WO2019173998A1

WO2019173998A1 - Optical receiving assembly, combined transceiver assembly, combined optical module, olt and pon system

Info

Publication number: WO2019173998A1
Application number: PCT/CN2018/079137
Authority: WO
Inventors: 陈聪; 董英华; 李书; 杨素林
Original assignee: 华为技术有限公司
Priority date: 2018-03-15
Filing date: 2018-03-15
Publication date: 2019-09-19
Also published as: CN111869136B; CN111869136A

Abstract

Embodiments of the present application provide an optical receiving assembly, a combined transceiver assembly, a combined optical module, an OLT and a PON system, relating to the field of optical communication technology. The optical receiving assembly comprises a first housing, the first housing being provided with a light entering port and an optical fiber access port, a first demultiplexer being provided at the light entering port, a first optical waveguide being connected between the first demultiplexer and the optical fiber access port, the first housing being provided with a second demultiplexer, a first optical receiver and a second optical receiver therein, a downlink optical signal entering from the light entering port, being transmitted by means of the first demultiplexer and being transmitted by the first optical waveguide to the optical fiber access port, an uplink optical signal entering from the optical fiber access port, sequentially being transmitted by means of the first optical waveguide, reflected by the first demultiplexer, and demultiplexed by the second demultiplexer, and then inputted into the first optical receiver and the second optical receiver.

Description

Optical receiving, combined transceiver components, combined optical modules, OLT and PON systems

Technical field

The present application relates to the field of optical communication technologies, and in particular, to a light receiving component, a combined transceiver component, a combined optical module, an optical line terminal, and a passive optical network system.

Background technique

Passive Optical Network (Passive Optical Network) such as EPON (Ethernet Passive Optical Network) (EPON) and Gigabit Passive Optical Network (GPON) The PON) system has begun large-scale deployment and achieved fiber-to-the-home. The downlink rate of GPON/EPON is 2.5 Gbps or 1.25 Gbps, and the behavior is 1.25 Gbps. However, with the development of services such as high-definition video and network cloud disk, the demand for higher bandwidth is also increasing. XG(S)-PON, That is, the deployment of a 10 Gbps downlink rate PON network has been put on the agenda.

XG(S)-PON is a tree-like optical network structure like GPON/EPON. Figure 1 shows the general structure of a PON system. Generally speaking, a passive optical network system includes an optical line terminal (OLT) at the central office, and a passive optical splitter (POS) for branching/coupling. And an optical network unit (ONU). All the optical links from the OLT to the ONU are called optical delivery networks (ODNs). The direction from the OLT to the ONU is called the downlink direction. The 1680nm center wavelength is used in the EPON network, and the 1577nm center wavelength is used in the XG(S)-PON; the uplink direction is from the ONU to the OLT direction, and the 1310nm center wavelength is used in the G/EPON network. In the XG(S)-PON A center wavelength of 1270 nm is used.

Since operators have deployed a large number of G/EPON optical networks, and some users use G/EPON to meet the demand, not all users need higher speeds. In order to save costs and take care of different needs, operators hope XG (S ) - PON or next-generation PON (such as 25GPON) can be compatible with existing G/EPON, sharing ODN network, but because G/EPON and XG(S)-PON use different upstream and downstream wavelengths, The OLT side needs to add optical transmitters and receivers of different wavelengths, so that G/EPON and XG(S)-PON can work simultaneously. This integrates multiple PON standard transmitters and receivers into one packaged optical component. The optical device is called a combined optical component (Combo PON).

Combo PON optical components are the research hotspots in the industry. Because the functions of G/EPON and XG(S)-PON need to be integrated into one optical module, the optoelectronic devices are multiplied, facing miniaturization, low cost, high performance. Low power and other issues.

Traditional Transistor Outline (TO) packaged G/EPON Bi-directional Optical Sub Assembly (BOSA), mainly composed of Laser Diode (LD) TO, Photodiode (PD) TO The filter, the square tube body and the fiber access port (receptacle) are composed of components, and the receptacle is a component containing the ceramic ferrule and the optical fiber, because the transmitting end of the LD TO is relatively close to the receiving end face of the receptacle, about 4-6 mm. Therefore, non-parallel optical coupling is generally used. The principle of non-parallel optical coupling is to collimate and converge the light emitted by the LD through a coupling lens, and directly couple with the end face of the optical fiber. The size is small, the coupling technology is mature, and the cost is low.

The Combo optical component has two optical devices and two optical devices. The package schematic is shown in FIG. 2. The housing 01 is packaged with two transmitters 02 and two receivers 03. The size of the device increases due to the increase of optical devices. The coupling distance between the transmitter 02 and the fiber end face 04 is greatly increased, and the distance H from the farthest 10G LD transmitting end to the fiber end face is about 16-20 mm, which is much larger than the conventional BOSA device 4-6 mm coupling distance. Still using non-parallel optical coupling, the coupling efficiency will be greatly reduced, from 60% to 6%, and the coupling loss is too large.

If a parallel optical coupling system is used, the light emitted by the LD needs to be collimated into a parallel beam by a parallel optical coupling lens, and the transmission distance is still parallel, and then a converging lens is coupled with the end face of the fiber. In the Combo PON optical component shown in FIG. 2, since there are two transmitting optical paths and two receiving optical paths, and the two transmitting optical paths share the same converging lens and receiving optical fiber, the converging spot is concentrated at the same end by the optical fiber receiving end. Receiving means that the parallel beams of multiple emission paths must be parallel to each other, so the two-way emission TO must be actively coupled to ensure coupling efficiency. Through simulation experiments, the positional offset and angular offset have an effect on the coupling efficiency, and the angular offset has a great influence on the coupling efficiency. Therefore, the combo optical component with parallel optical coupling must give priority to the optical path angle. Source coupling, then active adjustment of the position offset, requires six dimensions of adjustment. The three-dimensional adjustment from the six-dimensional adjustment to the angle-only adjustment can only be achieved if the displacement accuracy is sufficient. As a result, parallel optical coupling systems are costly when applied to combo PON optical components.

Summary of the invention

The embodiments of the present application provide a light receiving component, an optical transmitting component, a combined transceiver component, a combined optical module, an optical line terminal, and a passive optical network system, which solve the problem of high cost of the existing Combo PON optical component.

To achieve the above objective, the embodiment of the present application adopts the following technical solutions:

In a first aspect, the present application provides a light receiving component, including a first housing, the first housing is provided with an optical entrance and an optical fiber inlet, and the first optical splitter is disposed at the optical entrance, and the first splitter A first optical waveguide is connected between the optical fiber access port and the second optical splitter, the first optical receiver and the second optical receiver are disposed in the first housing, and the downstream optical signal enters through the optical entrance and passes through the first After being transmitted, the splitter is transmitted from the first optical waveguide to the optical fiber access port, and the upstream optical signal enters through the optical fiber access port, and is sequentially transmitted through the first optical waveguide, the first splitter is reflected, and the second splitter is split and respectively A first light receiver and a second light receiver are input.

In the light receiving component provided by the embodiment of the present application, since the optical waveguide is used as the optical path in the first casing, the descending optical signal is sequentially transmitted through the first splitter, and the first optical waveguide is transmitted to enter the optical fiber inlet, due to the optical waveguide. The mode field and the mode field of the fiber are matched, so the coupling efficiency is high. The first optical waveguide connecting the fiber access port and the first splitter is equivalent to shortening the coupling distance between the fiber inlet and the first splitter. Therefore, the coupling of the transmitting end can use the conventional non-parallel optical coupling, and the coupling process is mature and convenient, and the cost is low.

In a possible implementation manner, the second splitter is a planar lightwave loop type splitter, and the planar lightwave loop type splitter comprises a second optical waveguide and a third optical waveguide, and the second optical waveguide is connected to the first optical receiver. The third optical waveguide is connected to the second optical receiver.

In a possible implementation, a substrate is disposed in the first housing, and the first optical waveguide, the second optical waveguide, and the third optical waveguide are integrated optical waveguides formed on the substrate. Thereby, the integrated chip can be made smaller in size and the package structure is more compact.

In a possible implementation, the first optical waveguide, the second optical waveguide, and the third optical waveguide are optical fibers.

In a possible implementation manner, the first light receiver and the second light receiver are waveguide type photodetectors, the first light receiver is formed on the second optical waveguide by a semiconductor patterning process, and the second light receiver is patterned by the semiconductor The process is formed on a third optical waveguide. This further reduces costs.

In a possible implementation, the waveguide type photodetector may employ a silicon germanium waveguide type PD.

In a possible implementation, the first light receiver and the second light receiver may be avalanche photodiodes to improve the sensitivity of the detection.

In a possible implementation manner, the second splitter is a thin film filter type splitter, and the second splitter and the first splitter are connected by a fourth optical waveguide, and the first optical receiver is located at the second splitter On the transmitted light path of the wave device, the second light receiver is located on the reflected light path of the second splitter, and the second light receiver and the second splitter are connected by the fifth optical waveguide.

In a possible implementation, a substrate is disposed in the first housing, and the first optical waveguide, the fourth optical waveguide, and the fifth optical waveguide are integrated optical waveguides formed on the substrate.

In a possible implementation, the first optical waveguide, the second optical waveguide, the third optical waveguide, the fourth optical waveguide, and the fifth optical waveguide are a silicon dioxide waveguide, a silicon waveguide, an InP waveguide, or a silicon nitride waveguide.

In a possible implementation, the downlink optical signal includes an optical signal of a wavelength of 1490 nm and an optical signal of a wavelength of 1577 nm; the upstream optical signal includes an optical signal of a wavelength of 1310 nm and an optical signal of a wavelength of 1270 nm.

In a second aspect, the present application provides an optical transmitting component capable of transmitting a downlink optical signal to an optical entrance of a light receiving component, and the optical transmitting component adopts a non-parallel optical coupling structure.

Since the optical transmitting component provided by the embodiment of the present application uses a conventional non-parallel optical coupling structure, the coupling process is mature and low in cost.

In a possible implementation manner of the second aspect, the light transmitting component includes a second housing, the second housing is provided with a light exiting opening, and the light emitting opening is opposite to the light receiving opening of the light receiving component, and the first light is disposed in the second housing a transmitter, a second optical transmitter and a combiner, wherein the combiner is located on a transmitting optical path of the first optical transmitter and the second optical transmitter, and the first non-parallel light is disposed between the combiner and the first optical transmitter a coupling lens, a second non-parallel optical coupling lens is disposed between the combiner and the second optical transmitter, and the combiner can transmit the optical signals sent by the first optical transmitter and the second optical transmitter to the optical outlet. . Since only one non-parallel optical coupling lens is disposed on the light path of the first optical transmitter and the second optical transmitter, and a combination structure of the collimating lens and the converging lens is not used, non-parallel optical coupling is adopted, and Multi-dimensional adjustment when parallel optical coupling is performed, thereby reducing the manufacturing cost of the Combo PON.

In a possible implementation manner of the second aspect, the combiner may be a filter-type combiner, and the optical signal sent by the first optical transmitter is transmitted through the filter-type combiner and then emitted by the light-emitting port, and the second optical transmitter is emitted. The emitted optical signal is reflected by the filter-type combiner and then emitted from the light exit port.

In a third aspect, the application provides a combined transceiver component, including:

The light receiving component, the light receiving component is the light receiving component of any one of the above first aspects.

In a fourth aspect, the application provides a combined transceiver component, including:

The optical transmitting component, which is the optical transmitting component in any one of the above second aspects.

In a fifth aspect, the application provides a combined transceiver component, including:

a light receiving component, the light receiving component is the light receiving component of any one of the above first aspects;

In the combined transceiver assembly provided by the embodiment of the present application, since the optical waveguide is used as the optical path in the first housing of the light receiving component, the downlink optical signal sent by the optical transmitting component is sequentially transmitted through the first splitter and transmitted by the first optical waveguide. Enter the fiber access port. Since the mode field of the optical waveguide and the mode field of the optical fiber are matched, the coupling efficiency is high, and the first optical waveguide connecting the optical fiber inlet and the first splitter is equivalent to the optical transmitter in the optical fiber inlet and the optical transmitting component. The coupling distance between the two is shortened. Therefore, the coupling of the optical transmitting component can use a conventional non-parallel optical coupling structure, and the coupling process is mature and low in cost.

In a sixth aspect, the present application provides a combined optical module, including the light receiving component of the first aspect, or the optical transmitting component of the second aspect, or the electronic component and the third aspect, the fourth aspect, and the fifth The combined transceiver component of any one of the aspects, wherein the electronic component is electrically connected to the light receiving component and the light transmitting component of the combined transceiver component, respectively.

In a seventh aspect, the present application provides an optical line terminal, including the combined optical module in the technical solution of the sixth aspect.

In a possible implementation manner of the seventh aspect, the optical line terminal further includes a single board and a chassis for placing the combined optical module.

In an eighth aspect, the application provides an optical network unit, including the combined optical module in the technical solution of the sixth aspect.

In a ninth aspect, the present application provides a passive optical network system, including:

An optical line terminal, wherein the optical line terminal is an optical line terminal in any one of the technical solutions of the seventh aspect;

a light distribution network, the light distribution network is connected to the optical line terminal;

A plurality of optical network units, the plurality of optical network units being connected to the optical distribution network.

In a possible implementation of the ninth aspect, the optical module of the at least one of the plurality of optical network units is a GPON optical module, and the optical module of the at least one of the optical network units is an XGPON optical module; or

The optical module of the at least one of the plurality of optical network units is an EPON optical module, and the optical module of at least a part of the optical network unit is a 10G-EPON optical module; or

The optical module of at least a part of the plurality of optical network units is the combined optical module in the technical solution of the sixth aspect.

It can be understood that, when the optical network unit adopts the non-combined optical module, each of the plurality of optical network units may include at least one of a GPON optical module, an XGPON optical module, a 25G-GPON optical module, and a 50G-GPON optical module. For example, each of the plurality of optical network units may include at least two of an EPON optical module, a 10G-EPON optical module, a 25G-EPON optical module, and a 50G-EPON optical module. When the optical network unit adopts the combined optical module, the combined optical module can simultaneously support any two of GPON, XGPON, 25G GPON, and 50G GPON, or support any two of EPON, 10GEPON, 25G EPON, and 50G EPON.

The combined optical module, the optical line terminal, and the passive optical network system provided by the embodiments of the present application, because the optical receiving component in the combined optical module uses an optical waveguide as the optical path, and the mode field of the optical waveguide and the mode field of the optical fiber Matching, so the coupling efficiency is very high, and the first optical waveguide connecting the fiber access port and the first splitter is equivalent to shortening the coupling distance between the optical fiber inlet and the optical transmitter in the optical transmitting component, and therefore, the optical transmitting component The coupling can use traditional non-parallel optical coupling, and the coupling process is mature and low in cost.

DRAWINGS

1 is a network structure diagram of a passive optical network;

2 is a package structure diagram of a Combo optical component;

3 is a schematic diagram of a package structure when a light receiving component adopts a PLC type splitter according to an embodiment of the present application;

4 is a schematic view showing the arrangement positions of the first optical waveguide and the second optical waveguide in FIG. 3;

FIG. 5 is a schematic diagram of a package structure when a light receiving component of the embodiment of the present invention adopts a waveguide type photodetector;

6 is a schematic diagram of a package structure when a light receiving component of the embodiment of the present application adopts a TFF type splitter;

7 is a schematic diagram of a package structure when a combined transceiver unit adopts a PLC type splitter according to an embodiment of the present application;

FIG. 8 is a schematic diagram of a package structure when a combined transceiver component adopts a TFF type splitter according to an embodiment of the present application.

detailed description

The embodiments of the present application relate to a light receiving component, an optical transmitting component, a combined transceiver component, a combined optical module, and a passive optical network system. The following briefly describes the concepts involved in the foregoing embodiments:

Passive Optical Network (PON): A passive optical network refers to an optical fiber distribution network (ODN) between an OLT and an ONU without any active electronic equipment.

Optical distribution network (ODN): The ODN is a fiber-to-the-home cable network based on PON equipment. Its role is to provide an optical transmission channel between the OLT and the ONU.

Wavelength division multiplexing (WDM): Wavelength division multiplexing is the convergence of two or more optical carrier signals of different wavelengths (carrying various kinds of information) at the transmitting end via a multiplexer (also known as a combiner). a technology that is coupled together and coupled to the same fiber of the optical line; at the receiving end, a demultiplexer (also known as a splitter or demultiplexer) separates optical carriers of various wavelengths, and then Further processing by the optical receiver to recover the original signal. This technique of simultaneously transmitting two or many different wavelength optical signals in the same fiber is called wavelength division multiplexing.

Optical transmission module: referred to as optical module, including Bi-directional Optical Sub-assembly (BOSA) and Electronic Subassembly (ESA). The optical transmission module is electrically connected to the peripheral electronic component (ESA) and then to the optical module housing, thereby forming an optical transmission module.

Bi-directional Optical Sub-assembly (BOSA): mainly includes a Transmitting Optical Sub-assembly (TOSA) and a Receiving Optical Sub-assembly (ROSA).

Transmitting Optical Sub-assembly (TOSA): The role of TOSA is to convert an electrical signal into an optical signal and input it into an optical fiber for transmission.

Receiving Optical Sub-assembly (ROSA): The role of ROSA is to receive the optical signal transmitted from the optical fiber and perform electrical signal conversion.

Optical waveguide: A medium device that guides the propagation of light waves therein, also known as a dielectric optical waveguide. There are two broad categories of optical waveguides: one is an integrated optical waveguide, including planar (thin film) dielectric optical waveguides and strip dielectric optical waveguides, which are usually part of optoelectronic integrated devices (or systems), so called integrated optical waveguides. The other type is a cylindrical optical waveguide, commonly referred to as an optical fiber.

An optical module that can support any two different transmission rates at the same time may be referred to as a Combo optical module. For example, in one example, the combined optical module can simultaneously support any two of GPON, XGPON, 25G GPON, and 50G GPON. Or support any two of EPON, 10GEPON, 25G EPON, and 50G EPON. It can be understood that the above combined optical module can also be referred to as an optical module.

The following describes GPON as an example. The EPON scenario can be considered similarly.

For the wavelength of the optical signal, the optical line terminal in the GPON transmits at a wavelength of 1490 nm and receives at a wavelength of 1310 nm. The optical line terminal in the XGPON transmits at a wavelength of 1577 nm and receives at a wavelength of 1270 nm. Then, in the combined transceiver component, the two sets of wavelength optical signals need to be received and transmitted, and a certain structural design is used to achieve coexistence, which requires a series of WDM modules (synthesizers or splitters). Convergence and separation of light at two wavelengths.

As shown in FIG. 3, the embodiment of the present application provides a light receiving component, including a first housing 1. The first housing 1 is provided with an optical entrance 11 and an optical fiber inlet 12, and the optical inlet 11 is provided with a first a first optical waveguide 31 is connected between the first demultiplexer 2 and the optical fiber inlet 12, and a second demultiplexer 4, a first optical receiver 51 and a first The second optical receiver 52, the downstream optical signal a1 enters through the optical port 11 and is transmitted by the first demultiplexer 2, and then transmitted by the first optical waveguide 31 to the optical fiber access port 12, and the upstream optical signal b1 is accessed by the optical fiber access port 12. And sequentially transmitted through the first optical waveguide 31, reflected by the first demultiplexer 2, and demultiplexed by the second demultiplexer 4, and then input to the first optical receiver 51 and the second optical receiver 52, respectively.

In the light receiving component provided by the embodiment of the present application, since the optical waveguide is used as the optical path in the first casing 1, the downstream optical signal a1 is sequentially transmitted through the first splitter 2, and the first optical waveguide 31 is transmitted to enter the optical fiber inlet. 12, since the mode field of the optical waveguide and the mode field of the optical fiber are matched, the coupling efficiency is high, and the first optical waveguide 31 connecting the optical fiber inlet 12 and the first demultiplexer 2 is equivalent to the optical fiber inlet 12 and the first The coupling distance between the splitter 2 is shortened. As shown in Fig. 7, the coupling distance is shortened from the original D1 to D2. Therefore, the coupling of the transmitting end can use the conventional non-parallel optical coupling, and the coupling process is mature and convenient, and the cost is low.

The second demultiplexer 4 functions to separate the upstream optical signal b1, and the second demultiplexer 4 can be a Planar Lightwave Circuit (PLC) type demultiplexer or a thin film filter (Thin Flim Filter, TFF). The type of splitter or the like is not limited herein. When the second splitter 4 is a planar lightwave loop type combiner, the specific package structure is as shown in FIG. 3, and the planar lightwave loop type splitter includes the second light. The waveguide 41 and the third optical waveguide 42, the second optical waveguide 41 is connected to the first optical receiver 51, and the third optical waveguide 42 is connected to the second optical receiver 52. The upstream optical signal b1 entered by the optical fiber access port 12 is transmitted to the first splitter 2 through the first optical waveguide 31, and is reflected by the first splitter 2 to the second splitter 4, and the optical signal passes through the second The optical waveguide 41 is transmitted to the first optical receiver 51, and the other optical signal is transmitted along the third optical waveguide 42 to the second optical receiver 52. As shown in FIG. 4, the second optical waveguide 41 may extend along the reflected optical path of the first optical waveguide 31 with respect to the first demultiplexer 2.

The optical waveguide includes an integrated optical waveguide and a cylindrical optical waveguide, wherein the integrated optical waveguide includes a planar (thin film) dielectric optical waveguide and a strip dielectric optical waveguide, and the cylindrical optical waveguide is an optical fiber. In the possible implementation of the present application, the first optical waveguide 31, the second optical waveguide 41, and the third optical waveguide 42 may be an integrated optical waveguide or an optical fiber, which is not limited herein.

Specifically, when the optical waveguide adopts the integrated optical waveguide, as shown in FIG. 3, the optical waveguide can be integrated on the substrate 13, that is, the first optical waveguide 31, the second optical waveguide 41, and the third optical waveguide 42 are all patterned by the semiconductor. The process is integrated on the substrate 13. As a result, the integrated chip can be made smaller in size and the package structure is more compact, so that the entire Combo PON optical component can realize SFP+ (Small Form-factor Pluggables) package size.

The first photoreceiver 51 and the second photoreceiver 52 may be an avalanche photodiode (APD), which is a pn junction type photodetecting diode in which avalanche multiplication of carriers is utilized. The effect is to amplify the photoelectric signal to increase the sensitivity of the detection. Because the photosensitive surface of the APD is relatively large, the coupling of the APD and the optical waveguide is relatively easy, and passive coupling can be used, that is, the APD is directly mounted on the optical waveguide after designing the corresponding position. In addition, when the optical waveguide adopts the integrated optical waveguide, the first optical receiver 51 and the second optical receiver 52 may also adopt a waveguide type photodetector. As shown in FIG. 5, the first optical receiver 51 is formed by a semiconductor patterning process. On the second optical waveguide 41, the second optical receiver 52 is formed on the third optical waveguide 42 by a semiconductor patterning process. Thereby, integrating the photodetector directly with the waveguide can further reduce the cost.

For example, a waveguide type photodetector can employ a silicon germanium waveguide type PD to form a germanium layer on a conventional silicon waveguide, thereby obtaining a photodetector having good performance suitable for optical communication. Of course, the waveguide type photodetector can also be made of other materials.

When the second demultiplexer 4 is a TFF type demultiplexer, as shown in FIG. 6, the second demultiplexer 4 and the first demultiplexer 2 are connected by a fourth optical waveguide 32, and the first optical receiver 51 is connected. Located on the transmitted optical path of the second demultiplexer 4, the second optical receiver 52 is located on the reflected optical path of the second demultiplexer 4, and the second optical receiver 52 and the second diplexer 4 are passed through the fifth optical waveguide 33. connection. The upstream optical signal b1 entered by the optical fiber access port 12 is transmitted to the first splitter 2 through the first optical waveguide 31, and is reflected by the first splitter 2 to the second splitter 4, and the optical signal passes through the second The splitter 4 is transmitted and transmitted to the first optical receiver 51, and the other optical signal is reflected by the second splitter 4 and transmitted to the second optical receiver 52 via the fifth optical waveguide 33.

Likewise, the fourth optical waveguide 32 and the fifth optical waveguide 33 may also be integrated optical waveguides formed on the substrate 13. Specifically, the first optical waveguide 31, the second optical waveguide 41, the third optical waveguide 42, the fourth optical waveguide 32, and the fifth optical waveguide 33 may be a silicon dioxide waveguide, a silicon waveguide, an InP waveguide, or a silicon nitride waveguide.

Taking the signal wavelengths of GPON and XGPON as an example, the downstream optical signal a1 includes an optical signal of 1490 nm wavelength and an optical signal of 1577 nm wavelength; the upstream optical signal b1 includes an optical signal of 1310 nm wavelength and an optical signal of 1270 nm wavelength.

As shown in FIG. 7 and FIG. 8 , the embodiment of the present application further provides a combined transceiver component, including:

The light receiving component 100, the light receiving component 100 is the light receiving component in any of the above embodiments;

The optical transmitting component 200 can transmit the downstream optical signal a1 to the light entrance 11 of the light receiving component, and the optical transmitting component adopts a non-parallel optical coupling structure.

In the combined transceiver assembly provided by the embodiment of the present application, since the optical waveguide is used as the optical path in the first housing 1 of the light receiving component, the downstream optical signal a1 emitted by the optical transmitting component is sequentially transmitted through the first splitter 2, and the first After the optical waveguide 31 is transmitted, it enters the fiber access port 12. Since the mode field of the optical waveguide and the mode field of the optical fiber are matched, the coupling efficiency is high, and the first optical waveguide 31 connecting the optical fiber inlet 12 and the first splitter 2 is equivalent to the optical fiber inlet 12 and the optical transmitting component. The coupling distance between the optical transmitters is shortened. Therefore, the coupling of the optical transmitting components can use a conventional non-parallel optical coupling structure, and the coupling process is mature and low in cost.

Specifically, in order to realize the non-parallel optical coupling of the optical transmitting component, the structure of the optical transmitting component may be as shown in FIG. 7 , and includes a second housing 6 , and the second housing 6 is provided with an optical outlet, an optical outlet and a light receiving component. The light entrance 11 is opposite, and the second housing 6 is provided with a first optical transmitter 71, a second optical transmitter 72 and a combiner 8, and the combiner 8 is located at the first optical transmitter 71 and the second optical transmitter. A first non-parallel optical coupling lens 711 is disposed between the combiner 8 and the first optical transmitter 71, and a second non-parallel light is disposed between the combiner 8 and the second optical transmitter 72. The coupling lens 721 and the combiner 8 can multiplex the optical signals transmitted by the first optical transmitter 71 and the second optical transmitter 72 to the light exit port. Since only one non-parallel optical coupling lens is disposed on the light path of the first optical transmitter 71 and the second optical transmitter 72, and a combination of a collimating lens and a converging lens is not used, non-parallel optical coupling is adopted. Multi-dimensional adjustment when parallel optical coupling is not required, thereby reducing the manufacturing cost of the Combo PON.

The multiplexer 8 can be a filter-type multiplexer 8. As shown in FIG. 7, the optical signal emitted by the first optical transmitter 71 is transmitted through the filter-type multiplexer 8 and then emitted from the light-emitting port. The optical signal from the transmitter 72 is reflected by the filter-type combiner 8 and then emitted from the light-emitting port.

Since the transmission rate of the optical signal of 1577 nm wavelength is high, the corresponding optical transmitter is a high-rate laser, and since the high-rate laser has low tolerance to reflected light, the reflected light has a great influence on the laser. Therefore, as shown in FIG. 7 As shown, an isolator 9 can be provided on the light exit side of the optical transmitter for emitting an optical signal of 1577 nanometers wavelength, and the isolator 9 can isolate the reflected light to eliminate the effect of the reflected light on the high rate laser.

The second housing 6 may be a coaxial tube-shell structure, and the first housing 1 may be a box-packing structure. The first housing 1 and the second housing 6 may be separately fabricated and welded, or may be integrally formed. There is no limit here.

The combined transceiver assembly of any of the above embodiments is electrically connected to a peripheral electronic component (ESA) and then loaded into the optical module housing to form a combined optical module.

The optical circuit terminal is formed by connecting the above-mentioned combined optical module to a single board and placing it in the chassis.

Similarly, the above combined optical module can be used in an optical network unit to form an optical network unit that can simultaneously support optical signals of two wavelengths.

When the optical line terminal is applied to a passive optical network system, the passive optical network system includes:

The above optical line terminal;

In the optical transmission module and the passive optical network system provided by the embodiments of the present application, since the optical waveguide is used as the optical path in the first casing 1 of the optical receiving component, and the mode field of the optical waveguide matches the mode field of the optical fiber, Therefore, the coupling efficiency is high, and the first optical waveguide 31 connecting the optical fiber inlet 12 and the first splitter 2 is equivalent to shortening the coupling distance between the optical fiber inlet 12 and the optical transmitter in the optical transmitting component, and therefore, the light The coupling of the transmitting components can use conventional non-parallel optical coupling, and the coupling process is mature and low in cost.

The optical module of the at least one of the plurality of optical network units may be a GPON optical module, and the optical module of at least a part of the optical network unit may be an XGPON optical module; or

The optical module of the at least one of the plurality of optical network units may be an EPON optical module, and the optical module of at least a part of the optical network unit may be a 10G-EPON optical module, or

The optical module of at least a part of the plurality of optical network units is the combined optical module.

In the description of the specification, specific features, structures, materials or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

The above is only a specific embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think of changes or substitutions within the technical scope of the present invention. It should be covered by the scope of the present invention. Therefore, the scope of the invention should be determined by the scope of the appended claims.

Claims

A light receiving component, comprising: a first housing, the first housing is provided with an optical entrance and an optical fiber inlet, and the first optical splitter is provided with a first splitter, the first a first optical waveguide is connected between the splitter and the optical fiber inlet, and a second splitter, a first optical receiver and a second optical receiver are disposed in the first casing, and the downlink optical signal is The light entrance enters and is transmitted by the first splitter to be transmitted by the first optical waveguide to the optical fiber access port, and the upstream optical signal enters through the optical fiber access port, and sequentially passes through the first light. The waveguide transmission, the first demultiplexer reflection, and the second demultiplexer are divided into the first optical receiver and the second optical receiver, respectively.
The light receiving assembly according to claim 1, wherein said second splitter is a planar lightwave loop type splitter, and said planar lightwave loop type splitter comprises a second optical waveguide and a third optical waveguide. The second optical waveguide is coupled to the first optical receiver, and the third optical waveguide is coupled to the second optical receiver.
The light receiving assembly according to claim 2, wherein said first housing is provided with a substrate, and said first optical waveguide, said second optical waveguide, and said third optical waveguide are integrated on said substrate Optical waveguide.
The light receiving assembly according to claim 3, wherein said first light receiver and said second light receiver are waveguide type photodetectors, and said first light receiver is formed by a semiconductor patterning process On the second optical waveguide, the second optical receiver is formed on the third optical waveguide by a semiconductor patterning process.
The light receiving component according to claim 1, wherein said second splitter is a thin film filter type splitter, and said second splitter passes through said first splitter a four optical waveguide connection, the first optical receiver is located on a transmitted optical path of the second diplexer, the second optical receiver is located on a reflected optical path of the second diplexer, and the second The optical receiver and the second splitter are connected by a fifth optical waveguide.
The light receiving assembly according to claim 5, wherein a substrate is provided in the first casing, and the first optical waveguide, the fourth optical waveguide, and the fifth optical waveguide are integrated on the substrate Optical waveguide.
The light receiving assembly according to claim 3 or 6, wherein the first optical waveguide, the second optical waveguide, the third optical waveguide, the fourth optical waveguide, and the fifth optical waveguide are silicon dioxide waveguides, silicon Waveguide, InP waveguide or silicon nitride waveguide.
The light receiving component according to any one of claims 1 to 7, wherein the downstream optical signal comprises a 1490 nm wavelength optical signal and a 1577 nm wavelength optical signal; the upstream optical signal comprises a 1310 nm wavelength The optical signal and the optical signal of 1270 nm wavelength.
A combined transceiver assembly characterized by comprising:

a light receiving component, the light receiving component being the light receiving component of any one of claims 1-8;

And a light transmitting component capable of transmitting a downlink optical signal to an optical entrance of the light receiving component, and the optical transmitting component adopts a non-parallel optical coupling structure.
The combined transceiver assembly according to claim 9, wherein the light transmitting component comprises a second housing, and the second housing is provided with a light exit opening, the light exit opening and the light receiving component Opposite the optical port, the first housing is provided with a first optical transmitter, a second optical transmitter and a combiner, and the combiner is located on the transmitting optical path of the first optical transmitter and the second optical transmitter. a first non-parallel optical coupling lens is disposed between the combiner and the first optical transmitter, and a second non-parallel optical coupling lens is disposed between the combiner and the second optical transmitter And the multiplexer is capable of transmitting the optical signals sent by the first optical transmitter and the second optical transmitter to the light exit port.
The combined transceiver assembly according to claim 10, wherein the combiner is a filter-type combiner, and the optical signal emitted by the first optical transmitter is transmitted through the filter-type combiner The light exiting from the light exiting port is reflected by the filter-type combiner and is emitted from the light exit port.
A combined optical module, comprising the light receiving component of any one of claims 1-8, or the combined transceiver component of any one of claims 9-11.
An optical line terminal comprising the combined optical module of claim 12.
A passive optical network system, comprising:

An optical line terminal, wherein the optical line terminal is the optical line terminal according to claim 13;

a light distribution network, the light distribution network being connected to the optical line terminal;

a plurality of optical network units, wherein the plurality of optical network units are connected to the optical distribution network;

The optical module of the at least one of the plurality of optical network units is a GPON optical module, and the optical module of the at least one of the optical network units is an XGPON optical module; or

The optical module of the at least one of the plurality of optical network units is an EPON optical module, and the optical module of at least a part of the optical network unit is a 10G-EPON optical module; or

The optical module of at least a portion of the plurality of optical network units is the combined optical module of claim 12.