An optical module

Abstract

The present application provides an optical module, including a semiconductor gain chip and a silicon photonic chip. The silicon photonic chip includes a directional coupler, a wavelength-tunable optical component, a wavelength sensor, a fifth power monitor, and a sixth power monitor. The directional coupler is connected to the wavelength-tunable optical component and the wavelength sensor, respectively, and the wavelength sensor is also connected to the fifth power monitor and the sixth power monitor. The wavelength-tunable optical component is used to achieve wavelength tunability. The wavelength sensor, the fifth power monitor, and the sixth power monitor constitute a wavelength-locking optical component, which is used to achieve wavelength locking. In the present application, the directional coupler, the wavelength-tunable optical component, and the wavelength-locking optical component are integrated on the silicon photonic chip, which saves space and makes the size of the light source smaller to meet production requirements; the wavelength-tunable optical component and the wavelength-locking optical component cooperate to ensure that the specific wavelength light beam output by the light source does not deviate from the preset wavelength light beam.

Description

Technical Field

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

[0002] A coherent optical module consists of a light source and a coherent component, which are connected to each other. Light from the light source enters the coherent component, where it undergoes beam splitting. One beam, acting as the transmitted light, enters the coherent modulator inside the coherent component to convert the electrical signal into an optical signal. The converted high-speed optical signal is then output from the optical transmit interface. The other beam, acting as the local oscillator light, undergoes coherent demodulation with the high-speed optical signal input from the coherent component through the optical receive interface to complete the optical-to-electrical signal conversion.

[0003] Current light sources use a combination of semiconductor gain chips and separate filters to achieve wavelength tunability. However, because multiple separate components need to be coupled and packaged within the light source, and these separate components take up a lot of space, the current light sources are too large to meet production requirements. Summary of the Invention

[0004] The present application provides an optical module so that the light source meets production requirements.

[0005] An optical module, comprising:

[0006] The light source includes a first fixing frame, a second fixing frame, a base and an upper cover;

[0007] The first fixing frame, the second fixing frame, the base and the upper cover body surround a cavity;

[0008] An optical component, located in the cavity, includes a semiconductor gain chip and a silicon photonic chip;

[0009] A silicon photonic chip is used to receive the light beam emitted by the semiconductor gain chip and filter a light beam of a specific wavelength from the light beam;

[0010] Silicon photonic chips include:

[0011] An input coupler, configured to receive a light beam emitted by the semiconductor gain chip and emit a light beam of a specific wavelength to the semiconductor gain chip;

[0012] a directional coupler connected to the input coupler;

[0013] A wavelength-tunable optical component for selecting a specific wavelength beam from a light beam;

[0014] The wavelength sensor and the wavelength tunable optical component are both connected to the directional coupler;

[0015] The fifth power monitor and the sixth power monitor are respectively connected to the wavelength sensor, and together with the wavelength sensor and the sixth power monitor, form a wavelength locking optical component, so that the wavelength locking optical component can achieve wavelength locking according to the ratio of the optical power of the fifth monitoring detector to the optical power of the sixth monitoring detector.

[0016] Beneficial effect: The present application provides an optical module, including a light source. The light source includes a first fixing frame, a second fixing frame, a base and an upper cover. The first fixing frame, the second fixing frame, the base and the upper cover surround a cavity. An optical component is arranged in the cavity, and the optical component includes a semiconductor gain chip and a silicon photonic chip. The silicon photonic chip is used to receive a light beam of a wavelength range emitted by the semiconductor gain chip, and to filter a light beam of a specific wavelength from the light beam, and is also used to emit the light beam of a specific wavelength to the semiconductor gain chip. The semiconductor gain chip and the silicon photonic chip form a resonant cavity, and the light beam of a specific wavelength is reflected back and forth between the semiconductor gain chip and the silicon photonic chip, so that the resonant cavity emits a light beam of a specific wavelength. The silicon photonic chip includes an input coupler, a directional coupler, a wavelength tunable optical component, a wavelength sensor, a fifth power monitor and a sixth power monitor. The directional coupler is connected to the input coupler, the wavelength tunable optical component and the wavelength sensor respectively through an optical waveguide, and the wavelength sensor is also connected to the fifth power monitor and the sixth power monitor through an optical waveguide. The input coupler, directional coupler, wavelength-tunable optical component, wavelength sensor, fifth power monitor, and sixth power monitor are integrated on a silicon photonic chip, saving space and making the light source smaller to meet production requirements. The input coupler is used to receive a light beam within a wavelength range emitted by a semiconductor gain chip and transmit a light beam of a specific wavelength to the semiconductor gain chip. The directional coupler is used to split the light beam of a specific wavelength. The wavelength-tunable optical component is used to filter out a light beam of a specific wavelength from a light beam within a wavelength range to achieve a wavelength tunable function. The wavelength sensor, fifth power monitor, and sixth power monitor constitute a wavelength-locking optical component. The wavelength-locking optical component characterizes whether the specific wavelength light beam deviates from the preset wavelength light beam based on the ratio of the optical power of the fifth power monitor to the optical power of the sixth power monitor to achieve a wavelength-locking function. When the specific wavelength light beam deviates from the preset wavelength light beam, the wavelength-tunable optical component is adjusted to prevent the specific wavelength light beam from deviating from the preset wavelength light beam. In this application, the input coupler, directional coupler, wavelength-tunable optical component and wavelength-locked optical component are integrated on a silicon photonic chip, which saves space and makes the size of the light source smaller to meet production needs; the wavelength-tunable optical component and the wavelength-locked optical component cooperate to ensure that the specific wavelength light beam output by the light source does not deviate from the preset wavelength light beam. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the embodiments or descriptions of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0018] Figure 1 A connection diagram of an optical communication system;

[0019] Figure 2 This is a structural diagram of an optical network terminal;

[0020] Figure 3 is a structural diagram of an optical module according to some embodiments;

[0021] Figure 4 is an exploded structural diagram of an optical module according to some embodiments;

[0022] Figure 5 A structural diagram of an optical module with a housing and unlocking components removed according to some embodiments;

[0023] Figure 6 is a structural diagram of a fiber optic adapter, a light source, a coherent component, and a circuit board according to some embodiments;

[0024] Figure 7 An exploded structural diagram of an optical module with the housing and unlocking components removed according to some embodiments;

[0025] Figure 8 is a structural diagram of a first angle of an optical fiber winding rack according to some embodiments;

[0026] Figure 9 is a structural diagram of a second angle of an optical fiber winding rack according to some embodiments;

[0027] Figure 10 is a structural diagram of a light source according to some embodiments;

[0028] Figure 11 is an exploded view of a light source according to some embodiments;

[0029] Figure 12 is a structural diagram of a first support plate according to some embodiments;

[0030] Figure 13 is a structural diagram of a first angle of a second support plate according to some embodiments;

[0031] Figure 14 is a structural diagram of a second support plate at a second angle according to some embodiments;

[0032] Figure 15is a structural diagram of a second circuit board according to some embodiments;

[0033] Figure 16 is a structural diagram of a light source according to some embodiments;

[0034] Figure 17 is an exploded view of a light source according to some embodiments;

[0035] Figure 18 is a structural diagram of a light source without an upper cover, an optical assembly, and an internal fiber optic adapter according to some embodiments;

[0036] Figure 19 is an exploded view of a light source with the upper cover, optical assembly, and internal fiber adapter removed according to some embodiments;

[0037] Figure 20 is a structural diagram of a second fixing frame according to some embodiments;

[0038] Figure 21 is a structural diagram of a first fixing frame according to some embodiments;

[0039] Figure 22 is a first cross-sectional view of a light source according to some embodiments;

[0040] Figure 23 is a second cross-sectional view of a light source according to some embodiments;

[0041] Figure 24 is a structural diagram of a first light source according to some embodiments;

[0042] Figure 25 is a structural diagram of a second light source according to some embodiments;

[0043] Figure 26 is a structural diagram of a third light source according to some embodiments;

[0044] Figure 27 is a structural diagram of a fourth light source according to some embodiments;

[0045] Figure 28 is a structural diagram of a fifth light source according to some embodiments;

[0046] Figure 29 is a structural diagram of a first silicon photonic chip according to some embodiments;

[0047] Figure 30 is a filtering curve diagram of a wavelength sensor according to some embodiments;

[0048] Figure 31 is a structural diagram of a sixth light source according to some embodiments;

[0049] Figure 32 is a structural diagram of a second silicon photonic chip according to some embodiments;

[0050] Figure 33 is a structural diagram of a third silicon photonic chip according to some embodiments;

[0051] Figure 34 A coherent component shown in an embodiment of the present application;

[0052] Figure 35 This is a schematic diagram of an exploded view of related components shown in an embodiment of the present application;

[0053] Figure 36 A schematic diagram of a carrier structure for an example of this application;

[0054] Figure 37 A schematic diagram of the structure of a cover shell for this application example Figure 1 ;

[0055] Figure 38 A schematic diagram of the structure of a cover shell for this application example Figure 2 ;

[0056] Figure 39 This is a cross-sectional diagram of the connection between the optical fiber connector and the coherent component according to an example of this application;

[0057] Figure 40 This is a schematic diagram of the structure of an optical fiber fixing member used in this application example. Figure 1 ;

[0058] Figure 41 Schematic diagram of the structure of the optical fiber fixing part Figure 2 ;

[0059] Figure 42 This is a schematic diagram of the structure of a coherent optical chip used as an example in this application;

[0060] Figure 43 This is a schematic diagram of the structure of a coherent optical chip used in this application example. Figure 2 ;

[0061] Figure 44 A coherent optical chip surface bumping layout proposed in the examples of this application;

[0062] Figure 45 A schematic diagram of the coherent optical chip structure provided in this application Figure 3 ;

[0063] Figure 46 A schematic diagram of the coherent optical chip structure provided in this application Figure 4 ;

[0064] Figure 47 A schematic diagram of the coherent optical chip structure provided in this application Figure 5 ;

[0065] Figure 48 A schematic diagram of the structure of an unbalanced optical splitter provided in an embodiment of the present application;

[0066] Figure 49 A schematic diagram of a coherent optical chip structure used in this application example Figure 6 ;

[0067] Figure 50 A schematic diagram of a coherent optical chip structure used in this application example Figure 7 . DETAILED DESCRIPTION

[0068] In optical communication systems, light signals are used to carry the information to be transmitted. These signals are then transmitted via information transmission equipment such as optical fibers or optical waveguides to information processing equipment such as computers to complete the information transmission. Because light is passive when transmitted through optical fibers or optical waveguides, low-cost, low-loss information transmission is possible. Furthermore, the signals transmitted by information transmission equipment such as optical fibers or optical waveguides are optical signals, while the signals that information processing equipment such as computers can recognize and process are electrical signals. Therefore, in order to establish an information connection between information transmission equipment such as optical fibers or optical waveguides and information processing equipment such as computers, conversion between electrical and optical signals is necessary.

[0069] In the field of optical communications, optical modules implement the aforementioned conversion between optical and electrical signals. They include both an optical port and an electrical port. The optical port enables optical communication with information transmission equipment such as optical fibers or optical waveguides, while the electrical port enables electrical connection with an optical network terminal (e.g., an optical modem). The electrical connection is primarily used for power supply, I2C signal transmission, data transmission, and grounding. The optical network terminal transmits electrical signals to information processing equipment such as computers via network cables or wireless fidelity (Wi-Fi).

[0070] Figure 1 This is the connection diagram of the optical communication system. Figure 1 As shown, the optical communication system includes a remote server 1000 , a local information processing device 2000 , an optical network terminal 100 , an optical module 200 , an optical fiber 101 and a network cable 103 .

[0071] One end of optical fiber 101 is connected to remote server 1000, and the other end is connected to optical network terminal 100 via optical module 200. Optical fiber itself can support long-distance signal transmission, for example, signal transmission over several kilometers (6 to 8 kilometers). Furthermore, if repeaters are used, theoretically, transmission over an unlimited distance is possible. Therefore, in typical optical communication systems, the distance between remote server 1000 and optical network terminal 100 can typically reach several thousand, tens of kilometers, or even hundreds of kilometers.

[0072] One end of the network cable 103 is connected to the local information processing device 2000, and the other end is connected to the optical network terminal 100. The local information processing device 2000 can be any one or more of the following devices: a router, a switch, a computer, a mobile phone, a tablet computer, a television, etc.

[0073] The physical distance between the remote server 1000 and the optical network terminal 100 is greater than the physical distance between the local information processing device 2000 and the optical network terminal 100. The connection between the local information processing device 2000 and the remote server 1000 is completed by the optical fiber 101 and the network cable 103; and the connection between the optical fiber 101 and the network cable 103 is completed by the optical module 200 and the optical network terminal 100.

[0074] Optical module 200 includes an optical port and an electrical port. The optical port is configured to connect to optical fiber 101, thereby establishing a bidirectional optical signal connection between optical module 200 and optical fiber 101. The electrical port is configured to connect to optical network terminal 100, thereby establishing a bidirectional electrical signal connection between optical module 200 and optical network terminal 100. Optical module 200 performs conversion between optical and electrical signals, thereby establishing an information connection between optical fiber 101 and optical network terminal 100. For example, optical signals from optical fiber 101 are converted to electrical signals by optical module 200 and then input into optical network terminal 100. Similarly, electrical signals from optical network terminal 100 are converted to optical signals by optical module 200 and then input into optical fiber 101. Since optical module 200 is a tool for converting optical and electrical signals and does not process data, the information remains unchanged during the aforementioned optical-to-electrical conversion process.

[0075] The optical network terminal 100 includes a roughly rectangular housing, an optical module interface 102, and a network cable interface 104 disposed on the housing. The optical module interface 102 is configured to connect to the optical module 200, thereby establishing a bidirectional electrical signal connection between the optical network terminal 100 and the optical module 200. The network cable interface 104 is configured to connect to the network cable 103, thereby establishing a bidirectional electrical signal connection between the optical network terminal 100 and the network cable 103. The connection between the optical module 200 and the network cable 103 is established through the optical network terminal 100. For example, the optical network terminal 100 transmits electrical signals from the optical module 200 to the network cable 103, and transmits electrical signals from the network cable 103 to the optical module 200. Therefore, the optical network terminal 100 serves as the host computer of the optical module 200 and can monitor the operation of the optical module 200. In addition to the optical network terminal 100, the host computer of the optical module 200 may also include an optical line terminal (OLT), etc.

[0076] The remote server 1000 establishes a bidirectional signal transmission channel with the local information processing device 2000 through the optical fiber 101 , the optical module 200 , the optical network terminal 100 and the network cable 103 .

[0077] Figure 2 This is a structural diagram of an optical network terminal. In order to clearly show the connection relationship between the optical module 200 and the optical network terminal 100, Figure 2 Only the structure of the optical network terminal 100 related to the optical module 200 is shown. Figure 2 As shown, the optical network terminal 100 further includes a circuit board 105 disposed within the housing, a cage 106 disposed on the surface of the circuit board 105, a heat sink 107 disposed on the cage 106, and an electrical connector disposed within the cage 106. The electrical connector is configured to connect to the electrical port of the optical module 200; the heat sink 107 has protrusions such as fins to increase the heat dissipation area.

[0078] Optical module 200 is inserted into cage 106 of optical network terminal 100. Cage 106 secures optical module 200, and heat generated by optical module 200 is transferred to cage 106 and then dissipated through heat sink 107. After optical module 200 is inserted into cage 106, its electrical port connects to an electrical connector inside cage 106, establishing a bidirectional electrical signal connection between optical module 200 and optical network terminal 100. Furthermore, its optical port connects to optical fiber 101, establishing a bidirectional optical signal connection between optical module 200 and optical fiber 101.

[0079] Figure 3 is a structural diagram of an optical module according to some embodiments. Figure 4 FIG. 4 is a diagram of an exploded structure of an optical module according to some embodiments. Figure 5 FIG. 1 is a structural diagram of an optical module with the housing and unlocking components removed according to some embodiments. Figure 6 FIG is a structural diagram of a fiber optic adapter, a light source, coherent components, and a circuit board according to some embodiments. Figure 3-6 As shown, the optical module 200 includes a shell, a circuit board 300 , a light source 401 , a coherent component 500 , a DSP chip 600 and an optical fiber winding rack 700 disposed in the shell.

[0080] The housing includes an upper housing 201 and a lower housing 202 . The upper housing 201 covers the lower housing 202 to form the housing with two openings. The outer contour of the housing is generally a square.

[0081] In some embodiments of the present disclosure, the lower shell 202 includes a base plate 2021 and two lower side plates 2022 located on both sides of the base plate 2021 and arranged perpendicular to the base plate 2021; the upper shell 201 includes a cover plate 2011, and the cover plate 2011 covers the two lower side plates 2022 of the lower shell 202 to form the above-mentioned shell.

[0082] In some embodiments, the lower shell 202 includes a base plate 2021 and two lower side plates 2022 located on both sides of the base plate 2021 and arranged perpendicularly to the base plate 2021; the upper shell 201 includes a cover plate 2011 and two upper side plates located on both sides of the cover plate 2011 and arranged perpendicularly to the cover plate 2011. The two upper side plates are combined with the two lower side plates 2022 to achieve the upper shell 201 covering the lower shell 202.

[0083] The direction of the line connecting the two openings 204 and 205 may be consistent with the length direction of the optical module 200, or may be inconsistent with the length direction of the optical module 200. For example, the opening 204 is located at the end of the optical module 200 ( Figure 3 The opening 205 is also located at the end of the optical module 200 ( Figure 3 Alternatively, opening 204 is located at the end of optical module 200, while opening 205 is located on the side of optical module 200. Opening 204 is an electrical port, through which the gold finger of circuit board 300 extends and is inserted into a host computer (e.g., optical network terminal 100); opening 205 is an optical port, configured to receive an external optical fiber 101, thereby connecting the external optical fiber 101 to the light source 401 inside optical module 200.

[0084] The combined assembly of the upper and lower housings 201 and 202 facilitates installation of components such as the circuit board 300 and light source 401 within the housing, with the upper and lower housings 201 and 202 providing encapsulation and protection for these components. Furthermore, during assembly of components such as the circuit board 300 and light source 401, the positioning, heat dissipation, and electromagnetic shielding components of these components are easily arranged, facilitating automated production.

[0085] In some embodiments, the upper shell 201 and the lower shell 202 are generally made of metal materials, which are conducive to electromagnetic shielding and heat dissipation.

[0086] In some embodiments, the optical module 200 further includes an unlocking component located outside its housing, and the unlocking component is configured to achieve a fixed connection between the optical module 200 and the host computer, or to release the fixed connection between the optical module 200 and the host computer.

[0087] For example, the unlocking component is located on the outer walls of the two lower side panels 2022 of the lower housing 202 and has a snap-fitting component that mates with the host computer cage (e.g., the cage 106 of the optical network terminal 100). When the optical module 200 is inserted into the host computer cage, the snap-fitting component of the unlocking component secures the optical module 200 in the host computer cage. When the unlocking component is pulled, the snap-fitting component of the unlocking component moves accordingly, thereby changing the connection between the snap-fitting component and the host computer, thereby releasing the snap-fitting relationship between the optical module 200 and the host computer, thereby allowing the optical module 200 to be removed from the host computer cage.

[0088] The circuit board 300 includes circuit traces, electronic components, and chips. The circuit traces connect the electronic components and chips together according to the circuit design to achieve functions such as power supply, electrical signal transmission, and grounding. Electronic components include, for example, capacitors, resistors, transistors, and metal-oxide-semiconductor field-effect transistors (MOSFETs). Chips include, for example, microcontroller units (MCUs), laser driver chips, limiting amplifiers, clock and data recovery (CDR) chips, power management chips, and digital signal processing (DSP) chips.

[0089] The circuit board 300 is generally a rigid circuit board. Due to its relatively hard material, the rigid circuit board can also realize the load-bearing function. For example, the rigid circuit board can stably support the above-mentioned electronic components and chips; when the light source is located on the circuit board, the rigid circuit board can also provide stable support; the rigid circuit board can also be inserted into the electrical connector in the upper computer cage.

[0090] The circuit board 300 also includes a gold finger formed on its end surface. The gold finger is composed of a plurality of independent pins. The circuit board 300 is inserted into the cage 106, and the gold finger is connected to the electrical connector in the cage 106. The gold finger can be provided on the surface of only one side of the circuit board 300 (for example, Figure 4 The gold fingers are configured to establish electrical connections with a host computer to provide power, grounding, I2C signal transmission, data signal transmission, etc.

[0091] Of course, some optical modules also use flexible printed circuits. These are typically used in conjunction with rigid printed circuits to complement them. For example, a flexible printed circuit can be used to connect a rigid printed circuit to a light source.

[0092] The circuit board 300 includes a first circuit board 301, a second circuit board 302 and a third circuit board 303. The first circuit board 301 and the second circuit board 302 are both rigid circuit boards, and the third circuit board 303 is a flexible circuit board. The second circuit board 302 is stacked and placed on one end of the first circuit board 301 close to the light source 401. The second circuit board 302 is located between the first circuit board 301 and the upper shell 201. The first circuit board 301 and the second circuit board 302 are connected through the third circuit board 303.

[0093] Light source 401 is connected to second circuit board 302 and is configured to emit a light beam of a preset specific wavelength. Specifically, light source 401 includes a semiconductor gain chip and a silicon photonics chip. The semiconductor gain chip emits a light beam within a wavelength range, while the silicon photonics chip selects a light beam of a specific wavelength from the light beam within the wavelength range. The silicon photonics chip and the semiconductor gain chip form a resonant cavity, and the light beam of the specific wavelength is reflected back and forth between the silicon photonics chip and the semiconductor gain chip, ensuring stable output of the light beam of the specific wavelength from the semiconductor gain chip.

[0094] The optical module further includes a transmitting optical fiber adapter 800 and a receiving optical fiber adapter 801. The transmitting optical fiber adapter 800 is used to transmit high-speed optical signals, and the receiving optical fiber adapter 801 is used to receive high-speed optical signals.

[0095] Coherent component 500, placed on a circuit board, is used to achieve high-speed optical-to-electrical signal conversion. Specifically, coherent component 500 includes an optical transmission interface, an optical reception interface, and a local oscillator optical interface. A first optical fiber extends from the optical transmission interface, a second optical fiber extends from the optical reception interface, and a third optical fiber extends from the local oscillator optical interface. The optical transmission interface is connected to the transmitting fiber adapter 800, the optical reception interface is connected to the receiving fiber adapter 801, and the local oscillator optical interface is connected to the light source 401. The coherent component is connected to the transmitting fiber adapter, the receiving fiber adapter, and the light source 401 via the optical transmission interface, the optical reception interface, and the local oscillator optical interface, respectively. The coherent component 500 is also connected to the DSP chip 600.

[0096] The narrow-linewidth, high-power laser light emitted by light source 401 is input into coherent component 500 via a local oscillator optical interface. Within coherent component 500, this laser light undergoes beam splitting. One beam, acting as the transmit beam, enters the coherent modulator within the coherent component. Driven by the high-speed electrical signal from DSP chip 600, this optical signal undergoes electrical-to-optical conversion, and the converted high-speed optical signal is output from the module's optical transmit interface. The other beam, acting as the local oscillator beam, undergoes coherent demodulation with the high-speed optical signal input into coherent component 500 from the module's optical receive port. The demodulated electrical signal enters DSP chip 600 for signal processing, completing the optical-to-electrical signal conversion. The narrow-linewidth, high-power laser light is a beam of a specific wavelength.

[0097] Light source 401 also includes an internal fiber optic adapter. A first optical fiber extends from the internal fiber optic adapter, and a local oscillator optical interface extends from the local oscillator optical interface. The first optical fiber and the local oscillator optical fiber are fusion-connected to connect the internal fiber optic adapter to the local oscillator optical interface. A second optical fiber extends from the transmitting fiber optic adapter 800, and the transmitting optical interface extends from the transmitting optical fiber. The second optical fiber and the transmitting optical fiber are fusion-connected to connect the transmitting fiber optic adapter 800 to the transmitting optical interface. A third optical fiber extends from the receiving fiber optic adapter 801, and the receiving optical fiber extends from the receiving optical interface. The third optical fiber and the receiving optical fiber are fusion-connected to connect the receiving fiber optic adapter 801 to the receiving optical interface.

[0098] Because there is a certain failure rate when fusion splicing two optical fibers, a certain amount of fiber length must be reserved to ensure successful splicing of the two fibers. This allows for continued splicing after a splice failure. Furthermore, because the connection point between the first optical fiber and the local oscillator fiber is located near the internal fiber adapter, the connection point between the second optical fiber and the transmitting optical fiber is located near transmitting optical fiber adapter 800, and the connection point between the third optical fiber and the receiving optical fiber is located near receiving optical fiber adapter 801, the lengths of the first optical fiber, local oscillator fiber, transmitting optical fiber, and receiving optical fiber are relatively long.

[0099] The fiber winding rack 700 is used to secure the optical fibers. Specifically, because the circuit board 300 is equipped with high-frequency signal lines and numerous components, the optical fibers cannot be laid directly on the surface of the circuit board 300. Furthermore, because the first optical fiber, local oscillator optical fiber, transmitting optical fiber, and receiving optical fiber are relatively long, to prevent damage to the first optical fiber, local oscillator optical fiber, transmitting optical fiber, and receiving optical fiber caused by the upper housing, a fiber winding rack 700 is provided between the coherent assembly 500 and the upper housing 201 to secure the optical fibers.

[0100] The first optical fiber, local oscillator optical fiber, transmitting optical fiber and receiving optical fiber are all neatly fixed on the optical fiber winding frame 700, which not only avoids the upper shell from damaging the first optical fiber, local oscillator optical fiber, transmitting optical fiber and receiving optical fiber, but also avoids the signal crosstalk problem caused by directly laying the optical fiber on the surface of the circuit board 300.

[0101] Figure 8 FIG. 1 is a structural diagram of a first angle of an optical fiber winding rack according to some embodiments. Figure 9 FIG. 1 is a structural diagram of a second angle of the optical fiber winding rack according to some embodiments. Figure 4-9 It can be seen that in some embodiments, the optical fiber winding rack 700 includes two first support legs 701 and two second support legs 702, the first support legs 701 are engaged with the card interface of the first circuit board 301, and the second support legs 702 are connected to the upper surface of the first circuit board 301, the two first support legs 701 are symmetrically arranged on both sides of the optical fiber winding rack 700, and the two second support legs 702 are symmetrically arranged on both sides of the optical fiber winding rack 700, and the second support legs 702 are closer to the light source 401 than the first support legs 701.

[0102] like Figure 4-9 It can be seen that in some embodiments, the outer surface of the fiber winding rack 700 is provided with a first protrusion 703, a second protrusion 704, a third protrusion 705, a fourth protrusion 706, and a fifth protrusion 707. The first protrusion 703 and the second protrusion 704 are located at the end of the fiber winding rack 700 away from the light source 401, while the third protrusion 705, the fourth protrusion 706, and the fifth protrusion 707 are located at the end of the fiber winding rack 700 closer to the light source 401. First storage grooves are respectively provided between the first protrusion 703, the second protrusion 704, the third protrusion 705, the fourth protrusion 706, and the fifth protrusion 707 and the side edges of the fiber winding rack 700. A second storage groove 708 is provided between the first protrusion 703 and the second protrusion 704. Except for the groove between the first protrusion 703 and the second protrusion 704, any groove between any two protrusions is a first storage groove, and the second storage groove 708 is more recessed than the first storage groove.

[0103] The local oscillator optical fiber, the transmitting optical fiber and the receiving optical fiber all extend from the coherent component 500 through the coherent component 500 and extend into the optical fiber winding rack 700 through the first storage groove between the fourth protrusion 706 and the side of the optical fiber winding rack 700.

[0104] The local oscillator optical fiber passes through the first storage groove between the first protrusion 703 and the side of the optical fiber winding rack 700 → the first storage groove between the second protrusion 704 and the side of the optical fiber winding rack 700 → the first storage groove between the third protrusion 705 and the side of the optical fiber winding rack 700 → the first storage groove between the third protrusion 705 and the fifth protrusion 707 → the first storage groove between the third protrusion 705 and the fourth protrusion 706 → the second storage groove 708 between the second protrusion 704 and the first protrusion 703.

[0105] The local oscillator optical fiber can also be placed after the first storage groove between the third protrusion 705 and the fourth protrusion 706, and then pass through the first storage groove between the second protrusion 704 and the third protrusion 705 → the first storage groove between the third protrusion 705 and the fifth protrusion 707 → the first storage groove between the third protrusion 705 and the fourth protrusion 706 → the first storage groove between the third protrusion 705 and the side of the optical fiber winding frame 700 → the second storage groove 708 between the second protrusion 704 and the first protrusion 703.

[0106] The first optical fiber passes through the first storage slot between the fourth protrusion 706 and the side of the optical fiber winding rack 700 → the first storage slot between the third protrusion 705 and the side of the optical fiber winding rack 700 → the first storage slot between the first protrusion 703 and the side of the optical fiber winding rack 700 → the first storage slot between the second protrusion 704 and the side of the optical fiber winding rack 700 → the first storage slot between the third protrusion 705 and the side of the optical fiber winding rack 700 → the first storage slot between the third protrusion 705 and the fifth protrusion 707 → the third protrusion 708 and the fifth protrusion 709. 05 and the fourth protrusion 706 → the first storage slot between the second protrusion 704 and the third protrusion 705 → the first storage slot between the third protrusion 705 and the fifth protrusion 707 → the first storage slot between the third protrusion 705 and the fourth protrusion 706 → the first storage slot between the third protrusion 705 and the side of the optical fiber winding rack 700 → the first storage slot between the first protrusion 703 and the side of the optical fiber winding rack 700 → the second storage slot 708 between the second protrusion 704 and the first protrusion 703.

[0107] The transmitting optical fiber is fixed in sequence through the first storage groove between the first protrusion 703 and the side of the optical fiber winding rack 700 → the first storage groove between the second protrusion 704 and the side of the optical fiber winding rack 700 → the first storage groove between the third protrusion 705 and the side of the optical fiber winding rack 700, and then extends out of the optical fiber winding rack 700 through the first storage groove between the fifth protrusion 707 and the side of the optical fiber winding rack 700, and is fusion-connected with the second optical fiber near the transmitting optical fiber adapter 800.

[0108] The receiving optical fiber passes through the first storage slot between the first protrusion 703 and the side of the optical fiber winding rack 700 → the first storage slot between the second protrusion 704 and the side of the optical fiber winding rack 700 → the first storage slot between the third protrusion 705 and the side of the optical fiber winding rack 700 → the first storage slot between the fifth protrusion 707 and the third protrusion 705, and is fixed, and then extends out of the optical fiber winding rack 700 through the first storage slot between the fourth protrusion 706 and the fifth protrusion 707, and is fusion-connected with the third optical fiber near the receiving optical fiber adapter 801.

[0109] As can be seen from the above description, the fusion splice point between the first optical fiber and the local oscillator optical fiber is located within the second storage groove 708. To protect the fusion splice point between the first optical fiber and the local oscillator optical fiber, in some embodiments, a protective sleeve is provided within the second storage groove 708. The protective sleeve is used to protect the fusion splice point between the first optical fiber and the local oscillator optical fiber and prevent the fusion splice point between the first optical fiber and the local oscillator optical fiber from breaking.

[0110] Since the fusion splicing point of the first optical fiber and the local oscillator optical fiber is located in the second storage groove 708, in order to increase the number of times the first optical fiber and the local oscillator optical fiber can be fused to ensure successful fusion, the third protrusion 705 is in the shape of a cylinder, and the circumference of the third protrusion 705 is less than (the sum of the lengths of the first storage groove between the first protrusion 703 and the side of the optical fiber winding rack 700, the first storage groove between the second protrusion 704 and the side of the optical fiber winding rack 700, and the first storage groove between the third protrusion 705 and the side of the optical fiber winding rack 700).

[0111] When the optical fiber is not wound along the third protrusion 705, if the fusion splicing between the first optical fiber and the local oscillator optical fiber fails and needs to be re-splice, the length of the first optical fiber or local oscillator optical fiber that needs to be cut is the length of the first optical fiber or local oscillator optical fiber wrapped around the entire fiber winding frame 700. After the optical fiber is wound along the third protrusion 705, if the fusion splicing between the first optical fiber and the local oscillator optical fiber fails and needs to be re-splice, the length of the first optical fiber or local oscillator optical fiber that needs to be cut is the length of the first optical fiber or local oscillator optical fiber wrapped around the third protrusion 705.

[0112] For example, when the third protrusion 705 is not provided, when the first optical fiber and the local oscillator optical fiber fail to be fused and need to be fused again, the length of the first optical fiber that needs to be cut off may be 100 mm; when the third protrusion 705 is provided, when the first optical fiber and the local oscillator optical fiber fail to be fused and need to be fused again, the length of the first optical fiber that needs to be cut off may be 50 mm.

[0113] In order to fix the first optical fiber, local oscillator optical fiber, transmitting optical fiber and receiving optical fiber in the optical fiber winding rack 700, a snap-in strip is provided on the multiple protrusions of the optical fiber winding rack 700 and the side of the optical fiber winding rack 700. One end of the snap-in strip is connected to the surface of the protrusion of the optical fiber winding rack 700, and the other end of the snap-in strip is connected to the surface of the side of the optical fiber winding rack 700.

[0114] The presence of the snap-in strip fixes the first optical fiber, local oscillator optical fiber, transmitting optical fiber and receiving optical fiber in the optical fiber winding rack 700, thereby preventing optical fiber damage caused by the first optical fiber, local oscillator optical fiber, transmitting optical fiber and receiving optical fiber being separated from the optical fiber winding rack 700.

[0115] like Figure 4-9As can be seen, in some embodiments, the inner surface of the fiber winding rack 700 is provided with a third storage groove 709 and a fourth storage groove 710. Both the third storage groove 709 and the fourth storage groove 710 are formed by inward depressions in the inner surface of the fiber winding rack 700, with the third storage groove 709 being more recessed than the fourth storage groove 710. The third storage groove 709 is located at the end of the fiber winding rack 700 closer to the light source 401, and the fourth storage groove 710 is located at the end of the fiber winding rack 700 farther from the light source 401. The third storage groove 709 is used to accommodate the coherent component 500, and the fourth storage groove 710 is used to accommodate the DSP chip 600. The shape of the third storage groove 709 is the same as that of the coherent component 500.

[0116] like Figure 4-9 It can be seen that in some embodiments, the inner surface of the fiber winding rack 700 is further provided with a fifth storage groove 711. The fifth storage groove 711 is closer to the light source 401 than the third storage groove 709. The fifth storage groove 711 is used to accommodate the interface of the coherent component 500. The third storage groove 709 is more recessed than the fifth storage groove 711.

[0117] Figure 10 is a structural diagram of a light source according to some embodiments. Figure 11 is an exploded view of a light source according to some embodiments. Figure 12 is a structural diagram of a first support plate according to some embodiments. Figure 13 4 is a structural diagram of a first angle of a second support plate according to some embodiments. Figure 14 2 is a structural diagram of a second support plate at a second angle according to some embodiments. Figure 15 FIG is a structural diagram of a second circuit board according to some embodiments. Figure 4-15 It can be seen that in some embodiments, the light source assembly 400 includes a light source 401, a first support plate 402, a second support plate 403 and a second circuit board 302. Specifically,

[0118] The side of the light source 401 is provided with multiple metal pins, and the side of the second circuit board 302 is provided with multiple pin pads. The metal pins and the pin pads are provided correspondingly, and the light source 401 and the second circuit board 302 are electrically connected through the metal pins and the pin pads.

[0119] Two first through holes 3022 are provided on the second circuit board 302, and two second through holes 4032 are provided on the second support plate 403. The first through holes 3022 and the second through holes 4032 are provided correspondingly. The first through holes 3022 and the second through holes 4032 are connected by screws to realize the connection between the second circuit board 302 and the second support plate 403.

[0120] The second support plate 403 is further provided with a third through hole 4033, and the first support plate 402 is provided with a fourth through hole 4024. The third through hole 4033 and the fourth through hole 4024 are provided correspondingly. The third through hole 4033 and the fourth through hole 4024 are connected by screws to realize the connection between the first support plate 402 and the second support plate 403.

[0121] A fifth through hole 4031 is also provided on the second support plate 403, and the fifth through hole 4031 is corresponding to the through hole on the cover plate 2011 of the upper shell 201. The fifth through hole 4031 is connected to the through hole on the cover plate 2011 of the upper shell 201 by screws to realize the connection between the second support plate 403 and the upper shell 201.

[0122] The first support plate 402 is also provided with a support plate body 4022, a first support protrusion 4021 and a second support protrusion 4023. The first support protrusion 4021 and the second support protrusion 4023 are both obtained by the upward protrusion of the support plate body 4022. The first support protrusion 4021 is more protruding than the second support protrusion 4023. A fourth through hole 4024 is provided on the first support protrusion 4021, and the second support protrusion 4023 is connected to the lower surface of the light source 401.

[0123] The second supporting protrusion 4023 is a heat dissipation adhesive which not only connects the light source 401 to the first supporting plate 402 but also dissipates the heat of the light source 401 .

[0124] The second support plate 403 is further provided with a sixth storage slot 4034 and a seventh storage slot 4035. The sixth storage slot 4034 and the seventh storage slot 4035 are both formed by inward depressions on the inner surface of the second support plate 403. The sixth storage slot 4034 and the seventh storage slot 4035 are partially connected. The sixth storage slot 4034 is connected to the second circuit board 302, and the seventh storage slot 4035 is connected to the upper surface of the light source 401.

[0125] A first notch 3021 is provided on one side of the second circuit board 302 facing the light source 401. A plurality of pin pads are provided on the side of the first notch 3021. The first support plate 402 and the light source 401 can be placed in the first notch 3021. The length of the first notch 3021 is greater than that of the light source 401.

[0126] like Figure 4-15 It can be seen that in some embodiments, the light source assembly 400 further includes a heat dissipation pad 404. The heat dissipation pad 404 is located between the cover plate 2011 of the upper housing 201 and the second support plate 403, and is used to dissipate the heat of the light source assembly 400 through the upper housing 201 and out of the optical module.

[0127] Current light sources use a combination of semiconductor gain chips and separate filters to achieve wavelength tunability. However, because multiple separate components need to be coupled and packaged within the light source, and these separate components take up a lot of space, the current light sources are too large to meet production requirements.

[0128] To address this issue, some embodiments provide a light source. The light source includes a semiconductor gain chip and a silicon photonics chip. The semiconductor gain chip is configured to emit a light beam within a wavelength range. The silicon photonics chip integrates a wavelength-tunable optical component and a wavelength-locking optical component. The wavelength-tunable optical component is configured to select a specific wavelength beam from the wavelength range emitted by the semiconductor gain chip to achieve wavelength tunability. The wavelength-locking optical component is configured to determine whether the specific wavelength beam deviates from a preset wavelength beam to achieve wavelength locking. If the specific wavelength beam deviates from the preset wavelength beam, the refractive index of the wavelength-tunable optical component is adjusted to ensure that the specific wavelength beam selected by the wavelength-tunable optical component does not deviate from the preset wavelength beam. The semiconductor gain chip and the silicon photonics chip form a resonant cavity. The specific wavelength beam is reflected back and forth between the semiconductor gain chip and the silicon photonics chip, ensuring stable output of the specific wavelength beam from the semiconductor gain chip. The integration of the wavelength-tunable optical component and the wavelength-locking optical component within the silicon photonics chip not only enables wavelength tunability and wavelength locking in the light source but also saves space, resulting in a compact light source that meets production requirements.

[0129] Figure 16 is a structural diagram of a light source according to some embodiments. Figure 17 is an exploded view of a light source according to some embodiments. Figure 18 FIG. 1 is a structural diagram of a light source without the upper cover, optical assembly, and internal fiber optic adapter according to some embodiments. Figure 19 1 is an exploded view of a light source with the upper cover, optical assembly, and internal fiber optic adapter removed according to some embodiments. Figure 20 is a structural diagram of a second fixing frame according to some embodiments. Figure 21 is a structural diagram of a first fixing frame according to some embodiments. Figure 22 is a first cross-sectional view of a light source according to some embodiments. Figure 23 is a second cross-sectional view of a light source according to some embodiments. Figure 4-23As can be seen, in some embodiments, the light source 401 includes a first fixing frame 4011, a second fixing frame 4012, an upper cover 4013, a base 4014, and an internal fiber optic adapter 4016. The first fixing frame 4011 is provided with a second notch 40111 and an insertion hole 40112, respectively located at opposite ends of the first fixing frame 4011. The second fixing frame 4012 is snapped into the second notch 40111 of the first fixing frame 4011, and the internal fiber optic adapter 4016 is placed in the insertion hole 40112. A plurality of metal pins 4015 are provided on a surface of the second fixing frame 4012 that is adjacent to the second circuit board 302. The plurality of metal pins 4015 are soldered to a plurality of pin pads on the second circuit board 302. The first fixing frame 4011, the second fixing frame 4012, the upper cover 4013, and the base 4014 enclose a cavity, within which the optical assembly 405 is disposed.

[0130] like Figure 4-23 As can be seen, in some embodiments, two semiconductor coolers 40141 are disposed on the bottom plate 4014, a ceramic substrate 40142 is disposed on the two semiconductor coolers 40141, and an optical component 405 is disposed on the ceramic substrate 40142. The optical component 405 is placed on the ceramic substrate 40142 to facilitate temperature control of the optical component 405.

[0131] like Figure 4-23 It can be seen that in some embodiments, the optical component 405 includes a semiconductor gain chip 4051, a silicon photonic chip 4052, a first lens 4053, an isolator 4054, a second lens 4055, a semiconductor amplifier chip 4056, a third lens 4057, a beam splitter 4058, a first power monitor 4059 and a fourth lens 4060. Specifically,

[0132] Semiconductor gain chip 4051, located between fourth lens 4060 and first lens 4053, is configured to emit a light beam within a wavelength range. Silicon photonics chip 4052, located on one side of fourth lens 4060, is configured to receive light beams within a wavelength range, filter out a light beam of a specific wavelength from within the wavelength range, and inject the light beam of the specific wavelength into semiconductor gain chip 4051. Silicon photonics chip 4052 and semiconductor gain chip 4051 form a resonant cavity. The light beam of the specific wavelength is reflected back and forth between silicon photonics chip 4052 and semiconductor gain chip 4051, ensuring stable output of the light beam of the specific wavelength from the semiconductor gain chip.

[0133] Silicon photonics chip 4052 is used to select a specific wavelength beam from a range of wavelengths. Specifically, silicon photonics chip 4052 integrates a wavelength-tunable optical component and a wavelength-locking optical component. The wavelength-tunable optical component selects a specific wavelength beam from a range of wavelengths emitted by the semiconductor gain chip to achieve wavelength tunability. The wavelength-locking optical component determines whether the specific wavelength beam deviates from a preset wavelength beam to achieve wavelength locking. If the specific wavelength beam deviates from the preset wavelength beam, the refractive index of the wavelength-tunable optical component is adjusted to ensure that the specific wavelength beam selected by the wavelength-tunable optical component does not deviate from the preset wavelength beam. The semiconductor gain chip and the silicon photonics chip form a resonant cavity. The specific wavelength beam reflects back and forth between the semiconductor gain chip and the silicon photonics chip, ensuring stable output of the specific wavelength beam from the semiconductor gain chip. The integration of the wavelength-tunable and wavelength-locking optical components within the silicon photonics chip not only enables wavelength tunability and wavelength locking functions in the light source, but also saves space, making the light source smaller and meeting production requirements.

[0134] The first lens 4053 is located between the semiconductor gain chip 4051 and the isolator 4054 and is used to collimate the light beam of a specific wavelength. Specifically, the first lens 4053 is a collimating lens that collimates the light beam of a specific wavelength.

[0135] The isolator 4054 is located between the first lens 4053 and the second lens 4055 and is used to prevent the light beam incident on the second lens 4055 from being reflected back into the semiconductor gain chip 4051 , thereby reducing the impact of light path reflection and further reducing the noise level of the light source assembly 400 .

[0136] The second lens 4055 is located between the isolator 4054 and the semiconductor amplifier chip 4056 and is used to converge the light beam of a specific wavelength passing through the isolator 4054 and couple it into the semiconductor amplifier chip 4056. Specifically, the second lens 4055 is a converging lens that converges the light beam of a specific wavelength passing through the isolator 4054 and couples it into the semiconductor amplifier chip 4056.

[0137] The semiconductor amplifier chip 4056 is located between the collimating lens 4057 and the third lens 4057, and is used to amplify the power of the light beam with a specific wavelength to increase the optical power of the light beam with a specific wavelength.

[0138] Since the semiconductor amplifier chip 4056 performs power amplification, the optical power of the light beam of a specific wavelength emitted by the light source provided with the semiconductor amplifier chip 4056 is much higher than the optical power of the light beam emitted by the light source not provided with the semiconductor amplifier chip 4056 .

[0139] The third lens 4057 is located between the semiconductor amplifier chip 4056 and the beam splitter 4058 and is used to collimate the light beam of a specific wavelength. Specifically, the third lens 4057 is a collimating lens that collimates the light beam of a specific wavelength amplified by the semiconductor amplifier chip 4056.

[0140] The beam splitter 4058 is located between the third lens 4057 and the internal optical fiber adapter 4016 and is used to split the specific wavelength light beam into two paths, one path is coupled to the first power monitor 4059 and the other path is coupled to the internal optical fiber adapter 4016.

[0141] A beam splitter is an optical device that can split a single beam into two or more beams, and is typically constructed from a metal or dielectric film. The most common shape is a cube, made from two triangular glass prisms bonded together on a substrate using a polyester, epoxy, or polyurethane adhesive. The thickness of the resin layer is adjusted so that half of the light (of a certain wavelength) incident through one "port" (i.e., a face of the cube) is reflected, while the other half is transmitted due to total internal reflection. Polarizing beam splitters, such as Wollaston prisms, use birefringent materials to separate light into beams of different polarizations. Another design uses a half-silvered mirror, a piece of glass or plastic with a thin, transparent metal coating, now commonly aluminum vapor deposited on it. The thickness of the deposit is controlled so that a portion (usually half) of the light incident at a 45-degree angle and not absorbed by the coating is transmitted, while the rest is reflected.

[0142] First power monitor 4059, located between beam splitter 4058 and second mounting bracket 4012, is used to monitor the optical power of a light beam having a specific wavelength in real time. Specifically, when the optical power of the light beam having a specific wavelength is less than a preset optical power range, the amplification factor of semiconductor amplifier chip 4056 is increased to ensure that the optical power of the light beam having a specific wavelength is within the preset optical power range. When the optical power of the light beam having a specific wavelength is greater than the preset optical power range, the amplification factor of semiconductor amplifier chip 4056 is decreased to ensure that the optical power of the light beam having a specific wavelength is within the preset optical power range.

[0143] In some embodiments, the optical power of the specific wavelength beam is monitored in real time by the first power monitor 4059 and the amplification factor of the semiconductor amplifier chip 4056 is adjusted so that the optical power of the specific wavelength beam emitted by the light source is within a preset optical power range.

[0144] The fourth lens 4060 is located between the semiconductor gain chip 4051 and the silicon photonic chip 4052 and is used to collimate the light beam within a wavelength range output by the semiconductor gain chip 4051 .

[0145] like Figure 4-23As can be seen, in some embodiments, a sixth lens 40161 and an optical window 40162 are disposed within the internal fiber adapter 4016. Optical window 40162 is located closer to the beam splitter 4058 than the sixth lens 40161. A light beam of a specific wavelength is split into two paths by the beam splitter 4058. One path is incident upon the internal fiber adapter 4016 through the optical window 40162, where it is focused and coupled into the optical fiber ferrule of the internal fiber adapter 4016.

[0146] According to the above-described optical assembly 405 and internal fiber optic adapter 4016 , the optical assembly 405 can be classified into the following types.

[0147] Figure 24 FIG. 1 is a light path diagram of a first optical component according to some embodiments. Figure 24 It can be seen that in some embodiments, the optical component 405 includes a semiconductor gain chip 4051, a silicon photonic chip 4052 and a first lens 4053. The semiconductor gain chip 4051 is located between the silicon photonic chip 4052 and the first lens 4053, and the first lens 4053 is located between the semiconductor gain chip 4051 and the internal optical fiber adapter.

[0148] All components in the light source except the silicon photonic chip 4052 are placed on one side of the silicon photonic chip 4052, which effectively saves space in the light source, makes the size of the light source smaller, and makes it easier for the light source to meet production needs.

[0149] Semiconductor gain chip 4051 is used to emit a light beam within a wavelength range. Silicon photonics chip 4052 is used to receive the light beams within the wavelength range and select a light beam of a specific wavelength from within the wavelength range. It is also used to inject the light beam of the specific wavelength into semiconductor gain chip 4051. Semiconductor gain chip 4051 and silicon photonics chip 4052 form a resonant cavity. The light beam of the specific wavelength is reflected back and forth between semiconductor gain chip 4051 and silicon photonics chip 4052, achieving stable output of the light beam of the specific wavelength from the semiconductor gain chip. A first lens 4053 is used to couple the light beam of the specific wavelength emitted by semiconductor gain chip 4051 into an internal fiber optic adapter.

[0150] Semiconductor gain chip 4051 and silicon photonic chip 4052 form a resonant cavity, allowing a specific wavelength beam to reflect back and forth between semiconductor gain chip 4051 and silicon photonic chip 4052, thereby achieving stable output of the specific wavelength beam from the semiconductor gain chip. Specifically, because the semiconductor gain chip is fabricated from III-V group gain materials, it includes two optical waveguide end faces. One end face utilizes a tilted waveguide structure and is coated with an anti-reflection coating to achieve extremely low light field reflectivity. This end face is used for coupling with the input coupler of the silicon photonic chip, facilitating back and forth reflection of the specific wavelength beam between the semiconductor gain chip and the silicon photonic chip. The other end face utilizes a straight waveguide structure and is coated with a reflective coating with a certain reflectivity to achieve both light field reflection and transmission. This allows semiconductor gain chip 4051 to emit the specific wavelength beam when the specific wavelength beam oscillates to a certain level.

[0151] Figure 25 FIG. 1 is a light path diagram of a second optical component according to some embodiments. Figure 25 It can be seen that in some embodiments, the optical assembly 405 further includes an isolator 4054 and a second lens 4055 . The isolator 4054 is located between the first lens 4053 and the second lens 4055 , and the second lens 4055 is located between the isolator 4054 and the internal fiber optic adapter 4016 .

[0152] Figure 26 FIG. 1 is a light path diagram of a third optical component according to some embodiments. Figure 26 It can be seen that in some embodiments, the optical component 405 also includes a semiconductor amplifier chip 4056 and a third lens 4057. The semiconductor amplifier chip 4056 is located between the second lens 4055 and the third lens 4057. The third lens 4057 is located between the semiconductor amplifier chip 4056 and the internal optical fiber adapter 4016.

[0153] Figure 27 FIG. 1 is a light path diagram of a fourth optical component according to some embodiments. Figure 27 It can be seen that in some embodiments, the optical component 405 further includes a beam splitter 4058 and a first power monitor 4059. The beam splitter 4058 is located between the third lens 4057 and the internal fiber adapter 4016, and the first power monitor 4059 is located on one side of the beam splitter 4058.

[0154] Figure 28 FIG. 1 is a light path diagram of a fifth optical component according to some embodiments. Figure 27 It can be seen that, in some embodiments, the optical component 405 further includes a fourth lens 4060 , which is located between the semiconductor gain chip 4051 and the silicon photonic chip 4052 , and the semiconductor gain chip 4051 is located between the fourth lens 4060 and the first lens 4053 .

[0155] Figure 29 is a structural diagram of a first silicon photonic chip according to some embodiments. Figure 30 is a filtering curve diagram of a wavelength sensor according to some embodiments. Figures 29-30 It can be seen that in some embodiments, the first silicon photonic chip includes an input coupler 40521, a directional coupler 40522, a phase modulator 40523, a first power splitter 40524, a first filter 40526, a second filter 40527, a fourth power monitor 40529, a wavelength sensor 405216, a vertical coupler 405217, a fifth power monitor 405218, and a sixth power monitor 405219. The input coupler 40521, the directional coupler 40522, the phase modulator 40523, the first power splitter 40524, the first filter 40526, the second filter 40527, the fourth power monitor 40529, the wavelength sensor 405216, the vertical coupler 405217, the fifth power monitor 405218, and the sixth power monitor 405219 are all formed by the silicon photonic chip using a CMOS process. Specifically,

[0156] The input coupler 40521 is arranged at one end face of the silicon photonic chip 4052 and is used to receive a light beam in a wavelength range emitted by the semiconductor gain chip 4051, and is also used to output the specific wavelength light beam filtered by the silicon photonic chip 4052 to the outside of the silicon photonic chip 4052.

[0157] The specific wavelength light beam is reflected back and forth between the silicon photonic chip 4052 and the semiconductor gain chip 4051, so that the semiconductor gain chip 4051 and the silicon photonic chip 4052 form a resonant cavity, thereby achieving stable output of the specific wavelength light beam by the semiconductor gain chip.

[0158] In some embodiments, the input coupler 40521 adopts an inclined waveguide design, that is, the optical waveguide of the input coupler 40521 is set at a certain angle to the end face of the silicon photonic chip 4052. In this way, when the light beam emitted by the semiconductor gain chip enters the input coupler 40521 from the upper right, part of the light beam may be reflected at the end face of the silicon photonic chip 4052. The reflected light beam will be emitted from the upper right instead of returning to the semiconductor gain chip along the original path, thereby reducing the impact of the light reflection from the end face of the silicon photonic chip on the semiconductor gain chip.

[0159] Because one end face of the semiconductor gain chip utilizes a tilted waveguide structure, the input coupler 40521 is positioned parallel to the tilted waveguide structure of the semiconductor gain chip in the optical path. This ensures that the semiconductor gain chip matches the silicon photonic chip, reduces reflection of the light field from the input coupler 40521, and improves the quality of the light beam. Specifically, the input coupler 40521 can be positioned parallel to the tilted waveguide structure of the semiconductor gain chip in the optical path so that the output angle of the specific wavelength light beam output by the input coupler 40521 is 20°.

[0160] Directional coupler 40522 is located between phase modulator 40523 and input coupler 40521 and is used to split the light beam. Specifically, a first end of directional coupler 40522 is connected to input coupler 40521 via an optical waveguide, a second end of directional coupler 40522 is connected to phase modulator 40523 via an optical waveguide, a third end of directional coupler 40522 is connected to fourth power monitor 40529 via an optical waveguide, and a fourth end of directional coupler 40522 is connected to a first end of wavelength sensor 405216 via an optical waveguide. The directional coupler 40522 splits the input specific wavelength light beam into three light beams. The first light beam is transmitted to the input coupler 40521 via the first optical waveguide, and then output to the outside of the silicon photonic chip 4052 via the input coupler 40521; the second light beam is transmitted to the fourth power monitor 40529 via the optical waveguide, so that the fourth power monitor 40529 can monitor the optical power of the specific wavelength light beam; the third light beam is transmitted to the wavelength sensor 405216 via the optical waveguide for wavelength locking.

[0161] Phase modulator 40523, located between directional coupler 40522 and first power splitter 40524, is used to adjust the wavelength of the light beam supported by the resonant cavity so that the specific wavelength light beam filtered by first filter 40526 and second filter 40527 coincides with the light beam within the resonant cavity. Specifically, the first end of phase modulator 40523 is connected to the second end of directional coupler 40522 via an optical waveguide, and the second end of phase modulator 40523 is connected to first power splitter 40524 via an optical waveguide. Phase modulator 40523 is equipped with a heater. By changing the heater, the cavity length of phase modulator 40523 is changed, thereby changing the cavity length of the resonant cavity, so that the light beam of a certain wavelength supported by the resonant cavity coincides with the specific wavelength light beam filtered by the two filters.

[0162] The first power splitter 40524 is located between the first filter 40526 and the phase modulator 40523 and is used to split the light beam and also to combine the light beams.

[0163] The first end of the first power divider 40524 is connected to the second end of the phase modulator 40523 through an optical waveguide, the second end of the first power divider 40524 is connected to the first filter 40526 through an optical waveguide, and the third end of the first power divider 40524 is connected to the second filter 40527 through an optical waveguide.

[0164] A power splitter generally refers to a power distributor. A power splitter is a device that splits one input signal into two or more equal or unequal outputs. It can also combine multiple signal energies into one output, in which case it is also called a combiner.

[0165] The first power splitter 40524 can split the light beam inputted by the phase modulator 40523 into two light beams. One light beam first passes through the first filter 40526 and then through the second filter 40527, while the other light beam first passes through the second filter 40527 and then through the first filter 40526. The first power splitter 40524 can also combine a light beam of a specific wavelength filtered out by the first filter 40526 and then through the second filter 40527 with a light beam of a specific wavelength filtered out by the second filter 40527 and then through the first filter 40526, into a single light beam of a specific wavelength.

[0166] The first power splitter 40524 has a splitting ratio of 50%:50%. Specifically, the first power splitter 40524 splits a light beam into two light beams at a ratio of 50%:50%. These two light beams are filtered by the first filter 40526 and the second filter 40527 before returning to the first power splitter 40524. Based on the principle of optical path reversibility, theoretically, other losses, except for those caused by the first filter 40526, the second filter 40527, and the optical waveguide, are zero. The first power splitter 40524 splits a light beam into two light beams at a ratio of 20%:80%. These two light beams are filtered by the first filter 40526 and the second filter 40527 before returning to the first power splitter 40524. Based on the principle of optical path reversibility, theoretically, other losses, except for those caused by the first filter 40526, the second filter 40527, and the optical waveguide, are greater than zero. Therefore, in order to minimize beam loss, in some embodiments, the splitting ratio of the first power divider 40524 is 50%:50%.

[0167] First filter 40526 cooperates with second filter 40527 to filter a specific wavelength beam from a wavelength range of light emitted by semiconductor gain chip 4051. Specifically, the first filter is coupled to the power splitter via a first straight optical waveguide, the second filter is coupled to the first filter via a second straight optical waveguide, and the second filter is coupled to the first power splitter via a third straight optical waveguide. Both first filter 40526 and second filter 40527 are microring structures, but have different circumferences. This results in different wavelengths of the light beams filtered by first filter 40526 and second filter 40527. Due to the vernier effect, the light beam filtered by silicon photonic chip 4052 is a specific wavelength beam only when the wavelengths of the light beams filtered by first filter 40526 and second filter 40527 coincide.

[0168] The second end of the first power divider 40524 is connected to the first straight optical waveguide, the first straight optical waveguide is coupled to the first filter 40526, the first filter 40526 and the second filter 40527 are coupled to the second straight optical waveguide respectively, the second filter 40527 is coupled to the third straight optical waveguide, and the second end of the first power divider 40524 is connected to the third straight optical waveguide.

[0169] The process of the first filter 40526 and the second filter 40527 screening a light beam of a specific wavelength is as follows:

[0170] A light beam within a wavelength range is incident upon the input end of the first straight waveguide (near the first power divider 40524). When the light beam reaches the first coupling region between the first straight waveguide and the first filter 40526, a portion of the light beam is coupled into the first filter 40526, while the remaining portion of the light beam is output from the output end of the first straight waveguide (away from the first power divider 40524). After entering the first filter 40526 and propagating through the second coupling region formed by the second straight waveguide and the first filter 40526, a portion of the light beam is coupled into the second straight waveguide, while the remaining portion of the light beam continues to propagate through the first filter 40526. When the light beam propagating through the first filter 40526 meets the resonance condition mλ = nl of the first filter 40526, resonance occurs, resulting in coherence enhancement. The optical power of the light beam received by the second straight waveguide from the first filter 40526 also increases, while the light beam that does not meet the resonance condition is output from the output end of the first straight waveguide. Where λ is the wavelength of the light beam, l is the circumference of the first filter, n is the effective refractive index of the first filter, and m is a positive integer. In other words, only light beams that meet the resonance condition of the first filter 40526 can be filtered out by the first filter 40526 and coupled to the second straight optical waveguide.

[0171] When the light beam reaches the third coupling region between the second straight optical waveguide and the second filter 40527, part of the light beam is coupled into the second filter 40527, while the remaining part of the light beam is output from the second output end of the second straight optical waveguide. After entering the second filter 40527, the light beam passes through the fourth coupling region formed by the third straight optical waveguide and the second filter 40527, part of the light beam is coupled into the third straight optical waveguide, while the remaining part of the light beam continues to propagate through the second filter 40527. When the light beam propagating through the second filter 40527 meets the resonance condition mλ = nl of the second filter 405276, resonance occurs, resulting in coherence enhancement. The optical power of the light beam received from the second filter 40527 by the third straight optical waveguide also increases, while light that does not meet the resonance condition is output from the second output end of the second straight optical waveguide. Here, λ is the wavelength of the light beam, l is the circumference of the second filter, n is the effective refractive index of the second filter, and m is a positive integer. In other words, only light beams that meet the resonance condition of the second filter 40527 are filtered by the second filter 40527 and coupled to the third straight optical waveguide. At this time, the light beam received by the third straight optical waveguide is a light beam with a specific wavelength.

[0172] The above is the process of filtering out a light beam of a specific wavelength by first passing through the first filter 40526 and then through the second filter 40527. Similarly, the process of filtering out a light beam of a specific wavelength by first passing through the second filter 40527 and then through the first filter 40526 is as follows:

[0173] A light beam within a wavelength range is incident upon the input end of the third straight optical waveguide (near the first power divider 40524). When the light beam reaches the fourth coupling region between the third straight optical waveguide and the second filter 40527, a portion of the light beam is coupled into the second filter 40527, while the remaining portion of the light beam is output from the output end of the third straight optical waveguide (away from the first power divider 40524). After entering the second filter 40527 and propagating through the third coupling region formed by the second straight optical waveguide and the second filter 40527, a portion of the light beam is coupled into the second straight optical waveguide, while the remaining portion of the light beam continues to propagate through the second filter 40527. When the light beam propagating through the second filter 40527 meets the resonance condition mλ = nl of the second filter 40527, resonance occurs, resulting in coherence enhancement. The optical power of the light beam received by the second straight optical waveguide from the second filter 40527 also increases, while light that does not meet the resonance condition is output from the output end of the third straight optical waveguide.

[0174] When the light beam reaches the second coupling region between the second straight optical waveguide and the first filter 40526, a portion of the light beam is coupled into the first filter 40526, while the remaining portion of the light beam is output from the first output end of the second straight optical waveguide. After entering the first filter 40526 and passing through the first coupling region formed by the first straight optical waveguide and the first filter 40526, a portion of the light beam is coupled into the first straight optical waveguide, while the remaining portion of the light beam continues to propagate through the first filter 40526. When the light beam propagating through the first filter 40526 meets the resonance condition mλ = nl of the first filter 40526, resonance occurs, resulting in coherence enhancement. The optical power of the light beam received by the first straight optical waveguide from the first filter 40526 also increases, while light that does not meet the resonance condition is output from the first output end of the second straight optical waveguide. At this point, the light beam received by the first straight optical waveguide is a light beam of a specific wavelength.

[0175] Both first filter 40526 and second filter 40527 have microring structures, but they have different circumferences. Based on the resonance conditions, the wavelengths of the light beams filtered by first filter 40526 and second filter 40527 are different. Due to the Vernier effect, the light beam filtered by silicon photonic chip 4052 is a light beam of a specific wavelength only when the light beams filtered by first filter 40526 and second filter 40527 overlap.

[0176] The first filter 40526 , the second filter 40527 and the phase modulator 40523 constitute a wavelength tunable optical component. The wavelength tunable optical component is used to filter out a specific wavelength light beam from a wavelength range of the light beam emitted by the semiconductor gain chip 4051 .

[0177] First filter 40526 and second filter 40527 are capable of filtering a specific wavelength from a wavelength range of light emitted by semiconductor gain chip 4051. This wavelength is determined by the properties of first filter 40526 and second filter 40527. However, the resonant cavity formed by the semiconductor gain chip and the silicon photonic chip selectively supports multiple light beams of different wavelengths based on its cavity structure. The multiple wavelengths supported by the resonant cavity and the light beams filtered by the two filters do not necessarily overlap. If the multiple wavelengths supported by the resonant cavity do not overlap with the specific wavelengths filtered by the two filters, the refractive index of the phase modulator can be changed to change the cavity length of the phase modulator, thereby changing the cavity length of the resonant cavity. This allows the light beam of a specific wavelength supported by the resonant cavity to overlap with the specific wavelength, thereby causing the resonant cavity to emit the specific wavelength.

[0178] Fourth power monitor 40529 is configured to monitor the optical power of a light beam at a specific wavelength, thereby monitoring the optical power of the light beam at a specific wavelength coupled to semiconductor gain chip 4051. Specifically, fourth power monitor 40529 is connected to the third end of directional coupler 40522 via an optical waveguide. Fourth power monitor 40529 monitors the optical power of the second light beam split by directional coupler 40522, thereby monitoring the optical power of the first light beam split by directional coupler 40522 and input to semiconductor gain chip 4051.

[0179] When semiconductor gain chip 4051 couples the optical power of a specific wavelength beam, the photocurrent flowing through fourth power monitor 40529 is monitored in real time. By applying a fixed current to semiconductor gain chip 4051 and adjusting the relative positions of semiconductor gain chip 4051 and silicon photonic chip 4052, the photocurrent flowing through fourth power monitor 40529 varies with the coupling position. The position with the highest photocurrent corresponds to the position with the highest coupled optical power.

[0180] The wavelength sensor 405216 has a first end connected to the vertical coupler 405217 via an optical waveguide, and a second end connected to the fifth power monitor 405218 and the sixth power monitor 405219 via optical waveguides, respectively, for measuring whether a specific wavelength light beam changes, that is, whether the specific wavelength light beam deviates from a preset wavelength light beam.

[0181] Wavelength sensor 405216 is temperature-insensitive. When the temperature of the silicon photonic chip changes, the filter curve of wavelength sensor 405216 remains essentially unchanged. Therefore, wavelength sensor 405216 can be used as a device to measure changes in a specific wavelength beam.

[0182] The fifth power monitor 405218 and the sixth power monitor 405219 are respectively used to monitor the optical power of the output light beam at the output end of the wavelength sensor 405216.

[0183] The wavelength sensor 405216, the fifth power monitor 405218 and the sixth power monitor 405219 form a wavelength locking optical component to achieve wavelength locking. Specifically, the optical power monitored by the fifth power monitor 405218 is recorded as P x The optical power monitored by the sixth power monitor 405219 is recorded as P y , according to P x / P y To characterize the wavelength change direction of a specific wavelength beam. x / P y The wavelength deviation direction of the specific wavelength light beam is known, and the wavelength tunable optical component in the silicon photonic chip 4052 is adjusted to make P x / P yRestore to the default value. x / P y When the value is restored to the preset value, the selected specific wavelength beam is the preset wavelength beam.

[0184] According to P x / P y To characterize the wavelength change direction of a light beam of a specific wavelength. Specifically, according to the filtering curve of wavelength sensor 405216, it can be seen that the optical power (light intensity, equal to the optical power per unit area, referred to as intensity) of the output light beam at the output end of wavelength sensor 405216 is in a cosine function relationship with the wavelength, that is, the optical power monitored by the fifth power monitor 405218 and the sixth power monitor 405219 are both cosine functions, and the two are in a complementary relationship. Since the optical power monitored by the fifth power monitor 405218 and the sixth power monitor 405219 are both cosine functions, and the two are in a complementary relationship, and wavelength sensor 405216 is temperature-insensitive, then it can be calculated based on P x / P y To characterize the direction of wavelength change of a light beam with a specific wavelength.

[0185] For example, the wavelength of the preset wavelength beam is set to 1549.7. When the wavelength of the input beam at the input end of the wavelength sensor 405216 is 1549.7nm, P x / P y =1; when the wavelength of the input beam at the input end of wavelength sensor 405216 is 1549.8nm, P x / P y It is much larger than 1, indicating that 1549.8nm deviates from the preset wavelength.

[0186] In some embodiments, the x / (P x +P y ) to characterize the wavelength change direction of a specific wavelength beam; or, according to P y / (P x +P y ) is used to characterize the wavelength change direction of a light beam with a specific wavelength.

[0187] According to P x / P y The wavelength deviation direction of the specific wavelength light beam is known, and the wavelength tunable optical component in the silicon photonic chip 4052 is adjusted to make P x / P y Specifically, the first filter 40526 and the second filter 40527 are both provided with heaters. x / P yWhen deviating from the preset value, the first filter 40526 or the second filter 40527, or the heaters of the first filter 40526 and the second filter 40527 are adjusted to change the refractive index of the filter, thereby changing the wavelength of the light beam passing through the filter, so that the light beam filtered out by the wavelength-tunable optical component is a specific wavelength light beam.

[0188] The vertical coupler 405217 is used to couple the light beam outside the silicon photonic chip 4052 into the silicon photonic chip 4052 to test the filtering characteristics of the wavelength sensor 405216. Specifically, due to the material and process errors in the actual processing of the silicon photonic chip, it is easy to cause the phase of the wavelength sensor 405216 to deviate, thereby changing the filtering characteristics of the wavelength sensor 405216. When the filtering characteristics of the wavelength sensor 405216 change, it is considered that the specific wavelength light beam is not the preset wavelength light beam. In order to avoid this problem, it is necessary to test the filtering characteristics of the wavelength sensor 405216 before using the optical module. The preset wavelength light beam outside the silicon photonic chip 4052 is coupled into the silicon photonic chip 4052 through the vertical coupler 405217, and is incident on the wavelength sensor 405216 through the optical waveguide between the vertical coupler 405217 and the wavelength sensor 405216. When P x / P y When the wavelength sensor 405216 deviates from the preset value, the phase difference of the wavelength sensor 405216 is changed by adjusting the heater on one of the modulation arms of the wavelength sensor 405216 to restore the filtering characteristics of the wavelength sensor 405216.

[0189] like Figure 29 As shown, the wavelength sensor 405216 includes a first optical splitter 4052161, a first modulation arm 4052163, a second modulation arm 4052164 and a second optical splitter 4052162. Specifically,

[0190] The first optical splitter 4052161 has a first end connected to the fourth end of the directional coupler 40522 and the vertical coupler 405217 via optical waveguides, and a second end connected to the first end of the first modulation arm 4052163 and the first end of the second modulation arm 4052164. The first optical splitter 4052161 is configured to split the light beam transmitted by the directional coupler 40522 or the vertical coupler 405217 into two beams, and transmit the two light beams to the first modulation arm 4052163 and the second modulation arm 4052164, respectively. Specifically,

[0191] The first end of the first optical splitter 4052161 includes a first input port and a second input port, the second end of the first optical splitter 4052161 includes a first output port and a second output port, the first input port is connected to the fourth end of the directional coupler 40522 through an optical waveguide, the second input port is connected to the vertical coupler 405217 through an optical waveguide, the first output port is connected to the first end of the first modulation arm 4052163, and the second output port is connected to the first end of the second modulation arm 4052164.

[0192] The second optical splitter 4052162 has a first end connected to the second end of the first modulation arm 4052163 and the second end of the second modulation arm 4052164, and a second end connected to the fifth power monitor 405218 and the sixth power monitor 405219 via optical waveguides. The second optical splitter 4052162 is configured to couple the light beams from the first modulation arm 4052163 and the second modulation arm 4052164 into one light beam, and to split the one light beam into two light beams. One light beam enters the fifth power monitor 405218 via the optical waveguide to be monitored by the fifth power monitor 405218, while the other light beam enters the sixth power monitor 405219 via the optical waveguide to be monitored by the sixth power monitor 405219. Specifically,

[0193] The first end of the second splitter 4052162 includes a third input port and a fourth input port, the second end of the second splitter 4052162 includes a third output port and a fourth output port, the third input port is connected to the second end of the first modulation arm 4052163, the fourth input port is connected to the second end of the second modulation arm 4052164, the third output port is connected to the fifth power monitor 405218 through an optical waveguide, and the fourth output port is connected to the sixth power monitor 405219 through an optical waveguide.

[0194] The first optical splitter 4052161 and the second optical splitter 4052162 both utilize the interference principle to realize light splitting and light combining.

[0195] The first beam splitter 4052161 and the second beam splitter 4052162 have equal splitting ratios. Specifically, when the splitting ratios of the first beam splitter 4052161 and the second beam splitter 4052162 differ significantly, beam loss can easily occur. To reduce beam loss, in some embodiments, the splitting ratios of the first beam splitter 4052161 and the second beam splitter 4052162 are designed to be approximately equal. However, to further reduce beam loss, the splitting ratios of the first beam splitter 4052161 and the second beam splitter 4052162 can be designed to be equal, with the splitting ratios of the first beam splitter 4052161 being 50%:50% and the splitting ratios of the second beam splitter 4052162 also being 50%:50%.

[0196] At the same time, only one of the light beams transmitted by the directional coupler 40522 and the vertical coupler 405217 is coupled to the first optical splitter 4052161. For example, at time T1, the light beam transmitted by the directional coupler 40522 is coupled to the first optical splitter 4052161; at time T2, the light beam transmitted by the vertical coupler 405217 is coupled to the first optical splitter 4052161.

[0197] The first modulation arm 4052163 has a first end connected to the second end of the first optical splitter 4052161 , and a second end connected to the first end of the second optical splitter 4052162 .

[0198] The second modulation arm 4052164 has a first end connected to the second end of the first optical splitter 4052161 , and a second end connected to the first end of the second optical splitter 4052162 .

[0199] Among them, the first modulation arm 4052163 is a silicon waveguide, and the second modulation arm 4052164 is a silicon waveguide + silicon nitride waveguide + silicon waveguide.

[0200] The wavelength sensor 405216 has a temperature-insensitive characteristic. Specifically,

[0201] In a wavelength sensor based on the Mach-Zehnder interferometer principle, the waveform of the output intensity of the output beam at the output end varying with the wavelength of the input beam at the input end is related to the refractive index and length of the upper and lower modulation arms. The difference between the refractive index and the length of the modulation arms in the two modulation arms determines the wavelength position of the input beam. Therefore, as long as the waveguide design ensures that the difference between the product of the two modulation arms (the product of the refractive index and the modulation arm length) remains unchanged at different temperatures, the waveform of the output intensity of the output beam at the output end varying with the wavelength of the input beam at the input end can be guaranteed to remain unchanged at different temperatures, thereby achieving the temperature-insensitive characteristic of the input beam wavelength.

[0202] Since the first modulation arm 4052164 is a silicon waveguide and the second modulation arm 4052164 is a silicon waveguide + silicon nitride waveguide + silicon waveguide, it is only necessary to adjust the lengths of the first modulation arm 4052164 and the second modulation arm 4052164 so that the difference between the product of the length and the refractive index of the first modulation arm 4052164 and the product of the length and the refractive index of the second modulation arm 4052164 remains unchanged, thereby achieving the wavelength insensitivity to temperature.

[0203] Since the first end of the second modulator arm 4052164 is a silicon waveguide, the second end of the second modulator arm 4052164 is a silicon waveguide, and the silicon nitride waveguide is located between the first and second ends of the second modulator arm 4052164, in order to ensure smooth transmission of a light beam of a specific wavelength between waveguides made of two different materials, two waveguide converters are provided on the second modulator arm 4052164, and the two waveguide converters are respectively located between the silicon waveguide and the silicon nitride waveguide.

[0204] Since two waveguide converters are provided on the second modulation arm 4052164 , in order to eliminate the influence of the two waveguide converters on the second modulation arm 4052164 , two waveguide converters are correspondingly provided on the first modulation arm 4052163 .

[0205] like Figure 29 In some embodiments, the first silicon photonic chip further includes multiple absorbers, which are used to absorb the optical power of unwanted light beams to prevent reflection and stray light. Specifically, the first silicon photonic chip includes a first absorber 405211, a second absorber 405212, a third absorber 405213, and a fourth absorber 405214.

[0206] The first power divider 40524 is connected to the input end of the first straight optical waveguide, the first absorber 405211 is connected to the output end of the first straight optical waveguide, the second absorber 405212 is connected to the first output end of the second straight optical waveguide, the third absorber 405213 is connected to the second output end of the second straight optical waveguide, the first power divider 40524 is connected to the input end of the third straight optical waveguide, and the fourth absorber 40214 is connected to the output end of the third straight optical waveguide.

[0207] The first absorber 405211 is configured to absorb the light beams in the first straight optical waveguide other than those that pass through the first filter 40526 and the second filter 40527. The second absorber 405212 and the third absorber 405213 are configured to absorb the light beams in the second straight optical waveguide other than those that pass through the first filter 40526 and the second filter 40527. The fourth absorber 405214 is configured to absorb the light beams in the third straight optical waveguide other than those that pass through the first filter 40526 and the second filter 40527.

[0208] In some embodiments, a light source includes a semiconductor gain chip and a silicon photonics chip. The silicon photonics chip is configured to receive a light beam within a wavelength range emitted by the semiconductor gain chip, filter a light beam of a specific wavelength from the light beam, and transmit the light beam of the specific wavelength to the semiconductor gain chip. The semiconductor gain chip and the silicon photonics chip form a resonant cavity. The light beam of the specific wavelength is reflected back and forth between the semiconductor gain chip and the silicon photonics chip, causing the resonant cavity to emit a light beam of the specific wavelength. The silicon photonics chip includes an input coupler, a directional coupler, a wavelength-tunable optical component, a wavelength sensor, a fifth power monitor, and a sixth power monitor. The directional coupler is connected to the input coupler, the wavelength-tunable optical component, and the wavelength sensor via optical waveguides, respectively. The wavelength sensor is also connected to the fifth power monitor and the sixth power monitor via optical waveguides. The input coupler, directional coupler, the wavelength-tunable optical component, the wavelength sensor, the fifth power monitor, and the sixth power monitor are integrated on the silicon photonics chip, saving space and making the light source smaller to meet production requirements. The input coupler is configured to receive a light beam within a wavelength range emitted by the semiconductor gain chip and transmit a light beam of a specific wavelength to the semiconductor gain chip. The directional coupler is configured to split the light beam of the specific wavelength into two beams. The wavelength-tunable optical component is used to filter out a specific wavelength beam from a light beam within a wavelength range to achieve a wavelength-tunable function. The wavelength sensor, the fifth power monitor, and the sixth power monitor constitute a wavelength-locking optical component. The wavelength-locking optical component characterizes whether the specific wavelength beam deviates from the preset wavelength beam based on the ratio of the optical power of the fifth power monitor to the optical power of the sixth power monitor to achieve a wavelength-locking function. When the specific wavelength beam deviates from the preset wavelength beam, the wavelength-tunable optical component is adjusted to prevent the specific wavelength beam from deviating from the preset wavelength beam. In the present application, the input coupler, the directional coupler, the wavelength-tunable optical component, and the wavelength-locking optical component are integrated on a silicon photonic chip, which saves space and makes the size of the light source smaller to meet production requirements; the wavelength-tunable optical component and the wavelength-locking optical component cooperate to ensure that the specific wavelength beam output by the light source does not deviate from the preset wavelength beam.

[0209] To address the large size of current light sources, some embodiments propose another light source. This light source includes a semiconductor gain chip, a silicon photonics chip, a wavelength calibration component, and a second power monitor. The semiconductor gain chip is configured to emit a light beam within a wavelength range. The silicon photonics chip integrates a wavelength-tunable optical component, which is used to select a specific wavelength beam from the light beam within the wavelength range emitted by the semiconductor gain chip to achieve wavelength tunability. The semiconductor gain chip and the silicon photonics chip form a resonant cavity. The specific wavelength beam is reflected back and forth between the semiconductor gain chip and the silicon photonics chip, ensuring stable output of the specific wavelength beam from the semiconductor gain chip. A power monitor, wavelength calibration component, and second power monitor within the silicon photonics chip form a wavelength-locking optical component. This wavelength-locking optical component is used to determine whether the specific wavelength beam deviates from a preset wavelength beam, thereby achieving wavelength locking. If the specific wavelength beam deviates from the preset wavelength beam, the refractive index of the wavelength-tunable optical component is adjusted to ensure that the specific wavelength beam selected by the wavelength-tunable optical component does not deviate from the preset wavelength beam. The semiconductor gain chip and the silicon photonics chip form a resonant cavity. A beam of light at a specific wavelength bounces back and forth between the two, ensuring stable output from the semiconductor gain chip. The silicon photonics chip integrates a wavelength-tunable optical component. A power monitor, wavelength calibration component, and a second power monitor within the chip form a wavelength-locking optical component. This not only enables wavelength tunability and wavelength locking, but also saves space, allowing the light source to be smaller to meet production requirements.

[0210] like Figure 17 、 22 As shown in Figure 23, in some embodiments, the optical assembly 405 may include, in addition to the semiconductor gain chip 4051, the silicon photonic chip 4052, the first lens 4053, the isolator 4054, the second lens 4055, the semiconductor amplifier chip 4056, the third lens 4057, the beam splitter 4058, the first power monitor 4059, and the fourth lens 4060, a fifth lens, a wavelength calibration component, and a second power monitor. Specifically,

[0211] The semiconductor gain chip 4051, the first lens 4053, the isolator 4054, the second lens 4055, the semiconductor amplifier chip 4056, the third lens 4057, the beam splitter 4058, the first power monitor 4059 and the fourth lens 4060 have been introduced and will not be repeated here.

[0212] However, the silicon photonic chip 4052 is only equipped with wavelength-tunable optical components, but no wavelength-locking optical components. Therefore, the silicon photonic chip 4052 can only achieve wavelength tunability, but not wavelength locking.

[0213] To achieve wavelength locking, in some embodiments, the optical assembly 405 also needs to include a fifth lens, a wavelength calibration component, and a second power monitor.

[0214] The fifth lens, located on the same side of silicon photonics chip 4052 as fourth lens 4060 and between silicon photonics chip 4052 and the wavelength calibration component, is used to couple the light beam of a specific wavelength emitted by the silicon photonics chip to the wavelength calibration component. Specifically, the fifth lens is a focusing lens that focuses the light beam of a specific wavelength and couples it to the wavelength calibration component.

[0215] The wavelength calibration component is located between the fifth lens and the second power monitor.

[0216] The second power monitor is used to monitor the optical power of the specific wavelength light beam passing through the wavelength calibration component.

[0217] A power monitor, a wavelength calibration component, and a second power monitor within the silicon photonic chip 4052 form a wavelength locking optical component. The wavelength locking optical component is used to determine whether a specific wavelength beam deviates from a preset wavelength beam, thereby achieving a wavelength locking function.

[0218] Figure 31 FIG. 1 is a light path diagram of a sixth optical component according to some embodiments. Figure 31 It can be seen that, in some embodiments, the optical component 405 includes a semiconductor gain chip 4051 , a silicon photonic chip 4052 , a first lens 4053 , a fifth lens 4061 , a wavelength calibration component 4062 and a second power monitor 4063 .

[0219] The semiconductor gain chip 4051 is located between the silicon photonics chip 4052 and the first lens 4053. The first lens 4053 is located between the semiconductor gain chip 4051 and the internal fiber adapter. The fifth lens 4061 is located between the silicon photonics chip 4052 and the wavelength calibration component 4062. The wavelength calibration component 4062 is located between the fifth lens 4061 and the second power monitor 4063.

[0220] All components in the light source except the silicon photonic chip 4052 are placed on the same side of the silicon photonic chip 4052, which effectively saves space in the light source, makes the size of the light source smaller, and makes it easier for the light source to meet production needs.

[0221] Semiconductor gain chip 4051 is used to emit a light beam within a wavelength range. Silicon photonic chip 4052 is used to receive light beams within a wavelength range and select a light beam of a specific wavelength from within the wavelength range. It is also used to direct the light beam of the specific wavelength into semiconductor gain chip 4051 and fifth lens 4061. First lens 4053 is used to couple the light beam of the specific wavelength emitted by semiconductor gain chip 4051 into an internal fiber adapter. Fifth lens 4061 is used to couple the light beam of the specific wavelength output by silicon photonic chip 4052 into wavelength calibration component 4062. Second power monitor 4063 is used to monitor the optical power of the light beam of the specific wavelength passing through wavelength calibration component 4062. The direction of wavelength change of the light beam of the specific wavelength is characterized by the ratio (i.e., P1 / P0) of the optical power (denoted as P0) monitored by a power monitor for monitoring the light beam of the specific wavelength in silicon photonic chip 4052 to the optical power (denoted as P1) monitored by second power monitor 4063.

[0222] A light beam within a wavelength range emitted by the semiconductor gain chip 4051 is incident on the silicon photonic chip 4052. The silicon photonic chip 4052 selects a light beam with a specific wavelength from the light beams within the wavelength range. The light beam with the specific wavelength is incident on the fifth lens 4061. The fifth lens 4061 couples the light beam with the specific wavelength output by the silicon photonic chip 4052 to the wavelength calibration component 4062. The second power monitor 4063 monitors the optical power of the light beam with the specific wavelength passing through the wavelength calibration component 4062.

[0223] A power monitor in silicon photonics chip 4052, wavelength calibration component 4061, and second power monitor 4063 form a wavelength-locking optical assembly. This assembly detects whether a specific wavelength beam deviates from a preset wavelength beam based on the ratio of the optical power of second power monitor 4063 to the optical power of a power monitor in silicon photonics chip 4052, thereby achieving wavelength locking.

[0224] When the wavelength of the selected specific wavelength beam deviates from the wavelength of the preset wavelength beam, the optical power of the second power monitor 4063 changes, causing P1 / P0 to deviate from the preset value. When the wavelength of the selected specific wavelength beam deviates from the wavelength of the preset beam, the optical power input from the wavelength calibration component into the second power monitor 4063 changes, causing P1 / P0 to deviate from the preset value. The increase or decrease in P1 / P0 reflects the direction of the wavelength shift of the specific wavelength beam, that is, whether the wavelength of the specific wavelength beam is shifting toward longer wavelengths or shorter wavelengths. Once the direction of the shift is determined, P1 / P0 can be restored to the preset value by adjusting the components within the silicon photonic chip 4052. When P1 / P0 returns to the preset value, the wavelength of the selected specific wavelength beam is the wavelength of the preset wavelength beam. The preset wavelength beam is a local oscillator beam that satisfies the coherent component.

[0225] The specific wavelength beam not only enters the fifth lens 4061 but also enters the semiconductor gain chip 4051. After entering the semiconductor gain chip 4051, the specific wavelength beam is reflected by the semiconductor gain chip 4051 and then reaches the silicon photonics chip 4052. This means that the specific wavelength beam reflects back and forth between the silicon photonics chip 4052 and the semiconductor gain chip 4051. The semiconductor gain chip 4051 and the silicon photonics chip 4052 form a resonant cavity, allowing the specific wavelength beam to reflect back and forth between the silicon photonics chip 4052 and the semiconductor gain chip 4051, ensuring stable output of the specific wavelength beam from the semiconductor gain chip. The first lens 4053 couples the specific wavelength beam emitted by the semiconductor gain chip 4051 into the internal fiber adapter.

[0226] Combine Figure 24 、 25 As can be seen from Figures 31 and 31, the optical component 405 also includes an isolator 4054 and a second lens 4055.

[0227] Combine Figure 24 、 26 As can be seen from Figures 31 and 31, the optical component 405 also includes a semiconductor amplifier chip 4056 and a third lens 4057.

[0228] Combine Figure 24 、 27 As can be seen from Figures 31 and 31, the optical component 405 also includes a beam splitter 4058 and a first power monitor 4059.

[0229] Combine Figure 24 、 28 As can be seen from Figures 31 and 31, the optical component 405 also includes a fourth lens 4060.

[0230] Figure 32 FIG. 1 is a structural diagram of a second silicon photonic chip according to some embodiments. Figures 31-32 It can be seen that in some embodiments, the silicon photonic chip 4052 includes an input coupler 40521, a directional coupler 40522, a phase modulator 40523, a first power divider 40524, a second power divider 40525, a first filter 40526, a second filter 40527, a third power monitor 40528, a fourth power monitor 40529, and an output coupler 405210. The input coupler 40521, the directional coupler 40522, the phase modulator 40523, the first power divider 40524, the second power divider 40525, the first filter 40526, the second filter 40527, the third power monitor 40528, the fourth power monitor 40529, and the output coupler 405210 are all formed by the silicon photonic chip using a CMOS process. Specifically,

[0231] The input coupler 40521 and the output coupler 405210 are located on the same side of the silicon photonic chip.

[0232] The input coupler 40521 , the phase modulator 40523 , the first power divider 40524 , the first filter 40526 , the second filter 40527 and the fourth power monitor 40529 have all been introduced and will not be described in detail here.

[0233] The first end of directional coupler 40522 is connected to input coupler 40521 via an optical waveguide. The second end of directional coupler 40522 is connected to phase modulator 40523 via an optical waveguide. The third end of directional coupler 40522 is connected to fourth power monitor 40529 via an optical waveguide. The fourth end of directional coupler 40522 is connected to second power splitter 40525 via an optical waveguide. Directional coupler 40522 splits the input specific wavelength light beam into three light beams. The first light beam is transmitted via the first optical waveguide to input coupler 40521 and then output to the outside of silicon photonic chip 4052 through input coupler 40521. The second light beam is transmitted via the optical waveguide to fourth power monitor 40529, which monitors the optical power of the specific wavelength light beam. The third light beam is transmitted via the optical waveguide to second power splitter 40525 for wavelength locking.

[0234] Second power splitter 40525 is located between directional coupler 40522 and third power monitor 40528, and also between directional coupler 40522 and output coupler 405210, for light splitting. Specifically, a first end of second power splitter 40525 is connected to the fourth end of directional coupler 40522 via an optical waveguide, a second end of second power splitter 40525 is connected to the third power monitor 40528 via an optical waveguide, and a third end of second power splitter 40525 is connected to output coupler 405210 via an optical waveguide. Second power splitter 40525 splits the third light beam split by directional coupler 40522 into two light beams. One light beam is transmitted via an optical waveguide to third power monitor 40528, where it monitors the optical power of the light beam at a specific wavelength. The other light beam is transmitted via an optical waveguide to output coupler 405210.

[0235] The splitting ratio of the second power divider 40525 can be any ratio. When the splitting ratio of the second power divider 40525 changes, the preset value of P1 / P0 also changes. As long as the splitting ratio of the second power divider 40525 changes, the preset value of P1 / P0 can be changed accordingly.

[0236] Third power monitor 40528 is configured to monitor the optical power of a light beam of a specific wavelength in real time. Specifically, third power monitor 40528 is connected to the second end of second power splitter 40525 via an optical waveguide. Third power monitor 40528 monitors the optical power of the light beam split by second power splitter 40525.

[0237] Among them, the power monitor used to monitor the specific wavelength light beam in the silicon photonic chip 4052 is the third power monitor 40528.

[0238] Output coupler 405210, located on one end face of silicon photonics chip 4052, couples a light beam of a specific wavelength into fifth lens 4061. Specifically, output coupler 405210 is connected to second power splitter 40525 via an optical waveguide. Output coupler 405210 couples the other light beam split by second power splitter 40525 into fifth lens 4061.

[0239] In some embodiments, the output coupler 405210 adopts an inclined waveguide design, that is, the waveguide of the output coupler 405210 is set at a certain angle to the end face of the silicon photonic chip 40521, so that the signal light output by the output coupler 405210 is emitted horizontally from the end face of the silicon photonic chip, which is convenient for coupling with the second lens 4055 outside the silicon photonic chip 4052.

[0240] The third power monitor 40528, along with the wavelength calibration component 4062 and the second power monitor 4063 outside the silicon photonics chip 4052, achieves wavelength lock. Specifically, the optical power monitored by the third power monitor 40528 is denoted as P0, and the optical power monitored by the second power monitor 4063 is denoted as P1. The wavelength calibration component 4062 characterizes the wavelength shift direction of the specific wavelength light beam based on the ratio P1 / P0. The wavelength calibration component determines the wavelength shift direction of the specific wavelength light beam based on the ratio P1 / P0 and adjusts the components within the silicon photonics chip 4052 to restore the ratio P1 / P0 to the preset value. When the ratio P1 / P0 returns to the preset value, the selected specific wavelength light beam becomes the preset wavelength light beam.

[0241] like Figure 32 As can be seen, in some embodiments, the second silicon photonic chip further includes multiple absorbers, which are used to absorb the optical power of unwanted light beams to prevent reflection and the generation of stray light. Specifically, the first silicon photonic chip includes a first absorber 405211, a second absorber 405212, a third absorber 405213, and a fourth absorber 405214. The first absorber 405211, the second absorber 405212, the third absorber 405213, and the fourth absorber 405214 have been described above and will not be repeated here.

[0242] Figure 33 FIG. 1 is a structural diagram of a third silicon photonic chip according to some embodiments. Figure 33It can be seen that in some embodiments, the third silicon photonic chip includes an input coupler 40521, a directional coupler 40522, a phase modulator 40523, a first power divider 40524, a second power divider 40525, a first filter 40526, a second filter 40527, a third power monitor 40528, and an output coupler 405210. The input coupler 40521, the directional coupler 40522, the phase modulator 40523, the first power divider 40524, the second power divider 40525, the first filter 40526, the second filter 40527, the third power monitor 40528, and the output coupler 405210 are all formed by the silicon photonic chip using a CMOS process. Specifically,

[0243] The input coupler 40521, the phase modulator 40523, the first power divider 40524, the first filter 40526, the second filter 40527 and the output coupler 405210 have been introduced and will not be repeated here.

[0244] The first end of directional coupler 40522 is connected to input coupler 40521 via an optical waveguide. The second end of directional coupler 40522 is connected to phase modulator 40523 via an optical waveguide. The third end of directional coupler 40522 is connected to second power splitter 40525 via an optical waveguide. Directional coupler 40522 splits an input light beam of a specific wavelength into multiple light beams. The first light beam is transmitted via the first optical waveguide to input coupler 40521, and then output from input coupler 40521 to the outside of silicon photonic chip 4052. The second light beam is transmitted via the optical waveguide to second power splitter 40525 for wavelength locking.

[0245] Second power splitter 40525 is located between directional coupler 40522 and third power monitor 40528, and also between directional coupler 40522 and output coupler 405210, and is used for light splitting. Specifically, a first end of second power splitter 40525 is connected to a third end of directional coupler 40522 via an optical waveguide, a second end of second power splitter 40525 is connected to third power monitor 40528 via an optical waveguide, and a third end of second power splitter 40525 is connected to output coupler 405210 via an optical waveguide. Second power splitter 40525 splits the second light beam split by directional coupler 40522 into two light beams. One light beam is transmitted via an optical waveguide to third power monitor 40528, where it monitors the optical power of the light beam at a specific wavelength. The other light beam is transmitted via an optical waveguide to output coupler 405210.

[0246] A third power monitor 40528 is configured to monitor the optical power of a light beam having a specific wavelength. Specifically, third power monitor 40528 is connected to the second end of second power splitter 40525 via an optical waveguide. Third power monitor 40528 monitors the optical power of the second light beam split by directional coupler 40522, and further monitors the optical power of the first light beam split by directional coupler 40522 and input to semiconductor gain chip 4051.

[0247] Among them, the power monitor used to monitor the specific wavelength light beam in the silicon photonic chip 4052 is the third power monitor 40528.

[0248] Third power monitor 40528 achieves wavelength lock with wavelength calibration component 4062 and second power monitor 4063 outside silicon photonics chip 4052. Specifically, the optical power monitored by third power monitor 40528 is denoted as P0, and the optical power monitored by second power monitor 4063 is denoted as P1. The direction of wavelength change of the specific wavelength light beam is characterized by the ratio P1 / P0. The direction of wavelength shift of the specific wavelength light beam is determined based on the ratio P1 / P0. The components within silicon photonics chip 4052 are adjusted to restore the ratio P1 / P0 to a preset value. When the ratio P1 / P0 returns to the preset value, the selected specific wavelength light beam is the preset wavelength light beam.

[0249] like Figure 33 As can be seen, in some embodiments, the third silicon photonic chip further includes multiple absorbers, which are used to absorb the optical power of useless light beams to prevent reflection and the generation of stray light. Specifically, the third silicon photonic chip includes a first absorber 405211, a second absorber 405212, a third absorber 405213, a fourth absorber 405214, and a fifth absorber 405215.

[0250] The first absorber 405211, the second absorber 405212, the third absorber 405213, the fourth absorber 405214 and the fifth absorber 405215 have been introduced and will not be repeated here.

[0251] The fifth absorber 405215 is connected to the fourth end of the directional coupler 40522 via a fourth straight optical waveguide. The fifth absorber 405215 is configured to absorb the light beam transmitted from the fourth straight optical waveguide. The light beam transmitted from the fourth straight optical waveguide is the third light beam split by the directional coupler 40522.

[0252] In some embodiments, the second and third silicon photonic chips further include a plurality of thermal isolation grooves 405216. The thermal isolation grooves 405216 are formed by etching the surface of the silicon photonic chip 4052. The thermal isolation grooves 405216 are placed between various components within the silicon photonic chip 4052, thereby reducing thermal crosstalk between the various components within the silicon photonic chip 4052 and improving the performance of the silicon photonic chip 4052.

[0253] For the second type of silicon photonic chip, the thermal insulation groove 405216 is placed between the directional coupler 40522 and the phase modulator 40523, between the first power divider 40524 and the first filter 40526, between the first filter 40526 and the second filter 40527, between the second filter 40527 and the third power monitor 40528, between the phase modulator 40523 and the second power divider 40525, and between the directional coupler 40522 and the second power divider 40525.

[0254] Thermal isolation slot 405216 is placed between directional coupler 40522 and phase modulator 40523. This slot reduces thermal crosstalk between directional coupler 40522 and phase modulator 40523. Thermal isolation slot 405216 is placed between first power divider 40524 and first filter 40526. This slot reduces thermal crosstalk between first power divider 40524 and first filter 40526. Thermal isolation slot 405216 is placed between first filter 40526 and second filter 40527. This slot reduces thermal crosstalk between first filter 40526 and second filter 40527. Thermal isolation slot 405216 is placed between second filter 40527 and third power monitor 40528. This slot reduces thermal crosstalk between second filter 40527 and third power monitor 40528. Thermal isolation slot 405216 is placed between phase modulator 40523 and second power divider 40525. This slot reduces thermal crosstalk between phase modulator 40523 and second power divider 40525. Thermal isolation slot 405216 is placed between directional coupler 40522 and second power divider 40525. This slot reduces thermal crosstalk between directional coupler 40522 and second power divider 40525.

[0255] The first, second and third silicon photonic chips are all silicon photonic chips that use CMOS (Complementary Metal Oxide Semiconductor) technology to integrate wavelength-tunable optical components. The first silicon photonic chip also has a wavelength-locked optical component integrated inside. The second and third silicon photonic chips have a power monitor integrated inside them, and the wavelength calibration component and the second power monitor outside the silicon photonic chip form a wavelength-locked optical component.

[0256] In some embodiments, the light source includes a semiconductor gain chip, a silicon photonic chip, a wavelength calibration component, and a second power monitor. The silicon photonic chip is used to receive a light beam of a wavelength range emitted by the semiconductor gain chip, filter a light beam of a specific wavelength from the light beam, and transmit the light beam of the specific wavelength to the semiconductor gain chip and the wavelength calibration component. The semiconductor gain chip and the silicon photonic chip form a resonant cavity, and the light beam of the specific wavelength is reflected back and forth between the semiconductor gain chip and the silicon photonic chip, so that the resonant cavity emits a light beam of the specific wavelength. The second power monitor is used to monitor the optical power of the light beam of the specific wavelength passing through the wavelength calibration component. The silicon photonic chip includes an input coupler, a directional coupler, a wavelength tunable optical component, a second power splitter, a third power monitor, and an output coupler. The directional coupler is respectively connected to the input coupler, the wavelength tunable optical component, and the second power splitter through optical waveguides. The third power monitor and the output coupler are respectively connected to the second power splitter through optical waveguides. The input coupler and the output coupler are located on the same side of the silicon photonic chip. The input coupler, directional coupler, wavelength-tunable optical component, second power splitter, third power monitor, and output coupler are integrated on a silicon photonics chip, saving space and enabling a smaller light source to meet production requirements. The input coupler receives a light beam within a wavelength range emitted by a semiconductor gain chip and transmits a specific wavelength light beam to the semiconductor gain chip. The directional coupler splits the specific wavelength light beam. The wavelength-tunable optical component selects a specific wavelength light beam from the range to achieve wavelength tunability. The second power splitter splits the light beam that passes through it after being split by the directional coupler. The third power monitor monitors the optical power of one of the light beams. The output coupler transmits the other light beam to a wavelength calibration component. The third power monitor, the wavelength calibration component, and the second power monitor form a wavelength-locking optical component. The wavelength-locking optical component detects whether the specific wavelength light beam deviates from the preset wavelength based on the ratio of the optical power measured by the second power monitor to the optical power measured by the third power monitor, thereby achieving wavelength locking. If the specific wavelength light beam deviates from the preset wavelength, the wavelength-tunable optical component is adjusted to maintain the specific wavelength light beam within the preset wavelength. In this application, the input coupler, directional coupler, wavelength-tunable optical component, second power divider, third power monitor and output coupler are integrated on a silicon photonic chip, which saves space and makes the size of the light source smaller to meet production requirements; the wavelength-tunable optical component and the wavelength-locked optical component cooperate to ensure that the specific wavelength light beam output by the light source does not deviate from the preset wavelength light beam.

[0257] Driven by large hyperscale and cloud data center providers, the transmission rate of optical modules is rapidly increasing, such as 200G / 400G high-speed optical modules.

[0258] The optical module provided in the embodiment of the present application is a coherent optical module, and further a silicon photonic coherent optical module; a coherent optical module is an optical module that uses coherent modulation at the transmitting end and uses coherent technology for detection at the receiving end.

[0259] At the transmitting end, in addition to amplitude modulation of light, frequency or phase modulation can also be performed using external modulation, such as QAM. Furthermore, at the transmitting end, external modulation is used to implement high-order modulation using an IQ modulator based on a Mach-Zehnder modulator (MZM), modulating the signal onto an optical carrier, thereby generating light carrying the signal and transmitting it. Specifically, a Mach-Zehnder modulator is internally provided in the silicon photonic chip to achieve power and phase modulation. The Mach-Zehnder modulator modulation adopts the principle of interference of light of the same wavelength. A Mach-Zehnder modulator is provided with two interference arms. A beam of light is input to a single interference arm. A total of two beams of light of the same wavelength need to be provided to a Mach-Zehnder modulator. After modulation by the Mach-Zehnder modulator, the light on the interference arms will merge into one beam of light. A beam of light with a single wavelength can be provided to the silicon photonic chip, and the splitter waveguide inside the silicon photonic chip will split the single wavelength light into two beams of light with the same wavelength, which are respectively input into the two interference arms of the Mach-Zehnder modulator; two beams of light with the same wavelength can also be provided to the silicon photonic chip, and these two beams of light with the same wavelength are directly input into the two interference arms of the Mach-Zehnder modulator respectively; because the Mach-Zehnder modulator will eventually merge the light on each interference arm, under the premise of using a single chip with the same optical power, the solution of providing two beams of light to the silicon photonic chip can provide higher optical power than the solution of providing one beam of light.

[0260] At the receiving end, the local oscillator (LO) light is mixed with the received external optical signal in an optical mixer, generating a difference frequency signal whose frequency, phase, and amplitude follow the same patterns as the external optical signal. The magnitude of the output photocurrent after coherent mixing is proportional to the product of the external optical signal power and the LO light signal power. Because the LO light power is greater than the external optical signal power, the output photocurrent after coherent mixing increases significantly, thereby improving detection sensitivity. Therefore, it can be concluded that in incoherent optical modules, multiple amplifiers are used during transmission to continuously relay and amplify the signal. In coherent optical modules, mixing and amplification of weak incoming signals is performed directly at the receiving end.

[0261] Furthermore, since optical signals will be distorted during transmission in optical fiber links, digital signal processing (DSP) technology is used in the embodiments of the present application to combat and compensate for distortion and reduce the impact of distortion on the system bit error rate. DSP technology can perform various signal compensation processes, such as chromatic dispersion compensation and polarization mode dispersion compensation.

[0262] Figure 34 A related component shown in an embodiment of the present application, Figure 35This is a schematic diagram of a coherent component decomposition shown in an embodiment of the present application, such as Figure 34 and Figure 35 As shown in FIG, a coherent assembly 500 generally includes a cover 501 and a carrier 502. The cover 501 is fastened to the carrier 502 to form a coherent housing with an opening. The outer contour of the housing generally presents a square body.

[0263] A first U-shaped groove 5021 is provided on the side of the carrier plate 502, located at the opening. A mounting groove 5013 is provided on one side of the cover shell 501, and its position corresponds to the position of the first U-shaped groove. The cover shell 501 is provided with a first limiting portion and a second limiting portion for limiting the installation of the carrier plate 502 and the shell. The first limiting portion and the second limiting portion are respectively provided on both sides of the mounting groove. In order to achieve the installation limit of the carrier plate 502 and the cover shell 501, the lower surfaces of the first limiting portion and the second limiting portion are provided lower than the upper surface of the carrier plate 502. During installation, the first limiting portion and the second limiting portion are placed against the side wall of the carrier plate 502 to achieve the limitation in the length direction. The first U-shaped groove 5021 is also called the carrier plate groove.

[0264] The coherent housing has an opening facing the wavelength-tunable optical component. A fiber connector is located at the opening, and a fiber array is located at the connector, including a local oscillator fiber, a receiving fiber, and a transmitting fiber. One end of the fiber connector extends into the opening. One end of the local oscillator fiber is connected to the wavelength-tunable optical component to receive local oscillator light. The receiving fiber is connected to a receiving adapter to receive the external receive signal light sent to the optical module. The transmitting fiber is connected to the transmitting adapter to transmit the modulated transmit signal light.

[0265] The optical fiber fixing member 503 is fixedly connected to the optical fiber connector and the cover shell, and is used to fix the optical fiber connector and the cover shell.

[0266] Figure 36 This is a schematic diagram of a carrier structure used as an example in the present application. As shown in the figure, a coherent optical chip 510 is carried on the carrier 502 for modulation and demodulation of optical signals. An optical port is provided on the side of the coherent optical chip 510, and the end face of the optical port is coupled and connected to the end face of the optical fiber connector. A first electrical chip 520 is provided on the surface of the carrier 502, on the side of the coherent optical chip, and electrically connected to the coherent optical chip. A second electrical chip 530 is provided on the surface of the carrier 502, on the side of the coherent optical chip, and electrically connected to the coherent optical chip. A third electrical chip 540 is provided on the surface of the carrier 502, on the side of the coherent optical chip, and electrically connected to the coherent optical chip.

[0267] In this example, the first electrical chip 520 is a coherent transmit driver chip, located opposite the optical port of the coherent optical chip, and is used to drive the coherent modulator in the coherent optical chip. The second electrical chip 530 and the third electrical chip 540 are receive amplifier chips, located adjacent to the coherent transmit driver chip and close to the coherent optical chip, and are used to amplify received electrical signals.

[0268] Carrier board 502 also carries multiple power supply circuits for the coherent optical chip's internal balanced receiver, power monitor, and transmit optical attenuator. The specific configuration of these components is determined by the coherent optical chip's functional pin configuration. Carrier board 502 is a high-speed carrier board, electrically connected to the circuit board via conductive areas on its sides or bottom surface.

[0269] Because the optoelectronic chips on the surface of carrier board 502 are relatively tall and heavy, and their distribution is relatively concentrated, the center of gravity of carrier board 502 is not near its geometric center of gravity, but rather close to the coherent optical chips. To increase the structural stability of coherent assembly 500 and ensure that its geometric center and center of gravity coincide as closely as possible, the center of gravity of cover 501 is positioned symmetrically with the center of gravity of carrier board 502.

[0270] Figure 37 A schematic diagram of the structure of a cover shell for this application example Figure 1 , Figure 38 A schematic diagram of the structure of a cover shell for this application example Figure 2 . Figure 37 and Figure 38 The following are schematic diagrams of the structure of the cover 501 at different angles. The cover 501 is a rectangular structure. A mounting groove 5013 is provided on one side of the cover 501, and its position corresponds to the position of the first U-shaped groove. The cover 501 is provided with a first limiting portion 5011 and a second limiting portion 5012 for limiting the installation of the carrier 502 and the housing. The first limiting portion 5011 and the second limiting portion 5012 are respectively provided on either side of the mounting groove 5013. To achieve the installation and limiting of the carrier 502 and the cover 501, the lower surfaces of the first limiting portion 5011 and the second limiting portion 5012 are provided lower than the upper surface of the carrier 502. During installation, the first limiting portion 5011 and the second limiting portion 5012 are placed against the side wall of the carrier 502 to achieve lengthwise limiting. The cover shell 501 is provided with a related mounting protrusion protruding from the upper surface of the cover shell 501 and arranged along the shape of the mounting groove, and is used for connection and limiting between the cover shell 501 and the extension portion.

[0271] To ensure a smooth surface for the coherent assembly 500 and facilitate its installation within the optical module, a carrier plate 50111 is provided around the mounting groove. Its upper surface is connected to the lower surface of the extension, limiting the vertical position of the optical fiber fixture on the cover 501. In this example, the upper surface of the extension is flush with the upper surface of the coherent mounting protrusion 5016.

[0272] The side walls of the coherent mounting protrusion are in abutment connection with the side walls of the extension portion, thereby limiting the extension portion in the horizontal direction and further achieving coupling limitation between the optical fiber array and the coherent optical chip.

[0273] In order to facilitate the limiting of the extended part of the optical fiber fixing part and the coherent mounting protrusion, the supporting plate 50111 is provided with an installation limiting part, including: a first installation limiting part 5014 and a second installation limiting part 5015. The first installation limiting part 5014 and the second installation limiting part 5015 are provided to protrude from the upper surface of the supporting plate. For the integrity of the surface of the coherent component, the upper surfaces of the first installation limiting part 5014 and the second installation limiting part 5015 are flush with the upper surface of the coherent mounting protrusion 5016.

[0274] In the example of the present application, the first installation stop portion 5014 and the second installation stop portion 5015 can be symmetrically arranged or asymmetrically arranged. For ease of installation and use, the first installation stop portion 5014 and the second installation stop portion 5015 are symmetrically arranged. The first installation stop portion 5014 and the second installation stop portion 5015 can be arranged in a semicircular shape, or in a triangular shape or other geometric shape.

[0275] The lower surface of the cover 501 is provided with support arms, which are located around the lower surface of the cover 501 and are used to connect with the carrier board.

[0276] The lower surface of the cover 501 is provided with cover protrusions of varying heights to accommodate the structure of the optoelectronic devices on the carrier 502. The cover 501 is provided with a connecting portion that connects to the upper surface of the carrier 502 and protrudes from the lower surface of the cover 501. The lower surface of the cover 501 is provided with a first raised platform 5018 and a second raised platform 5017 of varying heights. The first raised platform 5018 protrudes from the lower surface of the cover 501, corresponding to the positions of the first, second, and third electronic chips. The lower surface of the first raised platform 5018 is higher than the lower surface of the second raised platform, and the lower surface of the second raised platform 5017 is higher than the connecting portion. The first raised platform 5018 includes a first sub-platform 50181 and a second sub-platform 50182. The first sub-platform 50181 is disposed above the first electronic chip 520, and its projection on the carrier 502 covers the first electronic chip 520. The second sub-platform 50182 is disposed above the second electronic chip 530 and the third electronic chip 540, and its projection on the carrier 502 covers the second electronic chip 530 and the third electronic chip 540. The bottom surface of the cover 501 covers the coherent optical chip.

[0277] The second raised platform 5017 covers the other electrical components on the carrier 502. It is located at the edge of the first raised platform 5018, between the first raised platform 5018 and the connector. The second raised platform 5017 also has a raised connector 5019 located at the corner farthest from the coherent optical chip. This connector is connected to the carrier 502 via conductive silver adhesive, allowing heat from the carrier 502 to be dissipated through the raised connector and the cover 501.

[0278] In this example, the first raised platform 5018 and the second raised platform 5017 are positioned diagonally opposite the coherent optical chip. Because the thickness of the first raised platform 5018 and the second raised platform 5017 is greater than the thickness of the bottom surface of the cover 501, the center of gravity of the cover 501 is located near the second raised platform 5017. When the cover 501 and the carrier 502 are assembled, the center of gravity of the coherent component 500 is positioned as close to the geometric center as possible, ensuring the stability of the coherent component 500.

[0279] Figure 39 This is a schematic diagram of the connection between the optical fiber connector and the coherent component of the example of this application, as shown in Figure 39 As shown in FIG, the coherent connection plate 550 is connected between the coherent optical chip 510 and the optical fiber connector 504 to fix the coherent optical chip and the optical fiber connector. The optical fiber adapter is connected to the optical fiber inside the optical fiber connector.

[0280] To prevent light in the optical fiber connector from being reflected at the connection between the end face of the optical fiber connector and the end face of the coherent optical chip, thereby affecting the optical power, the central axis of the optical fiber array and the central axis of the optical port of the coherent optical chip are at an angle of 6° to 8° to reduce light reflection at the connection between the end face of the optical fiber connector and the end face of the coherent optical chip.

[0281] In this example, the optical fiber connector 504 is a rectangular parallelepiped, with a coherent connection plate 550 positioned above it, spanning the coherent optical chip and the optical fiber connector. A colloid is applied to the lower surface of the coherent connection plate 550 to securely connect the coherent connection plate 550 to the optical fiber connector and to the coherent optical chip.

[0282] In order to reduce the pulling of the optical fiber by external forces during transportation or use, which leads to the deterioration of the coupling accuracy between the optical fiber connector and the coherent optical chip, a pigtail sleeve 5041 is also provided in the present application, which is sleeved on the outside of the optical fiber array. The optical fiber fixing part is provided on the outside of the optical fiber connector and is fixedly connected to the pigtail sleeve. The upper surface of the pigtail sleeve 5041 is provided with a double-sided adhesive material or glue material, which is connected to the optical fiber fixing part. In the example of the present application, the pigtail sleeve is a square tube body with a through hole, the optical fiber array passes through one end of the square tube body, the optical fiber connector is against the end of the square tube body, and the optical fiber array and the pigtail sleeve are filled with colloid for connection.

[0283] Figure 40 This is a schematic diagram of the structure of an optical fiber fixing member used in this application example. Figure 1 . Figure 41 Schematic diagram of the structure of the optical fiber fixing part Figure 2 .like Figure 39 and Figure 40 The optical fiber fixture is shown from different angles. It has a uniform thickness and is die-cast from a single sheet of material. It includes a fixed base plate 5031 and first and second optical fiber side plates 5032 and 5033 disposed on either side of the fixed base plate. The fixed base plate 5031 includes a first fixed base plate 50311 and a second fixed base plate 50312 of varying heights, with the upper surface of the second fixed base plate 50312 positioned higher than the upper surface of the first fixed base plate. A pigtail sleeve 5041 is positioned within the space enclosed by the first fixed base plate, the first optical fiber side plate, and the second optical fiber side plate. A coherent connection plate 550 is positioned above the upper surface of the coherent optical chip and the optical fiber connector, with the upper surface of the coherent connection plate 550 being higher than the upper surface of the optical fiber connector. The upper surface of the coherent connection plate 550 is connected to the second fixed base plate 50312. The different heights of the first and second fixed base plates 50312 are used to accommodate the height of the coherent connection plate 550.

[0284] The upper surface of the pigtail sleeve is connected to the lower surface of the first fixed bottom plate, and the side surface thereof is connected to the first optical fiber side plate and the second optical fiber side plate.

[0285] An extension portion 50313 is provided on one side of the second fixed base plate 50312, its width being greater than that of the fixed base plate. A first extension stopper groove 503131 and a second extension stopper groove 503132 are provided on the side of the extension portion 50313, which align with corresponding structures on the upper surface of the cover 501 to facilitate the connection and fixation between the optical fiber fixture and the cover 501. To facilitate the connection and fixation between the optical fiber fixture and the cover 501, the side of the extension portion 50313 is also provided with multiple glue dispensing grooves 5034. After the extension portion 50313 and the cover 501 are aligned, liquid glue is dispensed into the glue dispensing grooves to secure the extension portion 50313 to the cover 501.

[0286] In the example of the present application, the glue dispensing groove has the same shape as the first extension limiting groove and the second extension limiting groove.

[0287] The first extension limiting groove 503131 is matched and connected with the first installation limiting portion 5014 , and the second extension limiting groove 503132 is matched and connected with the second installation limiting portion 5015 .

[0288] During the installation process of the present application example, the coherent optical chip is first installed and connected to the carrier board 502, the pigtail sleeve 5041 is connected to the optical fiber array, and the optical port of the coherent optical chip protrudes from the first U-shaped groove of the carrier board 502. Then, the coherent connection plate 550 is connected across the top of the optical fiber connector and the coherent optical chip to achieve the coupling connection between the optical fiber connector and the coherent optical chip. The cover 501 is then connected to the edge of the carrier board 502. During the installation process, the first and second limiting portions abut the sides of the carrier board 502, the connection portion of the cover 501 is connected to the carrier board 502, and the raised connection portion is connected to the edge of the carrier board 502. The first fixing base plate of the optical fiber fixing member is connected to the pigtail sleeve 5041, the second fixing base plate 50312 is connected to the coherent connection plate 550, and the extension portion 50313 is connected to the carrier board 502 on the upper surface of the cover 501. Through the above connection, the optical fiber connector is fixedly connected to the optical fiber fixing part through the pigtail sleeve 5041 and the coherent connection plate 550. When the optical fiber is subjected to external force, the force is dispersed and transferred through the connection, thereby reducing the force on the optical fiber connector, improving the connection stability between the optical fiber connector and the coherent optical chip, and avoiding the optical coupling accuracy.

[0289] In the example of this application, the optical fiber array and the coherent optical chip are connected by a glass bridge and connected with soft glue, which has strong maintainability and is conducive to production and manufacturing. The upper shell is divided into two parts: the optical fiber fixing part is die-cast, and the cover shell 501 is made of sheet metal. The overall thickness of the product is only 2.42mm, which meets the packaging requirements of the SFP-DD optical module. A pigtail sleeve 5041 is designed on the outside of the optical fiber array. When in use, it is fixed to the optical fiber fixing part with glue, and the optical fiber fixing part is then fixed to the cover shell 501 with glue to protect the optical end face of the optical fiber array and the coherent optical chip from external force. Multiple grooves are designed on both sides of the bonding part of the metal cover shell 501 and the optical fiber fixing part for glue fixation to improve the stability of the connection.

[0290] In order to improve the efficiency of optical communication, in the coherent component 500 of the example of this application, the coherent modulator is a dual-polarization coherent modulator, the emitted signal light is a coupled light beam of signal light with different polarization directions, and the received signal light contains two groups of signal light with different polarization directions, realizing single-channel multi-signal transmission.

[0291] Figure 42 This is a schematic diagram of the structure of a coherent optical chip exemplified in the present application. As shown in the figure, the layout scheme of a high-speed coherent optical chip proposed in the present application adopts silicon photonic integration technology and integrates dual-polarization coherent transmission and reception functions in a single chip. The fiber coupling port includes three fiber coupling ports, namely, a receiving fiber coupling port 5111, a local oscillator fiber coupling port 5112, and a transmitting fiber coupling port 5113 from top to bottom. The local oscillator fiber coupling port 5112 is connected to an external local oscillator light source via a polarization-maintaining fiber. After the light from the external local oscillator light source enters the chip, it is split into two beams. One beam, as the transmitting light, enters the dual-polarization coherent modulator. After being loaded with an electro-optical signal and polarized by a polarization rotation combiner 5141, it is output from the transmitting fiber coupling port 5113. The other beam, as the local oscillator light, is split again and enters the first polarization-balanced detector and the second polarization-balanced detector respectively. It is optically mixed with the light processed by the polarization rotation beam splitter entering from the receiving fiber coupling port 5111, thereby realizing signal demodulation processing.

[0292] To facilitate active coupling between the fiber coupling port and the fiber array, a transmit coupling power monitor and a receive coupling power monitor are integrated behind the polarization rotation combiner 5141 and the polarization rotation beam splitter, respectively, for active coupling of the fiber array. At the receiving end, a small portion of each of the two beams after passing through the polarization rotation beam splitter enters the same receive coupling power monitor for real-time active coupling monitoring. At the transmitting end, a small portion of each of the two beams after passing through the polarization rotation beam splitter enters the same transmit coupling power monitor for real-time active coupling monitoring. Furthermore, to reduce the impact of different polarization states on the coupling power monitor and improve the accuracy of active coupling monitoring, a polarization beam splitter can be integrated before the coupling power monitor to improve the polarization purity of the monitored light, thereby enhancing the accuracy of active coupling monitoring.

[0293] The optical port of the coherent optical chip is equipped with a fiber coupling port, which is coupled to the optical fiber connector. The fiber coupling ports include a receiving fiber coupling port 5111, a local oscillator fiber coupling port 5112, and a transmitting fiber coupling port 5113. A polarization-balanced receiver, connected to the receiving fiber coupling port 5111 and the local oscillator fiber coupling port 5112, is used to convert the received signal light into a received electrical signal. A dual-polarization coherent modulator, connected to the transmitting fiber coupling port 511 and the local oscillator fiber coupling port 5112, is used to convert the transmit electrical signal emitted by the DSP chip into an optical signal and load it into the local oscillator light to form the transmit signal light.

[0294] The receiving fiber coupling port 5111 is connected to the receiving fiber adapter and is used to receive signal light from the other end. For convenience, this is referred to as received signal light, which is a coupled beam of first and second received signal lights having different polarization directions. The polarization rotation beam splitter 5121 is connected to the fiber coupling port via an optical waveguide and is used to split the received signal light into a first and second received signal lights based on their polarization directions. The local oscillator fiber coupling port 5112 receives local oscillator light emitted by the wavelength-tunable optical component and splits the local oscillator light into a first sub-local oscillator light and a second sub-local oscillator light via an optical waveguide. The first sub-local oscillator light is further divided into a first received local oscillator light and a second received local oscillator light.

[0295] The first received local oscillator light and the first received signal light are coupled into the first polarization balanced receiver 5123. The first polarization balanced receiver 5123 converts the first received signal light into a first received electrical signal by mixing and balanced detection of the first received local oscillator light and the first received signal light. After amplification by the first receiving amplifier chip, the first received electrical signal enters the DSP chip and is converted into a first received digital signal.

[0296] The second received local oscillator light and the second received signal light are coupled into the second polarization balanced receiver 5124. The second polarization balanced receiver 5124 converts the second received signal light into a second received electrical signal by mixing and balanced detection of the second received local oscillator light and the second received signal light. After amplification by the second receiving amplifier chip, the second received electrical signal enters the DSP chip and is converted into a second received digital signal.

[0297] To facilitate monitoring of the coupling accuracy between the receiving optical fiber and the receiving optical fiber coupling port 5111, during coupling installation, test light, including first, second, and third test lights, is connected to the outside of the optical fiber coupling port. During this process, the test light all enters the coherent optical chip from outside the coherent optical chip. The coherent optical chip is also provided with a receiving coupling power monitor 5122, which receives portions of light from the two outgoing optical paths of the polarization rotating beam splitter 5121 to monitor the coupling power. The MCU is electrically connected to the receiving coupling power monitor 5122, receives the electrical signal from the receiving coupling power monitor 5122, calculates the optical power at the optical fiber coupling port based on the electrical signal from the receiving coupling power monitor 5122, and adjusts the coupling accuracy between the receiving optical fiber coupler and the receiving optical fiber based on the comparison of the optical power at the optical fiber coupling port with the optical power of the first test light. Specifically, a first test light power threshold range is set within the MCU. If the optical power at the optical fiber coupling port is not within the first test light power threshold range, the coupling accuracy between the receiving optical fiber and the receiving optical fiber coupling port 5111 needs to be adjusted.

[0298] To simplify the waveguide path within the coherent optical chip, the local oscillator fiber coupling port 5112 is disposed between the receiving fiber coupling port 5111 and the transmitting fiber coupling port 511 .

[0299] In this application, the node positions shown in the figure are used to split some light. For example, at node 5125, the optical waveguide between node 5125 and the first light output port of the polarization-rotating beam splitter 5121 is called the first waveguide, the optical waveguide between the receive-coupled power monitor 5122 and node 5125 is called the second waveguide, and the optical waveguide between the first polarization-balanced receiver 5123 and node 5125 is called the third waveguide. To split the light from the first light output port of the polarization-rotating beam splitter 5121, a directional coupler is provided at the node, and the receive-coupled power monitor 5122 is provided between node 5125 and the first polarization-balanced receiver 5123. Similarly, the receive-coupled power monitor 5122 is provided between node 5126 and the second polarization-balanced receiver 5124.

[0300] The dual-polarization coherent modulator 516 is connected to the transmitting fiber coupling port 511 and the local oscillator fiber coupling port 5112 through an optical waveguide, and is used to convert the transmitting electrical signal emitted by the DSP chip into an optical signal and load it into the local oscillator light to form a transmitting signal light.

[0301] In order to facilitate active coupling between the fiber coupling port and the fiber array, a transmission coupling power monitor is provided between the two input ends of the polarization rotation combiner 5141 .

[0302] To facilitate monitoring of the coupling accuracy between the transmitting optical fiber and the transmitting optical fiber coupling port 511, during coupling installation, test light, including a first test light, a second test light, and a third test light, is connected to the outside of the optical fiber coupling port. During this process, the test light all enters the coherent optical chip from outside the coherent optical chip, with the first test light entering from the receiving optical fiber coupling port 5111, the second test light entering from the local oscillator optical fiber coupling port 5112, and the third test light connected from the transmitting optical fiber coupling port 511. The coherent optical chip is also provided with a transmitting coupling power monitor 5143, which transmits part of the light from the two input ends of the polarization rotation combiner 5141 to monitor the coupling power. The MCU is electrically connected to the transmitting coupling power monitor 5143, receives the electrical signal from the transmitting coupling power monitor 5143, calculates the optical power of the transmitting optical fiber coupling port 511 based on the electrical signal from the transmitting coupling power monitor 5143, and adjusts the coupling accuracy between the transmitting optical fiber receiving coupler and the transmitting optical fiber based on the comparison of the optical power of the optical fiber coupling port with the optical power of the third test light. Specifically, a second test optical power threshold interval is set in the MCU. If the optical power of the transmitting fiber coupling port 511 is not within the second test optical power threshold interval, the coupling accuracy between the transmitting fiber and the transmitting fiber coupling port 511 needs to be adjusted.

[0303] Figure 43 This is a schematic diagram of the structure of a coherent optical chip used in this application example. Figure 2 To reduce the impact of different polarization states on the coupled power monitor and improve the accuracy of active coupled monitoring, a first polarization beam splitter 5128 is provided between the receive coupled power monitor 5122 and the first light output port of the polarization rotation beam splitter 5121 to prevent light that does not belong to the first polarization state from entering the receive coupled power monitor 5122. Similarly, a second polarization beam splitter 5127 is provided between the receive coupled power monitor 5122 and the second light output port of the polarization rotation beam splitter 5121 to prevent light that does not belong to the second polarization state from entering the receive coupled power monitor 5122.

[0304] To facilitate monitoring of the coupling accuracy between the receiving fiber and the receiving fiber coupling port 5111, during coupling installation, test light, including first, second, and third test lights, is connected to the outside of the fiber coupling port. During this process, the test light all enters the coherent optical chip from outside the coherent optical chip. The first test light enters the coherent optical chip through the receiving fiber coupling port 5111 and receives portions of light from the two right-side outgoing optical paths of the polarization rotation beam splitter 5121, generating first and second sub-test lights with different polarization directions. For example, the first sub-test light is X-polarized light, and the second sub-test light is Y-polarized light. The receiving polarization rotation beam splitter 5121 transmits the X-polarized light through the first path (above), whereupon part of the X-polarized light enters the first polarization-balanced detector and part enters the first polarization beam splitter 5128. The first polarization beam splitter 5128 allows the X-polarized light in the light beam transmitted to the first polarization beam splitter 5128 to pass through, while filtering out light in other directions. The receiving polarization rotation beam splitter 5121 transmits the Y-polarized light through the second path (below), partially entering the second polarization balance detector and partially entering the second polarization beam splitter. The second polarization beam splitter allows the Y-polarized light in the light beam transmitted to the second polarization beam splitter to pass through, while filtering out light in other directions. The receiving coupling power monitor 5122 monitors the coupling power. The MCU is electrically connected to the receiving coupling power monitor 5122 and receives the electrical signal from the receiving coupling power monitor 5122. The optical power of the fiber coupling port is calculated based on the electrical signal from the receiving coupling power monitor 5122. The optical power of the fiber coupling port is compared with the optical power of the first test light to adjust the coupling accuracy between the receiving fiber coupler and the receiving fiber. Specifically, a first test light power threshold range is set in the MCU. If the optical power of the fiber coupling port is not within the first test light power threshold range, the coupling accuracy between the receiving fiber and the receiving fiber coupling port 5111 needs to be adjusted.

[0305] Similarly, to reduce the impact of different polarization states on the coupling power monitor and improve the accuracy of active coupling monitoring, a first transmit polarization beam splitter 5161 is provided between the transmit coupling power monitor 5143 and the first input end of the polarization rotation beam combiner 5141 to prevent light that does not belong to the first polarization state from entering the receive coupling power monitor 5122. A second receive polarization beam splitter 5162 is provided between the transmit coupling power monitor 5143 and the second input end of the polarization rotation beam combiner 5141 to prevent light that does not belong to the second polarization state from entering the receive coupling power monitor 5122.

[0306] Continue to combine Figure 42 、 Figure 43As shown, in this example, during operation, the local oscillator fiber coupling port 5112 receives the local oscillator light emitted by the wavelength-tunable optical component and splits the local oscillator light into a first sub-local oscillator light and a second sub-local oscillator light via an optical waveguide. The first sub-local oscillator light is further split into a first received local oscillator light and a second received local oscillator light. The second received local oscillator light is further split into a first transmitted light and a second transmitted light, which respectively enter the two input ports of the dual-polarization coherent modulator 516.

[0307] For example, the dual-polarization coherent modulator 516 has a first optical input port for receiving a first transmitted light and a second optical input port for receiving a second transmitted light. The dual-polarization coherent modulator 516 modulates the first transmitted light and the second transmitted light, respectively, and outputs a first transmitted signal light and a second transmitted signal light. The polarization rotation combiner 5141 is connected to the first and second output ports of the dual-polarization coherent modulator 516, rotates the first and second transmitted signal lights into beams with mutually perpendicular polarization directions, and couples the combined beams to output the transmitted signal light.

[0308] The first and second emission lights have the same polarization direction, but different amplitudes and phases to carry different signals. The polarization rotation combiner 5141 deflects one of the first or second emission lights, forming an angle of approximately 90° with the other light beam, and then combines them into a single emission signal light beam. The polarization rotation combiner 5141 includes a first input end, a second input end, and an output end, wherein the first input end is connected to the first output end of the dual-polarization coherent modulator 516, the second input end is connected to the second output end of the dual-polarization coherent modulator 516, and the output end is connected to the emission fiber coupling port 511, and the emission signal light enters the emission fiber through the emission fiber coupling port 511.

[0309] The coherent optical chip also includes a first transmit optical attenuator 5144, located between the polarization rotation beam combiner 5141 and the first polarization coherent modulator 5142, to control the attenuation of the first transmit signal light. To control the first transmit optical attenuator 5144, a first optical attenuator power monitor 5145 is provided at the second output of the first transmit optical attenuator 5144. The first output of the first transmit optical attenuator 5144 is connected to the first input of the transmit polarization rotation beam combiner 5141. The MCU is electrically connected to the first optical attenuator power monitor 5145 and controls the output voltage of the first transmit optical attenuator 5144 based on data collected by the first optical attenuator power monitor 5145.

[0310] To more accurately monitor the transmitted optical power, a first transmit power monitor 5147 is provided between the second output port of the first transmit optical attenuator 5144 and the polarization rotation combiner 5141 to monitor the optical power of the attenuated first transmit signal light. An MCU is electrically connected to the first transmit power monitor 5147, allowing a host computer to read the optical power of the first transmit signal light stored in the MCU.

[0311] Similarly, the coherent optical chip also includes a second transmit optical attenuator 5154, located between the polarization rotation beam combiner 5141 and the second polarization coherent modulator 5152, to control the attenuation of the second transmit signal light. To control the second transmit optical attenuator 5154, a second optical attenuator power monitor 5155 is provided at the second output end of the second transmit optical attenuator 5154. The first output end of the second transmit optical attenuator 5154 is connected to the second input end of the transmit polarization rotation beam combiner 5141. The MCU is electrically connected to the second optical attenuator power monitor 5155 and controls the output voltage of the second transmit optical attenuator 5154 based on the data collected by the second optical attenuator power monitor 5155.

[0312] To more accurately monitor the transmitted optical power, a second transmit power monitor 5157 is provided between the second transmit optical attenuator 5154 and the polarization rotation combiner 5141 to monitor the optical power of the attenuated second transmit signal light. The MCU is electrically connected to the second transmit power monitor, allowing the host computer to read the optical power of the second transmit signal light stored in the MCU.

[0313] A first modulator power monitor 5146 is provided between the first transmit optical attenuator 5144 and the first polarization coherent modulator 5142 to monitor the phase of the first transmit optical signal. The first modulator power monitor 5146 is connected to the MCU. The MCU receives monitoring data from the first modulator power monitor 5146 and performs phase modulation on the first transmit optical signal.

[0314] Figure 44 This is a coherent optical chip surface bumping layout proposed in the example of this application, such as Figure 44 As shown, the dual-polarization coherent modulator conductive area 5171 and the fiber coupling port conductive area 5172 are respectively distributed on the upper and lower sides of the coherent optical chip surface, the first polarization balanced receiver conductive area 5173 and the second polarization balanced receiver conductive area 5174 are distributed on the left side of the coherent optical chip, and other DC signal implants are distributed around the coherent optical chip to facilitate signal interconnection with external electronic chips. The middle part of the coherent optical chip is evenly filled with implants to improve the reliability and stability of the 2.5D flip-chip package. These implants have no actual function and can be grounded or disconnected.

[0315] To facilitate the coupling and packaging of the fiber array and fiber coupling port, the spacing between the implant balls surrounding the fiber coupling port and the fiber coupling port must be greater than 0.5mm. The fiber coupling port contains five coupling ports: the receive coupling port, the local oscillator coupling port, and the transmit coupling port, from left to right. The two ports on the right are loopback test ports for coupling testing. To improve coupling efficiency and reworkability with the FA, the fiber coupler utilizes silicon nitride material and a direct scribe-and-dissect method to ensure the perpendicularity of the fiber coupling port end face.

[0316] In some examples of this application, such as Figure 45 and Figure 46 As shown, the first local oscillator optical splitter 5131 has its input end connected to the local oscillator fiber coupling port, its first output end connected to the first polarization coherent modulator 5412, and its second output end connected to the input end of the second local oscillator optical splitter 5132; the first output end of the second local oscillator optical splitter 5132 is connected to the second polarization coherent modulator 5152, and its second output end is connected to the input end of the third local oscillator optical splitter 5133; the first output end of the third local oscillator optical splitter 5133 is connected to the first polarization balanced receiver, and the second output end is connected to the second polarization balanced receiver. Alternatively, the first local oscillator optical splitter has its input end connected to the local oscillator fiber coupling port, its first output end connected to the input end of the second local oscillator optical splitter, and its second output end connected to the input end of the third local oscillator optical splitter; the first output end of the third local oscillator optical splitter is connected to the first polarization coherent modulator, and its second output end is connected to the first polarization coherent modulator; the first output end of the second local oscillator optical splitter is connected to the first polarization balanced receiver, and the second output end is connected to the second polarization balanced receiver.

[0317] In the above coherent optical chip, in order to increase the effective emission light power and ensure that the optical power of the emission light output by the two polarization coherent modulators in different directions is basically consistent, in this application, a power splitter is used at the first local oscillator splitter 5131, the second local oscillator splitter 5132 and the third local oscillator splitter 51333 to divide the light into two equal beams. Figure 44 As shown in . After light from an external local oscillator light source enters the chip, it is split into two beams with optical powers of 50% and 50%, respectively, at the first local oscillator beam splitter 5131. One of the beams, serving as the transmitted light, is equally split into two beams at the fourth local oscillator beam splitter 5134. These beams enter the first polarization coherent modulator and the second polarization coherent modulator, respectively. After being loaded with an electro-optical signal and polarized by the polarization rotation beam combiner 5141, they are output from the transmitting fiber coupling port 5113. The other beam, serving as the local oscillator light, is again split by the third local oscillator beam splitter 5133 and enters the first polarization-balanced detector 5123 and the second polarization-balanced detector 5124, respectively. There, they undergo optical mixing with the light processed by the polarization rotation beam splitter 5121 and entering from the receiving fiber coupling port 5111.

[0318] At the first local oscillator splitter 5131, the light is divided into two beams with optical powers of 50% and 50% respectively. One beam is used as the transmitted light and is equally divided into two beams at the fourth local oscillator splitter 5134, which enter the first polarization coherent modulator 5142 and the second polarization coherent modulator 5152 respectively. Therefore, the optical powers of the light entering the first polarization coherent modulator and the second polarization coherent modulator are the same.

[0319] To avoid a significant difference in optical power output between the first and second polarization coherent modulators due to different optical losses during the modulation process by different coherent modulators, a first transmit optical attenuator 5144 is provided between the polarization rotation combiner 5141 and the first polarization coherent modulator 5142 to control the attenuation of the first transmit signal light. To control the first transmit optical attenuator 5144, a first optical attenuator power monitor 5145 is provided at the second output end of the first transmit optical attenuator 5144. The first output end of the first transmit optical attenuator 5144 is connected to the first input end of the transmit polarization rotation combiner 5141. The MCU is electrically connected to the first optical attenuator power monitor 5145 and controls the output voltage of the first transmit optical attenuator 5144 based on data collected by the first optical attenuator power monitor 5145.

[0320] A first transmit power monitor 5147 is provided between the second output port of the first transmit optical attenuator 5144 and the polarization rotation combiner 5141 to monitor the optical power of the attenuated first transmit signal light. An MCU is electrically connected to the first transmit power monitor 5147, allowing a host computer to read the optical power of the first transmit signal light stored in the MCU.

[0321] The coherent optical chip also includes a second transmit optical attenuator 5154, located between the polarization rotation combiner 5141 and the second polarization coherent modulator 5152, to control the attenuation of the second transmit signal light. To control the second transmit optical attenuator 5154, a second optical attenuator power monitor 5155 is provided at the second output of the second transmit optical attenuator 5154. The first output of the second transmit optical attenuator 5154 is connected to the second input of the transmit polarization rotation combiner 5141. The MCU is electrically connected to the second optical attenuator power monitor 5155 and uses the data collected by the second optical attenuator power monitor 5155 to control the output voltage of the second transmit optical attenuator 5154.

[0322] A second transmit power monitor 5157 is provided between the second transmit optical attenuator 5154 and the polarization rotation combiner 5141 to monitor the optical power of the attenuated second transmit signal light. An MCU is electrically connected to the second transmit power monitor, allowing the host computer to read the optical power of the second transmit signal light stored in the MCU.

[0323] In this application, in order to increase the effective transmitted light power, the difference in the optical power of the transmitted light output by two polarization coherent modulators in different directions should not be greater than 15%, that is, the difference between the first polarization coherent modulator and the second polarization coherent modulator should not be greater than 15% of the ratio of the difference between the first polarization coherent modulator and the second polarization coherent modulator.

[0324] The MCU can control the attenuation value of the first optical attenuator or the second optical attenuator by monitoring the optical power of the first transmitted signal light and the optical power of the second transmitted signal light, so that the difference ratio between the first polarization coherent modulator and the second polarization coherent modulator is within a preset difference ratio range.

[0325] The present application also provides another embodiment in which the first local oscillator beam splitter 5131 and the fourth local oscillator beam splitter 5134 are adjustable beam splitters. The transmitted optical power can be controlled by controlling the splitting ratio at the output ends of the first and third local oscillator beam splitters. To increase the effective transmitted optical power and ensure that the optical power of the transmitted light output by the two polarization coherent modulators in different directions remains substantially consistent, the difference between the output optical power of the first polarization coherent modulator and the output optical power of the second polarization coherent modulator is controlled to be no greater than 15%.

[0326] In the above coherent optical chip, the insertion loss of the fiber coupling port and the polarization rotation combiner 5141 for light of different polarization states will be different. In particular, the optical insertion loss of the fiber coupling port will also be affected by the chip processing technology. In practical applications, it is required that the optical power of the two different polarizations emitted from the transmitting end is balanced. Therefore, the present application provides another schematic diagram of the coherent optical chip structure, in which an adjustable optical attenuator integrated on the coherent optical chip is used to attenuate the optical power of the higher-power polarization state, thereby reducing the effective optical transmission power and affecting the chip yield. Figure 47 A schematic diagram of the coherent optical chip structure provided in this application Figure 5 ,like Figure 47 As shown in , the fiber coupler includes three fiber coupling ports, namely, from top to bottom, a receiving fiber coupling port 5111, a local oscillator fiber coupling port 5112, and a transmitting fiber coupling port 511. The local oscillator fiber coupling port 5112 is connected to an external local oscillator light source via a polarization-maintaining fiber. The first local oscillator splitter 5131 is an unbalanced splitter, the input end of which is connected to the local oscillator fiber coupling port 5112, the first output end of which is connected to the first polarization-coherent modulator, and the second output end of which is connected to the input end of the second local oscillator splitter. The first output end of the second local oscillator splitter 5132 is connected to the second polarization-coherent modulator, and the second output end is connected to the input end of the third local oscillator splitter. The first output end of the third local oscillator splitter 5133 is connected to the first polarization-balanced receiver 5123, and the second output end is connected to the second polarization-balanced receiver 5124.

[0327] After light from the external local oscillator light source enters the coherent optical chip, it is split into two beams by an unbalanced optical splitter. One beam, as the transmitted light, enters the first polarization coherent modulator 5142. After being loaded with an electro-optical signal and polarized by the polarization rotation beam combiner 5141, it is output from the transmitting fiber coupling port 5113. The other beam, as the local oscillator light, is again split into two beams by the second local oscillator optical splitter 5132. One beam, as the transmitted light, enters the second polarization coherent modulator 5152. After being loaded with an electro-optical signal and polarized by the polarization rotation beam combiner 5141, it is output from the transmitting fiber coupling port 511 and the transmitting fiber coupling port 5113. The other output port of the second local oscillator optical splitter 5132 is connected to the input port of the third local oscillator optical splitter 5133. The two beams are split into two beams by the third local oscillator optical splitter and enter the first polarization balanced detector 5123 and the second polarization balanced detector 5124 respectively. They are optically mixed with the light processed by the polarization rotation beam splitter 5121 and entering the receiving fiber coupling port 5111, thereby achieving signal demodulation processing.

[0328] After light from an external local oscillator (LO) light source enters the coherent chip, the specific splitting process is as follows: A certain proportion of the light (e.g., 40%) is split by an unbalanced optical splitter and enters the first polarization coherent modulator (PCM). This splitting ratio can be designed based on the power difference between the first and second polarization-differentiated transmitted light. The remaining 60% of the light enters the second LO optical splitter 5132. After passing through the second LO optical splitter 5132, the light is evenly split into two parts. One beam is connected to the second PCM 5152, and the other beam enters the third LO optical splitter 5133.

[0329] In actual chip design, the unbalanced optical splitter can be designed with different structures based on the difference in optical power output from the first polarization coherent modulator and the second polarization coherent modulator. This balances the power of the first and second polarization angles in the light beam emitted from the transmitting fiber coupling port 5113, thereby increasing the effective optical transmission power. This unbalanced optical splitter typically employs an optical splitter structure with an asymmetric waveguide structure.

[0330] The output end of the polarization rotation combiner 5141 is connected to the transmitting fiber coupling port 511 , the first input end is connected to the first polarization coherent modulator 5142 , and the second input end is connected to the second polarization coherent modulator 5152 .

[0331] In the example of this application, the unbalanced optical splitter can be designed by using an optical splitter structure with an asymmetric waveguide structure, or a device based on a Mach-Zehnder interference structure, such as Figure 46As shown in the figure, a heater is integrated above the Mach-Zehnder interferometer structure. Adjusting the heater can change the splitting ratio of the unbalanced beam splitter. In practice, the splitting ratio of the unbalanced beam splitter can be adjusted in real time based on the output optical power of the second polarization coherent modulator, ensuring that the power of the two polarizations in the light beam emitted from the transmit coupling port is balanced, thereby increasing the effective optical transmission power and improving chip yield.

[0332] Figure 48 This is a schematic diagram of the structure of an unbalanced optical splitter provided in an embodiment of the present application. Figure 48 As shown in , the unbalanced optical splitter includes: a first sub-splitting component, a modulation arm, an interference arm, and a second sub-splitting component, wherein the input end of the first sub-splitting component is connected to the local oscillator fiber coupling port to split the local oscillator light into two beams. The first output end of the first sub-splitting component is connected to the modulation arm, and the second output end is connected to the interference arm. The first input end of the third sub-splitting component is connected to the output end of the modulation arm, the second input end is connected to the output end of the interference arm, the first output end is connected to the input end of the second local oscillator optical splitter 5132, and the second output end is connected to the first polarization coherent modulator 5142. The MCU is electrically connected to the first modulation arm and the second modulation arm, and controls the temperature of the modulation arm by outputting a voltage to control the refractive index of the modulation arm, thereby realizing the splitting of the two output ends of the unbalanced optical splitter.

[0333] Figure 49 A schematic diagram of the coherent optical chip structure provided in this application Figure 6 In this example, the coherent optical chip further includes: a first transmit optical attenuator 5144 is provided in the coherent optical chip, which is disposed between the polarization rotation beam combiner 5141 and the first polarization coherent modulator to perform attenuation control on the first transmit signal light. To control the first transmit optical attenuator 5144, a first optical attenuator power monitor 5145 is provided at the first output end of the first transmit optical attenuator 5144, and the first output end of the first transmit optical attenuator 5144 is connected to the first input end of the transmit polarization rotation beam combiner 5141. The MCU is electrically connected to the first optical attenuator power monitor 5145, and controls the output voltage of the first transmit optical attenuator 5144 based on the data collected by the first optical attenuator power monitor 5145.

[0334] Figure 50 A schematic diagram of a coherent optical chip structure used in this application example Figure 7 ,like Figure 50As shown in FIG, to monitor the effective optical transmit power and calculate the splitting ratio of the unbalanced optical splitter, a first transmit power monitor 5147 is provided between the first transmit optical attenuator 5144 and the polarization rotation combiner 5141 in the coherent optical chip. This monitor is used to monitor the optical power of the attenuated first transmit signal light. The MCU is electrically connected to the first transmit power monitor 5147, and the host computer can read the optical power of the first transmit signal light stored in the MCU.

[0335] Similarly, to more accurately monitor the transmitted optical power, a second transmit power monitor is provided between the second transmit optical attenuator and the polarization rotation combiner 5141 to monitor the optical power of the attenuated second transmit signal light. The MCU is electrically connected to the second transmit power monitor, allowing the host computer to read the optical power of the second transmit signal light stored in the MCU.

[0336] The splitting ratio of the unbalanced optical splitter is regulated based on the data collected by the second transmission power monitor 5157 and the first transmission power monitor 5147 .

[0337] An unbalanced optical splitter can also utilize a device based on a Mach-Zehnder interferometer structure. A heater is integrated above the Mach-Zehnder interferometer structure, and adjustment of the heater can change the splitting ratio of the unbalanced optical splitter. In practice, the splitting ratio of the unbalanced optical splitter can be adjusted in real time based on the output optical power of the second polarization coherent modulator, ensuring that the power of the two polarized lights in the light beam emitted from the transmitting fiber coupling port 511 and the transmitting fiber coupling port 5115113 is balanced, thereby increasing the effective optical transmission power and improving chip yield.

[0338] In the coherent optical module of the present application example, the input end of the unbalanced optical splitter is connected to the local oscillator fiber coupling port 5112, the first output end is connected to the first polarization coherent modulator, and the second output end is connected to the input end of the second local oscillator optical splitter. The first output end of the second local oscillator optical splitter is connected to the second polarization coherent modulator, and the second output end is connected to the input end of the third local oscillator optical splitter. The first output end of the third local oscillator optical splitter is connected to the first polarization-balanced receiver 5123, and the second output end is connected to the second polarization-balanced receiver 5124.

[0339] Furthermore, to achieve optical power balance between the two different polarizations, the second local oscillator splitter 5132 is an adjustable splitter that can adjust the optical splitting of the adjustable splitter based on the difference in output optical power between the first and second polarization coherent modulators. When the output optical power of the first polarization coherent modulator is greater than the output optical power of the second polarization coherent modulator, the light output ratio of the second output end of the adjustable splitter is increased, thereby increasing the optical power of the second emitted light entering the second polarization coherent modulator, thereby reducing the difference in output optical power between the first and second polarization coherent modulators.

[0340] When the output optical power of the first polarization coherent modulator is less than the output optical power of the second polarization coherent modulator, the light output ratio of the second output end of the adjustable beam splitter is reduced. The optical power of the second emitted light entering the second polarization coherent modulator is reduced, thereby reducing the difference between the output optical power of the first polarization coherent modulator and the output optical power of the second polarization coherent modulator.

[0341] The above description is merely a specific embodiment of the present disclosure, but the scope of protection of the present disclosure is not limited thereto. Any changes or substitutions that a person skilled in the art can conceive within the technical scope disclosed in the present disclosure should be included within the scope of protection of the present disclosure. Therefore, the scope of protection of the present disclosure should be based on the scope of protection of the claims.

Claims

1. An optical module, characterized in that: include: The light source includes a first fixing frame, a second fixing frame, a base and an upper cover; The first fixing frame, the second fixing frame, the base and the upper cover body enclose a cavity; an optical component, located in the cavity, comprising a semiconductor gain chip and a silicon photonic chip; A silicon photonic chip is used to receive the light beam emitted by the semiconductor gain chip and filter a light beam of a specific wavelength from the light beam; Silicon photonic chips include: An input coupler, configured to receive a light beam emitted by the semiconductor gain chip and emit a light beam of a specific wavelength to the semiconductor gain chip; a directional coupler connected to the input coupler; A wavelength-tunable optical component for selecting a specific wavelength beam from a light beam; The wavelength sensor and the wavelength tunable optical component are both connected to the directional coupler; The fifth power monitor and the sixth power monitor are respectively connected to the wavelength sensor, and together with the wavelength sensor and the sixth power monitor, form a wavelength locking optical component, so that the wavelength locking optical component achieves wavelength locking according to the ratio of the optical power of the fifth monitoring detector to the optical power of the sixth monitoring detector; The wavelength sensor includes a first optical splitter, a first modulation arm, a second modulation arm, and a second optical splitter; The first optical splitter is connected to the directional coupler; The first modulation arm has a first end connected to the first optical splitter and a second end connected to the second optical splitter, and includes a silicon waveguide; The second modulation arm has a first end connected to the first optical splitter and a second end connected to the second optical splitter, and includes a silicon nitride waveguide; The second optical splitter is further connected to the fifth power monitor and the sixth power monitor respectively; A difference between a product of a length of the first modulation arm and a refractive index of the first modulation arm and a product of a length of the second modulation arm and a refractive index of the second modulation arm is a constant value.

2. The optical module according to claim 1, wherein The wavelength tunable optical component includes a phase modulator, a first power divider, a first filter and a second filter; The phase modulator is connected to the directional coupler via an optical waveguide; The first power splitter is connected to the phase modulator via an optical waveguide and is used for splitting and combining the light beams; The first filter is coupled to the power divider via a first straight optical waveguide; The second filter is coupled to the first filter via a second straight optical waveguide, is coupled to the first power divider via a third straight optical waveguide, and cooperates with the first filter to achieve screening of light beams of specific wavelengths.

3. The optical module according to claim 1, wherein: The silicon photonic chip further includes a fourth monitoring detector; The fourth monitoring detector is connected to the directional coupler via an optical waveguide and is used to monitor the optical power of a light beam with a specific wavelength so as to adjust the magnitude of the optical power coupled to the semiconductor gain chip.

4. The optical module according to claim 2, wherein: The silicon photonic chip further includes a first absorber, a second absorber, a third absorber and a fourth absorber; The first absorber is connected to the first straight optical waveguide and is used to absorb other light beams in the first straight optical waveguide except those that pass through the first filter and the second filter; The second absorber and the third absorber are respectively connected to two ends of the second straight optical waveguide, and are used to absorb other light beams in the second straight optical waveguide except those that pass through the first filter and the second filter; The fourth absorber is connected to the third straight optical waveguide and is used to absorb other light beams in the third straight optical waveguide except those that pass through the first filter and the second filter.

5. The optical module according to claim 1, wherein: Also includes: A first circuit board is provided with coherent components, a DSP chip and an optical fiber winding frame; a second circuit board, connected to the first circuit board via a third circuit board, and connected to the light source; a first supporting plate connected to the second circuit board; The third supporting plate is connected to the first supporting plate and the light source, so as to form a light source assembly with the first supporting plate, the second circuit board and the light source.

6. The optical module according to claim 5, characterized in that The optical fiber winding frame includes a first protrusion, a second protrusion and a third protrusion; The first protrusion is located at an end of the optical fiber winding frame away from the light source; The second protrusion is located between the first protrusion and the third protrusion, and a second storage groove is formed between the second protrusion and the first protrusion; The third protrusion is located at an end of the optical fiber winding frame close to the light source; The second storage groove is more recessed than the first storage groove and is provided with a protective cover to protect the fusion splicing point of the first optical fiber and the local oscillator optical fiber. The first protrusion, the second protrusion and the third protrusion are respectively connected to the side of the optical fiber winding rack to form the first storage groove. The optical fiber extending from the local oscillator optical interface of the coherent component is the local oscillator optical fiber, and the optical fiber extending from the light source is the first optical fiber.

7. The optical module according to claim 1, wherein: The light source is further provided with an internal fiber optic adapter, a first lens and a fifth lens; The first lens is located between the semiconductor gain chip and the internal optical fiber adapter; The fifth lens is located between the silicon photonic chip and the wavelength calibration component.

8. The optical module according to claim 7, wherein: The light source is further provided with a semiconductor amplifier chip; The semiconductor amplifier chip is located between the first lens and the optical fiber adapter, and is used to amplify the optical power of a light beam with a specific wavelength.

9. The optical module according to claim 8, wherein: The light source is further provided with a beam splitter and a first power monitor; The beam splitter is located between the semiconductor amplifier chip and the internal optical fiber adapter; The first power monitor is used to monitor the optical power of the light beam with a specific wavelength split by the beam splitter.

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