CN111061019A

CN111061019A - Optical module

Info

Publication number: CN111061019A
Application number: CN201911216155.8A
Authority: CN
Inventors: 金虎山
Original assignee: Hisense Broadband Multimedia Technology Co Ltd
Current assignee: Hisense Broadband Multimedia Technology Co Ltd
Priority date: 2019-12-02
Filing date: 2019-12-02
Publication date: 2020-04-24

Abstract

The optical module provided by the application comprises a circuit board provided with a signal circuit and used for providing signal electric connection. The circuit board can provide electric energy for the light emission sub-module and the light receiving sub-module through the signal circuit, so that the circuit board can realize corresponding functions. The light emission secondary module is connected with an external optical fiber through a light emission optical fiber and an optical fiber array connector, and is used for outputting the generated optical signal to the external optical fiber. The light receiving sub-module is connected with the external optical fiber through the incident optical fiber and used for receiving external optical signals. When the external optical fiber is inserted into the optical module, the external optical fiber is in butt joint with the incident optical fiber, and then optical signals input by the external light source are input into the optical receiving sub-module through the external optical fiber and the incident optical fiber. Because the external optical fiber adopts the single mode optical fiber, the incident optical fiber is the few-mode optical fiber or the multimode optical fiber, and the core diameter of the external optical fiber is smaller than that of the incident optical fiber, the optical signal output by the external optical fiber can be transmitted into the incident optical fiber as much as possible.

Description

Optical module

Technical Field

The embodiment of the application relates to the optical communication technology. And more particularly, to a light module.

Background

An optical module generally refers to an integrated module for photoelectric conversion, which is generally packaged by a transmitting part, a receiving part and a Printed Circuit Board (PCB) for photoelectric signal conversion. In the photoelectric signal conversion process, after receiving an optical signal transmitted by an external optical fiber, a receiving part converts the optical signal into an electric signal and transmits the electric signal to an upper computer through a printed circuit board; after receiving the electric signal transmitted by the upper computer, the transmitting part converts the electric signal into an optical signal and emits the optical signal through a corresponding optical fiber. The optical module receives the intensity of the optical signal input into the external optical fiber or the intensity of the optical signal input into the external optical fiber by the optical module directly influences the quality of optical fiber communication.

In general, an optical module interfaces an optical fiber (also referred to as an internal fiber in this embodiment) inside the optical module with an external optical fiber through an optical interface to realize communication with the external optical fiber. Specifically, the optical module is configured to interface an internal optical fiber with an external optical fiber through an input optical interface, so as to transmit an optical signal transmitted by the external optical fiber to the photodetector through the internal optical fiber. The photodetector photoelectrically converts the received optical signal. Or the optical signal sent by the optical chip in the optical module is coupled to the optical fiber adapter after passing through the lens. The optical fiber adapter is connected with an output optical interface of the optical module through another internal optical fiber so as to transmit the received optical signal to an external optical fiber connected with the internal optical fiber through another internal optical fiber.

The internal optical fibers connected with the input optical interface and the output optical interface of the traditional glazing module are single-mode optical fibers, the core diameter of each single-mode optical fiber is very small, and the external optical fibers are single-mode optical fibers generally. Therefore, at the joint of the internal optical fiber and the external optical fiber, the optical fiber axis is dislocated, which directly causes the loss of the optical signal.

Disclosure of Invention

The first optical module and the optical network device in the embodiments of the present application solve technical problems in the prior art.

A first aspect of an embodiment of the present application shows an optical module, including:

a circuit board having a signal circuit for providing a signal electrical connection;

the optical transmitter submodule is connected with the signal circuit of the circuit board and used for generating an optical signal;

the optical receiving sub-module is connected with the signal circuit of the circuit board and used for converting an external optical signal into an electric signal and outputting the electric signal through the signal circuit;

the transmitting optical fiber is connected with the optical transmitter optical subassembly at the light inlet end and is used for transmitting optical signals generated by the optical transmitter optical subassembly;

and the light outlet end of the incident optical fiber is connected with the light receiving submodule and is used for transmitting an external optical signal to the light receiving submodule.

The optical module that this application provided includes circuit board, optical transmit sub-module, optical receive sub-module, launching fiber and incident fiber. The circuit board has a signal circuit for providing a signal electrical connection. The circuit board can provide electric energy for the light emission sub-module and the light receiving sub-module through the signal circuit, so that the circuit board can realize corresponding functions. The tosa may be connected to an external optical fiber through a transmission optical fiber for outputting the generated optical signal to the external optical fiber. The light receiving sub-module can realize the connection with the external optical fiber through the incident optical fiber and is used for receiving the external optical signal input by the external optical fiber. When the external optical fiber is inserted into the optical module, the external optical fiber is in butt joint with the incident optical fiber, and therefore an optical signal input by an external light source enters the light receiving sub-module through the external optical fiber and the incident optical fiber. Generally, the external optical fiber is a single-mode optical fiber, and the core diameter of the external optical fiber is smaller than that of the incident optical fiber in the application, so that the optical signal output by the external optical fiber can be transmitted into the incident optical fiber as much as possible, thereby reducing the loss in the optical signal transmission process and finally improving the sensitivity of the whole module. In addition, since the core diameter of the incident optical fiber is larger than that of the external optical fiber, even if there is a certain deviation between the axis of the external optical fiber and the axis of the incident optical fiber during the assembly process, the deviation can be ignored with respect to the core diameter of the incident optical fiber, and based on this, it is proved again that the sensitivity of the optical module shown in the present application is good.

The launch fiber in this embodiment is a single mode fiber. The transmitting optical fiber is used for outputting the optical signals transmitted by the optical transmitter sub-assembly through the external optical fiber. Outside optic fibre adopts for single mode fiber, if set up emission optic fibre as multimode fiber or few mode optic fibre, emission optic fibre's core footpath is greater than outside optic fibre's core footpath, even under outside optic fibre and the accurate alignment meeting's of emission optic fibre the condition, also can have optical signal's loss in outside optic fibre and emission optic fibre butt joint department, on this basis, will launch optic fibre in this application and set up to single mode fiber.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other 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 invention;

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

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

FIG. 6 is a schematic diagram of an assembly of a circuit board and an external optical fiber according to an embodiment of the present invention;

FIG. 7a is a schematic view of an assembly of optical fibers according to an embodiment of the present invention;

FIG. 7b is a schematic view of an assembly of optical fibers according to an embodiment of the present invention;

FIG. 8 is a schematic diagram of an incident fiber stub provided in an embodiment of the present invention;

fig. 9 is a schematic diagram of an optical path when the external optical fiber of the present embodiment is butted with the incident optical fiber.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Optical communication enables signals to be transmitted using two different carriers, electrical and optical. Optical signals carrying information are transmitted in the optical waveguide for optical fiber communication, and the information transmission with low cost and low loss can be realized by utilizing the passive transmission characteristic of light in the optical waveguide such as the optical fiber; the information processing devices such as computers use electrical signals, which requires the interconversion between electrical signals and optical signals in the optical fiber communication system.

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 an optical network unit 100, an optical module 200, an optical fiber 101, and a 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 completed by the optical network unit 100 having the optical module 200.

An optical port of the optical module 200 is connected with the optical fiber 101 and establishes bidirectional optical signal connection with the optical fiber;

the electrical port of the optical module 200 is accessed into the optical network unit 100, and establishes bidirectional electrical signal connection with the optical network unit;

the optical module realizes the mutual conversion of optical signals and electric signals, thereby realizing the connection between the optical fiber 101 and the optical network unit 100;

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 unit 100, and the electrical signal from the optical network unit 100 is converted into an optical signal by the optical module and input to the optical fiber 101. The optical module 200 is a tool for realizing the mutual conversion of the photoelectric signals, and has no function of processing data, and in the photoelectric conversion process, the carrier of the information is converted between the light and the electricity, but the information itself is not changed.

The optical network unit 100 has an optical module interface 102, which is used for accessing the optical module 200 and establishing a bidirectional electrical signal connection with the optical module 200;

the optical network unit 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 with the network cable 103 through an optical network unit;

specifically, the optical network unit 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 unit serves as an upper computer of the optical module to monitor the operation of the optical module.

To this end, the remote server establishes a bidirectional signal transmission channel with the local information processing device sequentially through the optical fiber 101, the optical module 200, the optical network unit 100, and the network cable 103.

Common information processing apparatuses include routers, switches, electronic computers, and the like;

the optical network unit 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 (OLT) and the like.

Fig. 2 is a schematic diagram of an optical network unit structure. As shown in fig. 2, the optical network unit 100 includes a circuit board 105, and a cage 106 is disposed on a surface of the circuit board 105; an electrical connector connected to the circuit board 105 is provided in the cage 106, and is used for connecting an electrical port of an optical module such as a gold finger; the cage 106 is provided with a heat sink 107, and the heat sink 107 has a convex structure such as a fin for increasing a heat radiation area.

The optical module 200 is inserted into the optical network unit 100, specifically, an electrical port of the optical module is inserted into an electrical connector in the cage 106, and an optical port of the optical module is connected to the optical fiber 101.

The cage 106 is located on the circuit board 105 of the optical network unit 100, and the electrical connectors on the circuit board 105 are wrapped in the cage; the optical module is inserted into the cage, the cage fixes the optical module, and heat generated by the optical module is conducted to the cage through the optical module housing and finally diffused through the heat sink 107 on the cage.

Fig. 3 is a schematic diagram of an optical module structure according to an embodiment of the present invention, and fig. 4 is an exploded schematic diagram of an optical module structure according to an embodiment of the present invention, as shown in fig. 3 and fig. 4, an optical module 200 according to an embodiment of the present invention includes an upper housing 201, a lower housing 202, an unlocking handle 203, a circuit board 300, a light emission sub-module 400, a light reception sub-module 500, and an optical fiber array connector 600.

The upper shell 201 and the lower shell 202 form a package cavity with two ports, specifically two ports (204, 205) in the same direction, or two ports in different directions; one of the ports is an electrical port 204 which is used for being inserted into an upper computer such as an optical network unit; the other port is an optical port 205 for connecting an external optical fiber 101; the optoelectronic devices such as the circuit board 300, the transmitter sub-module 400, and the receiver sub-module 500 are disposed in the package cavity formed by the upper and lower shells.

The upper shell and the lower shell are made of metal materials generally, so that electromagnetic shielding and heat dissipation are facilitated; the assembly mode that adopts upper housing, casing combination down is convenient for install devices such as circuit board in the casing, generally can not make the casing of optical module structure as an organic whole, like this when devices such as assembly circuit board, locating part, heat dissipation and electromagnetic shield structure are not convenient for install, are unfavorable for production automation.

The unlocking handle 203 is positioned on the outer wall of the packaging cavity/lower shell 202, and the tail end of the unlocking handle is pulled to enable the unlocking handle to move relatively on the surface of the outer wall; when the optical module is inserted into the upper computer, the cage 106 is clamped by the unlocking handle 203, so that the optical module is fixed in the upper computer; by pulling the unlocking handle, the engagement between the optical module 200 and the cage 106 is released, and the optical module can be pulled out from the upper computer.

The circuit board 300 is located in a packaging cavity formed by the upper shell and the shell, the circuit board 300 is electrically connected with the light-emitting sub-module 400 and the light-receiving sub-module 500 respectively, and the circuit board is provided with chips, capacitors, resistors and other electric devices. Selecting corresponding chips according to the requirements of products, wherein common chips comprise a microprocessor MCU, a clock data recovery chip CDR, a laser driving chip, a transimpedance amplifier TIA chip, a limiting amplifier LA chip, a power management chip and the like;

the transimpedance amplifier is closely associated with the optical detection chip, and the transimpedance amplifier and the optical detection chip can be packaged together by a part of products, such as in the same TO (TO optical) tube shell or the same shell; the optical detection chip and the transimpedance amplifier can be separately packaged, and the transimpedance amplifier is arranged on the circuit board.

The chip on the circuit board 300 may be a multifunctional integrated chip, for example, a laser driver chip and an MCU chip are integrated into one chip, or a laser driver chip, a limiting amplifier chip and an MCU chip are integrated into one chip, and the chip is an integrated circuit, but the functions of the circuits do not disappear due to the integration, and only the circuit appears and changes, and the chip still has the circuit form. Therefore, when the circuit board is provided with three independent chips, namely, the MCU, the laser driver chip and the limiting amplifier chip, the scheme is equivalent to that when the circuit board 300 is provided with a single chip with three functions in one.

The surface of the end part of the circuit board 300 is provided with a golden finger, the golden finger consists of one pin which is mutually independent, the circuit board is inserted into an electric connector in the cage, and the golden finger is in conductive connection with a clamping elastic sheet in the electric connector; the golden fingers can be arranged on the surface of one side of the circuit board, and the golden fingers are generally arranged on the upper surface and the lower surface of the circuit board in consideration of the large requirement on the number of pins; the golden finger is used for establishing electrical connection with the upper computer, and the specific electrical connection can be power supply, grounding, I2C signals, communication data signals and the like.

The optical module further includes a transmitter optical subassembly and a receiver optical subassembly, which may be collectively referred to as an optical subassembly. As shown in fig. 4, the optical module provided in the embodiment of the present invention includes a tosa 400 and a rosa 500, the tosa 400 is located at an edge of the circuit board 300, and the tosa 400 and the rosa 500 are arranged on the surface of the circuit board 300 in a staggered manner, which is beneficial to achieving a better electromagnetic shielding effect.

The tosa 400 is disposed on a surface of the circuit board 300. in another conventional package, the tosa is physically separated from the circuit board and electrically connected to the pcb through a flexible board.

The tosa 400 is provided with a laser component including a laser chip, a metalized ceramic, and an optical lens. The laser chip is arranged on the surface of the metallized ceramic, a circuit pattern is formed on the surface of the metallized ceramic, power can be supplied to the laser chip, and meanwhile the metallized ceramic has better heat conduction performance and can be used as a heat sink of the laser chip for heat dissipation; the laser chip becomes a preferred light source for optical module and even optical fiber transmission by better single-wavelength characteristic and better wavelength tuning characteristic; even if a special optical communication system adopts the light source, the characteristics and chip structure of the light source are greatly different from those of laser, so that the optical module adopting laser and the optical module adopting other light sources have great technical difference, and a person skilled in the art generally does not consider that the two types of optical modules can give technical inspiration to each other.

The optical lens functions to condense light, and light emitted from the laser chip is generally in a divergent state, so that convergence processing is required for facilitating subsequent optical path design and light coupling into an optical fiber. In general, the convergence is to converge divergent light into parallel light, and converge divergent light and parallel light into convergent light.

The tosa may further include a semiconductor cooler TEC according to the transmission design and the characteristics of the laser chip. The TEC is directly or indirectly arranged on the bottom surface of the cavity of the light emission submodule, the metallized ceramic is arranged on the surface of the TEC, and the TEC is used for balancing heat to maintain the set working temperature of the laser chip.

The transmitter optical subassembly module is provided with a packaging structure for packaging laser chips and the like, and the existing packaging structure comprises a coaxial packaging TO-CAN, a silicon optical packaging, a chip-on-board LENS assembly packaging COB-LENS and a micro-optical XMD packaging. The package is further divided into hermetic package and non-hermetic package, which provides a stable and reliable working environment for the laser chip on one hand and forms external electrical connection and optical output on the other hand.

The rosa 500 is disposed on the surface of the circuit board 300, and in another common packaging method, the rosa is physically separated from the circuit board and electrically connected through a flexible board.

The light receiving sub-module 500 is provided with a laser component, and the laser component includes a photodetector, an optical lens, and a metallized ceramic. The photoelectric detector is arranged on the surface of the metallized ceramic, the circuit pattern is formed on the surface of the metallized ceramic, the power can be supplied to the photoelectric detector, and meanwhile, the metallized ceramic has better heat conduction performance and can be used as a heat sink of the photoelectric detector for heat dissipation. The optical lens functions to condense light, and an optical signal input from the optical fiber is in a divergent state. A common convergence is to converge diverging light into converging light. The optical receive sub-module may also include a semiconductor cooler TEC depending on the transmission design and the characteristics of the photodetector. The TEC is directly or indirectly arranged on the bottom surface of the cavity of the light receiving submodule, the metallized ceramic is arranged on the surface of the TEC, and the TEC is used for balancing heat to maintain the set working temperature of the laser chip.

The rosa 500 has a package structure to package the components such as the photodetector, the optical lens, and the metallized ceramic. According to product design and process, the optical module adopts different packages to manufacture the optical receive sub-module, and the structure and the process are different technical directions, and those skilled in the art know that although the purpose realized by different packages has certain same points, different packages belong to different technical routes, and different packaging technologies do not give technical inspiration to each other.

And an optical fiber 401 having an optical input end connected to the tosa 400 and an optical output end butted with an external optical fiber (not shown) through an optical fiber array connector 600, for transmitting an optical signal generated by the tosa 400.

An optical fiber 501, an optical output end of which is connected to the optical receive sub-module 500, and an optical input end of which is butted with an external optical fiber (not shown in the figure) through an optical fiber array connector 600, is used for transmitting an external optical signal to the optical receive sub-module 500.

The optical fiber array connector 600 has one port into which the emitting optical fiber 401 and the incident optical fiber 501 can be inserted, and another port into which an external optical fiber (not shown) can be inserted, for realizing the butt joint of the emitting optical fiber 401 and the external optical fiber, and the butt joint of the incident optical fiber 501 and the external optical fiber.

The optical fiber array connector 600 is assembled and fixed with the clamping groove 206 on the lower shell 202; specifically, the fiber array connector 600 is fixed to the lower housing 202 by placing the fiber array connector 600 in the card slot 206.

The card slot 206 divides the lower case into two regions, the circuit board 300 is disposed in one of the regions, and a convex column is formed on the surface of the lower case of the region to fix the circuit board 300; the tosa is fixed with the circuit board 300, and the tosa 400 and the rosa 500 are fixed on the lower housing by fixing the circuit board 300; of course, the tosa 400 and the rosa 500 may be directly fixed to the lower case without being indirectly fixed through the circuit board 300; fiber array connector 600 is disposed in another of the regions.

Fig. 5 is a schematic diagram illustrating an assembly structure of a circuit board and a fiber array connector according to an embodiment of the present disclosure. As shown in fig. 5, the circuit board is provided with an tosa 400, an incident fiber 501, fiber adapters (402, 502), an emitting fiber 401, and an incident fiber 501.

The launch fiber 401 has an optical input end connected to the launch sub-module 400 via a fiber adapter 402. The specific connection process is as follows: the light input end of the transmitting optical fiber 401 is connected to the optical fiber adapter 402, and the optical fiber adapter 402 is inserted into the tosa 400 to assemble the transmitting optical fiber 401 and the tosa 400, so as to output an optical signal generated by the tosa 400.

The incident optical fiber 501 and the light outlet end are connected with the optical receive sub-module 500 through an optical fiber adapter 502. The specific connection process is as follows: the light outlet end of the incident optical fiber 501 is connected with the optical fiber adapter 502, and the optical fiber adapter 502 is inserted into the optical receiving sub-module 500, so that the incident optical fiber 501 and the optical receiving sub-module 500 are assembled, and further, the transmission of external optical signals is realized.

One port of the optical fiber array connector 600 allows the light-out end of the transmitting optical fiber 401 and the light-in end of the incident optical fiber 501 to pass through, and the other port allows an external optical fiber (not shown in the figure) to pass through, so that the light-out end of the transmitting optical fiber 401 can be butted with the external optical fiber (not shown in the figure) to realize optical communication between the tosa 400 and an external device, and meanwhile, the light-in end of the incident optical fiber 501 can also be butted with the external optical fiber (not shown in the figure) through the optical fiber array connector 600 to realize optical communication between the tosa 500 and the external device.

The distance between the fiber array connector 600 and the tosa 400 is relatively fixed, so the size of the emission fiber 401 should meet the distance requirement between the tosa 400 and the fiber array connector 600, and considering the existence of process error, the size of the fiber is always too short or too long in practice. The connection cannot be realized due to the fact that the optical fibers are too short; the optical fiber is bent when it is too long, and the bent optical fiber is not favorable for the propagation of optical signals.

Based on the above problems, in the optical module of this embodiment, a through hole (not shown in the figure) is formed in a side wall of the tosa 400, the optical fiber adapter 402 can extend into the through hole to fix the tosa 400, and this assembling structure design can enable the optical fiber adapter 402 to move forward and backward in the through hole, so that the size of the emission optical fiber 401 between the tosa 400 and the fiber array connector 600 can be adjusted, and when the emission optical fiber 401 is short, the emission optical fiber 401 adapter can be moved in the through hole toward the fiber array connector 600 to meet the requirement of the connection size; when the optical fiber is long, the optical fiber adapter 402 can be moved in the through hole toward the tosa 400 to straighten the optical fiber and avoid bending the launch optical fiber 401.

Similarly, a through hole (not shown in the figure) may be formed in a side wall of the light receiving sub-module 500, and the optical fiber adapter 502 may extend into the through hole to fix the light receiving sub-module 500, and this assembling structure design may enable the optical fiber adapter 502 to move back and forth in the through hole, so as to adjust the size of the incident optical fiber 501 between the light receiving sub-module 500 and the optical fiber array connector 600, and when the incident optical fiber 501 is short, the incident optical fiber 501 adapter may move in the through hole toward the optical fiber array connector 600 to meet the requirement of the connection size; when the optical fiber is long, the optical fiber adapter 502 can be moved in the through hole toward the rosa 500 to straighten the optical fiber and prevent the incident optical fiber 501 from bending.

The optical module shown in this embodiment realizes connection between devices (optical receive sub-module and optical transmit sub-module) mounted on a circuit board and an external optical fiber through an optical fiber array connector. The connection process of the device mounted on the circuit board and the external optical fiber will be described in detail below.

FIG. 6 is a diagram illustrating the assembly of a circuit board, fiber array connectors, and external optical fibers, according to one embodiment. It can be seen from fig. 6 that the circuit board is provided with an optical transmit sub-assembly 400, an optical receive sub-assembly 500, optical fiber adapters (402, 502), a transmitting optical fiber 401 and an incident optical fiber 501.

The optical fiber array connector 600 is provided with a substrate 601, and a first port 602 and a second port 603 which are mutually communicated are arranged on two opposite end faces of the substrate 601. The first port 602 allows the light-out end of the launching fiber 401 and the light-in end of the incident fiber 501 to be inserted; the second port 603 allows for insertion of an external optical fiber 703, and the interfacing of the emitting optical fiber 401 with the external optical fiber 703 and the interfacing of the incident optical fiber 501 with the external optical fiber 703 can be accomplished inside the matrix 601.

The light inlet end of the transmitting optical fiber 401 is connected with the optical fiber adapter 402, the optical fiber adapter 402 is inserted into the through hole of the tosa 400, so that the transmitting optical fiber 401 is connected with the tosa 400, and further, the optical signal generated by the tosa 400 can be transmitted through the transmitting optical fiber 401. The light exit end of the emission fiber 401 can be inserted into the first port 602 of the fiber array connector 600. When the external optical fiber 703 is inserted into the second port 603 of the optical fiber array connector 600, the emission optical fiber 401 is butted with the external optical fiber 703 inside the optical fiber array connector 600, and the emission optical fiber 401 can output the optical signal received from the tosa 400 through the external optical fiber 703.

The tosa 400 is connected to the light input end of the transmitting fiber 401 to output the generated optical signal through the transmitting fiber 401.

The light outlet end of the incident optical fiber 501 is connected with the optical fiber adapter 502, the optical fiber adapter 502 is inserted into the through hole of the optical receive sub-module 500, so that the incident optical fiber 501 and the optical receive sub-module 500 are assembled, and the incident optical fiber 501 transmits the received optical signal to the optical receive sub-module 500; the light input end of the incident optical fiber 501 can be inserted into the first port 602 of the optical fiber array connector 600. When the external optical fiber 703 and the optical fiber plug 701 are inserted into the second port 603 of the optical fiber array connector 600, the incident optical fiber 501 and the external optical fiber 703 are butted inside the optical fiber array connector 600, and then the incident optical fiber 501 can transmit the received optical signal transmitted by the external optical fiber to the optical receive sub-module 500.

The optical receive sub-module 500 is connected to the light output end of the incident optical fiber 501, so as to perform photoelectric conversion on the optical signal transmitted by the incident optical fiber 501.

In addition, external optical fibers 703 may be inserted through the fiber optic plug 701 into the second port 603 of the fiber array connector 600. To secure the optical fiber plug 701, the second port 603 of the optical fiber array connector 600 may be contoured to match the cross-section of the optical fiber plug 701, so that the optical fiber plug 701 can be secured within the second port 603.

In a possible embodiment, the fiber optic plug 701 may be provided with a stop protrusion 702, and correspondingly, the second port 603 is provided with a space 606 for receiving the stop protrusion 702. When the optical fiber plug 701 is inserted into the second port 603, the relative positions of the optical fiber array connector 600 and the optical fiber plug 701 can be fixed by clamping the limiting protrusion 702 and the space 606, so that the butt joint of the incident optical fiber 501 and the external optical fiber 703 and the butt joint of the emission optical fiber 401 and the external optical fiber 703 are facilitated.

Optionally, two opposite ends of the second port 603 may be provided with locking members (604, 605), a distance between the locking members (604, 605) is smaller than a width of the optical fiber plug 701 in the same direction, when the optical fiber plug 701 is inserted into the second port 603, the locking members (604, 605) elastically deform and generate an elastic acting force, and the elastic acting force plays a role in fixing the optical fiber plug 701, so as to facilitate fixing of the relative position of the optical fiber array connector 600 and the optical fiber plug 701, further facilitate the butt joint of the incident optical fiber 501 and the external optical fiber 703, and the butt joint of the emission optical fiber 401 and the external optical fiber 703.

Fig. 7a is a schematic view of an assembly structure of an internal optical fiber (including an emitting optical fiber and an incident optical fiber) of an optical module and an external optical fiber of the optical module. As can be seen from fig. 7a, the core diameter of the emitting fiber 401 of the optical module of the present application is equal to the core diameter of the external fiber 703, and the core diameter of the incident fiber 501 is greater than or equal to the core diameter of the external fiber 703. The external optical fiber 703 in the optical module industry mostly adopts a single mode optical fiber, in this application, the transmitting optical fiber 401 adopts a single mode optical fiber, and the incident optical fiber 501 adopts a multimode optical fiber or a few-mode optical fiber. Wherein the core diameter of the single-mode optical fiber is 8-10 μm, the core diameter of the few-mode optical fiber is 15-30 μm, and the core diameter of the multi-mode optical fiber is 50-100 μm.

When the external optical fiber 703 is inserted into the second port of the optical fiber array connector 600 through the optical fiber plug 701, the external optical fiber 703 is butted with the incident optical fiber 501 inside the optical fiber array connector 600, so that an optical signal input by an external light source is input to the optical receiving sub-module 500 through the external optical fiber 703 and the incident optical fiber 501. Since the core diameter of the external optical fiber 703 is smaller than that of the incident optical fiber 501, the optical signal output from the external optical fiber 703 is transmitted into the incident optical fiber 501 as much as possible; even if the external optical fiber 703 and the incident optical fiber 501 are not precisely aligned during the assembling process, (specifically, the assembling schematic can refer to fig. 7b), it can be ensured that the optical signal output by the external optical fiber 703 is transmitted to the incident optical fiber 501 as much as possible, and the loss during the optical signal transmission process is reduced.

In addition, the technical scheme shown in the embodiment can improve the sensitivity of the optical module. As is known, the core diameter of a single mode fiber is only 8 μm to 10 μm, and the core diameter of a multimode fiber is 50 μm to 100 μm. In particular, when the external optical fiber is butted with the incident optical fiber, if there is a 1 μm deviation between the external optical fiber and the incident optical fiber during installation, the 1 μm deviation is 1% to 2% relative to a core diameter of 50 μm to 100 μm, and the relative deviation is negligible. However, if the incident fiber is a single mode fiber, the relative deviation of 1 μm is 10% to 12.5% with respect to the core diameter of 8 μm to 10 μm, which is large. Therefore, the technical scheme of the application is adopted to set the incident optical fiber as the multimode optical fiber, so that the sensitivity of the optical module can be improved.

Meanwhile, the emitting fiber 401 in this embodiment is a single mode fiber, and the emitting fiber is used to output the optical signal emitted by the laser chip through an external fiber. Since the external optical fiber is a single mode optical fiber, the emitting optical fiber 401 is configured as a multimode optical fiber or a few-mode optical fiber. The core diameter of the launch fiber 401 is larger than the core diameter of the external fiber 703, and even with precise alignment of the external fiber 703 with the launch fiber 401, there is a loss of optical signal at the interface of the external fiber with the launch fiber 401. Based on this, the technical solution shown in this embodiment is to configure the transmitting fiber 401 as a single mode fiber.

As can be seen, in the optical module shown in this embodiment, the incident optical fiber 501 is a few-mode optical fiber or a multimode optical fiber with a larger core diameter, so as to reduce loss in the optical signal transmission process, and finally improve the sensitivity performance of the whole module. However, the incident optical fiber 501 has a large core diameter, and the optical spot of the optical signal output from the incident optical fiber 501 increases accordingly. Based on this, a converging lens may be disposed between the output end of the incident optical fiber 501 and the photodetector. The converging lens is arranged between the light-emitting surface of the incident optical fiber 501 and the photoelectric detector, so that light spots formed on the photoelectric detector by optical signals output by the incident optical fiber 501 are smaller than the photosensitive surface of the photoelectric detector, the loss in the optical signal transmission process is further reduced, and the sensitivity of the whole module is improved.

The optical fiber is flexible and is not easy to be fixed with the external optical fiber in a high-precision position, so that the optical fiber ferrule is designed in the embodiment. The optical fiber inserting core is made of a hard material capable of realizing high-precision processing to wrap the optical fiber. The structure of the optical fiber ferrule will be described below by taking the optical fiber ferrule at the receiving end as an example. Fig. 8 is a schematic diagram of an incident fiber stub including a wrapping material 503 and an incident fiber 501.

The wrapping material 503 is formed by processing a material which is hard and can realize high-precision processing, and the fixing of the wrapping material 503 realizes the fixing of the incident optical fiber 501. Specifically, the incident optical fiber ferrule can be formed by wrapping an incident optical fiber by a ceramic material, the incident optical fiber is used for guiding light, the ceramic has high processing precision, and high-precision position alignment can be realized.

And the incident optical fiber 501 is arranged inside the wrapping material 503, and the incident optical fiber 501 is fixed by fixing the wrapping material 503. The fixing direction of the incident optical fiber 501 in the incident optical fiber ferrule is limited by the wrapping material 503, the wrapping material 503 is generally processed into a cylinder, a linear through hole is arranged in the center of the wrapping material 503, and the incident optical fiber is inserted into the through hole of the wrapping material 503 to realize fixing, so that the incident optical fiber is straightly fixed in the wrapping material 503.

The transmitting optical fiber ferrule of the transmitting end is similar to the incident optical fiber ferrule of the receiving end in structure, and the description is omitted here.

The optical signal propagates inside the external optical fiber along the broken line path, and is refracted at the butt end face of the external optical fiber and the incident optical fiber (also called as the incident surface of the incident optical fiber), if the refraction angle is large enough, the total reflection occurs at the butt end face, and the totally reflected optical signal returns along the original optical path, which causes the loss of the optical signal. In order to prevent the optical signal from returning along the original optical path, it is necessary to minimize the refraction angle at the mating end surface when designing the optical path. To achieve a reduction in the angle of refraction at the butt end face, the corresponding angle of incidence needs to be reduced. In order to achieve the purpose of reducing the incident angle, the scheme shown in the embodiment of the present application grinds the incident surface of the incident optical fiber into an inclined surface. The specific implementation mode can wrap the incident optical fiber in the ceramic to form the incident surface of the incident optical fiber insertion core, and the incident surface of the incident optical fiber is ground into an inclined surface correspondingly.

The following describes in detail the technical solution shown in the embodiments of the present application with reference to specific examples to reduce loss in the optical signal transmission process. Fig. 9 is a schematic diagram of an optical path when the external optical fiber of the present embodiment is butted with the incident optical fiber. It can be seen that the incident surface of the incident optical fiber 501 is an inclined surface, the different inclination directions of the incident surface are only different view angles, the incident optical fiber 501 is a cylinder, and the different inclination directions of the inclined surface are seen by rotating the viewing angle. In order to prevent the reflected light from being reflected back to the external optical fiber 703 reversibly, the light incident surface of the incident optical fiber 501 is set to be an inclined surface in the present application. The light emitted by the external light source is totally emitted inside the external optical fiber and then enters the light incident surface of the incident optical fiber 501, because the light incident surface is an inclined surface, the incident angle a of the light signal on the light incident surface is small, and correspondingly, the refraction angle on the light incident surface is also small, so that the total reflection of the light signal on the light incident surface is not facilitated; therefore, the loss of the optical signal in the transmission process is reduced, and the sensitivity of the whole module is finally improved.

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

Claims

1. A light module, comprising:

the optical transmitter submodule is connected with the signal circuit and is used for generating an optical signal;

the optical receiving sub-module is connected with the signal circuit and used for converting the received external optical signal into an electric signal and outputting the electric signal through the signal circuit;

the transmitting optical fiber is connected with the optical transmitter optical subassembly at the light inlet end and is used for transmitting optical signals generated by the optical transmitter optical subassembly; the emission optical fiber is a single mode optical fiber;

and the light outlet end of the incident optical fiber is connected with the light receiving submodule and is used for transmitting the external optical signal to the light receiving submodule, and the core diameter of the incident optical fiber is larger than that of the transmitting optical fiber.

2. The optical module of claim 1, further comprising:

the optical fiber array connector is provided with a first port and a second port which are mutually communicated, the first port allows a light-emitting end of the emission optical fiber to pass through, and the second port allows an external optical fiber to pass through, so that the emission optical fiber is butted with the external optical fiber; the first port also allows the light-incoming end of the incident optical fiber to pass through, so as to realize the butt joint of the incident optical fiber and the external optical fiber.

3. The optical module according to claim 1, wherein the incident optical fiber is a few-mode optical fiber, and a core diameter of the few-mode optical fiber is 15 μm to 30 μm.

4. The optical module according to claim 1, wherein the incident optical fiber is a multimode optical fiber having a core diameter of 50 μm to 100 μm.

5. The optical module of claim 1, wherein the rosa comprises:

the photoelectric detector is used for converting the received external optical signal into an electric signal and outputting the electric signal to the circuit board;

and the converging lens is arranged between the light-emitting surface of the incident optical fiber and the photoelectric detector so as to realize that light spots formed on the photoelectric detector by optical signals output by the incident optical fiber are smaller than the photosensitive surface of the photoelectric detector.

6. The optical module of claim 1, wherein the light incident surface of the incident optical fiber is disposed obliquely with respect to the optical axis of the rosa to reduce an incident angle of an external optical signal on the light incident surface.

7. The optical module of claim 2, wherein the external optical fiber is inserted into the second port by a fiber optic plug;

and locking parts are arranged on two opposite end faces of the second port, and the distance between the two locking parts is smaller than the width of the optical fiber plug in the same direction.