CN214954237U - Optical module - Google Patents

Abstract

The optical module comprises a circuit board, a light source, a silicon optical chip, an optical fiber ribbon and an optical fiber connector, wherein the light source is used for generating light beams; the silicon optical chip is arranged on the circuit board and comprises an optical output waveguide used for modulating the light beam into signal light; the optical fiber ribbon comprises a first optical fiber, a second optical fiber and a third optical fiber, the light source is connected with the silicon optical chip through the third optical fiber, and the silicon optical chip is connected with the optical fiber connector through the first optical fiber and the second optical fiber so as to realize the receiving and sending of light. When the first optical fiber is coupled with the silicon optical chip, a gap exists between the light-emitting surface of the light output waveguide and the optical fiber end surface of the first optical fiber, and the light return loss of the light output waveguide is easily caused.

Description

Optical module

Technical Field

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

Background

With the development of new services and application modes such as cloud computing, mobile internet, video and the like, the development and progress of the optical communication technology become increasingly important. In the optical communication technology, an optical module is a tool for realizing the interconversion of optical signals and is one of key devices in optical communication equipment, and the transmission rate of the optical module is continuously increased along with the development requirement of the optical communication technology.

Existing light modules may generally include: the optical fiber ribbon can input optical signals to the silicon optical chip and also can receive optical signals output by the silicon optical chip. When the silicon optical chip is coupled with the optical fiber ribbon, the optical interface of the silicon optical chip, the end face of the optical fiber ribbon coupled with the light source, the end face of the optical interface and the like can be reflected, so that the optical return loss of the optical module exceeds the standard, and the transmission performance of the optical module is influenced.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides an optical module to solve the problem that the optical return loss of the optical module exceeds the standard due to reflection at optical interfaces among devices in the existing optical module.

In a first aspect, the present application provides an optical module, comprising:

a circuit board;

a light source for generating a light beam;

the silicon optical chip is arranged on the circuit board and comprises an optical output waveguide; the light output waveguide is used for transmitting the signal light out;

the optical fiber ribbon comprises a first optical fiber, a second optical fiber and a third optical fiber, wherein one end of the first optical fiber is coupled with a light-emitting surface of the optical output waveguide, a gap is formed between the light-emitting surface of the optical output waveguide and the optical fiber end surface of the first optical fiber, an acute angle is formed between the light-emitting surface of the optical output waveguide and the optical fiber end surface of the first optical fiber, and an antireflection film is arranged on one side, facing the light-emitting surface, of the optical fiber end surface; one end of the second optical fiber is coupled with the light inlet of the silicon optical chip to realize the light receiving; the light source is connected with the silicon optical chip through the third optical fiber;

and the optical fiber connector is connected with the other end of the first optical fiber and the other end of the second optical fiber.

In a second aspect, the present application provides a light module comprising:

a circuit board;

a light source for generating a light beam;

the silicon optical chip is arranged on the circuit board and comprises an optical input waveguide; for converting the optical signal into an electrical signal;

the optical fiber ribbon comprises a first optical fiber, a second optical fiber and a third optical fiber, wherein one end of the first optical fiber is coupled and connected with the light outlet of the silicon optical chip so as to realize light emission; one end of the second optical fiber is coupled with the light incident surface of the light input waveguide, a gap exists between the light incident surface of the light input waveguide and the optical fiber end surface of the second optical fiber, an acute angle is formed between the light incident surface of the light input waveguide and the optical fiber end surface of the second optical fiber, and an antireflection film is arranged on one side, facing the second optical fiber, of the light incident surface of the light input waveguide; the light source is connected with the silicon optical chip through the third optical fiber;

and the optical fiber connector is connected with the other end of the first optical fiber and the other end of the second optical fiber.

The optical module provided by the application comprises a circuit board, a light source, a silicon optical chip, an optical fiber ribbon and an optical fiber connector, wherein the light source is used for generating light beams according to a power supply circuit of the circuit board; the silicon optical chip is arranged on the circuit board and comprises an optical output waveguide which is used for modulating the light beam into signal light and emitting the signal light out through the optical output waveguide; the optical fiber ribbon comprises a first optical fiber, a second optical fiber and a third optical fiber, wherein one end of the third optical fiber is connected with the light source, and the other end of the third optical fiber is coupled with the silicon optical chip so as to transmit the light beam to the silicon optical chip and modulate the light beam into signal light through the silicon optical chip; one end of the first optical fiber is coupled with the silicon optical chip, and the other end of the first optical fiber is connected with the optical fiber connector, so that the modulated signal light is transmitted to the optical fiber connector, and the light emission is realized; one end of the second optical fiber is coupled with the silicon optical chip, and the other end of the second optical fiber is connected with the optical fiber connector, so that the signal light received by the optical fiber connector is transmitted into the silicon optical chip and is converted into an electric signal through the silicon optical chip, and the light is received. When the silicon optical chip is coupled with the first optical fiber, a gap exists between the light-emitting surface of the optical output waveguide in the silicon optical chip and the optical fiber end surface of the first optical fiber, when signal light is emitted from the light-emitting surface to the optical fiber end surface, the signal light is easily reflected at the optical fiber end surface of the first optical fiber due to the change of a medium, and the reflected signal light enters the optical output waveguide again, so that the optical return loss of the optical interface of the silicon optical chip is caused. According to the optical waveguide, a certain angle is formed between the light-emitting surface of the optical output waveguide and the optical fiber end surface of the first optical fiber, so that the emergent angle of signal light during reflection on the optical fiber end surface can be changed, and the reflected signal light cannot enter the optical output waveguide; the anti-reflection film is additionally arranged on one side, facing the light output waveguide, of the fiber end face of the first optical fiber, when signal light emitted by the light output waveguide enters the first optical fiber, the penetrability of the fiber end face is improved through the anti-reflection film, the signal light directly enters the first optical fiber through the fiber end face and does not reflect at the fiber end face, so that the reflected signal light does not enter the optical waveguide, the light return loss at the light interface of the silicon optical chip can be effectively reduced, and the transmission performance of the optical module is improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic diagram of a connection relationship of an optical communication terminal;

FIG. 2 is a schematic diagram of an optical network unit;

fig. 3 is a schematic structural diagram of an optical module according to an embodiment of the present disclosure;

fig. 4 is an exploded structural diagram of an optical module according to an embodiment of the present disclosure;

fig. 5 is an assembly schematic diagram of a circuit board, a silicon optical chip, an optical fiber ribbon and an optical interface in an optical module according to an embodiment of the present application;

FIG. 6 is a schematic diagram illustrating an assembly of a circuit board, a silicon optical chip, an optical fiber ribbon and an optical interface at another angle in an optical module according to an embodiment of the present application;

fig. 7 is a schematic connection diagram of a silicon optical chip, a light source, an optical fiber ribbon and an optical interface in an optical module according to an embodiment of the present application;

fig. 8 is a schematic cross-sectional structure diagram of a silicon optical chip in an optical module according to an embodiment of the present disclosure;

fig. 9 is a schematic diagram illustrating a coupling between a silicon optical circuit chip and a first optical fiber in an optical module according to an embodiment of the present disclosure;

fig. 10 is a side view of a coupling between a silicon optical circuit chip and a first optical fiber in an optical module according to an embodiment of the present disclosure;

FIG. 11 is a first schematic diagram of an exemplary optical transmission path between a silicon optical circuit chip and a first optical fiber;

FIG. 12 is a second exemplary optical transmission path diagram of a silicon optical circuit chip and a first optical fiber;

fig. 13 is a structural side view of a silicon optical circuit chip in an optical module according to an embodiment of the present disclosure;

fig. 14 is a first schematic diagram illustrating an optical transmission path between a silicon optical circuit chip and a first optical fiber in an optical module according to an embodiment of the present disclosure;

fig. 15 is a side view of a partial structure of a first optical fiber in an optical module according to an embodiment of the present disclosure;

fig. 16 is a second schematic diagram of an optical transmission path between a silicon optical circuit chip and a first optical fiber in an optical module according to an embodiment of the present disclosure;

fig. 17 is a third schematic diagram of an optical transmission path between a silicon optical circuit chip and a first optical fiber in an optical module according to an embodiment of the present application;

fig. 18 is a fourth schematic diagram of an optical transmission path between a silicon optical circuit chip and a first optical fiber in an optical module according to the embodiment of the present application;

fig. 19 is a fifth schematic view of an optical transmission path between a silicon optical circuit chip and a first optical fiber in an optical module according to an embodiment of the present application;

FIG. 20 is a schematic diagram of an exemplary silicon photonic chip and optical transmission path of a second optical fiber.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

One of the core links of optical fiber communication is the interconversion of optical and electrical signals. The optical fiber communication uses optical signals carrying information to transmit in information transmission equipment such as optical fibers/optical waveguides, and the information transmission with low cost and low loss can be realized by using the passive transmission characteristic of light in the optical fibers/optical waveguides; meanwhile, the information processing device such as a computer uses an electric signal, and 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, it is necessary to perform interconversion between the electric signal and the optical signal.

The optical module realizes the function of interconversion of optical signals and electrical signals in the technical field of optical fiber communication, and the interconversion of the optical signals and the electrical signals is the core function of the optical module. The optical module is electrically connected with an external upper computer through a golden finger on an internal circuit board of the optical module, and the main electrical connection comprises power supply, I2C signals, data signals, grounding and the like; the electrical connection mode realized by the gold finger has become the mainstream connection mode of the optical module industry, and on the basis of the mainstream connection mode, the definition of the pin on the gold finger forms various industry protocols/specifications.

Fig. 1 is a schematic diagram of connection relationship of an optical communication terminal. As shown in fig. 1, the connection of the optical communication terminal mainly includes the interconnection among the optical network terminal 100, the optical module 200, the optical fiber 101 and the network cable 103;

one end of the optical fiber 101 is connected with a far-end server, one end of the network cable 103 is connected with local information processing equipment, and the connection between the local information processing equipment and the far-end server is completed by the connection between the optical fiber 101 and the network cable 103; and the connection between the optical fiber 101 and the network cable 103 is made by the optical network terminal 100 having the optical module 200.

An optical port of the optical module 200 is externally accessed to the optical fiber 101, and establishes bidirectional optical signal connection with the optical fiber 101; an electrical port of the optical module 200 is externally connected to the optical network terminal 100, and establishes bidirectional electrical signal connection with the optical network terminal 100; the optical module realizes the interconversion of optical signals and electric signals, thereby realizing the establishment of information connection between the optical fiber and the optical network terminal; specifically, the optical signal from the optical fiber is converted into an electrical signal by the optical module and then input to the optical network terminal 100, and the electrical signal from the optical network terminal 100 is converted into an optical signal by the optical module and input to the optical fiber.

The optical network terminal is provided with an optical module interface 102, which is used for accessing an optical module 200 and establishing bidirectional electric signal connection with the optical module 200; the optical network terminal is provided with a network cable interface 104, which is used for accessing the network cable 103 and establishing bidirectional electric signal connection with the network cable 103; the optical module 200 is connected to the network cable 103 through the optical network terminal 100, specifically, the optical network terminal transmits a signal from the optical module to the network cable and transmits the signal from the network cable to the optical module, and the optical network terminal serves as an upper computer of the optical module to monitor the operation of the optical module.

At this point, a bidirectional signal transmission channel is established between the remote server and the local information processing device through the optical fiber, the optical module, the optical network terminal and the network cable.

Common information processing apparatuses include routers, switches, electronic computers, and the like; the optical network terminal is an upper computer of the optical module, provides data signals for the optical module, and receives the data signals from the optical module, and the common upper computer of the optical module also comprises an optical line terminal and the like.

Fig. 2 is a schematic diagram of an optical network terminal structure. As shown in fig. 2, the optical network terminal 100 has a circuit board 105, and a cage 106 is disposed on a surface of the circuit board 105; an electric connector is arranged in the cage 106 and used for connecting an electric port of an optical module such as a golden finger; the cage 106 is provided with a heat sink 107, and the heat sink 107 has a projection such as a fin that increases a heat radiation area.

The optical module 200 is inserted into the optical network terminal, specifically, the electrical port of the optical module is inserted into the electrical connector inside the cage 106, and the optical port of the optical module is connected to the optical fiber 101.

The cage 106 is positioned on the circuit board, and the electrical connector on the circuit board is wrapped in the cage, so that the electrical connector is arranged in the cage; the optical module is inserted into the cage, held by the cage, and the heat generated by the optical module is conducted to the cage 106 and then diffused by the heat sink 107 on the cage.

Fig. 3 is a schematic view of an optical module according to an embodiment of the present disclosure, and fig. 4 is a schematic view of an exploded structure of an optical module according to an embodiment of the present disclosure. As shown in fig. 3 and 4, the difference from the optical module structure provided in the foregoing embodiment is that in this embodiment, the silicon optical chip 400 is used to replace the optical transceiver to implement the optical-to-electrical conversion of the optical module. Specifically, the optical module 200 provided in the embodiment of the present application includes an upper housing 201, a lower housing 202, an unlocking member 203, a circuit board 300, a silicon optical chip 400, an optical fiber ribbon 500, a light source 600, and an optical fiber connector 700.

The upper shell 201 is covered on the lower shell 202 to form a wrapping cavity with two openings; the outer contour of the wrapping cavity is generally a square body, and specifically, the lower shell comprises a main plate and two side plates which are positioned at two sides of the main plate and are perpendicular to the main plate; the upper shell comprises a third shell, and the third shell covers the two side plates of the upper shell to form a wrapping cavity; the upper shell can also comprise two side walls which are positioned on two sides of the third shell and are perpendicular to the third shell, and the two side walls are combined with the two side plates to cover the upper shell on the lower shell.

The two openings may be two ends (204, 205) in the same direction, or two openings in different directions; one opening is an electric port 204, and a gold finger of the circuit board extends out of the electric port 204 and is inserted into an upper computer such as an optical network terminal; the other opening is an optical port 205 for external optical fiber access to connect the silicon optical chip 400 inside the optical module; the photoelectric devices such as the circuit board 300, the silicon optical chip 400, the optical fiber ribbon 500, the light source 600, the optical fiber connector 700 and the like are positioned in the packaging cavity.

The assembly mode of combining the upper shell and the lower shell is adopted, so that the circuit board 300, the silicon optical chip 400, the optical fiber ribbon 500, the light source 600, the optical fiber connector 700 and other devices can be conveniently installed in the shells, and the outermost packaging protection shell of the optical module is formed by the upper shell and the lower shell; the upper shell and the lower shell are made of metal materials generally, so that electromagnetic shielding and heat dissipation are facilitated; generally, the housing of the optical module is not made into an integrated component, so that when devices such as a circuit board and the like are assembled, the positioning component, the heat dissipation component and the electromagnetic shielding component cannot be installed, and the production automation is not facilitated.

The circuit board 300 has a power supply circuit and a signal circuit for power supply and signal electrical connection. The optical fiber connector 700 includes an optical interface disposed at the optical port 205 of the optical module 200, and is used for receiving the optical signal converted from the electrical signal from the circuit board 300, transmitting the optical signal, and transmitting the optical signal to the circuit board 300. The optical module is characterized in that an optical port plug is arranged at one end of the optical interface and is connected with the optical interface in an embedded mode, and the optical port plug plays a role in sealing when the optical module is not used, so that dust pollution caused by long-time exposure is avoided. The smooth mouth stopper can adopt the rubber material, has the flexibility, can play fine sealed effect.

The unlocking component 203 is located on the outer wall of the wrapping cavity/lower shell 202, and is used for realizing the fixed connection between the optical module and the upper computer or releasing the fixed connection between the optical module and the upper computer.

The unlocking component 203 is provided with a clamping component matched with the upper computer cage; the end of the unlocking component can be pulled to enable the unlocking component to move relatively on the surface of the outer wall; the optical module is inserted into a cage of the upper computer, and the optical module is fixed in the cage of the upper computer by a clamping component of the unlocking component; by pulling the unlocking component, the clamping component of the unlocking component moves along with the unlocking component, so that the connection relation between the clamping component and the upper computer is changed, the clamping relation between the optical module and the upper computer is released, and the optical module can be drawn out from the cage of the upper computer.

The circuit board 300 is provided with circuit traces, electronic components (such as capacitors, resistors, triodes, and MOS transistors), and chips (such as an MCU, a laser driver chip, a limiting amplifier chip, a clock data recovery CDR, a power management chip, and a data processing chip DSP).

The circuit board connects the electrical appliances in the optical module together according to the circuit design through circuit wiring to realize the functions of power supply, electrical signal transmission, grounding and the like.

The chip on the circuit board 300 may be a multifunctional integrated chip, for example, a laser driver chip and an MCU chip are integrated into one chip, or a laser driver chip, a limiting amplifier chip and an MCU chip are integrated into one chip, and the chip is an integrated circuit, but the functions of the circuits do not disappear due to the integration, and only the circuit appears and changes, and the chip still has the circuit form. Therefore, when the circuit board is provided with three independent chips, namely, the MCU, the laser driver chip and the limiting amplifier chip, the scheme is equivalent to that when the circuit board 300 is provided with a single chip with three functions in one.

The circuit board is generally a hard circuit board, and the hard circuit board can also realize a bearing effect due to the relatively hard material of the hard circuit board, for example, the hard circuit board can stably bear a chip; when the optical transceiver is positioned on the circuit board, the rigid circuit board can also provide stable bearing; the hard circuit board can also be inserted into an electric connector in the upper computer cage, and specifically, a metal pin/golden finger is formed on the surface of the tail end of one side of the hard circuit board and is used for being connected with the electric connector; these are not easily implemented with flexible circuit boards.

A flexible circuit board is also used in a part of the optical module to supplement a rigid circuit board; the flexible circuit board is generally used in combination with a rigid circuit board, for example, the rigid circuit board may be connected to the optical transceiver device through the flexible circuit board.

The optical transceiver comprises two parts, namely an optical transmitting part and an optical receiving part, which are respectively used for realizing the transmission of optical signals and the reception of the optical signals. The light emitting part and the light receiving part may be combined together or may be independent of each other. The light emitting component and the light receiving component provided by the embodiment of the application are combined together to form a light receiving and transmitting integrated structure.

In order to realize the photoelectric conversion of the optical module, the silicon optical chip 400 is arranged on the circuit board 300, the silicon optical chip 400 can simultaneously modulate the emergent light generated by the light source 600 according to the power supply circuit and the signal circuit of the circuit board 300 into an emergent light signal meeting the requirement, and transmit the emergent light signal to the optical fiber connector 700, and modulate the optical signal from the optical fiber connector 700 into an electrical signal, and transmit the electrical signal to the circuit board 300, so that the optical fiber connector can be used as an optical transceiver integrated component, and realize the conversion of the photoelectric signal.

One end of the silicon optical chip 400 is connected to the signal circuit of the circuit board 300, and the other end of the silicon optical chip 400 is connected to the optical fiber connector 700 through the optical fiber ribbon 500. In performing the optical-to-electrical conversion, the silicon optical chip 400 is used to transmit optical signals through the optical fiber ribbon 500 and the optical fiber connector 700 and receive optical signals from the optical fiber connector 700 through the optical fiber ribbon 500.

One end of the optical fiber ribbon 500 is coupled to the silicon optical chip 400, and the other end of the optical fiber ribbon 500 is connected to the optical fiber connector 700, so as to receive and transmit optical signals. For this purpose, the optical fiber ribbon 500 may include two groups of optical fibers, i.e., a first optical fiber and a second optical fiber, the first optical fiber is used to transmit the optical signal modulated by the silicon optical chip 400 to the optical fiber connector 700, the second optical fiber is used to transmit the optical signal from the optical fiber connector 700 to the silicon optical chip 400, and the optical signal is modulated to form an electrical signal and then transmitted to the circuit board 300.

Fig. 5 is a schematic view illustrating assembly of a circuit board, a silicon optical chip, an optical fiber ribbon, a light source, and an optical interface in an optical module according to an embodiment of the present disclosure, fig. 6 is a schematic view illustrating assembly of another angle of the circuit board, the silicon optical chip, the optical fiber ribbon, the light source, and the optical interface in the optical module according to the embodiment of the present disclosure, and fig. 7 is a schematic view illustrating assembly of the silicon optical chip, the optical fiber ribbon, the light source, and the optical interface in the optical module according to the embodiment of the present disclosure. As shown in fig. 5, 6, and 7, fiber optic ribbon 500 includes: the optical fiber comprises a first optical fiber 510 and a second optical fiber 520 which are arranged in parallel, one end of the first optical fiber 510 is coupled with the light outlet of the silicon optical chip 400, the other end of the first optical fiber 510 is connected with the optical interface 710, and the first optical fiber 510 is used for receiving an emergent light signal modulated by the silicon optical chip 400 and transmitting the emergent light signal to the optical interface 710 so as to realize light emission. One end of the second optical fiber 520 is coupled to the light inlet of the silicon optical chip 400, the other end of the second optical fiber 520 is connected to the optical interface 710, the second optical fiber 520 is configured to receive a light receiving signal sent by the optical interface 710, and the light receiving signal is modulated by the silicon optical chip 400 to obtain an electrical signal and sent to the circuit board 300, so as to implement light reception.

The silicon optical chip 400 is used for realizing optical modulation, so that the power of an optical signal meets the use requirement of an optical module, but because the silicon optical chip 400 cannot emit light, an external light source is required to realize the emission of the optical signal in the light emission process. For this reason, the optical module provided in this embodiment further includes a light source 600, and the light source 600 may be disposed on the circuit board 300, connected to the power supply circuit of the circuit board 300, and configured to generate a light beam; the light source 600 may not be disposed on the circuit board 300, and is connected to the power supply circuit of the circuit board 300 by gold wires for generating light beams. The light source 600 is connected with the silicon optical chip 400 through the third optical fiber 530, one end of the third optical fiber 530 is coupled with the silicon optical chip 400, the other end of the third optical fiber 530 is connected with the light source 600, and emergent light generated by the light source 600 enters the silicon optical chip 400 through the third optical fiber 530.

The light source 600 is internally packaged with a laser chip, in the light emission process, the circuit board 300 supplies power to the light source 600 to drive the light source 600 to generate emergent light, the silicon optical chip 400 receives the emergent light generated by the light source 600 through the third optical fiber 530, and modulates the emergent light to obtain an emergent light signal, so that the optical power of the emergent light signal meets the optical requirement of the optical module, and the modulated optical signal is transmitted to the optical interface 710 through the first optical fiber 510.

The number of the laser chips arranged in the light source 600 may be multiple, the specific arrangement number may be determined according to the use requirement of the optical module, that is, the arrangement of the light path of the modulated light of the silicon optical chip 400 is performed, if the silicon optical chip 400 can realize the modulation of three paths of incident light and four paths of emergent light, three laser chips are required to be arranged, and the light emitted by each laser chip enters the corresponding light input waveguide in the silicon optical chip 400.

However, when the light beam generated by the light source 600 is transmitted to the silicon optical chip 400 through the third optical fiber 530, the light beam is easily reflected at the coupling end surface of the third optical fiber 530 and the silicon optical chip 400, so that part of the reflected light signal re-enters the light source 600 through the third optical fiber 530, and the light return loss is caused. In addition, when the optical signal modulated by the silicon optical chip 400 is transmitted to the optical interface 710 through the first optical fiber 510, since a gap exists between the light-emitting surface of the silicon optical chip 400 and the optical fiber end surface of the first optical fiber 510, when the optical signal is emitted from the light-emitting surface and transmitted to the optical fiber end surface of the first optical fiber 510, because the medium changes, the optical signal is easily reflected when being emitted to the optical fiber end surface of the first optical fiber 510, so that part of the reflected optical signal enters the silicon optical chip 400 again, and the optical return loss is caused; a gap also exists between the light emitting surface of the first optical fiber 510 and the light incident end surface of the optical interface 710, and when an optical signal is incident from the first optical fiber 510 to the interface end surface of the optical interface 710, because the medium changes, the optical signal is easily reflected when being incident to the interface end surface of the optical interface 710, so that part of the reflected optical signal enters the first optical fiber 510 again, and the optical return loss is caused. In addition, when the optical signal received by the optical interface 710 is transmitted to the silicon optical chip 400 through the second optical fiber 520, since a gap exists between the light-emitting end surface of the optical interface 710 and the light-in surface of the second optical fiber 520, when the optical interface 710 receives the optical signal and the light-in surface of the second optical fiber 520 is incident from the light-emitting end surface, the optical signal is easily reflected at the light-in surface of the second optical fiber 520 due to the change of the medium, so that part of the reflected optical signal enters the optical interface 710 again, and the return loss of light is caused; a gap is also formed between the light emitting surface of the second optical fiber 520 and the light incident surface of the silicon optical chip 400, and when an optical signal is input into the light incident surface of the silicon optical chip 400 through the second optical fiber 520, the optical signal is easily reflected at the light incident surface of the silicon optical chip 400 due to the change of a medium, so that part of the reflected optical signal enters the second optical fiber 520 again, and the optical return loss is caused.

In the existing optical module, when the return loss index test of the optical module does not meet the requirement, an optical isolator is usually used inside the optical source 600 to isolate the optical signal reflected back to the optical source 600 through the third optical fiber 530, so that the return loss index can be partially improved. However, there is no good way to improve the optical return loss at the coupling joint of the first optical fiber 510 and the optical interface 710, and the optical return loss at the coupling joint of the second optical fiber 520 and the silicon optical chip 400.

Fig. 8 is a schematic cross-sectional structure diagram of a silicon optical chip in an optical module according to an embodiment of the present disclosure, and fig. 9 is a schematic coupling diagram of a silicon optical circuit chip and a first optical fiber in an optical module according to an embodiment of the present disclosure. As shown in fig. 8 and 9, the silicon optical chip 400 provided in the embodiment of the present application includes a cover plate 410, a substrate 420, and a silicon optical circuit chip 430, where the silicon optical circuit chip 430 is disposed on the substrate 420, and the silicon optical circuit chip 430 is supported and fixed by the substrate 420; the cover plate 410 covers the substrate 420, so that the silicon optical circuit chip 430 is disposed in the accommodating cavity formed by the cover plate 410 and the substrate 420.

In the embodiment of the present application, the cover plate 410 and the end of the substrate 420 facing the optical fiber ribbon 500 are both provided with an opening, an optical inlet and an optical outlet are disposed in the opening, one end of the first optical fiber 510 is coupled to the silicon optical circuit chip 430 through the optical outlet, so that the optical signal modulated by the silicon optical circuit chip 430 is transmitted to the optical interface 710 through the optical outlet and the first optical fiber 510; one end of the second optical fiber 520 is coupled to the silicon optical circuit chip 430 through the light inlet, so that the optical electrical signal received by the optical interface 710 is transmitted into the silicon optical circuit chip 430 through the second optical fiber 520 and the light inlet to perform photoelectric conversion.

In order to facilitate the coupling connection between the silicon optical chip 400 and the optical fiber ribbon 500, an optical fiber bracket 540 is disposed at an end of the optical fiber ribbon 500 facing the silicon optical chip 400, and an end of the optical fiber bracket 540 facing the silicon optical chip 400 is fixedly bonded to the silicon optical circuit chip 430 by optical glue. Specifically, the silicon optical chip 400 further includes a connector 440, one end of the connector 440 is fixedly connected to the upper end surface of the silicon optical circuit chip 430, and the other end of the connector 440 extends out of the silicon optical chip 400 and is fixedly connected to the upper end surface of the optical fiber holder 540, so that the optical fiber holder 540 is hung near the light emitting surface of the silicon optical circuit chip 430 through the connector 440, and the light emitting surface/light incident surface of the silicon optical circuit chip 430 and the optical fiber in the optical fiber holder 540 are correspondingly mounted. When the fiber holder 540 is mounted on the connector 440, a predetermined distance exists between the end face of the optical fiber in the fiber holder 540 and the light emitting/incident surface of the silicon optical circuit chip 430, so as to ensure the coupling connection between the silicon optical circuit chip 430 and the optical fiber.

The optical fiber holder 540 is provided with a through hole, the end face of one end of the through hole faces the silicon optical chip 400, the end face of the other end of the through hole faces away from the silicon optical chip 400, so that the first optical fiber 510 and the second optical fiber 520 are inserted into the through hole, so that the first optical fiber 510 is inserted into the optical fiber holder 540 and coupled with the light outlet of the silicon optical chip 400, and the second optical fiber 520 is inserted into the optical fiber holder 540 and coupled with the light inlet of the silicon optical chip 400.

Fig. 10 is a side view of coupling between a silicon optical circuit chip and a first optical fiber in an optical module according to an embodiment of the present application. As shown in fig. 10, the silicon optical circuit chip 430 includes a silicon dioxide layer 4310 and a silicon base layer 4320, the silicon dioxide layer 4310 is disposed on the silicon base layer 4320, a light output waveguide 4330 is disposed in the silicon dioxide layer 4310, and a light-emitting surface 4340 of the light output waveguide 4330 facing the first optical fiber 510 is flush with a first end surface of the silicon dioxide layer 4310 facing the first optical fiber 510, so as to conveniently emit the signal light emitted from the light output waveguide 4330 into the first optical fiber 510.

The first optical fiber 510 includes a fiber core 5110, a cladding 5120, and a cladding cover 5130, wherein the cladding 5120 is wrapped on the outer side of the fiber core 5110, the cladding cover 5130 is wrapped on the outer side of the cladding 5120, and the fiber core 5110 and the light-emitting surface 4340 of the light output waveguide 4330 are disposed correspondingly. In the embodiment of the present application, the fiber end face 5140 of the first optical fiber 510 is the fiber end face of the core 5110.

Fig. 11 is a first schematic diagram of an optical transmission path between a silicon optical circuit chip and a first optical fiber in an optical module according to an embodiment of the present disclosure. As shown in fig. 11, the lengths of the silicon dioxide layer 4310 and the silicon base layer 4320 in the left-right direction may be the same, that is, the first end face of the silicon dioxide layer 4310 facing the first optical fiber 510 is flush with the end face of the silicon base layer 4320 facing the first optical fiber 510, and has the same distance with the end face of the first optical fiber 510. If the light-emitting surface 4340 of the light output waveguide 4330 in the silica layer 4310 is parallel to the fiber end face 5140 of the first optical fiber 510, and the light-emitting surface 4340 of the light output waveguide 4330 and the fiber end face 5140 of the first optical fiber 510 are both vertical surfaces (perpendicular to the circuit board 300) or inclined surfaces parallel to each other, the signal light emitted from the light-emitting surface 4340 of the light output waveguide 4330 is perpendicularly incident on the fiber end face 5140 of the first optical fiber 510, and since there is a gap between the light-emitting surface 4340 of the light output waveguide 4330 and the fiber end face 5140 of the first optical fiber 510, when the signal light is emitted from the light-emitting surface 4340 to the fiber end face 5140, the medium changes, the signal light is easily reflected at the fiber end face 5140, that is, the signal light which is perpendicularly incident is reflected at the fiber end face 5140, and the reflected signal light returns to the light output waveguide 4330 along the original path, thereby causing light return loss.

Fig. 12 is a second schematic diagram of an optical transmission path between a silicon optical circuit chip and a first optical fiber in an optical module according to an embodiment of the present application. As shown in fig. 12, the lengths of the silica layer 4310 and the silica layer 4320 in the left-right direction may also be different, that is, the first end face of the silica layer 4310 facing the first optical fiber 510 and the end face of the silica layer 4320 facing the first optical fiber 510 are not flush, the distance between the first end face of the silica optical circuit chip 430 and the optical fiber end face 5140 of the first optical fiber 510 is greater than the distance between the end face of the silica layer 4320 and the optical fiber end face 5140 of the first optical fiber 510, the portion of the silica layer 4320 protruding from the silica layer 4310 is provided with a second end face 4350, the second end face 4350 is connected to the first end face, and the second end face 4350 is provided with a reflective surface, because there is a gap between the light-emitting face 4340 of the optical output waveguide 4330 and the optical fiber end face 5140 of the first optical fiber 510, when the signal light is emitted from the light-emitting face 4340 to the optical fiber end face 5140, the dielectric changes, and the signal light is easily reflected at the optical fiber end face 5140, that is the optical output waveguide 4330 outputs the signal light-emitting face 4340, the signal light is reflected when being transmitted to the second end face 4350, the reflected signal light is transmitted to the optical fiber end face 5140 of the first optical fiber 510, and the reflected signal light may enter the first optical fiber 510 through the optical fiber end face 5140, which may cause optical return loss.

Fig. 13 is a side view of a new silicon optical circuit chip in an optical module according to an embodiment of the present disclosure, and fig. 14 is a first schematic diagram of an optical transmission path between the new silicon optical circuit chip and a first optical fiber in the optical module according to the embodiment of the present disclosure. As shown in fig. 13 and 14, in the embodiment of the present application, in order to prevent the signal light emitted from the optical output waveguide 4330 from being reflected at the fiber end face 5140 of the first optical fiber 510, and the reflected signal light is re-emitted into the optical output waveguide 4330, the light-emitting face 4340 of the optical output waveguide 4330 in the silicon optical circuit chip 430 may be arranged as an inclined plane, and the fiber end face 5140 of the first optical fiber 510 is still a vertical plane. The inclined plane is inclined away from the first optical fiber 510, i.e., inclined from the upper left to the lower right, so that the light-emitting surface 4340 and the optical fiber end face 5140 of the first optical fiber 510 form a certain angle α, such that the signal light output by the light-output waveguide 4330 cannot vertically irradiate the optical fiber end face 5140 of the first optical fiber 510, the signal light emitted from the light-emitting surface 4340 is firstly transmitted to the second end face 4350 and reflected at the second end face 4350, the reflected signal light is transmitted to the optical fiber end face 5140 of the first optical fiber 510, a part of the reflected signal light enters the first optical fiber 510 through the optical fiber end face 5140, and a part of the reflected signal light is reflected again at the optical fiber end face 5140.

Because the light-emitting surface 4340 of the light-output waveguide 4330 is an inclined surface, the light-emitting angle of the signal light emitted from the light-output waveguide 4330 is increased, after the light-emitting angle is increased and reflected by the second end surface 4350, the incident angle of the signal light reflected to the optical fiber end surface 5140 is larger, after the signal light with a larger incident angle is reflected again by the optical fiber end surface 5140, the emergent angle of the signal light reflected again is larger, so that the signal light reflected again can be ensured not to re-enter the light-output waveguide 4330, and the light return loss of the coupling surface of the silicon optical chip 400 and the first optical fiber 510 can be reduced.

In the embodiment of the present application, in order to ensure that the signal light emitted from the light output waveguide 4330 cannot enter the light output waveguide 4330 after being reflected by the second end face 4350 and reflected again by the optical fiber end face 5140, an angle α between the light-emitting face 4340 of the light output waveguide 4330 and the optical fiber end face 5140 of the first optical fiber 510 is 8 to 11 °.

Further, in addition to the light-emitting surface 4340 of the light-output waveguide 4330 being set as an inclined surface and the fiber end face 5140 of the first optical fiber 510 being set as a vertical surface to reduce the optical return loss at the optical interface of the silicon optical chip 400, the light-emitting surface 4340 of the light-output waveguide 4330 may also be set as a vertical surface and the fiber end face 5140 of the first optical fiber 510 being set as an inclined surface to reduce the optical return loss at the optical interface of the silicon optical chip 400.

Fig. 15 is a schematic partial structure diagram of a first optical fiber in an optical module according to an embodiment of the present disclosure, and fig. 16 is a second schematic optical transmission path diagram of a silicon optical circuit chip and the first optical fiber in the optical module according to the embodiment of the present disclosure. As shown in fig. 15 and 16, in order to avoid the signal light emitted from the optical output waveguide 4330 being reflected at the fiber end face 5140 of the first optical fiber 510, the reflected signal light is re-emitted into the optical output waveguide 4330, the fiber end face 5140 of the first optical fiber 510 may be an inclined plane, and the light-emitting face 4340 of the optical output waveguide 4330 in the silicon optical circuit chip 430 may be a vertical plane. The inclined surface of the optical fiber end face 5140 is inclined toward the silicon optical circuit chip 430, that is, inclined from the upper left to the lower right, so that the optical fiber end face 5140 and the light-emitting surface 4340 form a certain angle β, such that the signal light output by the optical output waveguide 4330 is transmitted to the second end face 4350 and reflected at the second end face 4350, the reflected signal light is transmitted to the optical fiber end face 5140 of the first optical fiber 510, a part of the reflected signal light enters the first optical fiber 510 via the optical fiber end face 5140, and a part of the reflected signal light is reflected at the optical fiber end face 5140 again.

Because the fiber end face 5140 of the first optical fiber 510 is an inclined plane, the incident angle of the signal light entering the fiber end face 5140 is increased, so that the exit angle of the signal light reflected again at the fiber end face 5140 is also increased, the signal light reflected again is reflected at the fiber end face 5140 at a larger angle, the reflected signal light does not enter the light output waveguide 4330, and the light return loss of the coupling surface of the silicon optical chip 400 and the first optical fiber 510 can be reduced.

In the embodiment of the present application, in order to ensure that the signal light emitted from the optical output waveguide 4330 cannot enter the optical output waveguide 4330 after being reflected by the second end face 4350 and reflected again by the optical fiber end face 5140, an angle β between the optical fiber end face 5140 of the first optical fiber 510 and the light-emitting face 4340 of the optical output waveguide 4330 is 6 to 9 °.

Further, in addition to the light-emitting surface 4340 of the light-output waveguide 4330 being set as a vertical surface and the fiber end face 5140 of the first optical fiber 510 being set as an inclined surface to reduce the optical return loss at the optical interface of the silicon optical chip 400, the light-emitting surface 4340 of the light-output waveguide 4330 and the fiber end face 5140 of the first optical fiber 510 may be set as inclined surfaces to reduce the optical return loss at the optical interface of the silicon optical chip 400.

Fig. 17 is a third schematic diagram of an optical transmission path between a silicon optical circuit chip and a first optical fiber in an optical module according to an embodiment of the present application. As shown in fig. 17, in order to avoid the signal light emitted from the optical output waveguide 4330 being reflected at the fiber end face 5140 of the first optical fiber 510, the reflected signal light is re-emitted into the optical output waveguide 4330, the light-emitting face 4340 of the optical output waveguide 4330 in the silicon optical circuit chip 430 may be set to be an inclined plane, the fiber end face 5140 of the first optical fiber 510 is also set to be an inclined plane, but the inclined plane of the light-emitting face 4340 is not parallel to the inclined plane of the fiber end face 5140. The light-emitting surface 4340 is inclined away from the first optical fiber 510, i.e. from the upper left to the lower right, such that the light-emitting surface 4340 and the silicon substrate 4320 form an angle α towards the third end surface 4360 of the first optical fiber 510; the inclined surface of the optical fiber end face 5140 is inclined towards the silicon optical circuit chip 430, that is, from the upper left to the lower right, so that the optical fiber end face 5140 and the silicon base layer 4320 form a certain angle β towards the third end face 4360 of the first optical fiber 510, such that the signal light output by the optical output waveguide 4330 is transmitted to the second end face 4350 and reflected at the second end face 4350, the reflected signal light is transmitted to the optical fiber end face 5140 of the first optical fiber 510, a part of the reflected signal light enters the first optical fiber 510 via the optical fiber end face 5140, and a part of the reflected signal light is reflected again at the optical fiber end face 5140.

Because the light-emitting surface 4340 of the light output waveguide 4330 is an inclined surface, the light-emitting angle of the signal light emitted by the light output waveguide 4330 is increased, after the light-emitting angle is increased and reflected by the second end surface 4350, the incident angle of the signal light reflected to the optical fiber end surface 5140 is larger, and after the signal light with a larger incident angle is reflected again by the optical fiber end surface 5140, the emergent angle of the signal light reflected again is larger; in addition, since the fiber end face 5140 of the first optical fiber 510 is an inclined surface, the incident angle of the signal light incident on the fiber end face 5140 is increased, and the exit angle of the signal light reflected again at the fiber end face 5140 is also increased, so that the signal light reflected again is reflected at the fiber end face 5140 at a large angle. Therefore, the re-reflected signal light is prevented from re-entering the light output waveguide 4330, and the light return loss of the coupling surface of the silicon optical chip 400 and the first optical fiber 510 can be reduced.

In the embodiment of the present application, in order to ensure that the signal light emitted from the optical output waveguide 4330 cannot enter the optical output waveguide 4330 after being reflected by the second end face 4350 and reflected again by the optical fiber end face 5140, an angle α between the light-emitting face 4340 of the optical output waveguide 4330 and the third end face 4360 of the silicon-based layer 4320 is 8 to 11 °, and an angle β between the optical fiber end face 5140 of the first optical fiber 510 and the third end face 4360 of the silicon-based layer 4320 is 6 to 9 °.

Further, in addition to the light exit surface 4340 of the light output waveguide 4330 and the fiber end face 5140 of the first optical fiber 510 are both disposed as inclined surfaces to reduce the optical return loss at the optical interface of the silicon optical chip 400, in the present application, the light exit surface 4340 of the light output waveguide 4330 and the fiber end face 5140 of the first optical fiber 510 are both disposed as vertical surfaces, and an antireflection film is disposed on a side of the fiber end face 5140 facing the silicon optical chip 400 to absorb the signal light reflected again at the fiber end face 5140 through the antireflection film, so as to reduce the optical return loss at the optical interface of the silicon optical chip 400.

Fig. 18 is a fourth schematic view of an optical transmission path between a silicon optical circuit chip and a first optical fiber in an optical module according to an embodiment of the present application. As shown in fig. 18, in order to prevent the signal light emitted from the light output waveguide 4330 from being reflected at the fiber end face 5140 of the first optical fiber 510, the reflected signal light is re-emitted into the light output waveguide 4330, the light emitting face 4340 of the light output waveguide 4330 may be set to be a vertical plane, the fiber end face 5140 of the first optical fiber 510 may be set to be a vertical plane, and a first metal antireflection film 5150 may be disposed on the side of the fiber end face 5140 facing the silicon optical chip 400, and the antireflection film is adhered to the side of the fiber end face 5140 facing the silicon optical chip 400.

Thus, when the signal light output from the light-emitting surface 4340 of the light output waveguide 4330 perpendicularly enters the fiber end face 5140 of the first optical fiber 510, the perpendicularly-entering signal light directly passes through the first metal antireflection film 5150 and is input into the first optical fiber 510 without being reflected at the fiber end face 5140, and the reflected light is not emitted into the light output waveguide 4330; or, the signal light emitted from the light-emitting surface 4340 of the light output waveguide 4330 is transmitted to the second end surface 4350 and reflected at the second end surface 4350, and the reflected signal light is transmitted to the fiber end surface 5140 of the first optical fiber 510, because the first metal antireflection film 5150 is disposed on one side of the fiber end surface 5140, and the signal light reflected by the second end surface 4350 is transmitted to the fiber end surface 5140, the signal light directly enters the first optical fiber 510 through the first metal antireflection film 5150 and the fiber end surface 5140, and is not reflected again at the fiber end surface 5140, so that the signal light reflected again does not enter the light output waveguide 4330, and the light return loss of the coupling surface between the silicon optical chip 400 and the first optical fiber 510 can be reduced.

In the embodiment of the present application, in order to ensure that the signal light emitted from the light output waveguide 4330 directly enters the fiber core 5110 of the first optical fiber 510 via the first metal antireflection film 5150 and the fiber end face 5140, and at the same time, the side face of the first metal antireflection film 5150 cannot contact with the third end face 4360 of the silicon optical circuit chip 430, the thickness of the first metal antireflection film 5150 is 5 to 20 μm.

When the first metal antireflection film 5150 is arranged on one side of the fiber end face 5140, a layer of the first metal antireflection film 5150 can be directly plated on one side of the fiber end face 5140 facing the silicon optical chip 400, and the plating thickness of the first metal antireflection film 5150 is a preset thickness, so that the antireflection property of the fiber end face 5140 is increased, and the signal light directly penetrates through the fiber end face 5140 and enters the first optical fiber 510; or a first metal antireflection film 5150 with a preset thickness may be processed, and then one side of the first metal antireflection film 5150 is bonded to one side of the optical fiber end face 5140 by glue, so that the signal light directly penetrates through the optical fiber end face 5140 and enters the first optical fiber 510.

Furthermore, in addition to the light exit surface 4340 of the light output waveguide 4330 and the fiber end surface 5140 of the first optical fiber 510 being both vertical surfaces, and an antireflection film being disposed on the side of the fiber end surface 5140 facing the silicon optical chip 400 to prevent the signal light from being reflected again on the fiber end surface 5140, thereby reducing the light return loss at the optical interface of the silicon optical chip 400, the light exit surface 4340 of the light output waveguide 4330 may also be vertical surfaces, the fiber end surface 5140 of the first optical fiber 510 being an inclined surface, and an antireflection film being disposed on the inclined surface of the fiber end surface 5140 to prevent the signal light from being reflected again on the fiber end surface 5140, thereby reducing the light return loss at the optical interface of the silicon optical chip 400.

Fig. 19 is a fifth schematic view of an optical transmission path between a silicon optical circuit chip and a first optical fiber in an optical module according to an embodiment of the present application. As shown in fig. 19, in order to avoid the signal light emitted from the light output waveguide 4330 being reflected at the fiber end face 5140 of the first optical fiber 510, the reflected signal light is re-emitted into the light output waveguide 4330, the light emitting face 4340 of the light output waveguide 4330 may be set to be a vertical face, the fiber end face 5140 of the first optical fiber 510 is set to be an inclined face, and a second metal antireflection film 5160 is disposed on a side of the inclined face facing the silicon optical chip 400. The inclined surface of the optical fiber end face 5140 is inclined toward the silicon optical circuit chip 430, i.e., from the upper left to the lower right, so that the optical fiber end face 5140 and the light-emitting surface 4340 of the optical output waveguide 4330 form a certain angle δ, and thus the signal light output by the optical output waveguide 4330 is transmitted to the second end face 4350 and reflected at the second end face 4350, and the reflected signal light is transmitted to the optical fiber end face 5140 of the first optical fiber 510.

Because the fiber end face 5140 of the first optical fiber 510 is an inclined plane, the incident angle of the signal light entering the fiber end face 5140 is increased, so that the exit angle of the signal light reflected again at the fiber end face 5140 is also increased, the signal light reflected again is reflected at the fiber end face 5140 at a larger angle, the reflected signal light does not enter the light output waveguide 4330, and the light return loss of the coupling surface of the silicon optical chip 400 and the first optical fiber 510 can be reduced.

In addition, since the second metal antireflection film 5160 is disposed on the side of the optical fiber end face 5140 facing the silicon optical chip 400, after the signal light reflected by the second end face 4350 is transmitted to the optical fiber end face 5140, the signal light directly enters the first optical fiber 510 through the second metal antireflection film 5160 and the optical fiber end face 5140 without being reflected again at the optical fiber end face 5140, and the signal light reflected again does not enter the light output waveguide 4330, so that the light return loss of the coupling surface between the silicon optical chip 400 and the first optical fiber 510 can be further reduced.

In the embodiment of the present application, in order to ensure that the signal light emitted from the optical output waveguide 4330 cannot enter the optical output waveguide 4330 after being reflected by the second end face 4350 and reflected again by the optical fiber end face 5140, an angle δ between the optical fiber end face 5140 of the first optical fiber 510 and the light-emitting face 4340 of the optical output waveguide 4330 is 6 to 9 °. Meanwhile, in order to prevent the side surface of the second metal antireflection film 5160 from contacting the third end surface 4360 of the silicon optical circuit chip 430, the thickness of the second metal antireflection film 5160 is 5 to 20 micrometers.

When the second metal antireflection film 5160 is disposed on one side of the fiber end face 5140, a second metal antireflection film 5160 may be directly plated on the inclined surface of the fiber end face 5140 facing the silicon optical chip 400, and the plating thickness of the second metal antireflection film 5160 is a predetermined thickness, so as to increase the antireflection property of the fiber end face 5140, and enable the signal light to directly penetrate through the fiber end face 5140 and enter the first optical fiber 510; or a second metal antireflection film 5160 with a preset thickness may be processed, and then one side of the second metal antireflection film 5160 is bonded to one side of the optical fiber end face 5140 by glue, so that the signal light directly penetrates through the optical fiber end face 5140 and enters the first optical fiber 510.

Fig. 20 is a schematic diagram of an optical transmission path between a silicon optical circuit chip and a second optical fiber in an optical module according to an embodiment of the present disclosure. As shown in fig. 20, in the optical module according to the embodiment of the present invention, optical return loss is likely to occur not only at the coupling end surface between the silicon microchip 400 and the first optical fiber 510 but also at the coupling end surface between the silicon microchip 400 and the second optical fiber 520. When the light inlet of the silicon optical chip 400 is coupled to the second optical fiber 520, the signal light received by the optical interface 710 is transmitted in the second optical fiber 520, and the signal light is transmitted to the position of the second optical fiber 520 close to the optical fiber end surface 5240 of the silicon optical chip 400, because a gap exists between the optical fiber end surface 5240 of the second optical fiber 520 and the light inlet of the silicon optical chip 400, when the signal light is emitted from the optical fiber end surface 5240 to the light inlet of the silicon optical chip 400, the signal light may be vertically incident on the light inlet surface 4380 of the light input waveguide 4370 in the silicon optical chip 400, and due to a change in a medium, the signal light is easily reflected when the light inlet surface 4380 is arranged, so that the reflected signal light returns to the second optical fiber 520 along the original path, and the light return loss is caused.

To solve this problem, the present application can avoid the optical return loss at the coupling end face of the silicon optical chip 400 and the first optical fiber 510 by avoiding the optical return loss at the coupling end face of the silicon optical chip 400 and the second optical fiber 520, so as to improve the optical receiving performance of the second optical fiber 520 and the silicon optical chip 400.

The optical module provided by the embodiment of the application comprises a circuit board, a silicon optical chip, an optical fiber ribbon, a light source and an optical interface, wherein the silicon optical chip is arranged on the circuit board, and the light source is electrically connected with a power supply circuit of the circuit board to generate a light beam; the optical fiber ribbon comprises a first optical fiber, a second optical fiber and a third optical fiber, and light beams generated by the light source are transmitted to the silicon optical chip through the third optical fiber; the silicon optical chip modulates the light beam according to a power supply circuit and a signal circuit of the circuit board, and the modulated signal light is transmitted to the optical interface through the first optical fiber to realize the emission of the light; the signal light received by the optical interface is transmitted to the silicon optical chip through the second optical fiber, and the silicon optical chip converts the signal light into an electric signal to realize the light receiving. When the silicon optical chip is coupled with the first optical fiber, a gap exists between the light-emitting surface of the optical output waveguide in the silicon optical chip and the optical fiber end surface of the first optical fiber, when signal light is emitted from the light-emitting surface to the optical fiber end surface, the signal light is easy to reflect at the optical fiber end surface due to the change of a medium, and the reflected signal light enters the optical output waveguide to cause optical return loss. In order to reduce the optical return loss of the optical output interface of the silicon optical chip, the light-emitting surface of the optical output waveguide in the silicon optical chip is arranged into an inclined surface, the fiber end surface of the first optical fiber is arranged into a vertical surface, the light-emitting surface of the optical output waveguide is arranged into a vertical surface, the fiber end surface of the first optical fiber is arranged into an inclined surface, the light-emitting surface of the optical output waveguide and the fiber end surface of the first optical fiber are arranged into inclined surfaces, the first metal antireflection film is arranged on one side of the fiber end surface facing the silicon optical chip, the light-emitting surface of the optical output waveguide is arranged into a vertical surface, the fiber end surface of the first optical fiber is arranged into an inclined surface, the second metal antireflection film is arranged on one side of the inclined surface facing the silicon optical chip, and the like, so that the signal light reflected on the fiber end surface is prevented from reentering the optical output waveguide, and the optical return loss at the coupling joint of the silicon optical chip and the first optical fiber is effectively reduced, the light emission performance of the optical module is ensured.

Similarly, when the silicon optical chip is coupled with the second optical fiber, a gap exists between the light incident surface of the light input waveguide in the silicon optical chip and the optical fiber end surface of the second optical fiber, when the signal light is emitted from the optical fiber end surface of the second optical fiber to the light incident surface, the signal light is easily reflected at the light incident surface due to the change of the medium, and the reflected signal light enters the second optical fiber to cause light return loss. In order to reduce the optical return loss of the optical input interface of the silicon optical chip, the present application can avoid the optical return loss at the coupling end face of the silicon optical chip and the first optical fiber by adopting a method of avoiding the optical return loss at the coupling end face of the silicon optical chip and the first optical fiber, for example, the optical fiber end face of the second optical fiber is set to be an inclined plane, the light incident surface of the optical input waveguide is set to be a vertical plane, the optical fiber end face of the second optical fiber and the light incident surface of the optical input waveguide are set to be inclined planes, the optical fiber end face of the second optical fiber and the light incident surface of the optical input waveguide are both set to be vertical planes, a metal antireflection film is arranged on one side of the light incident surface facing the second optical fiber, the light incident surface of the optical input waveguide is set to be an inclined plane, the optical fiber end face of the second optical fiber is set to be a vertical plane, and a metal antireflection film is arranged on one side of the inclined plane facing the second optical fiber, so as to improve the light receiving performance of the optical module.

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

Claims (10)

1. A light module, comprising:

a circuit board;

a light source for generating a light beam;

the silicon optical chip is arranged on the circuit board and comprises an optical output waveguide; the light output waveguide is used for transmitting the signal light out;

the optical fiber ribbon comprises a first optical fiber, a second optical fiber and a third optical fiber, wherein one end of the first optical fiber is coupled with a light-emitting surface of the optical output waveguide, a gap is formed between the light-emitting surface of the optical output waveguide and the optical fiber end surface of the first optical fiber, an acute angle is formed between the light-emitting surface of the optical output waveguide and the optical fiber end surface of the first optical fiber, and an antireflection film is arranged on one side, facing the light-emitting surface, of the optical fiber end surface; one end of the second optical fiber is coupled with the light inlet of the silicon optical chip to realize the light receiving; the light source is connected with the silicon optical chip through the third optical fiber;

and the optical fiber connector is connected with the other end of the first optical fiber and the other end of the second optical fiber.

2. The optical module of claim 1, wherein a light-emitting surface of the light output waveguide is perpendicular to the circuit board, and the fiber end surface of the first optical fiber and the antireflection film form a first angle with the light-emitting surface.

3. The light module as claimed in claim 2, wherein the first angle is 8-11 °.

4. The optical module according to claim 1, wherein the antireflection film has a thickness of 5 to 20 μm.

5. The optical module according to claim 1, wherein the antireflection film is a metal antireflection film.

6. The optical module of claim 1, wherein the silicon photonic chip comprises a silicon photonic chip comprising a silicon dioxide layer and a silicon base layer, the silicon dioxide layer disposed on the silicon base layer, the optical output waveguide disposed within the silicon dioxide layer;

the distance between the silicon dioxide layer and the optical fiber end face is larger than the distance between the silicon substrate and the optical fiber end face, and the silicon substrate protrudes out of the second end face of the silicon dioxide layer and is provided with a reflecting layer.

7. The optical module according to claim 1, wherein the first optical fiber includes a core, a cladding layer surrounding the core, and a cover plate surrounding the cladding layer, and an optical fiber end surface of the core is disposed corresponding to the light exit surface of the light output waveguide.

8. The optical module of claim 7, wherein a diameter dimension of the antireflection film is consistent with a diameter dimension of the first optical fiber.

9. The optical module of claim 7, wherein the antireflection film has a diameter dimension larger than a diameter dimension of the core in the first optical fiber.

10. A light module, comprising:

a circuit board;

a light source for generating a light beam;

the silicon optical chip is arranged on the circuit board and comprises an optical input waveguide; for converting the optical signal into an electrical signal;

the optical fiber ribbon comprises a first optical fiber, a second optical fiber and a third optical fiber, wherein one end of the first optical fiber is coupled and connected with the light outlet of the silicon optical chip so as to realize light emission; one end of the second optical fiber is coupled with the light incident surface of the light input waveguide, a gap exists between the light incident surface of the light input waveguide and the optical fiber end surface of the second optical fiber, an acute angle is formed between the light incident surface of the light input waveguide and the optical fiber end surface of the second optical fiber, and an antireflection film is arranged on one side, facing the second optical fiber, of the light incident surface of the light input waveguide; the light source is connected with the silicon optical chip through the third optical fiber;

and the optical fiber connector is connected with the other end of the first optical fiber and the other end of the second optical fiber.

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