Optical module comprising a heat sink
Patent Information
- Application Number
- CN202522437427.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-17
- Publication Date
- 2026-10-09
- Estimated Expiration
- 2035-11-17
AI Technical Summary
[0003]现有的光模组会面临光功率、空间管理、热管理、插入损耗(Insertion loss)及制造良率(Manufacturing yield)等挑战
[0006]根据本实用新型实施例揭露的光模组，借由在诸如高功耗元件等的热源和导热壳体之间设置相较于导热壳体具有较大的导热系数的散热件，热源的热量会因小的总热阻而可有效地被传递到导热壳体来进行散热，从而实现优异的散热效率，降低热源的温升，保证了光模组的应用可靠性以及组装方便性。另外，导热壳体不与热源直接接触，使得热源因碰撞而毁损的问题不易发生。
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Figure CN224840590U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to an optical module that includes a heat sink. Background Technology
[0002] Optical modules can transmit and / or receive optical signals for applications such as, but not limited to, data centers, cable TV, and fiber-to-the-home (FTTH). Using optical modules for transmission can provide higher transmission rates and signal bandwidth over longer transmission distances. To promote the compatibility of global optical internet products and reduce maintenance burdens, organizations such as the Multi-Source Agreement (MSA), the Institute of Electrical and Electronics Engineers (IEEE), and the Optical Internetworking Forum (OIF) have developed several form factors suitable for different signal transmission rates. These form factors include, but are not limited to, XFP, SFP, QSFP (Quad Small Form Factor Pluggable), QSFP-DD (Double Density), OSFP (Octal Small Form Factor Pluggable), and CPO (Co-Packaged Optics).
[0003] Existing optical modules face challenges such as optical power, space management, thermal management, insertion loss, and manufacturing yield. Utility Model Content
[0004] The present invention provides an optical module including a heat sink.
[0005] An embodiment of this utility model discloses an optical module comprising a heat-conducting housing, a substrate, a heat source, a first heat-conducting medium, a heat sink, and a second heat-conducting medium. The substrate is located within the heat-conducting housing and has a first surface. The heat source is disposed on the first surface of the substrate. The first heat-conducting medium is disposed on the heat source. The heat source is located between the substrate and the first heat-conducting medium. The heat sink is disposed on the first heat-conducting medium. The second heat-conducting medium is disposed on the heat sink. The heat sink is thermally coupled to the heat-conducting housing through the second heat-conducting medium. The thermal conductivity of the heat sink is greater than that of the heat-conducting housing.
[0006] According to the optical module disclosed in this embodiment, by placing a heat sink with a higher thermal conductivity than the heat sink between a heat source (such as a high-power component) and a heat-conducting housing, the heat from the heat source can be effectively transferred to the heat-conducting housing for dissipation due to the low total thermal resistance. This achieves excellent heat dissipation efficiency, reduces the temperature rise of the heat source, and ensures the application reliability and ease of assembly of the optical module. Furthermore, since the heat-conducting housing does not directly contact the heat source, the problem of damage to the heat source due to impact is less likely to occur.
[0007] The above description of the present utility model and the following description of the embodiments are used to demonstrate and explain the spirit and principle of the present utility model, and to provide a further explanation of the protection scope of the present utility model. Attached Figure Description
[0008] Figure 1 This is a three-dimensional schematic diagram of an optical module according to an embodiment of the present invention.
[0009] Figure 2 for Figure 1 An exploded view of the optical module in the diagram.
[0010] Figure 3 for Figure 2 An enlarged schematic diagram of the heat sink of the optical module.
[0011] Figure 4 For along Figure 1 A schematic diagram of the side section taken from the XZ plane.
[0012] Figure 5 for Figure 2 A schematic diagram showing the heat transfer protrusion of the optical module and the projection of the heat source onto the first surface of the substrate.
[0013] Figure 6 This is a side sectional view of an optical module according to another embodiment of the present invention.
[0014] Figure 7 for Figure 6 A schematic diagram showing the heat dissipation section of the optical module and the projection of the heat source onto the first surface of the substrate.
[0015] [Explanation of Labels in the Attached Image]
[0016] 1,1a: Optical module
[0017] 10: Thermal conductive housing
[0018] 100: First heat-conducting housing
[0019] 101: Second heat-conducting shell
[0020] 101a: Spine
[0021] 102: External heat sink
[0022] 11: Substrate
[0023] 110: First Surface
[0024] 12: Heat source
[0025] 13: First heat transfer medium
[0026] 14, 14a: Heat sink
[0027] 140: Heat dissipation section
[0028] 1400: Second Surface
[0029] 141: Support section
[0030] 142: Heat transfer protrusion
[0031] 15: Second heat transfer medium
[0032] P1, P2, P3: Projection Detailed Implementation
[0033] The following disclosure describes the principles of this utility model and exemplary embodiments thereof, and may be illustrated with accompanying drawings as necessary. However, any description and drawings are not exhaustive enumeration of all embodiments of this utility model, nor are they intended to limit this utility model to a specific form. Those skilled in the art will understand from the disclosure that many modifications and variations are possible, and thus various implementation methods can be reasonably derived.
[0034] One type of optical module known to the inventors employs a boss protruding from a heat-conducting housing to dissipate heat from high-power components. In this type of optical module, heat is transferred from high-power components, such as digital signal processors (DSPs), to the boss protruding from the heat-conducting housing via a heat-conducting medium for dissipation. However, the large total thermal resistance between the heat-conducting medium and the boss makes it difficult for heat to be effectively transferred to the heat-conducting housing for dissipation. Another type of optical module known to the inventors often adds external components to improve heat dissipation, leading to excessively complex assembly. In particular, in optical modules with high transmission rates (e.g., 800Gbps and above), the heat dissipation efficiency of high-power components significantly affects transmission quality.
[0035] According to one embodiment of this utility model, by placing a heat sink with a higher thermal conductivity than the heat-conducting shell between a heat source (such as a high-power component) and the heat-conducting shell, the heat from the heat source can be effectively transferred to the heat-conducting shell for heat dissipation due to the low total thermal resistance. This achieves excellent heat dissipation efficiency, reduces the temperature rise of the heat source, and ensures the application reliability and ease of assembly of the optical module. Furthermore, since the heat-conducting shell does not directly contact the heat source, the problem of damage to the heat source due to impact is less likely to occur.
[0036] Furthermore, the heat sink according to one embodiment of the present invention is applicable to an eight-channel small pluggable (OSFP) optical module. Compared to SFP, QSFP, and QSFP-DD optical modules, OSFP optical modules have a larger internal space, thus allowing for the configuration of heat sinks with a larger projected area than high-power components, and also facilitating the configuration of support portions.
[0037] Those skilled in the art can reasonably combine and configure the following disclosed technical features to achieve the corresponding technical effects.
[0038] The terms “coupled” or “coupled” refer to any connection, link, or similar relationship, and “optical coupling” or “optical linking” refers to the relationship in which light is impparted from one element to another. Unless otherwise stated, elements that are coupled or linked to each other do not need to be directly connected to each other and can be separated by intermediate elements.
[0039] The term "substantially" refers to a degree of precision within an acceptable margin of error, where the acceptable margin of error is considered to reflect minute real-world variations resulting from material composition, material defects, and / or limitations / peculiarities during the manufacturing process. Such variations can therefore be described as achieving the stated characteristics to a large extent, but not necessarily completely.
[0040] Figure 1 This is a three-dimensional schematic diagram of an optical module 1 according to an embodiment of the present invention. Figure 2 for Figure 1 An exploded view of optical module 1 in the diagram. Figure 3 for Figure 2 An enlarged schematic diagram of the heat sink 14 of the optical module 1. Figure 4 For along Figure 1 A schematic diagram of the side section taken by the XZ plane, and Figure 5 for Figure 2 A schematic diagram of the projection of the heat transfer protrusion 142 of the optical module 1 and the heat source 12 onto the first surface 110 of the substrate 11.
[0041] According to one embodiment, optical module 1 can be a high-transmission-rate OSFP optical module. For example, optical module 1 can be an 800Gbps OSFP optical module, a 1.6Tbps OSFP optical module, or a 3.2Tbps OSFP optical module.
[0042] According to one embodiment, the optical module 1 may include a heat-conducting housing 10, a substrate 11, a heat source 12, a first heat-conducting medium 13, a heat sink 14, and a second heat-conducting medium 15.
[0043] In one embodiment, the heat-conducting housing 10 may be made of zinc alloy, wherein the thermal conductivity of zinc alloy is 116 W / m×K. In one embodiment, the heat-conducting housing 10 may include a first heat-conducting shell 100 and a second heat-conducting shell 101 coupled together.
[0044] In one embodiment, the substrate 11 may be located within the thermally conductive housing 10 and have a first surface 110. In one embodiment, the substrate 11 may be disposed within the first thermally conductive housing 100. In one embodiment, the substrate 11 may be a circuit board assembly (PCBA).
[0045] In one embodiment, the optical module 1 may further include an external heat sink 102. In one embodiment, as... Figure 1 and Figure 4 As shown, the second heat-conducting shell 101 may have two ridges 101a. An external heat sink 102 is thermally coupled to the outer surface of the second heat-conducting shell 101 and is located between the two ridges 101a. The external heat sink 102 may be an extruded aluminum heat sink or include snap-fit fins.
[0046] In one embodiment, the heat source 12 may be disposed on the first surface 110 of the substrate 11. The heat source 12 may be a high-power device. In one embodiment, the heat source 12 is a digital signal processor (DSP) chip, or a photonic chip integrating DSP chip functionality.
[0047] In one embodiment, the first thermally conductive medium 13 may be disposed on the heat source 12. In one embodiment, the heat source 12 may be located between the substrate 11 and the first thermally conductive medium 13. In one embodiment, the first thermally conductive medium 13 may be a thermally conductive pad or a thermally conductive gel.
[0048] In one embodiment, the heat sink 14 may be disposed on the first heat-conducting medium 13. In one embodiment, the thermal conductivity of the heat sink 14 may be greater than that of the heat-conducting housing 10. In one embodiment, the material of the heat sink 14 may be copper, wherein the thermal conductivity of copper is 386 W / m×K. In one embodiment, the heat sink 14 may be formed by cold forging or stamping. In one embodiment, the heat sink 14 may include a heat dissipation portion 140, two support portions 141, and a heat transfer protrusion 142. In one embodiment, the heat source 12 may be located between the substrate 11 and the heat transfer protrusion 142. In one embodiment, the heat dissipation portion 140 may have a second surface 1400. In one embodiment, the second surface 1400 may face the substrate 11. In one embodiment, the heat transfer protrusion 142 may protrude from the second surface 1400. In one embodiment, the two support portions 141 may protrude from the second surface 1400 and abut against the substrate 11 to position the heat transfer protrusion 142 and the heat source 12, thereby allowing the thickness of the first heat-conducting medium 13 to be sufficiently small, thereby reducing the thermal resistance of the first heat-conducting medium 13. In one embodiment, the heat dissipation portion 140, the two support portions 141 and the heat transfer protrusion 142 may be integrally formed.
[0049] In one embodiment, the width of the heat sink 14 may be greater than half the width of the substrate 11. For example... Figure 3 and Figure 4 As shown, the width refers to the dimension of the component in the X direction. The width of the heat sink 14 can be understood as the dimension of the heat dissipation portion 140 in the X direction, or as the distance in the X direction between the left side wall of the left support portion 141 and the right side wall of the right support portion 141. The width of the substrate 11 can be understood as the distance in the X direction between the left edge and the right edge of the substrate 11. A wider heat sink 14 can provide a larger heat transfer area. In one embodiment, the width of the heat sink 14 can be more than 90% of the width of the substrate 11, which can be achieved by bringing the side of the heat sink 14 as close as possible to the side edge of the substrate 11 without affecting the function of the substrate 11 (such as signal transmission wiring).
[0050] As mentioned above, the support portion 141 facilitates obtaining a thin first thermally conductive medium 13. In order to achieve this through the thickness of the support portion 141 (i.e., Figure 3 The thickness of the first thermally conductive medium 13 is determined by the dimension in the Z direction, and the heat source 12 can be located between the two supports 141 in the X direction. Furthermore, in order to provide a uniform gap at various points above the heat source 12 for the heat sink 14 mounted on the first surface 110 of the substrate 11, the length of the support 141 (i.e., the dimension in the Z direction) is determined. Figure 3 The dimension in the Y direction can be greater than the length of the heat source 12.
[0051] In one embodiment, the area of the projection P1 of the heat transfer protrusion 142 on the first surface 110 of the substrate 11 can be larger than the area of the projection P2 of the heat source 12 on the first surface 110 of the substrate 11, thereby ensuring that the heat source 12 can make complete thermal contact with the heat transfer protrusion 142. In addition, the projection area of the heat dissipation portion 140 on the first surface 110 can be larger than the area of the projection P1 of the heat transfer protrusion 142 on the first surface 110, which is beneficial to improving the heat dissipation efficiency of heat transfer from the heat transfer protrusion 142 to the second heat-conducting medium 15.
[0052] In one embodiment, the second thermally conductive medium 15 may be disposed on the heat sink 14. In one embodiment, the heat sink 14 may be thermally coupled to the heat-conducting housing 10 via the second thermally conductive medium 15. In one embodiment, the heat sink 14 may be thermally coupled to the second heat-conducting housing 101 via the second thermally conductive medium 15. In one embodiment, the second thermally conductive medium 15 and the first thermally conductive medium 13 may be made of the same material. In one embodiment, both the first thermally conductive medium 13 and the second thermally conductive medium 15 may be thermally conductive gels. In one embodiment, the thickness of the second thermally conductive medium 15 may be greater than the thickness of the first thermally conductive medium 13. In one embodiment, by thinning the first thermally conductive medium 13, the thickness of the second thermally conductive medium 15 can be increased to prevent collisions between components during transport due to tolerance issues.
[0053] It should be noted that the thermal resistance of a medium can be calculated using the following formula 1.
[0054] Equation 1: R = L / (A × k);
[0055] Where R is the thermal resistance of the medium, L is the thickness of the medium, A is the area of the medium, and k is the thermal conductivity of the medium. As can be seen from Equation 1, the smaller the thickness of the medium, the larger the area of the medium, or the larger the thermal conductivity of the medium, the smaller the thermal resistance of the medium.
[0056] In one embodiment, the total thermal resistance is the sum of the thermal resistance of the first thermally conductive medium 13, the thermal resistance of the heat dissipation portion 140, the thermal resistance of the heat transfer protrusion 142, and the thermal resistance of the second thermally conductive medium 15.
[0057] It should be noted that the term "total thermal resistance" used in this article refers to the sum of the thermal resistances of all media between a heat source and the heat-conducting housing in the optical module. For example, when the heat from a heat source is transferred to the heat-conducting housing through the first thermally conductive medium, the heat dissipation part, the heat transfer protrusion, and the second thermally conductive medium, the total thermal resistance is the sum of the thermal resistances of the first thermally conductive medium, the heat dissipation part, the heat transfer protrusion, and the second thermally conductive medium.
[0058] Table 1. Parameters of each medium in this embodiment
[0059]
[0060] In this embodiment, according to Equation 1 and Table 1, the thermal resistance of the first heat-conducting medium 13 is 0.1 × 10⁻⁶. -3 / (3.7×10 -5 ×8)=0.33784, the thermal resistance of the heat sink 140 is 2.35×10 -3 / (0.5×10 -4 (×386)=0.12176, the thermal resistance of the heat transfer protrusion 142 is 1.5×10 -3 / (2.15×10 -4 ×386)=0.01807, and the thermal resistance of the second heat-conducting medium 15 is 0.5×10 -3 / (2.15×10 -4 ×8)=0.2907. Therefore, the total thermal resistance is 0.33784+0.12176+0.01807+0.2907=0.76837 K / W.
[0061] It should be noted that the thickness of the medium in Table 1 can be understood as part of the accompanying drawings (e.g., Figure 2 The dimension of the medium on the X-axis is given by the medium, and the area of the medium can be understood as the projected area of the medium on the first surface 110 of the substrate 11.
[0062] In a comparative example, the heat from the heat source is transferred to the heat-conducting shell through the heat-conducting medium and the boss. Therefore, the total thermal resistance is the sum of the thermal resistance of the heat-conducting medium and the thermal resistance of the boss. The boss protrudes from the heat-conducting shell. Therefore, the boss and the heat-conducting shell in the comparative example are made of the same material, both of which are zinc alloy.
[0063] Table 2. Parameters of each medium in the comparative examples
[0064]
[0065] The parameter descriptions for the media in Table 2 can be found in Table 1, and will not be repeated here.
[0066] In the comparative example, according to Equation 1 and Table 2, the thermal resistance of the heat-conducting medium is 0.4 × 10⁻⁶. -3 / (3.7×10 -5 ×8)=1.35136, the thermal resistance of the boss is 3×10 -3 / (3.7×10 -5 (×116)=0.69897. Therefore, the total thermal resistance is 2.05033 K / W.
[0067] Based on the total thermal resistance of the above embodiments and comparative examples, the total thermal resistance of the above embodiments is 0.76837 K / W, and the total thermal resistance of the comparative examples is 2.05033 K / W. Therefore, the total thermal resistance of the above embodiments is 0.76837 / 2.05033 times, or 37.5%, of the total thermal resistance of the comparative examples. Thus, by using the heat sink of this invention, a low total thermal resistance can be achieved, thereby exhibiting excellent heat dissipation efficiency.
[0068] Other embodiments will be listed below for illustration. It must be noted that the following embodiments use the component reference numerals and some content from the foregoing embodiments, with the same reference numerals representing the same or similar components, and descriptions of identical technical content omitted. For explanations of the omitted parts, please refer to the foregoing embodiments; these will not be repeated in the following embodiments.
[0069] Figure 6 This is a side sectional view of the optical module 1a according to another embodiment of the present invention, and Figure 7 for Figure 6 A schematic diagram of the projection of the heat dissipation section 140 of the optical module 1a and the heat source 12 onto the first surface 110 of the substrate 11.
[0070] According to one embodiment, the optical module 1a may include a heat-conducting housing 10, a substrate 11, a heat source 12, a first heat-conducting medium 13, a heat sink 14a, and a second heat-conducting medium 15.
[0071] In one embodiment, the difference between heat sink 14a and heat sink 14 is that heat sink 14a omits the heat transfer protrusion. In one embodiment, heat sink 14a may include a coupled heat dissipation portion 140 and two support portions 141. In one embodiment, heat source 12 may be located between substrate 11 and heat dissipation portion 140. In one embodiment, the two support portions 141 may protrude from the second surface 1400 and abut against substrate 11 to position heat dissipation portion 140 and heat source 12, thereby allowing the thickness of the first thermally conductive medium 13 to be sufficiently small, thereby reducing the thermal resistance of the first thermally conductive medium 13.
[0072] In one embodiment, the area of the projection P3 of the heat dissipation portion 140 onto the first surface 110 of the substrate 11 can be larger than the area P2 of the projection of the heat source 12 onto the first surface 110 of the substrate 11, thereby ensuring that the heat source 12 can make complete thermal contact with the heat dissipation portion 140. In another embodiment, the projected area of the heat dissipation portion 140 onto the first surface 110 of the substrate 11 can be 4 to 6 times the projected area of the heat source 12 onto the first surface 110 of the substrate 11.
[0073] In one embodiment, the heat from the heat source is transferred to the heat-conducting shell through the first heat-conducting medium 13, the heat dissipation part 140, and the second heat-conducting medium 15. Therefore, the total thermal resistance is the sum of the thermal resistance of the first heat-conducting medium 13, the thermal resistance of the heat dissipation part 140, and the thermal resistance of the second heat-conducting medium 15.
[0074] Table 3. Parameters of each medium in this embodiment
[0075]
[0076] The parameter descriptions for the media in Table 3 can be found in Table 1, and will not be repeated here.
[0077] In this embodiment, according to Equation 1 and Table 3, the thermal resistance of the first heat-conducting medium 13 is 0.1 × 10⁻⁶. -3 / (3.7×10 -5 ×8)=0.33784, the thermal resistance of the heat sink 140 is 2.35×10 -3 / (2.15×10 -4 ×386)=0.02831, and the thermal resistance of the second heat-conducting medium 15 is 0.5×10 -3 / (2.15×10 -4 ×8)=0.2907. Therefore, the total thermal resistance is 0.33784+0.02831+0.2907=0.65685 K / W.
[0078] As mentioned above, the total thermal resistance of the comparative example is 2.05033 K / W, and the calculation process of the total thermal resistance of the comparative example will not be repeated here.
[0079] Based on the total thermal resistance of the above embodiments and comparative examples, the total thermal resistance of the above embodiments is 0.65685 K / W, and the total thermal resistance of the comparative examples is 2.05033 K / W. Therefore, the total thermal resistance of the above embodiments is 0.65685 / 2.05033 times that of the comparative examples, i.e., 32.0%. Thus, by using the heat sink of this invention, a low total thermal resistance can be achieved, thereby exhibiting excellent heat dissipation efficiency.
[0080] In one embodiment, heat sink 14 or heat sink 14a may be selected depending on the component layout on substrate 11. Specifically, if a component is to be placed near a heat source that is in thermal contact with the heat sink, heat sink 14 may be used, because a receiving space for accommodating the component on substrate 11 can be formed between the heat dissipation portion 140 of heat sink 14 and substrate 11, but the present invention is not limited thereto.
[0081] In summary, the optical module disclosed in this embodiment of the present invention, by placing a heat sink with a higher thermal conductivity than the heat-conducting shell between a heat source (such as a high-power component) and the heat-conducting shell, allows the heat from the heat source to be effectively transferred to the heat-conducting shell for dissipation due to the low total thermal resistance. This achieves excellent heat dissipation efficiency, reduces the temperature rise of the heat source, and ensures the application reliability and ease of assembly of the optical module. Furthermore, since the heat-conducting shell does not directly contact the heat source, the problem of damage to the heat source due to impact is less likely to occur.
Claims
1. A light module including a heat sink, characterized in that, Include: A heat-conducting shell; A substrate is located inside the heat-conducting housing and has a first surface; A heat source is disposed on the first surface of the substrate; A first thermally conductive medium is disposed in the heat source, the heat source being located between the substrate and the first thermally conductive medium; A heat sink is disposed on the first heat-conducting medium; as well as A second heat-conducting medium is disposed on the heat sink, and the heat sink is thermally coupled to the heat-conducting shell through the second heat-conducting medium; The thermal conductivity of the heat sink is greater than that of the heat-conducting shell.
2. The optical module including a heat sink as described in claim 1, characterized in that, The heat sink includes a heat sink portion and two support portions coupled together. The heat source is located between the substrate and the heat sink portion. The heat sink portion has a second surface facing the substrate. The two support portions protrude from the second surface and abut against the substrate to position the heat sink portion and the heat source.
3. The optical module including a heat sink as described in claim 2, characterized in that, The projected area of the heat sink on the first surface of the substrate is 4 to 6 times the projected area of the heat source on the first surface of the substrate.
4. The optical module including a heat sink as described in claim 1, characterized in that, The heat sink includes a heat dissipation part, two support parts and a heat transfer protrusion. The heat source is located between the substrate and the heat transfer protrusion. The heat dissipation part has a second surface facing the substrate. The heat transfer protrusion protrudes from the second surface. The two support parts protrude from the second surface and abut against the substrate to position the heat transfer protrusion and the heat source.
5. The optical module including a heat sink as described in claim 4, characterized in that, The heat transfer protrusion, the heat dissipation part, and the two support parts are integrally formed.
6. The optical module including a heat sink as described in claim 4, characterized in that, The projected area of the heat transfer protrusion on the first surface of the substrate is greater than the projected area of the heat source on the first surface of the substrate.
7. The optical module including a heat sink as described in claim 1, characterized in that, The thickness of the second heat-conducting medium is greater than the thickness of the first heat-conducting medium.
8. The optical module including a heat sink as described in claim 1, characterized in that, The material of the first heat-conducting medium is the same as that of the second heat-conducting medium.
9. The optical module including a heat sink as described in claim 1, characterized in that, The heat-conducting housing is made of zinc alloy, and the heat sink is made of copper.
10. The optical module including a heat sink as described in claim 1, characterized in that, The thermally conductive housing includes a first thermally conductive housing component and a second thermally conductive housing component coupled together. The substrate is disposed on the first thermally conductive housing component, and the heat dissipation component is thermally coupled to the second thermally conductive housing component through the second thermally conductive medium.
11. The optical module including a heat sink as described in claim 10, characterized in that, This optical module is an eight-channel small pluggable optical module with a speed of over 800Gbps.
12. The optical module including a heat sink as described in claim 10, characterized in that, It further includes an external heat sink, wherein the second heat-conducting shell has two ridges, and the external heat sink is thermally coupled to the outer surface of the second heat-conducting shell and is located between the two ridges.
13. The optical module including a heat sink as described in claim 10, characterized in that, The heat source is a digital signal processor.