CN218352504U - Optical module - Google Patents

Abstract

The application provides an optical module, which comprises a laser, an MCU, a digital-to-analog converter, a modulation driver, a coherent light assembly and a voltage monitor, wherein the laser is used for outputting light; the MCU comprises a temperature sensor and is used for acquiring the current temperature; the MCU receives the feedback PKD voltage, and adjusts the output electric signal through the feedback PKD voltage when the temperature changes; the digital-to-analog converter receives the electric signal sent by the MCU and outputs VG voltage; the modulation driver receives VG voltage sent by the digital-to-analog converter and outputs driving voltage; the coherent light component receives light generated by the laser and a driving voltage sent by the modulation driver, and changes the emitted light power of the optical signal under the action of the driving voltage; the voltage monitor monitors the driving voltage output by the modulation driver and feeds the PKD voltage back to the MCU. When the temperature changes, the MCU adjusts the VG voltage through the fed-back PKD voltage, so that the light emitting power of the coherent optical module keeps consistent at different temperatures.

Description

Optical module

Technical Field

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

Background

In the optical communication, an optical module is a tool for realizing the interconversion of photoelectric signals, and is one of key components in optical communication equipment. With the rapid development of the 5G network, the optical module at the core position of optical communication has been developed greatly.

For the coherent optical module, the control principle of the transmitting end of the coherent optical module is that the coherent optical module passes a beam of linearly polarized light through a modulator, and then loads four paths of data signals output by a Digital Signal Processing (DSP) onto the linearly polarized light to form modulated light for transmission, so that the modulated light is emitted at a certain light emitting power; the light emitting power of the coherent light module changes greatly at different temperatures, for example, when the temperature is low, the light emitting power of the coherent light module is high, and when the temperature is high, the light emitting power of the coherent light module is low, so that the light emitting powers of the coherent light module are inconsistent in different use environments of customers.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides an optical module, so that the emitted light power of a coherent optical module is kept consistent at different temperatures.

The application provides an optical module, including:

a circuit board;

the laser is electrically connected with the circuit board and used for outputting light;

the MCU is electrically connected with the circuit board and comprises a temperature sensor, and the temperature sensor is used for acquiring the current temperature; the PKD voltage is used for receiving feedback, and the output electric signal is adjusted through the feedback PKD voltage when the temperature changes;

the digital-to-analog converter is electrically connected with the MCU and used for receiving the electric signal and outputting VG voltage;

the modulation driver is electrically connected with the digital-to-analog converter and used for receiving the VG voltage and outputting a driving voltage;

the coherent light component is electrically connected with the modulation driver, is connected with the laser, and is used for receiving the light and the driving voltage and changing the emitted light power of the optical signal under the action of the driving voltage;

and the voltage monitor is electrically connected with the modulation driver and the MCU and used for monitoring the driving voltage and feeding the PKD voltage back to the MCU.

As can be seen from the above embodiments, the optical module provided in the embodiments of the present application includes a circuit board, a laser, an MCU, a digital-to-analog converter, a modulation driver, a coherent optical component, and a voltage monitor, where the laser is electrically connected to the circuit board and is used to output light; the MCU comprises a temperature sensor, the temperature sensor is used for collecting the current temperature, and the MCU adjusts the output electric signal when the temperature changes; the digital-to-analog converter is electrically connected with the MCU, receives the electric signal sent by the MCU and outputs VG voltage; the modulation driver is electrically connected with the digital-to-analog converter, receives VG voltage provided by the digital-to-analog converter, processes the VG voltage and then outputs driving voltage, and the driving voltage is related to the VG voltage; the coherent light component is electrically connected with the modulation driver, is connected with the laser, and receives the light output by the laser and the driving voltage provided by the modulation driver so as to change the emitted light power of the optical signal under the action of the driving voltage; the voltage monitor is electrically connected with the modulation driver and the MCU and is used for monitoring the driving voltage output by the modulation driver, obtaining the PKD voltage according to the driving voltage and feeding back the PKD voltage to the MCU. Therefore, when the temperature changes, the MCU adjusts the output electric signal, changes the VG voltage input by the modulation driver and the output driving voltage, the voltage monitor monitors the driving voltage output by the modulation driver, obtains the PKD voltage according to the driving voltage, and feeds the PKD voltage back to the MCU, and the MCU continues to adjust the output electric signal according to the fed-back PKD voltage so as to adjust the VG voltage input by the modulation driver, so that the emitted light power of the optical signal is changed, and the light-emitting power of the coherent optical module is kept consistent at different temperatures.

Drawings

In order to more clearly illustrate the technical solutions in the present disclosure, the drawings needed to be used in some embodiments of the present disclosure will be briefly described below, and it is apparent that the drawings in the following description are only drawings of some embodiments of the present disclosure, and other drawings can be obtained by those skilled in the art according to the drawings. Furthermore, the drawings in the following description may be regarded as schematic diagrams, and do not limit the actual size of products, the actual flow of methods, the actual timing of signals, and the like, involved in the embodiments of the present disclosure.

FIG. 1 is a connection diagram of an optical communication system according to some embodiments;

FIG. 2 is a block diagram of a light module according to some embodiments;

FIG. 3 is a block diagram of a light module according to some embodiments;

FIG. 4 is a partially exploded schematic view of a light module according to some embodiments;

fig. 5 is an assembly schematic diagram of a circuit board, an optical module, and an optical fiber adapter in an optical module according to an embodiment of the present disclosure;

fig. 6 is a schematic partial assembly diagram of a circuit board and an optical module in an optical module according to an embodiment of the present disclosure;

fig. 7 is a first block diagram of a structure on a circuit board in an optical module according to an embodiment of the present disclosure;

fig. 8 is a second block diagram of a structure on a circuit board in an optical module according to an embodiment of the present disclosure;

fig. 9 is a block diagram of a structure on a circuit board in an optical module according to an embodiment of the present application;

fig. 10 is a graph illustrating a relationship curve between VG voltage and temperature of an optical module according to an embodiment of the present disclosure.

Detailed Description

Technical solutions in some embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings, and it is obvious that the described embodiments are only a part of the embodiments of the present disclosure, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments provided by the present disclosure belong to the protection scope of the present disclosure.

In an optical communication system, an optical signal is used to carry information to be transmitted, and the optical signal carrying the information is transmitted to information processing equipment such as a computer through information transmission equipment such as an optical fiber or an optical waveguide, so as to complete information transmission. Since light has a passive transmission characteristic when transmitted through an optical fiber or an optical waveguide, low-cost, low-loss information transmission can be realized. Since a signal transmitted by an information transmission device such as an optical fiber or an optical waveguide is an optical signal and a signal that can be recognized and processed by an information processing device such as a computer is an electrical signal, it is necessary to perform interconversion between the electrical signal and the optical signal in order to establish information connection between the information transmission device such as an optical fiber or an optical waveguide and the information processing device such as a computer.

The optical module realizes the function of interconversion between the optical signal and the electrical signal in the technical field of optical communication. The optical module comprises an optical port and an electric port, the optical module realizes optical communication with information transmission equipment such as optical fibers or optical waveguides and the like through the optical port, realizes electric connection with an optical network terminal (such as an optical modem) through the electric port, and the electric connection is mainly used for power supply, I2C signal transmission, data information transmission, grounding and the like; the optical network terminal transmits the electric signal to the computer and other information processing equipment through a network cable or a wireless fidelity (Wi-Fi).

Fig. 1 is a connection diagram of an optical communication system. As shown in fig. 1, the optical communication system includes a remote server 1000, a local information processing device 2000, an optical network terminal 100, an optical module 200, an optical fiber 101, and a network cable 103.

One end of the optical fiber 101 is connected to the remote server 1000, and the other end is connected to the optical network terminal 100 through the optical module 200. The optical fiber itself can support long-distance signal transmission, for example, signal transmission of several kilometers (6 kilometers to 8 kilometers), on the basis of which if a repeater is used, theoretically, infinite distance transmission can be realized. Therefore, in a typical optical communication system, the distance between the remote server 1000 and the optical network terminal 100 may be several kilometers, tens of kilometers, or hundreds of kilometers.

One end of the network cable 103 is connected to the local information processing device 2000, and the other end is connected to the optical network terminal 100. The local information processing device 2000 may be any one or several of the following devices: router, switch, computer, cell-phone, panel computer, TV set etc..

The physical distance between the remote server 1000 and the optical network terminal 100 is greater than the physical distance between the local information processing apparatus 2000 and the optical network terminal 100. The connection between the local information processing apparatus 2000 and the remote server 1000 is made by the optical fiber 101 and the network cable 103; and the connection between the optical fiber 101 and the network cable 103 is completed by the optical module 200 and the optical network terminal 100.

The optical module 200 includes an optical port configured to access the optical fiber 101 and an electrical port, so that the optical module 200 establishes a bidirectional optical signal connection with the optical fiber 101; the electrical port is configured to be plugged into the optical network terminal 100 so that the optical module 200 establishes a bi-directional electrical signal connection with the optical network terminal 100. The optical module 200 converts an optical signal and an electrical signal to each other, so that an information connection is established between the optical fiber 101 and the optical network terminal 100. For example, an optical signal from the optical fiber 101 is converted into an electrical signal by the optical module 200 and then input to the optical network terminal 100, and an electrical signal from the optical network terminal 100 is converted into an optical signal by the optical module 200 and input to the optical fiber 101. Since the optical module 200 is a tool for implementing the interconversion between the optical signal and the electrical signal, and has no function of processing data, information is not changed in the above-mentioned photoelectric conversion process.

The optical network terminal 100 includes a housing (housing) having a substantially rectangular parallelepiped shape, and an optical module interface 102 and a network cable interface 104 provided on the housing. The optical module interface 102 is configured to access the optical module 200, so that the optical network terminal 100 establishes a bidirectional electrical signal connection with the optical module 200; the network cable interface 104 is configured to access the network cable 103 such that the optical network terminal 100 establishes a bi-directional electrical signal connection with the network cable 103. The optical module 200 is connected to the network cable 103 via the optical network terminal 100. For example, the optical network terminal 100 transmits the electrical signal from the optical module 200 to the network cable 103, and transmits the electrical signal from the network cable 103 to the optical module 200, so that the optical network terminal 100 can monitor the operation of the optical module 200 as an upper computer of the optical module 200. The upper computer of the Optical module 200 may include an Optical Line Terminal (OLT) and the like in addition to the Optical network Terminal 100.

The remote server 1000 establishes a bidirectional signal transmission channel with the local information processing device 2000 through the optical fiber 101, the optical module 200, the optical network terminal 100, and the network cable 103.

Fig. 2 is a configuration diagram of the optical network terminal, and fig. 2 only shows a configuration of the optical module 200 of the optical network terminal 100 in order to clearly show a connection relationship between the optical module 200 and the optical network terminal 100. As shown in fig. 2, the optical network terminal 100 further includes a circuit board 105 disposed within the housing, a cage 106 disposed on a surface of the circuit board 105, a heat sink 107 disposed on the cage 106, and an electrical connector disposed inside the cage 106. The electrical connector is configured to access an electrical port of the optical module 200; the heat sink 107 has a projection such as a fin that increases a heat radiation area.

The optical module 200 is inserted into a cage 106 of the optical network terminal 100, the cage 106 holds the optical module 200, and heat generated by the optical module 200 is conducted to the cage 106 and then diffused by a heat sink 107. After the optical module 200 is inserted into the cage 106, the electrical port of the optical module 200 is connected to the electrical connector inside the cage 106, so that the optical module 200 is connected to the optical network terminal 100 by a bidirectional electrical signal. Further, an optical port of the optical module 200 is connected to the optical fiber 101, and the optical module 200 establishes bidirectional optical signal connection with the optical fiber 101.

Fig. 3 is a block diagram of a light module according to some embodiments, and fig. 4 is an exploded view of a light module according to some embodiments. As shown in fig. 3 and 4, the optical module 200 includes a housing (shell), a circuit board 300 disposed in the housing, and an optical assembly 400.

The shell comprises an upper shell 201 and a lower shell 202, wherein the upper shell 201 is covered on the lower shell 202 to form the shell with two openings; the outer contour of the housing generally appears square.

In some embodiments of the present disclosure, the lower housing 202 includes a bottom plate and two lower side plates located at both sides of the bottom plate and disposed perpendicular to the bottom plate; the upper case 201 includes a cover plate covering both lower side plates of the lower case 202 to form the above case.

In some embodiments, the lower housing 202 includes a bottom plate and two lower side plates disposed at both sides of the bottom plate and perpendicular to the bottom plate; the upper housing 201 includes a cover plate and two upper side plates disposed on two sides of the cover plate and perpendicular to the cover plate, and the two upper side plates are combined with the two lower side plates to cover the upper housing 201 on the lower housing 202.

The direction of the connecting line of the two openings 204 and 205 may be the same as the length direction of the optical module 200, or may not be the same as the length direction of the optical module 200. For example, the opening 204 is located at an end portion (left end in fig. 3) of the optical module 200, and the opening 205 is also located at an end portion (right end in fig. 3) of the optical module 200. Alternatively, the opening 204 is located at an end of the optical module 200, and the opening 205 is located at a side of the optical module 200. The opening 204 is an electrical port from which a gold finger of the circuit board 300 extends and is inserted into an upper computer (e.g., the optical network terminal 100); the opening 205 is an optical port configured to access the external optical fiber 101, so that the external optical fiber 101 is connected to an optical transceiver module inside the optical module 200.

The upper shell 201 and the lower shell 202 are combined in an assembly mode, so that the circuit board 300, the optical assembly 400 and other devices can be conveniently installed in the shells, and the upper shell 201 and the lower shell 202 form encapsulation protection for the devices. In addition, when the devices such as the circuit board 300 and the optical assembly 400 are assembled, the positioning components, the heat dissipation components and the electromagnetic shielding components of the devices are convenient to deploy, and the automatic production is facilitated.

In some embodiments, the upper housing 201 and the lower housing 202 are generally made of metal materials, which is beneficial to achieve electromagnetic shielding and heat dissipation.

In some embodiments, the optical module 200 further includes an unlocking part 203 located outside the housing thereof, and the unlocking part 203 is configured to realize a fixed connection between the optical module 200 and the upper computer or release the fixed connection between the optical module 200 and the upper computer.

Illustratively, the unlocking member 203 is located on the outer walls of the two lower side plates of the lower housing 202, and has a snap-fit member that mates with a host cage (e.g., the cage 106 of the optical network terminal 100). When the optical module 200 is inserted into the cage of the upper computer, the optical module 200 is fixed in the cage of the upper computer by the engaging member of the unlocking member 203; when the unlocking member 203 is pulled, the engaging member of the unlocking member 203 moves along with the unlocking member, and the connection relationship between the engaging member and the upper computer is changed, so that the engagement relationship between the optical module 200 and the upper computer is released, and the optical module 200 can be drawn out from the cage of the upper computer.

The circuit board 300 includes circuit traces, electronic components, and chips, and the electronic components and the chips are connected together by the circuit traces according to a circuit design to implement functions of power supply, electrical signal transmission, grounding, and the like. Examples of the electronic components include capacitors, resistors, transistors, and Metal-Oxide-Semiconductor Field-Effect transistors (MOSFETs). The chip includes, for example, a Micro Controller Unit (MCU), a laser driving chip, a limiting amplifier (limiting amplifier), a Clock and Data Recovery (CDR) chip, a power management chip, and a Digital Signal Processing (DSP) chip.

The circuit board 300 is generally a rigid circuit board, which can also perform a bearing function due to its relatively rigid material, for example, the rigid circuit board can stably bear the electronic components and chips; when the optical transceiver component is positioned on the circuit board, the rigid circuit board can also provide smooth bearing; the rigid circuit board can also be inserted into an electric connector in the cage of the upper computer.

The circuit board 300 further includes a gold finger 301 formed on an end surface thereof, the gold finger 301 being composed of a plurality of pins independent of each other. The circuit board 300 is inserted into the cage 106, and electrically connected to an electrical connector in the cage 106 by gold fingers 301. The gold finger 301 may be disposed on only one side surface (e.g., the front surface shown in fig. 4) of the circuit board 300, or may be disposed on both upper and lower surfaces of the circuit board 300, so as to adapt to the situation where the requirement of the number of pins is large. The golden finger is configured to establish an electrical connection with the upper computer to realize power supply, grounding, I2C signal transmission, data signal transmission and the like.

Of course, a flexible circuit board is also used in some optical modules. Flexible circuit boards are commonly used in conjunction with rigid circuit boards to supplement the rigid circuit boards. For example, a flexible circuit board may be used to connect the rigid circuit board and the optical transceiver module.

Fig. 5 is an assembly schematic diagram of a circuit board, an optical component, and an optical fiber adapter in an optical module provided in the embodiment of the present application, and fig. 6 is a partial assembly schematic diagram of the circuit board and the optical component in the optical module provided in the embodiment of the present application. As shown in fig. 5 and 6, the optical assembly 400 generally includes a silicon optical chip and an electrical chip, and the silicon optical chip, the electrical chip and the circuit board are packaged to realize signal transmission among the circuit board, the electrical chip and the silicon optical chip. The silicon optical chip is provided with a light source inlet, an optical fiber inlet and an optical fiber outlet, wherein the light source inlet corresponds to the light source 500, so that light generated by the light source 500 is emitted into the silicon optical chip through the light source inlet, the light inside the silicon optical chip is modulated to generate an optical signal, the optical signal is transmitted to the emission optical fiber coupler 610 through the optical fiber outlet, the emission optical fiber coupler 610 couples the optical signal output by the silicon optical chip to the internal optical fiber, and then the optical signal is coupled to the optical fiber adapter 700 through the internal optical fiber to realize the emission of the light.

The optical fiber adapter 700 is connected with the receiving optical fiber coupler 620 through the internal optical fiber, and the receiving optical fiber coupler 620 is connected with the optical fiber inlet, so that an external optical signal transmitted by the optical fiber adapter 700 is transmitted into the silicon optical chip through the internal optical fiber, the receiving optical fiber coupler 620 and the optical fiber inlet, the silicon optical chip converts the optical signal into an electrical signal, the electrical signal is transmitted to the circuit board 300, and the electrical signal is transmitted to an upper computer through the golden finger 301 on the circuit board 300, so as to realize the light receiving.

In some embodiments, the circuit board 300 is provided with an MCU and a DSP chip, and the MCU is electrically connected to the gold finger 301 through a signal line to transmit the electrical signal transmitted by the gold finger 301 to the MCU through the signal line; the MCU is electrically connected with the silicon optical chip through a signal wire so as to send a driving voltage to the silicon optical chip; the DSP chip is connected with the silicon optical chip through a signal wire so as to send a data signal to the silicon optical chip; the silicon optical chip modulates the data signal to the light emitted by the light source 500 under the action of the driving voltage to obtain a modulated optical signal, and the optical signal is coupled to the optical fiber adapter 700 through the emission optical fiber coupler 610 to realize the emission of the light.

In some embodiments, with the development of an optical module, especially a coherent optical module, a control principle of a transmitting end of the coherent optical module is that the coherent optical module passes a beam of local oscillator light (light emitted by a light source 500) through a coherent optical component in a silicon optical chip, then four paths of data signals output by a DSP chip are loaded onto linearly polarized light for modulation, and the modulated optical signal is emitted at a certain light emitting power. The change of the light emitting power of the coherent optical module is large at different temperatures, for example, when the temperature is low, the light emitting power of the coherent optical module is high, and when the temperature is high, the light emitting power of the coherent optical module is low, so that the light emitting power of the coherent optical module is inconsistent in different use environments of a customer, and the stability of the light emitting power is difficult to ensure.

In order to solve the above problem, an embodiment of the present application provides an optical module, where an MCU in the optical module receives a fed-back PKD voltage, and when a temperature of the MCU changes, the MCU adjusts an output current signal according to the fed-back PKD voltage to adjust a VG voltage, so as to change a light emitting power of an optical signal, so that light emitting powers of coherent optical modules are kept consistent at different temperatures.

Fig. 7 is a first block diagram of a structure on a circuit board in an optical module according to an embodiment of the present application, and fig. 8 is a second block diagram of a structure on a circuit board in an optical module according to an embodiment of the present application. As shown in fig. 7 and 8, an optical module provided in the embodiment of the present application includes a modulation driver, a silicon optical chip, and a voltage monitor, where a coherent optical component is disposed in the silicon optical chip, and receives light emitted by a light source 500; the modulation driver is electrically connected with the MCU on the circuit board 300 to receive VG voltage provided by the MCU, and the modulation driver processes the VG voltage and outputs driving voltage; the coherent light assembly is electrically connected to the modulation driver, and is configured to receive light emitted by the light source 500 and a driving voltage output by the modulation driver, and change the emitted light power of the optical signal under the action of the driving voltage.

Specifically, the light source 500 may be a laser, narrow-spectrum light emitted by the laser is transmitted into a coherent light assembly of a silicon optical chip, one light beam is split into two light beams by a beam splitter on the silicon optical chip, and the two light beams are respectively transmitted to two modulation walls of the coherent light assembly; the MCU provides VG voltage for the modulation driver, and the modulation driver generates driving voltage according to the VG voltage, and the driving voltage acts on the modulation wall of the coherent light component; the data signal output by the DSP chip is transmitted to two modulation walls of the coherent light component, and the modulation walls perform phase modulation on the optical signal under the action of driving voltage, so that the transmitting optical power of the optical signal is changed.

In some embodiments, the electrical signal output by the MCU is a digital electrical signal, and the electrical signal received by the modulation driver is an analog electrical signal, so that the optical module provided in this embodiment further includes a digital-to-analog converter, one end of the digital-to-analog converter is electrically connected to the MCU, and the other end of the digital-to-analog converter is electrically connected to the modulation driver, so that the digital-to-analog converter converts the digital electrical signal output by the MCU into an analog electrical signal and transmits the analog electrical signal to the modulation driver, so as to provide VG voltage to the modulation driver.

When the electric signals output by the MCU are different, the modulation driver inputs different VG voltages and outputs different driving voltages, and the coherent light component has different emitting light powers under the action of the different driving voltages.

In some embodiments, when the optical module is at different ambient temperatures, the MCU outputs different current signals, the different current signals are converted into analog current signals by the digital-to-analog converter, and different VG voltages are output to the modulation driver, and the modulation driver outputs different driving voltages, and the coherent optical component has different emitted optical powers at different driving voltages, so that the optical module has different emitted optical powers at different temperatures.

Fig. 9 is a block diagram of a structure on a circuit board in an optical module according to the embodiment of the present application. As shown in fig. 9, in order to ensure that the emitted light power of the optical module is consistent at different temperatures, the MCU includes a temperature sensor, a first register, a second register, a comparator and a controller, the temperature sensor is used to collect the current temperature, a relationship table between VG voltage and temperature is stored in the first register, that is, at different temperatures, VG voltage values input by the modulation driver are recorded, the modulation driver outputs a driving voltage according to the input VG voltage, the coherent light module emits the light signal at a preset light power under the action of the driving voltage, and thus VG voltage values at different temperatures are recorded, and a relationship table between VG voltage and temperature is formed.

In some embodiments, when the ambient temperature of the optical module is obtained in real time, a temperature sensor may be further disposed in the optical module, and temperature data detected by the temperature sensor is sent to the MCU, that is, the optical module provided in the embodiment of the present application further includes the temperature sensor disposed on the circuit board 300, and the temperature sensor is electrically connected to the MCU, the temperature sensor is configured to collect the ambient temperature of the coherent optical component, and send the collected temperature data to the MCU, the MCU reads a relationship table between VG voltage and temperature from the first register, obtains a theoretical VG voltage value at the current temperature according to the relationship table, and adjusts an output electrical signal according to the theoretical VG voltage value.

Specifically, according to 3 points of a temperature point, namely high temperature, low temperature and normal temperature, VG voltage values corresponding to the 3 points are recorded, the 3 temperature points and the corresponding VG voltage values are stored in a first register of the MCU, and a relationship table of VG voltage and temperature is formed in the first register, that is, the relationship table of VG voltage and temperature includes VG voltage values at low temperature, VG voltage values at normal temperature and VG voltage values at high temperature.

In some embodiments, the voltage value of VG is inversely proportional to the temperature, and gradually decreases as the temperature gradually increases. Namely, the VG voltage value at low temperature is larger than the VG voltage value at normal temperature, and the VG voltage value at normal temperature is larger than the VG voltage value at high temperature.

Fig. 10 is a schematic diagram of a relationship curve between VG voltage and temperature of the optical module according to the embodiment of the present application. As shown in fig. 10, since the VG voltage value is inversely proportional to the temperature, the relationship between the VG voltage value and the temperature may be a linear relationship according to the experimental data, that is, the relationship between the VG voltage value and the temperature may be y = ax + b, and a and b are calculated according to the recorded VG voltage value at a low temperature, the VG voltage value at a normal temperature, and the VG voltage value at a high temperature, thereby obtaining a relationship between the VG voltage value and the temperature, and storing the relationship between the VG voltage value and the temperature in the first register of the MCU.

After a relation between the VG voltage value and the temperature is obtained, when the environment temperature of the optical module changes, the current temperature is collected through the temperature sensor, the theoretical VG voltage value under the current temperature can be obtained according to the relation, the MCU can adjust the output electric signal according to the theoretical VG voltage value so as to change the VG voltage input by the modulation driver, the modulation driver changes the driving voltage according to the adjusted VG voltage, and the coherent light assembly changes the emitting light power of the optical signal under the action of the adjusted driving voltage.

In some embodiments, the emitted optical power of the optical signal emitted by the coherent optical component is positively correlated with the driving voltage output by the modulation driver, and the driving voltage is positively correlated with the VG voltage, that is, when the VG voltage increases, the driving voltage increases and the emitted optical power of the optical signal increases; when the VG voltage decreases, the driving voltage decreases, and the emitted light power of the optical signal decreases.

However, the coherent optical module requires that the emitted light power of the optical signal is kept consistent, that is, the emitted light power of the optical signal is a fixed preset emitted light power, and when the temperature changes, the voltage value of VG changes, which causes the emitted light power of the optical signal to change.

Because the driving voltage output by the modulation driver is positively correlated with the actual emitted light power of the optical signal, the driving voltage output by the modulation driver can be monitored, and the change condition of the actual emitted light power can be known according to the driving voltage.

In order to monitor the actual driving voltage output by the modulation driver, the optical module provided in the embodiment of the present application further includes a voltage monitor, where the voltage monitor is electrically connected to the modulation driver and the MCU, and is configured to monitor the actual driving voltage output by the modulation driver, obtain a PKD voltage according to the actual driving voltage, and send the PKD voltage to the MCU. The PKD voltage is associated with an emitted optical power of the coherent optical module, and has a corresponding voltage value when the emitted optical power of the coherent optical module is fixed. For example, when the emitted optical power of the coherent optical module is 10dBm, the corresponding target PKD voltage is 2V.

The PKD voltage is also correlated with the VG voltage, and the PKD voltage is positively correlated with the VG voltage, that is, when the VG voltage increases, the driving voltage increases, and the PKD voltage increases; when the VG voltage decreases, the driving voltage decreases, and the PKD voltage decreases. Therefore, the voltage of the VG can be adjusted to adjust the voltage of the PKD, and the emitted light power of the coherent light module can be adjusted by adjusting the voltage of the PKD.

In some embodiments, the VG voltage and the PKD voltage do not correspond to each other, that is, when the VG voltage is 1V, the corresponding PKD voltage may be 2V; the voltage VG is 1.1V, and the corresponding PKD voltage may be 2V. Thus, the VG voltage and the PKD voltage are in a positive correlation, but the correspondence between the VG voltage and the PKD voltage is not determined, and the actual PKD voltage corresponding to the VG voltage can only be obtained by the voltage monitor.

When the temperature changes, the temperature sensor collects the current temperature, the MCU obtains a target VG voltage under the current temperature according to a relation table of the VG voltage and the temperature, the MCU adjusts an output electric signal according to the target VG voltage, the digital-to-analog converter adjusts the voltage of VG provided for the modulation driver according to the adjusted electric signal, the modulation driver outputs an adjusted driving voltage according to the adjusted VG voltage, and the coherent light component changes the emitting light power of the optical signal under the action of the adjusted driving voltage; the driving voltage output by the modulation driver is obtained through monitoring of the voltage monitor, the voltage monitor obtains the PKD voltage according to the driving voltage, and the PKD voltage is sent to the MCU.

In some embodiments, the MCU further includes a second register storing a target PKD voltage corresponding to a preset emitted optical power, for example, when the emitted optical power of the coherent light module is 10dBm, the target PKD voltage stored in the second register is 2V.

The MCU also comprises a comparator, the comparator is connected with the second register and the voltage monitor, and the comparator is used for comparing the PKD voltage fed back by the voltage monitor with the target PKD voltage and outputting a PKD voltage difference. Namely, when the emitting light power of the coherent light module is fixed, if the preset emitting light power of the coherent light module is 10dBm, the comparator compares the collected actual PKD voltage value with the target PKD voltage value (2V) to determine whether the emitting light power under the current VG value reaches the preset emitting light power.

The controller of the MCU receives the PKD voltage difference output by the comparator, adjusts the electric signal output by the MCU according to the PKD voltage difference, and further adjusts the VG voltage input by the modulation driver and the output driving voltage, so that the actual PKD voltage corresponding to the driving voltage is adjusted by adjusting the VG voltage until the actual PKD voltage is the same as the target PKD voltage.

For example, when the difference between the PKD voltages output by the comparator is less than zero, that is, the actual PKD voltage is less than the target PKD voltage, the control unit increases the electrical signal output by the MCU to increase the VG voltage input by the modulation driver and the output driving voltage, so that the actual PKD voltage increases until the actual PKD voltage is the same as the target PKD voltage; when the voltage difference of the PKD output by the comparator is greater than zero, namely the actual PKD voltage is greater than the target PKD voltage, the electric signal output by the MCU is controlled to be reduced so as to reduce the VG voltage input by the modulation driver and the output driving voltage, and the actual PKD voltage is reduced until the actual PKD voltage is the same as the target PKD voltage.

In some embodiments, the preset emitted optical power of the coherent optical module is required to be stabilized at 10dBm, and the target PKD voltage corresponding to the preset emitted optical power is 2V. The temperature of a coherent light component of the optical module at the previous moment is 20 ℃, and the VG voltage of a modulation driver at the temperature of 20 ℃ is 1V; and then after the temperature of the optical module is changed, the current temperature is 15 ℃, the theoretical VG voltage at the temperature of 15 ℃ is calculated and obtained to be 1.5V according to a relation table of the VG voltage and the temperature, the MCU adjusts the output electric signal according to the obtained theoretical VG voltage, so that the VG voltage output by the modulation driver is 1.5V, the driving voltage output by the modulation driver is increased, the actual PKD voltage obtained by the voltage monitor may not be equal to 2V, the actual PKD voltage is different from the target PKD voltage, and at the moment, the MCU controls and adjusts the output electric signal according to the PKD voltage difference between the actual PKD voltage and the target PKD voltage, so as to adjust the VG voltage input by the modulation driver and the output driving voltage again, then the actual PKD voltage corresponding to the adjusted driving voltage is obtained, and the actual PKD voltage is compared with the target PKD voltage.

If the regulated actual PKD voltage is still not the same as the target PKD voltage, the VG voltage input by the modulation driver is continuously regulated until the regulated VG voltage corresponds to the driving voltage, and the actual PKD voltage corresponding to the driving voltage is the same as the target PKD voltage. Therefore, after adjustment, the emitted light power of the coherent light module before and after temperature change is the same.

The optical module provided by the embodiment of the application comprises a circuit board, a laser, an MCU, a digital-to-analog converter, a modulation driver, a coherent optical component and a voltage monitor, wherein the laser is electrically connected with the circuit board and used for outputting light; the MCU comprises a temperature sensor, the temperature sensor is used for collecting the current temperature, and the MCU adjusts the output electric signal when the temperature changes; the digital-to-analog converter is electrically connected with the MCU, receives the electric signal sent by the MCU and outputs VG voltage; the modulation driver is electrically connected with the digital-to-analog converter, receives VG voltage provided by the digital-to-analog converter, processes the VG voltage and then outputs driving voltage, and the driving voltage is related to the VG voltage; the coherent light component is electrically connected with the modulation driver, is connected with the laser, and receives the light output by the laser and the driving voltage provided by the modulation driver so as to change the emitted light power of the optical signal under the action of the driving voltage; the voltage monitor is electrically connected with the modulation driver and the MCU and is used for monitoring the driving voltage output by the modulation driver, obtaining the PKD voltage according to the driving voltage and feeding back the PKD voltage to the MCU. Therefore, when the temperature changes, the temperature sensor collects the current temperature, the MCU obtains a target VG voltage under the current temperature according to a relation table of the VG voltage and the temperature, the MCU adjusts an output electric signal according to the target VG voltage, the digital-to-analog converter adjusts the voltage of VG provided for the modulation driver according to the adjusted electric signal, the modulation driver outputs an adjusted driving voltage according to the adjusted VG voltage, and the coherent light component changes the emission light power of the optical signal under the action of the adjusted driving voltage; monitoring and obtaining a driving voltage output by the modulation driver through a voltage monitor, obtaining a PKD voltage according to the driving voltage by the voltage monitor, and sending the PKD voltage to the MCU; the MCU compares the PKD voltage fed back by the voltage monitor with a stored target PKD voltage and outputs a PKD voltage difference; the MCU adjusts the electric signal output by the MCU according to the PKD voltage difference, and further adjusts the VG voltage input by the modulation driver and the output driving voltage, so that the actual PKD voltage corresponding to the driving voltage is adjusted by adjusting the VG voltage until the actual PKD voltage is the same as the target PKD voltage.

When the temperature of the optical module changes, the MCU adjusts the output electric signal according to the feedback PKD voltage and the stored target PKD voltage so as to adjust the VG voltage input by the modulation driver and the output driving voltage and change the emitted light power of the optical signal until the actual PKD voltage corresponding to the adjusted driving voltage is the same as the target PKD voltage, so that the light emitting power of the coherent optical module is kept consistent at different temperatures.

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

Claims (9)

1. A light module, comprising:

a circuit board;

the laser is electrically connected with the circuit board and used for outputting light;

the MCU is electrically connected with the circuit board and comprises a temperature sensor, and the temperature sensor is used for acquiring the current temperature; the PKD voltage is used for receiving feedback, and the output electric signal is adjusted through the feedback PKD voltage when the temperature changes;

the digital-to-analog converter is electrically connected with the MCU and used for receiving the electric signal and outputting VG voltage;

the modulation driver is electrically connected with the digital-to-analog converter and used for receiving the VG voltage and outputting a driving voltage;

the coherent light component is electrically connected with the modulation driver, is connected with the laser, and is used for receiving the light and the driving voltage and changing the emitted light power of the optical signal under the action of the driving voltage;

and the voltage monitor is electrically connected with the modulation driver and the MCU and used for monitoring the driving voltage and feeding the PKD voltage back to the MCU.

2. The optical module according to claim 1, wherein the MCU further comprises a first register storing a relationship table of VG voltage and temperature, and the MCU outputs an electrical signal corresponding to the VG voltage at a current temperature when the temperature changes.

3. The optical module according to claim 2, wherein the relationship table of VG voltage and temperature includes a VG voltage value at a low temperature, a VG voltage value at a normal temperature, and a VG voltage value at a high temperature, the VG voltage value at the low temperature is greater than the VG voltage value at the normal temperature, and the VG voltage value at the normal temperature is greater than the VG voltage value at the high temperature.

4. The optical module of claim 3, wherein the VG voltage versus temperature table is linear.

5. The light module of claim 1, wherein the MCU further comprises a second register storing a target PKD voltage corresponding to the emitted optical power.

6. The light module of claim 5, wherein the MCU further comprises a comparator connected to the second register and the voltage monitor, the comparator is configured to compare the fed-back PKD voltage with the target PKD voltage and output a PKD voltage difference.

7. The light module of claim 6, wherein the MCU further comprises a controller, the controller is connected to the comparator, and the controller is configured to receive the PKD voltage difference and adjust the output current.

8. The optical module of claim 7, wherein the controller is configured to reduce the magnitude of the output current and control to reduce the voltage of VG when the PKD voltage difference is greater than zero; and when the PKD voltage difference is less than zero, increasing the output current and controlling to increase the VG voltage.

9. The optical module according to claim 1, wherein the VG voltage is in a positive correlation with the driving voltage, and the driving voltage is in a positive correlation with the PKD voltage.

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