CN220493002U - Optical module - Google Patents

Abstract

The embodiment of the application discloses an optical module, including: and the circuit board is provided with a transmitting through hole, and the transmitting panel is positioned in the transmitting through hole. The light emitting chip is arranged above the emitting panel, and the difference between the thermal expansion coefficient of the emitting panel and the thermal expansion coefficient of the light emitting chip is smaller than the difference between the thermal expansion coefficient of the circuit board and the thermal expansion coefficient of the light emitting chip. Therefore, when the temperature rises or decreases, the difference of the thermal expansion or cold contraction of the emission panel and the light emission chip is smaller than that of the circuit board and the light emission chip, so that the stress effect on the light emission chip is effectively reduced, the error rate is reduced, and the reliability of the light module in a high-low temperature environment is improved.

Description

Optical module

Technical Field

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

Background

In a novel service mode and an application mode of cloud computing, mobile internet, video and the like, an optical communication technology can be used. In optical communication, an optical module is a tool for realizing mutual conversion of optical and electrical signals, and is one of key devices in optical communication equipment. With the rapid development of 5G networks, optical modules at the core position of optical communications have been developed.

The optical module deforms in a high-temperature or low-temperature environment, so that the error rate is increased.

Disclosure of Invention

The application provides an optical module, which is used for reducing the error rate of the optical module and improving the communication quality.

In order to solve the technical problems, the embodiment of the application discloses the following technical scheme:

in one aspect, an embodiment of the present application discloses an optical module, including:

a circuit board having an emission through hole;

a transmitting panel embedded inside the transmitting through hole;

a light emitting chip positioned on the surface of the emitting panel, wherein the light emitted by the light emitting chip is perpendicular to the circuit board,

the lens component is positioned above the circuit board, a light emitting chip is arranged below the lens component, and the lens component changes the propagation direction of light emitted by the light emitting chip;

wherein the difference between the thermal expansion coefficient of the emission panel and the thermal expansion coefficient of the light emission chip is smaller than the difference between the thermal expansion coefficient of the circuit board and the thermal expansion coefficient of the light emission chip.

On the other hand, the embodiment of the application discloses an optical module, which comprises:

the circuit board is provided with a blind emission hole;

a transmitting panel embedded inside the transmitting blind hole; the lower surface of the emission panel is connected with the bottom of the emission blind hole;

a light emitting chip located on a surface of the emission panel;

the lens component is positioned above the circuit board, a light emitting chip is arranged below the lens component, and the lens component changes the propagation direction of light emitted by the light emitting chip;

the difference between the thermal expansion coefficient of the emission panel and the thermal expansion coefficient of the light emission chip is smaller than the difference between the thermal expansion coefficient of the circuit board and the thermal expansion coefficient of the light emission chip;

the light emitting chip is a vertical cavity surface emitting laser, and the emission panel covers the projection of the light emitting chip.

Compared with the prior art, the beneficial effect of this application:

the embodiment of the application discloses an optical module, including: and the circuit board is provided with a transmitting through hole, and the transmitting panel is positioned in the transmitting through hole. The light emitting chip is arranged above the emitting panel, and the difference between the thermal expansion coefficient of the emitting panel and the thermal expansion coefficient of the light emitting chip is smaller than the difference between the thermal expansion coefficient of the circuit board and the thermal expansion coefficient of the light emitting chip. Therefore, when the temperature rises or decreases, the difference of the thermal expansion or cold contraction of the emission panel and the light emission chip is smaller than that of the circuit board and the light emission chip, so that the stress effect on the light emission chip is effectively reduced, the error rate is reduced, and the reliability of the light module in a high-low temperature environment is improved.

Drawings

In order to more clearly illustrate the technical solutions of the present disclosure, the drawings that need 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 may be obtained according to these drawings to those of ordinary skill in the art. Furthermore, the drawings in the following description may be regarded as schematic diagrams, not limiting the actual size of the products, the actual flow of the methods, the actual timing of the signals, etc. according to the embodiments of the present disclosure.

FIG. 1 is a partial architectural diagram of an optical communication system according to some embodiments;

FIG. 2 is a partial block diagram of a host computer according to some embodiments;

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

fig. 4 is an exploded view of a light module according to some embodiments;

FIG. 5 is a schematic diagram illustrating the assembly of a circuit board and a lens assembly in an optical module according to some embodiments of the present application;

FIG. 6 is an exploded schematic view of a circuit board and lens assembly in an optical module according to some embodiments of the present application;

FIG. 7 is a schematic diagram of a light emitting chip and a circuit board structure according to some embodiments of the present application;

FIG. 8 is a schematic diagram of a light emitting chip and a circuit board according to some embodiments of the present application;

FIG. 9 is a schematic diagram of a light emitting chip and a circuit board according to some embodiments of the present application;

FIG. 10 is a schematic cross-sectional view of a light emitting chip and a circuit board according to some embodiments of the present application;

FIG. 11 is a schematic diagram of a light receiving component and a circuit board structure according to some embodiments of the present application;

FIG. 12 is a schematic cross-sectional view of a light receiving unit and a circuit board according to some embodiments of the present application;

fig. 13 is an exploded view of a light receiving device and a circuit board according to some embodiments of the present application.

Detailed Description

The optical communication technology establishes information transfer between information processing apparatuses, and the optical communication technology loads information onto light, and uses propagation of light to realize information transfer, and the light loaded with information is an optical signal. The optical signal propagates in the information transmission device, so that the loss of optical power can be reduced, and the high-speed, long-distance and low-cost information transmission can be realized. Information that can be processed by the information processing device exists in the form of an electrical signal, and an optical network terminal/gateway, a router, a switch, a mobile phone, a computer, a server, a tablet computer and a television are common information processing devices, and an optical fiber and an optical waveguide are common information transmission devices.

The mutual conversion of optical signals and electric signals between the information processing equipment and the information transmission equipment is realized through an optical module. For example, an optical fiber is connected to an optical signal input end and/or an optical signal output end of the optical module, and an optical network terminal is connected to an electrical signal input end and/or an electrical signal output end of the optical module; the optical module converts the first optical signal into a first electric signal, and the optical module transmits the first electric signal into an optical network terminal; the second electrical signal from the optical network terminal is transmitted into the optical module, the optical module converts the second electrical signal into a second optical signal, and the optical module transmits the second optical signal into the optical fiber. Because the information processing devices can be connected with each other through an electrical signal network, at least one type of information processing device is required to be directly connected with the optical module, and not all types of information processing devices are required to be directly connected with the optical module, and the information processing device directly connected with the optical module is called an upper computer of the optical module.

Fig. 1 is a partial architectural diagram of an optical communication system according to some embodiments. As shown in fig. 1, a part of the optical communication system is represented as a remote information processing apparatus 1000, a local information processing apparatus 2000, a host computer 100, an optical module 200, an optical fiber 101, and a network cable 103.

One end of the optical fiber 101 extends toward the remote information processing apparatus 1000, and the other end is connected to the optical interface of the optical module 200. The optical signal can be totally reflected in the optical fiber 101, the propagation of the optical signal in the total reflection direction can almost maintain the original optical power, the optical signal can be totally reflected in the optical fiber 101 for a plurality of times, the optical signal from the direction of the far-end information processing device 1000 is transmitted into the optical module 200, or the light from the optical module 200 is propagated towards the direction of the far-end information processing device 1000, so that the information transmission with long distance and low power consumption is realized.

The number of the optical fibers 101 may be one or plural (two or more); the optical fiber 101 and the optical module 200 are movably connected in a pluggable mode, and can also be fixedly connected.

The upper computer 100 is provided with an optical module interface 102, and the optical module interface 102 is configured to be connected with the optical module 200, so that the upper computer 100 and the optical module 200 are connected by unidirectional/bidirectional electric signals; the upper computer 100 is configured to provide data signals to the optical module 200, or receive data signals from the optical module 200, or monitor and control the working state of the optical module 200.

The upper computer 100 has an external electrical interface, such as a universal serial bus interface (Universal Serial Bus, USB), a network cable interface 104, and the external electrical interface can access an electrical signal network. Illustratively, the network cable interface 104 is configured to access the network cable 103, thereby enabling the host computer 100 to establish a unidirectional/bidirectional electrical signal connection with the network cable 103.

Optical network terminals (ONU, optical Network Unit), optical line terminals (OLT, optical Line Terminal), optical network devices (ONT, optical Network Terminal), and data center servers are common upper computers.

One end of the network cable 103 is connected to the local information processing device 2000, the other end is connected to the host computer 100, and the network cable 103 establishes an electrical signal connection between the local information processing device 2000 and the host computer 100.

Illustratively, the third electrical signal sent by the local information processing apparatus 2000 is transmitted to the host computer 100 through the network cable 103, the host computer 100 generates a second electrical signal based on the third electrical signal, the second electrical signal from the host computer 100 is transmitted to the optical module 200, the optical module 200 converts the second electrical signal into a second optical signal, the optical module 200 transmits the second optical signal to the optical fiber 101, and the second optical signal is transmitted to the remote information processing apparatus 1000 in the optical fiber 101.

Illustratively, the first optical signal from the direction of the remote information processing apparatus 1000 propagates through the optical fiber 101, the first optical signal from the optical fiber 101 is transmitted into the optical module 200, the optical module 200 converts the first optical signal into a first electrical signal, the optical module 200 transmits the first electrical signal into the host computer 100, the host computer 100 generates a fourth electrical signal based on the first electrical signal, and the host computer 100 transmits the fourth electrical signal into the local information processing apparatus 2000.

The optical module is a tool for realizing the mutual conversion of the optical signal and the electric signal, and the information is not changed in the conversion process of the optical signal and the electric signal, and the encoding and decoding modes of the information can be changed.

Fig. 2 is a partial block diagram of a host computer according to some embodiments. In order to clearly show the connection relationship between the optical module 200 and the host computer 100, fig. 2 only shows the structure of the host computer 100 and the optical module 200. As shown in fig. 2, the upper computer 100 further includes a PCB circuit board 105 disposed in the housing, a cage 106 disposed on a surface of the PCB circuit board 105, a heat sink 107 disposed on the cage 106, and an electrical connector (not shown in the drawing) disposed inside the cage 106, wherein the heat sink 107 has a convex structure for increasing a heat dissipation area, and the fin-like structure is a common convex structure.

The optical module 200 is inserted into the cage 106 of the host computer 100, the optical module 200 is fixed by the cage 106, and heat generated by the optical module 200 is transferred to the cage 106 and then diffused through the heat sink 107. After the optical module 200 is inserted into the cage 106, the electrical interface of the optical module 200 is connected with an electrical connector inside the cage 106.

Fig. 3 is a block diagram of an optical module according to some embodiments, and fig. 4 is an exploded view of an optical module according to some embodiments. As shown in fig. 3 and 4, the optical module 200 includes a housing (shell), a circuit board 300 disposed within the housing, a light emitting part 400, and a light receiving part. The present disclosure is not limited thereto and in some embodiments, the optical module 200 includes one of a light emitting part 400 and a light receiving part.

The housing includes an upper housing 201 and a lower housing 202, the upper housing 201 being capped on the lower housing 202 to form the above-described housing having two openings 204 and 205; the outer contour of the housing generally presents a square shape.

In some embodiments, the lower housing 202 includes a bottom plate 2021 and two lower side plates 2022 disposed on both sides of the bottom plate 2021 and perpendicular to the bottom plate 2021; the upper housing 201 includes a cover 2011, and the cover 2011 is covered on two lower side plates 2022 of the lower housing 202 to form the housing.

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

The direction of the connection line of the two openings 204 and 205 may be identical to the length direction of the optical module 200 or not identical to the length direction of the optical module 200. For example, opening 204 is located at the end of light module 200 (right end of fig. 3) and opening 205 is also located at the end of light module 200 (left end of fig. 3). Alternatively, the opening 204 is located at the end of the light module 200, while the opening 205 is located at the side of the light module 200. The opening 204 is an electrical interface, and the golden finger of the circuit board 300 extends out of the electrical interface and is inserted into an electrical connector of the upper computer; the opening 205 is an optical port configured to access the optical fiber 101 such that the optical fiber 101 connects to the light emitting component 400 and/or the light receiving component in the optical module 200.

By adopting the assembly mode of combining the upper shell 201 and the lower shell 202, the circuit board 300, the light emitting component 400, the light receiving component and other components are convenient to be installed in the shells, and the shapes of the components can be packaged and protected by the upper shell 201 and the lower shell 202. In addition, when the circuit board 300, the light emitting part 400, the light receiving part, and the like are assembled, the positioning part, the heat radiating part, and the electromagnetic shielding part of these devices are easily disposed, which is advantageous for automatized production.

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

In some embodiments, the light module 200 further includes an unlocking member 600 located outside its housing. The unlocking part 600 is configured to achieve a fixed connection between the optical module 200 and the upper computer, or to release the fixed connection between the optical module 200 and the upper computer.

For example, the unlocking member 600 is located outside of the two lower side plates 2022 of the lower housing 202, and includes an engaging member that mates with the cage 106 of the upper computer. When the optical module 200 is inserted into the cage 106, the optical module 200 is fixed in the cage 106 by the engaging member of the unlocking member 600; when the unlocking member 600 is pulled, the engaging member of the unlocking member 600 moves along with the unlocking member, so that the connection relationship between the engaging member and the host computer is changed, and the engagement and fixed connection between the optical module 200 and the host computer is released, so that the optical module 200 can be pulled out from the cage 106.

The circuit board 300 includes circuit traces, electronic components, chips, etc., and the electronic components and the chips are connected together according to a circuit design through the circuit traces to realize functions of power supply, electric signal transmission, grounding, etc. The electronic components may include, for example, capacitors, resistors, transistors, metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET). The chips may include, for example, a micro control unit (Microcontroller Unit, MCU), a laser driver chip, a transimpedance amplifier (Transimpedance Amplifier, TIA), a limiting amplifier (limiting amplifier), a clock data recovery chip (Clock and Data Recovery, CDR), a power management chip, a digital signal processing (Digital Signal Processing, DSP) chip.

The circuit board 300 is generally a hard circuit board, and the hard circuit board can also realize a bearing function due to the relatively hard material, for example, the hard circuit board can stably bear the electronic components and chips; the hard circuit board is also convenient to insert into an electric connector in the host 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 independent leads. The circuit board 300 is inserted into the cage 106 and is electrically connected to the electrical connectors within the cage 106 by the gold fingers. The gold fingers may be disposed on only one surface (e.g., the upper surface shown in fig. 4) of the circuit board 300, or may be disposed on both upper and lower surfaces of the circuit board 300, so as to provide more pins. The golden finger is configured to establish electrical connection with the upper computer to achieve 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, and the flexible circuit board is generally used in cooperation with a hard circuit board to supplement the hard circuit board.

The light emitting part 400 and/or the light receiving part are located at a side of the circuit board 300 away from the gold finger; in some embodiments, the light emitting and receiving components 400 and 300, respectively, are physically separated from the circuit board 300 and then electrically connected to the circuit board 300 through corresponding flexible circuit boards or electrical connectors, respectively; in some embodiments, the light emitting and/or light receiving components may be disposed directly on the circuit board 300, may be disposed on a surface of the circuit board, or may be disposed on a side of the circuit board.

Fig. 5 is an assembly schematic diagram of a circuit board, a lens assembly, a fiber support and a fiber array in an optical module according to some embodiments of the present application, and fig. 6 is an exploded schematic diagram of a circuit board, a lens assembly in an optical module according to some embodiments of the present application. As shown in fig. 5 and 6, the lens assembly 410 provided in the present application is disposed on the circuit board 300, and is covered above the optical chip (the optical chip mainly refers to a chip related to a photoelectric conversion function, such as the optical emission chip 420, the driving chip 430, the optical receiving chip, the transimpedance amplifying chip, the limiting amplifying chip, etc.) on the circuit board 300 in a cover-fastening manner, the lens assembly 410 and the circuit board 300 form a cavity for wrapping the optical chip, such as the optical emission chip, and the lens assembly 410 and the circuit board 300 together form a structure for packaging the optical chip. Light emitted from the light emitting chip is reflected by the lens assembly 410 and enters the optical fiber array, light from the optical fiber array is reflected by the lens assembly 410 and enters the light receiving chip, and the lens assembly 410 establishes optical connection between the light emitting chip 420 and the optical fiber array. The lens assembly 410 not only serves to seal the optical chip, but also establishes an optical connection between the optical chip and the optical fiber array.

Fig. 7 is a schematic diagram of a light emitting chip and a circuit board structure according to some embodiments of the present application. As shown in fig. 7, the light emitting chip is located between the lens assembly 410 and the circuit board 300, and the light emitting chip 420 is connected to the circuit board. The top surface of the light emitting chip 420 emits light signals, which are converted in direction by the lens assembly 410, and then enter the optical fiber array. When the temperature of the optical module changes, the circuit board expands or contracts due to the temperature, and stress is generated on the light emitting chip in the length direction.

Fig. 8 is a schematic diagram illustrating stress generated by heating a light emitting chip and a circuit board according to some embodiments of the present application. As shown in fig. 8, when the optical module is heated and the temperature increases, the circuit board expands in the length direction (X direction in the drawing) so that the optical emission chip receives stress in the length direction, and the error rate of the optical emission chip increases, affecting the light transmission. Fig. 9 is a schematic diagram of stress generated when a light emitting chip and a circuit board are cooled according to some embodiments of the present application. As shown in fig. 9, when the optical module is cooled and the temperature decreases, the circuit board contracts in the length direction (X direction in the drawing) so that the light emitting chip receives stress in the length direction, and the error rate of the light emitting chip increases, affecting the light transmission.

Fig. 10 is a schematic cross-sectional view of a light emitting chip and a circuit board according to some embodiments of the present application. As shown in fig. 10, to reduce the error rate of the optical module, the optical module provided in the present application is provided with an emission panel, and the emission panel 302 is embedded inside the circuit board. The light emitting chips are located above the emission panel 302. The difference between the coefficient of thermal expansion of the emission panel 302 and the coefficient of thermal expansion of the light emitting chip is smaller than the difference between the coefficient of thermal expansion of the circuit board and the coefficient of thermal expansion of the light emitting chip. Therefore, when the temperature rises or decreases, the thermal expansion or cold contraction amounts of the emission panel 302 and the light emission chip are kept consistent, so that the stress action of the light emission chip is effectively reduced, the error rate is reduced, and the reliability of the light module in a high-temperature environment and a low-temperature environment is improved. The circuit board has a transmitting through hole 301, and a transmitting panel 302 is embedded inside the transmitting through hole 301.

For example, the transmitting through hole 301 may be a transmitting blind hole, that is, the transmitting panel 302 does not penetrate through the upper and lower surfaces of the circuit board, and the lower portion of the transmitting panel 302 is connected to the circuit board, and the thickness of the circuit board below the transmitting panel 302 is reduced. The lower surface of the emission panel is connected with the bottom of the emission blind hole.

Illustratively, the ratio of the difference in the coefficient of thermal expansion of the emissive panel 302 and the coefficient of thermal expansion of the light emissive chip to the difference in the coefficient of thermal expansion of the circuit board and the coefficient of thermal expansion of the light emissive chip is less than 70%. The ratio of the difference between the thermal expansion coefficient of the emission panel 302 and the thermal expansion coefficient of the light emission chip to the difference between the thermal expansion coefficient of the circuit board and the thermal expansion coefficient of the light emission chip is less than 70%, when the temperature of the optical module is increased or reduced, the difference between the thermal expansion amount of the emission panel 302 and the expansion amount of the light emission chip is less than the difference between the thermal expansion amount of the circuit board and the expansion amount of the light emission chip, so that the stress effect on the light emission chip is reduced, the error rate is reduced, and the reliability of the optical module in a high-low temperature environment is improved.

Illustratively, the ratio of the difference in the coefficient of thermal expansion of the emissive panel 302 and the coefficient of thermal expansion of the light emissive chip to the difference in the coefficient of thermal expansion of the circuit board and the coefficient of thermal expansion of the light emissive chip is less than 50%. The ratio of the difference between the thermal expansion coefficient of the emission panel 302 and the thermal expansion coefficient of the light emission chip to the difference between the thermal expansion coefficient of the circuit board and the thermal expansion coefficient of the light emission chip is less than 50%, when the temperature of the optical module is increased or reduced, the difference between the thermal expansion amount of the emission panel 302 and the expansion amount of the light emission chip is less than the difference between the thermal expansion amount of the circuit board and the expansion amount of the light emission chip, so that the stress effect on the light emission chip is reduced, the error rate is reduced, and the reliability of the optical module in a high-low temperature environment is improved.

Illustratively, the ratio of the difference in the coefficient of thermal expansion of the emissive panel 302 and the coefficient of thermal expansion of the light emissive chip to the difference in the coefficient of thermal expansion of the circuit board and the coefficient of thermal expansion of the light emissive chip is less than 30%. The ratio of the difference between the thermal expansion coefficient of the emission panel 302 and the thermal expansion coefficient of the light emission chip to the difference between the thermal expansion coefficient of the circuit board 300 and the thermal expansion coefficient of the light emission chip is less than 30%, when the temperature of the optical module is increased or decreased, the difference between the thermal expansion amount of the emission panel 302 and the expansion amount of the light emission chip is less than the difference between the thermal expansion amount of the circuit board 300 and the expansion amount of the light emission chip, so that the stress effect of the light emission chip is reduced, the error rate is reduced, and the reliability of the optical module in a high-low temperature environment is improved.

By way of example, the difference between the coefficient of thermal expansion of the emission panel 302 and the coefficient of thermal expansion of the light-emitting chip is 0, i.e., the coefficient of thermal expansion of the emission panel 302 is the same as the coefficient of thermal expansion of the light-emitting chip. The thermal expansion coefficient of the emission panel 302 is the same as the difference between the thermal expansion coefficients of the light emission chips, and when the temperature of the optical module is increased or reduced, the thermal expansion amount of the emission panel 302 is the same as the expansion amount of the light emission chips, so that the stress action of the light emission chips is reduced, the error rate is reduced, and the reliability of the optical module in a high-low temperature environment is improved.

The area of the emission panel 302 is larger than the area of the light emitting chip so that the light emitting chip is entirely located above the emission panel 302. In some examples of the present application, the light module has a first light emitting chip 421, a second light emitting chip 422, both the first light emitting chip 421 and the second light emitting chip 422 being located above the emission panel 302. The projection of the first light emitting chip 421 on the emitting panel 302 is greater than or equal to 0.35mm from the circuit board 300, so as to reduce the extrusion of the thermal expansion or thermal contraction of the circuit board 300 on the emitting panel 302 in a heated or cooled state, reduce the stress influence of the deformation of the circuit board 300 on the first light emitting chip 421, reduce the error rate of the first light emitting chip 421, and improve the reliability in a high-low temperature environment.

The projection of the second light emitting chip 422 on the emitting panel 302 is greater than or equal to 0.35mm from the circuit board 300, so that the extrusion of the thermal expansion or thermal contraction of the circuit board 300 on the emitting panel 302 in a heated or cooled state is reduced, the stress influence of the deformation of the circuit board 300 on the second light emitting chip 422 is reduced, the error rate of the first light emitting chip 421 is reduced, and the reliability in a high-low temperature environment is improved.

In some embodiments, the projection of the first light emitting chip 421 on the emitting panel 302 is less than or equal to 1.5mm, so as to reduce the thermal expansion or thermal contraction of the circuit board 300 in a heated or cooled state to stretch or squeeze the emitting panel 302, reduce the stress influence of the deformation of the circuit board 300 on the first light emitting chip 421, reduce the error rate of the first light emitting chip 421, and reduce the reliability in high and low temperature environments. Reducing the amount of space occupied by the emitter panel 302 by the circuit board 300 facilitates miniaturization of the optical module. The projection of the second light emitting chip 422 on the emitting panel 302 has a maximum distance from the circuit board 300 of less than or equal to 1.5mm, so as to reduce the extrusion of the thermal expansion or thermal contraction of the circuit board 300 on the emitting panel 302 in a heated or cooled state, reduce the stress influence of the deformation of the circuit board 300 on the second light emitting chip 422, reduce the error rate of the second light emitting chip 422, and improve the reliability in high and low temperature environments. Reducing the amount of space occupied by the emitter panel 302 by the circuit board 300 facilitates miniaturization of the optical module.

As shown in fig. 10, in some embodiments, the optical module is further provided with a laser driving chip, including a first laser driving chip 431 and a second laser driving chip 432. To facilitate driving of the light emitting chip, one end of the laser driving chip is located above the emission panel 302, and the laser driving chip is wire-bonded to the light emitting chip. For example, a first end of the first laser driving chip 431 is located above the emission panel 302, and the first laser driving chip 431 is wire-bonded to the first light emission chip 421. To achieve the electrical connection to the first laser driving chip 431, the second end of the first laser driving chip 431 is located on the circuit board 300 and is electrically connected to the circuit board 300. The first laser driving chip 431 is partially located above the emission panel 302, and another portion is located above the circuit board 300, and the first laser driving chip 431 is connected to the first light emitting chip 421.

In order to facilitate connection between the first light emitting chip 421 and the first laser driving chip 431, an output pad is disposed on an upper surface of the first end of the first laser driving chip 431, and an emitting pad is disposed on an upper surface of the first light emitting chip 421, and the output pad is connected with the emitting pad through wire bonding. In order to facilitate connection of the circuit board 300 and the first laser driving chip 431, an input pad is disposed on a lower surface of the second end of the first laser driving chip 431, and a driving pin is disposed on an upper surface of the circuit board 300 and connected to the input pad for receiving an electrical signal from the circuit board 300.

To facilitate driving of the light emitting chips, a first end of the second laser driving chip 432 is located above the emission panel 302, and the second laser driving chip 432 is wire-bonded to the second light emitting chip 422. To make electrical connection to the second laser driver chip 432, a second end of the second laser driver chip 432 is located on the circuit board 300 and is electrically connected to the circuit board 300. A part of the second laser driving chip 432 is located above the emission panel 302, another part is located above the circuit board 300, and the second laser driving chip 432 is connected to the second light emitting chip 422.

In order to facilitate connection of the second light emitting chip 422 and the second laser driving chip 432, an output pad is disposed on an upper surface of the first end of the second laser driving chip 432, an emitting pad is disposed on an upper surface of the second light emitting chip 422, and the output pad is connected with the emitting pad through wire bonding. In order to facilitate connection of the circuit board 300 and the first laser driving chip 431, an input pad is disposed on a lower surface of the second end of the second laser driving chip 432, and a driving pin is disposed on an upper surface of the circuit board 300 and connected to the input pad for receiving an electrical signal from the circuit board 300.

The emission panel 302 may be a cylindrical structure, or may be an irregularly shaped solid structure or a square structure. To facilitate the installation of the emitter panel 302 with the circuit board 300, the emitter panel 302 is a rectangular cube, and four corners of the emitter panel 302 are provided with arc-shaped chamfers.

The upper surface of the emission panel 302 is not higher than the upper surface of the circuit board 300, and the difference between the thickness of the emission panel 302 and the thickness of the circuit board 300 is less than 0.05mm, thereby facilitating the preparation. In some embodiments, the circuit board 300 is provided with a launch through hole into which the launch panel 302 is embedded.

The emitter panel 302 may be aluminum nitride.

In some embodiments of the present disclosure, the light emitting chip may be an edge emitting laser or a vertical cavity surface emitting laser. The light-emitting surface of the vertical cavity surface emitting laser faces the upper shell direction.

The application provides an optical module, comprising: the circuit board 300 and a lens assembly covering and above the circuit board 300. A light emitting chip is disposed between the circuit board 300 and the lens assembly. The circuit board 300 is provided with a transmitting through hole, and the transmitting panel 302 is positioned in the transmitting through hole. A light emitting chip is disposed above the emission panel 302, and a difference between a thermal expansion coefficient of the emission panel 302 and a thermal expansion coefficient of the light emitting chip is smaller than a difference between a thermal expansion coefficient of the circuit board 300 and a thermal expansion coefficient of the light emitting chip. Therefore, when the temperature increases or decreases, the difference between the thermal expansion or cold contraction amounts of the emission panel 302 and the light emitting chip is smaller than the difference between the thermal expansion or cold contraction amounts of the circuit board 300 and the light emitting chip, so that the stress acting on the light emitting chip is effectively reduced, the error rate is reduced, and the reliability of the light module in a high-low temperature environment is improved. The projection of the light emitting chips 420 onto the emission panel 302 is entirely within the emission panel 302. One end of the laser driver chip 430 is located above the emitter panel 302, and the laser driver chip is wire-bonded to the light emitting chip. The other end of the laser driving chip 430 is located above the circuit board 300, and the laser driving chip is wire-bonded to the circuit board 300.

The minimum distance between the projection of the light emitting chip on the emitting panel 302 and the circuit board 300 is greater than or equal to 0.35mm, so that the extrusion of the thermal expansion or thermal contraction of the circuit board 300 on the emitting panel 302 in a heated or cooled state is reduced, the stress influence of the deformation of the circuit board 300 on the light emitting chip is reduced, the error rate of the light emitting chip is reduced, and the reliability in a high-low temperature environment is improved.

Fig. 11 is a schematic diagram of a light receiving component and a circuit board structure according to some embodiments of the present application. Fig. 12 is a schematic cross-sectional view of a light receiving member and a circuit board according to some embodiments of the present application. Fig. 13 is an exploded view of a light receiving device and a circuit board according to some embodiments of the present application. As shown in fig. 11, 12 and 13, the light receiving member includes: an optical fiber connector 521, a wavelength division multiplexer 522, a receiving lens 523, a right angle prism 524, a receiving optical fiber, and a base substrate 510. The optical fiber connector 521 is composed of an optical collimator and its fixing structure, and the receiving lens 523 and the right angle prism 524 are assembled into an integral structure called receiving, which is loaded on the base substrate 510 together with the optical fiber connector 521 and the wavelength division multiplexer 522, to provide an integral coupling assembly for the high-speed light receiving device.

In the embodiment of the application, the five optical devices are integrated together, the device integration level is high, the coupling step is simplified from the previous four steps into one step, the device coupling process is greatly simplified, the coupling parameter monitoring is reduced, the coupling yield can be effectively improved, the input of coupling equipment can be reduced, and the manufacturing cost of the device is further reduced.

In this example, the optical fiber connector 521 and the receiving lens 523 are mounted on the same base substrate 510, so that the center of the optical fiber connector 521 and the center of the receiving lens are at the same height, and therefore, the offset of the light spot in the vertical direction can be controlled better, and the parallelism of the light emitting vertical direction of the wavelength division multiplexer 522 is ensured, and the receiving efficiency of the light receiving chip is ensured.

In this embodiment, the optical fiber connector 521 and the wavelength division multiplexer 522 are mounted on the same base substrate 510, so that the relative angle between the optical fiber connector 521 and the wavelength division multiplexer 522 in the vertical direction can be better controlled, that is, the light spot propagation direction after the collimation of the optical fiber connector 521 and the horizontal plane of the wavelength division multiplexer 522 keep coincident, therefore, only the horizontal angle between the optical fiber connector 521 and the wavelength division multiplexer 522 needs to be strictly controlled, and the coupling tolerance of the wavelength division multiplexer 522 is improved and the coupling difficulty is reduced.

In some embodiments, the optical fiber connector 521, the wavelength division multiplexer 522, the receiving lens 523 and the rectangular prism 524 are mounted on the same base substrate 510, and the mechanical structure is an integral structure, so that the independence of the optical paths of the components can be better ensured, and the influence of external structural changes on the optical paths can be reduced.

In some embodiments, the base substrate 510 is made of glass. Typically, the lower surface of the base substrate 510 is connected to the circuit board 300, and when the optical module is cycled at high and low temperatures, the edge at the bonding of the wavelength division multiplexer 522 and the glass is stressed and fatigued due to the deformation of the circuit board 300, so that a crack occurs between the base substrate 510 and the device. To reduce the deformation amount of the base substrate 510, a receiving bottom plate 303 is disposed under the base substrate 510. The receiving backplane 303 covers the projection of the base substrate 510 onto the circuit board 300. The elastic modulus of the receiving bottom plate 303 is greater than that of the circuit board 300, so that when the temperature of the optical module changes, the receiving bottom plate 303 generates elastic deformation, and the elastic deformation can absorb part of stress, so as to reduce the stress effect on the base substrate 510 and avoid cracking between the base substrate 510 and the device.

In some embodiments of the present application, the thickness of the receiving bottom plate 303 is less than the thickness of the circuit board 300. The circuit board 300 is provided with a receiving recess 304, and the upper surface of the receiving recess 304 is lower than the upper surface of the circuit board 300. The receiving bottom plate 303 is positioned in the receiving recess 304, and an upper surface of the receiving bottom plate 303 is flush with an upper surface of the circuit board 300 or an upper surface of the receiving bottom plate 303 is higher than an upper surface of the circuit board 300 in order to facilitate mounting of the base substrate 510. The thickness of the receiving bottom plate 303 may also be consistent with the thickness of the circuit board 300. The thickness of the receiving bottom plate 303 is smaller than that of the circuit board 300, which is advantageous in reducing costs.

In the heating or cooling process, in order to reduce the deformation difference between the circuit board 300 and the receiving bottom plate 303, the stress of the receiving bottom plate 303 is reduced, and the difference between the thermal expansion coefficient of the receiving bottom plate 303 and the thermal expansion coefficient of the circuit board 300 is less than or equal to 5ppm.

In some embodiments, the area of the receiving floor 303 is larger than the area of the base substrate 510, such that the fiber optic connector 521, the wavelength division multiplexer 522, and the receiving lens 523 are located entirely above the receiving floor 303. In some examples of the present application, a lifting substrate 530 may also be provided between the area of the receiving floor 303 and the base substrate 510, the lifting substrate 530 lifting the height of the base substrate 510. One end of the lifting substrate 530 is outside the projection range of the base substrate 510, and the light receiving chip is located below the right angle prism 524 to receive the light signal after turning the right angle prism 524.

The receiving bottom plate 303 may have a cylindrical structure, or may have an irregularly-shaped three-dimensional structure or a square structure. To facilitate the installation of the receiving bottom plate 303 and the circuit board 300, the receiving bottom plate 303 is a rectangular cube, and four corners of the receiving bottom plate 303 are provided with arc-shaped chamfers. The receiving bottom plate 303 may be aluminum nitride.

The connection between the receiving bottom plate 303 and the circuit board 300 may be either an interference connection or an adhesive connection.

Since the foregoing embodiments are all described in other modes by reference to the above, the same parts are provided between different embodiments, and the same and similar parts are provided between the embodiments in the present specification. And will not be described in detail herein.

It should be noted that in this specification, relational terms such as "first" and "second" and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, 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" or "comprising" a … … "does not exclude that an additional identical element is present in a circuit structure, article or apparatus that comprises 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 application 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 application 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 are not intended to limit the scope of the present application.

Claims (9)

1. An optical module, comprising: a circuit board having an emission through hole;

a transmitting panel embedded inside the transmitting through hole;

a light emitting chip positioned on the surface of the emitting panel, wherein the light emitted by the light emitting chip is perpendicular to the circuit board,

the lens component is positioned above the circuit board, a light emitting chip is arranged below the lens component, and the lens component changes the propagation direction of light emitted by the light emitting chip;

wherein the difference between the thermal expansion coefficient of the emission panel and the thermal expansion coefficient of the light emission chip is smaller than the difference between the thermal expansion coefficient of the circuit board and the thermal expansion coefficient of the light emission chip.

2. The light module of claim 1 wherein the light emitting chip is spaced from the edge of the emission panel by a distance greater than or equal to 1.5mm.

3. The optical module of claim 1, further comprising: a laser driving chip, the first end of which is positioned above the emission panel, and the second end of which is positioned above the circuit board;

the first end of the laser driving chip is electrically connected with the light emitting chip, and the second end of the laser driving chip is electrically connected with the circuit board.

4. A light module as recited in claim 3, wherein the first end of the laser driver chip is provided with an output pad, the output pad being electrically connected to the laser driver chip;

and the second end of the laser driving chip is provided with an input bonding pad, and the input bonding pad is electrically connected with the circuit board.

5. The optical module of claim 1, wherein a ratio of a difference in the coefficient of thermal expansion of the emission panel and the coefficient of thermal expansion of the light emitting chip to a difference in the coefficient of thermal expansion of the circuit board and the coefficient of thermal expansion of the light emitting chip is less than 30%.

6. The optical module of claim 1, wherein the light emitting chip is a vertical cavity surface emitting laser; the emission panel is made of aluminum nitride.

7. An optical module, comprising: the circuit board is provided with a blind emission hole;

a transmitting panel embedded inside the transmitting blind hole; the lower surface of the emission panel is connected with the bottom of the emission blind hole;

a light emitting chip located on a surface of the emission panel;

the lens component is positioned above the circuit board, a light emitting chip is arranged below the lens component, and the lens component changes the propagation direction of light emitted by the light emitting chip;

the difference between the thermal expansion coefficient of the emission panel and the thermal expansion coefficient of the light emission chip is smaller than the difference between the thermal expansion coefficient of the circuit board and the thermal expansion coefficient of the light emission chip;

the light emitting chip is a vertical cavity surface emitting laser, and the emission panel covers the projection of the light emitting chip.

8. The optical module of claim 7, wherein a ratio of a difference between a coefficient of thermal expansion of the emission panel and a coefficient of thermal expansion of the light emitting chip to a difference between a coefficient of thermal expansion of the circuit board and a coefficient of thermal expansion of the light emitting chip is less than 30%.

9. The optical module of claim 7, further comprising: the first end of the laser driving chip is positioned on the surface of the emission panel, and the second end of the laser driving chip is positioned on the surface of the circuit board;

the laser driving chip is electrically connected with the light emitting chip.