Optical module and optical communication system

Abstract

The optical module and the optical communication system provided by the application relate to the technical field of optical communication. The optical module comprises a shell, a PCB assembly and an optoelectronic device. The PCB assembly comprises at least two PCBs and at least one adapter plate. The at least two PCBs are arranged in a stacked manner, and the adapter plate is located between two adjacent PCBs and is electrically connected to the two PCBs respectively. The PCB assembly and the optoelectronic device are located in the shell respectively, and the optoelectronic device is electrically connected to at least one PCB. The optical module of the application can realize the up-down stacking of the two PCBs, has a simple structure, a low material cost and a simple manufacturing process, is conducive to the application of the double-plate PCB scheme in the optical module, and is conducive to the high-speed and miniaturization development of the optical module.

Description

Technical Field

[0001] This application relates to the field of optical communication technology, and in particular to an optical module and an optical communication system. Background Technology

[0002] The packaging standards for optical modules (such as QSFP28 and QSFP-DD) impose strict limitations on the overall size. However, the number of components that need to be integrated in high-speed modules has increased significantly (such as 400G modules containing DSP chips, 8-channel TIA / LA driver chips, power management units, optical engines, etc.). The layout space of a single PCB (printed circuit board) is already saturated. Therefore, it is necessary to use two PCBs stacked one on top of the other to achieve "three-dimensional expansion" of the internal space of the optical module.

[0003] In related technologies, the upper and lower PCBs are typically used as follows: Figure 1 The rigid-flex PCB shown here is a flexible connection between two PCBs via an FPC section, allowing the two PCBs to be stacked one on top of the other. However, this type of rigid-flex PCB is not only expensive in terms of materials and complex in terms of manufacturing process, but also has low wiring density, which limits the application of the dual PCB solution in optical modules. Utility Model Content

[0004] This application provides an optical module and an optical communication system that can solve the technical problems existing in related technologies.

[0005] Specifically, the technical solution is as follows.

[0006] On the one hand, an optical module is provided, the optical module comprising: a housing, a PCB assembly, and optoelectronic devices;

[0007] The PCB assembly includes at least two PCBs and at least one adapter board. The at least two PCBs are stacked together, and the adapter board is located between two adjacent PCBs and is electrically connected to each of the two PCBs.

[0008] The PCB assembly and the optoelectronic device are respectively located within the housing, and the optoelectronic device is electrically connected to at least one of the PCBs.

[0009] The optical module of this application comprises a PCB assembly consisting of at least two PCBs and at least one adapter board. Adjacent PCBs can be physically connected through the adapter board. The adapter board can not only fix two adjacent PCBs together, but also realize electrical connection between the two PCBs, enabling the two PCBs to be stacked vertically. The structure is simple, the material cost is low, and the manufacturing process is simple, which is conducive to the application of dual-PCB solutions in optical modules, and thus conducive to the development of high-speed and miniaturized optical modules.

[0010] In some embodiments, each of the PCBs is provided with conductive lines, and the conductive lines on two adjacent PCBs are electrically connected through the adapter board;

[0011] Each of the PCBs is provided with at least one electronic component, and the at least one electronic component is electrically connected to the conductive line.

[0012] With the above arrangement, electronic components on one PCB can be electrically connected to electronic components on another PCB through conductive lines and an adapter board.

[0013] In some embodiments, the adapter board has at least one conductive connection structure on its first and second surfaces along the thickness direction, the at least one conductive connection structure on the first surface being electrically connected to the conductive lines on the first PCB, and the at least one conductive connection structure on the second surface being electrically connected to the conductive lines on the second PCB.

[0014] With the above arrangement, the adapter board can be connected to the conductive lines on the first PCB and the second PCB respectively through the conductive connection structures on the first surface and the second surface, wherein the first PCB and the second PCB are two PCBs on both sides of the adapter board.

[0015] In some embodiments, the adapter plate is provided with at least one metal through hole, which is arranged through the thickness direction, and the at least one conductive connection structure on the first surface and the at least one conductive connection structure on the second surface are electrically connected through the at least one metal through hole.

[0016] With the above arrangement, the first conductive structures on the first and second surfaces of the adapter board can be electrically connected through metal through-holes, thereby realizing the electrical connection between the first PCB and the second PCB.

[0017] In some embodiments, the conductive connection structure includes a first pad, and the PCB surface facing the adapter board has metal contacts, wherein the first pad and the metal contacts are soldered together.

[0018] With the above arrangement, the first pad is used as the conductive connection structure, which can be soldered to the metal contacts on the PCB. The adapter board is connected to the PCB through LGA (land grid array) technology.

[0019] In some embodiments, the conductive connection structure includes solder balls, and the PCB surface facing the adapter board is provided with a second pad, the solder balls being soldered to the second pad.

[0020] With the above arrangement, solder balls are used as conductive connection structures, which can be soldered to the second pad on the PCB. The adapter board is connected to the PCB through BGA (ball grid array) packaging technology.

[0021] In some embodiments, at least one adapter board is provided with a reference identification mark.

[0022] In this embodiment, during processing, the processing equipment can achieve micron-level alignment by recognizing the reference identification mark, avoiding structural misalignment between the adapter board and the PCB. During inspection and sorting, the reference identification mark serves as the identity and location identifier of the adapter board, helping the equipment quickly identify the adapter board and select good products. During application and installation, when the adapter board is mounted to the PCB, the pick-and-place machine can use the reference identification mark as a reference to ensure precise contact between the adapter board and the PCB pads, guaranteeing reliable electrical connections.

[0023] In some embodiments, the adapter board has a clearance area for avoiding electronic components on the PCB surface.

[0024] With the above arrangement, an avoidance area is arranged on the adapter board. This avoidance area can be formed by removing part of the structure of the adapter board. When the adapter board is connected to the PCB, the position of the electronic components coincides with the position of the avoidance area. At least part of the electronic components can extend into the avoidance area, thereby reducing the occupancy of the adapter board on the PCB surface and improving the utilization rate of the PCB surface.

[0025] In some embodiments, the adapter plate is a frame structure.

[0026] With the above arrangement, the adapter board is constructed as a frame structure. The adapter board can be connected to two PCBs respectively using this frame structure. A hole is cut in the middle of the frame structure to avoid obstructing electronic components on the PCB surface. The frame structure provides better structural stability and stable and reliable support for both PCBs.

[0027] In some embodiments, the adapter plate is provided with at least two metal through holes, which are respectively arranged on two opposite side frames of the enclosure structure.

[0028] When the adapter board has a frame structure, at least two metal through holes in the adapter board can be arranged on two opposite sides of the frame structure, which helps to reduce the processing difficulty of the metal through holes and improves the connection efficiency between the adapter board and the PCB.

[0029] In some embodiments, gold fingers are provided at the end of one of the at least two PCBs.

[0030] With the above arrangement, the optical module can be plugged into the slot of the optical communication equipment using the gold fingers to form a low-impedance circuit path, ensuring the electrical connection between the optical module and equipment such as switches and servers.

[0031] In some embodiments, the gold fingers extend from the ends of other PCBs.

[0032] With the above arrangement, the optical module will not be interfered with by the ends of other PCBs when it is plugged into the slot of the optical communication equipment using the gold fingers.

[0033] On the other hand, an optical communication system is provided, which includes the optical module described in this application.

[0034] The optical communication system of this application uses the optical module of this application and has all the beneficial technical effects of this application. Since the optical module uses PCB components with lower cost and simpler manufacturing process, it is possible to use double-layer or multi-layer PCB components in the optical module. The internal space of the optical module is three-dimensionally expanded, which can accommodate more components. This makes the development of the optical module less restricted by the internal space size. The optical module can meet the needs of higher speed scenarios, and the optical communication system can achieve higher transmission rates. Attached Figure Description

[0035] Figure 1 This is a structural diagram of a rigid-flex PCB provided by related technologies;

[0036] Figure 2 This is an exploded view of the optical module provided in the embodiments of this application;

[0037] Figure 3 This is an exploded view of the PCB assembly provided in the embodiments of this application;

[0038] Figure 4 This is a structural cross-sectional view of the PCB assembly provided in the embodiments of this application;

[0039] Figure 5 This is a structural cross-sectional view of a PCB assembly provided in another embodiment of this application;

[0040] Figure 6 This is a structural cross-sectional view of a PCB assembly provided in another embodiment of this application.

[0041] The reference numerals in the attached figures represent:

[0042] 1. Shell;

[0043] 11. First shell; 12. Second shell;

[0044] 2. PCB assembly;

[0045] 21. PCB; 21a. First PCB; 21b. First PCB; 211. Conductive circuit; 212. Electronic component; 213. Metal contact; 214. Second pad; 215. Pinhole socket; 216. Gold finger;

[0046] 22. Adapter board; 22a. First surface; 22b. Second surface; 221. Conductive connection structure; 2211. First pad; 2212. Solder ball; 2213. Metal pin; 222. Metal through hole; 223. Reference identification mark; 224. Avoidance area;

[0047] 3. Optoelectronic devices;

[0048] 31. Transmitting optical devices; 32. Receiving optical devices. Detailed Implementation

[0049] On the one hand, combined with Figure 2 and Figure 3 As shown, this embodiment provides an optical module, which includes: a housing 1, a PCB assembly 2, and optoelectronic devices 3.

[0050] The PCB assembly 2 includes at least two PCBs 21 and at least one adapter board 22. The at least two PCBs 21 are stacked together, and the adapter board 22 is located between two adjacent PCBs 21 and is electrically connected to each of the two PCBs 21.

[0051] PCB assembly 2 and optoelectronic device 3 are located inside housing 1, and optoelectronic device 3 is electrically connected to at least one PCB 21.

[0052] In this embodiment, the optical module PCB assembly 2 is composed of at least two PCBs 21 and at least one adapter board 22. Adjacent PCBs 21 can be physically connected through the adapter board 22. The adapter board 22 can not only fix two adjacent PCBs 21 together, but also realize the electrical connection between the two PCBs 21, enabling the two PCBs 21 to be stacked one on top of the other. The structure is simple, the material cost is low, and the manufacturing process is simple, which is conducive to the application of the dual-PCB 21 solution in optical modules, and thus conducive to the development of high-speed and miniaturized optical modules.

[0053] In some possible implementations, the housing 1 includes a first housing 111 and a second housing 121, which are fastened together to form a receiving cavity that can accommodate the PCB assembly 2 and the optoelectronic device 3.

[0054] In some possible implementations, the number of PCBs 21 can be two, three, etc. Among these PCBs 21, only two can be stacked vertically adjacent to each other and connected by an adapter board 22, or all PCBs 21 can be stacked vertically in sequence, with an adapter board 22 between each pair of PCBs 21 to connect the two adjacent PCBs 21.

[0055] In some possible implementations, PCB21 can be a single-sided board (with conductive patterns on only one side, low cost, suitable for simple circuits), a double-sided board (with conductive layers on both sides, interconnected by metal vias), or a multilayer board (3 or more layers, using inner layer lamination process, suitable for high-speed, complex circuits).

[0056] For example, when PCB21 is a multilayer board, an insulating substrate must be selected, along with copper foil as the conductive layer material. The inner layer copper foil presents the designed circuit pattern through "pattern transfer" (coating photoresist → exposure → development), and then excess copper foil is removed by etching to form the inner layer signal / power / ground pattern. Afterwards, according to the designed stacking order, the inner layer board, prepreg (insulating adhesive material), and outer layer copper foil are stacked sequentially. After precise alignment, it is placed in a laminator and subjected to high temperature (170-180℃) and high pressure (20-40 kg / cm²). 2 The layers are pressed together, and after the prepreg melts and solidifies, they are permanently bonded together to form a single substrate. Next, holes (including through-holes, blind vias, or buried vias) are drilled into the substrate for interlayer electrical connections. A thin copper layer is deposited on the hole walls using a "plated copper" process (chemical copper plating) to form conductive channels. Using a pattern transfer and etching process similar to that used for the inner layers, the desired circuit patterns are fabricated on the outer copper foil of the substrate.

[0057] In some possible implementations, the adapter board 22 is made of the same insulating substrate as the PCB 21 board.

[0058] Among some possible implementations, refer to Figure 2 As shown, the optoelectronic device 3 includes a transmitting optical device 31 and a receiving optical device 32. The transmitting optical device 31 is used to receive the electrical drive signal output by the PCB21, generate an optical signal and couple it into the optical fiber. The receiving optical device 32 is used to receive the optical signal transmitted through the optical fiber, convert it into an electrical signal and transmit it to the PCB21.

[0059] For example, the transmitting optical device 31 and the receiving optical device 32 can be electrically connected to the PCB 21 through flexible circuit boards and board connectors, respectively.

[0060] Combination Figure 4 , Figure 5 and Figure 6As shown, in some embodiments, each PCB21 is provided with a conductive line 211, and the conductive lines 211 on two adjacent PCBs21 are electrically connected through an adapter board 22.

[0061] Each PCB21 is provided with at least one electronic component 212, and at least one electronic component 212 is electrically connected to the conductive line 211.

[0062] With the above arrangement, an electronic component 212 on one PCB21 can be electrically connected to an electronic component 212 on another PCB21 through a conductive line 211 and an adapter board 22.

[0063] In some possible implementations, electronic components 212 include driving and amplifying devices, such as laser drivers, transimpedance amplifiers, limiting amplifiers, clock data recovery chips, etc.; power management and protection devices, such as linear regulators, DC-DC converters, fuses, etc.; signal processing and connection devices, such as microcontrollers, equalizers, clock generators, etc.; and connection devices, such as indicator lights, resistors, inductors, etc.

[0064] Combination Figure 4 , Figure 5 and Figure 6 As shown, in some embodiments, the first surface 22a and the second surface 22b of the adapter plate 22 along the thickness direction are respectively provided with at least one conductive connection structure 221. The at least one conductive connection structure 221 on the first surface 22a is electrically connected to the conductive line 211 on the first PCB 21a, and the at least one conductive connection structure 221 on the second surface 22b is electrically connected to the conductive line 211 on the second PCB 21b.

[0065] With the above arrangement, the adapter board 22 can be connected to the conductive lines 211 on the first PCB 21a and the second PCB 21b respectively through the conductive connection structure 221 on the first surface 22a and the second surface 22b, wherein the first PCB 21a and the second PCB 21b are two PCBs 21 on both sides of the adapter board 22.

[0066] In some possible implementations, the number of conductive connection structures 221 on the first surface 22a is multiple, and the multiple conductive connection structures 221 are arranged in an array. The number of conductive connection structures 221 on the second surface 22b is also multiple, and the multiple conductive connection structures 221 are arranged in an array.

[0067] The number of first conductive structures on the first surface 22a and the number of first conductive structures on the second surface 22b can be the same, and their positions are axially aligned in a one-to-one correspondence.

[0068] Combination Figure 4 , Figure 5 and Figure 6 As shown, in some embodiments, the adapter plate 22 is provided with at least one metal through hole 222, which is arranged through the thickness direction. At least one conductive connection structure 221 on the first surface 22a and at least one conductive connection structure 221 on the second surface 22b are electrically connected through at least one metal through hole 222.

[0069] With the above arrangement, the first conductive structures on the first surface 22a and the second surface 22b of the adapter board 22 can be electrically connected through the metal through-hole 222, thereby realizing the electrical connection between the first PCB 21a and the second PCB 21b.

[0070] In some possible implementations, the metal via 222 includes a cylindrical hole extending through the thickness of the adapter plate 22 on the first surface 22a and the second surface 22b, and achieves conductivity by metallizing the hole walls or directly filling them with metal.

[0071] For example, the metal through hole 222 is a plated through hole (PTH), in which a conductive layer is formed on the hole wall by chemical copper plating or electroplating to realize multi-layer circuit interconnection.

[0072] The conductive layer deposited on the pore walls can be 18-35μm thick, but needs to be thickened to 70μm for high-frequency applications.

[0073] Combination Figure 4 As shown, in some embodiments, the conductive connection structure 221 includes a first pad 2211, and the surface of the PCB 21 facing the adapter board 22 is provided with a metal contact 213, and the first pad 2211 and the metal contact 213 are soldered together.

[0074] With the above arrangement, the first pad 2211 is used as the conductive connection structure 221, which can be soldered to the metal contact 213 on the PCB 21. The adapter board 22 is connected to the PCB 21 through LGA (land grid array) technology.

[0075] Combination Figure 5 As shown, in some embodiments, the conductive connection structure 221 includes solder balls 2212, and a second pad 214 is provided on the surface of the PCB 21 facing the adapter board 22, and the solder balls 2212 are soldered to the second pad 214.

[0076] With the above arrangement, solder balls 2212 are used as conductive connection structures 221, which can be soldered to the second pad 214 on the PCB 21. The adapter board 22 is connected to the PCB 21 through BGA (ball grid array) packaging technology.

[0077] Combination Figure 6 As shown, in some embodiments, the conductive connection structure 221 includes a metal pin 2213, and a pinhole socket 215 is provided on the surface of the PCB 21 facing the adapter board 22, and the metal pin 2213 is plugged into the pinhole socket 215.

[0078] With the above arrangement, metal pins 2213 are used as conductive connection structures 221, which can be plugged into and connected to pin sockets 215 on PCB 21. The adapter board 22 is connected to PCB 21 through PGA (pin grid array) technology.

[0079] Combination Figure 3 As shown, in some embodiments, at least one adapter board 22 is provided with a reference identification mark 223.

[0080] In this embodiment, during processing, the processing equipment can achieve micron-level alignment by recognizing the reference identification mark 223, avoiding structural misalignment between the adapter board 22 and the PCB 21. During inspection and sorting, the reference identification mark 223 can serve as the identity and location identifier of the adapter board 22, helping the equipment to quickly identify the adapter board 22 and select good products. During application and installation, when the adapter board 22 is mounted on the PCB 21, the pick-and-place machine can use the reference identification mark 223 as a reference to ensure precise contact between the pads of the adapter board 22 and the PCB 21, ensuring reliable electrical connections.

[0081] In some possible implementations, the number of reference identification tags 223 can be one, two, three, four, etc. For example, the number of reference identification tags 223 is three or more.

[0082] The shape of the reference identification mark 223 can be circular, square, triangular, or cross-shaped.

[0083] Combination Figure 3 As shown, in some embodiments, the adapter board 22 is provided with a clearance area 224, which is used to avoid electronic components 212 on the surface of the PCB 21.

[0084] With the above arrangement, an avoidance area 224 is arranged on the adapter board 22. The avoidance area 224 can be formed by removing part of the structure of the adapter board 22. When the adapter board 22 is connected to the PCB 21, the position of the electronic component 212 coincides with the position of the avoidance area 224. At least part of the electronic component 212 can extend into the avoidance area 224, thereby reducing the occupation of the adapter board 22 on the surface of the PCB 21 and improving the utilization rate of the PCB 21 surface.

[0085] Combination Figure 3 As shown, in some embodiments, the adapter plate 22 is a frame structure.

[0086] With the above arrangement, the adapter board 22 is constructed as a frame structure. The adapter board 22 can be connected to two PCBs 21 respectively using the frame structure. The frame structure has a hole in the middle to avoid the electronic components 212 on the surface of the PCBs 21. The frame structure has better structural stability and can provide stable and reliable support for the two PCBs 21.

[0087] In some possible implementations, the frame structure can be polygonal, circular, etc.

[0088] For example, the shape of the frame structure is quadrilateral, such as a square, trapezoid, rectangle, etc.

[0089] Combination Figure 3 As shown, in some embodiments, the adapter plate 22 is provided with at least two metal through holes 222, which are respectively arranged on two opposite side frames of the frame structure.

[0090] In this embodiment, when the adapter plate 22 is a frame structure, at least two metal through holes 222 in the adapter plate 22 can be arranged on two opposite sides of the frame structure, which helps to reduce the processing difficulty of the metal through holes 222 and improves the connection efficiency between the adapter plate 22 and the PCB 21.

[0091] Combination Figure 3 As shown, in some embodiments, a gold finger 216 is provided at the end position of one of the at least two PCBs 21.

[0092] With the above arrangement, the optical module can be plugged into the slot of the optical communication equipment using the gold finger 216 to form a low impedance circuit path, ensuring the electrical connection between the optical module and equipment such as switches and servers.

[0093] In some possible implementations, the gold finger 216 is located at the front end of the optical module and can be plugged into and connected to optical communication equipment (routers, switches, servers, etc.). The rear end of the optical module has a fiber optic interface for connecting to optical fibers. The fiber optic interface can include a transmitter interface and a receiver interface. The transmitter interface is connected to the transmitter optical device 31 and is used to inject the optical signal output by the transmitter optical device 31 into the optical fiber. The receiver optical device 32 is connected to the receiver optical device 32 and is used to transmit the optical signal from the input optical signal to the receiver optical device 32.

[0094] Combination Figure 3 As shown, in some embodiments, the gold finger 216 extends beyond the end of the other PCB 21.

[0095] With the above arrangement, when the optical module is plugged into the slot of the optical communication equipment using the gold finger 216, it will not be interfered with by the ends of other PCBs 21.

[0096] For example, the gold finger 216 extends from the end of the other PCB 21 facing the front end of the optical module.

[0097] On the other hand, this embodiment provides an optical communication system, which includes the optical module of this application.

[0098] The optical communication system of this embodiment uses the optical module of this application and has all the beneficial technical effects of this application. Since the optical module uses a PCB component 2 with lower cost and simpler manufacturing process, it is possible to use double-layer or multi-layer PCB components 2 in the optical module. The internal space of the optical module is three-dimensionally expanded, which can accommodate more components. This makes the development of the optical module less restricted by the internal space size. The optical module can meet the needs of higher speed scenarios, and the optical communication system can achieve a higher transmission rate.

[0099] The optical module can receive electrical signals (such as digital signals represented by high and low levels) from devices like routers, switches, and servers, convert them into optical signals (lasers of different wavelengths, such as 850nm, 1310nm, and 1550nm), and then transmit the optical signals through the fiber optic interface into the optical fiber. It can also receive optical signals transmitted from the optical fiber, convert them into weak electrical signals, and output standard electrical signals that the devices can recognize, which are then transmitted back to routers, servers, and other optical communication equipment.

[0100] The above description is only for the purpose of enabling those skilled in the art to understand the technical solution of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the principles of this application should be included within the protection scope of this application.

Claims

1. An optical module, characterized in that, The optical module includes: a housing (1), a PCB assembly (2), and optoelectronic devices (3); The PCB assembly (2) includes at least two PCBs (21) and at least one adapter board (22). The at least two PCBs (21) are stacked together, and the adapter board (22) is located between two adjacent PCBs (21) and is electrically connected to the two PCBs (21) respectively. The PCB assembly (2) and the optoelectronic device (3) are respectively located inside the housing (1), and the optoelectronic device (3) is electrically connected to at least one of the PCBs (21).

2. The optical module according to claim 1, characterized in that, Each of the PCBs (21) is provided with a conductive line (211), and the conductive lines (211) on two adjacent PCBs (21) are electrically connected through the adapter plate (22); Each of the PCBs (21) is provided with at least one electronic component (212), and the at least one electronic component (212) is electrically connected to the conductive line (211).

3. The optical module according to claim 2, characterized in that, The adapter plate (22) has at least one conductive connection structure (221) on its first surface (22a) and second surface (22b) along the thickness direction. The at least one conductive connection structure (221) on the first surface (22a) is electrically connected to the conductive line (211) on the first PCB (21a), and the at least one conductive connection structure (221) on the second surface (22b) is electrically connected to the conductive line (211) on the second PCB (21b).

4. The optical module according to claim 3, characterized in that, The adapter plate (22) is provided with at least one metal through hole (222), which is arranged through the thickness direction. The at least one conductive connection structure (221) on the first surface (22a) and the at least one conductive connection structure (221) on the second surface (22b) are electrically connected through the at least one metal through hole (222).

5. The optical module according to claim 4, characterized in that, The conductive connection structure (221) includes a first pad (2211), and the PCB (21) has a metal contact (213) on its surface facing the adapter board (22). The first pad (2211) and the metal contact (213) are soldered together.

6. The optical module according to claim 4, characterized in that, The conductive connection structure (221) includes solder balls (2212), and the PCB (21) has a second pad (214) on the surface facing the adapter board (22), and the solder balls (2212) are soldered to the second pad (214).

7. The optical module according to claim 1, characterized in that, At least one adapter plate (22) is provided with a reference identification mark (223).

8. The optical module according to any one of claims 1 to 7, characterized in that, The adapter board (22) is provided with a clearance area (224), which is used to avoid electronic components (212) on the surface of the PCB (21).

9. The optical module according to any one of claims 1 to 7, characterized in that, The adapter plate (22) is a frame structure.

10. The optical module according to claim 9, characterized in that, The adapter plate (22) is provided with at least two metal through holes (222), which are respectively arranged on two opposite side frames of the frame structure.

11. The optical module according to any one of claims 1 to 7, characterized in that, A gold finger (216) is provided at the end position of one of the at least two PCBs (21).

12. The optical module according to claim 11, characterized in that, The gold finger (216) extends from the end of the other PCB (21).

13. An optical communication system, characterized in that, The optical communication system includes the optical module according to any one of claims 1 to 12.

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