CN214540156U

CN214540156U - Optical module

Info

Publication number: CN214540156U
Application number: CN202121054948.7U
Authority: CN
Inventors: 郑龙; 董玉婷; 郝世聪; 杨思更
Original assignee: Hisense Broadband Multimedia Technology Co Ltd
Current assignee: Hisense Broadband Multimedia Technology Co Ltd
Priority date: 2021-05-17
Filing date: 2021-05-17
Publication date: 2021-10-29
Anticipated expiration: 2031-05-17

Abstract

The optical module provided by the application comprises a circuit board, wherein a through hole is formed in the circuit board, a metal heat sink is embedded in the through hole, a laser component and a silicon optical chip are arranged on the metal heat sink, a first supporting table surface and a second supporting table surface are respectively arranged at two ends of the metal heat sink and are used for supporting the circuit board, a first metal layer is arranged on the lower surface of the circuit board at the contact area with the upper surface of the first supporting table surface, a second metal layer is arranged on the lower surface of the circuit board at the contact area with the upper surface of the second supporting table surface, the first supporting table surface is electrically connected with the first metal layer, the second supporting table surface is electrically connected with the second metal layer, the first metal layer and the second metal layer are electrically connected with a grounding layer of the circuit board, and the first supporting table surface and the second supporting table surface are electrically connected with corresponding metal layers, so that the ground connection of the metal heat sink can be realized, the silicon optical chip is attached to the metal heat sink to realize the grounding connection of the silicon optical chip.

Description

Optical module

Technical Field

The application relates to the technical field of optical communication, in particular to an optical module.

Background

The optical communication technology can be applied to novel services and application modes such as cloud computing, mobile internet, video and the like. In optical communication, an optical module is a tool for realizing the interconversion of optical signals and is one of the key devices in optical communication equipment. The adoption of a silicon optical chip to realize a photoelectric conversion function has become a mainstream scheme adopted by a high-speed optical module.

In the silicon optical module, a silicon optical chip is arranged on a circuit board and connected to a grounding area of the circuit board through a gold wire to realize the grounding connection of the silicon optical chip, but the gold wire can introduce parasitic inductance and reduce the signal transmission quality, so another silicon optical chip grounding mode needs to be provided.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides an optical module to provide another silicon optical chip grounding mode.

A circuit board having a through hole;

the metal heat sink is embedded in the through hole, a first supporting table surface and a second supporting table surface are respectively arranged at two ends of the metal heat sink, and the first supporting table surface and the second supporting table surface are used for supporting the circuit board;

a first metal layer is arranged on the lower surface of the circuit board at the contact area with the upper surface of the first supporting table surface, a second metal layer is arranged on the lower surface of the circuit board at the contact area with the upper surface of the second supporting table surface, the first supporting table surface is electrically connected with the first metal layer, the second supporting table surface is electrically connected with the second metal layer, and the first metal layer and the second metal layer are respectively electrically connected with the grounding layer of the circuit board so as to realize the grounding of the metal heat sink;

the laser assembly is attached to the metal heat sink and used for emitting light which does not carry signals;

and the silicon optical chip is attached to the metal heat sink and used for receiving the light which is emitted by the laser assembly and does not carry signals, and the grounding of the silicon optical chip is realized through the grounding of the metal heat sink.

Has the advantages that: the optical module provided by the application comprises a circuit board, wherein a through hole is formed in the circuit board, a metal heat sink is embedded in the through hole, a laser component and a silicon optical chip are arranged on the metal heat sink, a first supporting table surface and a second supporting table surface are respectively arranged at two ends of the metal heat sink and are used for supporting the circuit board, a first metal layer is arranged on the lower surface of the circuit board at the contact area with the upper surface of the first supporting table surface, a second metal layer is arranged on the lower surface of the circuit board at the contact area with the upper surface of the second supporting table surface, the first supporting table surface is electrically connected with the first metal layer, the second supporting table surface is electrically connected with the second metal layer, the first metal layer and the second metal layer are electrically connected with a grounding layer of the circuit board, and the first supporting table surface and the second supporting table surface are electrically connected with corresponding metal layers, so that the ground connection of the metal heat sink can be realized, because the silicon optical chip is attached to the metal heat sink, the grounding connection of the silicon optical chip can be realized, so that the normal work of the silicon optical chip is ensured, the parasitic inductance caused by the fact that the silicon optical chip is connected to the ground through a gold thread in the prior art is avoided, and the quality of signal transmission is ensured.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic diagram of a connection relationship of an optical communication terminal;

FIG. 2 is a schematic diagram of an optical network unit;

fig. 3 is a schematic structural diagram of an optical module according to an embodiment of the present disclosure;

FIG. 4 is a schematic diagram of an exploded structure of an optical module according to an embodiment of the present application;

fig. 5 is a schematic front structure diagram of a circuit board according to an embodiment of the present disclosure;

fig. 6 is a schematic structural diagram of a circuit board provided in the embodiment of the present application with a protective cover removed;

fig. 7 is an exploded view of a circuit board and various structures on the surface thereof according to an embodiment of the present disclosure;

fig. 8 is a first schematic structural diagram of a metal heat sink provided in an embodiment of the present application;

fig. 9 is a schematic structural diagram of a metal heat sink according to an embodiment of the present application;

fig. 10 is an overall schematic diagram of various structures of a metal heat sink surface according to an embodiment of the present application;

fig. 11 is an exploded schematic view of various structures on the surface of a metal heat sink according to an embodiment of the present disclosure;

fig. 12 is a schematic diagram of a metal heat sink embedded in a circuit board in a top view according to an embodiment of the present application;

fig. 13 is a schematic diagram of a metal heat sink embedded in a circuit board according to an embodiment of the present disclosure from a side view;

fig. 14 is a schematic diagram illustrating a metal heat sink according to an embodiment of the present application exploded from a circuit board;

fig. 15 is a schematic cross-sectional view of a metal heat sink embedded in a circuit board according to an embodiment of the present disclosure;

fig. 16 is a schematic top view of a metal heat sink provided in an embodiment of the present application;

fig. 17 is a schematic structural diagram of a metal layer laid on the periphery of a through hole according to an embodiment of the present application;

fig. 18 is a schematic diagram of a relative position relationship between a metal heat sink setting support surface and a metal layer laid on the periphery of a through hole according to an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

One of the core links of optical fiber communication is the interconversion of optical and electrical signals. The optical fiber communication uses optical signals carrying information to transmit in information transmission equipment such as optical fibers/optical waveguides, and the information transmission with low cost and low loss can be realized by using the passive transmission characteristic of light in the optical fibers/optical waveguides; meanwhile, the information processing device such as a computer uses an electric signal, and in order to establish information connection between the information transmission device such as an optical fiber or an optical waveguide and the information processing device such as a computer, it is necessary to perform interconversion between the electric signal and the optical signal.

The optical module realizes the function of interconversion of optical signals and electrical signals in the technical field of optical fiber communication, and the interconversion of the optical signals and the electrical signals is the core function of the optical module. The optical module is electrically connected with an external upper computer through a golden finger on an internal circuit board of the optical module, and the main electrical connection comprises power supply, I2C signals, data signals, grounding and the like; the electrical connection mode realized by the gold finger has become the mainstream connection mode of the optical module industry, and on the basis of the mainstream connection mode, the definition of the pin on the gold finger forms various industry protocols/specifications.

Fig. 1 is a schematic diagram of connection relationship of an optical communication terminal. As shown in fig. 1, the connection of the optical communication terminal mainly includes the interconnection among the optical network terminal 100, the optical module 200, the optical fiber 101 and the network cable 103;

one end of the optical fiber 101 is connected with a far-end server, one end of the network cable 103 is connected with local information processing equipment, and the connection between the local information processing equipment and the far-end server is completed by the connection between the optical fiber 101 and the network cable 103; and the connection between the optical fiber 101 and the network cable 103 is made by the optical network terminal 100 having the optical module 200.

An optical port of the optical module 200 is externally accessed to the optical fiber 101, and establishes bidirectional optical signal connection with the optical fiber 101; an electrical port of the optical module 200 is externally connected to the optical network terminal 100, and establishes bidirectional electrical signal connection with the optical network terminal 100; the optical module realizes the interconversion of optical signals and electric signals, thereby realizing the establishment of information connection between the optical fiber and the optical network terminal; specifically, the optical signal from the optical fiber is converted into an electrical signal by the optical module and then input to the optical network terminal 100, and the electrical signal from the optical network terminal 100 is converted into an optical signal by the optical module and input to the optical fiber.

The optical network terminal is provided with an optical module interface 102, which is used for accessing an optical module 200 and establishing bidirectional electric signal connection with the optical module 200; the optical network terminal is provided with a network cable interface 104, which is used for accessing the network cable 103 and establishing bidirectional electric signal connection with the network cable 103; the optical module 200 is connected to the network cable 103 through the optical network terminal 100, specifically, the optical network terminal transmits a signal from the optical module to the network cable and transmits the signal from the network cable to the optical module, and the optical network terminal serves as an upper computer of the optical module to monitor the operation of the optical module.

At this point, a bidirectional signal transmission channel is established between the remote server and the local information processing device through the optical fiber, the optical module, the optical network terminal and the network cable.

Common information processing apparatuses include routers, switches, electronic computers, and the like; the optical network terminal is an upper computer of the optical module, provides data signals for the optical module, and receives the data signals from the optical module, and the common upper computer of the optical module also comprises an optical line terminal and the like.

Fig. 2 is a schematic diagram of an optical network terminal structure. As shown in fig. 2, the optical network terminal 100 has a circuit board 105, and a cage 106 is disposed on a surface of the circuit board 105; an electric connector is arranged in the cage 106 and used for connecting an electric port of an optical module such as a golden finger; the cage 106 is provided with a heat sink 107, and the heat sink 107 has a projection such as a fin that increases a heat radiation area.

The optical module 200 is inserted into the optical network terminal, specifically, the electrical port of the optical module is inserted into the electrical connector inside the cage 106, and the optical port of the optical module is connected to the optical fiber 101.

The cage 106 is positioned on the circuit board, and the electrical connector on the circuit board is wrapped in the cage, so that the electrical connector is arranged in the cage; the optical module is inserted into the cage, held by the cage, and the heat generated by the optical module is conducted to the cage 106 and then diffused by the heat sink 107 on the cage.

Fig. 3 is a schematic diagram of an optical module according to an embodiment of the present invention, and fig. 4 is a schematic diagram of an optical module according to an embodiment of the present invention. As shown in fig. 3 and 4, an optical module 200 provided by an embodiment of the present invention includes an upper housing 201, a lower housing 202, an unlocking member, a circuit board 203, a protective cover 300, an optical fiber receptacle 400, and an optical fiber ribbon 401. Wherein, devices such as a silicon optical chip, a laser component and the like are arranged below the protective cover 300.

The upper case 201 and the lower case 202 form a case having a packing cavity. Specifically, the upper shell 201 is covered on the lower shell 202 to form a package cavity with two openings; the outer contour of the wrapping cavity is generally a square body, and specifically, the lower shell comprises a main plate and two side plates which are positioned at two sides of the main plate and are perpendicular to the main plate; the upper shell comprises a cover plate, and the cover plate covers two side plates of the upper shell to form a wrapping cavity; the upper shell can also comprise two side walls which are positioned at two sides of the cover plate and are perpendicular to the cover plate, and the two side walls are combined with the two side plates to realize that the upper shell covers the lower shell. Optionally, fins are arranged on the upper shell 201, and the upper computer is combined to assist in heat dissipation of the optical module.

The two openings may be two ends (204, 205) in the same direction, or two openings in different directions; one opening is an electric port 204, and a gold finger of the circuit board extends out of the electric port 204 and is inserted into an upper computer such as an optical network terminal; the other opening is an optical port 205 for external optical fiber access to connect with a silicon optical chip inside the optical module; the photoelectric devices such as the circuit board 203, the protective cover 300, the silicon optical chip, the laser assembly and the like are positioned in the packaging cavity.

The assembly mode of combining the upper shell and the lower shell is adopted, so that the circuit board 203, the protective cover 300 and the silicon optical chip and other devices can be conveniently installed in the shell, and the upper shell and the lower shell form the outermost packaging protective shell of the optical module; the upper shell and the lower shell are made of metal materials generally, so that electromagnetic shielding and heat dissipation are facilitated; generally, the housing of the optical module is not made into an integrated component, so that when devices such as a circuit board and the like are assembled, the positioning component, the heat dissipation component and the electromagnetic shielding component cannot be installed, and the production automation is not facilitated.

The unlocking component is located on the outer wall of the wrapping cavity/lower shell 202 and used for realizing the fixed connection between the optical module and the upper computer or releasing the fixed connection between the optical module and the upper computer.

The unlocking component is provided with a clamping component matched with the upper computer cage; the end of the unlocking component can be pulled to enable the unlocking component to move relatively on the surface of the outer wall; the optical module is inserted into a cage of the upper computer, and the optical module is fixed in the cage of the upper computer by a clamping component of the unlocking component; by pulling the unlocking component, the clamping component of the unlocking component moves along with the unlocking component, so that the connection relation between the clamping component and the upper computer is changed, the clamping relation between the optical module and the upper computer is released, and the optical module can be drawn out from the cage of the upper computer.

The circuit board 203 is provided with circuit traces, electronic components (such as capacitors, resistors, triodes, and MOS transistors), and chips (such as an MCU, a clock data recovery CDR, a power management chip, and a data processing chip DSP).

The circuit board connects the electrical appliances in the optical module together according to the circuit design through circuit wiring to realize the functions of power supply, electrical signal transmission, grounding and the like.

The circuit board is generally a hard circuit board, and the hard circuit board can also realize a bearing effect due to the relatively hard material of the hard circuit board, for example, the hard circuit board can stably bear a chip; when the optical transceiver is positioned on the circuit board, the rigid circuit board can also provide stable bearing; the hard circuit board can also be inserted into an electric connector in the upper computer cage, and specifically, a metal pin/golden finger is formed on the surface of the tail end of one side of the hard circuit board and is used for being connected with the electric connector; these are not easily implemented with flexible circuit boards.

A flexible circuit board is also used in a part of the optical module to supplement a rigid circuit board; the flexible circuit board is generally used in combination with a rigid circuit board, for example, the rigid circuit board may be connected to the optical transceiver device through the flexible circuit board.

The periphery of the silicon optical chip is connected to the circuit board 203 via a plurality of conductive wires, so the silicon optical chip is generally disposed on the surface of the circuit board 203. The silicon optical chip is disposed on the circuit board 203 and electrically connected to the circuit board 203, and may be Wire Bonding, such as via a Gold Wire Bonding. However, the wire diameter of the gold wire is small and fragile, the wiring is dense, and the distance between wires is narrow, so that the phenomena of deformation, damage, collapse and the like are easily caused in the packaging process or the product use process of the optical module, thereby affecting the optical signal quality or causing the defects of short circuit, open circuit and the like. Therefore, a protective cover 300 is arranged, and the protective cover 300 covers the silicon optical chip and is used for protecting the routing of the silicon optical chip.

Specifically, the protective cover 300 covers the circuit board 203, the protective cover 300 covering the circuit board 203 forms a certain space with the circuit board 203, and the silicon optical chip and the routing area of the silicon optical chip are packaged in the space formed by the protective cover 300 and the circuit board 203. It should be noted that the package in the embodiment of the present application refers to an assembly form in which the space formed by the protection cover 300 and the circuit board 203, the silicon optical chip, the wire bonding area of the silicon optical chip, and other optoelectronic devices are in clearance fit with the protection cover 300.

Optionally, the inner surface of the protective cover 300, at a position corresponding to the wiring area, is provided with a first recess for avoiding a gold wire, so that the wiring area of the gold wire can be completely protected, the problems that the gold wire is easily deformed, damaged and collapsed in the existing optical module scheme are effectively solved, and the defects of short circuit, open circuit and the like can be avoided, thereby ensuring the optical signal quality.

The silicon optical chip is connected with an optical fiber socket 400 through an optical fiber ribbon 401, and the optical fiber socket 400 is used for coupling and connecting external optical fibers of the optical module. Optional optical fiber ribbons 401 include a first optical fiber ribbon for transmitting the signal light modulated by the silicon optical chip to the outside of the optical module, and a second optical fiber ribbon for receiving the signal light outside the optical module and transmitting the signal light to the silicon optical chip. The silicon optical chip receives light from the laser assembly, further modulates the light, specifically loads a signal on the light, and transmits the signal to the outside of the optical module through the first optical fiber ribbon; the silicon optical chip receives light from the second optical fiber ribbon and converts the optical signal into an electrical signal.

In order to facilitate the silicon optical chip to receive and emit light, in a specific embodiment of the present application, the silicon optical chip includes a plurality of optical holes, and the plurality of optical holes are configured to receive light transmitted by the laser component, output modulated signal light, and receive signal light transmitted to the silicon optical chip through an optical fiber outside the optical module. Optionally, the silicon optical chip includes a first optical aperture, a second optical aperture, and a third optical aperture, and the optical aperture has a plurality of optical channels therein. The first optical hole is used for coupling and connecting a first optical fiber ribbon and is used for transmitting the modulated signal light to the first optical fiber ribbon; the second optical hole is used for coupling and connecting a second optical fiber ribbon and receiving signal light transmitted through the second optical fiber ribbon; the third light hole is coupled with the laser assembly and used for receiving light which is emitted by the light source and does not carry signals.

The silicon optical chip internally comprises a Mach-Zehnder modulator, and optical signals are modulated by combining the Mach-Zehnder modulator, the transimpedance amplifier, the laser driver and other devices. The Mach-Zehnder modulator modulation adopts the same-wavelength light interference principle, one Mach-Zehnder modulator is provided with two interference arms, one beam of light is input to one single interference arm, two beams of light with the same wavelength need to be provided for one Mach-Zehnder modulator in total, and after the light is modulated by the Mach-Zehnder modulator, the light on the interference arms can be combined into one beam of light.

In an embodiment of the present application, the laser assembly comprises several laser assemblies. The third optical hole comprises a plurality of optical channels, and then a plurality of paths of light with the same wavelength can be input into the silicon optical chip through the optical channels, so as to provide light with the same wavelength for each interference arm of the Mach-Zehnder modulator. Because the light emitting power of a single laser chip is limited, the light of a plurality of laser chips can be superposed to increase the light power of a single wavelength, whereas in the prior art, the light of different wavelengths is generally provided among the plurality of laser chips, and the light power of the single wavelength is not superposed to increase.

Fig. 5 is a schematic front view of the circuit board 203 according to an embodiment of the present disclosure, and fig. 6 is a schematic structural view of the circuit board 203 with a protective cover removed. As shown in fig. 5 and 6, the protective cover 300 is disposed on the circuit board 203, and the laser module, the silicon optical chip 600, and the like are covered in a cavity formed by the protective cover 300 and the circuit board 203.

Fig. 7 is a schematic structural diagram of the circuit board 203 according to an embodiment of the present disclosure, and as shown in fig. 7, the circuit board 203 is provided with a through hole 800, a metal heat sink 700 is embedded in the through hole 800, and a laser upper cover 206, a laser component, and a silicon optical chip 600 are disposed on a surface of the metal heat sink 700; such that the metal heat sink 700 dissipates heat by the thermally conductive material contacting the housing of the optical module.

Fig. 8 is a first schematic structural diagram of a metal heat sink provided in an embodiment of the present application; fig. 9 is a schematic structural diagram of a metal heat sink according to an embodiment of the present application; as shown in fig. 8 and 9, the metal heat sink 700 includes a metal heat sink first region 701, a metal heat sink second region 702, a metal heat sink third region 703, and a metal heat sink fourth region 704. The first metal heat sink area 701, the second metal heat sink area 702 and the third metal heat sink area 703 are arranged side by side, a first gap 705 is arranged between the first metal heat sink area 701 and the second metal heat sink area 702, a second gap 706 is arranged between the second metal heat sink area 702 and the third metal heat sink area 703, and the fourth metal heat sink area 704 is arranged at one end of the first metal heat sink area 701, the second metal heat sink area 702 and the third metal heat sink area 703.

The two ends of the metal heat sink 700 are respectively provided with a first supporting mesa 707 and a second supporting mesa 708, the first supporting mesa 707 and the second supporting mesa 708 are protruding structures of the metal heat sink 700, and when the metal heat sink 700 is embedded inside the through hole 800, the first supporting mesa 707 and the second supporting mesa 708 are used for supporting the circuit board 203, that is, the circuit board 203 is respectively located on the first supporting mesa 707 and the second supporting mesa 708. The distance from the upper surface of the metal heat sink to the upper surface of the first support table top or the second support table top is equal to the thickness of the circuit board.

Meanwhile, in order to achieve the fixed connection between the metal heat sink 700 and the circuit board, glue is generally used to bond the contact between the metal heat sink 700 and the circuit board, so that the first support mesa 707 and the second support mesa 708 facilitate the bonding between the metal heat sink 700 and the circuit board.

Fig. 10 and 11 are respectively an overall and exploded schematic view of the structures arranged on the surface of the metal heat sink, and as shown in fig. 10 and 11, the laser assembly and the silicon optical chip 600 are attached to the metal heat sink 700, and the metal heat sink 700 is fixedly connected to the bottom of the laser upper cover 206 and used for covering the laser assembly, and the laser assembly is arranged between the laser upper cover 206 and the metal heat sink 700. The laser assembly and the silicon optical chip 600 are directly arranged on the metal heat sink, so that the metal heat sink can directly radiate the laser assembly and the silicon optical chip 600, the internal radiation of the optical module can be conveniently realized, and the internal heat of the optical module can be prevented from being concentrated and accumulated. Meanwhile, the laser assembly arranged on the metal heat sink 700 is directly wrapped by the upper cover of the laser, so that the packaging of the laser assembly is saved and the packaging of the laser assembly is facilitated. Further, the laser component and the silicon optical chip 600 are directly attached to the metal heat sink 700, so that the laser component and the silicon optical chip 600 are located on the same metal heat sink, that is, the laser component and the silicon optical chip 600 share the metal heat sink; when the metal heat sink 700 is heated to generate deformation, the influence on the laser component and the silicon optical chip 600 is the same, so that the optical alignment stability of the laser component and the silicon optical chip 600 is good, and the assembly requirement of the laser component and the silicon optical chip is further simplified.

Optionally, the metal heat sink 700 is fixedly connected to the bottom of the laser upper cover 206, for example, a fixing glue is used to fix the bottom of the laser upper cover 206 on the metal heat sink 700. The laser top cover 206 cooperates with the circuit board and the metal heat sink 700 to provide a relatively sealed environment for the laser assembly, thereby protecting the components of the laser assembly. The upper surface of the silicon optical chip 600 is provided with a transimpedance amplifier 601 and a laser driver 602.

The laser assembly comprises a first laser assembly 501 and a second laser assembly 502, and the first laser assembly 501 and the second laser assembly 502 emit light which does not carry signals. The first laser assembly 501 and the second laser assembly 502 are attached to a metal heat sink 700. Optionally, the first laser assembly 501 and the second laser assembly 502 are connected to a circuit on the circuit board by wire bonding.

Further, the optical module provided by the embodiment of the application further comprises a lens and an isolator. The lens, isolator and laser assembly cooperate to form a cavity between the laser top cover 206 and the metal heat sink 700. For example, a lens, specifically a focusing lens, is disposed in the light-emitting direction of the laser chip, and is located between the laser chip and the sealed light-transmitting member, and is used for converging light emitted by the laser chip for subsequent coupling; or two lenses, specifically a collimating lens and a focusing lens, are arranged in the light emitting direction of the laser chip, light emitted by the laser chip is changed into collimated light through the collimating lens, the collimated light can keep smaller optical power attenuation in the longer distance light transmission process, and the focusing lens receives the collimated light so as to converge and couple the light into the silicon optical chip. The isolator is used for preventing light emitted by the laser chip from returning to the laser chip after being emitted, so that the isolator is arranged in the light emitting direction of the laser chip. In the embodiment of the application, the isolator is arranged in the direction of the lens towards the laser chip, namely, a focusing lens is arranged between the isolator and the laser chip.

A first collimating lens, a first focusing isolator and a focusing lens are sequentially arranged along the light-emitting direction of the first laser assembly 501, and a second collimating lens, an isolator and a second focusing lens are sequentially arranged along the light-emitting direction of the second laser assembly 502. The first laser assembly 501 and the second laser assembly 502 may share an isolator and a sealed optically transparent member. The first collimating lens, the first focusing lens, the second collimating lens, the second focusing lens, the isolator and the sealing light-transmitting member are fixedly disposed on the metal heat sink 700.

Fig. 12 is a schematic diagram of a metal heat sink embedded in a circuit board in a top view according to an embodiment of the present application; fig. 13 is a schematic diagram of a metal heat sink embedded in a circuit board according to an embodiment of the present disclosure from a side view; fig. 14 is a schematic diagram illustrating a metal heat sink according to an embodiment of the present application exploded from a circuit board; fig. 15 is a schematic cross-sectional view of a metal heat sink embedded in a circuit board according to an embodiment of the present disclosure; as shown in fig. 12 to 15, in the present application, the metal heat sink 700 is embedded in the through hole 800, specifically, the end surfaces of the two ends of the circuit board 203, which are dug in the through hole 800, are respectively located on the surfaces of the first supporting mesa 707 and the second supporting mesa 708 of the metal heat sink 700, and after the embedding, the structures on the surface of the metal heat sink can be seen from a top view angle, and as seen from a side view angle, the two protruding supporting mesas of the metal heat sink play a role of supporting the circuit board 203.

In order to realize the grounding of the silicon optical chip, the grounding of the metal heat sink is realized, so that the grounding of the silicon optical chip is realized.

As mentioned above, the metal heat sink 700 of the present application is provided with a first supporting mesa 707 and a second supporting mesa 708 at two ends, respectively, the lower surface of the circuit board 203 is provided with a first metal layer 801 at a contact area with the upper surface of the first supporting mesa 707, the lower surface of the circuit board 203 is provided with a second metal layer 802 at a contact area with the upper surface of the second supporting mesa 708, the first support mesa 707 is electrically connected to the first metal layer 801, the second support mesa 708 is electrically connected to the second metal layer 802, the first metal layer 801 and the second metal layer 802 are electrically connected to a ground layer of the circuit board 203, respectively, to achieve grounding of the metal heat sink 700, specifically, the ground layer of the circuit board 203 is disposed on an inner layer of the circuit board, the first metal layer 801 is connected with the ground layer of the circuit board through a via hole, and the second metal layer 802 is connected with the ground layer of the circuit board through a via hole.

Fig. 16 is a schematic top view of a metal heat sink provided in an embodiment of the present application; fig. 17 is a schematic structural diagram of a metal layer laid on the periphery of a through hole according to an embodiment of the present application; fig. 18 is a schematic diagram of a relative position relationship between a metal heat sink setting support surface and a metal layer laid on the periphery of a through hole according to an embodiment of the present application. As shown in fig. 16 to 18, the shape of the first metal layer 801 is consistent with the shape of the contact area between the upper surface of the first supporting platform and the lower surface of the circuit board, that is, the shapes of the first metal layer 801 and the first supporting platform 707 are consistent; the shape of the second metal layer 802 is consistent with the shape of the contact area between the upper surface of the second support mesa and the lower surface of the circuit board, i.e., the shape of the second metal layer 802 is consistent with the shape of the second support mesa 708. Specifically, the first support mesa 707 is disposed around one end of the metal heat sink 700, and the second support mesa 708 is disposed around the other end of the metal heat sink 700; the first metal layer 801 is disposed around the periphery of one end of the through hole 800, and the second metal layer 802 is disposed around the periphery of the other end of the through hole 800. Further, the first support mesa 707 is disposed around one end of the metal heat sink 700 and portions of two sides adjacent to the one end, the second support mesa 708 is disposed around the other end of the metal heat sink 700 and portions of two sides adjacent to the one end, the first metal layer 801 is disposed around one end of the periphery of the through hole 800 and portions of two sides adjacent to the one end, and the second metal layer 802 is disposed around the other end of the periphery of the through hole 800 and portions of two sides adjacent to the one end.

The first supporting mesa 707 is connected to the first metal layer 801 by a conductive silver paste, and the second supporting mesa 708 is connected to the second metal layer 802 by a conductive silver paste.

Thus, the two ends of the metal heat sink are respectively provided with a first supporting table surface and a second supporting table surface, the first supporting table surface and the second supporting table surface are used for supporting the circuit board, the lower surface of the circuit board is provided with a first metal layer at the contact area with the upper surface of the first supporting table surface, the lower surface of the circuit board is provided with a second metal layer at the contact area with the upper surface of the second supporting table surface, the first supporting table surface is electrically connected with the first metal layer, the second supporting table surface is electrically connected with the second metal layer, the first metal layer and the second metal layer are both electrically connected with the grounding layer of the circuit board, because the first supporting table surface and the second supporting table surface are both electrically connected with the corresponding metal layers, the grounding connection of the metal heat sink can be realized, because the silicon optical chip is attached on the metal heat sink, the grounding connection of the silicon optical chip can be realized, so as to ensure the normal work of the silicon optical chip, and avoid the parasitic inductance caused by the grounding connection of the silicon optical chip through gold wires in the prior art, the quality of signal transmission is guaranteed.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention in its corresponding aspects.

Claims

1. A light module, comprising:

a circuit board having a through hole;

2. The optical module of claim 1, wherein the ground plane of the circuit board is disposed on an inner layer of the circuit board, the first metal layer is connected to the ground plane of the circuit board through a via, and the second metal layer is connected to the ground plane of the circuit board through a via.

3. The optical module of claim 1, wherein the first metal layer has a shape that conforms to a shape of the first support mesa;

the shape of the second metal layer is consistent with the shape of the second support table-board.

4. The optical module of claim 1, wherein the first and second support mesas are protruding structures relative to the metal heat sink.

5. The optical module of claim 1, wherein the first support mesa is disposed around one end of the metal heat sink and the second support mesa is disposed around the other end of the metal heat sink.

6. The optical module of claim 1, wherein the first metal layer is disposed around a periphery of one end of the through hole, and the second metal layer is disposed around a periphery of the other end of the through hole.

7. The optical module of claim 1, wherein a distance from an upper surface of the metal heat sink to an upper surface of the first support mesa or the second support mesa is equal to a thickness of the circuit board.

8. The optical module of claim 1, wherein the first support mesa is connected to the first metal layer by a conductive silver paste, and the second support mesa is connected to the second metal layer by a conductive silver paste.

9. The optical module of claim 1, wherein the metal heat sink and the through hole are coated with glue therebetween.