Patent Application
20210149129
This application relates to the field of optical communications technologies, and in particular, to a receiver optical subassembly, a combo transceiver subassembly, a combo optical module, a communications apparatus, and a passive optical network system.
With development of modern societies, explosive growth of information volumes, and especially the advent of the big data era, there are growing requirements on network throughput capabilities. With unique features such as ultra-high bandwidth and low electromagnetic interference, optical transmission has gradually become a mainstream solution for modern communication. In particular, networks newly established currently, for example, an access network represented by fiber to the home, are being deployed on a large scale.
An optical communications network applied to an access network scenario mainly exists in a form of a passive optical network (PON). In an overall situation in which optical networks are fully popularized, deployment of a large quantity of PON networks requires a same huge quantity of communications devices. A related communications device such as an optical line terminal (OLT) mainly includes an optical module, and a board and a subrack that are used to place the optical module. As shown in
Currently, PON networks deployed on a large scale include two types: an Ethernet passive optical network EPON (EPON) and a gigabit passive optical network (GPON). These two types of optical networks support a rate of 2.5 Gbit/s or 1.25 Gbit/s. With an upgrade of network bandwidth, next-generation networks to be deployed are a 10G-EPON and a 10G-GPON (which may also be referred to as an XGPON), and support a rate of 10 Gbit/s. The following uses a GPON as an example for description. An EPON scenario may be similar. In terms of a wavelength of an optical signal, an optical line terminal in a GPON uses 1490 nanometers for transmitting and 1310 nanometers for receiving, and an optical line terminal in an XGPON uses 1577 nanometers for transmitting and 1270 nanometers for receiving. Assuming that a 10G upgrade is performed in a current GPON network, it is unlikely to reconstruct an ODN network, and therefore service expansion needs to be performed in an existing network. The following scenario inevitably exists: On a user side, some users intend to upgrade to the XGPON, and some users do not intend to upgrade. In this case, a case shown in
Embodiments of this application provide a receiver optical subassembly, a transmitter optical subassembly, a combo transceiver subassembly, a combo optical module, a communications apparatus, and a passive optical network system, so that during multiplexing on uplink and downlink wavelengths, construction costs are lower, less equipment room space is occupied, construction and cabling are simple, and management and maintenance are convenient.
To achieve the foregoing objectives, the following technical solutions are used in the embodiments of this application:
According to a first aspect, this application provides a receiver optical subassembly, including an optical receiving housing. A first optical receiver, a second optical receiver, and a first glass are packaged in the optical receiving housing, and the first glass is disposed obliquely relative to optical receiving paths of the first optical receiver and the second optical receiver. The first glass includes a light incident surface and a light emergent surface, and the first optical receiver and the second optical receiver are disposed opposite to the light emergent surface of the first glass. A first light splitting film is disposed on the light emergent surface of the first glass, and the first light splitting film is located on the optical receiving path of the first optical receiver, and can transmit an optical signal of a first wavelength and reflect an optical signal of a second wavelength. A first reflective film is disposed on a part of the light incident surface of the first glass. The optical signal of the first wavelength and the optical signal of the second wavelength are sent into the first glass from the light incident surface, refracted inside the first glass, and then sent to the first light splitting film. The optical signal of the first wavelength is transmitted through the first light splitting film and enters the first optical receiver, and the optical signal of the second wavelength is sequentially reflected by the first light splitting film and the first reflective film and then sent from the light emergent surface, and enters the second optical receiver.
According to the receiver optical subassembly provided in this embodiment of this application, the first glass is used, the first reflective film is disposed on the light incident surface of the first glass, and the first light splitting film is disposed on the light emergent surface. In addition, the first glass is disposed obliquely relative to the optical receiving paths of the first optical receiver and the second optical receiver. Therefore, after the optical signal of the first wavelength and the optical signal of the second wavelength are sent into the first glass along an optical receiving direction, the optical signal of the first wavelength may be transmitted through the first light splitting film and enter the first optical receiver, and the optical signal of the second wavelength is sequentially reflected by the first light splitting film and the first reflective film and then sent from the light emergent surface, and enters the second optical receiver. In this way, an emergent position of the optical signal of the second wavelength may be separated from an emergent position of the optical signal of the first wavelength by a specific distance, to meet a requirement for a mounting spacing between the first optical receiver and the second optical receiver, thereby implementing receiving of optical signals of different wavelengths based on the wavelengths. In addition, because the first optical receiver, the second optical receiver, and the first glass are all packaged in the same optical receiving housing, and the first light splitting film on the first glass performs a function of demultiplexing, a demultiplexing apparatus is internally disposed. Therefore, this reduces construction costs, reduces occupied equipment room space, simplifies construction and cabling, and facilitates management and maintenance.
In a possible implementation, a second reflective film is further disposed on the light emergent surface of the first glass, and the second reflective film is disposed by keeping away from the optical receiving path of the second optical receiver, and is located between the optical receiving path of the first optical receiver and the optical receiving path of the second optical receiver. After the optical signal of the second wavelength is reflected by the first light splitting film, the optical signal is sequentially reflected between the first reflective film and the second reflective film and sent from the light emergent surface, and enters the second optical receiver. In this way, signal receiving can be satisfied when the mounting spacing between the first optical receiver and the second optical receiver is relatively large.
In a possible implementation, an angle of incidence at which the optical signal of the first wavelength and the optical signal of the second wavelength are sent into the first glass is less than or equal to 12°. Therefore, light splitting isolation is ensured.
In a possible implementation, an angle of incidence at which the optical signal of the first wavelength and the optical signal of the second wavelength are sent into the first glass is 8° to 12°. In this way, not only light splitting isolation is ensured, but also a loss of the optical signal of the second wavelength is relatively small.
In a possible implementation, an angle of incidence at which the optical signal of the first wavelength and the optical signal of the second wavelength are sent into the first glass is 8°.
In a possible implementation, a thickness of the first glass is 0.2 to 2 millimeters. Therefore, it is easy to produce the first glass, costs are low, and an overall size can easily meet a packaging size requirement of an SFP+.
In a possible implementation, a thickness of the first glass is 1.6 millimeters.
In a possible implementation, a first collector lens is disposed between the light emergent surface of the first glass and the first optical receiver, and the first collector lens is disposed on the optical receiving path of the first optical receiver; and a second collector lens is disposed between the light emergent surface of the first glass and the second optical receiver, and the second collector lens is disposed on the optical receiving path of the second optical receiver. Therefore, receiving efficiency of the first optical receiver and the second optical receiver can be improved, and an optical loss can be reduced.
In a possible implementation, an antireflective film is disposed on the light emergent surface of the first glass.
In a possible implementation, the optical receiving housing is a transistor-outline can, the transistor-outline can includes a header and a cap, both the first optical receiver and the second optical receiver are disposed on the header, and the first glass forms a transparent window of the cap. Therefore, this is compatible with an existing TO packaging process, to avoid producing a special complex housing, thereby reducing producing costs.
In a possible implementation, the optical receiving housing is a packaging box, a transparent window is formed on the packaging box, and the first optical receiver, the second optical receiver, and the first glass are all disposed in the packaging box; and the light incident surface of the first glass is opposite to the transparent window of the packaging box. Therefore, a tilt angle and a position of the first glass may be finely adjusted in an active coupling manner, so that the first glass is disposed at a more precise position, and receiving efficiency of the receiver optical subassembly is higher.
According to a second aspect, this application provides a transmitter optical subassembly. The transmitter optical subassembly includes an optical transmitting housing, and a first optical transmitter, a second optical transmitter, and a second glass that are packaged in the optical transmitting housing. The second glass is disposed obliquely relative to optical transmitting paths of the first optical transmitter and the second optical transmitter, the second glass includes a light incident surface and a light emergent surface, and the light incident surface of the second glass is disposed opposite to the first optical transmitter and the second optical transmitter. A second light splitting film is disposed on the light incident surface of the second glass, a third reflective film is disposed on a part of the light emergent surface of the second glass, and the second light splitting film is located on the transmitting path of the first optical transmitter and located on a reflecting path of the third reflective film. The second light splitting film can transmit an optical signal of a third wavelength and can reflect an optical signal of a fourth wavelength, and the optical signal of the third wavelength that is sent by the first optical transmitter is transmitted by the second light splitting film, then enters the second glass, and is refracted inside the second glass and then sent from the light emergent surface of the second glass. The optical signal of the fourth wavelength that is sent by the second optical transmitter enters the second glass, and is sequentially reflected by the second reflective film and the second light splitting film and then sent from the light emergent surface of the second glass, and an emergent position of the optical signal of the third wavelength overlaps an emergent position of the optical signal of the fourth wavelength.
In a possible implementation of the second aspect, a fourth reflective film is further disposed on the light incident surface of the second glass, and the fourth reflective film is disposed by keeping away from the optical transmitting path of the first optical transmitter and the optical transmitting path of the second optical transmitter, and is located between the optical transmitting path of the first optical transmitter and the optical transmitting path of the second optical transmitter. After the optical signal of the fourth wavelength enters the second glass, the optical signal is sequentially reflected between the third reflective film and the fourth reflective film and then enters the second light splitting film; and the optical signal of the fourth wavelength is reflected by the second light splitting film and then sent from the light emergent surface of the second glass. In this way, signal sending can be satisfied when the mounting spacing between the first optical transmitter and the second optical transmitter is relatively large.
In a possible implementation of the second aspect, the optical transmitting housing is a transistor-outline can, the transistor-outline can includes a header and a cap, the first optical transmitter and the second optical transmitter are both disposed on the header, and the second glass forms a transparent window of the cap.
In a possible implementation of the second aspect, the optical transmitting housing is a packaging box, a transparent window is formed on the packaging box, and the first optical transmitter, the second optical transmitter, and the second glass are all disposed in the packaging box; and the light emergent surface of the second glass is opposite to the transparent window of the packaging box. Therefore, a tilt angle and a position of the second glass may be finely adjusted in an active coupling manner, so that the second glass is disposed at a more precise position, and transmitting efficiency of the transmitter optical subassembly is higher.
According to a third aspect, this application provides a combo transceiver subassembly, including: a receiver optical subassembly, where the receiver optical subassembly is the receiver optical subassembly in any technical solution of the first aspect.
In a possible implementation of the third aspect, the combo transceiver subassembly further includes a combo package housing. An optical transmission channel is disposed in the combo package housing, and an optical demultiplexer is disposed in the optical transmission channel. An optical receive port, an optical transmit port, and an optical fiber connection port in communication with the optical transmission channel are disposed on the combo package housing. The receiver optical subassembly is packaged at the optical receive port. The optical demultiplexer can reflect, to the optical receive port, an optical signal of a first wavelength and an optical signal of a second wavelength that enter through the optical fiber connection port.
In a possible implementation of the third aspect, a transmitter optical subassembly is packaged at the optical transmit port, and the transmitter optical subassembly is the transmitter optical subassembly in any technical solution of the second aspect.
In a possible implementation of the third aspect, a first optical transmit port and a second optical transmit port are disposed on the combo package housing, a third optical transmitter is packaged at the first optical transmit port, a fourth optical transmitter is packaged at the second optical transmit port, and an optical multiplexer is disposed on the optical transmission channel. The optical multiplexer can combine an optical signal of a third wavelength that is sent by the third optical transmitter and an optical signal of a fourth wavelength that is sent by the fourth optical transmitter, and send the combined optical signals to the optical fiber connection port.
In a possible implementation of the third aspect, the optical multiplexer is a glass optical multiplexer, the optical signal of the third wavelength that is sent by the third optical transmitter is transmitted by the glass optical multiplexer and then enters the optical fiber connection port, and the optical signal of the fourth wavelength that is sent by the fourth optical transmitter is reflected by the glass optical multiplexer and then enters the optical fiber connection port.
In a possible implementation of the third aspect, a collimation lens is disposed at the optical fiber connection port.
According to a fourth aspect, this application provides a combo transceiver subassembly, including: a transmitter optical subassembly, where the transmitter optical subassembly is the transmitter optical subassembly in any technical solution of the second aspect.
According to a fifth aspect, this application provides a combo transceiver subassembly, including: a receiver optical subassembly, where the receiver optical subassembly is the receiver optical subassembly in any technical solution of the first aspect; and a transmitter optical subassembly, where the transmitter optical subassembly is the transmitter optical subassembly in any technical solution of the second aspect.
According to the combo transceiver subassembly provided in this embodiment of this application, the first glass is used, the first reflective film is disposed on the light incident surface of the first glass, and the first light splitting film is disposed on the light emergent surface. In addition, the first glass is disposed obliquely relative to the optical receiving paths of the first optical receiver and the second optical receiver. Therefore, after the optical signal of the first wavelength and the optical signal of the second wavelength are sent into the first glass along an optical receiving direction, the optical signal of the first wavelength may be transmitted through the first light splitting film and enter the first optical receiver, and the optical signal of the second wavelength is sequentially reflected by the first light splitting film and the first reflective film and then sent from the light emergent surface, and enters the second optical receiver. In this way, an emergent position of the optical signal of the second wavelength may be separated from an emergent position of the optical signal of the first wavelength by a specific distance, to meet a requirement for a mounting spacing between the first optical receiver and the second optical receiver, thereby implementing receiving of optical signals of different wavelengths based on the wavelengths. In addition, because a structure of disposing the light splitting film and the reflective film on the first glass is simple, production costs are low and mass production can be performed. In addition, the first glass occupies a small volume and a package structure is more compact, so that a packaging size requirement of an SFP+ is easily satisfied.
According to a sixth aspect, this application provides a combo optical module, including the receiver optical subassembly according to the first aspect, or including the transmitter optical subassembly according to the second aspect, or including an electrical subassembly and the combo transceiver subassembly in any technical solution of the third aspect, the fourth aspect, and the fifth aspect, where the electrical subassembly is electrically connected to a receiver optical subassembly and a transmitter optical subassembly of the combo transceiver subassembly.
According to a seventh aspect, this application provides a communications apparatus, including the combo optical module in the technical solution of the sixth aspect.
In a possible implementation of the seventh aspect, the communications apparatus is an optical line terminal or an optical network unit.
In a possible implementation of the seventh aspect, the optical line terminal further includes a board and a subrack that are used to place the combo optical module.
According to an eighth aspect, this application provides a passive optical network system, including: an optical line terminal, where the optical line terminal is the optical line terminal in any technical solution of the seventh aspect; an optical distribution network, where the optical distribution network is connected to the optical line terminal; and a plurality of optical network units, where the plurality of optical network units are connected to the optical distribution network.
In a possible implementation of the eighth aspect, optical modules of at least some of the plurality of optical network units are GPON optical modules, and optical modules of at least some of the plurality of optical network units are XGPON optical modules; or optical modules of at least some of the plurality of optical network units are EPON optical modules, and optical modules of at least some of the plurality of optical network units are 10G-EPON optical modules; or optical modules of at least some of the plurality of optical network units are the combo optical module in the technical solution of the sixth aspect.
It can be understood that when a non-combo optical module is used as the optical network unit, each optical module in the plurality of optical network units may include at least two of a GPON optical module, an XGPON optical module, a 25G-GPON optical module, and a 50G-GPON optical module, or each optical module in 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 combo optical module is used as the optical network unit, the combo optical module may simultaneously support any two of a GPON, an XGPON, a 25G GPON, and a 50G GPON, or simultaneously support any two of an EPON, a 10G EPON, a 25G EPON, and a 50G EPON.
According to the combo optical module, the communications apparatus, and the passive optical network system provided in the embodiments of this application, the first glass is used in the receiver optical subassembly, the first reflective film is disposed on the light incident surface of the first glass, and the first light splitting film is disposed on the light emergent surface. In addition, the first glass is disposed obliquely relative to the optical receiving paths of the first optical receiver and the second optical receiver. Therefore, after the optical signal of the first wavelength and the optical signal of the second wavelength are sent into the first glass along an optical receiving direction, the optical signal of the first wavelength may be transmitted through the first light splitting film and enter the first optical receiver, and the optical signal of the second wavelength is sequentially reflected by the first light splitting film and the first reflective film and then sent from the light emergent surface, and enters the second optical receiver. In this way, an emergent position of the optical signal of the second wavelength may be separated from an emergent position of the optical signal of the first wavelength by a specific distance, to meet a requirement for a mounting spacing between the first optical receiver and the second optical receiver, thereby implementing receiving of optical signals of different wavelengths based on the wavelengths. In addition, because a structure of disposing the light splitting film and the reflective film on the first glass is simple, production costs are low and mass production can be performed. In addition, the first glass occupies a small volume and a package structure is more compact, so that a packaging size requirement of an SFP+ is easily satisfied.
The embodiments of this application relate to a receiver optical subassembly, a transmitter optical subassembly, a combo transceiver subassembly, a combo optical module, and a passive optical network system. The following briefly describes concepts in the foregoing embodiments.
Passive optical network (PON): A passive optical network means that an optical distribution network (ODN) exists between an OLT and an ONU, and there is no active electronic device.
Optical distribution network (ODN): An ODN is a fiber-to-the-home optical cable network based on a PON device, and functions to provide an optical transmission channel between an OLT and an ONU.
Wavelength division multiplexing (WDM): Wavelength division multiplexing refers to a technology in which two or more optical carrier signals (carrying various information) of different wavelengths are combined at a transmit end by using a multiplexer (also referred to as an optical multiplexer), and coupled to a same optical fiber on an optical line for transmission. At a receive end, optical carriers of various wavelengths are separated by a demultiplexer (also referred to as an optical demultiplexer), and then an optical receiver further performs processing to restore original signals. This technology of simultaneously transmitting two or more optical signals of different wavelengths in a same optical fiber is referred to as wavelength division multiplexing.
Optical transmission module: referred to as an optical module for short, and including two parts: a bi-directional optical subassembly (BOSA) and an electrical subassembly (ESA). A pin of the bi-directional optical subassembly and a peripheral electrical subassembly (ESA) are electrically connected, and then mounted into an optical module housing, to form the optical transmission module.
The bidirectional optical subassembly (BOSA) mainly includes a transmitter optical subassembly (TOSA) and a receiver optical subassembly (ROSA).
The transmitter optical subassembly (TOSA): The TOSA functions to convert an electrical signal into an optical signal and input the optical signal into an optical fiber for transmission.
The receiver optical subassembly (ROSA): The ROSA functions to receive an optical signal transmitted from an optical fiber and convert the optical signal into an electrical signal.
An important subassembly of the optical module is the bidirectional optical subassembly (BOSA), which can be used to send and receive an optical signal. A typical BOSA structure is shown in
Due to material features of devices such as a transmitter (a laser diode) and a receiver (a photodiode), a separate TOSA and a separate ROSA are sensitive to water vapor and oxygen in an environment. If the TOSA and the ROSA are exposed to a corresponding gas, subassembly performance may deteriorate over time, causing a fault. Therefore, a transistor-outline can (TO CAN) is generally used for packaging, and an airtight process is adopted in a production process. A specific method is: in a pure nitrogen environment, a cap and a header are welded.
Specifically,
An external structure of a WDM module leads to high construction costs, large occupied equipment room space, complex construction and cabling, and difficult management and maintenance. Therefore, the WDM module may be embedded in the optical module.
The following uses a GPON as an example for description. An EPON scenario may be similar.
An optical module that can simultaneously support any two different transmission rates may be referred to as a combo optical module. For example, the combo optical module may simultaneously support any two of a GPON, an XGPON, a 25G GPON, and a 50G GPON, or simultaneously support any two of an EPON, a 10G EPON, a 25G EPON, and a 50G EPON. It can be understood that the combo optical module may also be referred to as an optical module.
For a wavelength of an optical signal, an optical line terminal in a GPON uses a wavelength of 1490 nm for transmitting and uses a wavelength of 1310 nm for receiving, and an optical line terminal in an XGPON uses a wavelength of 1577 nm for transmitting and uses a wavelength of 1270 nm for receiving. Then, in the combo transceiver subassembly, optical signals of these two wavelengths need to be received and sent, and coexist through a specific structure design. This requires a series of WDM modules (an optical multiplexer or an optical demultiplexer) to combine and separate light of the two wavelengths. In addition, it should be considered that a specific narrow-band filter should be used before a receiver, to further filter out other possible stray light. For example, A 0° filter that can allow only a 1270 band to pass through can be placed before a 1270-nm receiver, and a 0° filter that can allow only a 1310 band to pass through can be placed before a 1310-nm receiver.
The receiver optical subassembly implements light splitting by using the optical lens group 035. Although relatively small-scale packaging can be implemented, the optical lens group 035 is difficult to produce, costs are high, a processing technique requirement is high, and mass production is difficult. In addition, the optical lens group 035 has a relatively large volume, and it is difficult to satisfy a packaging size requirement of small form-factor pluggables (SFP+).
To resolve the foregoing problem, as shown in
According to the receiver optical subassembly provided in this embodiment of this application, the first glass 4 is used, the first reflective film 44 is disposed on the light incident surface 41 of the first glass 4, and the first light splitting film 43 and the second reflective film 45 are disposed on the light emergent surface 42. In addition, the first glass 4 is disposed obliquely relative to the optical receiving paths. Therefore, after the optical signal of the first wavelength and the optical signal of the second wavelength are sent into the first glass 4 along an optical receiving direction, the optical signal of the first wavelength may be transmitted through the first light splitting film 43 and enter the first optical receiver 2, and the optical signal of the second wavelength is sequentially reflected by the first light splitting film 43 and the first reflective film 44 and then sent from the light emergent surface 42, and enters the second optical receiver 3. In this way, an emergent position of the optical signal of the second wavelength may be separated from an emergent position of the optical signal of the first wavelength by a specific distance, thereby implementing receiving of optical signals of different wavelengths based on the wavelengths. In addition, because a structure of disposing the light splitting film and the reflective film on the first glass 4 is simple, production costs are low and mass production can be performed. In addition, the first glass 4 occupies a small volume and a package structure is more compact, so that a packaging size requirement of an SFP+ is easily satisfied.
When a mounting spacing between the first optical receiver 2 and the second optical receiver 3 is relatively large, a second reflective film 45 may be further disposed on the light emergent surface 42 of the first glass 4, and the second reflective film 45 is disposed by keeping away from the optical receiving path of the second optical receiver 3. In addition, the second reflective film 45 is located between the optical receiving path of the first optical receiver 2 and the optical receiving path of the second optical receiver 3. After the optical signal of the second wavelength is reflected by the first light splitting film 43, the optical signal is reflected between the first reflective film 44 and the second reflective film 45 for a plurality of times to keep a specific distance, and finally sent from the light emergent surface 42 and enters the second optical receiver 3. For example, after being reflected by the first light splitting film 43, the optical signal of the second wavelength may be sequentially reflected by the first reflective film 44 and the second reflective film 45, and is sent from the light emergent surface 42 after being reflected by the first reflective film 44. To be specific, the optical signal of the second wavelength is reflected by the first reflective film 44 twice and is reflected by the second reflective film 45 once. Alternatively, as shown in
Specifically, an optical signal of a wavelength of 1310±20 nanometers and an optical signal of a wavelength of 1270±10 nanometers are usually used as received signals, and the wavelengths of the two signals are relatively close to each other. As can be known according to the Fresnel reflection principle, when an angle of incidence of incident light is larger, a width of a guard band becomes wider, and a center wavelength shift caused by a change of the angle of incidence is larger. Therefore, when the center wavelength shift occurs, crosstalk easily occurs between the optical signal of the wavelength of 1310±20 nanometers and the optical signal of the wavelength of 1270±10 nanometers, where the wavelengths are similar. To resolve the foregoing problem, an angle of incidence of incident light may be appropriately decreased. To be specific, an angle of incidence a at which the optical signal of the first wavelength and the optical signal of the second wavelength are sent into the first glass 4 is set to be less than 12°. In addition, if the angle of incidence a is excessively small, a reflection angle at which the optical signal of the second wavelength is reflected between the first reflective film 44 and the second reflective film 45 is relatively small, and the optical signal of the second wavelength needs to be reflected for more times to keep a sufficient distance, to satisfy a requirement on a mounting spacing between the first optical receiver 2 and the second optical receiver 3. Reflection for more times causes a relatively large signal loss. Therefore, the angle of incidence a may be set to 8° to 12°. When the angle of incidence a is set to fall within the foregoing range, not only light splitting isolation is ensured, but also a loss of the optical signal of the second wavelength may be controlled within 0.3 dB.
A thickness of the first glass 4 may be selected as 0.2 to 2 millimeters. In an embodiment of this application, the thickness of the first glass 4 may be 1.6 millimeters. Therefore, producing difficulty and costs are low, and an overall size may easily satisfy a packaging size requirement of an SFP+.
As shown in
To increase transmission intensity of the optical signal, an antireflective film (not shown in the figure) may be disposed on the light emergent surface 42 of the first glass 4, thereby reducing reflection intensity of the optical signal and increasing transmission intensity of the optical signal.
In an embodiment of this application, the receiver optical subassembly may be packaged by using a transistor-outline can. Specifically, as shown in
In another embodiment of this application, the receiver optical subassembly may be alternatively packaged by using box packaging. Specifically, as shown in
As shown in
According to the combo transceiver subassembly provided in this embodiment of the application, the optical signal of the first wavelength and the optical signal of the second wavelength transmitted by the optical fiber connection port 105 are reflected when passing through the optical demultiplexer 102, and the receiver optical subassembly is exactly on a light reflecting path, to receive the optical signal. The first glass 4 is used in the receiver optical subassembly, the first reflective film 44 is disposed on the light incident surface 41 of the first glass 4, and the first light splitting film 43 and the second reflective film 45 are disposed on the light emergent surface 42. In addition, the first glass 4 is disposed obliquely relative to the optical receiving paths. Therefore, after the optical signal of the first wavelength and the optical signal of the second wavelength are sent into the first glass 4 along an optical receiving direction, the optical signal of the first wavelength may be transmitted through the first light splitting film 43 and enter the first optical receiver 2, and the optical signal of the second wavelength is sequentially reflected by the first light splitting film 43 and the first reflective film 44 and then sent from the light emergent surface 42, and enters the second optical receiver 3. In this way, an emergent position of the optical signal of the second wavelength may be separated from an emergent position of the optical signal of the first wavelength by a specific distance, thereby implementing receiving of optical signals of different wavelengths based on the wavelengths. In addition, because a structure of disposing the light splitting film and the reflective film on the first glass 4 is simple, production costs are low and mass production can be performed. In addition, the first glass 4 occupies a small volume and a package structure is more compact, so that a packaging size requirement of an SFP+ is easily satisfied.
Specifically, the package structure may be shown in
In an embodiment of the combo transceiver subassembly of this application, as shown in
To reduce impact of reflected light in a network on performance of the transmitter optical subassembly, as shown in
A structure of the transmitter optical subassembly 107 may be shown in
When a mounting spacing between the first optical transmitter 71 and the second optical transmitter 72 is relatively large, a fourth reflective film 85 may be further added on the light incident surface of the second glass 8. The fourth reflective film 85 is disposed by keeping away from the optical transmitting path of the first optical transmitter 71 and the optical transmitting path of the second optical transmitter 72, and is located between the optical transmitting path of the first optical transmitter 71 and the optical transmitting path of the second optical transmitter 72. After entering the second glass 8, the optical signal of the fourth wavelength is sequentially reflected between the third reflective film 84 and the fourth reflective film 85 for a plurality of times, and then enters the second light splitting film 83. The optical signal of the fourth wavelength is reflected by the second light splitting film 83 and then sent by the light emergent surface 82 of the second glass 8.
As shown in
To increase transmission intensity of the optical signal, an antireflective film (not shown in the figure) may be disposed on the light incident surface 41 of the first glass 4, thereby reducing reflection intensity of the optical signal and increasing transmission intensity of the optical signal.
Specifically, as shown in
The transmitter optical subassembly may be alternatively packaged in a box packaging manner. Specifically, as shown in
In another embodiment of the combo transceiver subassembly in this application, as shown in
Specifically, as shown in
It should be noted that, when incident optical signals include optical signals of different wavelengths such as three, four, and five wavelengths, the solution of the receiver optical subassembly in this application is also applicable, and only a quantity of optical receivers and a quantity of light splitting films need to be correspondingly increased. For example, when incident optical signals include the optical signal of the first wavelength, the optical signal of the second wavelength, and an optical signal of a fifth wavelength, as shown in
When the spacing between the second optical receiver 3 and the third optical receiver 3′ is relatively large, a fifth reflective film 47 can also be added on the light emergent surface 42. The fifth reflecting film 47 avoids an optical receiving path of the second optical receiver 3 and an optical receiving path of the third optical receiver 3′, and is located between the optical receiving path of the second optical receiver 3 and the optical receiving path of the third optical receiver 3′. The optical signal of the fifth wavelength is reflected between the first reflecting film 44 and the fifth reflecting film 47 for a plurality of times and then is sent from the light emergent surface 42 and enters the third optical receiver 3′.
Alternatively, a third collector lens 53 may be disposed between the light emergent surface 42 of the first glass 4 and the third optical receiver 3′, and the third collector lens 53 is configured to concentrate the optical signal of the fifth wavelength in the third optical receiver 3′.
Similarly, when sent optical signals include optical signals of different wavelengths such as three, four, or five wavelengths, the solution of the transmitter optical subassembly of this application is also applicable. For example, when the optical signal of the third wavelength, the optical signal of the fourth wavelength, and an optical signal of a sixth wavelength need to be sent, as shown in
To correct a transmission direction of the optical signal of the sixth wavelength, a third collimation lens 93 may be further disposed between the light emergent surface 82 of the second glass 8 and the fifth optical transmitter 76, and the third collimation lens 93 is configured to convert the optical signal of the sixth wavelength into collimated light.
The combo transceiver subassembly in any one of the foregoing embodiments and a peripheral electrical subassembly (ESA) are electrically connected, and then mounted into an optical module housing, to form a combo optical module.
The combo optical module is connected to a board and placed in a subrack, to form an optical line terminal.
Similarly, the combo optical module may be applied to 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 optical line terminal; an optical distribution network, where the optical distribution network is connected to the optical line terminal; and a plurality of optical network units, where the plurality of optical network units are connected to the optical distribution network.
According to the combo optical module, the optical transmission module, and the passive optical network system provided in the embodiments of this application, the first glass 4 is used in the receiver optical subassembly, the first reflective film 44 is disposed on the light incident surface 41 of the first glass 4, and the first light splitting film 43 and the second reflective film 45 are disposed on the light emergent surface 42. In addition, the first glass 4 is disposed obliquely relative to the optical receiving paths. Therefore, after the optical signal of the first wavelength and the optical signal of the second wavelength are sent into the first glass 4 along an optical receiving direction, the optical signal of the first wavelength may be transmitted through the first light splitting film 43 and enter the first optical receiver 2, and the optical signal of the second wavelength is sequentially reflected by the first light splitting film 43 and the first reflective film 44 and then sent from the light emergent surface 42, and enters the second optical receiver 3. In this way, an emergent position of the optical signal of the second wavelength may be separated from an emergent position of the optical signal of the first wavelength by a specific distance, thereby implementing receiving of optical signals of different wavelengths based on the wavelengths. In addition, because a structure of disposing the light splitting film and the reflective film on the first glass 4 is simple, production costs are low and mass production can be performed. In addition, the first glass 4 occupies a small volume and a package structure is more compact, so that a packaging size requirement of an SFP+ is easily satisfied.
Optical modules of at least some of the plurality of optical network units may be GPON optical modules, and optical modules of at least some of the plurality of optical network units may be XGPON optical modules; or optical modules of at least some of the plurality of optical network units may be EPON optical modules, and optical modules of at least some of the plurality of optical network units may be 10G-EPON optical modules; or optical modules of at least some of the plurality of optical network units are the foregoing combo optical module.
In the descriptions of this specification, the specific features, structures, materials, or characteristics may be combined in a proper manner in any one or more of the embodiments or examples.
The foregoing descriptions are merely specific implementations of the present invention, but are not intended to limit the protection scope of the present invention. Any variation or replacement readily figured out by a person skilled in the art within the technical scope disclosed in the present invention shall fall within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
This application is a continuation of International Application No. PCT/CN2018/102564, filed on Aug. 27, 2018, the disclosure of which is hereby incorporated by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/CN2018/102564 | Aug 2018 | US |
| Child | 17158738 | US |
