CN113296199A

CN113296199A - Single-fiber bidirectional optical assembly and optical module

Info

Publication number: CN113296199A
Application number: CN202010107663.9A
Authority: CN
Inventors: 李志伟; 张为
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2020-02-21
Filing date: 2020-02-21
Publication date: 2021-08-24

Abstract

The invention is suitable for the technical field of communication, and provides a single-fiber bidirectional optical component and an optical module, wherein the single-fiber bidirectional optical component comprises an optical transmitting unit, an optical receiving unit and a planar optical waveguide chip; an optical transmission unit for transmitting an outgoing optical signal having a first wavelength; the light receiving unit is positioned below the planar optical waveguide chip and used for receiving an incident light signal with a second wavelength; the planar optical waveguide chip comprises a wave splitting and combining device, a reflecting surface, a first port and a second port, wherein the wave splitting and combining device is used for sending an emergent optical signal received by the first port out through the second port and sending an incident optical signal received by the second port to the optical receiving unit through the reflecting surface; the reflecting surface is arranged between the wave splitting and combining device and the light receiving unit and is used for reflecting the incident light signals passing through the wave splitting and combining device to the light receiving unit. The single-fiber bidirectional optical component provided by the invention has the advantages of small volume, simple structure and low cost, and can be applied to a high-speed communication network.

Description

Single-fiber bidirectional optical assembly and optical module

Technical Field

The invention relates to the technical field of optical communication, in particular to a single-fiber bidirectional optical component and an optical module.

Background

With the advancement of information-oriented processes and the demand of network applications, a single-fiber Bidirectional (BiDi) optical module is widely used in a communication network because one optical fiber resource can be saved, compared with a conventional two-fiber Bidirectional optical module. For a single-fiber bidirectional Optical module, the most core component is a single-fiber bidirectional Optical component (BOSA) integrated inside, and the BOSA integrates light emission and reception, so that bidirectional transmission of data can be realized by using one Optical fiber.

Currently, the commonly used BOSA is widely adopted in 50GE (english: Gigabit Ethernet, chinese: Gigabit Ethernet), especially in 25GE and below transmission rates, and when the transmission rate is increased to 100GE or higher, the rate is limited by the bandwidth constraint of the traditional device packaging method and the increase of the device packaging cost in a high-rate scene, and the implementation of a high-speed BOSA scheme is difficult, so that a new BOSA solution needs to be found.

Disclosure of Invention

The embodiment of the invention provides a single-fiber bidirectional optical module, aiming at solving the problems of low speed and high cost of the existing single-fiber bidirectional optical module.

In a first aspect, the present invention provides a single-fiber bidirectional optical component, including an optical transmitting unit, an optical receiving unit, and a planar optical waveguide chip; the optical transmitting unit is used for transmitting an emergent optical signal with a first wavelength; the light receiving unit is positioned below the planar optical waveguide chip and used for receiving an incident light signal with a second wavelength; the planar optical waveguide chip comprises a wave splitting and combining device, a reflecting surface, a first port and a second port, wherein the wave splitting and combining device is used for sending the emergent optical signals received by the first port out through the second port and sending the incident optical signals received by the second port to the optical receiving unit through the reflecting surface; the reflecting surface is arranged between the wave splitting and combining device and the light receiving unit and used for reflecting the incident light signals passing through the wave splitting and combining device to the light receiving unit.

In a possible implementation manner, n optical channels (n is greater than or equal to 1) are arranged in the planar optical waveguide chip and used for realizing transmission of n optical signals.

In another possible implementation, the first angle between the reflecting surface and the horizontal line is in a range of 30 degrees to 60 degrees.

In a possible implementation manner, the light receiving unit includes a light detector and a transimpedance amplifier, and both the light detector and the transimpedance amplifier are placed by being attached to a printed circuit board PCB; the optical detector is used for receiving the incident optical signal and converting the incident optical signal into an incident electric signal; the transimpedance amplifier is used for amplifying and outputting the incident electric signal.

In another possible implementation manner, the first included angle is 42 degrees, so that the incident light signal is incident on the photosensitive surface of the light detector approximately perpendicular to the PCB.

In a possible implementation manner, an antireflection film is plated on a plane below the reflecting surface, and the antireflection film is used for reducing the return loss of the incident light signal when the incident light signal is incident perpendicular to the PCB.

In another possible implementation manner, the light receiving unit is located 5-15 μm below the planar optical waveguide chip.

In a possible implementation manner, the splitting and combining device is an arrayed waveguide grating.

In another possible implementation manner, the demultiplexing and multiplexing device is a mach-zehnder modulator.

In a possible implementation manner, the single-fiber bidirectional optical component further comprises an optical fiber array, and the optical fiber array comprises 2n (n is more than or equal to 1) optical fiber channels.

In one possible implementation, the optical transmission unit includes n (n ≧ 1) lasers for simultaneously transmitting n outgoing optical signals having the first wavelength.

In another possible implementation manner, the optical fiber array and the planar optical waveguide chip are coupled by gluing or welding.

In a second aspect, the present invention provides a bidirectional optical module, including a light source driver, the bidirectional optical module and a signal processor as described in the first aspect and any possible implementation manner thereof, where the light source driver is configured to drive the bidirectional optical module to generate an outgoing light signal having a first wavelength; the single-fiber bidirectional optical component is used for generating and transmitting the emergent light signal, receiving an incident light signal with a second wavelength at the same time, and transmitting the incident light signal to the signal processor; and the signal processor is used for processing the incident electric signal converted from the incident optical signal.

In a possible implementation manner, the single-fiber bidirectional optical component, the light source driver and the signal processing unit are all placed on a printed circuit board PCB.

In another possible implementation manner, the single-fiber bidirectional optical component includes an optical transmitting unit, an optical receiving unit, and a planar optical waveguide chip, where the optical transmitting unit is connected to the planar optical waveguide through an optical fiber.

In a possible implementation manner, a reflection surface is provided on the planar optical waveguide chip, and is used for reflecting the received incident optical signal to the light receiving unit.

In a possible implementation manner, the light source driver is connected to the light sending unit through a driving circuit, and the driving circuit is located on the PCB.

In another possible implementation manner, the optical transmitting unit includes a plurality of lasers for simultaneously generating a plurality of paths of the outgoing optical signals; the light receiving unit comprises a light detector array and a transimpedance amplifier, the light detector array is provided with a plurality of light ports and is used for receiving a plurality of paths of incident light signals simultaneously and converting the plurality of paths of incident light signals into incident electric signals, and the transimpedance amplifier is used for amplifying the plurality of paths of incident electric signals.

In a possible implementation manner, an input end of the signal processing unit is connected to an output end of the transimpedance amplifier, and receives and processes the incident electric signal output from the transimpedance amplifier.

According to the single-fiber bidirectional optical module provided by the embodiment of the invention, the redesign and adjustment of an optical path are realized by adopting a method of combining the planar optical waveguide with the reflecting surface in the optical assembly, and the single-fiber bidirectional optical module and a COB packaging mode are combined together, so that the bandwidth limitation caused by the traditional packaging mode can be solved, the high-speed application of the single-fiber bidirectional optical module is realized, the cost can be effectively reduced through the COB packaging, and the size of the optical module is reduced.

Drawings

FIG. 1 is a schematic diagram of a current BOSA;

FIG. 2 is a schematic diagram of another current BOSA configuration;

FIG. 3 is a package format used by the BOSA shown in FIGS. 1 and 2;

fig. 4 is a schematic diagram of a single-channel BOSA optical path according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of a BOSA package according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of a multi-channel BOSA optical path provided by an embodiment of the present invention;

FIG. 7 is a schematic structural diagram of a BOSA according to an embodiment of the present invention;

fig. 8 is a perspective view of a single-fiber bidirectional optical module according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

One of the core elements of fiber optic communications is the conversion of optical to electrical signals. The optical fiber communication uses the optical signal carrying information to transmit in the optical fiber, and the information transmission with low cost and low loss can be realized by using the passive transmission characteristic of the light in the optical fiber. The information processing devices such as computers use electrical signals, which require the interconversion between electrical signals and optical signals during the signal transmission process. The optical module realizes the photoelectric conversion function in the technical field of optical fiber communication, and the interconversion of optical signals and electric signals is the core function of the optical module. In the architecture of the existing optical network, in order to save optical fiber resources, photoelectric devices all adopt a single-fiber bidirectional structure, that is, a transmitting component and a receiving component are packaged in the same device, that is, a single-fiber bidirectional device, such as a single-fiber bidirectional optical module.

The single-fiber bidirectional optical module realizes bidirectional information transmission in one optical fiber by using a Wavelength Division Multiplexing (WDM), and is increasingly used in a PON system because of saving optical fiber resources. The BOSA is a core component for integrating light emission and reception in a single-fiber bidirectional optical module.

Fig. 1 is a schematic diagram of an internal structure of a BOSA, which includes an optical transmitter module 1, an optical receiver module 2, a partial wave plate 3, and an optical fiber ferrule 4. The light emitted by the light emitting component 1 can directly transmit through the partial wave plate 3 and exit from the optical fiber ferrule 4; the light incident into the fiber stub 4 is reflected to the light receiving module 2 after passing through the wave plate 3. The partial wave plate 3 is usually implemented by a glass slide based on a coating technology, and the main function of the partial wave plate is to realize the separation of the emitted light of the light emitting module 1 and the received light of the light receiving module 2. It should be noted that the partial wave plate 3 may be a single glass slide, or may be a combination of a plurality of glass slides, as shown in fig. 2, which is different from the BOSA structure shown in fig. 1 only in that the partial wave plate 3' is implemented by a combination of three glass slides. The light emitting module 1 and the light receiving module 2 are generally implemented by a Transistor Outline package (TO-Can), as shown in a diagram a of fig. 3, the package is shaped like a cylinder and includes a housing base 1, a housing cap 2 and a PIN 3, and the housing base 1 and the housing cap 2 may be integrated by gluing or welding. In the diagram a, a PIN connection mode is adopted, a part of the reserved length of the PIN is used for welding firmly, the redundant part is cut off, the reserved part can influence the impedance continuity of signals, and the high-frequency characteristic of a device is limited, so that the structure is usually only suitable for low-speed optical modules below 50GE and is rarely used in high-speed optical modules above 50GE, especially above 100 GE. In addition, the diagram b shows a packaging form of a light emitting module and a light receiving module which can be applied to a high-speed optical module, the packaging form adopts a through-wall ceramic structure, the through-wall ceramic means that a ceramic sheet 2 is attached to a wall 1, and a ceramic ferrule 3 penetrates through the ceramic sheet to be connected with the ceramic sheet, so that impedance can be effectively controlled, and light energy is coupled into a receiving device to the maximum extent, therefore, high-frequency characteristics are better, but the thickness, the impedance coefficient, the air tightness and the like of the ceramic ferrule 3 have strict requirements, so that the manufacturing technology is complex, the packaging cost of the through-wall ceramic is higher, and the requirement of low-cost packaging cannot be met.

In summary, how to implement the BOSA in the optical module in the high-speed optical transmission scenario with low cost is an urgent problem to be solved. Based on this, the invention provides a scheme for realizing low-cost and high-speed application of BOSA by using a Chip On Board (COB) technology. COB packaging is to mount optical chip directly on circuit board and then to make optical path, that is to adhere bare chip on interconnection substrate by conductive or non-conductive adhesive, then to make wire bonding to realize its electrical connection. The optical module circuit manufactured by the COB packaging process has higher integration level, smaller volume, lower cost and shorter manufacturing and processing period.

Fig. 4 is a schematic diagram of an optical path of a single-channel BOSA according to an embodiment of the present invention, in which a is an overall top view of the single-channel BOSA, and b is a front view of the single-channel BOSA. As shown in fig. 4, the BOSA includes an optical transmitting unit 1, an optical Fiber Array (FA) 2, a Planar light waveguide (PLC) chip 3, a splitting and combining device 4, a reflecting surface 5, and an optical receiving unit 6. The light transmitting unit 1 and the FA2 are connected by an optical fiber, the wave splitting and combining device 4 and the reflecting surface 5 are both located on the PLC chip 3, the FA2 and the PLC chip 3 can be coupled by gluing or welding, and the light receiving unit 6 is located right below the reflecting surface 5 and is used for receiving incident light reflected from the reflecting surface 5. Specifically, the light λ emitted from the light transmission unit 1₁The light enters the PLC chip 3 through a port 1 on FA2, and then is emitted from a port 2 through a wave-splitting and combining device 4 in the PLC chip 3; light λ incident from port 2₂FA2 enters the PLC chip 3 and reaches the reflecting surface 5 after passing through the wave splitting and combining device 4 in the PLC chip 3, the reflecting surface 5 is an inclined surface with an included angle alpha with the horizontal line, and the incident light lambda can be converted into the incident light lambda₂To be reflected into the underlying light receiving unit 6. The light receiving unit 6 can receive the light λ reflected from the reflecting surface 5 by direct coupling₂Then the incident optical signal lambda is₂Converted into an electric signal, and amplified in an amplifier.

As an example, the reflecting surface 5 has an angle α with the horizontal lineAt an angle of 45 degrees, so that the incident light λ reaching the reflecting surface 5₂After reflection, the light will be vertically incident on the light receiving unit 6 below, and at this time, the return loss performance of the device will be deteriorated due to the excessive intensity of the reflected light at the plane 7, so that the reflection of the incident light can be reduced at the plane 7 by plating an antireflection film. The Return Loss is also called Return Loss (RL), and is a parameter indicating signal reflection capability, specifically, a measure of Return along an input path in input optical power of a PLC chip, and is represented by a formula RL-10 lgp_r/p_iIs represented by the formula, wherein p_iIs the incident light power, p_rTo receive the returned optical power from the same input. In this embodiment, the smaller the return loss value, the better, which reduces the effect and damage of the reflected light on the device and system, for example, the return loss is less than-26 dB in this embodiment.

As another example, the reflecting surface 5 is designed to have an angle α of 42 degrees with the horizontal, so that the deviation from 45 degrees can avoid the incident light λ₂The vertical incidence of (2) reduces the reflected light power at the plane 7, thereby reducing the return loss of the optical path. At this time, the position of the plane 7 is not required to be plated with an antireflection film or only an antireflection film with lower light transmission requirement. It should be understood that the included angle α between the reflecting surface 5 and the horizontal line in this embodiment is a range, and may generally be any value between 30 ° and 60 °, as long as the return loss requirement can be satisfied on the premise of meeting the design of the optical path.

It should be noted that, by adopting the above-mentioned angle design of the reflecting surface 5, only by reasonably controlling the distance (for example, 10 μm) between the PLC chip 3 and the light receiving unit 6, the incident light signal reflected by the reflecting surface 5 can be directly coupled without adopting a complicated spatial optical structure, so that the optical path design can be simplified.

In the embodiment of the present invention, the transmitted optical signal may be laser with a wavelength of 1310nm, and the received optical signal may be laser with a wavelength of 1270 nm. After the optical transmission unit 1 generates the transmission optical signal, the port 1 of the FA2 may be incident on the PLC chip 3, exit from the port 2 via the multiplexing/demultiplexing device 4, and the reception optical signal may be incident via the port 2, reach the reflection surface 5 via the multiplexing/demultiplexing device 4, be reflected by the light on the reflection surface 5, and be coupled to the optical reception unit 6.

In a specific embodiment, the optical transmitting unit 1 may be a Laser Diode (LD); the wavelength division and combination device 4 can be one of an arrayed Waveguide Grating (AWG for short), a Mach-Zehnder modulator (MZM for short) and a micro-ring resonator; the light receiving unit 6 may include a Photodetector (PD) 8 and an amplifier 9, and an output terminal of the PD8 is connected to an input terminal of the amplifier 9. The LD can be provided with a laser driver matched with the LD and is connected with the LD through a driving circuit; the Amplifier 9 is preferably a Trans-Impedance Amplifier (TIA).

The optical transmitting unit 1, the driving circuit and the optical receiving unit 6 may be disposed on a carrier, which may be a Printed Circuit Board (PCB), a flexible board, a ceramic substrate or an organic board. Preferably, the optical transmitting unit 1, the driving circuit and the optical receiving unit 6 are all disposed on a PCB, a flexible circuit board is disposed on the PCB, and the driving circuit is connected to the LD through the flexible circuit board.

As an example, the optical transmitting unit 1 may be implemented by a package of a TO-CAN or COB; the light receiving unit 6 may be implemented by a COB packaging method. Fig. 5 is a schematic diagram of COB package of the light-receiving unit 6, and as shown in the figure, the light-receiving unit 6 includes a PD61 and an amplifier 62, and both the PD61 and the amplifier 62 are disposed on a PCB and connected by wire bonding. When the incident light is perpendicular to the PCB board or is incident on the PD61 at an angle deviating from the perpendicular, the surface of the PD61 is a photosensitive surface, receives the incident light signal and converts it into an electrical signal, which is then input to the amplifier 62 for power amplification.

In order to save optical fiber resources and reduce cost while realizing high-speed data transmission, the invention also provides a multi-channel BOSA scheme. Fig. 6 is a schematic diagram of an optical path of a multi-channel BOSA according to an embodiment of the present invention, in which a is a general top view of the multi-channel BOSA, and b is a front view of the multi-channel BOSA. As shown in FIG. 6, the multi-channel BOSA includes lightTransmitting unit 1 ', FA 2', PLC chip 3 ', multiplexing/demultiplexing device 4', reflecting surface 5 ', and light receiving unit 6'. The connection mode, relative position and optical path design of the components in this embodiment are the same as those shown in fig. 4, except that: the BOSA provided in this embodiment includes n optical channels (n may be an integer greater than or equal to 2). Correspondingly, on the transmitting side, the optical transmitting unit 1 ' includes n optical transmitting devices, each optical transmitting device includes an optical transmitter, an optical fiber tip and an output optical fiber, one end of the output optical fiber is directly fixed on the optical transmitter through the optical fiber tip, and the other end of the output optical fiber is connected to the port 1 ' on the FA2 '; the number of optical channels in FA 2' is adjusted to 2n, where n channels are used for the light λ emitted from the optical transmission unit 1₁The light is incident to the PLC chip 3 ' through a port 1 ' on the FA2 ', and the rest n channels are used for the emergent light lambda₁The light beam passes through a wave splitting and combining device 4 ' above the PLC chip 3 ' and then is emitted from a port 2 ', and is also used for incident light lambda₂From port 2 'into PLC chip 3'. The PLC chip comprises n optical channels and is used for realizing the parallel transmission of n paths of optical signals. On the receiving side, the light receiving unit 6 'includes a PD 8' and an amplifier 9 ', where the PD 8' can simultaneously receive multiple optical signals, convert the signals into electrical signals through its internal PD tube, and then input the signals into the amplifier for power amplification.

In a specific embodiment, the light emitter may be an LD, and the LD may have a laser driver matching with the LD, and is connected to the LD through a driving circuit; the multiplexing/demultiplexing device 4' may be a single device or a combination of a plurality of multiplexing/demultiplexing devices. The PD 8' may be embodied as a multi-channel PD array comprising a plurality of optical ports for receiving a plurality of incident light beams λ reflected by the reflecting surface 5₂(ii) a The amplifier 9' is preferably TIA, because TIA itself has Automatic Gain Control (AGC) function, and can use large Gain amplification factor for small amplitude electrical signal after small power optical signal conversion, and small Gain amplification factor for large amplitude electrical signal after large power optical signal conversion, so that the amplitude fluctuation of the electrical signal output by TIA is stable.

Preferably, the light transmitting unit 1 ', the driving circuit and the light receiving unit 6' are all disposed on a PCB, a flexible circuit board is disposed on the PCB, and the driving circuit is connected to the LD through the flexible circuit board.

It should be noted that, because the BOSA provided in this embodiment includes a plurality of optical channels, an optical interface of the single-fiber bidirectional optical module including the BOSA is also adjusted to be a Multi-channel optical interface, for example, a Multi-core optical interface (hereinafter referred to as MPO) is adopted. In addition, the multi-channel single-fiber bidirectional optical module can be packaged in the Form of a Double four-channel Small Form Factor plug-Pluggable optical module (QSFP-DD) or an eight-system Small Form Factor plug-Pluggable optical module (OSFP).

The multi-channel BOSA provided by the embodiment can realize parallel transmission of multi-channel data of the optical module through a COB packaging mode, so that the transmission rate and unit transmission capacity of the optical module are improved, the application in a high-speed communication network of 100GE and above is realized, the size of the BOSA can be reduced, the optical module comprising the BOSA is more miniaturized, and the cost is reduced, so that the current market needs are met. For other technical details, embodiments and technical effects of the multi-channel BOSA, reference may be made to the related content of the single-channel BOSA, which is not described in detail in this embodiment.

Fig. 7 is a schematic structural diagram of a BOSA according to an embodiment of the present invention. The BOSA provided by the embodiment of the invention comprises an optical transmitting unit 1, an FA2, a PLC chip 3, a wave-splitting and combining device 4, a reflecting surface 5 and an optical receiving unit 6. Wherein, one end of the light transmitting unit 1 is connected with the light source driver 10 through the driving circuit, the other end is connected with the FA2 through the optical fiber, the light receiving unit 6 is located right below the PLC chip 3 and comprises a light detector 8 and an amplifier 9, and the light detector 8 is used for receiving the incident light reflected from the reflecting surface 5. In addition, the BOSA also comprises a coating plane 7 for reducing the return loss of incident light signals, and the splitting and combining device 4 can realize the transmission of incident light and received light along different paths.

As an example, the optical transmitting unit 1, the driving circuit, the light source driver 10, and the optical receiving unit 6 may be disposed on a carrier board, which may be a PCB, a flexible board, a ceramic substrate, or an organic board. Preferably, the optical transmitting unit 1, the driving circuit and the optical receiving unit 6 are all disposed on a PCB, a flexible circuit board is disposed on the PCB, and the driving circuit is connected to the LD through the flexible circuit board.

In addition, when the BOSA provided by the present embodiment implements the parallel transmission of multi-channel signals, the optical transmitting unit 1 includes multiple optical transmitting devices, each of which includes an optical transmitter (e.g., a laser), an optical fiber stub, and an output optical fiber, one end of the output optical fiber is directly fixed to the optical transmitter through the optical fiber stub, and the other end of the output optical fiber is connected to the port 1 of the FA 2. Correspondingly, the FA2 is adjusted from the original two channels to include 2n (n is an integer greater than 1) channels; meanwhile, the number of channels in the PLC chip is designed to be n times of the original number. On the receiving side, the optical detector 8 in the optical receiving unit 6 may be a PD array, which may be a combination of multiple PDs, including multiple optical ports, where each optical port receives an optical signal of one channel. The output end of the PD array is connected with the input end of the amplifier. In operation, the PD array receives multiple paths of incident light signals reflected from the reflective surface 5, and converts the incident light signals into electrical signals through the PD tubes therein, and the electrical signals are input to the amplifier 9 for power amplification and then enter the signal processing unit (not shown) for processing. It will be appreciated that the amplifier 9 may be a multi-channel TIA amplifier (e.g. a four-channel TIA amplifier) and that two or more TIA amplifiers may be connected to the output of the PD array as necessary to achieve simultaneous power amplification of the multi-channel electrical signal.

Fig. 8 is a three-dimensional structure diagram of an optical module according to this embodiment. Fig. 8 is a perspective view illustrating a structure of an optical module including the BOSA shown in fig. 7, and as shown in fig. 8, the optical module includes: a base 81, a carrier 82, a driver 83, an optical assembly 84, and a signal processing unit 85. Wherein a driver 83, an optical component 84 and a signal processing unit 85 are arranged on said carrier plate 82. The optical module 84 uses the BOSA shown in fig. 7, and specifically includes an optical transmission unit 841, an FA842, a PLC chip 843, a multiplexer/demultiplexer 844 (not shown), and a reflection surface 845. Further, there is also a light receiving unit including a photodetector PD and an amplifier below the PLC chip 843, and only the amplifier 87 is shown since the PD is not shown in the figure due to the limitation of the space.

As one example, the optical transmission unit 841 includes a laser for generating incident light. The signal processing unit 85 may be a microprocessor (DSP for short), a Clock Recovery module (CDR for short), a Limiting Amplifier (LA for short), or other signal processing chips.

In addition, the critical chips in this embodiment are all placed on a carrier 82, which may be a PCB, a flexible board, a ceramic substrate, or an organic board. Preferably, the chips are all arranged on a PCB, and a flexible circuit board is arranged on the PCB. Flexible Printed Circuit (FPC), also known as Flexible Circuit board or Flexible Circuit board, is a highly reliable and Flexible Printed Circuit made of mylar or polyimide as a substrate, and a large number of precision components are embedded in a narrow and limited space by embedding a Circuit design on a Flexible thin plastic sheet, thereby forming a Flexible Circuit. The circuit can be bent at will, is folded, has light weight, small volume, good heat dissipation and convenient installation, and breaks through the traditional interconnection technology.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the present invention. The terms "first," "then," "last," and the like in the description and claims of the present invention and in the above-described drawings are not used to describe a particular order or sequence. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments described herein are capable of operation in other sequences than described or illustrated herein. Furthermore, the terms "comprises" or "comprising," and any variations thereof, are intended to cover non-exclusive items, for example, items or devices that comprise a list of elements are not necessarily limited to those elements explicitly listed, but may include other elements not explicitly listed that are inherent to such items or devices. As an example, the perspective view of the optical module shown in fig. 8 in the embodiment of the present invention includes, in addition to the base 81, the carrier plate 82, the driver 83, the optical component 84, and the signal processing unit 85 specifically listed in the embodiment, other components which are not clearly flowed but are inherent to the optical module, such as a driving circuit, a gold finger, and the like.

While the present application has been described in connection with various embodiments, other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed application, from a review of the drawings, the disclosure, and the appended claims. In the claims, a single hardware or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

Claims

1. A single-fiber bidirectional optical component is characterized by comprising an optical transmitting unit, an optical receiving unit and a planar optical waveguide chip;

the optical transmitting unit is used for transmitting an emergent optical signal with a first wavelength to the planar optical waveguide chip;

the light receiving unit is positioned below the planar optical waveguide chip and used for receiving an incident light signal with a second wavelength;

the planar optical waveguide chip comprises a wave splitting and combining device, a reflecting surface, a first port and a second port, wherein the wave splitting and combining device is used for sending the emergent optical signals received by the first port out through the second port and sending the incident optical signals received by the second port to the optical receiving unit through the reflecting surface; the reflecting surface is arranged between the wave splitting and combining device and the light receiving unit and used for reflecting the incident light signals passing through the wave splitting and combining device to the light receiving unit.

2. The single fiber bi-directional optical assembly of claim 1,

the planar optical waveguide chip is provided with n optical channels (n is more than or equal to 1) for realizing the transmission of n paths of optical signals.

3. The single-fiber bidirectional optical subassembly of any one of claims 1 or 2, wherein: the angle range of a first included angle between the reflecting surface and the horizontal line is 30-60 degrees.

4. The single-fiber bidirectional optical assembly according to any one of claims 1 to 3, wherein the optical receiving unit includes an optical detector and a transimpedance amplifier, both of which are disposed attached to a Printed Circuit Board (PCB);

the optical detector is used for receiving the incident optical signal and converting the incident optical signal into an incident electric signal;

the transimpedance amplifier is used for amplifying and outputting the incident electric signal.

5. The bi-directional optical subassembly of any of claims 1-4, wherein the first angle is 42 degrees, such that the incident optical signal is incident on the photosensitive surface of the optical detector approximately perpendicular to the PCB.

6. The bi-directional optical subassembly of any of claims 1-4, wherein an anti-reflection coating is coated on a plane below the reflective surface, and the anti-reflection coating is used to reduce the return loss of the incident optical signal when the incident optical signal is incident perpendicular to the PCB.

7. The single-fiber bidirectional optical component according to any one of claims 1 to 6, wherein the light receiving unit is located 5 to 15 μm below the planar optical waveguide chip.

8. The bi-directional optical subassembly of any of claims 1-7, wherein the demultiplexing device is an arrayed waveguide grating.

9. The single-fiber bidirectional optical module according to any one of claims 1 to 8, wherein the demultiplexing device is a mach-zehnder modulator.

10. The bi-directional optical subassembly of any of claims 1-9, further comprising an optical fiber array comprising 2n (n ≧ 1) fiber channels.

11. The bi-directional optical subassembly of any of claims 1-10, wherein the optical transmitter unit comprises n (n ≧ 1) lasers configured to transmit n of the outgoing optical signals having the first wavelength simultaneously.

12. The bi-directional optical subassembly of any of claims 1-11, wherein the optical fiber array is coupled to the planar lightwave circuit chip by gluing or soldering.

13. A bidirectional optical single-fiber module comprising a light source driver, the bidirectional optical single-fiber module according to any of claims 1 to 12, and a signal processor,

the light source driver is used for driving the single-fiber bidirectional optical component to generate an emergent light signal with a first wavelength;

the single-fiber bidirectional optical component is used for generating and transmitting the emergent light signal, receiving an incident light signal with a second wavelength at the same time, and sending the incident light signal to the signal processor;

and the signal processor is used for processing the incident electric signal converted from the incident optical signal.

14. The bi-directional optical subassembly of claim 13, wherein the bi-directional optical subassembly, the light source driver, and the signal processing unit are disposed on a Printed Circuit Board (PCB).

15. The bidirectional optical transceiver of claim 13 or 14,

the single-fiber bidirectional optical component comprises an optical transmitting unit, an optical receiving unit and a planar optical waveguide chip, wherein the optical transmitting unit is connected with the planar optical waveguide through an optical fiber.

16. The bidirectional optical transceiver of any of claims 13 to 15, wherein the light receiving unit is located 5 to 15 μm below the planar optical waveguide chip.

17. The bi-directional optical module according to any one of claims 13 to 16, wherein the planar optical waveguide chip is provided with a reflective surface for reflecting the received incident optical signal to the optical receiving unit.

18. The bi-directional optical transceiver of any one of claims 13-17, wherein the light source driver is connected to the light transmitting unit via a driving circuit, and the driving circuit is located on the PCB.

19. The bidirectional optical transceiver of any of claims 13-18,

the optical sending unit comprises a plurality of lasers and is used for simultaneously generating a plurality of paths of emergent optical signals;

the light receiving unit comprises a light detector array and a transimpedance amplifier, the light detector array is provided with a plurality of light ports and is used for receiving a plurality of paths of incident light signals simultaneously and converting the plurality of paths of incident light signals into incident electric signals, and the transimpedance amplifier is used for amplifying the plurality of paths of incident electric signals.

20. The bi-directional optical fiber module of any one of claims 13-19, wherein an input terminal of the signal processing unit is connected to an output terminal of the transimpedance amplifier, and receives and processes the incident electrical signal output from the transimpedance amplifier.