Liquid Cooling Structure of Optical Module and Optical Module

Abstract

This application discloses a liquid cooling structure and an optical module for an optical module. The liquid cooling structure includes a heat sink (100) and a heat conduction layer (200). The heat sink (100) includes a coolant inlet port (110) and a coolant outlet port (120). The coolant inlet port (110) and the coolant outlet port (120) communicate with the cavity of the heat sink (100) to form a coolant flow path. The heat conduction layer (200) is coated on the upper surface and / or the lower surface of the heat sink (100). The heat conduction layer (200) contacts the heat generating assembly (300) to transfer the heat generated by the heat generating assembly (300) to the heat sink (100).

Description

Technical Field

[0001] This application is proposed based on a Chinese patent application with an application number of 202210733643.1 and an application date of June 27, 2022, and claims the priority of the Chinese patent application. The entire content of the Chinese patent application is incorporated herein by reference.

[0002] This application relates to the technical field of heat dissipation, and particularly to a liquid cooling structure for an optical module and an optical module.

Background Art

[0003] With the development of technology, the switching capacity of large-capacity and high-density chips has been gradually improved, and the proportion of power consumption of serializers (serdes) and pluggable optical modules in the overall power consumption of the device has increased. In order to solve the problem of high heat generation between optoelectronic interconnections, the industry is using co-packaged optics technology (CPO) to reduce the power consumption of the device.

[0004] In the implementation form of CPO, usually, an external light source is used to separate the light source and the modulator, thereby reducing the difficulty of the design of the optical engine and improving the reliability. Currently, air cooling means is the mainstream for the heat dissipation of the external light source of the device, but for high-power light sources such as the devices realized by the aforementioned CPO, a stronger heat dissipation capacity is required. Currently, the external laser small form-factor pluggable (ELSFP) module defined by the Optical Internetworking Forum (OIF) has a maximum power consumption of 56.4W with an 8-laser configuration, which far exceeds the heat dissipation capacity of general air-cooled optical modules.

Summary of the Invention

Problems to be Solved by the Invention

[0005] The following is an overview of the subject matter described in detail in this specification. This overview is not intended to limit the scope of the claims.

[0006] Embodiments of the present application provide a liquid cooling structure and an optical module for an optical module.

Means for Solving the Problems

[0007] In a first aspect, embodiments of the present application a heat dissipation plate including a coolant inlet port and a coolant outlet port, wherein the coolant inlet port and the coolant outlet port communicate with a cavity of the heat dissipation plate to form a coolant flow path, and a heat conduction layer coated on the upper surface and / or the lower surface of the heat dissipation plate and in contact with a heat generating assembly of the optical module to transfer heat generated by the heat generating assembly to the heat dissipation plate, to provide a liquid cooling structure for the optical module.

[0008] In a second aspect, embodiments of the present application a heat generating assembly, and a liquid cooling structure including a heat dissipation plate and a heat conduction layer, wherein the heat dissipation plate includes a coolant inlet port and a coolant outlet port, the coolant inlet port and the coolant outlet port communicate with a cavity of the heat dissipation plate to form a coolant flow path, the heat conduction layer is coated on the upper surface and / or the lower surface of the heat dissipation plate, and the heat conduction layer is in contact with the heat generating assembly to transfer heat generated by the heat generating assembly to the heat dissipation plate, to provide an optical module.

[0009] Other features and advantages of the present application are described in the following specification, will be partially apparent from the specification, or will be understood by implementing the present application. The objectives and other advantages of the present application can be achieved and obtained by the configurations particularly shown in the specification, the claims and the accompanying drawings. The drawings are provided for understanding the technical solutions of the present application, form a part of this specification, and are used to explain the technical solutions of the present application together with the embodiments of the present application, and do not limit the technical solutions of the present application.

Brief Description of the Drawings

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Embodiments for Carrying Out the Invention

[0011] To make the objectives, technical solutions and advantages of the present application clearer, the present application will be described in more detail below with reference to the drawings and embodiments. The specific embodiments described in this specification are for the purpose of explaining the present application and not for limiting the present application.

[0012] In the specification of the present application and the above drawings, terms such as "first", "second", "third", "fourth", etc. (if any) are terms for distinguishing similar objects, and are not necessarily used to explain a specific order or sequence. Data used in this way is interchangeable where appropriate. For example, the embodiments of the present application described in this specification can be implemented in an order other than, for example, those shown or described in this specification. Further, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or apparatus comprising a series of steps or units need not be limited to the steps or units explicitly described, and may include other steps or units not explicitly described or inherent to these processes, methods, products or apparatuses.

[0013] In the present application, "at least one (item)" means one or more, and "a plurality" means two or more. "And / or" is used to describe the relationship of related objects, indicating that three types of relationships can exist. For example, "A and / or B" can indicate three cases: only A, only B, and A and B. Here, A and B can be singular or plural. The symbol " / " generally indicates that the related objects before and after are in an "or" relationship. "At least one (piece) of the following" or similar expressions mean any combination of these items, including any combination of one (piece) or more (pieces). For example, at least one (piece) of a, b or c can represent a, b, c, "a and b", "a and c", "b and c", or "a, b and c". Here, a, b, and c can be one or plural.

[0014] Note that in the description of the embodiments of the present application, the meaning of "a plurality (or a plurality of items)" is two or more. Understand that "greater than", "less than", "exceeding", etc. do not include the number, and "above", "below", "within", etc. include the number.

[0015] Currently, an optical module with a conventional capacity can meet the heat dissipation requirements by air cooling. However, a high-capacity optical module generates a large amount of heat, so the heat dissipation capacity of the conventional air cooling system cannot meet its heat dissipation requirements. For example, in the case of an ELSFP optical module using CPO technology, a more powerful heat dissipation method must be used as support. Optical modules are usually pluggable. Currently, a method to optimize the heat dissipation of a pluggable optical module is to contact a heat pipe or a vapor chamber with the shell of the ELSFP to improve the heat dissipation efficiency. However, due to the need for insertion and removal, the contact thermal resistance between the heat pipe or vapor chamber and the shell of the ELSFP is very large, and the above problems cannot be fundamentally solved.

[0016] Based on the above, the embodiments of the present application construct a coolant flow path in the cavity of the heat sink, and conduct heat by contacting the heat-generating assembly of the optical module with the heat sink through a heat conduction layer, thereby significantly improving the heat dissipation capacity compared with air cooling. A liquid cooling structure of an optical module and an optical module are provided. It can be applied to various devices using CPO chips, such as computer rooms in large-scale data centers, high-density high-performance computing (HPC) centers, and AI training devices.

[0017] Referring to FIG. 1, the liquid cooling structure of the optical module according to the embodiment of the present application is a heat sink 100 including a coolant inlet port 110 and a coolant outlet port 120, wherein the coolant inlet port 110 and the coolant outlet port 120 communicate with the cavity of the heat sink 100 to form a coolant flow path, and a heat conduction layer 200 coated on the upper surface and / or the lower surface of the heat sink 100 and in contact with the heat-generating assembly 300 of the optical module to transfer the heat generated by the heat-generating assembly 300 to the heat sink 100.

[0018] The heat sink 100 is configured to dissipate the heat generated by the heat-generating assembly 300 of the optical module, and usually presents a flat plate shape so as to be in close contact with the heat-generating assembly 300. Therefore, for the convenience of explanation below, in the following embodiments and drawings, the flat-plate heat sink 100 will be described. Both the upper surface and the lower surface of the heat sink 100 may be configured to contact the heat-generating assembly 300. In one heat sink 100, the heat-generating assembly 300 may be provided on either the upper surface or the lower surface thereof, or the heat-generating assembly 300 may be provided on both the upper surface and the lower surface.

[0019] Hereinafter, single-layer heat dissipation in which one heat-generating assembly 300 corresponds to one heat sink 100 will be described as an example.

[0020] As shown in FIG. 1, the heat sink 100 is provided with a heat conduction layer 200 on its upper surface. The heat conduction layer 200 contacts the heat-generating assembly 300 and transfers the heat generated by the heat-generating assembly 300 to the heat sink 100. A coolant inlet port 110 and a coolant outlet port 120 are provided on the side surface of the heat sink 100, and the coolant inlet port 110 and the coolant outlet port 120 communicate with the cavity of the heat sink 100. When coolant is supplied to the coolant inlet port 110, the coolant passes through the cavity of the heat sink 100 and is finally discharged from the coolant outlet port 120. In this way, the heat absorbed by the heat sink 100 can be effectively dissipated. The coolant inlet port 110 and the coolant outlet port 120 are connected to a coolant circulation system. The coolant that has absorbed heat dissipates heat in the coolant circulation system, the temperature drops, and it is pumped back to the coolant inlet port 110 again to exchange heat with the heat sink 100 again, and such a process is repeated.

[0021] Note that the form of the heat - generating assembly 300 is not limited and is usually a circuit board. The modules on the circuit board generate heat when operating. These modules include, but are not limited to, a power supply module, a laser generator, a control unit, etc. The heat generated by these modules is transmitted to the heat sink 100 through the circuit board and dissipated. To better implement heat conduction, a heat conduction layer 200 is provided between the heat - generating assembly 300 and the heat sink 100. The heat conduction layer 200 employs a high - thermal - conductivity material (TIM: Thermal Interface Material) with a high thermal conductivity such as thermal conduction grease. The TIM has a very low thermal resistance, can make good contact between the heat source and the cooling plate, and can maintain a high heat exchange capacity.

[0022] Hereinafter, two - layer heat dissipation in which two heat - generating assemblies 300 correspond to one heat sink 100 will be described as an example.

[0023] As shown in FIG. 2, the heat conduction layer 200 is provided on both the upper surface and the lower surface of the heat sink 100. The two heat - generating assemblies 300 are distributed on the upper side and the lower side of the heat sink 100 respectively, and transfer their respective heats to the heat sink 100 through the corresponding heat conduction layers 200. A coolant inlet port 110 and a coolant outlet port 120 are provided on the side surface of the heat sink 100. The coolant inlet port 110 and the coolant outlet port 120 communicate with the cavity of the heat sink 100 and are similarly coupled to the coolant circulation system. The coolant is circulated through the coolant inlet port 110 and the coolant outlet port 120, thereby continuously absorbing the heat from the heat sink 100, and in this way, a heat dissipation effect is obtained.

[0024] Similarly, in the two - layer heat dissipation structure, the form of the heat - generating assembly 300 is not limited. Since the heat conduction layer 200 supports heat conduction and ensures heat exchange efficiency as described above, a TIM with a high thermal conductivity may also be used.

[0025] In the above-described single-layer heat dissipation and two-layer heat dissipation embodiments, the cavity structure of the heat dissipation plate 100 may be designed according to actual needs. Hereinafter, these two configurations will be described.

[0026] In the first configuration, a coolant pipeline 130 is provided in the cavity of the heat dissipation plate 100. The coolant pipeline 130, together with the coolant inlet port 110 and the coolant outlet port 120, constitutes a coolant flow path. The structure of the coolant pipeline 130 is various. For example, the coolant pipeline 130 may be provided in the form of a coil tube within the cavity of the heat dissipation plate 100. The coil tube may be provided with only one turn, the orientation of the coil tube may be determined according to the heat generation region of the heat generating assembly 300, a plurality of turns of the coil tube may be provided on the plane of the heat dissipation plate 100, or the plurality of turns of the coil tube may be provided to be three-dimensionally distributed. The shape of the coil tube may be designed according to actual needs, but is not limited here. By the above method, as shown in FIG. 1, the heat of the heat dissipation plate 100 is sufficiently absorbed, and the heat dissipation effect is further enhanced.

[0027] In the second configuration, a coolant chamber is provided in the cavity of the heat dissipation plate 100. The coolant chamber communicates with the coolant inlet port 110 and the coolant outlet port 120 respectively. In such a configuration, the coolant is directly filled into the cavity, and the requirement for the support performance of the heat dissipation plate 100 is low. Therefore, the volume of the cavity can be designed according to the heat generation amount, the shape of the cavity can be adjusted according to the heat generation region of the heat generating assembly 300, or when a higher heat absorption efficiency is required, the thickness of the cavity can be made thinner or a bent flow path can be arranged in the cavity. The shape of the cavity may also be designed according to actual needs, but is not limited here. By the above method, the heat of the heat dissipation plate 100 is more sufficiently absorbed, and the heat dissipation effect is further enhanced.

[0028] Regarding the heat generating assembly 300, it was described above that the circuit board may be brought into contact with the heat conduction layer 200. However, in some cases, the module on the circuit board may also be brought into contact with the heat conduction layer 200. When the heights of the modules on the circuit board are relatively consistent, the tops of the modules will come into direct contact with the heat conduction layer 200, thereby achieving more direct heat conduction. Of course, in most cases, the heights of the modules on the circuit board are different and it is difficult to match the plate-shaped heat sink 100. Therefore, as shown in FIG. 3, grooves 140 are further provided on the upper surface and / or the lower surface of the heat sink 100, and the heat conduction layer 200 is coated in the grooves 140. Thereby, the heat generating assembly 300 or the heat generating module 320 of the heat generating assembly 300 is fitted into the grooves 140. Even when the module of the heat generating assembly 300 is fitted into the grooves 140 and the bottom of the grooves 140 is in close contact with the top of the heat generating module 320 by the heat conduction layer 200, more direct heat conduction can be achieved. Further, due to the grooves 140, the liquid cooling structure can be miniaturized, so it is more suitable for the miniaturized design of the product.

[0029] There may be a plurality of grooves 140, and their shapes may be designed as required, but are not limited here. In another possible embodiment, the grooves 140 are configured to be fitted into the circuit board instead of the modules on the circuit board.

[0030] In order to cooperate with the coolant circulation system and meet the needs of inserting and removing the optical module, one-touch couplers (not shown) are provided at the ends of the coolant inlet port 110 and the coolant outlet port 120. The one-touch couplers can easily connect the coolant flow path to the coolant circulation system. The one-touch couplers enable simple and convenient connection means, allow for insertion and removal connection multiple times, and also have a predetermined sealing property after connection, thus avoiding leakage of the coolant.

[0031] In addition, the coolant inlet ports 110 and the coolant outlet ports 120 of the plurality of liquid cooling structures can be combined. As shown in FIG. 4, in the case of three liquid cooling structures, the three coolant inlet ports 110 are combined into one inlet, and the three coolant outlet ports 120 are combined into one outlet. The combined inlet and outlet may be connected to the coolant circulation system. In some possible cases, in order to uniformly absorb the heat generated by the three liquid cooling structures through circulation, it is necessary to perform a flow uniformity design on the combined pipeline, but this will not be described in detail here.

[0032] The embodiment of the present application also provides an optical module including a heat generating assembly 300 and a liquid cooling structure. The liquid cooling structure includes a heat dissipation plate 100 and a heat conduction layer 200. The heat dissipation plate 100 includes a coolant inlet port 110 and a coolant outlet port 120. The coolant inlet port 110 and the coolant outlet port 120 communicate with the cavity of the heat dissipation plate 100 to form a coolant flow path. The heat conduction layer 200 is coated on the upper surface and / or the lower surface of the heat dissipation plate 100. The heat conduction layer 200 contacts the heat generating assembly 300 to transfer the heat generated by the heat generating assembly 300 to the heat dissipation plate 100.

[0033] The liquid cooling structure of the optical module in the embodiment of the present application is similar to the liquid cooling structure in the foregoing embodiment. Similarly, it has a heat dissipation plate 100 and a heat conduction layer 200. By connecting the heat conduction layer 200 between the heat generating assembly 300 and the heat dissipation plate 100, the heat generated by the heat generating assembly 300 is transferred to the heat dissipation plate 100, and liquid cooling heat dissipation is achieved.

[0034] As shown in FIG. 2 or FIG. 5, the heat generating assembly 300 of the optical module includes a heat generating module 320 and a main board 310. The heat generating module 320 is provided on one surface of the main board 310, and the other surface is connected to the heat conduction layer 200. In such a form, the heat generated by the heat generating module 320 is conducted to the heat sink 100 through the main board 310. The heat sink 100 can adopt a flat plate structure without special processing, and has high versatility. In another form, as shown in FIG. 3, grooves 140 are formed on the upper surface and / or the lower surface of the heat sink 100, and the heat conduction layer 200 is coated in the grooves 140. In this case, the heat generating assembly 300 is reversed, and one surface of the heat generating module 320 may face the grooves 140 and be fitted into the grooves 140. In this way, since the heat generating module 320 can be in direct contact with the heat sink 100, the heat dissipation performance is further improved, but it is necessary to open slots according to the heat generating assembly 300.

[0035] In some embodiments, as shown in FIGS. 6 to 9, the optical module further includes a front panel 410 and a rear panel 420. The front panel 410 includes a retractable clicker member 411, and the rear panel 420 includes an optical connector 421 and an electrical connector 422. The optical connector 421 and the electrical connector 422 connect to corresponding types of modules of the heat generating assembly 300. The optical module is elongate and is inserted into the device along its longitudinal direction when attached to the device. Therefore, in the embodiments of the present application, the front panel 410 and the rear panel 420 are relative. As shown in FIG. 8, the front panel 410 is the side of the optical module facing the operator during insertion and removal, and the rear panel 420 is the side of the optical module facing the device during insertion and removal. In the embodiments of the present application, the front panel 410 is provided with a clicker member 411 so that the operator can easily remove the optical module. After the removal operation is completed, the clicker member 411 may be pushed into the module, thereby reducing interference from external elements to the optical module. The rear panel 420 is provided with an optical connector 421 and an electrical connector 422. The optical connector 421 connects to a corresponding module on the heat generating assembly 300, such as a laser module, and the electrical connector 422 connects to a corresponding module on the heat generating assembly 300, such as a power supply module, a control unit, etc.

[0036] According to the foregoing liquid cooling structure, depending on the arrangement positions of the coolant inlet port 110 and the coolant outlet port 120, the optical module may have a front liquid supply and discharge structure or a rear liquid supply and discharge structure. Here, the front liquid supply and discharge structure means that the coolant inlet port 110 and the coolant outlet port 120 are provided through the front panel 410, and the rear liquid supply and discharge structure means that the coolant inlet port 110 and the coolant outlet port 120 are provided through the rear panel 420.

[0037] In some embodiments, in the front liquid supply and discharge structure, a through hole is formed in the front panel 410, and the coolant inlet port 110 and the coolant outlet port 120 penetrate through this through hole and face the operator side. As shown in FIGS. 6 and 8, after the operator inserts the optical module, an external coolant circulation system is connected to the coolant inlet port 110 and the coolant outlet port 120, thereby completing the installation. Since the coolant is supplied to the front panel 410, in this embodiment, a combination of an electrical connector and an optical connector is used. This simplifies the connector design and has the advantage of high reliability.

[0038] In the rear liquid supply and discharge structure, a through hole is formed in the rear panel 420, and the coolant inlet port 110 and the coolant outlet port 120 penetrate through this through hole and face the inside of the device. As shown in FIGS. 7 and 9, inside the device, connectors of the coolant circulation system are pre-installed. When the operator inserts the optical module into the device, the coolant inlet port 110 and the coolant outlet port 120 are aligned with the connectors of the coolant circulation system, thus completing the installation. In the environment where this module is used, the liquid cooling source is provided by the CPO device. Therefore, there is no need to supply the coolant from outside the device. In this way, the system has excellent cooling consistency and the advantage that heat dissipation by liquid cooling of the entire system is reliably achieved.

[0039] In some embodiments, the optical module further includes a side panel 430, and a guide rail 431 extending in the longitudinal direction of the optical module is provided on the side panel 430. The guide rail 431 of the side panel 430 is configured to assist in mounting the optical module. Thus, the optical module slot of the device may have a corresponding structure such as a groove, whereby it can fit with the guide rail 431 of the side panel 430 of the optical module and achieve a certain degree of foolproofness. The operator facilitates the installation by aligning the guide rail 431 with the groove in the optical module slot. Of course, there may be multiple guide rails 431. For example, three guide rails 431 may be distributed on two side surfaces, three side surfaces, or even the same side surface, as long as corresponding ones are arranged in the optical module slot.

[0040] In addition, a plurality of heat-generating assemblies 300 may be attached to the optical module, and one heat sink 100 is arranged for each or every two of the heat-generating assemblies 300. When two or more liquid cooling structures are included, each liquid cooling structure is arranged in layers, and the coolant inlet port 110 and the coolant outlet port 120 are respectively merged and connected to the coolant circulation system. For example, as shown in FIG. 5, the optical module includes three heat-generating assemblies 300, and one heat sink 100 is provided for each heat-generating assembly 300. The coolant inlet ports 110 and the coolant outlet ports 120 of the three heat sinks 100 are respectively merged, and a merged inlet and a merged outlet are drawn out from the front panel 410. Therefore, the rear panel 420 is provided with three optical connectors 421 and three electrical connectors 422 corresponding to the three heat-generating assemblies 300 respectively. Here, only three heat-generating assemblies 300 are illustrated, but since a maximum of two heat-generating assemblies 300 can be arranged for each heat sink 100, four, five, or six heat-generating assemblies 300 may be provided in this optical module.

[0041] As described above, in the heat sink 100 according to the embodiment of the present application, the heat conduction layer 200 contacts the heat generating assembly 300 of the optical module, so that the heat generated by the heat generating assembly 300 is transmitted to the heat sink 100. The heat sink 100 adopts a liquid cooling heat dissipation form, and a coolant inlet port 110 and a coolant outlet port 120 are provided. A coolant flow path is constructed together with the cavity of the heat sink 100. The coolant flow path exchanges heat with the heat generating assembly 300, and the heat generated by the heat generating assembly 300 is dissipated through the coolant. Thereby, a higher heat dissipation capacity than air cooling is obtained, the problem of heat generation of a large-capacity optical module is solved, and a larger laser output becomes possible.

[0042] The liquid cooling structure and the optical module according to the embodiment of the present application have at least the following beneficial effects. In the heat sink, the heat conduction layer contacts the heat generating assembly of the optical module, so that the heat generated by the heat generating assembly is transmitted to the heat sink. The heat sink adopts a liquid cooling heat dissipation form, and a coolant inlet port and a coolant outlet port are provided. A coolant flow path is constructed together with the cavity of the heat sink. The coolant flow path exchanges heat with the heat generating assembly, and the heat generated by the heat generating assembly is dissipated through the coolant. Thereby, a higher heat dissipation capacity than air cooling is obtained, the problem of heat generation of a large-capacity optical module is solved, and a larger laser output becomes possible.

[0043] As described above, some embodiments of the present application have been described. However, the present application is not limited to the above embodiments. Those skilled in the art may make various equivalent modifications and substitutions without departing from the scope of the present application. These equivalent modifications and substitutions are within the scope defined by the claims of the present application.

Claims

1. A liquid cooling structure for an optical module, comprising: A heat dissipation plate including a coolant inlet port and a coolant outlet port, wherein the coolant inlet port and the coolant outlet port communicate with a cavity of the heat dissipation plate to form a coolant flow path; A heat conduction layer coated on the upper surface and / or the lower surface of the heat dissipation plate, contacting a heat generating assembly of the optical module, and transferring heat generated by the heat generating assembly to the heat dissipation plate.

2. The liquid cooling structure according to claim 1, wherein a coolant pipeline is provided in the cavity of the heat dissipation plate, and the coolant pipeline constitutes a coolant flow path together with the coolant inlet port and the coolant outlet port.

3. The liquid cooling structure according to claim 2, wherein the coolant pipeline is provided in the form of a coil pipe.

4. The liquid cooling structure according to claim 1, wherein a coolant chamber is provided in the cavity of the heat dissipation plate, and the coolant chamber communicates with the coolant inlet port and the coolant outlet port respectively.

5. The liquid cooling structure according to claim 1, wherein grooves are further provided on the upper surface and / or the lower surface of the heat dissipation plate, and the heat conduction layer is coated in the grooves, whereby the heat generating assembly or the heat generating module of the heat generating assembly is fitted into the grooves.

6. The liquid cooling structure according to claim 1, wherein one-touch couplers are provided at the ends of the coolant inlet port and the coolant outlet port.

7. An optical module, comprising: A heat generating assembly; A liquid cooling structure including a heat dissipation plate and a heat conduction layer, wherein the heat dissipation plate includes a coolant inlet port and a coolant outlet port, the coolant inlet port and the coolant outlet port communicate with a cavity of the heat dissipation plate to form a coolant flow path, the heat conduction layer is coated on the upper surface and / or the lower surface of the heat dissipation plate, and the heat conduction layer contacts the heat generating assembly and transfers heat generated by the heat generating assembly to the heat dissipation plate.

8. The optical module according to claim 7, wherein the heat generating assembly includes a heat generating module and a main board, the heat generating module is provided on one surface of the main board, and the other surface of the main board is connected to the heat conduction layer.

9. The heating assembly includes a heating module and a main board configured to place the heating module thereon. Grooves are further provided on the upper surface and / or the lower surface of the heat dissipation plate, and the heat conduction layer is coated in the grooves. The main board or the heating module is fitted into the grooves. The optical module according to claim 7.

10. The optical module further includes a front panel and a rear panel. The front panel includes a retractable pachinko member. The rear panel includes an optical connector and an electrical connector. The optical connector and the electrical connector are configured to connect corresponding types of modules of the heating assembly. The optical module according to claim 7.

11. Either the coolant inlet port or the coolant outlet port penetrates through the front panel, or either the coolant inlet port or the coolant outlet port penetrates through the rear panel. The optical module according to claim 10.

12. When the coolant inlet port and the coolant outlet port are connected to the rear panel, the coolant inlet port and the coolant outlet port are connected to a coolant circulation system through the rear panel. The optical module according to claim 11.

13. The optical module according to claim 10 further includes a side panel provided with a guide rail extending in the longitudinal direction of the optical module.

14. When including two or more of the liquid cooling structures, each of the liquid cooling structures is arranged in layers, and the coolant inlet port and the coolant outlet port are respectively joined and connected to a coolant circulation system. The optical module according to any one of claims 7 to 13.

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