Optical module

Abstract

The optical module provided by the invention comprises a light source, an optical modulation chip, a first optical power detection assembly, a second optical power detection assembly and an MCU, the optical modulation chip comprises an optical modulator, and the optical modulator modulates light which is emitted by the light source and does not carry data into an optical signal; the light modulator comprises two interference arms on which heaters are arranged, and at least one interference arm is provided with a phase shifter; the first optical power detection assembly and the second optical power detection assembly obtain first sampling voltage and second sampling voltage according to optical signals output by the two interference arms; the MCU is configured to receive the first sampling voltage and the second sampling voltage, and when the first sampling voltage and the second sampling voltage are not equal to a preset voltage, the MCU adjusts the driving voltage output to the phase shifter so as to roughly adjust the first sampling voltage and the second sampling voltage; driving voltage output to the heater is adjusted, and the adjusting voltage of the heater is smaller than the adjusting voltage of the phase shifter, so that the first sampling voltage and the second sampling voltage are finely adjusted. The optical power of the optical modulator is jointly adjusted through the phase shifter and the heater, and the power consumption of the optical module is reduced.

Description

Technical Field

[0001] The present disclosure relates to the field of optical communication technology, and in particular to an optical module. Background Art

[0002] With the development of new services and application models such as cloud computing, mobile Internet, and video, the advancement of optical communication technology has become increasingly important. In optical communication technology, optical modules, as one of the key components in optical communication equipment, can realize the conversion of optical and electrical signals. In the development of optical communication technology, the data transmission rate of optical modules is required to be continuously improved.

[0003] Some optical modules include optical modulation chips, in which Mach-Zehnder Modulator (MZM) is integrated. As a key component of optical communication links, MZM modulators are mainly used to modulate radio frequency communication signals onto optical carriers, so their modulation performance has a great impact on the performance of optical communication links. MZM modulators should work at the optimal operating point, where the optimal operating point is a phase difference of π / 2. The output signal effect of the MZM modulator working at the optimal operating point is better than the output signal effect working at a non-optimal operating point.

[0004] However, with the influence of a series of external conditions such as time, ambient temperature, laser optical power, fiber insertion and coupling loss, the optimal working point of the MZM modulator will drift, resulting in adverse effects such as poor signal quality of optical module transmission and increased bit error rate. Summary of the invention

[0005] The present disclosure provides an optical module to ensure that an MZM modulator is always at an optimal working point.

[0006] The optical module provided by the present disclosure includes:

[0007] Circuit boards;

[0008] A light source, electrically connected to the circuit board, and configured to emit direct current light that does not carry data;

[0009] an optical modulation chip, electrically connected to the circuit board, the optical modulation chip comprising an optical modulator, the optical modulator being used to modulate the direct current light not carrying data into an optical signal; wherein the optical modulator comprises two interference arms, heaters are provided on the two interference arms, and a phase shifter is provided on at least one of the interference arms, the phase shifter and the heater being used to change the refractive index of the interference arm;

[0010] A first optical power detection component is provided at one side of the interference arm, and the first optical power detection component is used to obtain a first sampling voltage according to the optical signal output by the interference arm;

[0011] A second optical power detection component is disposed on one side of the other interference arm, and the second optical power detection component is used to obtain a second sampling voltage according to the optical signal output by the interference arm;

[0012] An MCU is electrically connected to the circuit board. The MCU outputs driving voltages to the phase shifter and the heater respectively. The MCU is configured to receive the first sampling voltage and the second sampling voltage, and when the first sampling voltage and the second sampling voltage are not equal to a preset voltage, adjust the driving voltage output to the phase shifter to coarsely adjust the first sampling voltage and / or the second sampling voltage; and adjust the driving voltage output to the heater, wherein the adjustment voltage of the heater is less than the adjustment voltage of the phase shifter, so as to finely adjust the first sampling voltage and the second sampling voltage, so as to adjust the first sampling voltage and the second sampling voltage to the preset voltage.

[0013] The optical module provided by the present invention includes a circuit board, a power supply, an optical modulation chip, a first optical power detection component, a second optical power detection component and an MCU, a light source is electrically connected to the circuit board, the light source is used to emit light that does not carry data to output light to the optical modulation chip; the optical modulation chip is electrically connected to the circuit board, the optical modulation chip includes an optical modulator, the optical modulator is used to modulate the light that does not carry data into an optical signal, wherein the optical modulator includes two interference arms, the two interference arms are provided with heaters, the heater can heat or cool the interference arms under the action of a driving voltage to change the refractive index of the interference arm; at least one interference arm is provided with a phase shifter, the phase shifter can change the refractive index of the interference arm under the driving voltage, so that the phase shifter and the heater jointly control the refractive index of the interference arm; the first optical power detection component is arranged on one side of an interference arm, the first optical power detection component is used to obtain a first sampling voltage according to the optical signal output by the interference arm, so as to detect the optical power of the optical signal output by the interference arm; the second The optical power detection component is arranged on one side of the other interference arm, and the second optical power detection component is used to obtain a second sampling voltage according to the optical signal output by the interference arm to detect the optical power of the optical signal output by the interference arm; the MCU is electrically connected to the circuit board, and the MCU outputs driving voltages to the phase shifter and the heater respectively. The MCU is configured to receive the first sampling voltage and the second sampling voltage, and when the first sampling voltage and the second sampling voltage are not equal to the preset voltage, adjust the driving voltage output to the phase shifter, change the phase difference of the optical signals output by the two interference arms, so as to roughly adjust the first sampling voltage and / or the second sampling voltage; then adjust the driving voltage output to the heater, the adjustment voltage of the heater is less than the adjustment voltage of the phase shifter, and further change the phase difference of the optical signals output by the two interference arms to finely adjust the first sampling voltage and the second sampling voltage, so as to adjust the first sampling voltage and the second sampling voltage to the preset voltage, thereby locking the working point of the optical modulator at the optimal working point.

[0014] The present invention adds a phase shifter to the two interference arms of the optical modulator, and roughly adjusts the phase difference of the optical signals output by the two interference arms by controlling the voltage value loaded to the phase shifter. The load of the phase shifter is very small, and basically no additional current is generated, and no additional power consumption is generated. Then, the phase difference of the optical signals output by the two interference arms is finely adjusted by controlling the voltage value loaded to the heater, which can reduce the driving voltage loaded to the heater and the current injected into the heater, thereby reducing the power consumption of the optical module and improving the signal quality transmitted by the optical module. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the present disclosure, the following briefly introduces the drawings used in some embodiments of the present disclosure. Obviously, the drawings described below are only drawings of some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can also be obtained based on these drawings. In addition, the drawings described below can be regarded as schematic diagrams, and are not limitations on the actual size of the product involved in the embodiments of the present disclosure, the actual process of the method, the actual timing of the signal, etc.

[0016] Figure 1 A partial structural diagram of an optical communication system provided according to some embodiments of the present disclosure;

[0017] Figure 2 A partial structural diagram of a host computer provided according to some embodiments of the present disclosure;

[0018] Figure 3 A structural diagram of an optical module provided according to some embodiments of the present disclosure;

[0019] Figure 4 An exploded view of an optical module provided according to some embodiments of the present disclosure;

[0020] Figure 5 An internal structure diagram of an optical module provided according to some embodiments of the present disclosure;

[0021] Figure 6 A structure of an electro-optic modulator in an optical module provided according to some embodiments of the present disclosure Figure 1 ;

[0022] Figure 7 A signal diagram of an electro-optic modulator in an optical module provided according to some embodiments of the present disclosure;

[0023] Figure 8 A structure of an electro-optic modulator in an optical module provided according to some embodiments of the present disclosure Figure 2 ;

[0024] Fig. 9A structural diagram of a first optical power detection component in an optical module provided according to some embodiments of the present disclosure;

[0025] Fig.10 A structure of an electro-optic modulator in an optical module provided according to some embodiments of the present disclosure Figure 3 . DETAILED DESCRIPTION

[0026] In optical communication technology, in order to establish information transmission between information processing devices, it is necessary to load information onto light and use the propagation of light to achieve information transmission. Here, the light loaded with information is an optical signal. When optical signals are transmitted in information transmission equipment, the loss of optical power can be reduced, so high-speed, long-distance, and low-cost information transmission can be achieved. The signals that information processing equipment can recognize and process are electrical signals. Information processing equipment usually includes optical network terminals (Optical Network Unit, ONU), gateways, routers, switches, mobile phones, computers, servers, tablets, televisions, etc., and information transmission equipment usually includes optical fibers and optical waveguides.

[0027] The optical module can realize the mutual conversion between optical signals and electrical signals between information processing equipment and information transmission equipment. For example, at least one of the optical signal input end or the optical signal output end of the optical module is connected to an optical fiber, and at least one of the electrical signal input end or the electrical signal output end of the optical module is connected to an optical network terminal; the first optical signal from the optical fiber is transmitted to the optical module, and the optical module converts the first optical signal into a first electrical signal, and transmits the first electrical signal to the optical network terminal; the second electrical signal from the optical network terminal is transmitted to the optical module, and the optical module converts the second electrical signal into a second optical signal, and transmits the second optical signal to the optical fiber. Since multiple information processing devices can transmit information through electrical signals, at least one of the multiple information processing devices needs to be directly connected to the optical module, and all information processing devices do not need to be directly connected to the optical module. Here, the information processing device directly connected to the optical module is called the upper computer of the optical module. In addition, the optical signal input end or the optical signal output end of the optical module can be called an optical port, and the electrical signal input end or the electrical signal output end of the optical module can be called an electrical port.

[0028] Figure 1 FIG. 1 is a partial structural diagram of an optical communication system provided according to some embodiments of the present disclosure. Figure 1 As shown, the optical communication system mainly includes a remote information processing device 1000 , a local information processing device 2000 , a host computer 100 , an optical module 200 , an optical fiber 101 and a network cable 103 .

[0029] One end of the optical fiber 101 extends toward the remote information processing device 1000, and the other end of the optical fiber 101 is connected to the optical module 200 through the optical port of the optical module 200. The optical signal can be totally reflected in the optical fiber 101, and the propagation of the optical signal in the total reflection direction can almost maintain the original optical power. The optical signal undergoes multiple total reflections in the optical fiber 101 to transmit the optical signal from the remote information processing device 1000 to the optical module 200, or to transmit the optical signal from the optical module 200 to the remote information processing device 1000, thereby realizing long-distance, low-power loss information transmission.

[0030] The optical communication system may include one or more optical fibers 101, and the optical fibers 101 are detachably connected or fixedly connected to the optical module 200. The host computer 100 is configured to provide data signals to the optical module 200, receive data signals from the optical module 200, or monitor or control the working state of the optical module 200.

[0031] The host computer 100 includes a substantially rectangular housing and an optical module interface 102 disposed on the housing. The optical module interface 102 is configured to connect to the optical module 200 so that the host computer 100 and the optical module 200 establish a unidirectional or bidirectional electrical signal connection.

[0032] The host computer 100 also includes an external electrical interface, which can be connected to an electrical signal network. For example, the external electrical interface includes a Universal Serial Bus (USB) interface or a network cable interface 104, and the network cable interface 104 is configured to access the network cable 103 so that the host computer 100 establishes a unidirectional or bidirectional electrical signal connection with the network cable 103. One end of the network cable 103 is connected to the local information processing device 2000, and the other end of the network cable 103 is connected to the host computer 100, so as to establish an electrical signal connection between the local information processing device 2000 and the host computer 100 through the network cable 103. For example, the third electrical signal sent by the local information processing device 2000 is transmitted to the host computer 100 through the network cable 103, and the host computer 100 generates a second electrical signal according to the third electrical signal. The second electrical signal from the host computer 100 is transmitted to the optical module 200, and the optical module 200 converts the second electrical signal into a second optical signal, and transmits the second optical signal to the optical fiber 101, and the second optical signal is transmitted to the remote information processing device 1000 in the optical fiber 101. For example, the first optical signal from the remote information processing device 1000 is transmitted through the optical fiber 101, and the first optical signal from the optical fiber 101 is transmitted to the optical module 200, and the optical module 200 converts the first optical signal into a first electrical signal, and the optical module 200 transmits the first electrical signal to the host computer 100, and the host computer 100 generates a fourth electrical signal according to the first electrical signal, and transmits the fourth electrical signal to the local information processing device 2000. It should be noted that the optical module is a tool for realizing the mutual conversion between optical signals and electrical signals. During the conversion process between the optical signals and electrical signals, the information does not change, but the encoding and decoding methods of the information can change.

[0033] In addition to the optical network terminal, the host computer 100 also includes an optical line terminal (OLT), an optical network device (ONT), or a data center server.

[0034] Figure 2 1 is a partial structural diagram of a host computer provided according to some embodiments of the present disclosure. In order to clearly show the connection relationship between the optical module 200 and the host computer 100, Figure 2 Only the structure of the host computer 100 related to the optical module 200 is shown. Figure 2 As shown, the host computer 100 further includes a PCB circuit board 105 disposed in the housing, a cage 106 disposed on the surface of the PCB 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 the electrical port of the optical module 200; the heat sink 107 has a protruding structure such as fins to increase the heat dissipation area.

[0035] The optical module 200 is inserted into the cage 106 of the host computer 100, and the cage 106 fixes the optical module 200. The heat generated by the optical module 200 is transferred to the cage 106 and then diffused through the 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 establishes a bidirectional electrical signal connection with the host computer 100. In addition, the optical port of the optical module 200 is connected to the optical fiber 101, so that the optical module 200 establishes a bidirectional optical signal connection with the optical fiber 101.

[0036] Figure 3 is a structural diagram of an optical module provided according to some embodiments of the present disclosure, Figure 4 FIG. 1 is an exploded view of an optical module provided according to some embodiments of the present disclosure. Figure 3 and Figure 4 As shown, the optical module 200 includes a shell, a circuit board 300 disposed in the shell, an optical modulation chip 900a, a light source 900b, etc., but the present disclosure is not limited thereto.

[0037] The housing comprises an upper housing 201 and a lower housing 202 . The upper housing 201 covers the lower housing 202 to form the housing having two openings 204 and 205 . The outer contour of the housing is generally a square body.

[0038] In some embodiments, the lower shell 202 includes a bottom plate 2021 and two lower side plates 2022 located on both sides of the bottom plate 2021 and arranged perpendicular to the bottom plate 2021; the upper shell 201 includes a cover plate 2011, and the cover plate 2011 covers the two lower side plates 2022 of the lower shell 202 to form the above-mentioned shell.

[0039] In some embodiments, the lower shell 202 includes a bottom plate 2021 and two lower side plates 2022 located on both sides of the bottom plate 2021 and vertically arranged with the bottom plate 2021; the upper shell 201 includes a cover plate 2011 and two upper side plates located on both sides of the cover plate 2011 and vertically arranged with the cover plate 2011, and the two upper side plates are combined with the two lower side plates 2022 to realize that the upper shell 201 covers the lower shell 202.

[0040] The direction of the line connecting the two openings 204 and 205 may be consistent with the length direction of the optical module 200, or may be inconsistent with the length direction of the optical module 200. For example, the opening 204 is located at the end of the optical module 200 ( Figure 3 The opening 205 is also located at the end of the optical module 200 ( Figure 3Alternatively, the opening 204 is located at the end of the optical module 200, and the opening 205 is located at the side of the optical module 200. The opening 204 is an electrical port, and the gold finger 301 of the circuit board 300 extends from the electrical port and is inserted into the electrical connector of the host computer 100; the opening 205 is an optical port, which is configured to access the external optical fiber 101, so that the optical fiber 101 is connected to the optical modulation chip 900a and the light source 900b in the optical module 200.

[0041] The upper housing 201 and the lower housing 202 are combined to facilitate installation of the circuit board 300, the optical modulation chip 900a, the light source 900b, etc. into the housing, and the upper housing 201 and the lower housing 202 can encapsulate and protect the above components. In addition, when assembling the circuit board 300, the optical modulation chip 900a, the light source 900b, etc., the upper housing 201 and the lower housing 202 are combined to facilitate the deployment of the positioning components, heat dissipation components, and electromagnetic shielding components of these components, which is conducive to automated production.

[0042] In some embodiments, the upper shell 201 and the lower shell 202 are made of metal materials to facilitate electromagnetic shielding and heat dissipation.

[0043] In some embodiments, the optical module 200 further includes an unlocking component 600 located outside its housing. The unlocking component 600 is configured to achieve a fixed connection between the optical module 200 and the host computer, or to release the fixed connection between the optical module 200 and the host computer.

[0044] For example, the unlocking component 600 is located on the outside of the two lower side plates 2022 of the lower housing 202, and includes a snap-fit ​​component that matches the cage 106 of the host computer 100. When the optical module 200 is inserted into the cage 106, the snap-fit ​​component of the unlocking component 600 fixes the optical module 200 in the cage 106; when the unlocking component 600 is pulled, the snap-fit ​​component of the unlocking component 600 moves accordingly, thereby changing the connection relationship between the snap-fit ​​component and the host computer, so as to release the fixation of the optical module 200 and the host computer, so that the optical module 200 can be pulled out of the cage 106.

[0045] The circuit board 300 includes circuit traces, electronic components and chips, etc. The electronic components and chips are connected according to the circuit design through the circuit traces to realize the functions of power supply, electrical signal transmission and grounding. The electronic components may include capacitors, resistors, transistors, metal-oxide-semiconductor field-effect transistors (Metal-Oxide-Semiconductor Field-Effect Transistor, MOSFET), etc. The chips may include microcontroller units (Microcontroller Unit, MCU), laser driver chips, transimpedance amplifiers (Transimpedance Amplifier, TIA), limiting amplifiers (Limiting amplifier), clock and data recovery chips (Clock and Data Recovery, CDR), power management chips, digital signal processing (Digital Signal Processing, DSP) chips.

[0046] The circuit board 300 is generally a rigid circuit board. Due to its relatively hard material, the rigid circuit board can also realize the load-bearing function. For example, the rigid circuit board can stably carry the above-mentioned electronic components and chips; the rigid circuit board can also be inserted into the electrical connector in the cage 106 of the host computer 100.

[0047] The circuit board 300 also includes a gold finger 301 formed on the end surface thereof. The gold finger 301 is composed of a plurality of independent pins. The circuit board 300 is inserted into the cage 106, and the gold finger 301 is connected to the electrical connector in the cage 106. The gold finger 301 can be provided on only one side of the circuit board 300 (e.g. Figure 4 The upper surface shown in the figure) can also be set on the upper and lower surfaces of the circuit board 300 to provide more pins, so as to adapt to occasions where the number of pins is large. The gold finger 301 is configured to establish an electrical connection with the host computer to achieve power supply, grounding, two-wire synchronous serial (Inter-Integrated Circuit, I2C) signal transmission, data signal transmission, etc. Of course, flexible circuit boards are also used in some optical modules. Flexible circuit boards are generally used in conjunction with rigid circuit boards to supplement rigid circuit boards.

[0048] Figure 5 FIG. 1 is an internal structure diagram of an optical module provided according to some embodiments of the present disclosure. Figure 5As shown, the optical modulation chip 900a does not have a light source itself, so the light source 900b is selected as the external light source of the optical modulation chip 900a. The light source 900b can be a laser box. The laser box has a laser chip encapsulated inside. The laser chip emits light to generate a laser beam. The light source 900b is used to provide the emission laser to the optical modulation chip 900a. The laser has a good single wavelength characteristic and a better wavelength tuning characteristic. It has become the preferred light source for optical modules and even optical fiber transmission. Other types of light, such as LED light, are generally not used in common optical communication systems. Even if such a light source is used in a special optical communication system, the characteristics of the light source and the chip components are greatly different from those of the laser, which makes the optical module using lasers and the optical module using other light sources have great technical differences. Those skilled in the art generally do not think that these two types of optical modules can give technical inspiration to each other.

[0049] The bottom surface of the optical modulator chip 900a and the bottom surface of the light source 900b are respectively arranged on the substrate. There is an optical connection between the optical modulator chip 900a and the light source 900b. The optical path is very sensitive to the positional relationship between the optical modulator chip and the light source. Materials with different expansion coefficients lead to different degrees of formation, which is not conducive to the realization of the preset optical path.

[0050] In the embodiment of the present disclosure, the light modulation chip 900a and the light source 900b are arranged on the same substrate. The deformation of the substrate made of the same material will equally affect the positions of the light modulation chip 900a and the light source 900b, and avoid a large change in the relative positions of the light modulation chip 900a and the light source 900b. In some embodiments, it is preferred that the expansion coefficient of the substrate material is close to the expansion coefficient of the light modulation chip 900a and / or the light source 900b material.

[0051] In some embodiments, the optical modulation chip 900a may be formed as a silicon photonic chip or a thin-film lithium niobate chip, etc. Exemplarily, the optical modulation chip 900a is a thin-film lithium niobate chip. The thin-film lithium niobate chip includes a substrate and an optical modulation thin film layer located on the surface of the substrate, the optical modulation thin film layer has an input optical waveguide, a Mach Zehnder modulator (MZM modulator) and an output optical waveguide, the substrate is a glass substrate, the optical modulation thin film layer may be a lithium niobate thin film, the lithium niobate thin film is laid on the substrate, and the thickness of the lithium niobate thin film is less than 100 μm.

[0052] Thin-film lithium niobate chips are relatively small in size and have relatively high integration precision. Compared with silicon photonic chips, thin-film lithium niobate chips have the advantages of low power consumption and low optical loss. Among them, the optical loss of silicon photonic chips is less than 11.2dB, and the optical loss of thin-film lithium niobate chips is less than 10dB.

[0053] The light source 900b provides light to the optical modulation chip 900a, such as a thin-film lithium niobate chip, as emitted light with a single wavelength and stable power, which does not carry any signal. The thin-film lithium niobate chip modulates the emitted light to load data into the emitted light to obtain a modulated light signal.

[0054] In some embodiments, the light modulation chip 900a, such as a thin-film lithium niobate chip, receives the emitted light from the light source 900b on its side, and the modulation of the emitted light is completed by the thin-film lithium niobate chip, and the surface of the thin-film lithium niobate chip is provided with a pad that is electrically connected to the circuit board 300. In this way, the circuit board 300 provides the thin-film lithium niobate chip with a data signal from the host computer, and the thin-film lithium niobate chip modulates the data signal into the emitted light to obtain a modulated light signal, and the modulated light signal is transmitted to the host computer.

[0055] Figure 6 A structure of an electro-optic modulator in an optical module provided according to some embodiments of the present disclosure Figure 1 , Figure 7 FIG. 1 is a signal diagram of an electro-optic modulator in an optical module according to some embodiments of the present disclosure. Figure 6 and Figure 7 As shown, the optical modulation chip 900a, such as a thin film lithium niobate chip, includes an optical modulator, which can be a Mach Zehnder Modulator (MZM). The incident light enters the MZM modulator, and after a certain distance, the incident light is divided into two beams of light with completely equal amplitude and frequency at the first Y branch. The two beams of light pass through two branches of the optical waveguide respectively, and converge at the second Y branch for interference output.

[0056] In the MZM modulator, the lithium niobate optical waveguide undergoes electro-optic effect under the action of electrode voltage, forming electro-optic modulation. Since the two electrodes (upper arm modulation electrode Mu and lower arm modulation electrode Md) are symmetrical structures, the voltages induced in the two arms of the MZM modulator are equal in magnitude and opposite in direction, so the phase shifts of the two branch light waves induced are equal in magnitude and opposite in direction.

[0057] When the phase difference generated by electro-optic modulation is 0 or π, the optical carrier signal will achieve coherent constructive or coherent destructive phase, thereby completing the modulation of the optical carrier signal. When the phase difference generated by electro-optic modulation is π / 2, the relative output light intensity of the electro-optic modulator is linearly related to the electrode voltage. At this time, the dynamic range and conversion efficiency of the output signal are both maximum. Therefore, it is necessary to add an appropriate DC component to the electrode voltage to ensure the establishment of an appropriate working point. When the DC component forms a phase difference of π / 2 for the two light waves, the linearity is the highest and linear modulation can be achieved. That is, an external DC bias voltage is required to stabilize the working point at a phase difference of π / 2.

[0058] Ideally, the MZM modulator can work stably at this working point. However, with the influence of a series of external conditions such as time, ambient temperature, laser optical power, fiber insertion and coupling loss, the optimal working point of the MZM modulator will drift, resulting in adverse effects such as poor signal quality and increased bit error rate. In order to ensure that the optimal working point is in a stable state for a long time, we need to increase compensation for the drift of the optimal working point.

[0059] When solving the problem of the optimal operating point of the MZM modulator drifting due to a series of external conditions such as time, ambient temperature, laser emission light power, fiber insertion and coupling loss, a PD feedback compensation circuit can be built to ensure that the two-arm electrodes produce a constant phase difference, so that it can be stabilized at the optimal operating point for a long time.

[0060] Figure 8 A structure of an electro-optic modulator in an optical module provided according to some embodiments of the present disclosure Figure 2 .like Figure 8 As shown, the optical modulator includes a first beam splitter 901 , a first interference arm 902 , a second interference arm 903 and a combiner 906 .

[0061] One end of the first optical splitter 901 is connected to the light source 900b through an optical fiber. The first optical splitter 901 is used to split the emission light that does not carry a signal emitted by the light source 900b into two identical beams of light, that is, the first optical splitter 901 splits a beam of light signal that does not carry data into a first beam and a second beam. In some embodiments, the first optical splitter 901 can split a beam of light signal into two completely identical beams of light signals, or into two non-completely identical beams of light signals. In order to facilitate interference between the two beams of light signals, the first optical splitter 901 splits a beam of light signal into two completely identical beams of light signals.

[0062] One end of the first interference arm 902 and the second interference arm 903 are respectively connected to the first beam splitter 901, and the first interference arm 902 is used to transmit the first split light, and the second interference arm 903 is used to transmit the second split light. That is, the first interference arm 902 and the second interference arm 903 respectively transmit the two light signals separated by the first beam splitter 901, and the first interference arm 902 and the second interference arm 903 combine the two light signals into one light signal by using the principle of interference of light of the same wavelength.

[0063] A first modulation electrode is provided on the first interference arm 902. The first modulation electrode utilizes electro-optical induction to change the refractive index of the modulator material, converts the modulated electrical signal transmitted by the circuit board 300 into a modulated optical signal, and utilizes the modulated optical signal to convert the DC optical signal (i.e., the first split light) on the first interference arm 902 that does not carry data into a first alternating optical signal that carries data.

[0064] A second modulation electrode is provided on the second interference arm 903. The second modulation electrode changes the refractive index of the modulator material by utilizing electro-optical induction, converts the modulated electrical signal transmitted by the circuit board 300 into a modulated optical signal, and utilizes the modulated optical signal to convert the DC optical signal (i.e., the second split light) on the second interference arm 903 that does not carry data into a second alternating optical signal that carries data. The second alternating optical signal has a different phase from the first alternating optical signal.

[0065] In some embodiments, the first interference arm 902 and the second interference arm 903 are respectively provided with a first heater and a second heater, and the first heater and the second heater are used to control the phase difference of the alternating light signal transmitted on the first interference arm 902 and the second interference arm 903 to be constant according to the driving voltage sent by the MCU. That is, the first heater and the second heater are controlled to work according to the driving voltage sent by the MCU to increase or decrease the temperature of the first interference arm 902 and the second interference arm 903.

[0066] When the heater heats or cools the first interference arm 902 and the second interference arm 903, it can change the refractive index of the first interference arm 902 and the second interference arm 903, thereby changing the optical path difference of the two alternating light signals entering the first heater and the second heater, and then changing the phase difference of the two alternating light signals passing through the two heaters, so that the phase difference of the two alternating light signals passing through the two heaters is π / 2.

[0067] The second beam splitter 904 is disposed at one end of the first interferometer arm 902, and the second beam splitter 904 is used to split the alternating light signal on the first interferometer arm 902 into a beam of light signal with a smaller ratio and a beam of light signal with a larger ratio. That is, the second beam splitter 904 splits the alternating light signal on the first interferometer arm 902 into two beams of alternating light signals, the two beams of light signals being the first beam of alternating light signals and the second beam of alternating light signals, respectively. The first beam of alternating light signals is an alternating light signal with a smaller ratio, and the second beam of alternating light signals is an alternating light signal with a larger ratio. In some embodiments, the power ratio of the first beam of alternating light signals to the second beam of alternating light signals can be set to 2:98.

[0068] The third beam splitter 905 is disposed at one end of the second interferometer arm 903, and the third beam splitter 905 is used to split the alternating light signal on the second interferometer arm 903 into a beam of light signal with a smaller ratio and a beam of light signal with a larger ratio. That is, the third beam splitter 905 splits the alternating light signal on the second interferometer arm 903 into two beams of alternating light signals, the two beams of light signals are the third beam of alternating light signals and the fourth beam of alternating light signals, the third beam of alternating light signals is an alternating light signal with a smaller ratio, and the fourth beam of alternating light signals is an alternating light signal with a larger ratio. In some embodiments, the power ratio of the third beam of alternating light signals to the fourth beam of alternating light signals can be set to 2:98.

[0069] One end of the combiner 906 is respectively connected to one end of the second optical splitter 904 and the third optical splitter 905, and the combiner 906 is used to combine two large-scale alternating optical signals into one alternating optical signal. That is, the combiner 906 combines the large-scale second alternating optical signal and the fourth alternating optical signal into one alternating optical signal, and transmits the alternating optical signal to achieve the transmission of the alternating optical signal.

[0070] In some embodiments, the optical modulation chip 900a, such as a thin-film lithium niobate chip, includes an input optical port, an output optical port, a monitoring optical port, a high-speed electrical signal input interface, and a DC bias signal input interface. The input optical port is used to couple the light that does not carry data output by the light source 900b into the optical modulation chip 900a. The light input through the input optical port is divided into two beams of light of equal proportions by a first spectrometer 901.

[0071] The output optical port is connected to the combiner 906. After the combiner 906 combines the second alternating optical signal and the fourth alternating optical signal into one alternating optical signal, the alternating optical signal is emitted through the output optical port.

[0072] The monitoring optical port is connected to the second optical splitter 904 and the third optical splitter 905. The first beam of alternating optical signals separated by the second optical splitter 904 is transmitted to the first optical power detection component 920 via the monitoring optical port. The third beam of alternating optical signals separated by the third optical splitter 905 is transmitted to the second optical power detection component 930 via the monitoring optical port. The modulated optical signal is monitored by the first optical power detection component 920 and the second optical power detection component 930. The photodetector generates a photocurrent, which is collected by the sampling circuit and sent to the MCU for processing.

[0073] The high-speed electrical signal input interface is connected to the first modulation electrode and the second modulation electrode, and a high-speed electrical signal is input to the first modulation electrode and the second modulation electrode through the high-speed electrical signal input interface to perform optical modulation on the first interference arm 902 and the second interference arm 903 .

[0074] The DC bias signal input interface is connected to the MCU, the first heater and the second heater. The MCU inputs a DC bias voltage (current) signal to the DC bias signal input interface and applies the DC bias voltage (current) signal to the first heater and the second heater to control the optimal operating point of the MZM modulator.

[0075] Affected by the change in the working temperature of the modulator, the working point of the optical modulation chip 900a is prone to drift, so that the optical modulation chip 900a is not in the optimal working point state. Therefore, the working point of the optical modulation chip 900a needs to be locked at the optimal working point.

[0076] In some embodiments, the optical power of the optical modulation chip 900a can be detected by an optical power detector, so as to determine the working point state of the optical modulation chip 900a. Therefore, the optical module provided in the embodiment of the present disclosure also includes a first optical power detection component 920, a second optical power detection component 930 and an MCU, the first optical power detection component 920 and the second optical power detection component 930 are respectively connected to the optical modulation chip 900a patch, the first optical power detection component 920 is connected to one end of the second optical splitter 904, the first optical power detection component 920 is used to collect a second beam of alternating optical signals with a smaller proportion, and the first optical power detection component 920 converts the second beam of alternating optical signals into a voltage signal to obtain a corresponding first sampling voltage.

[0077] The second optical power detection component 930 is connected to one end of the third optical splitter 905 and is used to collect a third beam of alternating optical signals with a smaller proportion. The second optical power detection component 930 converts the third beam of alternating optical signals into a voltage signal to obtain a corresponding second sampling voltage.

[0078] Fig. 9 FIG. 1 is a structural diagram of a first optical power detection component in an optical module provided according to some embodiments of the present disclosure. Fig. 9 As shown, in some embodiments, the first optical power detection component 920 includes a first photodetector 921 and a first sampling resistor 922 , and the first photodetector 921 and the first sampling resistor 922 are electrically connected, and can be wired.

[0079] One end of the first photodetector 921 is electrically connected to an external power supply, and the first photodetector 921 is used to convert a light signal with a smaller proportion into a sampling current. One end of the first sampling resistor 922 is electrically connected to the first photodetector 921, and the other end of the first sampling resistor 922 is grounded. The first sampling resistor 922 is used to convert the sampling current into a sampling voltage, that is, the sampling current is divided by the first sampling resistor to obtain a first sampling voltage.

[0080] In some embodiments, the second optical power detection component 930 includes a second photodetector and a second sampling resistor, and the second photodetector and the second sampling resistor are electrically connected and can be wired.

[0081] One end of the second photodetector is electrically connected to the external power supply, and the second photodetector is used to convert the light signal with a smaller proportion into a sampling current. One end of the second sampling resistor is electrically connected to the second photodetector, and the other end of the second sampling resistor is grounded. The second sampling resistor is used to convert the sampling current into a sampling voltage, that is, the sampling current is divided by the second sampling resistor to obtain a second sampling voltage.

[0082] The MCU is electrically connected to the first optical power detection component 920 and the second optical power detection component 930 respectively, and can be connected by patch connection. The MCU is used to compare and analyze the first sampling voltage and the second sampling voltage, and judge whether the output driving voltage should be increased or decreased according to the comparison and analysis results, so as to control the voltage value loaded to the first heater and the second heater through the driving voltage, thereby forming different currents. The heater will produce a thermal effect due to the injection of current, thereby changing the refractive index of the interference arm, thereby changing the optical path difference between the first interference arm 902 and the second interference arm 903.

[0083] In some embodiments, changes in the driving voltage output by the MCU to the heater will affect the phase changes of the light signals output by the two interference arms, and the signal amplitude changes of the first photodetector 921 and the second photodetector, that is, affecting the first sampling voltage and the second sampling voltage, thereby forming a closed-loop feedback control loop. The entire loop will enable the dynamic stability of the MZM modulator to be between tiny voltage increases and decreases at the optimal operating point, thereby achieving automatic compensation for the DC bias of the MZM modulator at any time.

[0084] In some embodiments, the first heater on the first interference arm 902 and the second heater on the second interference arm 903 need to operate at 1.5V, and then adjust the driving voltage output by the MCU to the first heater and the second heater according to the change in the light power received by the first photodetector and the second photodetector, and the driving voltage can be increased or decreased.

[0085] During the whole process, it is necessary to ensure that the optical power received by the first photodetector and the second photodetector is equal. If the monitoring power of the photodetector becomes smaller, the heating current is reduced and the driving voltage is lowered; if the monitoring power of the photodetector becomes larger, the heating current is increased and the driving voltage is increased.

[0086] In some embodiments, the heater on the interference arm is a heating resistor, and the MCU controls the voltage value loaded to the heating resistor, thereby forming different currents. The heating resistor will produce a thermal effect due to the injection of current, thereby changing the refractive index of the interference arm. However, the refractive index of the interference arm is proportional to the current injected into the heating resistor. When the refractive index of the MZM modulator is changed by the heating resistor, additional power consumption will be generated.

[0087] Fig.10 A structure of an electro-optic modulator in an optical module provided according to some embodiments of the present disclosure Figure 3 .like Fig.10As shown, in order to reduce the additional power consumption caused by the heating resistor, a phase shifter is arranged on at least one interference arm, and the MCU sends a driving voltage to the phase shifter. The phase shifter can change the refractive index of the interference arm under the action of the driving voltage, so that the refractive index of the interference arm is jointly controlled by the phase shifter and the heater, and the adjustment voltage of the heater is smaller than the adjustment voltage of the phase shifter, so that the working point of the optical modulator is locked at the optimal working point under the action of a smaller heating current, thereby reducing the power consumption of the optical module.

[0088] The first interferometer arm 902 may be provided with a first phase shifter 907 and a first heater, and the second interferometer arm 903 may only be provided with a second heater. The first sampling voltage of the optical signal output by the first interferometer arm 902 is collected by the first optical power detection component 920, and the second sampling voltage of the optical signal output by the second interferometer arm 903 is collected by the second optical power detection component 930. The MCU compares and analyzes the first sampling voltage and the second sampling voltage to determine whether the driving voltage should be increased or decreased at present, and outputs it through the DAC to control the voltage value loaded to the first phase shifter 907, the first heater and the second heater, and the adjustment voltage of the first heater and the second heater is less than the adjustment voltage of the first phase shifter 907, so as to change the refractive index of the first interferometer arm 902 and the second interferometer arm 903, thereby changing the optical path difference between the two interferometer arms to ensure that the two interferometer arms produce a constant phase difference, so that the working point of the MZM modulator is locked at the optimal working point.

[0089] In some embodiments, only a first heater is provided on the first interferometer arm 902, and a second phase shifter 908 and a second heater are provided on the second interferometer arm 903. The first sampling voltage of the optical signal output by the first interferometer arm 902 is collected by the first optical power detection component 920, and the second sampling voltage of the optical signal output by the second interferometer arm 903 is collected by the second optical power detection component 930. The MCU compares and analyzes the first sampling voltage and the second sampling voltage to determine whether the driving voltage should be increased or decreased at present, and outputs it through the DAC to control the voltage value loaded to the first heater, the second phase shifter 908 and the second heater, and the adjustment voltage of the first heater and the second heater is less than the adjustment voltage of the second phase shifter 908, so as to change the refractive index of the first interferometer arm 902 and the second interferometer arm 903, thereby changing the optical path difference between the two interferometer arms to ensure that the two interferometer arms produce a constant phase difference, so that the operating point of the MZM modulator is locked at the optimal operating point.

[0090] In some embodiments, a first phase shifter 907 and a first heater are provided on the first interferometer arm 902, and a second phase shifter 908 and a second heater are provided on the second interferometer arm 903. The first sampling voltage of the optical signal output by the first interferometer arm 902 is collected by the first optical power detection component 920, and the second sampling voltage of the optical signal output by the second interferometer arm 903 is collected by the second optical power detection component 930. The MCU compares and analyzes the first sampling voltage and the second sampling voltage to determine whether the driving voltage should be increased or decreased at present, and outputs it through the DAC to control the voltage value loaded to the first phase shifter 907, the first heater, the second phase shifter 908 and the second heater, and the adjustment voltage of the first heater and the second heater is less than the adjustment voltage of the first phase shifter 907 and the second phase shifter 908, so as to change the refractive index of the first interferometer arm 902 and the second interferometer arm 903, thereby changing the optical path difference of the two interferometer arms to ensure that the two interferometer arms produce a constant phase difference, so that the working point of the MZM modulator is locked at the optimal working point.

[0091] When a phase shifter is set on the interference arm, a phase shifter can be set on both the first interference arm 902 and the second interference arm 903. The MCU controls the driving voltage loaded on the two phase shifters, and sets the driving voltage from low to high, for example, 0 to 3V. The MCU draws a phase shifter voltage-power response curve based on the first sampling voltage and the second sampling voltage obtained by the first optical power detection component 920 and the second optical power detection component 930, and selects the phase shifter with the highest efficiency. The phase shifter on the other path can be discarded.

[0092] Since a heater is provided on the interference arm, the MCU controls the driving voltage loaded to the two heaters and sets the driving voltage from low to high. The MCU draws a heater voltage-power response curve based on the first sampling voltage and the second sampling voltage obtained by the first optical power detection component 920 and the second optical power detection component 930.

[0093] The phase shifter voltage-power response curve and the heater voltage-power response curve are combined to obtain the phase shifter voltage value and the heater voltage value corresponding to the preset power. In order to reduce the current injected into the heater, the driving voltage loaded on the phase shifter is adjusted in a large range to roughly adjust the power curve, and then the driving voltage loaded on the heater is adjusted in a small range to provide a small current to the heater to fine-tune the power curve, so that the operating point of the MZM modulator is locked at the optimal operating point under the joint control of the phase shifter and the heater.

[0094] In some embodiments, the MCU may load 90% of the driving voltage to the phase shifter and load 10% of the driving voltage to the heater to reduce the current injected into the heater, thereby reducing the additional power consumption caused by the heating resistor.

[0095] In some embodiments, when the MCU analyzes and obtains that the first sampling voltage is equal to the second sampling voltage and is not equal to the preset voltage, the MCU outputs equal driving voltages to the first phase shifter and the second phase shifter, and outputs equal heating voltage signals to the first heater and the second heater, so that the adjusted first sampling voltage and the second sampling voltage are both equal to the preset voltage, so that the operating point of the MZM modulator is locked at the optimal operating point.

[0096] When the MCU analyzes and obtains that the first sampling voltage and the second sampling voltage are not equal and are not equal to the preset voltage, the MCU outputs unequal driving voltages to the first phase shifter and the second phase shifter, and outputs unequal heating voltage signals to the first heater and the second heater, so that the adjusted first sampling voltage and the second sampling voltage are both equal to the preset voltage, so that the operating point of the MZM modulator is locked at the optimal operating point.

[0097] In some embodiments, a piezoelectric crystal is used as a phase shifter, and the refractive index of the interferometer arm is changed by integrating a piezoelectric device on the interferometer arm of the MZM modulator. The piezoelectric crystal is a pressure-sensitive device that can work only by providing an operating voltage, and the load is very small, and basically no additional current is generated, and no additional power consumption is generated.

[0098] The phase shifter provided in the embodiments of the present disclosure is not limited to piezoelectric crystals. As long as the phase shifter works according to the driving voltage and does not generate additional power consumption, it belongs to the protection scope of the present disclosure.

[0099] In some embodiments, after the MCU obtains the first sampled voltage and the second sampled voltage, it may also generate a power response curve according to the first sampled voltage, the second sampled voltage, the driving voltage output to the phase shifter, and the driving voltage output to the heater. The MCU compares the power response curve with a preset power response curve. When the power response curve is inconsistent with the preset power response curve, the MCU adjusts the driving voltage output to the phase shifter according to the corresponding driving voltage in the preset power response curve to coarsely adjust the power response curve; then the MCU adjusts the driving voltage output to the heater according to the corresponding driving voltage in the preset power response curve, the adjusted voltage output to the heater is less than the adjusted voltage output to the phase shifter, and the roughly adjusted power response curve is fine-tuned to make the adjusted power response curve consistent with the preset power response curve, so that the operating point of the MZM modulator is locked at the optimal operating point.

[0100] MCU can fit the curve according to the relationship between the obtained optical power value, the driving voltage output to the phase shifter and the driving voltage output to the heater, store it in MCU, and make temperature compensation, and save it as a LUT table for the long-term operation of the optical module. When the working environment of the optical module changes, MCU automatically reads the LUT value for calibration to ensure that the optical module can be stably locked at the optimal working point under different conditions.

[0101] The optical module provided by the present invention adds a phase shifter to the two interference arms of the optical modulator, and roughly adjusts the phase difference of the optical signals output by the two interference arms by controlling the driving voltage loaded to the phase shifter, and then finely adjusts the phase difference of the optical signals output by the two interference arms by controlling the driving voltage loaded to the heater, thereby reducing the driving voltage loaded to the heater, thereby reducing the power consumption of the optical module, and further improving the signal quality transmitted by the optical module.

[0102] The above is only a specific embodiment of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any changes or substitutions that can be thought of by any person skilled in the art within the technical scope disclosed in the present disclosure should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. An optical module, characterized in that: include: Circuit boards; A light source, electrically connected to the circuit board, and configured to emit direct current light that does not carry data; an optical modulation chip, electrically connected to the circuit board, the optical modulation chip comprising an optical modulator, the optical modulator being used to modulate the direct current light not carrying data into an optical signal; wherein the optical modulator comprises two interference arms, heaters are provided on the two interference arms, and a phase shifter is provided on at least one of the interference arms, the phase shifter and the heater being used to change the refractive index of the interference arm; A first optical power detection component is disposed on one side of the interference arm, and the first optical power detection component is used to obtain a first sampling voltage according to the optical signal output by the interference arm; A second optical power detection component is disposed on one side of the other interference arm, and the second optical power detection component is used to obtain a second sampling voltage according to the optical signal output by the interference arm; an MCU, electrically connected to the circuit board, the MCU outputting driving voltages to the phase shifter and the heater respectively, the MCU being configured to receive the first sampling voltage and the second sampling voltage, and when the first sampling voltage and the second sampling voltage are not equal to a preset voltage, adjusting the driving voltage output to the phase shifter to perform a coarse adjustment on the first sampling voltage and / or the second sampling voltage; The driving voltage output to the heater is adjusted, wherein the adjustment voltage of the heater is smaller than the adjustment voltage of the phase shifter, so as to fine-tune the first sampling voltage and the second sampling voltage, so as to adjust the first sampling voltage and the second sampling voltage to the preset voltage.

2. The optical module according to claim 1, characterized in that: The optical modulator comprises: A first optical splitter, used for splitting the direct current light emitted by the light source and not carrying a signal into a first split light and a second split light of equal proportions; a first interference arm connected to the first beam splitter, wherein a first modulation electrode, a first phase shifter and a first heater are provided on the first interference arm, wherein the first modulation electrode is used to modulate the first beam splitting to obtain a first modulated beam splitting; the first phase shifter is electrically connected to the first heater and the MCU, and the first phase shifter and the first heater are used to change the refractive index of the first interference arm; The second interference arm is connected to the first spectrometer, and a second modulation electrode and a second heater are provided on the second interference arm. The second modulation electrode is used to modulate the second spectrometer to obtain the second modulated spectrometer. The second heater is electrically connected to the MCU, and the second heater is used to heat or cool the second interference arm to change the refractive index of the second interference arm.

3. The optical module according to claim 1, characterized in that: The optical modulator comprises: A first optical splitter, used for splitting the direct current light emitted by the light source and not carrying a signal into a first split light and a second split light of equal proportions; a first interference arm connected to the first beam splitter, wherein a first modulation electrode and a first heater are disposed on the first interference arm, wherein the first modulation electrode is used to modulate the first beam splitting to obtain a first modulated beam splitting; and the first heater is electrically connected to the MCU, wherein the first heater is used to heat or cool the first interference arm to change the refractive index of the first interference arm; The second interference arm is connected to the first spectrometer, and a second modulation electrode, a second phase shifter and a second heater are provided on the second interference arm. The second modulation electrode is used to modulate the second spectrometer to obtain the second modulated spectrometer; the second phase shifter is electrically connected to the second heater and the MCU, and the second phase shifter and the second heater are used to change the refractive index of the second interference arm.

4. The optical module according to claim 1, characterized in that: The optical modulator comprises: A first optical splitter, used for splitting the direct current light emitted by the light source and not carrying a signal into a first split light and a second split light of equal proportions; a first interference arm connected to the first beam splitter, wherein a first modulation electrode, a first phase shifter and a first heater are provided on the first interference arm, wherein the first modulation electrode is used to modulate the first beam splitting to obtain a first modulated beam splitting; the first phase shifter is electrically connected to the first heater and the MCU, and the first phase shifter and the first heater are used to change the refractive index of the first interference arm; The second interference arm is connected to the first spectrometer, and a second modulation electrode, a second phase shifter and a second heater are provided on the second interference arm. The second modulation electrode is used to modulate the second spectrometer to obtain the second modulated spectrometer; the second phase shifter is electrically connected to the second heater and the MCU, and the second phase shifter and the second heater are used to change the refractive index of the second interference arm.

5. The optical module according to any one of claims 2 to 3, characterized in that: The optical modulator further comprises: a second optical splitter connected to the first interference arm, the second optical splitter being used to split the first modulated light into first modulated light and first monitoring light in different proportions, wherein an optical port outputting the first monitoring light is connected to the first optical power detection component; a third optical splitter, connected to the second interference arm, and used for splitting the second modulated light into second modulated light and second monitoring light in different proportions, wherein an optical port for outputting the second monitoring light is connected to the second optical power detection component; A combiner is used to combine the first modulated light and the second modulated light, and couple the combined light into emission light.

6. The optical module according to claim 1, characterized in that: The MCU is also configured to generate a power response curve based on the first sampling voltage, the second sampling voltage, the driving voltage output to the phase shifter, and the driving voltage output to the heater. When the power response curve is inconsistent with a preset power response curve, the driving voltage output to the phase shifter is adjusted to coarsely adjust the power response curve; and the driving voltage output to the heater is adjusted to finely adjust the power response curve.

7. The optical module according to claim 4, characterized in that: The MCU is also configured to, when the first sampling voltage is equal to the second sampling voltage and is not equal to the preset voltage, output equal driving voltages to the first phase shifter and the second phase shifter, and output equal heating current signals to the first heater and the second heater, so that the adjusted first sampling voltage and the second sampling voltage are both equal to the preset voltage.

8. The optical module according to claim 4, characterized in that: The MCU is also configured to, when the first sampling voltage is unequal to the second sampling voltage and is unequal to the preset voltage, output unequal driving voltages to the first phase shifter and the second phase shifter, and output unequal heating current signals to the first heater and the second heater, so that the adjusted first sampling voltage and the second sampling voltage are both equal to the preset voltage.

9. The optical module according to claim 1, characterized in that: The optical modulation chip is a thin-film lithium niobate chip, and the phase shifter is a piezoelectric crystal.

10. The optical module according to claim 1, characterized in that: When the MCU adjusts the first sampling voltage and the second sampling voltage to the preset voltage, the optical modulator is at an optimal working point.

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