CN111555811B

CN111555811B - Optical module

Info

Publication number: CN111555811B
Application number: CN202010322966.2A
Authority: CN
Inventors: 张加傲; 王欣南
Original assignee: Hisense Broadband Multimedia Technology Co Ltd
Current assignee: Hisense Broadband Multimedia Technology Co Ltd
Priority date: 2020-04-22
Filing date: 2020-04-22
Publication date: 2023-07-14
Anticipated expiration: 2040-04-22
Also published as: CN111555811A

Abstract

The application discloses an optical module, which comprises a circuit board; the light emitting assembly is electrically connected with the circuit board and is used for emitting light signals; an optical receiving assembly for receiving an optical signal from outside the optical module; a flexible board for connecting the light receiving assembly and the circuit board; wherein the light receiving assembly comprises: a housing; a light receiving device disposed in the housing for receiving an optical signal of an external optical fiber; and the transimpedance amplifier is arranged on the surface of the flexible board inserted into the shell, is connected with the light receiving device and is electrically connected with the circuit board through the flexible board, and is used for transmitting the amplified electric signal to the circuit board. The optical module that this application provided is with optical receiving assembly integration on the flexible sheet, and rethread flexible sheet is connected optical receiving assembly to the circuit board on, has avoided transmitting end and receiving end's chip all to integrate on the circuit board, has separated the distance of receiving and dispatching the chip in the follow space through external flexible sheet, application space isolation, means such as position isolation have fundamentally solved the problem of circuit crosstalk.

Description

Optical module

Technical Field

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

Background

The optical module is mainly used for photoelectric and electro-optical conversion, the transmitting end of the optical module converts an electric signal into an optical signal and transmits the optical signal out through an optical fiber, and the receiving end of the optical module converts the received optical signal into an electric signal. The current packaging forms of optical modules mainly include TO (transmitter-output) packaging and COB (Chip on Board) packaging.

In the high-speed optical modules adopted by the existing data center, a micro-optical COB packaging scheme is adopted, the optical modules adopting the COB scheme are adopted under the normal condition, the chips of the transmitting end and the receiving end are integrated on the PCB, the transmitting and receiving chips are mostly integrated on one surface of the PCB, and particularly, 8 channels are arranged for transmitting and receiving the high-speed 200G optical modules, and the distances between the transmitting channels and the receiving channels on the PCB are very close. In this case, since the power of the transmitting end is much larger than that of the receiving end and the circuit wirings are adjacent to each other, a case of circuit crosstalk is very easy to occur. When solving such a circuit crosstalk problem, a common mode in industry is to use a ground wire as a space for shielding, that is, use the ground wire to separate a transmitting chip and a receiving chip on a PCB board, so as to shield the circuit crosstalk between the transmitting end and the receiving end.

However, when the above-mentioned manner is adopted, because the space layout is compact, that is, the ground wire is used to separate the transceiver chip on the PCB board, the channel wiring distance between the transmitter chip and the receiver chip is still relatively short, and the circuit crosstalk between the transceiver terminals cannot be completely solved.

Disclosure of Invention

The application provides an optical module to solve the problem that the circuit crosstalk is caused because of the passageway wiring distance is nearer between the transceiver chip on the PCB board of present optical module.

In order to solve the technical problems, the embodiment of the application discloses the following technical scheme:

in a first aspect, an embodiment of the present application discloses an optical module, including:

a circuit board;

the light emitting assembly is electrically connected with the circuit board and is used for emitting light signals;

an optical receiving assembly for receiving an optical signal from outside the optical module;

a flexible board for connecting the light receiving assembly and the circuit board;

wherein the light receiving assembly comprises:

a housing;

a light receiving device disposed in the housing for receiving an optical signal of an external optical fiber;

and the transimpedance amplifier is arranged on the surface of the flexible board inserted into the shell, is electrically connected with the light receiving device and is electrically connected with the circuit board through the flexible board and is used for transmitting the amplified electric signal to the circuit board.

In a second aspect, an embodiment of the present application further discloses an optical module, including:

a circuit board;

wherein the light receiving assembly comprises:

a housing;

a base plate disposed in the housing for supporting a flexible board inserted into the housing;

and the transimpedance amplifier is arranged on the surface of the base plate through a mounting hole arranged on the flexible plate, is electrically connected with the light receiving device, is electrically connected with the circuit board through the flexible plate and is used for transmitting the amplified electric signal to the circuit board.

In the optical module provided by the application, the optical emission component is electrically connected with the circuit board, the optical receiving component is integrated on the flexible board, the optical receiving component is connected to the circuit board through the flexible board, the integration of the optical emission component and the optical receiving component on the PCB is avoided, a large amount of space is saved for the PCB, the distance of the transceiver chip is separated from the space through the external flexible board under the condition of not increasing the space requirement of the PCB, and the problems of circuit crosstalk are fundamentally solved by means of space isolation, position isolation and the like; in addition, the transimpedance amplifier is arranged on the surface of the flexible board inserted into the shell, is connected with the light receiving device arranged in the shell and is electrically connected with the circuit board through the flexible board, so that the receiving channel and the transmitting channel on the circuit board are separated, the shell can isolate the electric signal of the transimpedance amplifier, the electric signal of the transimpedance amplifier is prevented from being influenced by the electric signal of the light transmitting component, and the problem of crosstalk between the circuit of the receiving channel and the circuit of the transmitting channel can be fundamentally solved.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application.

Drawings

In order to more clearly illustrate the technical solutions of the present application, the drawings that are needed in the embodiments will be briefly described below, and it will be obvious to those skilled in the art that other drawings can be obtained from these drawings without inventive effort.

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

fig. 2 is a schematic diagram of an optical network terminal structure;

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

fig. 4 is an exploded schematic view of an optical module according to an embodiment of the present application;

FIG. 5 is a block diagram of a circuit board in an embodiment of the present application;

fig. 6 is an exploded view of a circuit board according to an embodiment of the present application;

FIG. 7 is a block diagram of a receiving assembly in an embodiment of the present application;

FIG. 8 is an exploded view of a receiver assembly according to an embodiment of the present application;

FIG. 9 is a schematic partial structure of a receiving assembly according to an embodiment of the present application;

FIG. 10 is an enlarged schematic view of a portion of FIG. 9A;

FIG. 11 is a partial cross-sectional view of a receiving assembly in an embodiment of the present application;

fig. 12 is a partially enlarged schematic view of fig. 11 at B.

Detailed Description

In order to better understand the technical solutions in the present application, the following description will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only some embodiments of the present application, but not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments herein without making any inventive effort, shall fall within the scope of the present application.

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

The optical module realizes the function of the mutual conversion of the optical signal and the electric signal in the technical field of optical fiber communication, and the mutual conversion of the optical signal and the electric signal 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 main electrical connection comprises power supply, I2C signals, data information, grounding and the like; the electrical connection mode realized by the golden finger has become the mainstream connection mode of the optical module industry, and on the basis of the main connection mode, the definition of pins on the golden finger forms various industry protocols/specifications.

Fig. 1 is a schematic diagram of a 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 remote 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 remote 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.

The optical port of the optical module 200 is externally connected to the optical fiber 101, and bidirectional optical signal connection is established with the optical fiber 101; the electrical port of the optical module 200 is externally connected into the optical network terminal 100, and bidirectional electrical signal connection is established with the optical network terminal 100; the optical module is internally provided with an optical module, and the optical module is internally provided with an optical signal and an electric signal, so that information connection between the optical fiber and the optical network terminal is established. 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 the 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; a connection is established between the optical module 200 and 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, transmits the signal from the network cable to the optical module, and monitors the operation of the optical module as an upper computer of the optical module.

So far, the remote server establishes a bidirectional signal transmission channel with the local information processing equipment 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, which provides data signals for the optical module and receives data signals from the optical module, and the common optical module upper computer also includes 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 includes a circuit board 105, and a cage 106 is provided on a surface of the circuit board 105; an electrical connector is arranged in the cage 106 and is used for accessing an optical module electrical port such as a golden finger; the cage 106 is provided with a radiator 107, and the radiator 107 has a convex portion such as a fin that increases a heat radiation area.

The optical module 200 is inserted into the optical network terminal 100, specifically, an electrical connector inside the cage 106 is inserted into an electrical port of the optical module, 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 inside the cage; the light module is inserted into the cage, the light module is fixed by the cage, and the heat generated by the light module is conducted to the cage 106 and then diffused through the heat sink 107 on the cage.

Fig. 3 is a schematic structural diagram of an optical module provided in an embodiment of the present application, and fig. 4 is an exploded structural diagram of an optical module provided in an embodiment of the present application. As shown in fig. 3 and 4, the optical module 200 provided in the embodiment of the present application includes an upper housing 201, a lower housing 202, an unlocking member 203, a circuit board 300, and an optical transceiver assembly 400.

The upper case 201 is covered on the lower case 202 to form a packing cavity having two openings; the outer contour of the wrapping cavity generally presents a square shape. Specifically, the lower housing 202 includes a main board and two side boards located at two sides of the main board and arranged perpendicular to the main board; the upper shell comprises a cover plate, and the cover plate covers the two side plates of the upper shell to form a wrapping cavity; the upper case may further include two sidewalls disposed at both sides of the cover plate and perpendicular to the cover plate, and the two sidewalls are combined with the two side plates to realize the covering of the upper case 201 on the lower case 202.

The two openings can be two ends openings (204, 205) in the same direction or two openings in different directions; one opening is an electric port 204, and a golden 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, which is used for external optical fiber access to connect with the optical transceiver assembly 400 inside the optical module; the circuit board 300, the optical transceiver assembly 400, and other optoelectronic devices are located in the encapsulation cavity.

The upper shell and the lower shell are combined to be assembled, so that devices such as the circuit board 300, the optical transceiver assembly 400 and the like can be conveniently installed in the shells, and the upper shell and the lower shell form an encapsulation protection shell of the outermost layer of the module; the upper shell and the lower shell are made of metal materials, electromagnetic shielding and heat dissipation are realized, the shell of the optical module is not made into an integral part, and therefore, when devices such as a circuit board and the like are assembled, the positioning part, the heat dissipation and the electromagnetic shielding part cannot be installed, and the production automation is not facilitated.

The unlocking component 203 is located on the outer wall of the lower housing 202, and is used for realizing or releasing the fixed connection between the optical module and the host computer.

The unlocking part 203 is provided with a clamping part matched with the upper computer cage; pulling the end of the unlocking member can relatively move the unlocking member 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; the unlocking part is pulled, and the clamping part of the unlocking part moves along with the unlocking part, so that the connection relation between the clamping part and the upper computer is changed, the clamping relation between the optical module and the upper computer is relieved, and the optical module can be pulled out of the cage of the upper computer.

The circuit board 300 is provided with circuit wiring, electronic components (such as capacitor, resistor, triode, MOS tube) and chips (such as MCU, laser driving chip, limiting amplifying chip, clock data recovery CDR, power management chip, data processing chip DSP), etc.

The circuit board 300 connects the electrical devices in the optical module together according to a circuit design through circuit wiring, so as to realize electrical functions such as 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 bearing effect due to the relatively hard material of the hard circuit board, for example, the hard circuit board can stably bear chips; when the optical transceiver component is positioned on the circuit board, the hard circuit board can provide stable bearing; the hard circuit board can also be inserted into an electric connector in the upper computer cage, specifically, a metal pin/golden finger is formed on the end surface of one side of the hard circuit board and is used for being connected with the electric connector; these are all inconvenient to implement with flexible circuit boards.

A flexible circuit board is also used in part of the optical modules and is used as a supplement of the hard circuit board; the flexible circuit board is generally used in cooperation with the hard circuit board, for example, the hard circuit board and the optical transceiver assembly can be connected by using the flexible circuit board.

The optical transceiver component comprises an optical transmitting component and an optical receiving component, which are respectively used for realizing the transmission of optical signals and the reception of the optical signals. Fig. 5 is a schematic structural diagram of a circuit board 300 according to an embodiment of the present application, and fig. 6 is an exploded structural diagram of the circuit board 300 according to an embodiment of the present application. As shown in fig. 5 and 6, a light emitting assembly 401 and a flexible board 500 are disposed on the circuit board 300, and the light emitting assembly 401 includes a light emitter and a laser driving chip, which are electrically connected to the circuit board 300, for emitting light signals; one end of the flexible board 500 is fixed on the circuit board 300, and the other end extends into the light receiving component 402, namely, the light receiving component 402 is connected with the circuit board 300 through the flexible board 500, so that the light receiving component 402 does not need to be integrated on the circuit board 300, and the light emitting component 401 and the light receiving component 402 are prevented from being integrated on the circuit board, and the synchronous wiring distance between the light emitting component and the light receiving component is relatively short. That is, the flexible board 500 is a carrier for mounting components such as the light receiving module 402, and is generally made of a flexible material.

The light emitting assembly 401 generally includes a housing, a light emitter and a lens assembly, the light emitter being fixed inside the housing for emitting a light beam; the lens component is positioned on the luminous light path of the light emitter and fixed in the shell, and is used for changing the transmission direction of the light beam so that the laser beam enters the external optical fiber. That is, light from the light emitter is reflected by the lens assembly and enters the optical fiber.

Fig. 7 is a schematic structural diagram of a light receiving assembly 402 according to an embodiment of the present application, and fig. 8 is a schematic exploded structural diagram of the light receiving assembly 402 according to an embodiment of the present application. As shown in fig. 7 and 8, the light receiving assembly 402 includes a housing 4021, a lens assembly (not shown), a light receiving device 4022, and a transimpedance amplifier 501, the light receiving device 4022 being fixed inside the housing 4021 for receiving an optical signal of an external optical fiber; the lens component is disposed between the light receiving device 4022 and the external optical fiber 101, and is used for reflecting the light from the external optical fiber 101 through the lens component and then entering the light receiving device 4022; one end of the flexible board 500 is inserted into the housing 4021, and a transimpedance amplifier 501 is provided on the surface of the flexible board 500 inserted into the housing 4021, and is connected to the light receiving device 4022 for amplifying an electric signal output from the light receiving device 4022, that is, converting a weak signal current output from the light receiving device 4022 into a signal voltage output with a sufficient amplitude by the transimpedance amplifier 501, so that the amplitude of the voltage signal output from the transimpedance amplifier 501 satisfies the requirement of the subsequent system board for the signal amplitude. The transimpedance amplifier 501 is electrically connected to the circuit board 300 through the flexible board 500 to transmit the amplified electrical signal to the circuit board 300, and the circuit board 300 performs subsequent processing on the electrical signal.

Since the flexible board 500 is made of a flexible material, the flexibility is strong, and in order to insert the flexible board 500 into the housing 4021, a substrate 600 is provided in the housing 4021, and the substrate 600 is located between the flexible board 500 inserted into the housing 4021 and the bottom plate of the housing 4021, for supporting the flexible board 500.

In this example, the light receiving device 4022 is often a PIN photodiode and an avalanche photodiode APD that converts an optical signal in the external optical fiber 101 into an electrical signal using a photoelectric effect.

The flexible board 500 integrated with the transimpedance amplifier 501 is inserted into the housing 4021 and connected with the light receiving device 4022 in the housing 4021, and then the flexible board 500 is fixedly mounted on the circuit board 300, so that the light emitting component 401 and the light receiving component 402 are spatially separated by externally connecting the flexible board, and the light emitting channel and the light receiving channel are prevented from being close in wiring distance.

When the flexible board 500 is fixedly mounted on the circuit board 300, the flexible board 500 and the light emitting component 401 can be respectively mounted on different sides of the circuit board 300, so that the receiving channel and the emitting channel on the circuit board 300 are not on the same surface, and the crosstalk problem of the light receiving channel and the light emitting channel is avoided. The flexible board 500 and the light emitting component 401 may also be mounted on the same side of the circuit board 300, that is, the receiving channel and the emitting channel on the circuit board 300 are on the same surface, and the transimpedance amplifier 501 and the light receiving device 4022 are disposed inside the housing 4021, so that the crosstalk problem between the light receiving channel and the light emitting channel can be reduced due to the isolation effect of the housing 4021.

The housing 4021 includes a package shell 4024 and a cover plate 4023 pressed on the package shell 4024, the package shell 4024 and the cover plate 4023 form a receiving cavity, the light receiving component 402 is placed in the receiving cavity, and the flexible board 500 integrated with the transimpedance amplifier 501 is inserted into the receiving cavity, so as to realize micro-optical COB package of the light receiving component 402.

Fig. 9 is a schematic partial structure of a light receiving component 402 according to an embodiment of the present application. As shown in fig. 8 and 9, the package shell 4024 is composed of a bottom plate and four side plates adjacent to the bottom plate, wherein a first slot 4028 is formed in one side plate, and the first slot 4028 corresponds to the flexible board 500, that is, the flexible board 500 is inserted into the package shell 4024 through the first slot 4028.

In order to limit the flexible board 500 when the flexible board 500 is inserted into the packaging shell 4024, a mounting groove 4025 is formed in a bottom plate of the packaging shell 4024, the mounting groove 4025 corresponds to the first groove 4028, namely, the bottom surface of the mounting groove 4025 is parallel to the bottom surface of the first groove 4028, and when the end surface of the flexible board 500 is inserted into the first groove 4028, the flexible board 500 is aligned with the first groove 4028, so that the bottom surface of the flexible board 500 contacts with the bottom surface of the first groove 4028; the flexible board 500 is then pushed so that the bottom surface of the flexible board 500 moves on the bottom surface of the mounting groove 4025 until the end surface of the flexible board 500 abuts against the side wall of the mounting groove 4025.

In this example, the width dimension of the first slot 4028 may be equal to the width dimension of the flexible board 500 such that the flexible board 500 is inserted into the first slot 4028; the width dimension of the first slot 4028 may also be slightly greater than the width dimension of the flexible board 500, leaving a portion of the space for facilitating insertion of the flexible board 500 into the first slot 4028. Similarly, the thickness dimension of the first slot 4028 may be equal to the sum of the thickness dimension of the flexible board 500 and the thickness dimension of the transimpedance amplifier 501, such that the flexible board 500 is inserted into the first slot 4028; the thickness dimension of the first slot 4028 may also be greater than the thickness dimension of the flexible board 500, leaving a portion of the space for facilitating insertion of the flexible board 500 into the first slot 4028.

The size of the mounting groove 4025 on the bottom plate of the package shell 4024 in the mounting direction of the flexible board 500 can be determined according to the position of the light receiving device 4022 in the package shell 4024 and the size of the package shell 4024, so that after the flexible board 500 extends into the package shell 4024 through the first groove 4028 and is fixed in the mounting groove 4025, the light receiving device 4022 and the transimpedance amplifier 501 on the flexible board 500 can be conveniently connected.

Fig. 10 is a partially enlarged schematic illustration of a light receiving component 402 according to an embodiment of the present application. As shown in fig. 10, an observation hole 4029 is provided on the other side plate of the package shell 4024, the side plate where the observation hole 4029 is located is adjacent to the side plate where the first slot 4028 is located, and the observation hole 4029 corresponds to the side wall of the mounting slot 4025 on the bottom plate of the package shell 4024. The light receiving device 4022 includes a detector and an AWG (Arrayed Waveguide Grating ), the photosensitive surface of the detector faces the output waveguide end of the AWG, and the distance between the photosensitive surface of the detector tube and the output waveguide end of the AWG enables the two to be directly coupled, so that the coupling between the AWG and the detector can be observed through the observation hole 4029, and the front and rear positions of the AWG can be conveniently adjusted.

When the flexible board 500 is inserted into the package case 4024 through the first slot 4028, the substrate 600 may be adhered to the bottom surface of the mounting slot of the package case 4024, and then the flexible board 500 is adhered to the substrate 600, so as to fix the flexible board 500 in the package case 4024.

A second slot 4026 is provided on the other side plate of the package shell 4024 opposite to the side plate where the first slot 4028 is located, and the second slot 4026 corresponds to the light receiving device 4022, that is, the light receiving device 4022 is inserted into the package shell 4024 through the second slot 4026.

After the light receiving device 4022 is inserted into the package case 4024 through the second slot 4026, the light receiving device 4022 is pushed until the end surface of the light receiving device 4022 is close to the side wall of the mounting slot 4025, and then the light receiving device 4022 may be adhered to the bottom plate of the package case 4024 to fix the light receiving device 4022 in the package case 4024.

The mounting process of the light receiving assembly 402 is: firstly, the light receiving device 4022 is inserted into the packaging shell 4024 through the second slot 4026 until the end face of the light receiving device 4022 is close to the side wall of the mounting slot 4025, and then the light receiving device 4022 is fixed on the bottom plate of the packaging shell 4024; the transimpedance amplifier 501 is then fixed on the surface of the flexible board 500; then the flexible board 500 integrated with the transimpedance amplifier 501 is inserted into the packaging shell 4024 through the first slot 4028 until the end surface of the flexible board 500 abuts against the side wall of the mounting slot 4025; after the flexible board 500 and the light receiving device 4022 are fixed, the cover plate 4023 is pressed against the opening of the packaging case 4024, and the transimpedance amplifier 501 and the light receiving device 4022 are packaged in the case 4021.

A transimpedance amplifier 501 may be disposed on the surface of the flexible board 500 inserted into the housing 4021, that is, the optical module has a set of light receiving components 402 and a set of light emitting components 401, so that a second slot 4026 is disposed on a side board opposite to the side board where the first slot 4028 is disposed, and the light receiving components are electrically connected to the circuit board 300 by externally connecting the flexible board. A plurality of transimpedance amplifiers 501 may be further disposed on the surface of the flexible board 500 inserted into the housing 4021, that is, the optical module has a plurality of groups of optical receiving assemblies 402 and a plurality of groups of optical transmitting assemblies 401, the plurality of groups of optical receiving assemblies 402 are packaged in the same receiving cavity, the plurality of groups of optical transmitting assemblies 401 are respectively packaged, and the packaged plurality of groups of optical transmitting assemblies 401 are respectively electrically connected with the circuit board 300.

When the plurality of transimpedance amplifiers 501 are provided on the surface of the flexible board 500 inserted into the housing 4021, a plurality of second grooves (4026, 4027) are provided side by side on the side plate opposite to the side plate on which the first groove 4028 is provided, and a plurality of light receiving devices 4022 are inserted into the housing 4021 through the plurality of second grooves (4026, 4027) to accommodate the high-speed optical module.

After the transimpedance amplifier 501 is integrated on the flexible board 500, a wiring layer (not shown in the figure) is disposed on a side of the flexible board 500 facing the circuit board 300, and the transimpedance amplifier 501 is connected to the circuit board 300 through the wiring layer. The trace layer has 8 differential channels, and the 8 differential channels are connected with the circuit board 300 to realize subsequent processing of the electrical signals.

A power supply wiring layer (not shown in the figure) is arranged below the wiring layer, and the power supply wiring layer is arranged on one side of the transimpedance amplifier 501 and is used for supplying power to the transimpedance amplifier 501. The signal wiring and the power line electric crosstalk problem on the flexible board 500 are solved, the signal wiring and the power line are distributed in a crossing manner in the wiring design process, namely, the signal wiring is arranged on the upper layer of the flexible board, the power wiring is arranged below the signal wiring, the position isolation of the signal wiring and the power line is realized, and the influence of the circuit crosstalk is reduced to the greatest extent.

When the transimpedance amplifier 501 is placed on the flexible board 500, the transimpedance amplifier 501 may be directly attached to the surface of the flexible board 500 inserted into the housing 4021, or a hole may be bored in the flexible board 500, the transimpedance amplifier 501 may be fitted into the hole, and the transimpedance amplifier may be mounted on the surface of the substrate 600 through the hole.

Fig. 11 is a schematic cross-sectional view of a light receiving module 402 according to an embodiment of the present disclosure; fig. 12 is an enlarged schematic view at B of fig. 11. As shown in fig. 11 and 12, since the flexible board 500 is made of a soft material, the flexible board 500 is easily deformed, and therefore, the substrate 600 is disposed between the flexible board 500 and the mounting groove 4025 on the bottom plate of the package case 4024, and the substrate 600 can prevent the flexible board 500 from being deformed and support the flexible board 500.

In this example, the substrate 600 is located below the flexible board 500, and can be inserted into the mounting groove 4025 through the first slot 4028 to support one end of the flexible board 500 integrated with the transimpedance amplifier 501, and an end surface of the substrate 600 abuts against a sidewall of the mounting groove 4025. Specifically, the substrate 600 may be adhered to the bottom surface of the flexible board 500 opposite to the transimpedance amplifier 501, and then the flexible board 500 is inserted into the mounting groove 4025 together with the substrate 600 through the first groove 4028 until the end surface of the flexible board 500, the end surface of the substrate 600 and the side wall of the mounting groove 4025 abut.

In this example, a mounting hole (not shown in the drawing) through which the transimpedance amplifier 501 is mounted on the surface of the substrate 600 may be provided on the flexible board 500 inserted into the housing 4021, and the transimpedance amplifier 501 mounted on the substrate 600 is electrically connected to the light receiving device 4022 and to the circuit board 300 through the flexible board 500 for transmitting the amplified electric signal to the circuit board 300.

For the high-speed 200G optical module, there are generally a plurality of sets of light receiving elements and light emitting elements, that is, a plurality of transimpedance amplifiers 501 are integrated on the flexible board 500, and thus, a plurality of mounting holes (not shown) may be provided on the flexible board 500 inserted into the housing 4021, and the plurality of transimpedance amplifiers 501 are mounted on the surface of the substrate 600 through the plurality of mounting holes.

In this example, the optical module has two sets of light receiving assemblies 402, such that a second slot 4026 and a fourth slot 4027 are disposed on the other side plate of the package shell 4024 opposite to the side plate where the first slot 4028 is located, the second slot 4026 and the fourth slot 4027 are disposed in parallel, and the second slot 4026 and the fourth slot 4027 correspond to the two light receiving devices 4022, that is, one light receiving device 4022 is inserted into the package shell 4024 through the second slot 4026, and the other light receiving device 4022 is inserted into the package shell 4024 through the fourth slot 4027.

After the two light receiving devices 4022 are inserted into the package case 4024 through the second slot 4026 and the fourth slot 4027, the two light receiving devices 4022 are pushed until the end surfaces of the two light receiving devices 4022 are close to the side wall of the mounting slot 4025, and then the two light receiving devices 4022 can be respectively adhered to the bottom plate of the package case 4024, so that the two light receiving devices 4022 are fixed in the package case 4024.

The mounting process of the two light receiving modules 402 is: firstly, two light receiving devices 4022 are respectively inserted into a packaging shell 4024 through a second notch 4026 and a fourth notch 4027 until the end surfaces of the two light receiving devices 4022 are close to the side wall of a mounting groove 4025, and then the two light receiving devices 4022 are fixed on the bottom plate of the packaging shell 4024; two transimpedance amplifiers 501 are then mounted on the substrate 600 by means of mounts Kong Binglie on the flex board 500; then, the flexible board 500 integrated with the two transimpedance amplifiers 501 and the substrate 600 are inserted into the packaging shell 4024 through the first slot 4028 until the end surfaces of the flexible board 500 and the substrate 600 are abutted against the side walls of the mounting slot 4025; after the flexible board 500 and the light receiving devices 4022 are fixed, the cover plate 4023 is pressed at the opening of the packaging shell 4024, and the two transimpedance amplifiers 501 and the two light receiving devices 4022 are packaged in the shell 4021.

After integrating the two transimpedance amplifiers 501 on the flexible board 500, a wiring layer (not shown in the figure) is provided on the side of the flexible board 500 facing the circuit board 300, and the two transimpedance amplifiers 501 are connected to the circuit board 300 through the wiring layer. The trace layer has 8 pairs of differential channels, and the 8 pairs of differential channels are connected with the circuit board 300 to realize subsequent processing of the electrical signals.

The wiring layer is disposed on the flexible board 500, so that the light receiving component 402 is integrated on the flexible board 500, and the transimpedance amplifier 501 is integrated on the independent flexible board 500, so that the light receiving channel and the light emitting channel are spatially separated.

The number of the transimpedance amplifiers 501 integrated on the flexible board 500 is not limited to one or two of the above embodiments, and a plurality of transimpedance amplifiers can be integrated according to actual requirements, so that the optical module has a plurality of receiving channels, which all belong to the protection scope of the embodiments of the present application.

When the flexible board 500 is welded to the bottom surface of the circuit board 300, the electrical chips of the light emitting assembly 401 are integrated on the top surface of the circuit board 300, that is, the flexible board 500 and the light emitting assembly 401 are respectively located at different sides of the circuit board 300, so that separation of the emitting link and the receiving link in space is realized, the channel wiring distance between the emitting electrical chip and the receiving electrical chip is avoided, and the problem of circuit crosstalk is fundamentally solved by means of space isolation, position isolation and the like.

When the flexible board 500 is welded to the top surface of the circuit board 300, the electrical chips of the light emitting assembly 401 are also integrated on the top surface of the circuit board 300, that is, the flexible board 500 and the light emitting assembly 401 are located on the same side of the circuit board 300, because the light receiving device 4022 and the transimpedance amplifier 501 are packaged in the housing 4021, the distance between the transmitting and receiving chips is separated from space through the external flexible board on the premise of not increasing the space requirement of the circuit board, and the problem of circuit crosstalk between the transmitting electrical chips and the receiving electrical chips is avoided by the isolation function of the housing 4021 and by means of space isolation, position isolation and the like.

The wiring structure that the flexible board and the receiving chip transimpedance amplifier are integrated together is adopted, although the integrated electric chip can be adopted on the flexible board in the coaxial packaging mode, the purpose is only passive selection under the condition that wiring space is insufficient, and only 1 receiving chip can be integrated on the flexible board, and the COB scheme is adopted actively based on the application, so that the receiving electric chip is integrated on the flexible board, the receiving electric chip is prevented from being integrated on the circuit board, and the two transimpedance amplifiers can be integrated on the flexible board, the problem that the receiving chip is integrated on the circuit board is solved, so that a large amount of space is saved for the circuit board, the distance between a receiving channel and a transmitting channel on the circuit board is increased, and the problem of circuit crosstalk between the receiving channel and the transmitting channel is fundamentally solved.

The optical module provided by the embodiment of the application, especially for the high-speed 200G optical module transceiver, 8 channels are provided, the scheme of integrating the transimpedance amplifier by adopting the external flexible board is adopted, the integrated receiving electric chip on the circuit board is avoided, the layout of the transmitting chip and the receiving chip is avoided to be compact under the condition that the space requirement of the circuit board is not increased, the distance between the receiving channel and the transmitting channel is separated in space by the external flexible board, the shell for packaging the optical receiving assembly plays an isolation role on the electric signal of the transimpedance amplifier in the shell, the electric signal of the transimpedance amplifier is prevented from being influenced by the electric signal of the optical transmitting assembly, and the problems of the circuit crosstalk of the optical module are fundamentally solved by means of space isolation, position isolation, laminated structure optimization and the like.

It should be noted that, in this specification, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a circuit structure, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such circuit structure, article, or apparatus. Without further limitation, the statement "comprises" or "comprising" a … … "does not exclude that an additional identical element is present in a circuit structure, article or apparatus that comprises the element.

Other embodiments of the present application will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure of the invention herein. This application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the application and including such departures from the present disclosure as come within known or customary practice within the art to which the application pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the application being indicated by the following claims.

The above-described embodiments of the present application are not intended to limit the scope of the present application.

Claims

1. An optical module, comprising:

a circuit board;

the light emitting assembly is arranged on the circuit board and is used for emitting light signals;

an optical receiving assembly spatially separated from the optical transmitting assembly for receiving an optical signal from outside the optical module;

one end of the flexible board is fixed on the circuit board, and the other end of the flexible board extends into the light receiving assembly; for connecting the light receiving assembly with the circuit board;

wherein the light receiving assembly comprises:

the shell comprises an encapsulation shell and a cover plate pressed on the encapsulation shell, a first slot is formed in a side plate, adjacent to the cover plate, of the encapsulation shell, a mounting groove is formed in a bottom plate of the encapsulation shell, the bottom surface of the mounting groove is recessed in the bottom plate of the encapsulation shell, the bottom surface of the mounting groove is parallel to the bottom surface of the first slot, and the flexible plate is inserted into the mounting groove through the first slot; a second slot is arranged on the side plate opposite to the side plate where the first slot is arranged;

the light receiving device is inserted into the shell through the second slot, one end of the light receiving device comprises a detector and an array waveguide grating, the detector is arranged on the surface of the flexible board inserted into the shell, the output waveguide end of the array waveguide grating is positioned above the mounting slot, the photosensitive surface of the detector faces the output waveguide end of the array waveguide grating, and the detector is coupled and connected with the array waveguide grating; the output waveguide end of the array waveguide grating reflects the transmitted optical signals to the photosensitive surface of the detector so that the detector receives the optical signals of the external optical fibers;

2. The light module of claim 1 wherein a substrate is disposed within the housing, the substrate being positioned between the flexible board and a floor of the mounting slot; for supporting a flexible board inserted into the housing.

3. The light module of claim 1 wherein the flexible board is on a different side of the circuit board than the light emitting assembly.

4. The light module of claim 1 wherein the flexible board is on the same side of the circuit board as the light emitting assembly.

5. The optical module according to claim 1, wherein when a plurality of transimpedance amplifiers are provided on a surface of the flexible board inserted into the housing, a plurality of second slits are provided side by side on a side plate opposite to the side plate on which the first slits are provided, and a plurality of light receiving devices are inserted into the housing through the plurality of second slits.

6. The optical module according to claim 5, wherein when a plurality of light receiving devices are provided in the housing, the optical module is provided with a plurality of light emitting modules, and the plurality of light emitting modules are electrically connected to the circuit board, respectively.

7. The light module of claim 1 wherein the side plate of the housing connecting the first slot and the side plate of the second slot is provided with a viewing aperture, the viewing aperture being positioned to correspond to an inner wall of the mounting slot.

8. The optical module according to claim 1, wherein a wiring layer is provided on a side of the flexible board facing the circuit board, and a plurality of transimpedance amplifiers are connected to the circuit board through the wiring layer;

and a power supply wiring layer is arranged below the wiring layer, and the power supply wiring layer is arranged on one side of the transimpedance amplifier.

9. An optical module, comprising:

a circuit board;

wherein the light receiving assembly comprises:

the base plate is arranged in the shell and is positioned between the flexible plate and the bottom plate of the mounting groove; a flexible board for supporting insertion into the housing;

10. The optical module according to claim 9, wherein when a plurality of light receiving devices are provided in the housing, a plurality of mounting holes are provided side by side on the flexible board inserted into the housing, and a plurality of the transimpedance amplifiers are mounted on the surface of the substrate through the plurality of the mounting holes.