CN115712179A

CN115712179A - Optical module

Info

Publication number: CN115712179A
Application number: CN202211449403.5A
Authority: CN
Inventors: 隋少帅
Original assignee: Hisense Broadband Multimedia Technology Co Ltd
Current assignee: Hisense Broadband Multimedia Technology Co Ltd
Priority date: 2022-11-18
Filing date: 2022-11-18
Publication date: 2023-02-24

Abstract

The application discloses optical module includes: a coherent optical chip, comprising: a receiving optical fiber coupling port, a local oscillation optical fiber coupling port and a polarization rotation beam splitter; and the input end of the non-equilibrium optical splitter is connected with the local oscillator optical fiber coupling port, the first output end of the non-equilibrium optical splitter is connected with the first polarization coherent modulator, and the second output end of the non-equilibrium optical splitter is connected with the second local oscillator optical splitter. The output end of the second local oscillator optical splitter is connected with the second polarization coherent modulator and the third local oscillator optical splitter. The first polarization balance receiver of output end of third local oscillator optical splitter connects, the balanced receiver of second polarization connects. According to the method and the device, different structural designs can be performed on the light splitting proportion of the unbalanced light splitter according to the difference of the output light power of the first polarization coherent modulator and the output light power of the second polarization coherent modulator, so that the two polarized light powers of the first angle and the second angle in the light beam emitted from the emission optical fiber coupling port are balanced.

Description

Optical module

Technical Field

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

Background

In the optical communication, an optical module is a tool for realizing the interconversion of photoelectric signals, and is one of key devices in optical communication equipment, and along with the rapid development of a 5G network, the optical module in the core position of the optical communication is developed greatly.

The conventional optical communication system mainly adopts an intensity modulation/direct demodulation (IMDD) mode, in which the intensity of an optical carrier is directly modulated at a transmitting end, and an envelope detection is performed on the optical carrier at a receiving end. The mode has simple structure, low cost and wide application in modern communication systems, and has the disadvantages of single modulation format, limited bandwidth of single-channel and incapability of meeting the increasing bandwidth requirement. Coherent optical communication has the advantages of high receiving sensitivity, high spectrum efficiency, suitability for various modulation formats and the like, can effectively make up for the defect of direct demodulation of intensity modulation, can modulate information such as amplitude, frequency, phase and the like of an optical carrier through coherent demodulation, and promotes the development of an optical digital transmission system.

Disclosure of Invention

In the optical module provided by the application, the optical power of two beams of transmitting signal light with different polarization directions in the coherent optical module is improved to be the same.

The optical module provided by the embodiment of the application comprises: coherent optical chip, with fiber splice coupling connection, include:

a receiving optical fiber coupling port for receiving the receiving signal light;

the local oscillator optical fiber coupling port receives the local oscillator light;

the polarization rotation beam splitter is arranged on one side of the receiving optical fiber coupling port and used for splitting the received signal light into a first received signal light and a second received signal light according to different deflection angles;

the input end of the non-equilibrium optical splitter is connected with the local oscillation optical fiber coupling port, the first output end of the non-equilibrium optical splitter is connected with the first polarization coherent modulator, and the second output end of the non-equilibrium optical splitter is connected with the input end of the second local oscillation optical splitter;

the first output end of the second local oscillator optical splitter is connected with the second polarization coherent modulator, and the second output end of the second local oscillator optical splitter is connected with the input end connected with the third local oscillator optical splitter;

a first output end of the third local oscillator optical splitter is connected with the first polarization balance receiver, and a second output end of the third local oscillator optical splitter is connected with the second polarization balance receiver;

the optical power output by the first polarization coherent modulator is the same as that output by the second polarization coherent modulator;

the first polarization balance receiver is connected with the first output port of the polarization rotation beam splitter and the first output port of the third local oscillation beam splitter;

and the second polarization balance receiver is connected with the second output port of the polarization rotation beam splitter and the second output port of the third local oscillation beam splitter.

The beneficial effect of this application:

the application discloses optical module includes: a coherent optical chip, comprising: the system comprises a receiving optical fiber coupling port, a local oscillation optical fiber coupling port and a polarization rotation beam splitter; and the input end of the non-equilibrium optical splitter is connected with the local oscillation optical fiber coupling port, the first output end of the non-equilibrium optical splitter is connected with the first polarization coherent modulator, and the second output end of the non-equilibrium optical splitter is connected with the input end of the second local oscillation optical splitter. The first output end of the second local oscillator optical splitter is connected with the second polarization coherent modulator, and the second output end of the second local oscillator optical splitter is connected with the input end connected with the third local oscillator optical splitter. The first output end of the third local oscillator light splitter is connected with the first polarization balance receiver, and the second output end of the third local oscillator light splitter is connected with the second polarization balance receiver. And the first polarization balance receiver is connected with the first output port of the polarization rotation beam splitter and the first output port of the third local oscillation beam splitter. And the second polarization balance receiver is connected with a second output port of the polarization rotation beam splitter and a second output port of the third local oscillation beam splitter. According to the optical fiber coupling port emission device, different structural designs can be carried out on the light splitting proportion of the unbalanced light splitter according to the difference of the output optical power of the first polarization coherent modulator and the output optical power of the second polarization coherent modulator, so that the two polarized optical powers of the first angle and the second angle in the light beam emitted from the emission optical fiber coupling port are balanced, and the effective light emission power is improved.

Drawings

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

Fig. 1 is a connection diagram of an optical communication system;

FIG. 2 is a block diagram of an optical network terminal;

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

FIG. 4 is an exploded block diagram of a light module according to some embodiments;

FIG. 5 is a block diagram of an optical module with the housing and unlocking components removed according to some embodiments;

FIG. 6 is a diagram of a fiber optic adapter, light source, coherence assembly, and circuit board structure according to some embodiments;

FIG. 7 is an exploded block diagram of an optical module with the housing and unlocking components removed according to some embodiments;

FIG. 8 is a block diagram of a first angle of a fiber winding frame according to some embodiments;

FIG. 9 is a block diagram of a second angle of an optical fiber winding frame according to some embodiments;

FIG. 10 is a block diagram of a light source according to some embodiments;

FIG. 11 is an exploded view of a light source according to some embodiments;

fig. 12 is a block diagram of a first support plate according to some embodiments;

FIG. 13 is a block diagram of a first angle of a second support plate according to some embodiments;

FIG. 14 is a block diagram of a second angle of a second support plate according to some embodiments;

FIG. 15 is a block diagram of a second circuit board according to some embodiments;

FIG. 16 is a block diagram of a light source according to some embodiments;

FIG. 17 is an exploded view of a light source according to some embodiments;

FIG. 18 is a block diagram of a light source with the upper cover, optical assembly, and internal fiber optic adapter removed according to some embodiments;

FIG. 19 is an exploded view of a light source with the upper cover, optical assembly, and internal fiber optic adapter removed according to some embodiments;

FIG. 20 is a block diagram of a second mount according to some embodiments;

FIG. 21 is a block diagram of a first mount according to some embodiments;

FIG. 22 is a first cross-sectional view of a light source according to some embodiments;

FIG. 23 is a second cross-sectional view of a light source according to some embodiments;

FIG. 24 is a block diagram of a first light source according to some embodiments;

FIG. 25 is a block diagram of a second light source according to some embodiments;

FIG. 26 is a block diagram of a third light source according to some embodiments;

FIG. 27 is a block diagram of a fourth light source according to some embodiments;

FIG. 28 is a block diagram of a fifth light source according to some embodiments;

FIG. 29 is a block diagram of a first type of silicon photonics chip in accordance with some embodiments;

FIG. 30 is a filter graph of a wavelength sensor according to some embodiments;

FIG. 31 is a block diagram of a sixth light source according to some embodiments;

FIG. 32 is a block diagram of a second type of silicon photonics chip in accordance with some embodiments;

FIG. 33 is a block diagram of a third silicon photonics chip in accordance with some embodiments;

FIG. 34 illustrates a coherent component according to an embodiment of the present application;

FIG. 35 is an exploded view of a coherent component according to an embodiment of the present application;

fig. 36 is a schematic diagram of a carrier structure according to an example of the present application;

FIG. 37 is a first schematic structural view of a cover shell according to an example of the present application;

FIG. 38 is a second structural schematic view of a cover shell of the present example of application;

FIG. 39 is a cross-sectional view of an exemplary fiber optic splice and coherence assembly of the present application;

FIG. 40 is a first schematic structural view of an exemplary fiber mount of the present application;

FIG. 41 is a second schematic structural view of an optical fiber securing member;

FIG. 42 is a schematic diagram of an exemplary coherent optical chip;

FIG. 43 is a second schematic structural diagram of a coherent optical chip according to an example of the present application;

FIG. 44 is a schematic diagram of a layout of optical chip with embedded balls on the surface of the chip according to the present embodiment;

fig. 45 is a schematic structural diagram of a coherent optical chip provided in the present application;

fig. 46 is a schematic structural diagram of a coherent optical chip according to the present application;

fig. 47 is a schematic structural diagram of a coherent optical chip according to the present application;

fig. 48 is a schematic structural diagram of an unbalanced splitter according to an embodiment of the present disclosure;

FIG. 49 is a sixth schematic diagram illustrating an exemplary coherent optical chip according to the present application;

fig. 50 is a schematic diagram of a coherent optical chip according to an example of the present application.

Detailed Description

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

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

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

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

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

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

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

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

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

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

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

Fig. 3 is a block diagram of a light module according to some embodiments. FIG. 4 is an exploded block diagram of a light module according to some embodiments. FIG. 5 is a patterning of an optical module with the housing and unlocking member removed according to some embodiments. FIG. 6 is a block diagram of a fiber optic adapter, light source, coherence assembly, and circuit board, according to some embodiments. As shown in fig. 3-6, the optical module 200 includes a housing (shell), a circuit board 300 disposed within the housing, a light source 401, a coherent component 500, a DSP chip 600, and a fiber optic winding frame 700.

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

In some embodiments of the present disclosure, the lower housing 202 includes a bottom plate 2021 and two lower side plates 2022 located at both sides of the bottom plate 2021 and disposed perpendicular to the bottom plate 2021; the upper case 201 includes a cover 2011, and the cover 2011 covers the two lower side plates 2022 of the lower case 202 to form the above case.

In some embodiments, the lower housing 202 includes a bottom plate 2021 and two lower side plates 2022 located at both sides of the bottom plate 2021 and disposed perpendicular to the bottom plate 2021; the upper housing 201 includes a cover 2011 and two upper side plates located on two sides of the cover 2011 and perpendicular to the cover 2011, and the two upper side plates are combined with the two lower side plates 2022 to cover the upper housing 201 on the lower housing 202.

The direction of the connecting line of the two

openings

204 and 205 may be the same as the length direction of the optical module 200, or may not be the same as the length direction of the optical module 200. For example, the opening 204 is located at an end portion (right end in fig. 3) of the optical module 200, and the opening 205 is also located at an end portion (left end in fig. 3) of the optical module 200. Alternatively, the opening 204 is located at an end of the optical module 200, and the opening 205 is located at a side of the optical module 200. The opening 204 is an electrical port, and a gold finger of the circuit board 300 extends out of the electrical port 204 and is inserted into an upper computer (for example, the optical network terminal 100); the opening 205 is an optical port configured to receive the external optical fiber 101 so that the external optical fiber 101 is connected to the light source 401 inside the optical module 200.

The upper shell 201 and the lower shell 202 are combined in an assembly mode, so that the circuit board 300, the light source 401 and other devices can be conveniently installed in the shells, and the upper shell 201 and the lower shell 202 form packaging protection for the devices. In addition, when the devices such as the circuit board 300 and the light source 401 are assembled, the positioning components, the heat dissipation components and the electromagnetic shielding components of the devices are convenient to arrange, and the automatic production is facilitated.

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

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

Illustratively, the unlocking member is located on the outer wall of the two lower side plates 2022 of the lower housing 202, and has a snap-fit member that matches with a cage of the upper computer (e.g., the cage 106 of the optical network terminal 100). When the optical module 200 is inserted into the cage of the upper computer, the optical module 200 is fixed in the cage of the upper computer by the engaging member of the unlocking member; when the unlocking member is pulled, the engaging member of the unlocking member moves along with the unlocking member, and further the connection relationship between the engaging member and the upper computer is changed, so that the engagement relationship between the optical module 200 and the upper computer is released, and the optical module 200 can be drawn out from the cage of the upper computer.

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

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

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

Of course, a flexible circuit board is also used in some optical modules. Flexible circuit boards are commonly used in conjunction with rigid circuit boards to supplement the rigid circuit boards. For example, a rigid circuit board may be connected to the light source by a flexible circuit board.

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, the third circuit board 303 is a flexible circuit board, the second circuit board 302 is stacked 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 housing 201, and the first circuit board 301 and the second circuit board 302 are connected through the third circuit board 303.

And the light source 401 is connected with the second circuit board 302 and is used for emitting a preset light beam with a specific wavelength. Specifically, the light source 401 includes a semiconductor gain chip and a silicon optical chip, the semiconductor gain chip emits a light beam in a wavelength range, the silicon optical chip screens out a light beam with a specific wavelength from the light beam in the wavelength range, the silicon optical chip and the semiconductor gain chip form a resonant cavity, the light beam with the specific wavelength is reflected back and forth between the silicon optical chip and the semiconductor gain chip, and the light beam with the specific wavelength is stably output by the semiconductor gain chip.

The optical module also includes a transmit fiber optic adapter 800 and a receive fiber optic adapter 801. The transmitting fiber adapter 800 is used for transmitting high-speed optical signals, and the receiving fiber adapter 801 is used for receiving high-speed optical signals.

And the coherent component 500 is arranged on the circuit board and used for realizing the conversion of the high-speed photoelectric signal. Specifically, the coherent component 500 includes an optical transmission interface, an optical reception interface, and a local oscillator optical interface, where the optical transmission interface extends out of the first optical fiber, the optical reception interface extends out of the second optical fiber, the local oscillator optical interface extends out of the third optical fiber, the optical transmission interface is connected to the transmission optical fiber adapter 800, the optical reception interface is connected to the reception optical fiber adapter 801, and the local oscillator optical interface is connected to the light source 401. The coherent component is connected with the transmitting optical fiber adapter, the receiving optical fiber adapter and the light source 401 through the optical transmitting interface, the optical receiving interface and the local oscillation optical interface respectively, and the coherent component 500 is further connected with the DSP chip 600.

Narrow-linewidth and high-power laser emitted by a light source 401 is input into a coherent assembly 500 through a local oscillation optical interface, and the laser is subjected to beam splitting processing inside the coherent assembly 500, wherein one laser beam is used as a transmission light beam and enters a coherent modulator inside the coherent assembly, electro-optical signal conversion is realized under the driving of a high-speed electric signal of a DSP chip 600, and the converted high-speed optical signal is output from an optical transmission interface of the module; the other beam is used as a local oscillator beam to perform coherent demodulation with a high-speed optical signal input into the coherent component 500 from the module optical receiving port, and the demodulated electrical signal enters the DSP chip 600 to perform signal processing, thereby completing the photoelectric signal conversion. Wherein the narrow linewidth and high power laser is a specific wavelength beam.

Light source 401 still includes inside optic fibre adapter, and inside optic fibre adapter stretches out first optic fibre, and local oscillator optical interface stretches out local oscillator optic fibre, first optic fibre and local oscillator optical fiber welded connection to make inside optic fibre adapter and local oscillator optical interface connection. The launch fiber optic adapter 800 extends out of a second optical fiber, the light launch interface extends out of the launch fiber, and the second optical fiber is fusion spliced to the launch fiber such that the launch fiber optic adapter 800 is connected to the light launch interface. The receiving fiber adapter 801 extends out of a third optical fiber, the light receiving interface extends out of the receiving fiber, and the third optical fiber is fusion-spliced with the receiving fiber, so that the receiving fiber adapter 801 is connected with the light receiving interface.

Because there is certain failure rate during the butt fusion of two optic fibres, in order to guarantee two optic fibres are last to be welded successfully, need reserve certain optic fibre length to two optic fibres can continue the butt fusion after the butt fusion fails. And because the connection point of the first optical fiber and the local oscillator optical fiber in fusion connection is located near the internal optical fiber adapter, the connection point of the second optical fiber and the transmitting optical fiber in fusion connection is located near the transmitting optical fiber adapter 800, and the connection point of the third optical fiber and the receiving optical fiber in fusion connection is located near the receiving optical fiber adapter 801, the lengths of the first optical fiber, the local oscillator optical fiber, the transmitting optical fiber and the receiving optical fiber are longer.

And an optical fiber winding frame 700 for fixing the optical fiber. Specifically, since the circuit board 300 is provided with high-frequency signal lines and many devices, the optical fiber cannot be directly laid on the surface of the circuit board 300. Since the lengths of the first optical fiber, the local oscillation optical fiber, the transmitting optical fiber, and the receiving optical fiber are long, in order to prevent the upper case from being damaged by pressure, an optical fiber winding frame 700 for fixing the optical fibers is provided between the coherent module 500 and the upper case 201.

First optic fibre, local oscillator optic fibre, emission optic fibre and receipt optic fibre all neatly are fixed in on optic fibre winding frame 700, have not only avoided first optic fibre of upper casing pressure loss, local oscillator optic fibre, emission optic fibre and receiving optical fiber, have still avoided the direct signal crosstalk problem that causes of laying on the surface of circuit board 300 of optic fibre.

FIG. 8 is a block diagram of a first angle of a fiber winding frame according to some embodiments. Fig. 9 is a block diagram of a second angle of an optical fiber winding frame according to some embodiments. As shown in fig. 4 to 9, in some embodiments, the optical fiber winding frame 700 includes two first support legs 701 and two second support legs 702, the first support legs 701 are engaged with the engaging interface of the first circuit board 301, 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 disposed on two sides of the optical fiber winding frame 700, the two second support legs 702 are symmetrically disposed on two sides of the optical fiber winding frame 700, and the second support legs 702 are closer to the light source 401 than the first support legs 701.

As seen in fig. 4-9, in some embodiments, the outer surface of the fiber optic spool 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 an end of the fiber winding frame 700 away from the light source 401, and the third protrusion 705, the fourth protrusion 706, and the fifth protrusion 707 are located at an end of the fiber winding frame 700 close to the light source 401. First article placing grooves are respectively formed 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 edge of the optical fiber winding frame 700, a second article placing groove 708 is formed between the first protrusion 703 and the second protrusion 704, the article placing grooves between any two protrusions except the first protrusion 703 and the second protrusion 704 in all the protrusions are the first article placing grooves, and the second article placing groove 708 is more concave relative to the first article placing grooves.

The local oscillator fiber, the transmitting fiber, and the receiving fiber all extend out of the coherent assembly 500 through the coherent assembly 500, and extend into the fiber winding frame 700 through the fourth protrusion 706 and the first accommodating slot between the lateral sides of the fiber winding frame 700.

The local oscillation optical fiber sequentially passes through the first object placing groove between the first protrusion 703 and the side edge of the optical fiber winding frame 700 → the first object placing groove between the second protrusion 704 and the side edge of the optical fiber winding frame 700 → the first object placing groove between the third protrusion 705 and the fifth protrusion 707 → the first object placing groove between the third protrusion 705 and the fourth protrusion 706 → the second object placing groove 708 between the second protrusion 704 and the first protrusion 703.

The local oscillation fiber may also pass through the first object placing groove between the third protrusion 705 and the fourth protrusion 706, the first object placing groove between the second protrusion 704 and the third protrusion 705 → the first object placing groove between the third protrusion 705 and the fifth protrusion 707 → the first object placing groove between the third protrusion 705 and the fourth protrusion 706 → the first object placing groove between the third protrusion 705 and the side of the fiber winding frame 700 → the second object placing groove 708 between the second protrusion 704 and the first protrusion 703.

The first time optical fiber passes through the first placement groove between the fourth protrusion 706 and the side of the optical fiber winding frame 700 → the first placement groove between the third protrusion 705 and the side of the optical fiber winding frame 700 → the first placement groove between the first protrusion 703 and the side of the optical fiber winding frame 700 → the first placement groove between the second protrusion 704 and the side of the optical fiber winding frame 700 → the first placement groove between the third protrusion 705 and the fifth protrusion 707 → the first placement groove between the third protrusion 705 and the fourth protrusion 706 → the first placement groove between the second protrusion 704 and the third protrusion 705 → the first placement groove between the third protrusion 707 and the fifth protrusion → the first placement groove between the third protrusion 705 and the fourth protrusion 706 → the first placement groove between the third protrusion 705 and the side of the optical fiber winding frame 700 → the first placement groove between the first protrusion 704 and the second protrusion 703 → the first placement groove between the first protrusion 703 and the side of the optical fiber winding frame 700 → the second protrusion 703.

The emission optical fiber sequentially passes through the first object placing groove between the first protrusion 703 and the side edge of the optical fiber winding frame 700 → the first object placing groove between the second protrusion 704 and the side edge of the optical fiber winding frame 700 → the third protrusion 705 and the first object placing groove between the side edges of the optical fiber winding frame 700, and then extends out of the optical fiber winding frame 700 through the first object placing groove between the fifth protrusion 707 and the side edge of the optical fiber winding frame 700, and is connected with the second optical fiber in a fusion manner near the emission optical fiber adapter 800.

The received optical fiber sequentially passes through the first object placing groove between the first protrusion 703 and the side edge of the optical fiber winding frame 700 → the first object placing groove between the second protrusion 704 and the side edge of the optical fiber winding frame 700 → the first object placing groove between the third protrusion 705 and the side edge of the optical fiber winding frame 700 → the first object placing groove between the fifth protrusion 707 and the third protrusion 705, and then extends out of the optical fiber winding frame 700 through the first object placing groove between the fourth protrusion 706 and the fifth protrusion 707, and is connected with the third optical fiber in a fusion mode near the received optical fiber adapter 801.

As can be seen from the above description, the fusion splice point of the first optical fiber and the local oscillator fiber is located in the second accommodating slot 708. In order to protect the fusion-splicing point of the first optical fiber and the local oscillator optical fiber, in some embodiments, a protective sleeve is disposed in the second object placing groove 708, and the protective sleeve is used for protecting the fusion-splicing point of the first optical fiber and the local oscillator optical fiber and preventing the fusion-splicing point of the first optical fiber and the local oscillator optical fiber from being broken.

Because the fusion splicing point of the first optical fiber and the local oscillator optical fiber is located in the second storage slot 708, in order to increase the number of times that the first optical fiber and the local oscillator optical fiber can be fused, so as to ensure successful fusion splicing, the third protrusion 705 is shaped as a cylinder, and the circumference of the third protrusion 705 is smaller than (the sum of the lengths of the first storage slot between the sides of the first protrusion 703 and the optical fiber winding frame 700, the first storage slot between the sides of the second protrusion 704 and the optical fiber winding frame 700, and the first storage slot between the sides of the third protrusion 705 and the optical fiber winding frame 700).

When the optical fiber is not wound along the third protrusion 705, when the first optical fiber and the local oscillator optical fiber are failed in fusion splicing and need to be fused again, the length of the first optical fiber or the local oscillator optical fiber which needs to be cut off is the length of the first optical fiber or the local oscillator optical fiber which winds the whole fiber winding frame 700 in a circle. After the optical fiber is wound around the third protrusion 705, when the first optical fiber and the local oscillation optical fiber are failed in fusion splicing and need to be fused again, the length of the first optical fiber or the local oscillation optical fiber which needs to be cut off is the length of the first optical fiber or the local oscillation optical fiber which winds around the third protrusion 705 for a circle.

For example, when the third protrusion 705 is not provided, and fusion splicing of the first optical fiber and the local oscillation optical fiber fails and needs to be performed again, the length of the first optical fiber to be cut may be 100 mm; when the third protrusion 705 is provided, and fusion splicing of the first optical fiber and the local oscillation optical fiber fails and needs to be performed again, the length of the first optical fiber to be cut may be 50 mm.

In order to fix the first optical fiber, the local oscillator optical fiber, the transmitting optical fiber and the receiving optical fiber in the optical fiber winding frame 700, a plurality of protrusions of the optical fiber winding frame 700 and the side edge of the optical fiber winding frame 700 are provided with clamping strips, one end of each clamping strip is connected with the surface of the protrusion of the optical fiber winding frame 700, and the other end of each clamping strip is connected with the surface of the side edge of the optical fiber winding frame 700.

Due to the existence of the clamping strips, the first optical fiber, the local oscillation optical fiber, the transmitting optical fiber and the receiving optical fiber are fixed in the optical fiber winding frame 700, and optical fiber damage caused by the fact that the first optical fiber, the local oscillation optical fiber, the transmitting optical fiber and the receiving optical fiber are separated from the optical fiber winding frame 700 is avoided.

As shown in fig. 4-9, in some embodiments, the inner surface of the optical fiber winding frame 700 is provided with a third placing groove 709 and a fourth placing groove 710, both the third placing groove 709 and the fourth placing groove 710 are formed by inward recessing of the inner surface of the optical fiber winding frame 700, the third placing groove 709 is recessed relative to the fourth placing groove 710, the third placing groove 709 is located at an end of the optical fiber winding frame 700 close to the light source 401, and the fourth placing groove 710 is located at an end of the optical fiber winding frame 700 far from the light source 401. The third housing 709 is used for housing the coherent component 500, and the fourth housing 710 is used for housing the DSP chip 600. Wherein, the shape of the third object holding groove 709 is the same as the shape of the coherent component 500.

As can be seen in fig. 4-9, in some embodiments, the inner surface of the optical fiber winding frame 700 is further provided with a fifth accommodating groove 711. The fifth housing groove 711 is closer to the light source 401 than the third housing groove 709, the fifth housing groove 711 is used for placing the interface of the coherent component 500, and the third housing groove 709 is more concave than the fifth housing groove 711.

FIG. 10 is a block diagram of a light source according to some embodiments. Fig. 11 is an exploded view of a light source according to some embodiments. Fig. 12 is a block diagram of a first support plate according to some embodiments. Fig. 13 is a block diagram of a first angle of a second support plate according to some embodiments. Fig. 14 is a block diagram of a second angle of a second support plate according to some embodiments. FIG. 15 is a block diagram of a second circuit board according to some embodiments. As can be seen in fig. 4-15, in some embodiments, 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. In particular, the method comprises the following steps of,

the side of the light source 401 is provided with a plurality of metal pins, the side of the second circuit board 302 is provided with a plurality of pin pads, the metal pins and the pin pads are correspondingly arranged, and the light source 401 and the second circuit board 302 are electrically connected through the metal pins and the pin pads.

The second circuit board 302 is provided with two first through holes 3022, the second support plate 403 is provided with two second through holes 4032, the first through holes 3022 and the second through holes 4032 are correspondingly arranged, and the first through holes 3022 and the second through holes 4032 are connected by screws, so that the second circuit board 302 and the second support plate 403 are connected.

The second support plate 403 is further provided with a third through hole 4033, 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 correspondingly arranged, and the third through hole 4033 is connected with the fourth through hole 4024 through screws, so that the first support plate 402 is connected with the second support plate 403.

A fifth through hole 4031 is further formed in the second support plate 403, the fifth through hole 4031 is arranged in correspondence to the through hole on the cover plate 2011 of the upper housing 201, and the fifth through hole 4031 is connected to the through hole on the cover plate 2011 of the upper housing 201 through a screw, so that the second support plate 403 is connected to the upper housing 201.

The first supporting plate 402 is further provided with a supporting plate body 4022, a first supporting protrusion 4021 and a second supporting protrusion 4023, the first supporting protrusion 4021 and the second supporting protrusion 4023 are obtained by upward protruding of the supporting plate body 4022, the first supporting protrusion 4021 protrudes relative to the second supporting protrusion 4023, the first supporting protrusion 4021 is provided with a fourth through hole 4024, and the second supporting protrusion 4023 is connected with the lower surface of the light source 401.

The second supporting protrusions 4023 are heat dissipation glue. The presence of the heat-dissipating glue not only connects the light source 401 with the first support plate 402, but also dissipates heat of the light source 401.

The second support plate 403 is further provided with a sixth storage tray 4034 and a seventh storage tray 4035. Sixth object holding groove 4034 and seventh object holding groove 4035 are formed by inward depression of the inner surface of second support plate 403, sixth object holding groove 4034 and seventh object holding groove 4035 are communicated, sixth object holding groove 4034 is connected with second circuit board 302, and seventh object holding groove 4035 is connected with the upper surface of light source 401.

A first notch 3021 is disposed on a side of the second circuit board 302 facing the light source 401, and a plurality of pin pads are disposed on a side of the first notch 3021. The first opening 3021 is configured to receive the first support plate 402 and the light source 401 therein, and the first opening 3021 has a length dimension greater than a length dimension of the light source 401.

As can be seen in fig. 4-15, in some embodiments, the light source assembly 400 further includes a heat sink 404. A heat sink 404, disposed between the cover 2011 of the upper housing 201 and the second support plate 403, for dissipating heat of the light source assembly 400 out of the light module through the upper housing 201.

The wavelength of the existing light source is adjustable by combining a semiconductor gain chip and a separation filter. However, since a plurality of discrete components need to be coupled and packaged in the light source and the discrete components occupy a large space, the current light source has a large size and cannot meet the production requirements.

To address this issue, in some embodiments, a light source is presented. The light source includes a semiconductor gain chip for emitting a light beam of a range of wavelengths and a silicon photo chip. The silicon optical chip is internally integrated with a wavelength tunable optical component and a wavelength locking optical component, and the wavelength tunable optical component is used for screening out a light beam with a specific wavelength from light beams in a wavelength range emitted by the semiconductor gain chip so as to realize a wavelength tunable function; the wavelength locking optical assembly is used for judging whether the specific wavelength light beam deviates from the preset wavelength light beam or not so as to realize the wavelength locking function. If the specific wavelength light beam deviates from the preset wavelength light beam, the specific wavelength light beam screened by the wavelength tunable light assembly does not deviate from the preset wavelength light beam by adjusting the refractive index of the wavelength tunable light assembly. The semiconductor gain chip and the silicon optical chip form a resonant cavity, and the light beam with the specific wavelength is reflected back and forth between the semiconductor gain chip and the silicon optical chip, so that the light beam with the specific wavelength is stably output by the semiconductor gain chip. The silicon optical chip is internally integrated with a wavelength tunable optical component and a wavelength locking optical component, so that the light source can realize the functions of wavelength tuning and wavelength locking; space is also saved, so that the size of the light source is smaller to meet the production requirement.

FIG. 16 is a block diagram of a light source according to some embodiments. FIG. 17 is an exploded view of a light source according to some embodiments. FIG. 18 is a block diagram of a light source with the upper cover, optical assembly, and internal fiber optic adapter removed according to some embodiments. FIG. 19 is an exploded view of a light source with the upper cover, optical assembly, and internal fiber optic adapter removed according to some embodiments. Fig. 20 is a block diagram of a second mount according to some embodiments. FIG. 21 is a block diagram of a first mount according to some embodiments. Fig. 22 is a first cross-sectional view of a light source according to some embodiments. FIG. 23 is a second cross-sectional view of a light source according to some embodiments. As seen in fig. 4-23, in some embodiments, light source 401 includes a first mount 4011, a second mount 4012, an upper cover 4013, a base 4014, and an internal fiber optic adapter 4016. First mount 4011 is provided with second breach 40111 and patchhole 40112, and second breach 40111 and patchhole 40112 are located first mount 4011's both ends respectively, and second mount 4012 joint is in first mount 4011's second breach 40111 department, and inside optic fibre adapter 4016 places in patchhole 40112. A plurality of metal pins 4015 are disposed on a surface of the second fixing frame 4012 close to the second circuit board 302. A plurality of metal pins 4015 are soldered to a plurality of pin pads on second circuit board 302. The first and second fixing frames 4011 and 4012, the upper cover 4013 and the base 4014 enclose a cavity, and the optical assembly 405 is disposed in the cavity.

As can be seen in fig. 4-23, in some embodiments, two semiconductor refrigerators 40141 are disposed on base 4014, ceramic substrates 40142 are disposed on two semiconductor refrigerators 40141, and optical assemblies 405 are disposed on ceramic substrates 40142. The optical assembly 405 is placed on a ceramic substrate 40142 to facilitate temperature control of the optical assembly 405.

As seen in fig. 4-23, in some embodiments, the optical assembly 405 includes a semiconductor gain chip 4051, a silicon optical chip 4052, a first lens 4053, an isolator 4054, a second lens 4055, a semiconductor amplification chip 4056, a third lens 4057, a beam splitter 4058, a first power monitor 4059, and a fourth lens 4060. In particular, the method comprises the following steps of,

a semiconductor gain chip 4051 is positioned between the fourth lens 4060 and the first lens 4053 for emitting a range of wavelengths of the light beam. A silicon optical chip 4052, located on one side of the fourth lens 4060, for receiving the light beams of one wavelength range and screening out light beams of a specific wavelength from the light beams of one wavelength range; and also for injecting a wavelength specific beam into the semiconductor gain chip 4051. The silicon optical chip 4052 and the semiconductor gain chip 4051 form a resonant cavity, and the light beam with the specific wavelength is reflected back and forth between the silicon optical chip 4052 and the semiconductor gain chip 4051, so that the light beam with the specific wavelength is stably output by the semiconductor gain chip.

Silicon photonics 4052 is used to screen out a particular wavelength beam from a range of wavelengths. Specifically, a wavelength tunable optical component and a wavelength locking optical component are integrated in the silicon optical chip 4052, and the wavelength tunable optical component is used for screening out a light beam with a specific wavelength from light beams in a wavelength range emitted by the semiconductor gain chip so as to realize a wavelength tunable function; the wavelength locking optical assembly is used for judging whether the specific wavelength light beam deviates from a preset wavelength light beam or not so as to realize the wavelength locking function. If the specific wavelength light beam deviates from the preset wavelength light beam, the specific wavelength light beam screened by the wavelength tunable light component does not deviate from the preset wavelength light beam by adjusting the refractive index of the wavelength tunable light component. The semiconductor gain chip and the silicon optical chip form a resonant cavity, and the light beam with the specific wavelength is reflected back and forth between the semiconductor gain chip and the silicon optical chip, so that the light beam with the specific wavelength is stably output by the semiconductor gain chip. The silicon optical chip is internally integrated with a wavelength tunable optical component and a wavelength locking optical component, so that the light source can realize the functions of wavelength tuning and wavelength locking; space is also saved, so that the size of the light source is smaller to meet the production requirement.

A first lens 4053 is positioned between the semiconductor gain chip 4051 and the isolator 4054 for collimating the wavelength-specific light beam. Specifically, the first lens 4053 is a collimating lens, and the collimating lens collimates the light beam with a specific wavelength.

And an isolator 4054, located between the first lens 4053 and the second lens 4055, for preventing the light beam incident on the second lens 4055 from being reflected back into the semiconductor gain chip 4051, so as to reduce the influence caused by the reflection of the light path, thereby reducing the noise level of the light source assembly 400.

And a second lens 4055, which is located between the isolator 4054 and the semiconductor amplification chip 4056, for converging and coupling the wavelength-specific light beam passing through the isolator 4054 into the semiconductor amplification chip 4056. Specifically, the second lens 4055 is a converging lens, and the converging lens converges and couples the light beam with the specific wavelength, which passes through the isolator 4054, into the semiconductor amplification chip 4056.

And a semiconductor amplifying chip 4056, which is located between the collimating lens 4057 and the third lens 4057, for performing power amplification on the light beam with the specific wavelength to increase the optical power of the light beam with the specific wavelength.

Since the semiconductor amplification 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 amplification chip 4056 is much higher than the optical power of the light beam emitted by the light source not provided with the semiconductor amplification chip 4056.

A third lens 4057 is positioned between the semiconductor amplifying chip 4056 and the beam splitter 4058 for collimating the light beam of the specific wavelength. Specifically, the third lens 4057 is a collimating lens, and the collimating lens collimates the light beam with the specific wavelength amplified by the semiconductor amplifying chip 4056.

A beam splitter 4058, located between the third lens 4057 and the internal fiber adapter 4016, for splitting the specific wavelength light beam into two paths, one path coupled to the first power monitor 4059 and one path coupled to the internal fiber adapter 4016.

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

And a first power monitor 4059, located between the beam splitter 4058 and the second fixing frame 4012, for monitoring the optical power of the light beam with a specific wavelength in real time. Specifically, when the optical power of the light beam with the specific wavelength is smaller than the preset optical power range, the amplification factor of the semiconductor amplification chip 4056 is increased so that the optical power of the light beam with the specific wavelength is within the preset optical power range. When the optical power of the light beam with the specific wavelength is greater than the predetermined optical power range, the amplification factor of the semiconductor amplification chip 4056 is reduced so that the optical power of the light beam with the specific wavelength is within the predetermined optical power range.

In some embodiments, the optical power of the specific wavelength light beam is monitored and adjusted in real time by the first power monitor 4059 so that the optical power of the specific wavelength light beam emitted by the light source is within a preset optical power range.

A fourth lens 4060 is positioned between the semiconductor gain chip 4051 and the silicon optical chip 4052 for collimating the light beam of one wavelength range output by the semiconductor gain chip 4051.

As can be seen in fig. 4-23, in some embodiments, a sixth lens 40161 and an optical window 40162 are disposed within internal fiber optic adapter 4016. The light window 40162 is closer to the beam splitter 4058 than the sixth lens 40161. The light beam with the specific wavelength is split into two paths by the beam splitter 4058, one path enters the internal fiber adapter 4016 through the optical window 40162, and is focused and coupled into the fiber plug core of the internal fiber adapter 4016 through the sixth lens 40161.

The optical package 405 can be divided into the following types according to the descriptions of the optical package 405 and the internal fiber optic adapter 4016 described above.

FIG. 24 is an optical path diagram of a first optical assembly according to some embodiments. As can be seen in fig. 24, in some embodiments, the optical assembly 405 includes a semiconductor gain chip 4051, a silicon optical chip 4052, and a first lens 4053, the semiconductor gain chip 4051 being positioned between the silicon optical chip 4052 and the first lens 4053, and the first lens 4053 being positioned between the semiconductor gain chip 4051 and the internal fiber adapter.

The other components except the silicon optical chip 4052 in the light source are all placed on one side of the silicon optical chip 4052, so that the space of the light source is effectively saved, the size of the light source is smaller, and the light source can meet the production requirement more easily.

Semiconductor gain chip 4051 is configured to emit a range of wavelengths of light. The silicon optical chip 4052 is used for receiving light beams in a wavelength range and screening light beams with specific wavelengths from the light beams in the wavelength range; and also for directing a specific wavelength beam into the semiconductor gain chip 4051. The semiconductor gain chip 4051 and the silicon optical chip 4052 form a resonant cavity, and the light beam with the specific wavelength is reflected back and forth between the semiconductor gain chip 4051 and the silicon optical chip 4052, so that the light beam with the specific wavelength is stably output by the semiconductor gain chip. The first lens 4053 is used to couple the wavelength-specific optical beam emitted by the semiconductor gain chip 4051 into the internal fiber adapter.

The semiconductor gain chip 4051 and the silicon optical chip 4052 form a resonant cavity, and the light beam with the specific wavelength is reflected back and forth between the semiconductor gain chip 4051 and the silicon optical chip 4052, so that the light beam with the specific wavelength is stably output by the semiconductor gain chip. Specifically, the semiconductor gain chip is processed by using III-V group gain materials and comprises two optical waveguide end faces, wherein one end face adopts an inclined waveguide structure and is plated with an antireflection film so as to realize extremely low optical field reflectivity, and the optical waveguide end face is used for being coupled with an input coupler of a silicon optical chip and facilitating the back and forth reflection of a light beam with a specific wavelength between the semiconductor gain chip and the silicon optical chip; the other end face adopts a straight waveguide structure and is plated with a reflecting film with certain reflectivity to realize the functions of light field reflection and transmission, so that the semiconductor gain chip 4051 can conveniently emit the light beam with the specific wavelength when the light beam with the specific wavelength oscillates to a certain degree.

FIG. 25 is an optical path diagram of a second optical assembly according to some embodiments. As can be seen in fig. 25, in some embodiments, the optical assembly 405 further includes an isolator 4054 and a second lens 4055, the isolator 4054 being located between the first lens 4053 and the second lens 4055, and the second lens 4055 being located between the isolator 4054 and the internal fiber adapter 4016.

FIG. 26 is an optical path diagram of a third optical assembly according to some embodiments. As can be seen in fig. 26, in some embodiments, the optical assembly 405 further includes a semiconductor magnifying chip 4056 and a third lens 4057, the semiconductor magnifying chip 4056 being located between the second lens 4055 and the third lens 4057, and the third lens 4057 being located between the semiconductor magnifying chip 4056 and the internal optical fiber fitting 4016.

FIG. 27 is an optical path diagram of a fourth optical assembly according to some embodiments. As can be seen in fig. 27, in some embodiments, the optical assembly 405 further includes a beam splitter 4058 and a first power monitor 4059, the beam splitter 4058 being located between the third lens 4057 and the internal fiber fitting 4016, the first power monitor 4059 being located on one side of the beam splitter 4058.

FIG. 28 is an optical path diagram of a fifth optical component according to some embodiments. As can be seen in fig. 27, in some embodiments, the optical assembly 405 further includes a fourth lens 4060, the fourth lens 4060 is positioned between the semiconductor gain chip 4051 and the silicon optical chip 4052, and the semiconductor gain chip 4051 is positioned between the fourth lens 4060 and the first lens 4053.

FIG. 29 is a block diagram of a first type of silicon photonics chip in accordance with some embodiments. FIG. 30 is a filter graph of a wavelength sensor according to some embodiments. As seen in fig. 29-30, in some embodiments, the first type of 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 divider 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 a silicon optical chip processed by a CMOS process. In particular, the method comprises the following steps of,

and an input coupler 40521, disposed at an end face of the silicon optical chip 4052, for receiving the light beam of one wavelength range emitted from the semiconductor gain chip 4051, and outputting the light beam of a specific wavelength screened by the silicon optical chip 4052 to the outside of the silicon optical chip 4052.

The light beam with the specific wavelength is reflected back and forth between the silicon optical chip 4052 and the semiconductor gain chip 4051, so that the semiconductor gain chip 4051 and the silicon optical chip 4052 form a resonant cavity, and the light beam with the specific wavelength is stably output by the semiconductor gain chip.

In some embodiments, the input coupler 40521 is designed as an inclined waveguide, that is, the optical waveguide of the input coupler 40521 is disposed at an angle with respect to the end surface of the silicon optical chip 4052, so that when a light beam emitted from the semiconductor gain chip enters the input coupler 40521 from the upper right side, part of the light beam may be reflected at the end surface of the silicon optical chip 4052, and the reflected light beam is emitted from the upper right side without returning to the semiconductor gain chip, thereby reducing the influence of the end surface light reflection of the silicon optical chip on the semiconductor gain chip.

Because one end face of the semiconductor gain chip adopts an inclined waveguide structure, the input coupler 40521 and the inclined waveguide structure of the semiconductor gain chip are arranged in parallel in the optical path direction, so that the semiconductor gain chip is matched with the silicon optical chip, the reflection of the optical field of the input coupler 40521 is reduced, and the quality of the optical beam is improved. Specifically, the input coupler 40521 and the inclined waveguide structure of the semiconductor gain chip may be arranged in parallel in the optical path direction, so that the exit angle of the light beam with a specific wavelength output by the input coupler 40521 is 20 °.

A directional coupler 40522, located between phase modulator 40523 and input coupler 40521, for splitting the beam. Specifically, a first end of the directional coupler 40522 is connected to the input coupler 40521 through an optical waveguide, a second end of the directional coupler 40522 is connected to the phase modulator 40523 through an optical waveguide, a third end of the directional coupler 40522 is connected to the fourth power monitor 40529 through an optical waveguide, and a fourth end of the directional coupler 40522 is connected to a first end of the wavelength sensor 405216 through an optical waveguide. The directional coupler 40522 splits the input light beam with a specific wavelength into three paths of light beams, the first path of light beam is transmitted to the input coupler 40521 through the first optical waveguide, and then is output to the outer side of the silicon optical chip 4052 through the input coupler 40521; the second light beam is transmitted to a fourth power monitor 40529 through an optical waveguide, so that the fourth power monitor 40529 monitors the optical power of the light beam with the specific wavelength; the third beam is transmitted to the wavelength sensor 405216 via an optical waveguide for wavelength locking.

And the phase modulator 40523, which is located between the directional coupler 40522 and the first power divider 40524, and is used for adjusting the wavelength of the light beam supported by the resonant cavity so as to match the light beam with the specific wavelength screened by the first filter 40526 and the second filter 40527 to coincide with the light beam in the resonant cavity. Specifically, a first end of the phase modulator 40523 is connected to a second end of the directional coupler 40522 through an optical waveguide, and a second end of the phase modulator 40523 is connected to the first power divider 40524 through an optical waveguide. The phase modulator 40523 is provided with a heater, and the cavity length of the phase modulator 40523 and further the cavity length of the resonant cavity are changed by changing the heater, so that a light beam with a certain wavelength supported by the resonant cavity coincides with a light beam with a specific wavelength screened by the two filters.

A first power splitter 40524 is positioned between the first filter 40526 and the phase modulator 40523 for splitting and combining the light beams. In particular, the method comprises the following steps of,

a first end of the first power divider 40524 is connected to a second end of the phase modulator 40523 by an optical waveguide, a second end of the first power divider 40524 is connected to the first filter 40526 by an optical waveguide, and a third end of the first power divider 40524 is connected to the second filter 40527 by an optical waveguide.

The power divider is generally referred to as a power divider. The power divider is a device which divides one path of input signal energy into two paths or outputs equal or unequal energy in multiple paths, and can also combine multiple paths of signal energy into one path of signal energy to output, and at this time, the power divider can also be called a combiner.

The first power divider 40524 may divide one of the light beams input by the phase modulator 40523 into two light beams, wherein one light beam passes through the first filter 40526 and then the second filter 40527, and the other light beam passes through the second filter 40527 and then the first filter 40526. The first power divider 40524 may further combine the light beam with a specific wavelength, which is first filtered by the first filter 40526 and then filtered by the second filter 40527, and the light beam with a specific wavelength, which is first filtered by the second filter 40527 and then filtered by the first filter 40526, into one light beam with a specific wavelength.

The splitting ratio of the first power divider 40524 is 50%:50 percent. Specifically, the first power divider 40524 divides one path of light beam by 50%:50% of the light beams are divided into two light beams, the two light beams are filtered by the first filter 40526 and the second filter 40527 and then return to the first power divider 40524, and according to the principle that the light path is reversible, other losses except the loss through the first filter 40526, the second filter 40527 and the optical waveguide are zero theoretically. The first power divider 40524 divides one path of light beam by 20%:80% of the light beams are divided into two light beams, the two light beams are filtered by the first filter 40526 and the second filter 40527 and then return to the first power divider 40524, and according to the principle that the light path is reversible, other losses except the loss of the first filter 40526, the second filter 40527 and the optical waveguide are larger than zero theoretically. Therefore, to minimize beam loss, in some embodiments, the splitting ratio of the first power splitter 40524 is 50%:50 percent.

A first filter 40526, in cooperation with the second filter 40527, screens a wavelength-specific light beam from a range of wavelengths emitted by the semiconductor gain chip 4051. Specifically, the first filter is coupled with the power divider through a first straight optical waveguide, the second filter is coupled with the first filter through a second straight optical waveguide, and the second filter is coupled with the first power divider through a third straight optical waveguide. The first filter 40526 and the second filter 40527 are both micro-ring structures, but have different circumferences, so that the wavelengths of the light beams screened by the first filter 40526 and the second filter 40527 are different. Based on the vernier effect, the light beam screened by the silicon photonic chip 4052 is a light beam of a specific wavelength only when the light beam screened by the first filter 40526 coincides with the wavelength of the light beam screened by the second filter 40527.

A 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 respectively coupled to the second straight optical waveguide, the second filter 40527 is coupled to the third straight optical waveguide, and a second end of the first power divider 40524 is connected to the third straight optical waveguide.

The first filter 40526 and the second filter 40527 screen the light beams of the specific wavelengths as follows:

a light beam of a wavelength band is incident through the input end of the first straight optical waveguide (close to the first power divider 40524), when the light beam is transmitted to the first coupling region of the first straight optical waveguide and the first filter 40526, a part of the light beam is coupled into the first filter 40526, and the remaining part of the light beam is output through the output end of the first straight optical waveguide (far from the first power divider 40524). When the light beam entering the first filter 40526 propagates through the second coupling region formed by the second straight optical waveguide and the first filter 40526, part of the light beam is coupled into the second straight optical waveguide, and the rest part of the light beam still propagates in the first filter 40526. When the light beam propagating in the first filter 40526 resonates to obtain enhanced coherence when the resonance condition m λ = nl of the first filter 40526 is satisfied, the optical power of the light beam obtained from the first filter 40526 by the second straight optical waveguide also increases, and the light beam which does not satisfy the resonance condition is output at the output end of the first straight optical waveguide. Where λ is the wavelength of the light beam, l is the perimeter of the first filter, n is the effective refractive index of the first filter, and m is a positive integer. I.e., the light beam satisfying the resonance condition of the first filter 40526, can be screened out by the first filter 40526 to be coupled into the second straight optical waveguide.

When the light beam is transmitted to the third coupling region of the second straight light waveguide and the second filter 40527, part of the light beam is coupled into the second filter 40527, and the remaining part of the light beam is output from the second output end of the second straight light waveguide. When the light beam propagating in the second filter 40527 passes through the fourth coupling region formed by the third straight light waveguide and the second filter 40527, part of the light beam is coupled into the third straight light waveguide, and the rest of the light beam still propagates in the second filter 40527. When the light beam propagating in the second filter 40527 satisfies the resonance condition m λ = nl of the second filter 405276, resonance occurs and thus coherence enhancement is obtained, and the optical power of the light beam obtained by the third straight optical waveguide from the second filter 40527 also increases, while light which does not satisfy the resonance condition is output at the second output end of the second straight optical waveguide. Where λ is the wavelength of the light beam, l is the perimeter of the second filter, n is the effective refractive index of the second filter, and m is a positive integer. I.e., the beam satisfying the resonance condition of the second filter 40527, can be screened out by the second filter 40527 for coupling into the third straight optical waveguide. At this time, the light beam received by the third straight light waveguide is a specific wavelength light beam.

The above is the process of the specific wavelength light beam screened by the first filter 40526 and then the second filter 40527. Similarly, the process of the specific wavelength light beam that is first filtered by the second filter 40527 and then filtered by the first filter 40526 is as follows:

light beams in a wavelength range are incident through an input end (close to the first power divider 40524) of the third straight optical waveguide, when the light beams are transmitted to a fourth coupling region of the third straight optical waveguide and the second filter 40527, a part of the light beams are coupled into the second filter 40527, and the rest of the light beams are output through an output end (far from the first power divider 40524) of the third straight optical waveguide. When the light beam propagating in the second filter 40527 passes through the third coupling region formed by the second straight light waveguide and the second filter 40527, part of the light beam is coupled into the second straight light waveguide, and the rest part of the light beam still propagates in the second filter 40527. When the light beam propagating in the second filter 40527 satisfies the resonance condition m λ = nl of the second filter 40527, resonance occurs and thus coherence enhancement is obtained, and the optical power of the light beam obtained from the second filter 40527 by the second straight optical waveguide is also increased, and light which does not satisfy the resonance condition is output at the output end of the third straight optical waveguide.

When the light beam is transmitted to the second coupling region of the second straight optical waveguide and the first filter 40526, a part of the light beam is coupled into the first filter 40526, and the remaining part of the light beam is output from the first output end of the second straight optical waveguide. When the optical beam entering the first filter 40526 propagates through the first coupling region formed by the first straight optical waveguide and the first filter 40526, a part of the optical beam is coupled into the first straight optical waveguide, and the remaining part of the optical beam still propagates in the first filter 40526. When the light beam propagating in the first filter 40526 satisfies the resonance condition m λ = nl of the first filter 40526, resonance occurs and thus coherence enhancement is obtained, the optical power of the light beam obtained from the first filter 40526 by the first straight optical waveguide also increases, and light that does not satisfy the resonance condition is output at the first output end of the second straight optical waveguide. At this time, the light beam received by the first straight light waveguide is a light beam of a specific wavelength.

The first filter 40526 and the second filter 40527 are both micro-ring structures, but have different circumferences, and the wavelengths of the light beams screened by the first filter 40526 and the second filter 40527 are different according to resonance conditions. Based on the vernier effect, the light beam screened by the silicon photonic chip 4052 is a light beam of a specific wavelength only when the light beam screened by the first filter 40526 coincides with the light beam screened by the second filter 40527.

First filter 40526, second filter 40527, and phase modulator 40523 comprise a wavelength tunable optical component. The wavelength tunable optical component is used for screening out a light beam with a specific wavelength from the light beams in a wavelength band emitted by the semiconductor gain chip 4051.

The first and

second filters

40526 and 40527 are capable of screening a wavelength-specific light beam from a range of wavelengths emitted by the semiconductor gain chip 4051, the wavelength value being determined by the characteristics of the first and

second filters

40526 and 40527. However, the resonant cavity formed by the semiconductor gain chip and the silicon optical chip can selectively support a plurality of light beams with different wavelengths according to the structure of the self cavity, and the light beams with the plurality of wavelengths supported by the resonant cavity are not necessarily coincident with the light beams screened by the two filters. If the light beams with a plurality of wavelengths supported by the resonant cavity do not coincide with the light beams with the specific wavelengths screened by the two filters, the cavity length of the phase modulator can be changed by changing the refractive index of the phase modulator, and further the cavity length of the resonant cavity is changed, so that the light beams with a certain wavelength supported by the resonant cavity coincide with the light beams with the specific wavelengths, and the resonant cavity emits the light beams with the specific wavelengths.

A fourth power monitor 40529 for monitoring the optical power of the wavelength specific optical beam to enable monitoring the optical power of the wavelength specific optical beam coupled by the semiconductor gain chip 4051. Specifically, the fourth power monitor 40529 is connected to the third end of the directional coupler 40522 via an optical waveguide. The fourth power monitor 40529 monitors the optical power of the second optical beam split by the directional coupler 40522, and further monitors the optical power of the first optical beam split by the directional coupler 40522 and input to the semiconductor gain chip 4051.

The value of the optical current flowing through the monitoring fourth power monitor 40529 in real time while the semiconductor gain chip 4051 is coupling the optical power of the specific wavelength optical beam. A fixed current is applied to the semiconductor gain chip 4051 and the relative positions of the semiconductor gain chip 4051 and the silicon optical chip 4052 are adjusted so that the value of the photocurrent flowing through the fourth power monitor 40529 varies with the coupling position. The position where the photocurrent is maximum is the position where the coupled optical power is maximum.

The wavelength sensor 405216 is further connected at a first end to the vertical coupler 405217 by an optical waveguide and at a second end to the fifth power monitor 405218 and the sixth power monitor 405219, respectively, by an optical waveguide, for measuring whether the specific wavelength beam changes, i.e., whether the specific wavelength beam deviates from the preset wavelength beam.

The wavelength sensor 405216 has a temperature insensitive characteristic. The filter curve of the wavelength sensor 405216 remains substantially unchanged as the temperature of the silicon photo chip changes. Therefore, the wavelength sensor 405216 can be used as a device for measuring whether or not a light beam of a specific wavelength is changed.

A fifth power monitor 405218 and a sixth power monitor 405219, respectively, for monitoring the optical power of the output beam at the output of the wavelength sensor 405216.

The wavelength sensor 405216, the fifth power monitor 405218 and the sixth power monitor 405219 constitute a wavelength-locked optical component to achieve wavelength locking. Specifically, the optical power monitored by the fifth power monitor 405218 is denoted as P _x The optical power monitored by the sixth power monitor 405219 is denoted as P _y According to P _x /P _y To characterize the direction of wavelength change of a particular wavelength beam. According to P _x /P _y Knowing the offset direction of the wavelength of the light beam with specific wavelength, P can be adjusted by adjusting the wavelength tunable optical component in the silicon optical chip 4052 _x /P _y And the preset value is restored. When P is present _x /P _y Restore to preWhen the value is set, the screened specific wavelength light beam is the preset wavelength light beam.

According to P _x /P _y To characterize the direction of wavelength change of a particular wavelength beam. Specifically, as can be known from the filtering curve diagram of the wavelength sensor 405216, the optical power (light intensity, which is equal to the optical power in a unit area, or intensity for short) of the light beam output by the output end of the wavelength sensor 405216 is in a cosine function relationship with the wavelength, that is, the optical powers monitored by the fifth power monitor 405218 and the sixth power monitor 405219 are both in a cosine function relationship, and both 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 are complementary to each other, and the wavelength sensor 405216 has a temperature insensitive characteristic, then the optical power can be measured according to P _x /P _y To characterize the direction of wavelength change of a particular wavelength beam.

For example, the wavelength of the preset wavelength light beam is set to 1549.7. When the wavelength of the input beam at the input of the wavelength sensor 405216 is 1549.7nm _x /P _y Equal to 1; when the wavelength of the input beam at the input end of the wavelength sensor 405216 is 1549.8nm _x / P _y Much greater than 1, indicating a deviation of 1549.8nm from the predetermined wavelength.

In some embodiments, also according to P _x /(P _x +P _y ) To characterize the direction of wavelength change of a particular wavelength beam; or, according to P _y /(P _x +P _y ) To characterize the direction of wavelength change of a particular wavelength beam.

According to P _x /P _y Knowing the offset direction of the wavelength of the light beam with specific wavelength, P can be adjusted by adjusting the wavelength tunable optical component in the silicon optical chip 4052 _x /P _y And the preset value is restored. Specifically, the first filter 40526 and the second filter 40527 are each provided with a heater. When P is _x /P _y When the light beam deviates from the preset value, the heaters of the first filter 40526 or the second filter 40527, or the first filter 40526 and the second filter 40527 are adjusted to change the refractive index of the filters, so that the wavelength of the light beam transmitted through the filters is changed, and the light beam screened out by the wavelength tunable optical component is a light beam with a specific wavelength.

A vertical coupler 405217 for coupling a light beam outside the silicon photo-chip 4052 into the silicon photo-chip 4052 to test the filtering characteristics of the wavelength sensor 405216. Specifically, the phase of the wavelength sensor 405216 is easily deviated due to material and process errors in the actual processing process of the silicon optical chip, and the filtering characteristics of the wavelength sensor 405216 are further changed. When the filter characteristic of the wavelength sensor 405216 is changed, it is considered that the specific wavelength light beam is not the preset wavelength light beam. To avoid this problem, it is necessary to test the filter characteristics of the wavelength sensor 405216 before the optical module is used. A predetermined wavelength beam outside the silicon photo-chip 4052 is coupled into the silicon photo-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 is present _x /P _y When deviating 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 filter characteristic of the wavelength sensor 405216.

As shown in figure 29, 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. In particular, the method comprises the following steps of,

the first optical splitter 4052161 is connected to the fourth end of the directional coupler 40522 and the vertical coupler 405217 through an optical waveguide at a first end, and connected to the first ends of the first modulating arm 4052163 and the second modulating arm 4052164 at a second end, so as to split the light beam transmitted by the directional coupler 40522 or the vertical coupler 405217 into two light beams, and transmit the two light beams to the first modulating arm 4052163 and the second modulating arm 4052164. In particular, the method comprises the following steps of,

the first end of the first splitter 4052161 includes a first input port and a second input port, the second end of the first splitter 4052161 includes a first output port and a second output port, the first input port is optically waveguided with the fourth end of the directional coupler 40522, the second input port is optically waveguided with the vertical coupler 405217, the first output port is connected with the first end of the first modulating arm 4052163, and the second output port is connected with the first end of the second modulating arm 4052164.

The first end of the second optical splitter 4052162 is connected to the second ends of the first and

second modulation arms

4052163 and 4052164, respectively, and the second end of the second optical splitter 4052162 is further connected to the fifth and sixth power monitors 405218 and 405219 through an optical waveguide, so as to couple the light beams on the first and

second modulation arms

4052163 and 4052164 into one light beam and further split the one light beam into two light beams. Wherein one of the light beams enters the fifth power monitor 405218 through the optical waveguide to be monitored by the fifth power monitor 405218; the other beam enters the sixth power monitor 405219 through the optical waveguide to be monitored by the sixth power monitor 405219. In particular, the method comprises the following steps of,

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 modulating arm 4052163, the fourth input port is connected to the second end of the second modulating arm 4052164, the third output port is connected to the fifth power monitor 405218 by an optical waveguide, and the fourth output port is connected to the sixth power monitor 405219 by an optical waveguide.

The first optical splitter 4052161 and the second optical splitter 4052162 both use the interference principle to realize light splitting and light combining.

The splitting ratios of the first and

second splitters

4052161 and 4052162 are equal. Specifically, when the splitting ratios of the first splitter 4052161 and the second splitter 4052162 are greatly different, the loss of the light beam is easily caused. To reduce beam loss, in some embodiments, the splitting ratios of the first and

second splitters

4052161, 4052162 are designed to be approximately equal. However, in order to further reduce the beam loss, the splitting ratios of the first and

second splitters

4052161 and 4052162 may be designed to be equal, and the splitting ratio of the first splitter 4052161 is 50%:50%, the splitting ratio of the second beam splitter 4052162 is also 50%:50 percent.

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 beam splitter 4052161. For example, at time T1, the light beam transmitted by the directional coupler 40522 is coupled to the first beam splitter 4052161; at time T2, the light beam transmitted by the vertical coupler 405217 is coupled to the first beam splitter 4052161.

A first modulating arm 4052163 has a first end connected to a second end of the first beam splitter 4052161 and a second end connected to a first end of the second beam splitter 4052162.

A second modulating arm 4052164, a first end connected to a second end of the first beam splitter 4052161 and a second end connected to a first end of the second beam splitter 4052162.

The first modulation arm 4052163 is a silicon waveguide, and the second modulation arm 4052164 is a silicon waveguide + a silicon nitride waveguide + a silicon waveguide.

The wavelength sensor 405216 has a temperature insensitive characteristic. In particular, the method comprises the following steps of,

the wavelength sensor based on the Mach-Zehnder interference principle has the advantages that the waveform of the output intensity of the output light beam of the wavelength sensor, changing along with the wavelength of the input light beam of the input end, of the output light beam of the output end is related to the refractive indexes of the upper modulation arm and the lower modulation arm and the length of the modulation arms, the difference value of the product of the refractive indexes of the two modulation arms and the length of the modulation arms in the two modulation arms determines the wavelength position of the input light beam, and therefore the waveform of the output intensity of the output light beam of the output end, changing along with the wavelength of the input light beam of the input end, of the output light beam of the output end at different temperatures can be guaranteed to be unchanged as long as the difference value of the product of the two modulation arms (the product of the refractive indexes and the length of the modulation arms) is not changed through the design of the waveguide, and the wavelength insensitivity of the input light beam along with the temperature is achieved.

Since the first modulation arm 4052164 is a silicon waveguide, and the second modulation arm 4052164 is a silicon waveguide, a silicon nitride waveguide and a silicon waveguide, only the lengths of the first modulation arm 4052164 and the second modulation arm 4052164 need to be adjusted, 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 is not changed, and the wavelength insensitivity with temperature can be realized.

Since the first end of the second modulation arm 4052164 is a silicon waveguide, the second end of the second modulation arm 4052164 is a silicon waveguide, and a silicon nitride waveguide is disposed between the first end and the second end of the second modulation arm 4052164, in order to enable a light beam with a specific wavelength to be smoothly transmitted between waveguides of two different materials, two waveguide converters are disposed on the second modulation arm 4052164, and are respectively disposed between the silicon waveguide and the silicon nitride waveguide.

Since the second modulation arm 4052164 is provided with two waveguide converters, 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.

As can be seen in fig. 29, in some embodiments, the first silicon photonics chip further includes a plurality of absorbers for absorbing optical power of the unwanted optical beam to avoid reflections and stray light generation. Specifically, the first silicon photochip includes a first absorber 405211, a second absorber 405212, a third absorber 405213 and a fourth absorber 405214.

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

The first absorber 405211 is used to absorb the other light beams passing through the first straight optical waveguide except the first filter 40526 and the second filter 40527. The second and

third absorbers

405212 and 405213 are used to absorb light beams in the second straight light waveguide that pass through the first and

second filters

40526 and 40527. The fourth absorber 405214 is used to absorb the light beams of the third straight light waveguide that pass through the first filter 40526 and the second filter 40527.

In some embodiments, the light source includes a semiconductor gain chip and a silicon photo chip. The silicon optical chip is used for receiving the light beams with a wavelength range emitted by the semiconductor gain chip, screening the light beams with the specific wavelength from the light beams and sending the light beams with the specific wavelength to the semiconductor gain chip. The semiconductor gain chip and the silicon optical chip form a resonant cavity, and the light beam with the specific wavelength is reflected back and forth between the semiconductor gain chip and the silicon optical chip, so that the resonant cavity emits the light beam with the specific wavelength. The silicon optical chip comprises an input coupler, a directional coupler, a wavelength tunable optical component, a wavelength sensor, a fifth power monitor and a sixth power monitor, wherein the directional coupler is respectively connected with the input coupler, the wavelength tunable optical component and the wavelength sensor through optical waveguides, and the wavelength sensor is also connected with the fifth power monitor and the sixth power monitor through optical waveguides. The input coupler, the directional coupler, the wavelength tunable optical component, the wavelength sensor, the fifth power monitor and the sixth power monitor are integrated on the silicon optical chip, so that the space is saved, the size of the light source is small, and the production requirement is met. The input coupler is used for receiving the light beam with one wavelength range emitted by the semiconductor gain chip and emitting the light beam with a specific wavelength to the semiconductor gain chip. Directional couplers are used to split a particular wavelength beam of light into beams. The wavelength tunable optical component is used for screening out light beams with specific wavelengths from light beams in a wavelength range so as to realize a wavelength tunable function. The wavelength sensor, the fifth power monitor and the sixth power monitor form a wavelength locking optical assembly, and the wavelength locking optical assembly represents whether a specific wavelength light beam deviates from a preset wavelength light beam according to the ratio of the optical power of the fifth power monitor to the optical power of the sixth power monitor so as to realize a wavelength locking function. When the specific wavelength light beam deviates from the preset wavelength light beam, the specific wavelength light beam does not deviate from the preset wavelength light beam by adjusting the wavelength tunable optical component. In the application, the input coupler, the directional coupler, the wavelength tunable optical component and the wavelength locking optical component are integrated on the silicon optical chip, so that the space is saved, the size of a light source is smaller, and the production requirement is met; the wavelength tunable optical component and the wavelength locking optical component are matched, so that the specific wavelength light beam output by the light source does not deviate from the preset wavelength light beam.

In order to solve the problem of the large size of the current light source, in some embodiments, another light source is also proposed. The light source comprises a semiconductor gain chip, a silicon optical chip, a wavelength calibration piece and a second power monitor, wherein the semiconductor gain chip is used for emitting a light beam with a wavelength range. The silicon optical chip is internally integrated with a wavelength tunable optical component which is used for screening out a light beam with a specific wavelength from light beams in a wavelength range emitted by the semiconductor gain chip so as to realize a wavelength tunable function. The semiconductor gain chip and the silicon optical chip form a resonant cavity, and the light beam with the specific wavelength is reflected back and forth between the semiconductor gain chip and the silicon optical chip, so that the light beam with the specific wavelength is stably output by the semiconductor gain chip. One power monitor, the wavelength calibration piece and the second power monitor in the silicon optical chip form a wavelength locking optical component. The wavelength locking optical assembly is used for judging whether the specific wavelength light beam deviates from the preset wavelength light beam or not so as to realize the wavelength locking function. If the specific wavelength light beam deviates from the preset wavelength light beam, the specific wavelength light beam screened by the wavelength tunable light component does not deviate from the preset wavelength light beam by adjusting the refractive index of the wavelength tunable light component. The semiconductor gain chip and the silicon optical chip form a resonant cavity, and the light beam with the specific wavelength is reflected back and forth between the semiconductor gain chip and the silicon optical chip, so that the light beam with the specific wavelength is stably output by the semiconductor gain chip. The silicon optical chip is internally integrated with a wavelength tunable optical component, and a power monitor, a wavelength calibration piece and a second power monitor in the silicon optical chip form a wavelength locking optical component, so that the light source can realize the functions of wavelength tuning and wavelength locking; space is also saved, so that the size of the light source is smaller to meet the production requirement.

As can be seen in fig. 17, 22 and 23, in some embodiments, the optical assembly 405 can include a fifth lens, a wavelength collimating component and a second power monitor in addition to the semiconductor gain chip 4051, the silicon optical chip 4052, the first lens 4053, the isolator 4054, the second lens 4055, the semiconductor amplification chip 4056, the third lens 4057, the beam splitter 4058, the first power monitor 4059 and the fourth lens 4060. In particular, the method comprises the following steps of,

the semiconductor gain chip 4051, the first lens 4053, the isolator 4054, the second lens 4055, the semiconductor amplification chip 4056, the third lens 4057, the beam splitter 4058, the first power monitor 4059, and the fourth lens 4060 have been described, and will not be described herein.

However, only the wavelength tunable optical component is disposed in the silicon optical chip 4052, and the wavelength locking optical component is not disposed therein. Therefore, the silicon optical chip 4052 can only realize wavelength tuning, and cannot realize wavelength locking.

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

And a fifth lens, which is respectively located on the same side of the silicon optical chip 4052 as the fourth lens 4060, is located between the silicon optical chip 4052 and the wavelength calibration member, and is used for coupling the light beam with the specific wavelength emitted by the silicon optical chip to the wavelength calibration member. Specifically, the fifth lens is a focusing lens, and the focusing lens focuses and couples the specific wavelength light beam to the wavelength calibration member.

The wavelength calibration piece is positioned between the fifth lens and the second power monitor.

The second power monitor is used for monitoring the optical power of the specific wavelength light beam flowing through the wavelength calibration member.

One power monitor, the wavelength calibration piece and a second power monitor in the silicon optical chip 4052 constitute a wavelength-locked optical component. The wavelength locking optical assembly is used for judging whether the specific wavelength light beam deviates from a preset wavelength light beam or not so as to realize the wavelength locking function.

FIG. 31 is an optical path diagram of a sixth optical assembly according to some embodiments. As can be seen in fig. 31, in some embodiments, the optical assembly 405 includes a semiconductor gain chip 4051, a silicon optical chip 4052, a first lens 4053, a fifth lens 4061, a wavelength collimating element 4062, and a second power monitor 4063.

The semiconductor gain chip 4051 is located between the silicon optical chip 4052 and the first lens 4053. The first lens 4053 is positioned between the semiconductor gain chip 4051 and the internal fiber adapter. A fifth lens 4061 is positioned between the silicon photonics chip 4052 and the wavelength collimating component 4062. The wavelength collimating component 4062 is positioned between the fifth lens 4061 and the second power monitor 4063.

The other components except the silicon optical chip 4052 in the light source are all placed on the same side of the silicon optical chip 4052, so that the space of the light source is effectively saved, the size of the light source is smaller, and the light source can meet the production requirement more easily.

Semiconductor gain chip 4051 is configured to emit a range of wavelengths of light. The silicon optical chip 4052 is used for receiving light beams in a wavelength range and screening light beams with specific wavelengths from the light beams in the wavelength range; and also for directing a wavelength specific beam into the semiconductor gain chip 4051 and the fifth lens 4061. The first lens 4053 is used to couple the wavelength-specific light beam emitted by the semiconductor gain chip 4051 into the internal fiber adapter. The fifth lens 4061 is used to couple the wavelength-specific light beam output by the silicon optical chip 4052 into the wavelength calibration piece 4062. The second power monitor 4063 is used to monitor the optical power of the wavelength-specific beam passing through the wavelength calibration piece 4062. The wavelength variation direction of the light beam with a specific wavelength is characterized according to the ratio (P1/P0) of the optical power (denoted as P0) monitored by one power monitor in the silicon optical chips 4052 for monitoring the light beam with a specific wavelength to the optical power (denoted as P1) monitored by the second power monitor 4063.

The semiconductor gain chip 4051 emits a light beam of a wavelength range incident on the silicon optical chip 4052, the silicon optical chip 4052 selects a light beam of a specific wavelength from the light beam of the wavelength range, the light beam of the specific wavelength is incident on the fifth lens 4061, the fifth lens 4061 couples the light beam of the specific wavelength output from the silicon optical chip 4052 to the wavelength calibration member 4062, and the second power monitor 4063 monitors the optical power of the light beam of the specific wavelength passing through the wavelength calibration member 4062.

One of the power monitors in the silicon optical chip 4052 forms a wavelength-locked optical component with the wavelength calibration piece 4061 and the second power monitor 4063. The wavelength-locked optical component characterizes whether the specific wavelength beam deviates from a preset wavelength beam according to a ratio of the optical power of the second power monitor 4063 to the optical power of one of the silicon optical chips 4052, so as to achieve wavelength locking.

When the wavelength of the screened specific wavelength light beam deviates from the wavelength of the preset wavelength light beam, the optical power of the second power monitor 4063 changes, so that P1/P0 deviates from the preset value. When the wavelength of the screened light beam with the specific wavelength deviates from the wavelength of the preset light beam, the optical power inputted into the second power monitor 4063 from the wavelength calibration piece changes, so that P1/P0 deviates from the preset value. The increase or decrease of P1/P0 reflects the direction of the shift of the wavelength of the light beam with a specific wavelength, i.e., whether the wavelength of the light beam with a specific wavelength is shifted toward a long wavelength or a short wavelength. When the direction of the offset is known, P1/P0 can be restored to the preset value by adjusting the components in the silicon optical chip 4052. When the P1/P0 is recovered to the preset value, the wavelength of the screened specific wavelength light beam is the wavelength of the preset wavelength light beam. The preset wavelength light beam is a local oscillation light beam satisfying the coherent component.

The light beam of the specific wavelength is incident not only into the fifth lens 4061 but also into the semiconductor gain chip 4051. The light beam with the specific wavelength is also incident on the semiconductor gain chip 4051, and then reflected to the silicon optical chip 4052 through the semiconductor gain chip 4051, that is, the light beam with the specific wavelength is reflected back and forth between the silicon optical chip 4052 and the semiconductor gain chip 4051. The semiconductor gain chip 4051 and the silicon optical chip 4052 form a resonant cavity, and the light beam with the specific wavelength is reflected back and forth between the silicon optical chip 4052 and the semiconductor gain chip 4051, so that the light beam with the specific wavelength is stably output by the semiconductor gain chip. The first lens 4053 is used to couple the wavelength-specific light beam emitted by the semiconductor gain chip 4051 into the internal fiber adapter.

As can be seen in conjunction with fig. 24, 25 and 31, the optical assembly 405 further includes an isolator 4054 and a second lens 4055.

As can be seen in fig. 24, 26 and 31, the optical assembly 405 further includes a semiconductor magnifying chip 4056 and a third lens 4057.

As can be seen in conjunction with fig. 24, 27, and 31, the optical assembly 405 also includes a beam splitter 4058 and a first power monitor 4059.

As can be seen in conjunction with fig. 24, 28 and 31, the optical assembly 405 also includes a fourth lens 4060.

FIG. 32 is a block diagram of a second type of silicon photonics chip in accordance with some embodiments. As can be seen in fig. 31-32, in some embodiments, silicon optical 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 processing a silicon optical chip by using a CMOS process. In particular, the method comprises the following steps of,

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

Input coupler 40521, phase modulator 40523, first power divider 40524, first filter 40526, second filter 40527, and fourth power monitor 40529 have been described and will not be described herein.

A first end of the directional coupler 40522 is connected to the input coupler 40521 through an optical waveguide, a second end of the directional coupler 40522 is connected to the phase modulator 40523 through an optical waveguide, a third end of the directional coupler 40522 is connected to the fourth power monitor 40529 through an optical waveguide, and a fourth end of the directional coupler 40522 is connected to the second power splitter 40525 through an optical waveguide. The directional coupler 40522 splits the input specific wavelength light beam into three paths of light beams, the first path of light beam is transmitted to the input coupler 40521 through the first optical waveguide and then is output to the outer side of the silicon optical chip 4052 through the input coupler 40521; the second light beam is transmitted to a fourth power monitor 40529 through an optical waveguide, so that the fourth power monitor 40529 monitors the optical power of the light beam with the specific wavelength; the third beam is transmitted to the second power divider 40525 via the optical waveguide for wavelength locking.

A second power splitter 40525, located between the directional coupler 40522 and the third power monitor 40528, and also located between the directional coupler 40522 and the output coupler 405210, for splitting light. Specifically, a first end of the second power divider 40525 is connected to the fourth end of the directional coupler 40522 through an optical waveguide, a second end of the second power divider 40525 is connected to the third power monitor 40528 through an optical waveguide, and a third end of the second power divider 40525 is connected to the output coupler 405210 through an optical waveguide. The second power divider 40525 divides the third light beam divided by the directional coupler 40522 into two light beams, and one light beam is transmitted to the third power monitor 40528 through the optical waveguide, so that the third power monitor 40528 monitors the optical power of the light beam with a specific wavelength; the other beam is transmitted to the output coupler 405210 through the optical waveguide.

The splitting ratio of the second power divider 40525 may be any ratio. When the splitting ratio of the second power divider 40525 changes, the preset value of P1/P0 also changes. The preset value of P1/P0 can be changed correspondingly only when the splitting ratio of the second power divider 40525 changes.

A third power monitor 40528 for monitoring the optical power of the wavelength-specific optical beam in real time. Specifically, the third power monitor 40528 is connected to the second end of the second power divider 40525 via an optical waveguide. A third power monitor 40528 monitors the optical power of one of the beams split by the second power splitter 40525.

Among these, the power monitor for monitoring the light beam with a specific wavelength in the silicon optical chip 4052 is the third power monitor 40528.

An output coupler 405210, provided at one side end face of the silicon photo chip 4052, for coupling the light beam of the specific wavelength into the fifth lens 4061. Specifically, the output coupler 405210 and the second power divider 40525 are connected by an optical waveguide. The output coupler 405210 couples the other beam split by the second power splitter 40525 into the fifth lens 4061.

In some embodiments, the output coupler 405210 is designed with a slanted waveguide, i.e., the waveguide of the output coupler 405210 is disposed at an angle to the end face of the silicon photonic chip 40521, such that the signal light output by the output coupler 405210 exits the end face of the silicon photonic chip horizontally for coupling with the second lens 4055 outside the silicon photonic chip 4052.

The third power monitor 40528 implements wavelength locking with the wavelength calibration piece 4062 and the second power monitor 4063 outside the silicon optical chip 4052. Specifically, the optical power monitored by the third power monitor 40528 is denoted as P0, the optical power monitored by the second power monitor 4063 is denoted as P1, and the wavelength calibration component 4062 represents the wavelength variation direction of the light beam with a specific wavelength according to P1/P0. The wavelength calibration part knows the shift direction of the wavelength of the light beam with the specific wavelength according to the P1/P0, and the P1/P0 is restored to the preset value by adjusting the devices in the silicon optical chip 4052. When the P1/P0 is recovered to the preset value, the screened specific wavelength light beam is the preset wavelength light beam.

As can be seen in fig. 32, in some embodiments, the second silicon microchip further comprises a plurality of absorbers for absorbing the optical power of the unwanted optical beam to avoid reflection and stray light generation. Specifically, the first silicon photochip 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 and will not be described herein.

FIG. 33 is a block diagram of a third type of silicon photonics chip in accordance with some embodiments. As can be seen in fig. 33, in some embodiments, the third type of silicon optical 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 processing a silicon optical chip by using a CMOS process. In particular, the method comprises the following steps of,

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 described and will not be described herein.

A first end of the directional coupler 40522 is connected to the input coupler 40521 through an optical waveguide, a second end of the directional coupler 40522 is connected to the phase modulator 40523 through an optical waveguide, and a third end of the directional coupler 40522 is connected to the second power splitter 40525 through an optical waveguide. The directional coupler 40522 splits the input specific wavelength light beam into multiple paths of light beams, the first path of light beam is transmitted to the input coupler 40521 through the first optical waveguide and then is output to the outer side of the silicon optical chip 4052 through the input coupler 40521; the second beam is transmitted to the second power divider 40525 via the optical waveguide for wavelength locking.

A second power splitter 40525, located between the directional coupler 40522 and the third power monitor 40528, and also located between the directional coupler 40522 and the output coupler 405210, for splitting light. Specifically, a first end of the second power divider 40525 is connected to a third end of the directional coupler 40522 through an optical waveguide, a second end of the second power divider 40525 is connected to the third power monitor 40528 through an optical waveguide, and the third end of the second power divider 40525 is connected to the output coupler 405210 through an optical waveguide. The second power divider 40525 divides the second light beam divided by the directional coupler 40522 into two light beams, and one light beam is transmitted to the third power monitor 40528 through the optical waveguide, so that the third power monitor 40528 monitors the optical power of the light beam with a specific wavelength; the other beam is transmitted to the output coupler 405210 via the optical waveguide.

A third power monitor 40528 for monitoring the optical power of the wavelength specific beam. Specifically, the third power monitor 40528 is connected to the second end of the second power divider 40525 via an optical waveguide. The third power monitor 40528 monitors the optical power of the second beam split by the directional coupler 40522, and then monitors the optical power of the first beam split by the directional coupler 40522 and input to the semiconductor gain chip 4051.

Among them, the power monitor for monitoring the light beam with a specific wavelength in the silicon optical chip 4052 is the third power monitor 40528.

The third power monitor 40528 implements wavelength locking with the wavelength calibration piece 4062 and the second power monitor 4063 outside the silicon optical chip 4052. Specifically, the optical power monitored by the third power monitor 40528 is denoted as P0, the optical power monitored by the second power monitor 4063 is denoted as P1, and the wavelength change direction of the light beam with a specific wavelength is characterized according to P1/P0. The offset direction of the wavelength of the light beam with the specific wavelength is known according to the P1/P0, and the P1/P0 is restored to the preset value by adjusting the devices in the silicon optical chip 4052. When the P1/P0 is recovered to the preset value, the screened specific wavelength light beam is the preset wavelength light beam.

As can be seen in fig. 33, in some embodiments, the third silicon photonic chip further includes a plurality of absorbers for absorbing the optical power of the unwanted optical beam to avoid reflection and stray light. Specifically, the third silicon microchip includes a first absorber 405211, a second absorber 405212, a third absorber 405213, a fourth absorber 405214, and a fifth absorber 405215.

The first absorber 405211, the second absorber 405212, the third absorber 405213, the fourth absorber 405214 and the fifth absorber 405215 have been described and will not be described herein.

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

In some embodiments, the second and third types of silicon photonics chips further include a plurality of thermal isolation slots 405216. The thermal isolation trench 405216 is formed by etching the surface of the silicon optical chip 4052. The thermal insulation groove 405216 is placed between each device in the silicon optical chip 4052, thereby reducing the thermal crosstalk between each device in the silicon optical chip 4052 and improving the performance of the silicon optical chip 4052.

For the second silicon optical chip, the thermal insulation slot 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.

An insulating slot 405216 is placed between directional coupler 40522 and phase modulator 40523 where insulating slot 405216 reduces thermal crosstalk between directional coupler 40522 and phase modulator 40523. The thermal isolation slot 405216 is positioned between the first power divider 40524 and the first filter 40526 where the thermal isolation slot 405216 reduces thermal crosstalk between the first power divider 40524 and the first filter 40526. The thermal shield 405216 is placed between the first filter 40526 and the second filter 40527 where the thermal shield 405216 reduces thermal crosstalk between the first filter 40526 and the second filter 40527. The thermally insulating slots 405216 are placed between the second filter 40527 and the third power monitor 40528, where the thermally insulating slots 405216 reduce thermal crosstalk between the second filter 40527 and the third power monitor 40528. A thermal shield 405216 is placed between phase modulator 40523 and second power divider 40525, where thermal shield 405216 reduces thermal crosstalk between phase modulator 40523 and second power divider 40525. An insulating slot 405216 is placed between the directional coupler 40522 and the second power divider 40525, where the insulating slot 405216 reduces thermal crosstalk between the directional coupler 40522 and the second power divider 40525.

The first silicon optical chip, the second silicon optical chip and the third silicon optical chip are all silicon optical chips integrated with wavelength tunable optical components by using a Complementary Metal Oxide Semiconductor (CMOS) process, the first silicon optical chip is also integrated with a wavelength locking optical component, and a power monitor integrated in the second silicon optical chip and the third silicon optical chip, a wavelength calibration piece outside the silicon optical chip and the second power monitor form the wavelength locking optical component.

In some embodiments, the light source includes a semiconductor gain chip, a silicon optical chip, a wavelength calibration piece, and a second power monitor. The silicon optical chip is used for receiving the light beams with a wavelength range emitted by the semiconductor gain chip, screening the light beams with specific wavelengths, and sending the light beams with specific wavelengths to the semiconductor gain chip and the wavelength calibration piece. The semiconductor gain chip and the silicon optical chip form a resonant cavity, and the light beam with the specific wavelength is reflected back and forth between the semiconductor gain chip and the silicon optical chip, so that the resonant cavity emits the light beam with the specific wavelength. The second power monitor is used for monitoring the optical power of the specific wavelength light beam flowing through the wavelength calibration member. The silicon optical chip comprises an input coupler, a directional coupler, a wavelength tunable optical component, a second power divider, a third power monitor and an output coupler, wherein the directional coupler is respectively connected with the input coupler, the wavelength tunable optical component and the second power divider through optical waveguides, the third power monitor and the output coupler are respectively connected with the second power divider through optical waveguides, and the input coupler and the output coupler are positioned on the same side of the silicon optical chip. The input coupler, the directional coupler, the wavelength tunable optical component, the second power divider, the third power monitor and the output coupler are integrated on the silicon optical chip, so that the space is saved, the size of the light source is smaller, and the production requirement is met. The input coupler is used for receiving the light beam with one wavelength range emitted by the semiconductor gain chip and emitting the light beam with a specific wavelength to the semiconductor gain chip. Directional couplers are used to split a particular wavelength beam of light into beams. The wavelength tunable optical component is used for screening a light beam with a specific wavelength from light beams in a wavelength range so as to realize a wavelength tunable function. The second power divider is used for dividing the light beam which is divided by the directional coupler and then flows through the directional coupler into light beams. A third power monitor is used to monitor the optical power of one of the beams. The output coupler is used for emitting the other light beam to the wavelength calibration piece. The third power monitor, the wavelength calibration piece and the second power monitor form a wavelength locking optical assembly, and the wavelength locking optical assembly represents whether the specific wavelength light beam deviates from the preset wavelength light beam according to the ratio of the optical power of the second power monitor to the optical power of the third power monitor so as to realize the wavelength locking function. When the specific wavelength light beam deviates from the preset wavelength light beam, the wavelength tunable optical component is adjusted to enable the specific wavelength light beam not to deviate from the preset wavelength light beam. In the application, the input coupler, the directional coupler, the wavelength tunable optical component, the second power divider, the third power monitor and the output coupler are integrated on the silicon optical chip, so that the space is saved, the size of a light source is smaller, and the production requirement is met; the wavelength tunable optical component and the wavelength locking optical component are matched, so that the specific wavelength light beam output by the light source does not deviate from the preset wavelength light beam.

Under the push of large-scale and super-large-scale cloud data center providers, the transmission rate of optical modules is rapidly increased, such as 200G/400G high-speed optical modules.

The optical module provided by the embodiment of the application is a coherent optical module, and further is a silicon optical coherent optical module; the coherent optical module is an optical module with a transmitting end adopting coherent modulation and a receiving end adopting coherent technology for detection.

At the transmitting end, besides amplitude modulation of light, frequency or phase modulation can be performed in an external modulation mode, such as QAM; further, an external modulation mode is adopted at a transmitting end, an IQ modulator based on a Mach-Zehnder modulator (MZM) is used for realizing high-order modulation, and a signal is modulated onto an optical carrier, so that light carrying the signal is generated and transmitted. Specifically, the silicon optical chip is internally provided with a Mach-Zehnder modulator to realize power and phase modulation. The Mach-Zehnder modulator modulation adopts the same-wavelength light interference principle, one Mach-Zehnder modulator is provided with two interference arms, one beam of light is input to one single interference arm, two beams of light with the same wavelength need to be provided for one Mach-Zehnder modulator in total, and after the light is modulated by the Mach-Zehnder modulator, the light on the interference arms can be combined into one beam of light. The single-wavelength light can be provided for the silicon optical chip, and the light splitting waveguide in the silicon optical chip divides the single-wavelength light into two beams of light with the same wavelength which are respectively input to two interference arms of the Mach-Zehnder modulator; two beams of light with the same wavelength can be provided for the silicon optical chip, and the two beams of light with the same wavelength are directly and respectively input to the two interference arms of the Mach-Zehnder modulator; because the Mach-Zehnder modulator finally fuses the light on each interference arm, the scheme of providing two beams of light for the silicon optical chip can provide higher optical power than the scheme of providing one beam of light on the premise of adopting a single same optical power chip.

At a receiving end, mixing frequency in an optical mixer by using local oscillator light and a received external optical signal to obtain a difference frequency signal changing with the frequency, the phase and the amplitude of the external optical signal according to the same rule; the size of the output photocurrent after coherent mixing is in direct proportion to the product of the external optical signal power and the local oscillator optical signal power, and the output photocurrent after coherent mixing is greatly increased because the local oscillator optical power is greater than the external optical signal power, and the detection sensitivity is further improved. Therefore, in the incoherent optical module, a plurality of amplifiers are used for continuously relaying and amplifying signals in the transmission process, and in the coherent optical module, weak arrival signals are directly subjected to mixing amplification at the receiving end.

Further, the optical signal will be distorted during the transmission process of the optical fiber link; in the embodiment of the application, a Digital Signal Processing (DSP) technology is adopted, so that distortion is resisted and compensated, and the influence of the distortion on the error rate of a system is reduced; DSP techniques can perform various signal compensation processes such as chromatic dispersion compensation and polarization mode dispersion compensation.

Fig. 34 is a schematic view of a coherent assembly according to an embodiment of the present application, and fig. 35 is an exploded schematic view of a coherent assembly according to an embodiment of the present application, as shown in fig. 34 and fig. 35, the coherent assembly 500 generally includes a cover shell 501 and a carrier plate 502, the cover shell 501 is snap-fitted on the carrier plate 502 to form a coherent housing having an opening; the outer contour of the housing generally appears square.

A first U-shaped groove 5021 is disposed at the opening on the side of the carrier plate 502. One side of the cover case 501 is provided with a mounting groove 5013, the position of which 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 mounting of the carrier plate 502 and the shell. The first limiting part and the second limiting part are respectively arranged on two sides of the mounting groove. In order to realize the installation and the limitation of the carrier plate 502 and the cover shell 501, the lower surfaces of the first limiting part and the second limiting part are lower than the upper surface of the carrier plate 502, and when the carrier plate is installed, the first limiting part and the second limiting part are abutted against the side wall of the carrier plate 502 to realize the limitation in the length direction. The first U-shaped groove 5021 is also called a support plate groove.

The opening of coherent shell sets up towards the wavelength adjustable optical component, and the opening part sets up optical fiber splice, and optical fiber splice department sets up fiber array, and including local oscillator optical fiber, receiving fiber and transmitting fiber. One end of the optical fiber connector extends into the opening. One end of the local oscillator optical fiber is connected with the wavelength tunable optical component to receive the local oscillator light. The receiving optical fiber is connected with the receiving adapter and used for receiving the receiving signal light which is sent to the inside of the optical module from the outside. And the transmitting optical fiber is connected with the transmitting adapter and used for transmitting the modulated transmitting signal light.

The optical fiber fixing member 503 is fixedly connected to the optical fiber connector and the cover shell, and is used for fixing the optical fiber connector to the cover shell.

Fig. 36 is a schematic diagram of a carrier board structure according to an example of the present application, and as shown in the figure, a coherent optical chip 510 is carried above the carrier board 502 for modulating and demodulating an optical signal. The side surface of the coherent optical chip 510 is provided with an optical port, and the end surface of the optical port is coupled with the end surface of the optical fiber connector. The first electrical chip 520 is disposed on the surface of the carrier 502, disposed on the side surface of the coherent optical chip, and electrically connected to the coherent optical chip. The second electrical chip 530 is disposed on the surface of the carrier 502, disposed on the side of the coherent optical chip, and electrically connected to the coherent optical chip. The third electrical chip 540 is disposed on the surface of the carrier 502, disposed on the side of the coherent optical chip, and electrically connected to the coherent optical chip.

In the present example, the first electrical chip 520 is a coherent emission driving chip, and is located at the opposite side of the optical port of the coherent optical chip, for driving the coherent modulator in the coherent optical chip. The second electrical chip 530 and the third electrical chip 540 are receiving amplification chips, located on the side near the coherent emission driving chip, and disposed near the coherent optical chip, for amplifying the received electrical signals.

The carrier plate 502 further carries a plurality of power supply circuits for supplying power to the balanced receiver, the power monitor, and the transmitting optical attenuator inside the coherent optical chip, and the specific settings of the electrical devices are set according to the settings of the functional pins of the coherent optical chip. The carrier 502 is a high-speed carrier 502, and is electrically connected to the circuit board by providing a conductive region on a side or a lower surface thereof.

Since the optoelectronic chips on the surface of the carrier plate 502 have a certain height and weight and are distributed relatively intensively, the center of gravity of the carrier plate 502 is not near the geometric center of gravity thereof, but is close to the position of the coherent optical chip. To increase the structural stability of the coherent assembly 500 such that its geometric center coincides as much as possible with the center of gravity, the center of gravity of the cover housing 501 is arranged to be symmetrical to the center of gravity of the carrier plate 502.

Fig. 37 is a first structural diagram of a cover case of the present application, and fig. 38 is a second structural diagram of a cover case of the present application. Fig. 37 and 38 are schematic structural views of the cover case 501 at different angles, the cover case 501 has a rectangular structure, and a mounting groove 5013 is formed in one side of the cover case 501, and the position of the mounting groove 5013 corresponds to the position of the first U-shaped groove. The cover housing 501 is provided with a first limit portion 5011 and a second limit portion 5012 for limiting the mounting of the carrier plate 502 and the housing. The first and second limiting

portions

5011 and 5012 are disposed at both sides of the mounting groove 5013, respectively. In order to realize the mounting and limiting of the carrier 502 and the cover shell 501, the lower surfaces of the first limiting portion 5011 and the second limiting portion 5012 are disposed lower than the upper surface of the carrier 502, and when the carrier is mounted, the first limiting portion 5011 and the second limiting portion 5012 are abutted against the sidewall of the carrier 502 to realize the limiting in the length direction. The cover shell 501 is provided with coherent mounting protrusions protruding from the upper surface of the cover shell 501, and the coherent mounting protrusions are arranged along the shape of the mounting groove and used for connection limitation between the cover shell 501 and the extension part.

In order to achieve the smooth surface of the coherent assembly 500 and facilitate the installation of the coherent assembly 500 inside the optical module, a bearing plate 50111 is disposed around the installation groove, and the upper surface of the bearing plate is connected to the lower surface of the extension portion to limit the vertical position of the optical fiber fixing member on the cover shell 501. In the present example, the upper surface of the extension is disposed flush with the upper surface of the coherent mounting bump 5016.

The protruding lateral wall of coherent installation leans on with the lateral wall of extension portion to be connected, realizes the spacing of extension portion in the horizontal direction, has further realized that the coupling of fiber array and coherent light chip is spacing.

For the extension portion and the relevant bellied spacing of installation of making things convenient for the optic fibre mounting, loading board 50111 is provided with the spacing portion of installation, include: the first mounting limiting portion 5014 and the second mounting limiting portion 5015, which protrude from the upper surface of the carrier plate, are flush with the upper surface of the coherent mounting protrusion 5016 for the integrity of the surface of the coherent component.

In the present example, the first mounting limiting portion 5014 and the second mounting limiting portion 5015 may be symmetrically or asymmetrically disposed. For convenient installation and use, the first installation limiting part 5014 and the second installation limiting part 5015 are symmetrically arranged. The first and second

mounting limiting portions

5014 and 5015 may be semi-circular in configuration, or may be triangular or other geometric configuration.

The lower surface of the cover shell 501 is provided with support arms, which are located around the lower surface of the cover shell 501 and used for connecting with a carrier plate.

The lower surface of the cover 501 is provided with cover protrusions having different heights to adapt to the structure of the optoelectronic device on the carrier 502. The cover case 501 is provided with a connecting portion, which is connected to the upper surface of the carrier plate 502 and protrudes from the lower surface of the cover case 501. The lower surface of the cover housing 501 is provided with first 5018 and second 5017 bump platforms having different heights, wherein the first 5018 bump out of the lower surface of the cover housing 501 and are arranged corresponding to the positions of the first, second and third electrical chips. The lower surface of the first raised platform 5018 is disposed higher than the lower surface of the second raised platform and the lower surface of the second raised platform 5017 is disposed higher than the connection portion. The first raised platform 5018 comprises a first sub-platform 50181 and a second sub-platform 50182, the first sub-platform 50181 being arranged above the first electrical chip 520, which in projection onto the carrier 502 covers the first electrical chip 520; the second sub-platform 50182 is disposed above the second electrical chip 530 and the third electrical chip 540, and its projection on the carrier 502 covers the second electrical chip 530 and the third electrical chip 540. The bottom surface of the cover case 501 covers the coherent optical chip.

The second raised platform 5017 covers other electrical devices on the carrier 502, and the second raised platform 5017 is disposed at the edge of the first raised platform 5018 and located between the first raised platform 5018 and the connecting portion. The second bump 5017 is further provided with a bump connector 5019 located at the corner farthest from the coherent optical chip, and connected to the carrier 502 through an electrically conductive silver paste, so that heat on the carrier 502 can be dissipated through the bump connector and the cover 501.

In the present example, the first and

second bump platforms

5018 and 5017 are disposed at diagonal positions of the coherent light chip, and since the thicknesses of the first and

second bump platforms

5018 and 5017 are higher than the thickness of the bottom surface of the cover case 501, the center of gravity of the cover case 501 is located at a position close to the second bump platform 5017. After the cover shell 501 and the carrier plate 502 are covered, the center of gravity of the coherent assembly 500 is close to the geometric center as much as possible, and the stability of the coherent assembly 500 is ensured.

Fig. 39 is a schematic diagram illustrating an optical fiber connector and a coherent component according to an example of the present application, and as shown in fig. 39, a coherent connection board 550 is connected across the coherent optical chip 510 and the optical fiber connector 504 for fixing the coherent optical chip and the optical fiber connector. And the optical fiber adapter is correspondingly connected with the optical fiber in the optical fiber joint.

In order to avoid the light in the optical fiber connector from forming reflection at the joint of the end face of the optical fiber connector and the end face of the coherent light chip and influencing the optical power, the central axis of the optical fiber array and the central axis of the optical port of the coherent light chip form an included angle of 6-8 degrees, and the reflection formed by the light at the joint of the end face of the optical fiber connector and the end face of the coherent light chip is reduced.

In the present example, the optical fiber connector 504 is a rectangular parallelepiped, and a coherent connection board 550 is disposed above the rectangular parallelepiped and spans between the coherent optical chip and the optical fiber connector. The lower surface of the coherent connection board 550 is provided with a glue for connecting and fixing the coherent connection board 550 and the optical fiber connector and the coherent connection board 550 and the coherent optical chip.

In order to reduce the phenomenon that the coupling precision of the optical fiber connector and the coherent optical chip is deteriorated due to the fact that the optical fiber is pulled by external force in the transportation or use process, a tail fiber sleeve 5041 is further arranged in the application and is sleeved with the outside of the optical fiber array. The optical fiber fixing piece is arranged outside the optical fiber connector and fixedly connected with the tail optical fiber sleeve. The upper surface of the tail fiber sleeve 5041 is provided with double-sided adhesive material or glue material which is connected with the optical fiber fixing piece. In the example of the application, the pigtail sleeve is a square tube with a through hole, the optical fiber array is penetrated through one end of the square tube, the optical fiber connector abuts against the end of the square tube, and glue is filled between the optical fiber array and the pigtail sleeve for connection.

FIG. 40 is a first schematic structural view of an exemplary fiber mount of the present application. FIG. 41 is a second schematic structural view of an optical fiber securing member. As shown in fig. 39 and 40, the optical fiber fixing member has the same thickness and is made of a plate material by die casting, and includes: a fixed bottom plate 5031, and a first fiber side plate 5032 and a second fiber side plate 5033 disposed at both sides of the fixed bottom plate, wherein the fixed bottom plate 5031 includes a first fixed bottom plate 50311 and a second fixed bottom plate 50312 having different heights, and an upper surface of the second fixed bottom plate 50312 is disposed higher than an upper surface of the first fixed bottom plate. The tail fiber sleeve 5041 is arranged in a space formed by the first fixed bottom plate, the first optical fiber side plate and the second optical fiber side plate in an enclosing mode. The coherent connection board 550 is disposed on the upper surface of the coherent optical chip and the optical fiber connector, so that the upper surface of the coherent connection board 550 is higher than the upper surface of the optical fiber connector, and the upper surface of the coherent connection board 550 is connected to the second fixing base 50312. The first and second fixed bottom plates 50312 of different heights are configured to accommodate the height of the coherent connection plate 550.

The upper surface of the tail fiber sleeve is connected with the lower surface of the first fixing bottom plate, and the side surface of the tail fiber sleeve is connected with the first optical fiber side plate and the second optical fiber side plate.

An extension 50313 with a width greater than that of the second fixing bottom plate 50312 is disposed on one side of the second fixing bottom plate 50312. The side of the extending portion 50313 is provided with a first extending limiting groove 503131 and a second extending limiting groove 503132 for limiting with the corresponding structure on the upper surface of the cover shell 501, so as to facilitate the connection and fixation between the optical fiber fixing member and the cover shell 501. In order to facilitate the connection and fixation between the optical fiber fixing member and the cover shell 501, a plurality of dispensing grooves 5034 are further disposed at the side of the extending portion 50313, and after the extending portion 50313 and the cover shell 501 are positioned, liquid glue is dispensed at the dispensing grooves to realize the connection between the extending portion 50313 and the cover shell 501.

In the example of the application, the shape of the dispensing groove is the same as that of the first extending limiting groove and that of the second extending limiting groove.

The first elongated groove 503131 is in mating connection with the first mounting stop portion 5014, and the second elongated groove 503132 is in mating connection with the second mounting stop portion 5015.

In the installation process of the present application example, first, the coherent optical chip is installed and connected to the carrier plate 502, the pigtail sleeve 5041 is connected to the optical fiber array, the optical port of the coherent optical chip protrudes out of the first U-shaped groove of the carrier plate 502, and then the coherent connection board 550 is bridged over the optical fiber connector and the coherent optical chip to realize the coupling connection between the optical fiber connector and the coherent optical chip. Then, the cover shell 501 is connected with the edge of the carrier plate 502, the first limiting portion and the second limiting portion abut against the side edge of the carrier plate 502 in the installation process, the connecting portion of the cover shell 501 is connected with the carrier plate 502, and the protruding connecting portion is connected with the edge of the carrier plate 502. The first bottom fixing plate of the fiber fixing member is connected to the pigtail sleeve 5041, the second bottom fixing plate 50312 is connected to the coherent connection plate 550, and the extension 50313 is connected to the carrier plate 502 on the upper surface of the cover housing 501. Through the connection, the optical fiber connector is fixedly connected with the optical fiber fixing piece through the tail optical fiber sleeve 5041 and the coherent connecting plate 550, when the optical fiber receives external acting force, the force received by the connecting part is dispersed and transferred, the stress of the optical fiber connector is reduced, the connection stability of the optical fiber connector and a coherent optical chip is improved, and the optical coupling precision is avoided.

In the application example, the optical fiber array and the coherent light chip are connected through the glass bridge, and the flexible glue connection is used, so that the maintainability is strong, and the production and the manufacture are facilitated. The upper shell is divided into two parts: the optical fiber fixing piece adopts a die-casting mode, the cover shell 501 adopts a sheet metal part, the overall thickness of a product is only 2.42mm, and the packaging requirement of the SFP-DD optical module is met. A tail fiber sleeve 5041 is designed outside the optical fiber array, and is fixed on the optical fiber fixing member by glue during use, and the optical fiber fixing member is fixed on the cover shell 501 by the glue to protect the optical fiber array and the optical end face of the coherent optical chip from external force. The both sides design of metal lid shell 501 and optic fibre mounting bonding part has a plurality of recesses for glue is fixed, improves connection stability.

In order to improve the communication efficiency of light, in the coherent component 500 of the present example, the coherent modulator is a dual-polarization coherent modulator, the transmitted signal light is a coupled light beam of signal lights with different polarization directions, and the received signal light includes two groups of signal lights with different polarization directions, so as to implement single-channel multiple-signal transmission.

Fig. 42 is a schematic structural diagram of an exemplary coherent optical chip according to the present application, and as shown in the diagram, in a layout scheme of a high-speed coherent optical chip according to the present application, a silicon photonic integrated technology is adopted, a monolithic is integrated with dual-polarization coherent transmitting and receiving functions, and an optical fiber coupling port includes three optical fiber coupling ports, which are a receiving optical fiber coupling port 5111, a local oscillation optical fiber coupling port 5112, and a transmitting optical fiber coupling port 5113 from top to bottom. The local oscillator optical fiber coupling port 5112 is connected with an external local oscillator light source through a polarization-maintaining optical fiber, and light of the external local oscillator light source is divided into two beams after entering a chip, wherein one beam enters a dual-polarization coherent modulator as emitted light and is output from the emission optical fiber coupling port 5113 after being subjected to electro-optical signal loading and polarization rotation beam combiner 5141; the other beam of light, as local oscillator light, respectively enters the first polarization balance detector and the second polarization balance detector through beam splitting, and is optically mixed with the light which enters from the receiving optical fiber coupling port 5111 and is processed by the polarization rotation beam splitter, so that the demodulation processing of the signal is realized.

In order to facilitate the active coupling between the fiber coupling port and the fiber array, a transmitting coupling power monitor and a receiving coupling power monitor are integrated behind the polarization rotation beam combiner 5141 and the polarization rotation beam splitter respectively for performing the active coupling of the fiber array. At the receiving end, a small part of light is respectively split from the two beams of light passing through the polarization rotation beam splitter and enters the same receiving coupling power monitor for active coupling real-time monitoring, and at the transmitting end, a small part of light is respectively split from the two beams of light passing through the polarization rotation beam combiner 5141 and enters the same transmitting coupling power monitor for active coupling real-time monitoring. Meanwhile, in order to reduce the influence of different polarization states on the coupling power monitor and improve the precision of active coupling monitoring, a polarization beam splitter can be integrated in front of the coupling power monitor to improve the polarization purity of monitoring light, so that the precision of active coupling monitoring is improved.

And the optical fiber coupling port is arranged at the optical port of the coherent optical chip and is coupled and connected with the optical fiber connector. The fiber coupling port includes: a receive fiber coupling port 5111, a local oscillator fiber coupling port 5112, and a transmit fiber coupling port 5113. And the polarization balance receiver is connected with the receiving optical fiber coupling port 5111 and the local oscillation optical fiber coupling port 5112, and is used for converting the received signal light into a received electrical signal. And the dual-polarization coherent modulator is connected with the transmitting optical fiber coupling port 511 and the local oscillator optical fiber coupling port 5112, and is used for converting the transmitting electrical signal sent by the DSP chip into an optical signal and loading the optical signal into local oscillator light to form transmitting signal light.

The receiving optical fiber coupling port 5111 is connected to the receiving optical fiber adapter, and is configured to receive the signal light of the opposite end, and for convenience, the receiving optical fiber coupling port becomes receiving signal light, where the receiving signal light is a coupling beam of the first receiving signal light and the second receiving signal light with different polarization directions. The polarization rotation beam splitter 5121 is connected to the optical fiber coupling port through an optical waveguide, and is configured to divide the received signal light into a first received signal light and a second received signal light according to a difference in polarization direction. The local oscillator optical fiber coupling port 5112 receives local oscillator light emitted by the wavelength tunable optical component, and divides the local oscillator light into first sub local oscillator light and second sub local oscillator light through the optical waveguide, where the first sub local oscillator light is divided into first receiving local oscillator light and second receiving local oscillator light.

The first receiving local oscillator light and the first receiving signal light are optically coupled to enter the first polarization balance receiver 5123, the first polarization balance receiver 5123 performs frequency mixing and balance detection on the first receiving local oscillator light and the first receiving signal light, converts the first receiving signal light into a first receiving electric signal, and after the first receiving electric signal is amplified by the first receiving amplification chip, the first receiving local oscillator light and the first receiving signal light enter the DSP chip, and the first receiving electric signal is converted into a first receiving digital signal.

The second receiving local oscillator light and the second receiving signal light are optically coupled and enter the second polarization balanced receiver 5124, and the second polarization balanced receiver 5124 performs frequency mixing and balanced detection on the second receiving local oscillator light and the second receiving signal light, converts the second receiving signal light into a second receiving electric signal, amplifies the second receiving electric signal by the second receiving amplification chip, and then enters the DSP chip, and converts the second receiving electric signal into a second receiving digital signal.

In order to facilitate monitoring of the coupling accuracy of the receiving optical fiber and the receiving optical fiber coupling port 5111, when the coupling installation is performed, the test light is connected to the outside of the optical fiber coupling port, and includes the first test light, the second test light and the third test light, and in the process, the test light enters the coherent light chip from the outside of the coherent light chip. The coherent optical chip is further provided with a receiving coupling power monitor 5122, which receives part of light of the two light-emitting optical paths of the polarization rotation beam splitter 5121 to perform coupling power monitoring, the MCU is electrically connected to the receiving coupling power monitor 5122 to receive an electrical signal of the receiving coupling power monitor 5122, calculate the optical power of the optical fiber coupling port according to the electrical signal of the receiving coupling power monitor 5122, compare the optical power of the optical fiber coupling port with the optical power of the first test light, and adjust the coupling precision of the receiving optical fiber receiving coupler and the receiving optical fiber. Specifically, a first test optical power threshold interval is set in the MCU, and if the optical power of the optical fiber coupling port is not within the first test optical power threshold interval, the coupling precision of the receiving optical fiber and the receiving optical fiber coupling port 5111 needs to be adjusted.

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

In the present application, the node positions shown in the figure are to realize splitting of a part of light, for example, at the node 5125, an optical waveguide between the node 5125 and the first light outlet of the polarization rotation beam splitter 5121 is referred to as a first waveguide, an optical waveguide between the receive coupling power monitor 5122 and the node 5125 is referred to as a second waveguide, an optical waveguide between the first polarization balance receiver 5123 and the node 5125 is referred to as a third waveguide, for realizing splitting of light in the first light outlet of the polarization rotation beam splitter 5121, a directional coupler is arranged at the node, and the receive coupling power monitor 5122 is arranged between the node 5125 and the first polarization balance receiver 5123. Similarly, a receive coupled power monitor 5122 is disposed between the node 5126 and the second polarization balanced receiver 5124.

The dual-polarization coherent modulator 516, connected to the transmitting fiber coupling port 511 and the local oscillator fiber coupling port 5112 through optical waveguides, is configured to convert the transmitting electrical signal sent by the DSP chip into an optical signal, and load the optical signal into local oscillator light to form transmitting signal light.

In order to facilitate the active coupling between the fiber coupling port and the fiber array, a launch coupling power monitor is disposed between the two input ends of the polarization rotation beam combiner 5141.

In order to facilitate monitoring of coupling accuracy of the transmitting optical fiber and the transmitting optical fiber coupling port 511, during coupling installation, test light is connected outside the optical fiber coupling port, and includes first test light, second test light and third test light, in the process, the test light enters the coherent light chip from the outside of the coherent light chip, wherein the first test light enters from the receiving optical fiber coupling port 5111, the second test light enters from the local oscillation optical fiber coupling port 5112, and the third test light connects from the transmitting optical fiber coupling port 511. The coherent optical chip is further provided with a transmitting coupling power monitor 5143, the transmitting polarization rotation beam combiner 5141 transmits partial light at two input ends for monitoring coupling power, the MCU is electrically connected to the transmitting coupling power monitor 5143, receives an electrical signal of the transmitting coupling power monitor 5143, calculates the optical power of the transmitting fiber coupling port 511 according to the electrical signal of the transmitting coupling power monitor 5143, and compares the optical power of the transmitting fiber coupling port with the optical power of the third test light to adjust the coupling precision of the transmitting fiber receiving coupler and the transmitting fiber. Specifically, a second test optical power threshold interval is set in the MCU, and if the optical power of the transmitting optical fiber coupling port 511 is not within the second test optical power threshold interval, the coupling precision between the transmitting optical fiber and the transmitting optical fiber coupling port 511 needs to be adjusted.

Fig. 43 is a schematic structural diagram of a coherent optical chip according to an example of the present application, in order to reduce the influence of different polarization states on the coupling power monitor and improve the accuracy of active coupling monitoring, a first polarization beam splitter 5128 is disposed between the receiving coupling power monitor 5122 and the first light outlet of the polarization rotation beam splitter 5121, so as to prevent light that does not belong to the first polarization state from entering the receiving coupling power monitor 5122. Similarly, a second polarization beam splitter 5127 is disposed between the receiving coupling power monitor 5122 and the second light outlet of the polarization rotation beam splitter 5121, so as to prevent light not belonging to the second polarization state from entering the receiving coupling power monitor 5122.

In order to facilitate monitoring of the coupling accuracy of the receiving optical fiber and the receiving optical fiber coupling port 5111, when the coupling installation is performed, the testing light, which includes the first testing light, the second testing light and the third testing light, is connected to the outside of the optical fiber coupling port, and in the process, the testing light enters the coherent optical chip from the outside of the coherent optical chip. The first test light enters the coherent light chip through the receiving fiber coupling port 5111, and receives partial light of two light outgoing paths on the right side of the polarization rotation beam splitter 5121 to form first sub test light and second sub test light with different polarization directions, where if 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 a first path (above), then the partial test light enters the first polarization balance detector, and the partial test light enters the first polarization beam splitter 5128, the first polarization beam splitter 5128 may allow the X-polarized light in the light beam transmitted to the first polarization beam splitter 5128 to transmit, and the light in other directions is filtered out. The receiving polarization rotation beam splitter 5121 transmits the Y polarized light through the second path (below), and then a part of the Y polarized light enters the second polarization balanced detector, and a part of the Y polarized light enters the second polarization beam splitter, which allows the Y polarized light in the light beam transmitted to the second polarization beam splitter to transmit, and filters the 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, receives the electrical signal of the receiving coupling power monitor 5122, calculates the optical power of the fiber coupling port according to the electrical signal of the receiving coupling power monitor 5122, and compares the optical power of the fiber coupling port with the optical power of the first test light to adjust the coupling precision between the receiving fiber coupler and the receiving fiber. Specifically, a first test optical power threshold interval is set in the MCU, and if the optical power of the optical fiber coupling port is not within the first test optical power threshold interval, the coupling accuracy of the receiving optical fiber and the receiving optical fiber coupling port 5111 needs to be adjusted.

Similarly, in order to reduce the influence of different polarization states on the coupling power monitor and improve the accuracy of active coupling monitoring, a first transmitting polarization beam splitter 5161 is disposed between the transmitting coupling power monitor 5143 and the first input end of the polarization rotating beam combiner 5141, so as to prevent light that does not belong to the first polarization state from entering the receiving coupling power monitor 5122. A second receiving polarization beam splitter 5162 is disposed between the transmitting coupling power monitor 5143 and the second input end of the polarization rotation beam combiner 5141, so as to prevent light not belonging to the second polarization state from entering the receiving coupling power monitor 5122.

Continuing with fig. 42 and 43, in this example, in the working process, the local oscillator optical fiber coupling port 5112 receives local oscillator light emitted by the wavelength tunable optical component, and divides the local oscillator light into a first sub local oscillator light and a second sub local oscillator light through the optical waveguide, where the first sub local oscillator light is divided into a first receiving local oscillator light and a second receiving local oscillator light. The second receiving local oscillator light is divided into a first emitting light and a second emitting light, which enter two input ends of the dual-polarization coherent modulator 516, respectively.

For example, the dual-polarization coherent modulator 516 has a first optical input end for receiving the first emitting light and a second optical input end for receiving the second emitting light, and performs signal modulation on the first emitting light and the second emitting light respectively to output a first emitting signal light and a second emitting signal light. The polarization rotation beam combiner 5141 is connected to the first output end and the second output end of the dual-polarization coherent modulator 516, and rotates the first transmission signal light and the second transmission signal light into light beams with mutually perpendicular polarization directions, and couples and outputs the light beams as transmission signal light.

The first and second emitted light are of the same polarization direction and have different amplitudes and phases to load different signals. The polarization rotation beam combiner 5141 deflects one of the first or second emitted light, forms an angle of approximately 90 ° with the other light, and combines the deflected light and the other light into a single emitted signal light. The polarization rotation beam 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, the output end is connected to the transmitting fiber coupling port 511, and the transmitting signal light enters the transmitting fiber through the transmitting fiber coupling port 511.

The coherent optical chip further includes a first emission optical attenuator 5144, which is disposed between the polarization rotation beam combiner 5141 and the first polarization coherent modulator 5142, and performs attenuation control on the first emission signal light. To control the first emission light attenuator 5144, a first optical attenuator power monitor 5145 is disposed at a second output of the first emission light attenuator 5144, and a first output of the first emission light attenuator 5144 is connected to a first input of the emission polarization rotating beam combiner 5141. The MCU is electrically connected to the first optical attenuator power monitor 5145, and controls the output voltage to the first emission light attenuator 5144 via data collected by the first optical attenuator power monitor 5145.

To achieve more accurate monitoring of the emitted light power, a first emitted power monitor 5147 is disposed between the second output port of the first emitted light attenuator 5144 and the polarization rotating beam combiner 5141 for monitoring the light power of the attenuated first emitted signal light. The MCU is electrically connected to the first emission power monitor 5147, and the upper computer can read the optical power of the first emission signal light stored in the MCU.

Similarly, the coherent optical chip further includes a second transmitting optical attenuator 5154, which is disposed between the polarization rotation beam combiner 5141 and the second polarization coherent modulator 5152, and performs attenuation control on the second transmitting signal light. To control the second transmitting optical attenuator 5154, a second optical attenuator power monitor 5155 is disposed at a second output terminal of the second transmitting optical attenuator 5154, and a first output terminal of the second transmitting optical attenuator 5154 is connected to a second input terminal of the transmitting polarization rotation beam combiner 5141. The MCU is electrically connected to the second optical attenuator power monitor 5155, and controls an output voltage to the second transmitting optical attenuator 5154 through data collected by the second optical attenuator power monitor 5155.

To more accurately monitor the emitted optical power, a second emitted power monitor 5157 is disposed between the second emitted optical attenuator 5154 and the polarization rotation beam combiner 5141, and is used for monitoring the optical power of the attenuated second emitted signal light. The MCU is electrically connected with the second transmitting power monitor, and the upper computer can read the optical power of the second transmitting signal light stored in the MCU.

A first modulator power monitor 5146 is disposed between the first emission optical attenuator 5144 and the first polarization coherent modulator 5142 for monitoring the phase of the first emission signal light, and the first modulator power monitor 5146 is connected to the MCU. The MCU receives the monitoring data of the first modulator power monitor 5146, and performs phase modulation of the first transmission signal light.

Fig. 44 shows a layout of ball-planting on the surface of the coherent optical chip according to an example of the present application, as shown in fig. 44, wherein a dual-polarization coherent modulator conductive area 5171 and an optical fiber coupling port conductive area 5172 are respectively disposed on the upper and lower sides of the surface of the coherent optical chip, a first polarization balanced receiver conductive area 5173 and a second polarization balanced receiver conductive area 5174 are disposed on the left side of the coherent optical chip, other dc signal ball-planting areas are disposed around the coherent optical chip to facilitate signal interconnection with an external electrical chip, and the middle portion of the coherent optical chip is uniformly ball-planted and filled to improve reliability and stability of the 2.5D flip chip package.

In order to facilitate the coupling and packaging of the optical fiber array and the optical fiber coupling port, the distance between the ball-planting around the optical fiber coupling port and the optical fiber coupling port is required to be greater than 0.5mm. The optical fiber coupling port comprises five coupling optical ports which are respectively a receiving coupling optical port, a local oscillator coupling optical port and an emitting coupling optical port from left to right, and two optical ports on the right side are loopback testing optical ports for coupling testing. In order to improve the coupling efficiency with FA and the coupling reworkability, the optical fiber coupler adopts a silicon nitride material and direct scribing and dissociation mode to ensure the verticality of the end face of the optical fiber coupling port.

In some examples of the present application, as shown in fig. 45 and 46, an input end of the first local oscillator optical splitter 5131 is connected to the local oscillator optical fiber coupling port, a first output end of the first local oscillator optical splitter 5131 is connected to the first polarization coherent modulator 5412, and a second output end of the first local oscillator optical splitter 5132 is connected to an input end of the second local oscillator optical splitter; a first output end of the second local oscillation optical splitter 5132 is connected to the second polarization coherent modulator 5152, and a second output end is connected to an input end connected to the third local oscillation optical splitter 5133; a first output end of the third local oscillator beam splitter 5133 is connected to the first polarization balanced receiver, and a second output end is connected to the second polarization balanced receiver. The optical fiber coupling device can also be set as a first local oscillation optical splitter, the input end of the first local oscillation optical splitter is connected with the local oscillation optical fiber coupling port, the first output end of the first local oscillation optical splitter is connected with the input end of a second local oscillation optical splitter, and the second output end of the first local oscillation optical splitter is connected with the input end of a third local oscillation optical splitter; a first output end of the third local oscillator optical splitter is connected with the first polarization coherent modulator, and a second output end of the third local oscillator optical splitter is connected with the first polarization coherent modulator; the first output end of the second local oscillator optical splitter is connected with the first polarization balance receiver, and the second output end of the second local oscillator optical splitter is connected with the second polarization balance receiver.

In the above coherent optical chip, in order to increase the effective emitted optical power and ensure that the optical powers of the emitted light output by the polarization coherent modulators in two different directions are substantially consistent, in the present application, power splitters are used at the first local oscillator optical splitter 5131, the second local oscillator optical splitter 5132, and the third local oscillator optical splitter 51333 to split the light into two beams, as shown in fig. 44. After entering the chip, the light of the external local oscillation light source is divided into two beams with optical power of 50% and 50% respectively at the first local oscillation optical splitter 5131, wherein one beam is equally divided into two beams at the fourth local oscillation optical splitter 5134 as the emitted light, and the two beams enter the first polarization coherent modulator and the second polarization coherent modulator respectively, and are output from the emission optical fiber coupling port 5113 after being subjected to electro-optical signal loading and polarization processing by the polarization rotation beam combiner 5141; the other beam of light is split by the third local oscillation beam splitter 5133 again and enters the first polarization balance detector 5123 and the second polarization balance detector 5124 respectively as local oscillation light, and is optically mixed with the light which enters from the receiving optical fiber coupling port 5111 and is processed by the polarization rotation beam splitter 5121.

The optical power is divided into two beams of 50% and 50% at the first local oscillation optical splitter 5131, wherein one beam is equally divided into two beams at the fourth local oscillation optical splitter 5134 as the transmission light, and the two beams enter the first polarization coherent modulator 5142 and the second polarization coherent modulator 5152, so that the optical power of the light entering the first polarization coherent modulator and the second polarization coherent modulator is the same.

In order to avoid the problem that the difference between the output optical powers of the first polarization coherent modulator and the second polarization coherent modulator is large due to different optical losses of different coherent modulators in the modulation process, a first transmission optical attenuator 5144 is further arranged between the polarization rotation beam combiner 5141 and the first polarization coherent modulator 5142 to perform attenuation control on the first transmission signal light. To control the first emission light attenuator 5144, a first optical attenuator power monitor 5145 is disposed at a second output of the first emission light attenuator 5144, and a first output of the first emission light attenuator 5144 is connected to a first input of the emission polarization rotating beam combiner 5141. The MCU is electrically connected to the first optical attenuator power monitor 5145, and controls the output voltage to the first emission light attenuator 5144 via data collected by the first optical attenuator power monitor 5145.

A first emission power monitor 5147 is disposed between the second output port of the first emission optical attenuator 5144 and the polarization rotation beam combiner 5141, and is used for monitoring the optical power of the attenuated first emission signal light. The MCU is electrically connected to the first emission power monitor 5147, and the upper computer can read the optical power of the first emission signal light stored in the MCU.

The coherent optical chip is further provided with a second transmitting optical attenuator 5154, which is disposed between the polarization rotation beam combiner 5141 and the second polarization coherent modulator 5152, and performs attenuation control on the second transmitting signal light. To control the second transmitting optical attenuator 5154, a second optical attenuator power monitor 5155 is disposed at a second output terminal of the second transmitting optical attenuator 5154, and a first output terminal of the second transmitting optical attenuator 5154 is connected to a second input terminal of the transmitting polarization rotation beam combiner 5141. The MCU is electrically connected to the second optical attenuator power monitor 5155, and controls an output voltage to the second transmitting optical attenuator 5154 through data collected by the second optical attenuator power monitor 5155.

A second transmission power monitor 5157 is disposed between the second transmission optical attenuator 5154 and the polarization rotation beam combiner 5141, and is configured to monitor the optical power of the attenuated second transmission signal light. The MCU is electrically connected with the second transmitting power monitor, and the upper computer can read the optical power of the second transmitting signal light stored in the MCU.

In order to increase the effective emitted light power, the ratio of the difference between the light powers of the emitted light output by the two polarization coherent modulators in different directions should be no more than 15%, i.e. the ratio of the difference between the first polarization coherent modulator and the second polarization coherent modulator to the first polarization coherent modulator or the second polarization coherent modulator is no more than 15%.

The MCU can control the magnitude of the attenuation value of the first optical attenuator or the second optical attenuator by monitoring the optical power of the first transmitting signal light and the optical power of the second transmitting 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.

The present application further provides another embodiment, where the first local oscillator optical splitter 5131 and the fourth local oscillator optical splitter 5134 are adjustable optical splitters, and the size of the emitted optical power can be controlled by controlling the splitting ratio of the output ends of the first local oscillator optical splitter and the third local oscillator optical splitter. In order to improve the effective emitted light power and ensure that the light powers of the emitted lights output by the polarization coherent modulators in two different directions are basically consistent, the difference ratio of the output light power of the first polarization coherent modulator to the output light power of the second polarization coherent modulator is controlled to be not more than 15%.

In the above coherent optical chip, the insertion loss of the optical fiber coupling port and the polarization rotation beam combiner 5141 to light with different polarization states may be different, especially the optical insertion loss of the optical fiber coupling port may also be affected by the chip processing technology, and in practical application, the power balance of two light with different polarizations emitted from the emitting end is required, so that the present application provides another coherent optical chip structure schematic diagram, and the power attenuation is performed on the light power with higher power in the polarization state by the adjustable optical attenuator integrated on the coherent optical chip, thereby reducing the effective light emitting power and affecting the chip yield. Fig. 47 is a schematic structural diagram of a coherent optical chip provided by the present application, where as shown in fig. 47, the optical fiber coupler includes three optical fiber coupling ports, which are, from top to bottom, a receiving optical fiber coupling port 5111, a local oscillation optical fiber coupling port 5112, and a transmitting optical fiber coupling port 511. The local oscillator optical fiber coupling port 5112 is connected to an external local oscillator light source through a polarization maintaining optical fiber. The first local oscillator optical splitter 5131 is an unbalanced optical splitter, the input end of which is connected to the local oscillator optical 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 optical splitter. A first output end of the second local oscillation optical splitter 5132 is connected to the second polarization coherent modulator, and a second output end is connected to an input end of the third local oscillation optical splitter. A first output terminal of the third local oscillation optical splitter 5133 is connected to the first polarization balanced receiver 5123, and a second output terminal thereof is connected to the second polarization balanced receiver 5124.

Light of an external local oscillator light source enters a coherent light chip and is divided into two beams by an unbalanced beam splitter, wherein one beam enters a first polarization coherent modulator 5142 as emitted light, and is output from an emission optical fiber coupling port 5113 after being subjected to electro-optical signal loading and polarization processing by a polarization rotation beam combiner 5141; another beam of light is split into two beams as local oscillator light again by the second local oscillator beam splitter 5132, one beam of light enters the second polarization coherent modulator 5152 as transmission light, is output from the transmission optical fiber coupling port 511 after being subjected to polarization processing by the electro-optical signal loading and polarization rotation beam combiner 5141, the other output port of the second local oscillator beam splitter 5132 is connected with the input end of the third local oscillator beam splitter 5133, is split into two beams by the third local oscillator beam splitter, and respectively enters the first polarization balance detector 5123 and the second polarization balance detector 5124, and is subjected to optical frequency mixing with the light which is input from the reception optical fiber coupling port 5111 and is processed by the polarization rotation beam splitter 5121, so that signal demodulation processing is realized.

After the light of the external local oscillator light source enters the coherent chip, the specific light splitting process is as follows: the light split by the non-equilibrium splitter in a certain proportion enters the first polarization coherent modulator (for example, 40%), the split proportion can be designed differently according to the power difference between the first and second different polarization emitted lights, and in addition, 60% of the light enters the second local oscillator splitter 5132. The two polarization beams are uniformly split into two parts by the second local oscillator optical splitter 5132, one of the two polarization beams is connected to the second polarization coherent modulator 5152, and the other polarization beam enters the third local oscillator optical splitter 5133.

In an actual chip design, different structural designs can be performed on the splitting ratio of the unbalanced splitter according to the difference between the output optical powers of the first polarization coherent modulator and the second polarization coherent modulator, so that the two polarized optical powers of the first angle and the second angle in the light beam emitted from the emission optical fiber coupling port 5113 are balanced, and the effective light emission power is improved. The non-uniform optical splitter is usually designed by adopting an optical splitter structure with an asymmetric waveguide structure.

The output end of the polarization rotation beam 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.

In the present application example, the non-uniform optical splitter may adopt an optical splitter structure design with an asymmetric waveguide structure, and may also use a device based on a mach-zehnder interference type structure, as shown in fig. 46. A heater is integrated above the Mach-Zehnder interference type structure, and the light splitting proportion of the unbalanced light splitter can be changed by adjusting the heater. In actual work, the light splitting ratio of the unbalanced light splitter can be adjusted in real time according to the output light power of the second polarization coherent modulator, so that the two polarized light powers in the light beam emitted from the emission coupling port are balanced, the effective light emission power is improved, and the chip yield is improved.

Fig. 48 is a schematic structural diagram of an unbalanced splitter according to an embodiment of the present application. As shown in fig. 48, the unbalanced splitter includes: the optical fiber coupling device comprises a first sub-light splitting component, a modulation arm, an interference arm and a second sub-light splitting component, wherein the input end of the first sub-light splitting component is connected with a local oscillation optical fiber coupling port to divide local oscillation light into two beams. The first output end of the first sub-splitting part is connected with the modulation arm, and the second output end is connected with the interference arm. The first input end of the third sub-splitting component is connected with the output end of the modulation arm, the second input end is connected with the output end of the interference arm, the first output end is connected with the input end of the second local oscillator splitter 5132, and the second output end is connected with the first polarization coherent modulator 5142. The MCU is electrically connected with the first modulation arm and the second modulation arm, and the temperature of the modulation arms is controlled through the output voltage so as to control the refractive index of the modulation arms and realize the light splitting of two output ends of the non-equilibrium light splitter.

Fig. 49 is a schematic structural diagram six of a coherent optical chip provided in this application, in this application example, the coherent optical chip further includes: the coherent optical chip is further provided with a first emission optical attenuator 5144, which is disposed between the polarization rotation beam combiner 5141 and the first polarization coherent modulator, and performs attenuation control on the first emission signal light. To control the first emission light attenuator 5144, a first optical attenuator power monitor 5145 is disposed at a first output of the first emission light attenuator 5144, and a first output of the first emission light attenuator 5144 is connected to a first input of the emission polarization rotating beam combiner 5141. The MCU is electrically connected to the first optical attenuator power monitor 5145, and controls the output voltage to the first transmission optical attenuator 5144 through data collected by the first optical attenuator power monitor 5145.

Fig. 50 is a schematic structural diagram of a coherent optical chip according to an example of the present application, and as shown in fig. 50, in order to monitor the effective optical transmission power and calculate the splitting ratio of the non-uniform splitter, a first transmission power monitor 5147 is disposed between the first transmission optical attenuator 5144 and the polarization rotation beam combiner 5141 in the coherent optical chip for monitoring the optical power of the attenuated first transmission signal light. The MCU is electrically connected to the first emission power monitor 5147, and the upper computer can read the optical power of the first emission signal light stored in the MCU.

Similarly, in order to more accurately monitor the transmitted optical power, a second transmitted power monitor is disposed between the second transmitting optical attenuator and the polarization rotation beam combiner 5141, and is used for monitoring the optical power of the attenuated second transmitting signal light. The MCU is electrically connected with the second emission power monitor, and the upper computer can read the optical power of the second emission signal light stored in the MCU.

And the light splitting proportion of the non-equilibrium light splitter is regulated and controlled according to the data collected by the second emission power monitor 5157 and the first emission power monitor 5147.

The non-uniform splitter may also utilize devices based on mach-zehnder interference type structures. A heater is integrated above the Mach-Zehnder interference type structure, and the light splitting proportion of the non-equilibrium light splitter can be changed by adjusting the heater. In actual work, the light splitting ratio of the unbalanced light splitter can be adjusted in real time according to the output optical power of the second polarization coherent modulator, so that the two polarized optical powers in the light beam emitted from the emission optical fiber coupling port 511 and the emission optical fiber coupling port 5115113 are balanced, thereby improving the effective light emission power and improving the yield of chips.

In the coherent optical module in this example, an input end of the non-equilibrium optical splitter is connected to the local oscillation fiber coupling port 5112, a first output end is connected to the first polarization coherent modulator, and a second output end is connected to an input end of the second local oscillation optical splitter. The first output end of the second local oscillator optical splitter is connected with the second polarization coherent modulator, and the second output end of the second local oscillator optical splitter is connected with the input end of the third local oscillator optical splitter. The first output terminal of the third local oscillator splitter is connected to the first polarization balanced receiver 5123, and the second output terminal is connected to the second polarization balanced receiver 5124.

Further, in order to achieve the optical power balance of two different polarizations, the second local oscillation optical splitter 5132-bit adjustable optical splitter can perform the splitting adjustment of the adjustable optical splitter according to the difference between the output optical powers of the first polarization coherent modulator and the second polarization coherent modulator. When the output optical power of the first polarization coherent modulator is greater than the output optical power of the second polarization coherent modulator, adjusting the light output proportion of the second output end of the adjustable light splitter to increase, so that the optical power of the second emitted light entering the second polarization coherent modulator increases, and the difference value between the output optical power of the first polarization coherent modulator and the output optical power of the second polarization coherent modulator is reduced.

And when the output optical power of the first polarization coherent modulator is smaller than that of the second polarization coherent modulator, adjusting the light-emitting proportion of the second output end of the adjustable optical splitter to be reduced. The optical power of the second emitted light entering the second polarization coherent modulator is reduced, 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.

It should be noted that, in the present specification, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a circuit structure, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such circuit structure, article, or apparatus. Without further limitation, the statement "comprises a" \8230; "8230;" defines an element and does not exclude the presence of additional like elements in circuit structures, articles, or devices comprising the element.

Other embodiments of the present application will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure herein. This application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the application and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the application being indicated by the following claims.

The above-described embodiments of the present application do not limit the scope of the present application.

The above description is only for the specific embodiments of the present disclosure, but the scope of the present disclosure is not limited thereto, and any person skilled in the art will appreciate that changes or substitutions within the technical scope of the present disclosure are included in the scope of the present disclosure. Therefore, the protection scope of the present disclosure shall be subject to the protection scope of the claims.

Claims

1. A light module, comprising:

coherent optical chip, with optical fiber splice coupling connection, include:

the polarization rotation beam splitter is arranged on one side of the receiving optical fiber coupling port and is used for splitting the receiving signal light into a first receiving signal light and a second receiving signal light according to different deflection angles;

the input end of the non-equilibrium optical splitter is connected with the coupling port of the local oscillator, the first output end of the non-equilibrium optical splitter is connected with the first polarization coherent modulator, and the second output end of the non-equilibrium optical splitter is connected with the input end of the second local oscillator;

a first output end of the second local oscillator optical splitter is connected with the second polarization coherent modulator, and a second output end of the second local oscillator optical splitter is connected with an input end connected with the third local oscillator optical splitter;

the optical power of the input end of the first polarization coherent modulator is different from the optical power of the input end of the second polarization coherent modulator;

the difference between the optical power output by the first polarization coherent modulator and the optical power output by the second polarization coherent modulator is not more than 15%;

and the transmitting optical fiber coupling port is connected with the first polarization coherent modulator and the second polarization coherent modulator and used for outputting transmitting signal light.

2. The light module of claim 1, comprising:

the first polarization balance receiver is connected with a first output port of the polarization rotation beam splitter and a first output port of the third local oscillation beam splitter;

and the second polarization balance receiver is connected with a second output port of the polarization rotation beam splitter and a second output port of the third local oscillation beam splitter.

3. The optical module of claim 2, wherein the non-uniform splitter is a mach-zehnder interferometer comprising: a first sub-spectroscopic part, a modulation arm, an interference arm, and a second sub-spectroscopic part, wherein:

the input end of the first sub-splitting component is connected with the local oscillation optical fiber coupling port to divide the local oscillation light into two beams;

the first output end of the first sub-splitting component is connected with the modulation arm, and the second output end of the first sub-splitting component is connected with the interference arm;

the first input end of the third sub-light splitting component is connected with the output end of the modulation arm, the second input end of the third sub-light splitting component is connected with the output end of the interference arm, the first output end of the third sub-light splitting component is connected with the input end of the second local oscillator light splitter, and the second output end of the third sub-light splitting component is connected with the first polarization coherent modulator.

4. The optical module of claim 2, further comprising an MCU electrically connected to the non-equalizing splitter for controlling a splitting ratio of the non-equalizing splitter.

5. The optical module of claim 2, wherein the coherent optical chip further comprises:

and a first input port of the polarization rotation beam combiner is connected with the output end of the first polarization coherent modulator, a second input port of the polarization rotation beam combiner is connected with the output end of the second polarization coherent modulator, and a beam combining port of the polarization rotation beam combiner is connected with a coupling port of the transmitting optical fiber and is used for deflecting the polarization direction of the first transmitting signal light and combining the first transmitting signal light and the second transmitting signal light to form transmitting signal light.

6. The optical module of claim 5, wherein the local oscillator fiber coupling port is disposed between the transmit fiber coupling port and the receive fiber coupling port.

7. The optical module of claim 5, wherein the coherent optical chip further comprises: the first transmission power monitor is arranged between the first coherent modulator and the polarization rotation beam combiner and is used for monitoring the transmission optical power of the first coherent modulator;

and the second transmitting power monitor is arranged between the second coherent modulator and the polarization rotation beam combiner and is used for monitoring the transmitting optical power of the second coherent modulator.

8. The optical module of claim 1, further comprising: the coherent optical fiber piece is arranged on the support plate;

the transmitting driving chip is arranged on the carrier plate and is positioned on the opposite side of the local oscillation optical fiber;

the first receiving amplification chip is positioned on the carrier plate and is electrically connected with the first polarization balance receiver;

and the second receiving amplification chip is positioned on the carrier plate and is electrically connected with the first polarization balance receiver.

9. The light module of claim 8, further comprising: the circuit board is arranged on the carrier plate;

the circuit board is also provided with a DSP chip which is electrically connected with the coherent optical chip.