Optical module

Abstract

The invention provides an optical module, an amplification circuit comprises an inverting sub-circuit and an amplification sub-circuit, a reference voltage is connected to the non-inverting input end of the inverting sub-circuit, an MCU is connected with the inverting input end of the inverting sub-circuit and the first non-inverting input end of an amplification chip, and the output end of the inverting sub-circuit is connected with the second non-inverting input end of the amplification chip. A first inverted input end of the amplification chip is connected with the first resistor and the second resistor, the second resistor is connected with a first output end of the amplification chip and the shifter, a second inverted input end of the amplification chip is connected with the third resistor and the fourth resistor, and the fourth resistor is connected with a second output end of the amplification chip and the shifter. And the MCU stores the target frequency, the target bias and the target amplitude of the driving signal. Through the target frequency, the target bias and the target amplitude of the driving signal, the shifter can be located at the optimal working point, the optical power of the light emitted by the tunable laser reaches the target optical power, and the line width and the intensity noise are within the specified qualified range.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of optical fiber communication, in particular to an optical module. BACKGROUND

[0002] The tunable laser comprises a gain chip, a wavelength selector, a phase shifter, an end mirror, a wave plate and a photodetector located below the wave plate, and the end mirror is fixed on the shifter. The shifter vibrates back and forth under the action of the driving signal output by the MCU, the photodetector monitors the feedback signal, and the phase shifter is adjusted in real time according to the feedback signal to realize locking of the wavelength.

[0003] The frequency, bias and amplitude of the driving signal output by the MCU are fixed. Due to the different physical parameters of the shifter and the mirror, the driving signal with fixed frequency, fixed bias and single amplitude may cause the shifter not to be at the optimal working point, resulting in high line width and intensity noise indicators. SUMMARY

[0004] The application provides an optical module, and the optical power of light emitted by a tunable laser reaches a target optical power, and the line width and intensity noise are within a specified qualified range.

[0005] An optical module comprises:

[0006] A tunable laser comprises a shifter;

[0007] A circuit board is provided with an MCU and an amplification circuit, the amplification circuit comprises a reference source sub-circuit, an inverting sub-circuit and an amplification sub-circuit, the MCU controls the reference source sub-circuit to output a reference voltage, the output end of the reference source sub-circuit is connected with the positive input end of the inverting sub-circuit, the inverting input end of the inverting sub-circuit is connected with the output end of the MCU, the amplification sub-circuit comprises an amplification chip, a first resistor, a second resistor, a third resistor and a fourth resistor, the first positive input end of the amplification chip is connected with the output end of the MCU, the second positive input end of the amplification chip is connected with the output end of the inverting sub-circuit, the first inverting input end of the amplification chip is connected with one end of the first resistor and the second resistor, the other end of the first resistor is grounded, the other end of the second resistor is connected with the first output end of the amplification chip and the first input end of the shifter, the second inverting input end of the amplification chip is connected with one end of the third resistor and the fourth resistor, the other end of the third resistor is grounded, and the other end of the fourth resistor is connected with the second output end of the amplification chip and the second input end of the shifter;

[0008] The MCU stores a target frequency of a driving signal, a target bias of the driving signal and a target amplitude of the driving signal, the target frequency of the driving signal is obtained by the MCU by adjusting the frequency of the output driving signal, the target bias of the driving signal is obtained by the MCU by adjusting the reference voltage, and the target amplitude of the driving signal is obtained by the MCU by adjusting the ratio of the first resistor and the second resistor and the ratio of the third resistor and the fourth resistor.

[0009] An optical module comprises:

[0010] A tunable laser comprises a shifter for emitting light.

[0011] A circuit board is provided with an MCU and an amplification circuit, the amplification circuit comprises a reference source sub-circuit, an inverting sub-circuit and an amplification sub-circuit, the MCU controls the reference source sub-circuit to output a reference voltage, the output end of the reference source sub-circuit is connected with the positive input end of the inverting sub-circuit, the inverting input end of the inverting sub-circuit is connected with the output end of the MCU, the amplification sub-circuit comprises an amplification chip, a first resistor, a second resistor, a third resistor and a fourth resistor, the first positive input end of the amplification chip is connected with the output end of the MCU, the second positive input end of the amplification chip is connected with the output end of the inverting sub-circuit, the first inverting input end of the amplification chip is connected with one end of the first resistor and the second resistor, the other end of the first resistor is grounded, the other end of the second resistor is connected with the first output end of the amplification chip and the first input end of the shifter, the second inverting input end of the amplification chip is connected with one end of the third resistor and the fourth resistor, the other end of the third resistor is grounded, and the other end of the fourth resistor is connected with the second output end of the amplification chip and the second input end of the shifter.

[0012] The MCU stores a first target value, a second target value, a third target value, a target frequency of a driving signal, a target bias of the driving signal and a target amplitude of the driving signal, the tunable laser locks the wavelength under the action of the first target value and the second target value, the tunable laser locks the phase under the action of the third target value, the target frequency of the driving signal is obtained by the MCU by adjusting the frequency of the output driving signal, the target bias of the driving signal is obtained by the MCU by adjusting the reference voltage, and the target amplitude of the driving signal is obtained by the MCU by adjusting the ratio of the first resistor and the second resistor and the ratio of the third resistor and the fourth resistor.

[0013] A coherent light assembly is located on the circuit board and connected with the tunable laser to realize the conversion of optical and electrical signals.

[0014] Beneficial effects: The application provides a light module, which comprises a tunable laser and a circuit board, the tunable laser comprises a shifter. The circuit board is provided with an MCU and an amplification circuit. The input end of the amplification circuit is connected with the MCU, and the output end of the amplification circuit is connected with the shifter. The amplification circuit is used for amplifying a driving signal so as to meet the requirement of the shifter. The amplification circuit comprises a reference source sub-circuit, an inverting sub-circuit and an amplification sub-circuit, the MCU controls the reference source sub-circuit to output a reference voltage, the output end of the reference source sub-circuit is connected with the non-inverting input end of the inverting sub-circuit, the inverting input end of the inverting sub-circuit is connected with the MCU, the output end of the inverting sub-circuit is connected with the second non-inverting input end of the amplification chip, the MCU is connected with the first non-inverting input end of the amplification chip, the first inverting input end of the amplification chip is connected with one end of a first resistor and one end of a second resistor, the other end of the first resistor is grounded, the other end of the second resistor is connected with the first output end of the amplification chip and the first input end of the shifter, the second inverting input end of the amplification chip is connected with one end of a third resistor and one end of a fourth resistor, the other end of the third resistor is grounded, the other end of the fourth resistor is connected with the second output end of the amplification chip and the second input end of the shifter. The MCU can make the phase locking most stable by adjusting the frequency of the output driving signal. The MCU can make the optical power reach the target optical power by adjusting the bias of the driving signal through adjusting the reference voltage. The MCU can make the linewidth and the intensity noise be in the specified qualified range by adjusting the amplitude of the driving signal through adjusting the ratio of the first resistor and the second resistor and the ratio of the third resistor and the fourth resistor. The MCU stores the target frequency of the driving signal, the target bias of the driving signal and the target amplitude of the driving signal, the target frequency of the driving signal is obtained by the MCU by adjusting the frequency of the output driving signal, the target bias of the driving signal is obtained by the MCU by adjusting the reference voltage, and the target amplitude of the driving signal is obtained by the MCU by adjusting the ratio of the first resistor and the second resistor and the ratio of the third resistor and the fourth resistor. The target frequency of the driving signal, the target bias of the driving signal and the target amplitude of the driving signal can make the shifter be at the best working point, reduce the power consumption of the tunable laser, make the optical power of the light emitted by the tunable laser reach the target optical power, and make the linewidth and the intensity noise be in the specified qualified range. The MCU outputs the driving signal to the shifter, the target frequency of the driving signal makes the phase locking most stable, the target bias of the driving signal makes the optical power reach the target optical power, and the target amplitude of the driving signal makes the linewidth and the intensity noise be in the specified qualified range. In the application, the target frequency of the driving signal, the target bias of the driving signal and the target amplitude of the driving signal stored in the MCU can make the shifter be at the best working point, reduce the power consumption of the tunable laser, make the optical power of the light emitted by the tunable laser reach the target optical power, and make the linewidth and the intensity noise be in the specified qualified range. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort based on these drawings.

[0016] Figure 1 A partial structure diagram of an optical communication system according to some embodiments is provided.

[0017] Figure 2 A partial structure diagram of a host computer according to some embodiments is provided.

[0018] Figure 3 A structure diagram of an optical module according to some embodiments is provided.

[0019] Figure 4 An exploded view of an optical module according to some embodiments is provided.

[0020] Figure 5 A structure diagram of a tunable laser according to some embodiments is provided.

[0021] Figure 6 An exploded view of a tunable laser according to some embodiments is provided.

[0022] Figure 7 A structure diagram of an optical assembly according to some embodiments is provided.

[0023] Figure 8 An internal structure diagram of an optical module according to some embodiments is provided.

[0024] Figure 9 A relationship diagram of an MCU, an amplification circuit and a shifter according to some embodiments is provided.

[0025] Figure 10 A schematic diagram of an amplification circuit according to some embodiments is provided.

[0026] Figure 11 A structure diagram of an amplification circuit according to some embodiments is provided.

[0027] Figure 12 A circuit diagram of an amplification chip according to some embodiments is provided.

[0028] Figure 13 A flow of an index optimization method according to some embodiments is provided. Figure 1

[0029] A flow of an index optimization method according to some embodiments is provided. Figure 14 Figure 2 ​​ DETAILED DESCRIPTION

[0030] Some embodiments of the present disclosure will be described in detail below with reference to the drawings. However, the described embodiments are only some embodiments of the present disclosure, not all embodiments. Based on the embodiments provided in the present disclosure, all other embodiments obtained by those of ordinary skill in the art belong to the scope of protection of the present disclosure.

[0031] Unless otherwise required by the context, throughout the specification and claims, the term "comprising" is to be interpreted as open, inclusive, meaning "including, but not limited to"; the terms "first", "second" are not to be interpreted as indicating or implying relative importance or indicating the upper limit of the number; the term "multiple" means two or more; the term "connected" should be broadly interpreted, for example, "connected" can be fixed connection, or detachable connection, or integrated, can be directly connected, or indirectly connected through an intermediate medium; The use of the terms "suitable for" or "configured to" means open and inclusive language, which does not exclude devices suitable for or configured to perform additional tasks or steps; The terms "parallel", "vertical", "same", "consistent", "flush" and the like are not limited to absolute mathematical relationships, but also include acceptable error ranges generated in practice, and also include differences based on the same design concept but due to manufacturing reasons.

[0032] In optical communication technology, in order to establish information transmission between information processing devices, information needs to be loaded onto light, and the transmission of information is realized by the propagation of light. Here, the light loaded with information is an optical signal. The optical signal can reduce the loss of optical power when transmitted in the information transmission device, so as to realize high-speed, long-distance and low-cost information transmission. The signal that the information processing device can recognize and process is an electrical signal. Information processing devices usually include optical network terminals (ONUs), gateways, routers, switches, mobile phones, computers, servers, tablets, televisions, etc., and information transmission devices usually include optical fibers and optical waveguides, etc.

[0033] The optical module can realize mutual conversion between optical signals and electrical signals between the information processing device and the information transmission device. For example, at least one of the optical signal input end or the optical signal output end of the optical module is connected with 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 with an optical network terminal; a first optical signal from the optical fiber is transmitted to the optical module, the optical module converts the first optical signal into a first electrical signal, and transmits the first electrical signal to the optical network terminal; a second electrical signal from the optical network terminal is transmitted to the optical module, the optical module converts the second electrical signal into a second optical signal, and transmits the second optical signal to the optical fiber. Since information transmission can be performed between multiple information processing devices through electrical signals, at least one of the multiple information processing devices needs to be directly connected with the optical module, without the need for all the information processing devices to be directly connected with the optical module. Here, the information processing device directly connected with the optical module is referred to as a host computer of the optical module. In addition, the optical signal input end or the optical signal output end of the optical module can be referred to as an optical port, and the electrical signal input end or the electrical signal output end of the optical module can be referred to as an electrical port.

[0034] Figure 1 A partial structure diagram of an optical communication system according to some embodiments is provided. As shown in Figure 2 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.

[0035] One end of the optical fiber 101 extends to the direction of the remote information processing device 1000, and the other end of the optical fiber 101 is connected with 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 totally reflected direction can almost maintain the original optical power. The optical signal is totally reflected multiple times 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 and low-power-loss information transmission.

[0036] The optical communication system can include one or more optical fibers 101, and the optical fiber 101 can be detachably connected with the optical module 200 or fixedly connected. The host computer 100 is configured to provide a data signal to the optical module 200, or receive a data signal from the optical module 200, or monitor or control the working state of the optical module 200.

[0037] The host computer 100 includes a housing substantially in the shape of a rectangular cuboid, and an optical module interface 102 disposed on the housing. The optical module interface 102 is configured to access the optical module 200, so that the host computer 100 and the optical module 200 establish one-way or two-way electrical signal connection.

[0038] The host computer 100 further comprises an external electrical interface which can access an electrical signal network. For example, the external electrical interface comprises a Universal Serial Bus (USB) interface or a network cable interface 104 configured to access a network cable 103 to establish a unidirectional or bidirectional electrical signal connection between the host computer 100 and 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 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, a third electrical signal emitted 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. The second optical signal is transmitted in the optical fiber 101 to the remote information processing device 1000. 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. 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. 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 converting optical signals and electrical signals. In the conversion process of the optical signals and the electrical signals, the information does not change, and the encoding and decoding methods of the information can change.

[0039] The host computer 100 further comprises an external electrical interface which can access an electrical signal network. For example, the external electrical interface comprises a Universal Serial Bus (USB) interface or a network cable interface 104 configured to access a network cable 103 to establish a unidirectional or bidirectional electrical signal connection between the host computer 100 and 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 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, a third electrical signal emitted 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. The second optical signal is transmitted in the optical fiber 101 to the remote information processing device 1000. 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. 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. 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 converting optical signals and electrical signals. In the conversion process of the optical signals and the electrical signals, the information does not change, and the encoding and decoding methods of the information can change.

[0040] Figure 2 A partial structure diagram of a host computer according to some embodiments is provided. In order to clearly show the connection relationship between the optical module 200 and the host computer 100, Figure 3 Only the structure of the host computer 100 related to the optical module 200 is shown. As Figure 4 shown, the host computer 100 further comprises a PCB circuit board 105 arranged in the housing, a cage 106 arranged on the surface of the PCB circuit board 105, a heat sink 107 arranged on the cage 106, and an electrical connector arranged 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.

[0041] The light module 200 is inserted into the cage 106 of the host computer 100, and the light module 200 is fixed by the cage 106. The heat generated by the light module 200 is conducted to the cage 106, and then diffused through the heat sink 107. After the light module 200 is inserted into the cage 106, the electrical port of the light module 200 is connected to the electrical connector inside the cage 106, so that the light module 200 and the host computer 100 establish a bidirectional electrical signal connection. In addition, the optical port of the light module 200 is connected to the optical fiber 101, so that the light module 200 and the optical fiber 101 establish a bidirectional optical signal connection.

[0042] Figure 3 A structural diagram of a light module according to some embodiments, Figure 4 An exploded view of a light module according to some embodiments. As shown in Figure 3 and Figure 3 The light module 200 includes a shell, a circuit board 300 arranged in the shell, a tunable laser 901, and a coherent light assembly 902.

[0043] The shell includes an upper shell 201 and a lower shell 202. The upper shell 201 is covered on the lower shell 202 to form the above-mentioned shell with two openings 204 and 205. The outer contour of the shell generally presents a square body.

[0044] In some embodiments, the lower shell 202 includes a bottom plate 2021 and two lower side plates 2022 arranged perpendicularly to the bottom plate 2021 on both sides of the bottom plate 2021. The upper shell 201 includes a cover plate 2011, which is covered on the two lower side plates 2022 of the lower shell 202 to form the above-mentioned shell.

[0045] In some embodiments, the lower shell 202 includes a bottom plate 2021 and two lower side plates 2022 arranged perpendicularly to the bottom plate 2021 on both sides of the bottom plate 2021. The upper shell 201 includes a cover plate 2011 and two upper side plates arranged perpendicularly to the cover plate 2011 on both sides of the cover plate 2011. The two upper side plates are combined with the two lower side plates 2022 to realize that the upper shell 201 is covered on the lower shell 202.

[0046] The direction of the line connecting the two openings 204 and 205 can be consistent with the length direction of the light module 200, or can be inconsistent with the length direction of the light module 200. For example, the opening 204 is located at the end (right end) of the light module 200, and the opening 205 is also located at the end of the light module 200. Figure 4 Figure 5 ​Or, 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 fingers of the circuit board 300 extend from the electrical port and are inserted into the electrical connector of the host computer 100; the opening 205 is an optical port configured to access the external optical fiber 101 so that the optical fiber 101 is connected to the tunable laser 900 and the coherent light assembly 902 in the optical module 200.

[0047] The upper shell 201 and the lower shell 202 are combined to facilitate the installation of the circuit board 300, the tunable laser 900, and the coherent light assembly 902 into the shells, and the shells can encapsulate and protect the devices. In addition, when the circuit board 300, the tunable laser 900, and the coherent light assembly 902 are assembled, the positioning components, heat dissipation components, and electromagnetic shielding components of these devices can be easily arranged, which facilitates the automated production.

[0048] In some embodiments, the upper shell 201 and the lower shell 202 are made of metal materials, which are beneficial to electromagnetic shielding and heat dissipation.

[0049] In some embodiments, the optical module 200 further includes an unlocking component 600 located outside the shell of the optical module 200. The unlocking component 600 is configured to achieve the 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.

[0050] For example, the unlocking component 600 is located outside the two lower side plates 2022 of the lower shell 202 and includes a clamping component matched with the cage 106 of the host computer 100. When the optical module 200 is inserted into the cage 106, the clamping component of the unlocking component 600 fixes the optical module 200 in the cage 106. When the unlocking component 600 is pulled, the clamping component of the unlocking component 600 moves, thereby changing the connection relationship between the clamping component and the host computer, releasing the fixation between the optical module 200 and the host computer, and allowing the optical module 200 to be pulled out of the cage 106.

[0051] Circuit board 300 includes circuit traces, electronic components, and chips. The circuit traces connect the electronic components and chips according to the circuit design to achieve functions such as power supply, electrical signal transmission, and grounding. Electronic components may include, for example, capacitors, resistors, transistors, and metal-oxide-semiconductor field-effect transistors (MOSFETs). Chips may include, for example, microcontroller units (MCUs), laser driver chips, transimpedance amplifiers (TIAs), limiting amplifiers (LIAs), clock and data recovery chips (CDRs), power management chips, and digital signal processing (DSP) chips.

[0052] Circuit board 300 is generally a rigid circuit board. Due to its relatively hard material, the rigid circuit board can also perform a load-bearing function. For example, the rigid circuit board can stably support the aforementioned 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.

[0053] The circuit board 300 also includes gold fingers formed on its end surfaces, each gold finger consisting of a plurality of independent pins. The circuit board 300 is inserted into a cage 106 and is electrically connected to an electrical connector within the cage 106 by the gold fingers. The gold fingers may be located only on one side of the surface of the circuit board 300 (e.g., ...). Figure 6 The upper surface shown can also be positioned on the upper and lower surfaces of the circuit board 300 to provide a greater number of pins, thus adapting to applications with high pin count requirements. The gold fingers are 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, and data signal transmission. Of course, flexible circuit boards are also used in some optical modules. Flexible circuit boards are generally used in conjunction with rigid circuit boards as a supplement to rigid circuit boards.

[0054] The tunable laser 901 is connected to the circuit board 300 and is used to emit light.

[0055] The optical module also includes a transmitting fiber optic adapter 700 and a receiving fiber optic adapter 701. The transmitting fiber optic adapter 700 is used to transmit high-frequency optical signals, and the receiving fiber optic adapter 701 is used to receive high-frequency optical signals.

[0056] The coherent light assembly 902 is disposed on the circuit board and is configured to convert high-speed optical signals. Specifically, the coherent light assembly 902 includes a light emitting interface, a light receiving interface, and a local light interface. The light emitting interface extends out of the first optical fiber, the light receiving interface extends out of the second optical fiber, and the local light interface extends out of the third optical fiber. The light emitting interface is connected to the transmitting optical fiber adapter 700, the light receiving interface is connected to the receiving optical fiber adapter 701, and the local light interface is connected to the tunable laser 901. The first optical fiber, the second optical fiber, and the third optical fiber form an optical fiber array. The coherent light assembly is connected to the transmitting optical fiber adapter, the receiving optical fiber adapter, and the tunable laser 901 through the optical fiber array. The coherent light assembly 902 is also connected to the DSP chip.

[0057] The light emitted by the tunable laser 901 is input into the coherent light assembly 902 through the local light interface and is split into two beams inside the coherent light assembly 902. One of the beams is used as a transmitting beam and is input into a coherent modulation chip inside the coherent light assembly. The transmitting beam is converted into a high-frequency optical signal under the driving of a high-frequency electrical signal from the DSP chip. The converted high-frequency optical signal is output from the light emitting interface of the module. The other beam is used as a local light beam and is coherently demodulated with a high-frequency optical signal input into the coherent light assembly 902 from the light receiving port of the module. The demodulated electrical signal is input into the DSP chip for signal processing, thereby completing the conversion of the optical signal into the electrical signal.

[0058] Figure 5 A structural diagram of the tunable laser according to some embodiments is provided. Figure 6 An exploded view of the tunable laser according to some embodiments is provided. As shown in Figure 5 and Figure 6 In some embodiments, the tunable laser 901 can include a first housing. An optical assembly 916 can be disposed inside the first housing.

[0059] As shown in Figure 5 and Figure 6 In some embodiments, the tunable laser 901 can include an internal optical fiber adapter 915. The internal optical fiber adapter 915 can be connected to the first housing so that the light signal emitted from the first housing is incident on the internal optical fiber adapter 915.

[0060] As shown in Figure 5 and Figure 6 In some embodiments, the tunable laser 901 can include a pin 914. One end of the pin 914 can be connected to the optical assembly 916. The other end of the pin 914 can be connected to the circuit board 300. One end of the pin 914 can be connected to the optical assembly 916, and the other end of the pin 914 can be connected to the circuit board 300, so that the electrical signal between the circuit board 300 and the optical assembly 916 is transmitted through the pin 914.

[0061] As shown in Figure 5 and Figure 6 In some embodiments, the first shell can include a base 913. The base 913 can be provided with fins. The fins can be provided with the optical assembly 916 to control the temperature of the optical assembly 916. The fins can be semiconductor refrigerators.

[0062] As shown in Figure 5 and Figure 6 In some embodiments, the first shell can include a first side plate 911. The bottom of the first side plate 911 can be connected with the base 913.

[0063] As shown in Figure 5 and Figure 6 In some embodiments, the first shell can include a second side plate 912. The bottom of the second side plate 912 can be connected with the base 913.

[0064] As shown in Figure 7 and Figure 7 In some embodiments, the first shell can include a first cover plate. The first cover plate can be connected with the top of the first side plate 911 and the second side plate 912. The first cover plate can be connected with the top of the first side plate 911 and the second side plate 912, and the bottom of the first side plate 911 and the second side plate 912 can be connected with the base 913, so as to form a closed first shell.

[0065] Figure 7 A structural diagram of the optical assembly according to some embodiments is shown. As shown in Figure 7 The optical assembly 916 can include a gain chip 9161. The gain chip 9161 can emit broadband light containing multiple wavelengths.

[0066] In some embodiments, the first cavity surface (i.e. the right cavity surface) of the gain chip 9161 can be coated with an anti-reflection film, so that the first cavity surface of the gain chip 9161 is a transmission surface, and thus light can be emitted through the first cavity surface of the gain chip 9161.

[0067] In some embodiments, the second cavity surface (i.e. the left cavity surface) of the gain chip 9161 can be coated with a reflective film, so that the second cavity surface of the gain chip 9161 is a reflection surface, and thus light can be reflected at the second cavity surface of the gain chip 9161.

[0068] As shown in Figure 7 In some embodiments, the optical assembly 916 can include a lens 9162. The lens 9162 can be located behind (i.e. at the right end of) the gain chip 9161. The lens 9162 is used to collimate / converge light. For example, the light emitted by the gain chip 9161 is collimated by the lens 9162, and the light converges after passing through the lens 9162 and is incident on the gain chip 9161.

[0069] like Figure 7 As shown, in some embodiments, the optical component 916 may include a first etalon 9163. The first etalon 9163 has a first light-transmitting aperture through which an optical signal passes. A first heating resistance wire is disposed around the first light-transmitting aperture. The first heating resistance wire is used to heat the first etalon 9163 to change the refractive index of the first etalon 9163, thereby changing the wavelength selected by the first etalon 9163.

[0070] In some embodiments, the MCU provides a first target value to the first heating resistance wire so that the first etalon 9163 can filter out light of a specific wavelength.

[0071] The first target value may include a first drive current target value, which is the drive current target value provided by the MCU to the first heating resistance wire. The MCU outputs the first drive current target value to the first heating resistance wire so that the resistance value of the first heating resistance wire reaches the target resistance value, thereby making the refractive index of the first etalon 9163 reach the target refractive index, so that the first etalon 9163 can filter out light of a specific wavelength.

[0072] like Figure 7 As shown, in some embodiments, optical component 916 may include phase shifter 9164. Phase shifter 9164 may be located behind first etalon 9163. Phase shifter 9164 has a third light-passing aperture through which the optical signal passes. A third heating resistance wire is disposed around the third light-passing aperture. The third heating resistance wire is used to heat phase shifter 9164 to change the refractive index of phase shifter 9164, thereby changing the optical path of the optical signal within phase shifter 9164, and thus achieving phase locking.

[0073] In some embodiments, the MCU provides a third target value to the third heating resistance wire so that the phase shifter 9164 can achieve phase locking.

[0074] The third target value may include the third drive current target value. The third drive current target value is the drive current target value given to the third heating resistor. The MCU outputs the third drive current target value to the third heating resistor so that the resistance value of the third heating resistor reaches the target resistance value, and the refractive index of the phase shifter 9164 reaches the target refractive index, thereby realizing the optical path of the optical signal within the phase shifter 9164, and thus achieving phase locking of the optical signal.

[0075] like Figure 7As shown, in some embodiments, optical component 916 may include a second etalon 9165. The second etalon 9165 may be located behind the phase shifter 9164. The second etalon 9165 has a second light-transmitting aperture through which the optical signal passes. A second heating resistance wire is disposed around the second light-transmitting aperture. The second heating resistance wire is used to heat the second etalon 9165 to change the refractive index of the second etalon 9164, thereby changing the wavelength selected by the second etalon 9165.

[0076] In some embodiments, the MCU provides a second target value to the second heating resistance wire so that the second etalon 9165 can filter out light of a specific wavelength.

[0077] The second target value may include a second drive current target value. The second drive current target value is the target drive current value given to the second heating resistance wire. The MCU outputs the second drive current target value to the second heating resistance wire so that the resistance value of the second heating resistance wire reaches the target resistance value, thereby making the refractive index of the second etalon 9165 reach the target refractive index, so that the second etalon 9165 can filter out light of a specific wavelength.

[0078] The first etalon 9163 and the second etalon 9164 constitute a wavelength selection component, which can filter out characteristic wavelength light signals from broadband light. That is, the wavelengths filtered by the first etalon 9163 and the wavelengths filtered by the second etalon 9164 overlap, and the overlapping wavelengths are the light of a specific wavelength selected by the wavelength selection component.

[0079] like Figure 7 As shown, in some embodiments, optical component 916 may include mirror 9166. Mirror 9166 may be located behind the second etalon 9165.

[0080] like Figure 7 As shown, in some embodiments, optical component 916 may include a shifter 9167. The shifter 9167 is located below the mirror 9166 to fix the mirror 9166. The shifter 9167 can jitter back and forth under the action of a drive signal, so that the mirror 9166 can jitter slightly in the left-right direction. For example, the shifter 9167 may be piezoelectric ceramic.

[0081] like Figure 8 As shown, in some embodiments, optical component 916 may include a first waveplate 9168. The first waveplate 9168 may be located behind the mirror 9166. The first waveplate 9168 can transmit light partially and reflect it partially.

[0082] like Figure 9As shown in some embodiments, the optical assembly 916 can include a photodetector 9169. The photodetector 9169 can be located below the first wave plate 9168, so that the photodetector 9169 can receive the light reflected by the first wave plate 9168. The photodetector 9169 can convert the received light into a feedback signal.

[0083] Figure 7 An internal structure diagram of the optical module according to some embodiments. Figure 8 A relationship diagram of the MCU, the amplification circuit, and the shifter according to some embodiments. As shown in Figure 9 、 Figure 8 and Figure 9 As shown in some embodiments, the MCU can be disposed on the circuit board. The MCU 301 can output a single-ended driving signal. The MCU 301 can be electrically connected to the optical assembly in the tunable laser 901 through the pin 914. For example, the MCU 301 can be electrically connected to the shifter 9167 through the pin 914 to provide a driving signal to the shifter 9167, so that the shifter 9167 can be back and forth dithered. The MCU 301 can be electrically connected to the photodetector 9169 through the pin 914 to obtain a feedback signal of the photodetector 9169. The MCU 301 can be electrically connected to the third heating resistor wire of the phase shifter 9164 through the pin 914 to adjust the driving current of the third heating resistor wire of the phase shifter 9164, so as to adjust the refractive index of the phase shifter 9164, thereby adjusting the optical path of the optical signal in the phase shifter 9164.

[0084] The driving signal includes a direct current driving signal and an alternating current driving signal, and the feedback signal includes an alternating current feedback signal and a direct current feedback signal. The alternating current feedback signal corresponds to the alternating current driving signal of the driving signal, and the direct current feedback signal corresponds to the direct current driving signal of the driving signal. The MCU can monitor the optical power of the tunable laser according to the direct current feedback signal. The MCU can adjust the driving current provided to the third heating resistor wire of the phase shifter 9164 according to the alternating current feedback signal to adjust the refractive index of the phase shifter 9164.

[0085] The gain chip 9161, the lens 9162, the wavelength selection assembly, the phase shifter 9164, and the mirror 9166 can constitute a resonant cavity, one end of the resonant cavity being the back cavity surface (i.e., the left cavity surface) of the gain chip 9161, and the other end of the resonant cavity being the mirror 9166. The light of a specific wavelength oscillates back and forth in the resonant cavity, i.e., the light of the specific wavelength is reflected back and forth between the back cavity surface of the gain chip 9161 and the mirror 9166.

[0086] As the refractive index of the phase shifter 9164 changes, the distance between the gain chip 9161 and the mirror 9166 can be changed, and thus the cavity length of the resonant cavity can be changed, and thus the cavity mode of the resonant cavity can be changed. Therefore, the MCU can adjust the driving current of the third heating resistor wire of the phase shifter 9164 in real time according to the feedback signal, so as to change the cavity length of the resonant cavity, and thus change the phase of the resonant cavity. When the wavelength of the phase matching (i.e., the driving current of the third heating resistor wire reaches the third target value) and the wavelength of the light selected by the wavelength selection component are aligned, the light selected by the wavelength selection component oscillates back and forth in the resonant cavity, and finally is output from the resonant cavity in the form of laser.

[0087] As shown in Figure 9 and Figure 9 In some embodiments, an amplification circuit 302 can be arranged on the circuit board 300. The input end of the amplification circuit 302 can be connected with the output end of the MCU 301 to receive the single-ended driving signal output by the MCU 301. The output end of the amplification circuit 302 can be electrically connected with the shifter 9167 through the pin 914 to provide the shifter 9167 with the required driving signal.

[0088] In some embodiments, the amplification circuit 302 can amplify the single-ended driving signal to meet the required driving signal of the shifter 9167.

[0089] The input end of the amplification circuit 302 can be connected with the output end of the MCU 301, and the output end of the amplification circuit 302 can be electrically connected with the shifter 9167 to amplify the driving signal output by the MCU 301, so that the driving signal output by the MCU 301 meets the required driving signal of the shifter 9167 after being converted by the amplification circuit 302.

[0090] As shown in Figure 10 In some embodiments, the first output end of the amplification circuit 302 can be connected with the first input end of the shifter 9167.

[0091] As shown in Figure 9 In some embodiments, the second output end of the amplification circuit 302 can be connected with the second input end of the shifter 9167.

[0092] In some embodiments, the amplification circuit 302 can convert the single-ended driving signal into a differential driving signal and amplify the differential driving signal.

[0093] The input end of the amplification circuit 302 can be connected with the output end of the MCU 301, the first output end of the amplification circuit 302 is electrically connected with the first input end of the shifter 9167, and the second output end of the amplification circuit 302 is electrically connected with the second input end of the shifter 9167, so that the amplification circuit 302 converts the single-ended driving signal into a differential driving signal and amplifies the differential driving signal, so that the driving signal output by the MCU 301 meets the requirements of the shifter 9167 after conversion by the amplification circuit 302.

[0094] In some embodiments, the driving signal output by the MCU 301 has a fixed frequency, a fixed bias and a single amplitude. Due to the physical parameters of the shifter and the mirror, the driving signal with a fixed frequency, a fixed bias and a single amplitude may not be at the optimal working point, resulting in high power consumption, high line width and high intensity noise index of the tunable laser.

[0095] To solve this problem, in some embodiments, the MCU 301 outputs a driving signal with an adjustable frequency, a fixed bias and a single amplitude, and the amplification circuit 302 is adjusted so that the driving signal output by the amplification circuit 302 has a variable frequency, a variable bias and a variable amplitude, so that the shifter can be at the optimal working point, reducing the power consumption of the tunable laser while optimizing the line width and intensity noise index.

[0096] Figure 10 A schematic diagram of the amplification circuit according to some embodiments is provided. As shown in Figure 9 and Figure 10 In some embodiments, the amplification circuit 302 can include an inverting sub-circuit 322. The first input end of the inverting sub-circuit 322 serves as the input end of the amplification circuit 302 and can be connected with the output end of the MCU 301 to receive the non-inverted driving signal provided by the MCU 301. The inverting sub-circuit 322 converts the non-inverted driving signal into an inverted driving signal, which is output through the output end of the inverting sub-circuit 322. The non-inverted driving signal provided by the MCU 301 includes a first direct current driving signal (i.e., a first bias signal) and an alternating current signal.

[0097] When only the inverting sub-circuit 322 is provided with a driving signal by the MCU 301, the non-inverted driving signal output by the MCU 301 and the inverted driving signal output by the inverting sub-circuit 322 have the same amplitude, the same frequency, opposite polarity and the same bias size.

[0098] As shown in Figure 9 and Figure 10As shown, in some embodiments, the amplifier circuit 302 may include an amplifier sub-circuit 323. The first input terminal of the amplifier sub-circuit 323 also serves as the input terminal of the amplifier circuit 302 and can be connected to the output terminal of the MCU 301 to receive the positive-phase drive signal output by the MCU 301. The second input terminal of the amplifier sub-circuit 323 can be connected to the output terminal of the inverting sub-circuit 322 to receive the inverted-phase drive signal output by the inverting sub-circuit 322. The first output terminal of the amplifier sub-circuit 323 can be connected to the first input terminal of the shifter 9167 to provide the shifter 9167 with an amplified positive-phase drive signal. The second output terminal of the amplifier sub-circuit 323 can be connected to the second input terminal of the shifter 9167 to provide the shifter 9167 with an amplified inverted-phase drive signal.

[0099] The difference between the amplified positive-phase drive signal output from the first output terminal of amplifier circuit 323 and the amplified inverted-phase drive signal output from the second output terminal of amplifier circuit 323 is _____.

[0100] like Figure 11 and Figure 11 As shown, in some embodiments, the amplifier circuit 302 may include a reference source sub-circuit 321. The input terminal of the reference source sub-circuit 321 may be connected to a power supply chip or an MCU 301 to receive a third DC drive signal provided by the power supply chip or the MCU 301. If the input terminal of the reference source sub-circuit 321 is connected to the power supply chip, then the power supply chip is connected to the MCU 301, so that the MCU 301 can control the power supply chip to supply power to the reference source sub-circuit 321.

[0101] The third DC drive signal provided by the power supply chip or MCU301, also known as the third bias signal, is a variable initial reference voltage. The reference source circuit 321 can convert the third DC drive signal into a second DC drive signal, i.e., a reference voltage, and output it through the output terminal of the reference source circuit 321. The output terminal of the reference source circuit 321 can be connected to the second input terminal of the inverter circuit 322 to provide a variable second DC drive signal, i.e., a second bias signal.

[0102] The first input terminal of the inverter sub-circuit 322 is connected to the output terminal of the MCU 301, and the second input terminal of the inverter sub-circuit 322 is connected to the output terminal of the reference source sub-circuit 321 to receive the positive drive signal and the second bias signal, and convert the positive drive signal and the second bias signal into an inverted drive signal. At this time, the inverted drive signal has the same amplitude, the same frequency, opposite polarity, and different bias magnitude as the positive drive signal output by the MCU 301.

[0103] Figure 11 This is a circuit diagram of an amplifier circuit provided according to some embodiments. For example... Figure 11As shown, in some embodiments, the reference source circuit 321 may include an emitter follower chip 3211. The non-inverting input of the emitter follower chip 3211 can be connected to a power supply chip or an MCU 301, and the inverting input of the emitter follower chip 3211 can be connected to its output.

[0104] The RF follower chip 3211 converts the third bias signal provided by the power supply chip or MCU 301 into a second bias signal and outputs it through its output terminal. The ratio of the third bias signal to the second bias signal is a first preset value. For example, the first preset value is 2, the third bias signal is 2.5V, and the second bias signal is 1.25V.

[0105] like Figure 11 As shown, in some embodiments, the reference source circuit 321 may include a twelfth resistor 3212. The twelfth resistor 3212 is used for voltage division. One end of the twelfth resistor 3212 may be connected to a power supply chip or MCU 301, and the other end of the twelfth resistor 3212 may be connected to the non-inverting input of the emitter follower chip 3211.

[0106] like Figure 11 As shown, in some embodiments, the reference source circuit 321 may include a thirteenth resistor 3213. The thirteenth resistor 3213 is used for voltage division. One end of the thirteenth resistor 3213 may be connected to the other end of the twelfth resistor 3212, and the other end of the thirteenth resistor 3213 may be grounded.

[0107] In some embodiments, the resistance values ​​of the twelfth resistor 3212 and the thirteenth resistor 3213 are equal, so that the bias signal entering the non-inverting input terminal of the emitter follower chip 3211 is half of the third bias signal provided by the power supply chip or MCU 301, thereby making the first preset value 2.

[0108] like Figure 11 As shown, in some embodiments, the reference source circuit 321 may include a fifth capacitor 3214. One end of the fifth capacitor 3214 may be connected to the other end of the twelfth resistor 3212, and the other end of the fifth capacitor 3214 is grounded, so that the fifth capacitor 3214 is connected in parallel with the thirteenth resistor 3213. The fifth capacitor 3214 is used to reduce noise from the power supply chip or MCU 301.

[0109] like Figure 11As shown in FIG. 3, in some embodiments, a fourth capacitor 3251 can be arranged between the output terminal of the reference source sub-circuit 321 and the non-inverting input terminal of the inverting sub-circuit 322. One end of the fourth capacitor 3251 can be connected to the output terminal of the reference source sub-circuit 321 or the non-inverting input terminal of the inverting sub-circuit 322, and the other end of the fourth capacitor 3251 can be grounded. The fourth capacitor 3251 is used to reduce the noise from the output terminal of the reference source sub-circuit 321.

[0110] As shown in FIG. 3, in some embodiments, the inverting sub-circuit 322 can include an inverting chip 3221. The non-inverting input terminal of the inverting chip 3221, as the non-inverting input terminal of the inverting sub-circuit 322, can be connected to the output terminal of the reference source sub-circuit 321. The output terminal of the inverting chip 3221, as the output terminal of the inverting sub-circuit 322, can be connected to the second input terminal of the amplifying sub-circuit 323. Figure 11

[0111] As shown in FIG. 3, in some embodiments, a fifth resistor 3222 can be arranged between the non-inverting input terminal of the inverting chip 3221 and the MCU 301. One end of the fifth resistor 3222, as the non-inverting input terminal of the inverting sub-circuit 322, can be connected to the output terminal of the MCU 301. The other end of the fifth resistor 3222 can be connected to the non-inverting input terminal of the inverting chip 3221. Figure 11

[0112] As shown in FIG. 3, in some embodiments, a sixth resistor 3223 can be arranged between the non-inverting input terminal of the inverting chip 3221 and the output terminal of the inverting chip 3221. One end of the sixth resistor 3223 can be connected to the non-inverting input terminal of the inverting chip 3221, and the other end of the sixth resistor 3223 can be connected to the output terminal of the inverting chip 3221. Figure 11 In some embodiments, the fifth resistor 3222 and the sixth resistor 3223 have the same resistance, so that the inverting sub-circuit 322 only has the inverting function and does not have the amplifying function. The inverting sub-circuit 322 only inverts the alternating current signal output by the MCU 301 to obtain the inverting driving signal. At this time, the bias of the inverting driving signal is the superposition of the first bias signal and the second bias signal. Therefore, the inverting driving signal has the same amplitude and frequency as the non-inverting driving signal, the opposite polarity, and the different bias size.

[0113]

[0114] Figure 11 ​​​​As shown, in some embodiments, a seventh resistor 324 may be provided between the MCU 301 and the fifth resistor 3222. One end of the seventh resistor 324 serves as the input terminal of the amplifier circuit 302 and can be connected to the output terminal of the MCU 301. The other end of the seventh resistor 324 can be connected to the first input terminal of the amplifier sub-circuit 323 or one end of the fifth resistor 3222. The seventh resistor 324 is used to filter the positive-inverting drive signal output by the MCU 301.

[0115] like Figure 11 As shown, in some embodiments, the other end of the seventh resistor 324 can be connected to one end of the third capacitor 3252, and the other end of the third capacitor 3252 is grounded. The third capacitor 3252 is used to reduce noise transmitted from the seventh resistor 324.

[0116] like Figure 11 As shown, in some embodiments, the amplifying sub-circuit 323 may include an amplifying chip 3231. The amplifying chip 3231 may include a first non-inverting input terminal (+INA). The first non-inverting input terminal (+INA) of the amplifying chip 3231 serves as the first input terminal of the amplifying sub-circuit 323 and can be connected to the other end of the seventh resistor 324. The amplifying chip 3231 may include a second non-inverting input terminal (+INB). The second non-inverting input terminal (+INB) of the amplifying chip 3231 serves as the second input terminal of the amplifying sub-circuit 323 and can be connected to the output terminal of the inverting sub-circuit 322. The amplifying chip 3231 may include a first inverting input terminal (-INA), a second inverting input terminal (-INB), a first output terminal (OUTA), and a second output terminal (OUTB). The first output terminal (OUTA) of the amplifying chip 3231 can be connected to the first input terminal of the shifter 9167. The second output terminal (OUTB) of the amplifying chip 3231 can be connected to the second input terminal of the shifter 9167.

[0117] like Figure 11 As shown, the first inverting input terminal (-INA) of the amplifier chip 3231 can be connected to one end of the first resistor 3233. The other end of the first resistor 3233 can be grounded. The first resistor 3233 can be a variable resistor.

[0118] like Figure 11 As shown, a second resistor 3232 can be provided between the first inverting input terminal (﹣INA) and the first output terminal (OUTA) of the amplifier chip 3231. One end of the second resistor 3232 can be connected to one end of the first resistor 3233, and the other end of the second resistor 3232 can be connected to the first output terminal (OUTA). The second resistor 3232 can be a variable resistor.

[0119] In some embodiments, the ratio of the first resistance 3233 to the second resistance 3232 is variable to adjust the amplification of the driving signal into the first positive input terminal (+INA), and further adjust the amplitude of the driving signal into the first positive input terminal (+INA). For example, the ratio of the first resistance 3233 to the second resistance 3232 is variable to adjust the amplification of the positive driving signal, and further adjust the amplitude of the positive driving signal.

[0120] By adjusting the ratio of the first resistance 3233 to the second resistance 3232, the amplification of the positive driving signal can be adjusted, and further the amplitude of the positive driving signal can be adjusted.

[0121] As shown in FIG. 33, the second negative input terminal (-INB) of the amplification chip 3231 can be connected to one end of the third resistance 3235. The other end of the third resistance 3235 can be grounded. The third resistance 3235 can be a variable resistance. Figure 11 As shown in FIG. 33, the second negative input terminal (-INB) of the amplification chip 3231 can be connected to one end of the third resistance 3235. The other end of the third resistance 3235 can be grounded. The third resistance 3235 can be a variable resistance.

[0122] Figure 11 As shown in FIG. 33, the second negative input terminal (-INB) of the amplification chip 3231 and the second output terminal (OUTB) of the amplification chip 3231 can be provided with the fourth resistance 3234. One end of the fourth resistance 3234 can be connected to one end of the third resistance 3235, and the other end of the fourth resistance 3234 can be connected to the second output terminal (OUTB). The fourth resistance 3234 can be a variable resistance.

[0123] In some embodiments, the ratio of the third resistance 3235 to the fourth resistance 3234 is variable to adjust the amplification of the driving signal into the second positive input terminal (+INB), and further adjust the amplitude of the driving signal into the second positive input terminal (+INB). For example, the ratio of the third resistance 3235 to the fourth resistance 3234 is variable to adjust the amplification of the negative driving signal, and further adjust the amplitude of the negative driving signal.

[0124] By adjusting the ratio of the third resistance 3235 to the fourth resistance 3234, the amplification of the negative driving signal can be adjusted, and further the amplitude of the negative driving signal can be adjusted.

[0125] The variable resistance is an analog resistance, which is a special circuit element that can simulate different resistance values. The analog resistance mainly uses electronic elements to simulate resistance values. One end of the analog resistance is connected to the DA port of the MCU 301, so that the analog resistance can simulate different resistance values according to the analog signal output by the DA port of the MCU 301. Therefore, the MCU 301 can change the resistance value of the variable resistance.

[0126] As shown in FIG. 33, the second negative input terminal (-INB) of the amplification chip 3231 can be connected to one end of the third resistance 3235. The other end of the third resistance 3235 can be grounded. The third resistance 3235 can be a variable resistance. Figure 11 ​As shown, in some embodiments, the first output terminal (OUTA) of the amplifier chip 3231 can be connected to one end of the first capacitor 3253. The other end of the first capacitor 3253 can be grounded.

[0127] like Figure 11 As shown, in some embodiments, the second output terminal (OUTB) of the amplifier chip 3231 can be connected to one end of the second capacitor 3254. The other end of the second capacitor 3254 can be grounded.

[0128] like Figure 12 As shown, in some embodiments, the first output terminal (OUTA) of the amplifier chip 3231 can be connected to one end of the eighth resistor 326. The eighth resistor 326 is used for voltage division.

[0129] like Figure 12 As shown, in some embodiments, the other end of the eighth resistor 326 can be connected to one end of the ninth resistor 327 or the first feedback terminal of the MCU 301. The other end of the ninth resistor 327 can be grounded.

[0130] The MCU301 is connected to one end of the ninth resistor 327 to obtain the voltage of the ninth resistor 327, which is the partially amplified positive drive signal.

[0131] In some embodiments, the resistance value of the eighth resistor 326 is much greater than the resistance value of the ninth resistor 327, so that most of the amplified positive phase drive signal can be transmitted to the first input terminal of the shifter 9167, and only a very small portion of the amplified positive phase drive signal is used as the first feedback signal to reflect the magnitude of the amplified positive phase drive signal.

[0132] like Figure 12 As shown, in some embodiments, the second output terminal (OUTB) of the amplifier chip 3231 can be connected to one end of the tenth resistor 328. The tenth resistor 328 is used for voltage division.

[0133] like Figure 13 As shown, in some embodiments, the other end of the tenth resistor 328 can be connected to one end of the eleventh resistor 329 or the second feedback terminal of the MCU 301. The other end of the eleventh resistor 329 can be grounded.

[0134] The MCU301 is connected to one end of the eleventh resistor 329 to obtain the voltage of the eleventh resistor 329, which is the partially amplified inverted drive signal.

[0135] In some embodiments, the resistance value of the tenth resistor 328 is much larger than the resistance value of the eleventh resistor 329, so that most of the amplified inverted driving signal can be transmitted to the second input end of the shifter 9167, and only a very small part of the amplified inverted driving signal is the second feedback signal, to reflect the size of the amplified inverted driving signal.

[0136] After passing through the amplification circuit, the bias of the driving signal is the difference between the bias of the positive driving signal and the bias of the inverted driving signal, and the amplitude of the driving signal is the difference between the amplitude of the positive driving signal and the amplitude of the inverted driving signal.

[0137] Figure 1 The circuit diagram of the amplification chip provided according to some embodiments is shown. As shown in Figure 13 The positive input end of the first amplification chip 3231a is the first positive input end (+INA) of the amplification chip 3231, which can be connected with the other end of the seventh resistor 324 to receive the positive driving signal. The inverted input end of the first amplification chip 3231a is the first inverted input end (−INA) of the amplification chip 3231. The output end of the first amplification chip 3231a is the first output end (OUTA) of the amplification chip 3231.

[0138] As shown in Figure 14 The positive input end of the second amplification chip 3231b is the second positive input end (+INB) of the amplification chip 3231, which can be connected with the output end of the inverted sub-circuit 322 to receive the inverted driving signal. The inverted input end of the second amplification chip 3231b is the second inverted input end (−INB) of the amplification chip 3231. The output end of the second amplification chip 3231b is the second output end (OUTB) of the amplification chip 3231.

[0139] The tunable laser needs to be tested before leaving factory to determine whether the tunable laser meets the requirements, i.e. is a good product. The process of testing the tunable laser is as follows: (1) the MCU controls the driving signal of the TEC to keep the temperature of the TEC at a constant temperature. (2) the MCU provides a first target value to the first heating resistance wire and a second target value to the second heating resistance wire to make the first etalon and the second etalon select light of a specific wavelength. (3) the MCU provides a driving signal to the shifter to make the shifter jitter. (4) the MCU provides a driving current to the laser chip to make the laser chip emit a wide spectrum light containing multiple wavelengths. (5) the MCU reads the AC feedback signal of the MPD, and determines whether the phase is locked according to the AC feedback signal, the first feedback signal and the second feedback signal. If the phase is not locked, the driving current provided to the third heating resistance wire is adjusted to make the driving current of the third heating resistance wire reach the third target value, so as to realize phase locking. If the phase is locked, the process continues. At this time, the driving current is the third target value. (6) the MCU reads the DC feedback signal of the MPD, and adjusts the driving current provided to the laser chip according to the DC feedback signal of the MPD to make the optical power of the light emitted by the tunable laser reach a target optical power. However, the driving current provided to the laser chip has an upper limit value. If the driving current provided to the laser chip reaches the upper limit value, the optical power may not have reached the target optical power. If the driving current reaches the upper limit value and the optical power has not reached the target optical power, the tunable laser is a defective product. (7) the MCU can test the various indexes of the tunable laser through the test host, the oscilloscope, the noise intensity tester and the optical power meter respectively. That is, the MCU can determine whether the phase is locked through the dynamic diagram of the feedback electrical signal on the test host. The MCU can determine whether the line width is within the specified qualified range through the oscilloscope. The MCU can determine whether the noise intensity is within the specified qualified range through the noise intensity tester. The MCU can determine whether the optical power reaches the target optical power through the optical power meter.

[0140] When the phase is not locked, the tunable laser is generally determined to be a defective product. When the line width is not within the specified qualified range, the tunable laser is generally determined to be a defective product. When the noise intensity is not within the specified qualified range, the tunable laser is generally determined to be a defective product. When the optical power does not reach the target optical power, the tunable laser is generally determined to be a defective product.

[0141] In order to reduce the defective rate of the product, an index optimization method is provided to make the frequency, bias and amplitude of the driving signal output by the amplification circuit 302 variable, so that the shifter can be at the best working point, and the line width and intensity noise indexes are optimized while reducing the power consumption of the tunable laser.

[0142] Figure 2 The flow of the index optimization method provided according to some embodimentsFigure 14 As shown in FIG. 1, in some embodiments, the index optimization method can include: Figure 13

[0143] S100: MCU outputs a driving signal.

[0144] At this time, the frequency of the driving signal is an initial frequency, the bias of the driving signal is an initial bias, and the amplitude of the driving signal is an initial amplitude. The initial driving signal can make most of the shifters be at the optimal working point. However, due to the different physical parameters of the shifters and the mirrors, the driving signal with a fixed frequency, a fixed bias, and a single amplitude can make the shifters not be at the optimal working point. Therefore, it is necessary to adjust the frequency, the amplitude, and the bias of the driving signal to make the shifters be at the optimal working point.

[0145] Since only phase locking can make the tunable laser output the light with the specific wavelength required, the adjustment of the frequency of the driving signal is the first to be completed relative to the adjustment of the bias of the driving signal and the amplitude of the driving signal. Therefore, after the MCU outputs the driving signal, the frequency of the driving signal is first adjusted.

[0146] S200: MCU adjusts the frequency of the driving signal.

[0147] The tester or the test host observes the feedback electrical signal dynamic diagram on the test host. When the change of the alternating current signal in the feedback electrical signal dynamic diagram tends to be substantially zero, it indicates that the phase locking of the optical signal is most stable, and the MCU does not need to adjust the frequency of the driving signal, i.e., the test host does not need to send the first instruction to the MCU. When the change of the alternating current signal in the feedback electrical signal dynamic diagram does not tend to be zero, the MCU needs to adjust the frequency of the driving signal, i.e., the test host needs to send the first instruction to the MCU. After the MCU receives the first instruction, the frequency of the driving signal is adjusted in a step-by-step manner until the change of the alternating current signal in the feedback electrical signal dynamic diagram tends to be substantially zero and stops. At this time, the frequency of the driving signal is a preset frequency.

[0148] The feedback electrical signal dynamic diagram is obtained by the test host according to the first feedback signal and the second feedback signal sent by the MCU and the phase-inverted subtraction of the alternating feedback signal output by the photodetector 9199.

[0149] S300: MCU adjusts the ratio of the first resistor to the second resistor and the ratio of the third resistor to the fourth resistor to adjust the amplitude of the driving signal.

[0150] ​The tester or the test host observes whether the linewidth in the oscilloscope is within the specified acceptable range, and also observes whether the noise intensity in the noise intensity tester is within the specified acceptable range. If both the linewidth and noise intensity are within the specified acceptable range, the MCU does not need to adjust the ratio of the first resistor to the second resistor, and the ratio of the third resistor to the fourth resistor; that is, the test host does not need to send a second command to the MCU. If either the linewidth or the noise intensity is not within the specified acceptable range, the MCU needs to adjust the ratio of the first resistor to the second resistor, and the ratio of the third resistor to the fourth resistor; that is, the test host needs to send a second command to the MCU. After receiving the second command, the MCU adjusts the amplitude of the drive signal in steps until both the linewidth and the noise intensity are within the specified acceptable range. At this point, the amplitude of the drive signal is the target amplitude.

[0151] S400: The MCU adjusts the bias signal provided by the power supply chip to adjust the bias of the drive signal.

[0152] The tester or the test host observes whether the optical power in the optical power meter reaches the target optical power. If the optical power in the optical power meter reaches the target optical power, the MCU does not need to adjust the bias signal provided by the power supply chip, meaning the test host does not need to send a third command to the MCU. If the optical power in the optical power meter does not reach the target optical power, the MCU needs to adjust the bias signal provided by the power supply chip; that is, the test host sends a third command to the MCU. After receiving the third command, the MCU adjusts the bias signal provided by the power supply chip in a stepwise manner to adjust the bias of the drive signal. At this time, the bias of the drive signal is the target bias.

[0153] Figure 14 The flowchart of the index optimization method provided according to some embodiments ​ .like ​ As shown, in some embodiments, the metric optimization method may include:

[0154] S100: MCU output drive signal.

[0155] S200: MCU adjusts the frequency of the drive signal.

[0156] S300: The MCU adjusts the bias signal provided by the power supply chip to adjust the bias of the drive signal.

[0157] S400: The MCU adjusts the ratio of the first resistor to the second resistor, and the ratio of the third resistor to the fourth resistor, to adjust the amplitude of the drive signal.

[0158] When the performance testing method identifies which metrics fail to meet requirements, subsequent optimization of all defective products may no longer reveal which metrics are still unmet. For tunable lasers where it's impossible to determine which metrics are failing, a method such as... ​Or as shown in the index optimization method of ​ For the tunable laser which is known that some indexes do not meet the requirements, the index optimization can be directly completed in the corresponding step based on S100. For example, in the index test method, it is known that the optical power does not meet the requirements, i.e. the target optical power is not reached, and S100+S400 can complete the index optimization. In the index test method, it is known that the linewidth is not within the specified qualified range, i.e. S100+S300 can complete the index optimization.

[0159] The above steps are repeated at high temperature and low temperature respectively to compensate the temperature, so that the indexes meet the requirements. After the index optimization method, many indexes of the defective products can meet the requirements and become good products, thereby reducing the defective rate of the products.

[0160] In order to facilitate the user to use, the setting parameters of multiple wavelengths are usually stored in the register of the MCU, and the setting parameters of each wavelength at high temperature, low temperature and normal temperature can include the first target value, the second target value, the third target value, the target frequency of the driving signal, the target amplitude of the driving signal and the target bias of the driving signal. The target frequency of the driving signal is obtained by the MCU adjusting the frequency of the output driving signal in the index optimization method. The target bias of the driving signal is obtained by the MCU adjusting the reference voltage in the index optimization method. The target amplitude of the driving signal is obtained by the MCU adjusting the ratio of the first resistor and the second resistor and the ratio of the third resistor and the fourth resistor in the index optimization method.

[0161] When the user uses, the MCU first reads the setting parameters in the register, and provides the first target value, the second target value and the third target value to the corresponding devices in the tunable laser respectively, so that the tunable laser locks the wavelength under the action of the first target value and the second target value, and locks the phase under the action of the third target value; secondly, the driving signal is output to the shifter. The target frequency of the driving signal makes the phase locking most stable, the target bias of the driving signal makes the optical power reach the target optical power, and the target amplitude of the driving signal makes the linewidth and the intensity noise be within the specified qualified range. That is, the target frequency of the driving signal, the target bias of the driving signal and the target amplitude of the driving signal can make the shifter be at the best working point, reduce the power consumption of the tunable laser, make the optical power of the light emitted by the tunable laser reach the target optical power, and make the linewidth and the intensity noise be within the specified qualified range.

[0162] In some embodiments, the target amplitude of the drive signal includes the initial amplitude of the drive signal, the target ratio of the first resistor to the second resistor, and the target ratio of the third resistor to the fourth resistor. The MCU outputs the initial amplitude of the drive signal and adjusts the first resistor or the second resistor to make the ratio of the first resistor to the second resistor reach the target ratio, and adjusts the third resistor or the fourth resistor to make the ratio of the third resistor to the fourth resistor reach the target ratio, so that the amplitude of the drive signal entering the shifter reaches the target amplitude, thereby ensuring that the linewidth and intensity noise are within the specified acceptable range.

[0163] In some embodiments, the target bias of the drive signal includes an initial bias of the drive signal and a target reference voltage. The MCU outputs the initial bias of the drive signal and adjusts the reference voltage to reach the target reference voltage, so that the bias of the drive signal entering the shifter reaches the target bias, thereby achieving the target optical power.

[0164] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. An optical module characterized by comprising: The utility model relates to a kind of adjustable laser, including shifter; Circuit board is provided with MCU and amplification circuit, the amplification circuit includes reference source subcircuit, inverting subcircuit and amplification subcircuit, the MCU controls the reference source subcircuit output reference voltage, the output of the reference source subcircuit is connected with the positive input end of the inverting subcircuit, the inverting input end of the inverting subcircuit is connected with the output of the MCU, the amplification subcircuit includes amplification chip, first resistance, second resistance, third resistance and fourth resistance, the first positive input end of the amplification chip is connected with the output of the MCU, the second positive input end of the amplification chip is connected with the output of the inverting subcircuit, the first inverting input end of the amplification chip is connected with the one end of the first resistance and the second resistance, the other end of the first resistance is grounded, the other end of the second resistance is connected with the first output end of the amplification chip and the first input end of the shifter, the second inverting input end of the amplification chip is connected with the one end of the third resistance and the fourth resistance, the other end of the third resistance is grounded, the other end of the fourth resistance is connected with the second output end of the amplification chip and the second input end of the shifter; The MCU stores target frequency of drive signal, target bias of drive signal and target amplitude of drive signal, the target frequency of drive signal is obtained by adjusting the frequency of output drive signal by MCU, the target bias of drive signal is obtained by adjusting reference voltage by MCU, the target amplitude of drive signal is obtained by adjusting the ratio of first resistance and second resistance and the ratio of third resistance and fourth resistance by MCU. The first resistance or the second resistance is analog resistance, the third resistance or the fourth resistance is analog resistance, and the MCU controls the analog resistance to change the resistance value of the analog resistance.

2. The optical module according to claim 1, characterized by The inverting subcircuit includes inverting chip, fifth resistance and sixth resistance, the positive input end of the inverting chip is connected with the reference source subcircuit, the inverting input end of the inverting chip is connected with the one end of the fifth resistance and the one end of the sixth resistance, the other end of the fifth resistance is connected with the MCU, and the other end of the sixth resistance is connected with the output end of the inverting chip.

3. The optical module according to claim 1, characterized by The fifth resistance and the sixth resistance have the same resistance value, so that the inverting subcircuit has inverting function and does not have amplification function. A seventh resistance is arranged between the MCU and the amplification circuit, one end of the seventh resistance is connected with the MCU, and the other end of the seventh resistance is connected with the first positive input end of the amplification subcircuit.

4. The optical module according to claim 1, characterized by The first output end of the amplification chip is connected with one end of an eighth resistance, the other end of the eighth resistance is connected with one end of a ninth resistance and a first feedback end of the MCU, and the other end of the ninth resistance is grounded.

5. The optical module according to claim 1, characterized by The second output end of the amplification chip is connected with one end of a tenth resistance, the other end of the tenth resistance is connected with one end of an eleventh resistance and a second feedback end of the MCU, and the other end of the eleventh resistance is grounded. ​ The resistance value of the eighth resistor is greater than that of the ninth resistor, and the resistance value of the tenth resistor is greater than that of the eleventh resistor.

6. The optical module of claim 1, wherein, The reference source subcircuit comprises an emitter follower chip, a twelfth resistor and a thirteenth resistor, one end of the twelfth resistor is used for receiving an initial reference voltage, the other end of the twelfth resistor is connected with one end of the thirteenth resistor and a positive input end of the emitter follower chip, the other end of the thirteenth resistor is grounded, an inverting input end of the emitter follower chip is connected with an output end of the emitter follower chip, and the output end of the emitter follower chip is connected with a positive input end of the inverting subcircuit.

7. The optical module of claim 1, wherein, The amplification chip comprises a first amplification chip and a second amplification chip, a positive input end of the first amplification chip is connected with the MCU, an inverting input end of the first amplification chip is connected with the first resistor and one end of the second resistor, an output end of the amplification chip is connected with the other end of the second resistor and a first input end of the shifter, a positive input end of the second amplification chip is connected with the output end of the inverting subcircuit, an inverting input end of the second amplification chip is connected with the third resistor and one end of the fourth resistor, and an output end of the second amplification chip is connected with the other end of the fourth resistor and a second input end of the shifter.

8. An optical module characterized by comprising: Comprise: A tunable laser comprising a shifter for emitting light; A circuit board provided with an MCU and an amplification circuit, the amplification circuit comprising a reference source subcircuit, an inverting subcircuit and an amplification subcircuit, the MCU controls the reference source subcircuit to output a reference voltage, an output end of the reference source subcircuit is connected with a positive input end of the inverting subcircuit, an inverting input end of the inverting subcircuit is connected with an output end of the MCU, the amplification subcircuit comprises an amplification chip, a first resistor, a second resistor, a third resistor and a fourth resistor, a first positive input end of the amplification chip is connected with the output end of the MCU, a second positive input end of the amplification chip is connected with the output end of the inverting subcircuit, a first inverting input end of the amplification chip is connected with the first resistor and one end of the second resistor, the other end of the first resistor is grounded, the other end of the second resistor is connected with a first output end of the amplification chip and a first input end of the shifter, a second inverting input end of the amplification chip is connected with the third resistor and one end of the fourth resistor, the other end of the third resistor is grounded, and the other end of the fourth resistor is connected with a second output end of the amplification chip and a second input end of the shifter; The MCU stores a first target value, a second target value, a third target value, a target frequency of a driving signal, a target bias of the driving signal and a target amplitude of the driving signal, the tunable laser locks a wavelength under the first target value and the second target value, the tunable laser locks a phase under the third target value, the target frequency of the driving signal is obtained by the MCU by adjusting a frequency of the output driving signal, the target bias of the driving signal is obtained by the MCU by adjusting a reference voltage, and the target amplitude of the driving signal is obtained by the MCU by adjusting a ratio of the first resistor and the second resistor and a ratio of the third resistor and the fourth resistor; A coherent light component is located on the circuit board and connected with the tunable laser to realize conversion of an optical-electrical signal.

9. The optical module according to claim 8, characterized by The first resistor or the second resistor is an analog resistor, the third resistor or the fourth resistor is an analog resistor, and the MCU controls the analog resistor to change a resistance value of the analog resistor.

10. The optical module of claim 8, wherein, An input end of the reference source sub-circuit is connected with a power supply chip, the power supply chip is connected with the MCU, so that the MCU controls the reference source sub-circuit to output a reference voltage; or An input end of the reference source sub-circuit is connected with the MCU, so that the MCU controls the reference source sub-circuit to output a reference voltage.

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