module group 132, respectively. As can be seen from Figures 8a and 8b, of the two opposing pump modules 130, those belonging to the first module group 131... The location of the pump source 120 on the pump module 130 (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 means that a small portion of the laser emitted by the pump source 120 on the pump module 130 belonging to the first module group 131 will penetrate the gain medium rod 110 and reach the first gap 141, instead of reaching the pump source 120 of the other pump module 130 belonging to the second module group 132, thereby preventing the pump sources 120 from interfering with each other.

[0072] It should be noted that in the specific embodiments shown in Figures 7, 8a, and 8b, three pumping directions, six pumping modules 130, and twelve pumping 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 pumping sources should fall within the protection scope of this application.

[0073] 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.

[0074] 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.

[0075] 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 in Figure 5, the minimum distance L1 between two adjacent pump sources 120 is equal to the size L2 of one pump source 120. After this arrangement, it can be ensured that a continuous pumping region is formed in the middle of the gain dielectric rod 110, that is, the J1, J2, J3 and J4 parts on the gain dielectric rod in Figure 5 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.

[0076] To improve the heat dissipation efficiency of the pump source 120, as shown in the top view of the pump module 130 in one embodiment (Figure 9), a heat-conducting block 150 can be placed between two adjacent pump sources 120 in each pump module 130. The heat-conducting block 150 is used to conduct the heat generated by the pump source 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 needs to be insulated to ensure that the heat-conducting block is insulated from the pump source 120 to prevent electrical short circuits. Of course, the heat-conducting block 150 can also be made of an insulating material with high thermal conductivity, such as ceramic. To further improve the heat conduction efficiency, a flowing coolant can also be introduced into the heat-conducting block 150 to quickly remove heat.

[0077] To improve the heat dissipation efficiency of the gain dielectric rod 110, as shown in Figure 7, 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 through the coolant 170, thereby achieving heat dissipation and cooling of the gain dielectric rod 110.

[0078] 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.

[0079] 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:

[0080] Table 1: Parameters of the pump components in the conventional solution and the solution of this application

[0081] In the traditional scheme, the end face structure of the pump component and the top view structure of the pump module are shown in Figure 1a and Figure 3b, respectively. After testing, the pump light power distribution along the gain medium rod axis is shown in Figure 10a and Figure 10b. 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.

[0082] In the solution provided in this application, the end face structure of the pump assembly 100 is shown in Figure 7, the top view structure of a single pump module 130 in the first module group 131 is shown in Figure 9, and the top view structure of a single pump module 130 in the second module group 132 is shown in Figure 11. After testing, the pump light power distribution along the axial direction of the gain dielectric rod 110 is shown in Figures 12a and 12b.

[0083] Comparing Figures 12a and 12b with Figures 10a and 10b, it is evident that the pump power distribution in Figures 12a and 12b is more uniform on the cross-section (plane containing the x and y axes) of the gain medium rod. In other words, compared with the traditional scheme, the pump component 100 provided by this application has a more uniform distribution of laser upper energy level particles along the axial direction of the gain medium rod 110, which is beneficial for the gain medium rod 110 to output a laser beam with a more uniform energy distribution, making it more ideal for specific applications.

[0084] 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.

[0085] 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.

[0086] 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 pumping assembly characterized by, 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 pumping assembly of claim 1, wherein, 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 pumping assembly of claim 2, wherein, Multiple pump modules are arranged at equal intervals along the circumference.

4. The pumping assembly of claim 2, wherein, Multiple pump sources on each pump module are arranged at equal intervals along the axial direction.

5. The pumping assembly of claim 4, wherein, 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 pumping assembly of claim 2, wherein, In each pump module, a heat-conducting block is placed between two adjacent pump sources.

7. The pumping assembly of any one of claims 2-6, wherein, 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 pumping assembly of claim 7, wherein, The pump module in the first module group has the same structure as the pump module in the second module group.

9. The pumping assembly of any one of claims 2-6, wherein, 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 by Includes the pump assembly according to any one of claims 1-9.

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