Optical module
By adopting circular fixing holes and connection parts design in the optical module and combining the setting of the ground pin, the poor sealing performance and crosstalk problems during the packaging process are solved, and higher signal transmission stability and continuity are achieved.
Patent Information
- Application Number
- CN202422320990.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-23
- Publication Date
- 2025-07-11
- Estimated Expiration
- 2034-09-23
AI Technical Summary
During the packaging process of existing optical modules, the uneven deformation of the fixed holes leads to poor sealing performance, easy to leak air, and crosstalk between differential pins, affecting the signal transmission quality.
The design of differential pins through circular fixing holes and connections is adopted, combined with the setting of the grounding pins, to ensure uniformity of deformation and isolation, reduce air leakage and crosstalk, and enhance sealing performance and signal transmission continuity.
It improves the sealing performance of the optical module, reduces the possibility of air leakage in the fixed hole, reduces the crosstalk between differential pins, and ensures the stability and continuity of signal transmission.
Smart Images
Figure CN223092181U_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to the field of optical fiber communication technologies, and in particular, to an optical module. Background Art
[0002] With the development of new services and application models such as cloud computing, mobile Internet, and video, the development and progress of optical communication technologies have become increasingly important. In optical communication technologies, an optical module is a tool for realizing the mutual conversion of optical and electrical signals, and is one of the key components in optical communication devices. Moreover, with the development requirements of optical communication technologies, the transmission rate of optical modules is continuously increasing. Coaxial packaging is a commonly used optical module packaging form. Summary of the Utility Model
[0003] Some embodiments provide an optical module to facilitate ensuring the sealing performance of an optical receiving component.
[0004] Some embodiments provide an optical module, including:
[0005] A circuit board;
[0006] An optical receiving component for receiving an optical signal and converting it into an electrical signal;
[0007] A flexible circuit board electrically connecting the circuit board and the optical receiving component;
[0008] Wherein, the optical receiving component includes:
[0009] A header, on the top surface of which a photodetector and a transimpedance amplifier are provided, and the photodetector is electrically connected to the transimpedance amplifier; first fixing holes and second fixing holes are formed on the header, and there is a gap between the first fixing hole and the second fixing hole;
[0010] A first differential pin embedded in the first fixing hole and connected to the header through a first insulating layer; the top end of the first differential pin is located on the side of the transimpedance amplifier, and the first differential pin is electrically connected to the transimpedance amplifier;
[0011] A second differential pin embedded in the second fixing hole and connected to the header through a second insulating layer; the top end of the second differential pin is located on the side of the transimpedance amplifier, and the second differential pin is electrically connected to the transimpedance amplifier;
[0012] A first ground pin, the top end of which is connected to the gap between the first fixing hole and the second fixing hole on the header, so that the first ground pin is located between the first differential pin and the second differential pin;
[0013] A header cap covering the upper part of the top surface of the header.
[0014] One of the above technical solutions has the following advantages or beneficial effects: By connecting the first differential pin through the first fixing hole and connecting the second differential pin through the second fixing hole, when sealing the base and the cap, the deformations of the first fixing hole and the second fixing hole are uniform and the generated stress is uniform, reducing the possibility of air leakage in the first fixing hole and the second fixing hole, and ensuring the sealing performance of the optical receiving component. A first grounding pin is arranged between the first differential pin and the second differential pin, which is convenient for blocking the mutual crosstalk between the first differential pin and the second differential pin.
[0015] Some embodiments provide an optical module, and the optical receiving component further includes:
[0016] A second grounding pin, located on the side of the first differential pin away from the second differential pin, and the top end of the second grounding pin is electrically connected to the base;
[0017] A third grounding pin, located on the side of the second differential pin away from the first differential pin, and the top end of the third grounding pin is electrically connected to the base.
[0018] Another of the above technical solutions has the following advantages or beneficial effects: The second grounding pin is arranged on the side of the first differential pin, and the third grounding pin is arranged on the side of the second differential pin. The second grounding pin, the first differential pin, the first grounding pin, the second differential pin and the third grounding pin form a GSGSG transmission form, which can reduce the crosstalk generated by the external connection to the first differential pin and the second differential pin, and can reduce the mutual crosstalk between the first differential pin and the second differential pin.
[0019] Some embodiments provide an optical module, where the first fixing hole includes a first through portion and a first connecting portion, the size of the first through portion is smaller than that of the first connecting portion, and the projection of the first connecting portion in the direction of the top surface of the base covers the edge of the transimpedance amplifier;
[0020] The first differential pin penetrates through the first through portion, and the first differential pin is hermetically connected to the first connecting portion through the first insulating layer.
[0021] Another of the above technical solutions has the following advantages or beneficial effects: The first through portion and the first connecting portion make the first fixing hole smaller at the top and larger at the bottom. Compared with the fixing hole with a uniform cross-section, it is convenient to reduce the occupation of the space on the top surface of the base by the first fixing hole. When sealing the cap and the base, high voltage and large current cause a large amount of heat to appear in the accommodating cavity formed by the cap and the base, generating thermal stress. Since the cross-sections of the first connecting portion and the first insulating layer are circular, the deformations of the first connecting portion and the first insulating layer are uniform, and it is not easy to have air leakage in the first connecting portion.
[0022] In some embodiments, an optical module is provided. The second fixing hole includes a second through portion and a second connecting portion. The size of the second through portion is smaller than that of the second connecting portion. The projection of the second connecting portion in the direction of the top surface of the base covers the edge of the transimpedance amplifier.
[0023] The second differential pin passes through the second through portion, and the second differential pin is hermetically connected to the second connecting portion through the second insulating layer.
[0024] Another technical solution in the above technical solutions has the following advantages or beneficial effects: The second through portion and the second connecting portion make the second fixing hole smaller at the top and larger at the bottom. Compared with a fixing hole with a uniform cross-section, it is convenient to reduce the occupation of the space on the top surface of the base by the second fixing hole. When sealing the tube cap and the base, high voltage and large current cause a large amount of heat to appear in the accommodating cavity formed by the tube cap and the base, generating thermal stress. Since the cross-sections of the second connecting portion and the second insulating layer are circular, the deformation of the second connecting portion and the second insulating layer is uniform, and air leakage is not likely to occur inside the second connecting portion.
[0025] In some embodiments, an optical module is provided. The diameter of the first differential pin is smaller than that of the first ground pin, and the diameter of the second differential pin is smaller than that of the first ground pin.
[0026] Another technical solution in the above technical solutions has the following advantages or beneficial effects: The diameter of the first differential pin is smaller than that of the first ground pin, and the diameter of the second differential pin is smaller than that of the first ground pin, which is convenient for controlling the impedance continuity on the transmission link of the differential signal output by the TIA.
[0027] In some embodiments, an optical module is provided. A connecting surface is formed on the side of the base, and the connecting surface is connected to the tube cap.
[0028] The cross-sections of the first through portion and the first connecting portion are both circular. The edge of the first connecting portion is close to the connecting surface, and the first differential pin deviates from the central axis of the first connecting portion.
[0029] Another technical solution in the above technical solutions has the following advantages or beneficial effects: The edge of the first connecting portion is close to the inner edge of the connecting surface, which is convenient for fully reducing the occupation of the space on the top surface of the base by the first fixing hole and does not affect the sealing of the base and the tube cap.
[0030] In some embodiments, an optical module is provided. A connecting surface is formed on the side of the base, and the connecting surface is connected to the tube cap.
[0031] The cross-sections of the second through portion and the second connecting portion are both circular. The edge of the second connecting portion is close to the connecting surface, and the second differential pin deviates from the central axis of the second connecting portion.
[0032] Another technical solution in the above technical solutions has the following advantages or beneficial effects: The edge of the second connecting portion is close to the inner edge of the connecting surface, which is convenient for fully reducing the occupation of the space on the top surface of the base by the second fixing hole and does not affect the sealing welding of the base and the tube cap.
[0033] In some embodiments, an optical module is provided. A first boss is formed on the bottom surface of the base, and the first boss is located at the edge of the interval between the first fixing hole and the second fixing hole; the top of the first grounding pin is connected to the first boss.
[0034] Another technical solution in the above technical solutions has the following advantages or beneficial effects: The first boss facilitates the connection of the first grounding pin to the base, and the first boss is convenient for increasing the connection area between the first grounding pin and the ground on the flexible circuit board, so that the first grounding pin is fully connected to the ground on the flexible circuit board, which is convenient for ensuring the impedance continuity when the transimpedance amplifier is welded to the flexible circuit board.
[0035] In some embodiments, an optical module is provided. A second boss and a third boss are formed on the bottom surface of the base; the second boss is located at the edge of the first fixing hole and the second boss is far away from the second fixing hole, and the second grounding pin is connected to the second boss;
[0036] The third boss is located at the edge of the second fixing hole and the third boss is far away from the first fixing hole, and the third grounding pin is connected to the third boss.
[0037] Another technical solution in the above technical solutions has the following advantages or beneficial effects: The second boss facilitates the connection of the second grounding pin to the base, the third boss facilitates the connection of the third grounding pin to the base, and the second boss and the third boss are convenient for increasing the connection area between the second grounding pin, the third grounding base and the ground on the flexible circuit board, so that the second grounding pin and the third grounding pin are fully connected to the ground on the flexible circuit board, which is convenient for ensuring the impedance continuity when the transimpedance amplifier is welded to the flexible circuit board.
[0038] In some embodiments, an optical module is provided. A lens is provided on the tube cap, and the lens is located above the photodetector.
[0039] Another technical solution in the above technical solutions has the following advantages or beneficial effects: A lens is provided on the tube cap, and the lens converges the received optical signal, so that the received optical signal is transmitted to the photodetector with high coupling efficiency. BRIEF DESCRIPTION OF THE DRAWINGS
[0040] To more clearly illustrate the technical solutions in the present disclosure, the following will briefly introduce the drawings required for use in some embodiments of the present disclosure. Obviously, the drawings in the following description are only the drawings of some embodiments of the present disclosure. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings. In addition, the drawings in the following description can be regarded as schematic diagrams, and are not limitations on the actual dimensions of the products involved in the embodiments of the present disclosure, the actual processes of the methods, the actual timings of the signals, etc.
[0041] Figure 1 It is a partial architecture diagram of an optical communication system according to some embodiments;
[0042] Figure 2 It is a partial structure diagram of a host computer according to some embodiments;
[0043] Figure 3 It is a structure diagram of an optical module according to some embodiments;
[0044] Figure 4 It is an exploded view of an optical module according to some embodiments;
[0045] Figure 5 It is the structure of an optical receiving component according to some embodiments Figure 1 ;
[0046] Figure 6 It is the structure of an optical receiving component according to some embodiments Figure 2 ;
[0047] Figure 7 It is an exploded view of an optical receiving component according to some embodiments;
[0048] Figure 8 It is a bottom view of an optical receiving component according to some embodiments;
[0049] Figure 9 It is a partial decomposition of an optical receiving component according to some embodiments Figure 1 ;
[0050] Figure 10 It is a cross-section of an optical receiving component according to some embodiments Figure 1 ;
[0051] Figure 11 It is a partial decomposition of an optical receiving component according to some embodiments Figure 2 ;
[0052] Figure 12 It is a partial decomposition of an optical receiving component according to some embodiments Figure 3 ;
[0053] Figure 13Cross-section of an optical receiving component according to some embodiments Figure 2 ;
[0054] Figure 14 Cross-section of an optical receiving component according to some embodiments Figure 3 ;
[0055] Figure 15 Cross-section of an optical receiving component according to some embodiments Figure 4 。 Detailed implementation manners
[0056] Some embodiments of the present disclosure will be clearly and detailedly described below with reference to the accompanying drawings. However, the described embodiments are only a part of the embodiments of the present disclosure, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments provided by the present disclosure fall within the scope of protection of the present disclosure.
[0057] Unless otherwise required by the context, throughout the specification and the claims, the term "comprising" is interpreted in an open, inclusive sense, that is, "including, but not limited to"; the terms "first" and "second" cannot be understood as indicating or implying relative importance or an upper limit on quantity; the meaning of the term "plural" is two or more; the term "connection" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or integrated, can be directly connected, or can be indirectly connected through an intermediate medium; the use of the term "adapted to" or "configured to" means open and inclusive language, which does not exclude devices adapted to or configured to perform additional tasks or steps; descriptions such as "parallel", "perpendicular", "same", "consistent", "flush", etc. do not limit to absolute mathematical theory relationships, but also include acceptable error ranges generated in practice, and also include differences formed due to manufacturing reasons based on the same design concept.
[0058] In optical communication technologies, in order to establish information transmission between information processing devices, information is loaded onto light and the information is transmitted using the propagation speed of light. This light carrying information is an optical signal. When the optical signal is transmitted in an optical information transmission device, the loss of optical power can be reduced, and long-distance transmission of the optical signal can be achieved. At the same time, the cost of optical information transmission devices such as optical fibers is lower than that of electrical information transmission devices such as copper wires. Therefore, optical communication technologies can achieve high-speed, long-distance, and low-cost information transmission.
[0059] Information processing devices generally include optical network units (ONUs), gateways, routers, switches, mobile phones, computers, servers, tablets, televisions, etc. Optical information transmission devices generally include optical fibers and optical waveguides, etc. The signals that information processing devices can recognize and process are electrical signals, while optical communication technology uses optical signals for transmission and requires optical modules to convert between optical signals and electrical signals.
[0060] An optical module can realize the mutual conversion between optical signals and electrical signals between an information processing device and an optical information transmission device. In some embodiments, at least one of the optical signal input end or the optical signal output end of the optical module is connected to an optical fiber, and at least one of the electrical signal input end or the electrical signal output end of the optical module is connected to an optical network unit; the first optical signal from the optical fiber is transmitted to the optical module, the optical module converts the first optical signal into a first electrical signal, and transmits the first electrical signal to the optical network unit; the second electrical signal from the optical network unit is transmitted to the optical module, the optical module converts the second electrical signal into a second optical signal, and transmits the second optical signal to the optical fiber.
[0061] Since information can be transmitted between multiple information processing devices through electrical signals, at least one of the multiple information processing devices needs to be directly connected to the optical module, rather than all information processing devices being directly connected to the optical module. Here, the information processing device directly connected to the optical module is also referred to as the host computer of the optical module. In addition, the optical signal input end or the optical signal output end of the optical module is called the optical port, and the electrical signal input end or the electrical signal output end of the optical module is called the electrical port.
[0062] Figure 1 It is a partial structural diagram of an optical communication system according to some embodiments. As Figure 1 shown, the optical communication system mainly includes a remote information processing device 1000, a local information processing device 2000, a host computer 100 of the optical module, an optical module 200, an optical fiber 101, and a network cable 103. Among them, the optical fiber 101 belongs to the optical information transmission device, and the network cable 103 belongs to the electrical information transmission device.
[0063] In some embodiments, one end of the optical fiber 101 extends in the direction of the remote information processing device 1000, and the other end of the optical fiber 101 is connected to the optical module 200 through the optical port of the optical module 200. Optical signals can undergo total internal reflection in the optical fiber 101, and the propagation of optical signals in the total internal reflection direction can almost maintain the original optical power. The optical signals undergo multiple total internal reflections in the optical fiber 101 to transmit the optical signals from the remote information processing device 1000 to the optical module 200, or transmit the optical signals from the optical module 200 to the remote information processing device 1000, thereby realizing long-distance information transmission based on low power loss.
[0064] The optical communication system includes one or more optical fibers 101. In some embodiments, the optical fiber 101 is detachably connected to the optical module 200; in some embodiments, the optical fiber 101 is non - detachably connected to the optical module 200.
[0065] The host computer 100 is configured to provide a data signal to the optical module 200, or receive a data signal from the optical module 200, or monitor or control the operating state of the optical module 200.
[0066] The host computer 100 includes a housing for accommodating the optical module 200, and an optical module interface 102 provided on the housing. The optical module 200 is inserted into the housing through the optical module interface 102 to establish a unidirectional or bidirectional electrical signal connection between the host computer 100 and the optical module 200.
[0067] The host computer 100 further includes an external electrical interface, which can access an electrical signal network. In some embodiments, the external electrical interface includes a Universal Serial Bus (USB) interface or a network cable interface 104. The network cable interface 104 is configured to access a network cable 103 to establish a unidirectional or bidirectional electrical signal connection between the host computer 100 and the network cable 103.
[0068] One end of the network cable 103 is connected to the local information processing device 2000, and the other end of the network cable 103 is connected to the host computer 100 to establish an electrical signal connection between the local information processing device 2000 and the host computer 100 through the network cable 103. In some embodiments, a third electrical signal sent by the local information processing device 2000 is transmitted into the host computer 100 through the network cable 103. The host computer 100 generates a second electrical signal according to the third electrical signal. The second electrical signal from the host computer 100 is transmitted to the optical module 200. The optical module 200 converts the second electrical signal into a second optical signal and transmits the second optical signal to the optical fiber 101. The second optical signal is transmitted in the optical fiber 101 to the remote information processing device 1000.
[0069] In some embodiments, a first optical signal from the remote information processing device 1000 propagates through the optical fiber 101. The first optical signal from the optical fiber 101 is transmitted to the optical module 200. The optical module 200 converts the first optical signal into a first electrical signal. The optical module 200 transmits the first electrical signal to the host computer 100. The host computer 100 generates a fourth electrical signal according to the first electrical signal and transmits the fourth electrical signal into the local information processing device 2000.
[0070] In some embodiments, the optical module is a tool for realizing the conversion between optical signals and electrical signals. During the above conversion process of optical signals and electrical signals, the information does not change, but the encoding or decoding method of the information changes.
[0071] In addition to the optical network terminal, the host computer 100 also includes an Optical Line Terminal (OLT), an Optical Network Terminal (ONT), or a data center server, etc.
[0072] Figure 2 It is a partial structure diagram of a host computer according to some embodiments. To clearly show the connection relationship between the optical module 200 and the host computer 100, Figure 2 only the structure of the host computer 100 related to the optical module 200 is shown. As Figure 2 shown, in some embodiments, the host computer 100 further includes a PCB circuit board 105 disposed in the accommodation cavity, and a cage 106 disposed on the surface of the PCB circuit board 105; the optical module 200 is inserted into the cage 106 and fixed by the cage 106.
[0073] In some embodiments, a radiator 107 is disposed on the cage 106, which can dissipate heat for the optical module; in some embodiments, the radiator 107 has a raised structure such as fins to increase the heat dissipation area.
[0074] In some embodiments, an electrical connector is disposed inside the cage 106, and the electrical connector is configured to access the electrical port of the optical module 200.
[0075] In some embodiments, the optical module 200 is inserted into the cage 106 of the host computer 100, and the cage 106 fixes the optical module 200. The heat generated by the optical module 200 is conducted to the cage 106 and then dissipated through the radiator 107.
[0076] In some embodiments, the optical module 200 is inserted into the cage 106 of the host computer 100, and the electrical port of the optical module 200 is connected to the electrical connector inside the cage 106, so as to establish an electrical signal connection between the optical module 200 and the host computer 100.
[0077] In some embodiments, the optical port of the optical module 200 is connected to the optical fiber 101, so as to establish an optical signal connection between the optical module 200 and the optical fiber 101.
[0078] Figure 3 It is a structure diagram of an optical module according to some embodiments, Figure 4 It is an exploded view of an optical module according to some embodiments. As Figure 3 and Figure 4As shown, in some embodiments, the optical module 200 includes a shell, which includes an upper shell 201 and a lower shell 202. The upper shell 201 covers the lower shell 202 to form two openings 203 and 204, one of which is an electrical port and the other is an optical port. In some embodiments, the shell forms an opening that serves as both an electrical port and an optical port.
[0079] In some embodiments, the upper shell 201 and the lower shell 202 are made of a metal material, which is conducive to achieving electromagnetic shielding and heat dissipation.
[0080] Adopting the assembly method of combining the upper shell 201 and the lower shell 202 facilitates the installation of the circuit board 300, the optical transmitting component 400, the optical receiving component 500, etc. into the above-mentioned shell, and the upper shell 201 and the lower shell 202 can encapsulate and protect the above-mentioned devices.
[0081] The direction where the line connecting the two openings 203 and 204 is located may be consistent with the length direction of the optical module 200, or may not be consistent with the length direction of the optical module 200. For example, the opening 203 is located at the end of the optical module 200 ( Figure 3 right end), and the opening 204 is also located at the end of the optical module 200 ( Figure 3 left end). Or, the opening 203 is located at the end of the optical module 200, while the opening 204 is located at the side of the optical module 200.
[0082] In some embodiments, the lower shell 202 includes a bottom plate 2021 and two lower side plates 2022 that are perpendicular to the bottom plate 2021 and are located on both sides of the bottom plate 2021; the upper shell 201 includes a cover plate 2011, and the cover plate 2011 covers the two lower side plates 2022 of the lower shell 202 to form the above-mentioned shell.
[0083] In some embodiments, the lower shell 202 includes a bottom plate 2021 and two lower side plates 2022 that are perpendicular to the bottom plate 2021 and are located on both sides of the bottom plate 2021; the upper shell 201 includes a cover plate 2011 and two upper side plates that are perpendicular to the cover plate 2011 and are located on both sides of the cover plate 2011. The two upper side plates are combined with the two lower side plates 2022 to achieve the upper shell 201 covering the lower shell 202.
[0084] Such as Figure 3 and Figure 4As shown, in some embodiments, the optical module includes a circuit board 300 disposed within a housing. The circuit board 300 includes circuit traces, electronic components, and chips, etc. The electronic components and chips are connected according to the circuit design through the circuit traces to achieve functions such as power supply, electrical signal transmission, and grounding. The electronic components may include capacitors, resistors, triodes, Metal-Oxide-Semiconductor Field-Effect Transistors (MOSFETs). The chips may include a Microcontroller Unit (MCU), a laser driver chip, a Transimpedance Amplifier (TIA), a Limiting Amplifier (LA), a Clock and Data Recovery (CDR) chip, a power management chip, and a Digital Signal Processing (DSP) chip.
[0085] In some embodiments, the circuit board includes a rigid circuit board. Due to its relatively rigid material, the rigid circuit board can also achieve a bearing function. For example, the rigid circuit board can stably bear the above-mentioned electronic components and chips; the rigid circuit board can also be inserted into the electrical connectors in the cage 106 of the host computer 100.
[0086] In some embodiments, the circuit board further includes a flexible circuit board. The flexible circuit board can be used independently; it can also be used in cooperation with the rigid circuit board.
[0087] In some embodiments, the circuit board further includes a gold finger formed on its end surface. The gold finger is composed of a plurality of independent pins.
[0088] In some implementations, the gold finger 301 is disposed on the surface of one side of the circuit board 300 (such as Figure 4 the upper surface shown); in some implementations, the gold finger 301 is disposed on the surfaces of both the upper and lower sides of the circuit board 300 to provide a larger number of pins, so as to adapt to occasions with a large demand for the number of pins.
[0089] In some implementations, the gold finger of the circuit board extends from the electrical port 203 and is inserted into the electrical connector of the host computer 100; the circuit board is inserted into the cage 106, and the gold finger 301 is electrically connected to the electrical connector within the cage 106. The gold finger 301 is configured to establish an electrical connection with the host computer and can achieve electrical connection functions such as power supply, grounding, Inter-Integrated Circuit (I2C) signal transmission, and data signal transmission.
[0090] In some embodiments, the optical module 200 further includes an unlocking component 600 located outside its housing. The unlocking component 600 is configured to establish a fixed connection between the optical module 200 and the host computer, or to release the fixed connection between the optical module 200 and the host computer.
[0091] For example, the unlocking component 600 is located outside the two lower side plates 2022 of the lower housing 202 and includes an engaging component that matches the cage 106 of the host computer 100. When the optical module 200 is inserted into the cage 106, the engaging component of the unlocking component 600 fixes the optical module 200 in the cage 106; when the unlocking component 600 is pulled, the engaging component of the unlocking component 600 moves accordingly, thereby changing the connection relationship between the engaging component and the host computer to release the fixation of the optical module 200 to the host computer, so that the optical module 200 can be withdrawn from the cage 106.
[0092] In some embodiments, the optical transmitting component 400 and the optical receiving component 500 can be physically separated from the circuit board 300 respectively, and then electrically connected to the circuit board 300 through corresponding flexible circuit boards or electrical connectors respectively.
[0093] In some embodiments, at least one of the optical transmitting component 400 or the optical receiving component 500 is located on a side of the circuit board 300 away from the gold finger 301.
[0094] In some embodiments, at least one of the optical transmitting component or the optical receiving component can be directly disposed on the circuit board 300. For example, at least one of the optical transmitting component or the optical receiving component can be disposed on the surface of the circuit board 300 or on the side of the circuit board 300.
[0095] In some embodiments, the optical transmitting component 400 can adopt a coaxial (TO) package. The optical transmitting component 400 can include a TO socket and a TO cap covering the TO socket. Devices for emitting optical signals and devices for transmitting optical signals are disposed on the top surface of the TO socket, and various pins are disposed on the TO socket. The pins are configured to conduct electricity, transmit signals, or return current, etc.
[0096] In some embodiments, the optical receiving component 500 can adopt a TO package. The optical receiving component 500 can include a socket and a cap covering the socket. Devices for receiving optical signals and devices for processing electrical signals are disposed on the top surface of the socket, and various pins are disposed on the TO socket. The pins are configured to conduct electricity, transmit signals, or return current, etc.
[0097] In some embodiments, the optical receiving component 500 can be electrically connected to the circuit board 300 through a flexible circuit board 310.
[0098] Figure 5 For the structure of an optical receiving component according to some embodiments Figure 1 ,Figure 6 The structure of an optical receiving component according to some embodiments Figure 2 , Figure 7 is an exploded view of an optical receiving component according to some embodiments. In some embodiments, as Figures 5 - 7 shown, the optical receiving component 500 may include a header 510, and the top surface of the header 510 can be used to carry devices, such as the top surface of the header 510 carrying a photodetector, a TIA, and a matching resistor, etc.
[0099] In some embodiments, the optical receiving component 500 may include a cap 520, and the cap 520 covers the header 510, and the cap 520 and the header 510 form a relatively sealed accommodation cavity.
[0100] In some embodiments, a connection surface 511 is formed on the header 510 to connect the cap 520 through the connection surface 511. Exemplarily, the connection surface 511 is welded to connect the cap 520.
[0101] In some embodiments, an optical window is formed on the header 510 to facilitate the transmission of an optical signal from outside the cap 520 to the accommodation cavity. Exemplarily, a lens 521 is provided on the optical window, and the lens 521 is used to converge the light beam. The lens 521 converges and transmits the received optical signal to the photodetector, improving the coupling efficiency of the received optical signal to the electrical detector.
[0102] In some embodiments, the optical receiving component 500 includes pins 550, and the pins 550 include a plurality of pins, and the pins are provided on the header 510.
[0103] In some embodiments, a plurality of through holes are formed on the header 510, and the pins 550 are embedded in the through holes, and the top ends of the pins 550 penetrate through the through holes. An insulating layer formed by sealing glass or the like is provided in the through holes to fixedly connect the pins 550 and the header 510 through the insulating layer. The pins provided on the header 510 include pins for transmitting high-frequency signals, pins for transmitting DC power supply, and pins for transmitting detection signals, etc.
[0104] In some embodiments, a ground pin is also provided on the header 510, and the ground pin is electrically connected to the bottom surface of the header 510. The ground pin is used for returning high-frequency signals or DC signals, etc.
[0105] In some embodiments, a photodetector 530 and a TIA 540 may be disposed on the top surface of the socket 510. The bottom of the photodetector 530 and the bottom of the TIA 540 are respectively connected to the socket 510, and the photodetector 530 is located on the side of the TIA 540. The photodetector 530 may be wire-bonded to the TIA 540. The photodetector 530 receives an optical signal and converts it into a current signal, and transmits the current signal to the TIA 540 through wire bonding. The TIA 540 shapes and processes the current signal to output a voltage signal, and the voltage signal may be a differential signal. The photodetector 530 may be welded to the socket 510, and the TIA 540 may be welded to the socket 510.
[0106] In some embodiments, a substrate may be disposed below the photodetector 530. The top of the substrate may be supported and connected to the photodetector 530, and the bottom of the substrate is welded to the socket 510. The substrate may adjust the relative height between the top surface of the photodetector 530 and the top surface of the TIA 540 to facilitate wire bonding of the photodetector 530 to the TIA 540.
[0107] In some embodiments, a first fixing hole 512 is formed in the socket 510. The first fixing hole 512 penetrates the bottom surface and the top surface of the socket 510. The top of the first fixing hole 512 extends to the side of the TIA 540. Exemplarily, the top edge of the first fixing hole 512 extends to the bottom of the edge of the TIA 540.
[0108] In some embodiments, the cross-section of the first fixing hole 512 is circular. The circular first fixing hole 512 deforms uniformly and generates uniform stress, which is convenient for sealing the first fixing hole 512, and further facilitates ensuring the sealing performance at the first fixing hole 512 on the socket 510 and reducing the possibility of air leakage at the first fixing hole 512.
[0109] In some embodiments, the pin 550 may include a first differential pin 551. The first differential pin 551 is embedded in the first fixing hole 512 so that the top of the first differential pin 551 is located on the side of the TIA 540. The first differential pin 551 may be wire-bonded to the TIA 540, and the differential signal output by the TIA 540 is output through the first differential pin 551.
[0110] In some embodiments, a second fixing hole 513 is formed in the socket 510. The second fixing hole 513 penetrates the bottom surface and the top surface of the socket 510. The top of the second fixing hole 513 extends to the side of the TIA 540. Exemplarily, the top edge of the second fixing hole 513 extends to the bottom of the edge of the TIA 540. There is a gap between the second fixing hole 513 and the first fixing hole 512 to facilitate mutual isolation between the second fixing hole 513 and the first fixing hole 512.
[0111] In some embodiments, the cross-section of the second fixing hole 513 is circular. The circular second fixing hole 513 deforms uniformly and generates uniform stress, which facilitates the sealing of the second fixing hole 513. Furthermore, it is convenient to ensure the sealing performance at the second fixing hole 513 on the socket 510 and reduce the possibility of air leakage at the second fixing hole 513.
[0112] In some embodiments, the pin 550 may include a second differential pin 552. The second differential pin 552 is embedded in the second fixing hole 513, and the top end of the second differential pin 552 is located at the side of the TIA 540. The second differential pin 552 can be wire-bonded to the TIA 540, and the differential signal output by the TIA 540 is transmitted through the second differential pin 552.
[0113] The first differential pin 551 and the second differential pin 552 are close to form a differential line to transmit the differential signal output by the TIA 540. By using the interval between the second fixing hole 513 and the first fixing hole 512, the first differential pin 551 and the second differential pin 552 are isolated from each other, which is convenient for reducing the crosstalk of the signals between the first differential pin 551 and the second differential pin 552.
[0114] In some embodiments, the pin 550 may include a first ground pin 553. The top end of the first ground pin 553 is connected to the bottom surface of the socket 510. The first ground pin 553 is located between the first differential pin 551 and the second differential pin 552, so that the first ground pin 553 is close to the first differential pin 551 and the second differential pin 552 respectively, which is convenient for blocking the mutual crosstalk between the first differential pin 551 and the second differential pin 552.
[0115] In some embodiments, the pin 550 may include a second ground pin 554. The top end of the second ground pin 554 is connected to the bottom surface of the socket 510. The second ground pin 554 is located at the side of the first differential pin 551 and is far away from the second differential pin 552, so that the side of the first differential pin 551 is provided with the first ground pin 553 and the second ground pin 554.
[0116] In some embodiments, the pin 550 may include a third ground pin 555. The top end of the third ground pin 555 is connected to the bottom surface of the socket 510. The third ground pin 555 is located at the side of the second differential pin 552 and is far away from the first differential pin 551, so that the side of the second differential pin 552 is provided with the first ground pin 553 and the third ground pin 555.
[0117] In some embodiments, the second ground pin 554, the first differential pin 551, the first ground pin 553, the second differential pin 552, and the third ground pin 555 form a GSGSG transmission form, which can reduce the crosstalk generated by the external connection to the first differential pin 551 and the second differential pin 552, and can reduce the mutual crosstalk between the first differential pin 551 and the second differential pin 552.
[0118] In some embodiments, the pin 550 further includes a first pin 556, and the top of the first pin 556 penetrates through the top surface of the socket 510. The first pin 556 is electrically connected to the photodetector 530 or the TIA 540, etc., to transmit a supply current, etc. to the photodetector 530 or the TIA 540. The pin 550 may include a plurality of first pins 556.
[0119] Figure 8 Is a bottom view of an optical receiving component according to some embodiments, Figure 8 Showing an arrangement of pins on the socket. In some embodiments, the first differential pin 551, the second differential pin 552, etc. are arranged in sequence along the edge close to the socket 510. In this way, the first differential pin 551, the second differential pin 552, etc. are far from the middle position of the socket 510, so as to leave enough space for the photodetector 430, etc. on the top surface of the socket 510. Exemplarily, the first differential pin 551, the second differential pin 552, etc. are close to the edge of the connection surface 511.
[0120] In some embodiments, the pin 550 includes 3 first pins 556, and the 3 first pins 556 are arranged side by side along the edge close to the socket 510. In this way, the first pin 556 is far from the middle position of the socket 510, so as to leave enough space for the photodetector 430, etc. on the top surface of the socket 510. Exemplarily, the 3 first pins 556 are close to the edge of the connection surface 511.
[0121] In some embodiments, a first boss 514 is formed on the bottom surface of the socket 510. The first boss 514 is disposed within the interval between the first fixing hole 512 and the second fixing hole 513, and the top end of the first ground pin 553 is connected to the first boss 514. Exemplarily, the first boss 514 is located at the edge of the interval between the first fixing hole 512 and the second fixing hole 513. The first boss 514 facilitates the connection of the first ground pin 553 to the socket 510, and the first boss 514 is convenient for increasing the connection area between the first ground pin 553 and the ground on the flexible circuit board 310, so that the first ground pin 553 is fully connected to the ground on the flexible circuit board 310, which is convenient for ensuring the impedance continuity when the TIA 540 is welded to the flexible circuit board 310.
[0122] In some embodiments, a second boss 515 is formed on the bottom surface of the socket 510. The second boss 515 is located at the edge of the first fixing hole 512 and the second boss 515 is away from the second fixing hole 513. The top end of the second ground pin 554 is connected to the second boss 515. The second boss 515 facilitates the connection of the second ground pin 554 to the socket 510, and the second boss 515 is convenient for increasing the connection area between the second ground pin 554 and the ground on the flexible circuit board 310, so that the second ground pin 554 is fully connected to the ground on the flexible circuit board 310, which is convenient for ensuring the impedance continuity when the TIA 540 is welded to the flexible circuit board 310.
[0123] In some embodiments, a third boss 516 is formed on the bottom surface of the socket 510. The third boss 516 is located at the edge of the second fixing hole 513 and the third boss 516 is away from the first fixing hole 512. The top end of the third ground pin 555 is connected to the third boss 516. The third boss 516 facilitates the connection of the third ground pin 555 to the socket 510, and the third boss 516 is convenient for increasing the connection area between the third ground pin 555 and the ground on the flexible circuit board 310, so that the third ground pin 555 is fully connected to the ground on the flexible circuit board 310, which is convenient for ensuring the impedance continuity when the TIA 540 is welded to the flexible circuit board 310.
[0124] Figure 9 Partial decomposition of an optical receiving component according to some embodiments Figure 1 , Figure 10 Cross-section of an optical receiving component according to some embodiments Figure 1 . In some embodiments, as Figure 9 and Figure 10 shown, a first insulating layer 561 is disposed in the first fixing hole 512. The first differential pin 551 is embedded and connected to the first insulating layer 561 to fix the first differential pin 551 in the first fixing hole 512 through the first insulating layer 561.
[0125] In some embodiments, the first insulating layer 561 may be formed by solidifying molten glass, which is convenient for sealing and connecting the first differential pin 551 and the first fixing hole 512. Exemplarily, the glass may be glass with a preset dielectric constant ε, which is convenient for designing the impedance on the differential signal path transmitted by the first differential pin 551 based on the diameter of the first differential pin 551, the length of the first differential pin 551, the diameter of the first fixing hole 512, etc. Therefore, the diameter of the second fixing hole 513 can be designed based on the impedance requirements on the differential signal path transmitted by the first differential pin 551.
[0126] In some embodiments, the impedance on the differential signal path transmitted by the first differential pin 551 Among them, L represents inductance and C represents capacitance. The magnitude of inductance L is related to the diameter and length of the first differential pin 551; the smaller the diameter of the first differential pin 551 and the longer the length, the larger the inductance L; the larger the diameter of the first differential pin 551 and the shorter the length, the smaller the inductance L. Capacitance C is related to the diameter of the first insulating layer 561, the dielectric constant of the first insulating layer 561, and the contact area between the first differential pin 551 and the first insulating layer 561.
[0127] In some embodiments, a second insulating layer 562 is disposed in the second fixing hole 513. The second differential pin 552 is embedded and connected to the second insulating layer 562 to fix the second differential pin 552 in the second fixing hole 513 through the second insulating layer 562.
[0128] In some embodiments, the second insulating layer 562 can be formed by solidifying molten glass, which is convenient for hermetically connecting the second differential pin 552 and the inside of the second fixing hole 513. Exemplarily, the glass can be glass with a preset dielectric constant ε, which is convenient for designing the impedance on the differential signal transmission path of the second differential pin 552 based on the diameter of the second differential pin 552, the length of the second differential pin 552, the diameter of the second fixing hole 513, etc. Therefore, the diameter of the second fixing hole 513 can be designed based on the impedance requirement on the differential signal transmission path of the second differential pin 552.
[0129] Figure 11 Partial decomposition of an optical receiving component according to some embodiments Figure 2 , Figure 12 Partial decomposition of an optical receiving component according to some embodiments Figure 3 , Figure 13 Cross-section of an optical receiving component according to some embodiments Figure 2 , Figure 14 Cross-section of an optical receiving component according to some embodiments Figure 3 . Figures 11 - 14 The structure of a first fixing hole 512 and a second fixing hole 513 and the usage state of the first fixing hole 512 and the second fixing hole 513 are shown.
[0130] In some embodiments, the first fixing hole 512 includes a first through portion 5121 and a first connecting portion 5122. The first through portion 5121 is located above the first connecting portion 5122, and the first through portion 5121 communicates with the first connecting portion 5122. The size of the first through portion 5121 is smaller than that of the first connecting portion 5122, and the projection of the first connecting portion 5122 in the direction of the top surface of the header 510 covers the edge of the TIA 540; the edge of the first through portion 5121 is close to the edge of the TIA 540. In this way, the first through portion 5121 and the first connecting portion 5122 make the first fixing hole 512 smaller at the top and larger at the bottom, which is convenient for reducing the occupation of the space on the top surface of the header 510 compared with a fixing hole with a uniform cross-section.
[0131] In some embodiments, the edge pads of the TIA 540 are not directly above the first through portion 5121, that is, the projection of the edge pads of the TIA 540 in the direction of the top surface of the header 510 is not within the first through portion 5121. In this way, when wire bonding is performed on the TIA 540, the top surface of the header 510 can fully support the TIA 540, reducing the damage to the TIA 540 caused by the suspension under the pads of the TIA 540.
[0132] In some embodiments, the cross-section of the first connecting portion 5122 is circular, and the edge of the first connecting portion 5122 is close to the inner edge of the connecting surface 511. In this way, it is convenient to fully reduce the occupation of the space on the top surface of the header 510 by the first fixing hole 512, and it does not affect the sealing welding between the header 510 and the tube cap 520.
[0133] In some embodiments, the first insulating layer 561 is embedded in the first connecting portion 5122, and the first insulating layer 561 seals the first connecting portion 5122. The cross-section of the first connecting portion 5122 is circular, so that the cross-section of the first insulating layer 561 is circular. When the tube cap 520 and the header 510 are sealed and welded, a large amount of heat appears in the accommodation cavity formed by the tube cap 520 and the header 510 under high voltage and large current, generating thermal stress. Since the cross-sections of the first connecting portion 5122 and the first insulating layer 561 are circular, the deformation of the first connecting portion 5122 and the first insulating layer 561 is uniform, and air leakage is not likely to occur in the first connecting portion 5122.
[0134] In some embodiments, no insulating layer is provided in the first through portion 5121 to reduce the unevenness at the top end of the first through portion 5121 caused by the insulating layer material when an insulating layer is provided in the first through portion 5121, which affects the mounting of the TIA 540 on the top surface of the header 510.
[0135] In some embodiments, the second fixing hole 513 includes a second through portion 5131 and a second connecting portion 5132. The second through portion 5131 is located above the second connecting portion 5132, and the second through portion 5131 communicates with the second connecting portion 5132. The size of the second through portion 5131 is smaller than that of the second connecting portion 5132. The projection of the second connecting portion 5132 in the direction of the top surface of the header 510 covers the edge of the TIA 540; the edge of the second through portion 5131 is close to the edge of the TIA 540. Thus, the second through portion 5131 and the second connecting portion 5132 make the second fixing hole 513 smaller at the top and larger at the bottom. Compared with a fixing hole with a uniform cross-section, it is convenient to reduce the occupation of the space on the top surface of the header 510 by the second fixing hole 513.
[0136] In some embodiments, the edge pads of the TIA 540 are not directly above the second through portion 5131, that is, the projection of the edge pads of the TIA 540 in the direction of the top surface of the header 510 is not within the second through portion 5131. In this way, when wire bonding is performed on the TIA 540, the top surface of the header 510 can fully support the TIA 540, reducing the damage to the TIA 540 caused by suspension under the pads of the TIA 540.
[0137] In some embodiments, the cross-section of the second connecting portion 5132 is circular, and the edge of the second connecting portion 5132 is close to the inner edge of the connecting surface 511. This is convenient for fully reducing the occupation of the space on the top surface of the header 510 by the second fixing hole 513 and does not affect the sealing welding of the header 510 and the tube cap 520.
[0138] In some embodiments, the second insulating layer 562 is embedded in the second connecting portion 5132, and the second insulating layer 562 seals the second connecting portion 5132. The cross-section of the second connecting portion 5132 is circular, so that the cross-section of the second insulating layer 562 is circular. When the tube cap 520 and the header 510 are sealed and welded, a large amount of heat is generated in the accommodating cavity formed by the tube cap 520 and the header 510 under high voltage and large current, generating thermal stress. Since the cross-sections of the second connecting portion 5132 and the second insulating layer 562 are circular, the deformation of the second connecting portion 5132 and the second insulating layer 562 is uniform, and air leakage is not likely to occur in the second connecting portion 5132.
[0139] In some embodiments, no insulating layer is provided in the second through portion 5131 to reduce the unevenness at the top end of the second through portion 5131 caused by the use of a large amount of insulating material in the second through portion 5131, which affects the mounting of the TIA 540 on the top surface of the header 510.
[0140] Figure 15 Cross-section of an optical receiving component according to some embodiments Figure 4 In some embodiments, such as Figure 15As shown, the first differential pin 551 deviates from the central axis of the first connection portion 5122. The first differential pin 551 is closer to the edge of the connection surface 511 than the central axis of the first connection portion 5122, causing the first differential pin 551 to deviate from the center of the first insulating layer 561. Since the first differential pin 551 is not located at the center of the first connection portion 5122, the first differential pin 551 can be closer to the edge of the socket 510, facilitating leaving sufficient space on the fixed surface of the socket for arranging the photodetector 530, etc.
[0141] In some embodiments, the second differential pin 552 deviates from the central axis of the second connection portion 5132. The second differential pin 552 is closer to the edge of the connection surface 511 than the central axis of the second connection portion 5132, causing the second differential pin 552 to deviate from the center of the second insulating layer 562. Since the second differential pin 552 is not located at the center of the second connection portion 5132, the second differential pin 552 can be closer to the edge of the socket 510, facilitating leaving sufficient space on the fixed surface of the socket for arranging the photodetector 530, etc.
[0142] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present disclosure, and are not intended to limit them; although the present disclosure has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present disclosure.
Claims
1. An optical module, characterized in that, Comprising: A circuit board; An optical receiving component for receiving an optical signal and converting it into an electrical signal; A flexible circuit board electrically connecting the circuit board and the optical receiving component; Wherein, the optical receiving component includes: A header, on the top surface of which a photodetector and a transimpedance amplifier are provided, and the photodetector is electrically connected to the transimpedance amplifier; a first fixing hole and a second fixing hole are formed on the header, and there is a gap between the first fixing hole and the second fixing hole; A first differential pin embedded in the first fixing hole and connected to the header through a first insulating layer; the top end of the first differential pin is located at the side of the transimpedance amplifier, and the first differential pin is electrically connected to the transimpedance amplifier; A second differential pin embedded in the second fixing hole and connected to the header through a second insulating layer; the top end of the second differential pin is located at the side of the transimpedance amplifier, and the second differential pin is electrically connected to the transimpedance amplifier; A first ground pin, the top end of which is connected within the gap between the first fixing hole and the second fixing hole on the header, so that the first ground pin is located between the first differential pin and the second differential pin; A cap covering the top surface of the header.
2. The optical module according to claim 1, wherein The optical receiving component further includes: A second ground pin located on the side of the first differential pin away from the second differential pin, and the top end of the second ground pin is electrically connected to the header; A third ground pin located on the side of the second differential pin away from the first differential pin, and the top end of the third ground pin is electrically connected to the header.
3. The optical module according to claim 1 or 2, characterized in that, The first fixing hole includes a first through portion and a first connecting portion, the size of the first through portion is smaller than the size of the first connecting portion, and the projection of the first connecting portion in the direction of the top surface of the header covers the edge of the transimpedance amplifier; The first differential pin penetrates through the first through portion, and the first differential pin is hermetically connected to the first connecting portion through the first insulating layer.
4. The optical module according to claim 1 or 2, characterized in that, The second fixing hole includes a second through portion and a second connecting portion, the size of the second through portion is smaller than the size of the second connecting portion, and the projection of the second connecting portion in the direction of the top surface of the header covers the edge of the transimpedance amplifier; The second differential pin penetrates through the second through portion, and the second differential pin is hermetically connected to the second connecting portion through the second insulating layer.
5. The optical module according to claim 1, wherein The diameter of the first differential pin is smaller than the diameter of the first ground pin, and the diameter of the second differential pin is smaller than the diameter of the first ground pin.
6. The optical module according to claim 3, wherein A connecting surface is formed on the side of the header, and the connecting surface connects the cap; The cross-sections of the first through portion and the first connecting portion are both circular, the edge of the first connecting portion is close to the connecting surface, and the first differential pin deviates from the central axis of the first connecting portion.
7. The optical module according to claim 4, wherein A connecting surface is formed on the side of the header, and the connecting surface connects the cap; The cross-sections of the second through portion and the second connecting portion are both circular, the edge of the second connecting portion is close to the connecting surface, and the second differential pin deviates from the central axis of the second connecting portion.
8. The optical module according to claim 1, wherein A first boss is formed on the bottom surface of the socket, and the first boss is located at the edge of the interval between the first fixing hole and the second fixing hole; the top of the first grounding pin is connected to the first boss.
9. The optical module according to claim 2, characterized in that, A second boss and a third boss are formed on the bottom surface of the socket; the second boss is located at the edge of the first fixing hole and the second boss is away from the second fixing hole, and the second grounding pin is connected to the second boss; The third boss is located at the edge of the second fixing hole and the third boss is away from the first fixing hole, and the third grounding pin is connected to the third boss.
10. The optical module according to claim 1, wherein A lens is provided on the tube cap, and the lens is located above the photodetector.