Optical module
By introducing microstrip lines of capacitive impedance and wire-tuning tuning of inductive impedance into the optical module, the problem of mismatch between the laser chip and the substrate impedance in the optical module is solved, and signal transmission quality and bandwidth performance are improved.
Patent Information
- Application Number
- CN202422196887.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-06
- Publication Date
- 2025-07-11
- Estimated Expiration
- 2034-09-06
AI Technical Summary
As the number of optical module transmission channels increases, the number of devices increases, and the packaging requirements increase, resulting in a mismatch of impedance between the laser chip and the substrate, causing signal reflection and affecting bandwidth.
By introducing microstrip lines of capacitive impedance and wire-tuning tuning of inductive impedance into the optical module, the impedance of the laser chip and substrate is matched to reduce the impact of sudden inductive impedance, and the microstrip lines and formation insulation design is adopted to increase fluidity and reduce signal crosstalk.
It effectively reduces signal reflection caused by impedance mismatch in laser components, ensuring the transmission quality and bandwidth performance of high-frequency signals.
Smart Images
Figure CN223092179U_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to the field of optical fiber communication technologies, and particularly 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.
[0003] Currently, to improve the transmission rate of an optical module, multiple transmission channels are provided in the optical module, that is, the transmission capacity is improved through a multi-channel design in the optical module. However, when the number of transmission channels in the optical module increases, the number of components involved will also increase, posing higher requirements for the packaging of the optical module. Utility Model Content
[0004] Some embodiments provide an optical module to facilitate ensuring the bandwidth of the optical module.
[0005] Some embodiments provide an optical module, including:
[0006] A circuit board;
[0007] An optical emission component, including a laser component, the laser component being electrically connected to the circuit board, and the laser component being configured to generate an optical signal;
[0008] Wherein, the laser component includes:
[0009] A substrate, on which a high-frequency transmission line and a first microstrip line are formed. One end of the first microstrip line is electrically connected to the high-frequency transmission line, and the width of the first microstrip line is smaller than the width of the high-frequency transmission line; a first ground layer is formed on one side of the high-frequency transmission line, and a second ground layer is formed on the other side of the high-frequency transmission line; the first ground layer surrounds the side of the first microstrip line, and the first ground layer is insulated from the first microstrip line, or the second ground layer surrounds the side of the first microstrip line, and the second ground layer is insulated from the first microstrip line;
[0010] A laser chip, disposed on the first ground layer, and an EA pad is formed on the surface of the laser chip; the laser chip is located on the side of one end of the high-frequency transmission line;
[0011] A first wire bonding, electrically connecting the EA pad and the high-frequency transmission line; the distance between the connection point of the first microstrip line and the high-frequency transmission line and the contact point of the first wire bonding and the high-frequency transmission line is less than or equal to a first preset distance.
[0012] One of the above technical solutions has the following advantages or beneficial effects:
[0013] By introducing capacitive impedance through the first microstrip line and tuning the capacitive impedance introduced by the first microstrip line with the inductive impedance introduced by the first wire bonding, the impedance on the path of the high-frequency signal input to the laser chip is pulled down, so that the impedance between the laser chip and the substrate is matched, and the influence of the sudden change of the inductive impedance introduced by the wire bonding between the laser chip and the high-frequency transmission line is reduced. Furthermore, the signal reflection caused by the impedance mismatch between the laser chip and the substrate in the laser module is reduced, and the bandwidth of the laser module is ensured.
[0014] In some embodiments, an optical module is provided. A matching pad and a second microstrip line are further formed on the surface of the substrate. The width of the second microstrip line is smaller than the width of the matching pad. The matching pad is located on the side of the laser chip, and one end of the second microstrip line is electrically connected to the matching pad.
[0015] The laser module further includes:
[0016] A matching resistor, which is disposed on the substrate and electrically connects the matching pad and the first ground layer;
[0017] A second wire bonding, which electrically connects the matching pad and the EA pad.
[0018] Another one of the above technical solutions has the following advantages or beneficial effects:
[0019] By introducing capacitive impedance through the second microstrip line and tuning the capacitive impedance introduced by the second microstrip line with the inductive impedance introduced by the second wire bonding, the impedance on the path of the high-frequency signal output is pulled down, so that the impedance between the laser chip and the substrate is matched, and the influence of the sudden change of the inductive impedance introduced by the wire bonding between the laser chip and the matching pad is reduced. Furthermore, the signal reflection caused by the impedance mismatch between the laser chip and the substrate in the laser module is reduced, and the bandwidth of the laser module is ensured.
[0020] In some embodiments, an optical module is provided. The laser module further includes a third wire bonding, which straddles above the high-frequency transmission line and one end is connected to the first ground layer and the other end is connected to the second ground layer.
[0021] Another one of the above technical solutions has the following advantages or beneficial effects:
[0022] The third wire bonding improves the connectivity between the first ground layer and the second ground layer, which is convenient for reducing the signal crosstalk on the high-frequency transmission line and ensuring the transmission quality of the high-frequency signal on the high-frequency transmission line.
[0023] In some embodiments, an optical module is provided. The laser component further includes a first resistor and a second resistor. One end of the first resistor is connected to the other end of the first microstrip line, and the other end is connected to the first ground layer or the second ground layer. One end of the second resistor is connected to the other end of the second microstrip line, and the other end is connected to the first ground layer.
[0024] Another technical solution in the above technical solutions has the following advantages or beneficial effects:
[0025] The first resistor is used to open the circuit between the first microstrip line and the ground layer, and the second resistor is used to open the circuit between the second microstrip line and the ground layer, so as to ensure the performance of the first microstrip line and the second microstrip line.
[0026] In some embodiments, an optical module is provided. The first microstrip line is strip-shaped and extends along the side of the laser chip.
[0027] The length of the first microstrip line is 235 μm, the width of the first microstrip line is 5 μm, and the distance between the side of the first microstrip line and the side of the first ground layer is not less than 5 μm.
[0028] Another technical solution in the above technical solutions has the following advantages or beneficial effects: By controlling the shape and size of the first microstrip line, it is convenient to ensure the performance of the first microstrip line.
[0029] In some embodiments, an optical module is provided. The first microstrip line is strip-shaped or bent. The length of the first microstrip line is 200 - 300 μm, the width of the first microstrip line is 3 - 10 μm, the distance between the side of the first microstrip line and the side of the first ground layer is not less than 5 μm, or the distance between the side of the first microstrip line and the side of the second ground layer is not less than 5 μm.
[0030] Another technical solution in the above technical solutions has the following advantages or beneficial effects: By controlling the shape and size of the second microstrip line, it is convenient to ensure the performance of the second microstrip line.
[0031] In some embodiments, an optical module is provided. An empty area is formed on the substrate. The empty area is located on the side of the laser chip, and the second microstrip line is located in the empty area.
[0032] The second microstrip line is bent. The length of the second microstrip line is 500 μm, and the width of the second microstrip line is 10 μm.
[0033] Another technical solution in the above technical solutions has the following advantages or beneficial effects: The empty area facilitates the setting of the second microstrip line on the substrate.
[0034] In some embodiments, an optical module is provided, including:
[0035] Circuit board;
[0036] An optical emission component, including a laser component, the laser component being electrically connected to the circuit board, and the laser component being configured to generate an optical signal;
[0037] Wherein, the laser component includes:
[0038] A substrate, on which a matching pad, a second microstrip line, and a first ground layer are formed; one end of the second microstrip line is electrically connected to the matching pad, the width of the second microstrip line is smaller than the width of the matching pad, and the matching pad and the second microstrip line are insulated from the first ground layer respectively;
[0039] A laser chip, disposed on the first ground layer, and an EA pad is formed on the surface of the laser chip; the laser chip is located at the side of the matching pad;
[0040] A matching resistor, disposed on the substrate, and the matching resistor is electrically connected to the matching pad and the first ground layer;
[0041] A second wire bonding, electrically connecting the matching pad and the EA pad.
[0042] In the optical module provided by the embodiments of the present disclosure, a capacitive impedance is introduced through the second microstrip line, and the capacitive impedance introduced by the second microstrip line is tuned with the inductive impedance introduced by the second wire bonding to lower the impedance on the high-frequency signal output path, so that the impedance between the laser chip and the substrate is matched, and the influence of the sudden change of the inductive impedance introduced by the wire bonding between the laser chip and the matching pad is reduced. Furthermore, the signal reflection caused by the impedance mismatch between the laser chip and the substrate in the laser component is reduced, and the bandwidth of the laser component is ensured.
[0043] In some embodiments, an optical module is provided, an empty area is formed on the substrate, the empty area is located at the side of the laser chip, and the second microstrip line is located within the empty area;
[0044] The second microstrip line is in a bent shape or a straight shape, the length of the second microstrip line is 500 μm, and the width of the second microstrip line is 10 μm;
[0045] The laser component further includes a second resistor, one end of the second resistor is connected to the other end of the second microstrip line, and the other end of the second resistor is connected to the first ground layer.
[0046] Another technical solution in the above technical solutions has the following advantages or beneficial effects: The empty area facilitates the setting of the second microstrip line on the substrate. The second resistor facilitates the disconnection of the second microstrip line from the ground layer.
[0047] In some embodiments, an optical module is provided. A high-frequency transmission line and a second ground layer are further formed on the substrate, and the high-frequency transmission line is located between the first ground layer and the second ground layer;
[0048] The laser component further includes:
[0049] A first bonding wire, electrically connecting the EA pad and the high-frequency transmission line;
[0050] A third bonding wire, which is spanned above the high-frequency transmission line. One end of the third bonding wire is connected to the first ground layer, and the other end of the third bonding wire is connected to the second ground layer.
[0051] Another technical solution in the above technical solutions has the following advantages or beneficial effects: The third bonding wire improves the connectivity between the first ground layer and the second ground layer, facilitates reducing signal crosstalk on the high-frequency transmission line, and ensures the transmission quality of high-frequency signals on the high-frequency transmission line. BRIEF DESCRIPTION OF THE DRAWINGS
[0052] In order to more clearly illustrate the technical solutions in the present disclosure, the following will briefly introduce the drawings required to be used in some embodiments of the present disclosure. Obviously, the drawings described below 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 described below can be regarded as schematic diagrams, and are not limitations on the actual sizes of the products, the actual processes of the methods, the actual timings of the signals, etc. involved in the embodiments of the present disclosure.
[0053] Figure 1 FIG. 21 is a partial architecture diagram of an optical communication system provided according to some embodiments of the present disclosure;
[0054] Figure 2 FIG. 25 is a partial structure diagram of a host computer provided according to some embodiments of the present disclosure;
[0055] Figure 3 FIG. 29 is a schematic structural diagram of an optical module provided according to some embodiments of the present disclosure;
[0056] Figure 4 FIG. 33 is an exploded view of an optical module provided according to some embodiments of the present disclosure;
[0057] Figure 5 FIG. 37 is a schematic structural diagram of an optical emission component provided according to some embodiments of the present disclosure;
[0058] Figure 6 FIG. 41 is a partial schematic diagram of an optical emission component provided according to some embodiments of the present disclosure;
[0059] Figure 7ASchematic diagram of a laser component provided according to some embodiments of the present disclosure;
[0060] Figure 7B Exploded view of a laser component provided according to some embodiments of the present disclosure;
[0061] Figure 8A Schematic diagram of another laser component provided according to some embodiments of the present disclosure;
[0062] Figure 8B For Figure 8A Local enlarged view at position a in;
[0063] Figure 9A Schematic diagram of another laser component provided according to some embodiments of the present disclosure;
[0064] Figure 9B For Figure 9A Local enlarged view at position b in;
[0065] Figure 10A Schematic diagram of another laser component provided according to some embodiments of the present disclosure;
[0066] Figure 10B For Figure 10A Local enlarged view at position c in;
[0067] Figure 11 Partial schematic diagram of another laser component provided according to some embodiments of the present disclosure;
[0068] Figure 12A Schematic diagram of another laser component provided according to some embodiments of the present disclosure;
[0069] Figure 12B For Figure 12A Local enlarged view at position d in;
[0070] Figure 13A Schematic diagram of another laser component provided according to some embodiments of the present disclosure;
[0071] Figure 13B For Figure 13A Local enlarged view at position e in;
[0072] Figure 14 Partial schematic diagram of another laser component provided according to some embodiments of the present disclosure;
[0073] Figure 15A A test diagram provided according to some embodiments of the present disclosure;
[0074] Figure 15B Another test diagram provided according to some examples of the present disclosure;
[0075] Figure 16 It is a schematic structural diagram of another laser component provided according to some embodiments of the present disclosure. Detailed implementation manners
[0076] Hereinafter, some embodiments of the present disclosure will be clearly and detailedly described in conjunction with 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 protection scope of the present disclosure.
[0077] Unless otherwise required by the context, throughout the specification and claims, the term "comprising" is interpreted as open and inclusive, 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 term "a plurality" means 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 indirectly connected through an intermediate medium; the use of the term "suitable for" or "configured to" means open and inclusive language, which does not exclude a device suitable for or configured to perform additional tasks or steps; descriptions such as "parallel", "perpendicular", "identical", "consistent", "flush" and the like do not limit to absolute mathematical theory relationships, but also include an acceptable error range generated in practice, and also include differences formed due to manufacturing reasons based on the same design concept.
[0078] In optical communication technologies, in order to establish information transmission between information processing devices, it is necessary to load information onto light and utilize the propagation of light to achieve information transmission. Here, the light loaded with information is an optical signal. When an optical signal is transmitted in an information transmission device, the loss of optical power can be reduced, so that high-speed, long-distance, and low-cost information transmission can be achieved. The signals that information processing devices can recognize and process are electrical signals. Information processing devices generally include optical network units (ONUs), gateways, routers, switches, mobile phones, computers, servers, tablet computers, televisions, etc., and information transmission devices generally include optical fibers and optical waveguides, etc.
[0079] The optical module can realize the mutual conversion between optical signals and electrical signals between information processing equipment and information transmission equipment. For example, 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 terminal; the first optical signal from the optical fiber is transmitted to the optical module, and the optical module converts the first optical signal into a first electrical signal, and transmits the first electrical signal to the optical network terminal; the second electrical signal from the optical network terminal is transmitted to the optical module, and the optical module converts the second electrical signal into a second optical signal, and transmits the second optical signal to the optical fiber. Since multiple information processing devices can transmit information through electrical signals, at least one of the multiple information processing devices needs to be directly connected to the optical module, and all information processing devices do not need to be directly connected to the optical module. Here, the information processing device directly connected to the optical module is called the upper computer of the optical module. In addition, the optical signal input end or the optical signal output end of the optical module can be called an optical port, and the electrical signal input end or the electrical signal output end of the optical module can be called an electrical port.
[0080] Figure 1 FIG. 1 is a partial structural diagram of an optical communication system according to some embodiments. Figure 1 As shown, the optical communication system mainly includes a remote information processing device 1000 , a local information processing device 2000 , a host computer 100 , an optical module 200 , an optical fiber 101 and a network cable 103 .
[0081] One end of the optical fiber 101 extends toward 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. The optical signal can be totally reflected in the optical fiber 101, and the propagation of the optical signal in the total reflection direction can almost maintain the original optical power. The optical signal undergoes multiple total reflections in the optical fiber 101 to transmit the optical signal from the remote information processing device 1000 to the optical module 200, or to transmit the optical signal from the optical module 200 to the remote information processing device 1000, thereby realizing long-distance, low-power loss information transmission.
[0082] The optical communication system may include one or more optical fibers 101, and the optical fibers 101 are detachably connected or fixedly connected to the optical module 200. The host computer 100 is configured to provide data signals to the optical module 200, receive data signals from the optical module 200, or monitor or control the working state of the optical module 200.
[0083] The host computer 100 includes a substantially rectangular housing and an optical module interface 102 disposed on the housing. The optical module interface 102 is configured to connect to the optical module 200 so that the host computer 100 and the optical module 200 establish a unidirectional or bidirectional electrical signal connection.
[0084] The host computer 100 further includes an external power interface, which can be connected to an electrical signal network. For example, the external power interface includes a Universal Serial Bus (USB) interface or a network cable interface 104. The network cable interface 104 is configured to connect to a network cable 103, so that the host computer 100 establishes a unidirectional or bidirectional electrical signal connection with the network cable 103. 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, so as to establish an electrical signal connection between the local information processing device 2000 and the host computer 100 through the network cable 103. For example, 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. For example, 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. It should be noted that the optical module is a tool for realizing the mutual conversion between optical signals and electrical signals. In the above process of converting optical signals and electrical signals, the information does not change, but the encoding and decoding methods of the information can change.
[0085] In addition to including an optical network terminal, the host computer 100 further includes an Optical Line Terminal (OLT), an Optical Network Terminal (ONT), or a data center server, etc.
[0086] Figure 2 It is a partial structural 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, Figure 2 only the structure of the host computer 100 related to the optical module 200 is shown. As Figure 2 shown, the host computer 100 further includes a PCB circuit board 105 disposed in the housing, a cage 106 disposed on the surface of the PCB circuit board 105, a radiator 107 disposed on the cage 106, and an electrical connector disposed inside the cage 106. The electrical connector is configured to connect to the electrical port of the optical module 200; the radiator 107 has raised structures such as fins for increasing the heat dissipation area.
[0087] 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 diffused through the radiator 107. After the optical module 200 is inserted into the cage 106, the electrical port of the optical module 200 is connected to the electrical connector inside the cage 106, thereby establishing a two-way electrical signal connection between the optical module 200 and the host computer 100. In addition, the optical port of the optical module 200 is connected to the optical fiber 101, thereby establishing a two-way optical signal connection between the optical module 200 and the optical fiber 101.
[0088] Figure 3 It is a structural diagram of an optical module provided according to some embodiments of the present disclosure. Figure 4 It is an exploded schematic diagram of an optical module provided according to some embodiments of the present disclosure. As Figure 3 and Figure 4 shown, the optical module 200 includes a shell, a circuit board 300, an optical transmitting component 400, and an optical receiving component 500 disposed within the shell.
[0089] The shell includes an upper shell 201 and a lower shell 202. The upper shell 201 covers the lower shell 202 to form the above-mentioned shell with two openings; the outer contour of the shell generally presents a rectangular body.
[0090] In some embodiments of the present disclosure, the lower shell 202 includes a bottom plate 2021 and two lower side plates 2022 located on both sides of the bottom plate 2021 and perpendicular to 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.
[0091] In some embodiments, the lower shell 202 includes a bottom plate 2021 and two lower side plates 2022 located on both sides of the bottom plate 2021 and perpendicular to the bottom plate 2021; the upper shell 201 includes a cover plate 2011 and two upper side plates 2012 located on both sides of the cover plate 2011 and perpendicular to the cover plate 2011. The two upper side plates are combined with the two lower side plates 2022 to achieve the upper shell 201 covering the lower shell 202.
[0092] The direction in which 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 the right end), and the opening 204 is also located at the end of the optical module 200 ( Figure 3The left end). Alternatively, 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. The opening 203 is an electrical port, and the gold fingers of the circuit board 300 extend from the electrical port and are inserted into the host computer (for example, the optical network terminal 100); the opening 204 is an optical port and is configured to access the optical fiber 101 so that the optical fiber 101 connects the optical transmitting component 400 and / or the optical receiving component 500 in the optical module 200.
[0093] Adopting the assembly method of combining the upper housing 201 and the lower housing 202 facilitates the installation of components such as the circuit board 300, the optical transmitting component 400, and the optical receiving component 500 into the housing, and the upper housing 201 and the lower housing 202 form a package protection for these devices. In addition, when assembling components such as the circuit board 300, the optical transmitting component 400, and the optical receiving component 500, it is convenient for the deployment of the positioning components, heat dissipation components, and electromagnetic shielding components of these devices, which is conducive to the automated implementation of production.
[0094] In some embodiments, the upper housing 201 and the lower housing 202 can be selected as needed and are generally made of metal materials, which is conducive to achieving electromagnetic shielding and heat dissipation.
[0095] In some embodiments, the optical module 200 further includes an unlocking component 600 located outside its housing. The unlocking component 600 is configured to achieve a fixed connection between the optical module 200 and the host computer, or to release the fixed connection between the optical module 200 and the host computer.
[0096] Exemplarily, the unlocking component 600 is located outside the two lower side plates 2022 of the lower housing 202 and includes a 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.
[0097] The circuit board 300 includes circuit traces, electronic components, and chips. The electronic components and chips are connected together 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, for example, capacitors, resistors, transistors, and metal-oxide-semiconductor field-effect transistors (MOSFETs). The chips may include a microcontroller unit (MCU), a laser driver chip, a limiting amplifier (LIA), a clock and data recovery (CDR) chip, a power management chip, a digital signal processing (DSP) chip, and the like.
[0098] The circuit board 300 is generally a rigid circuit board. Due to its relatively hard 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 connector in the upper computer cage.
[0099] The circuit board 300 further includes a gold finger 310 formed on its end surface. The gold finger 310 is composed of a plurality of independent pins. The circuit board 300 is inserted into the cage 106 and is conductively connected to the electrical connector in the cage 106 through the gold finger 310. The gold finger 310 can be provided only on the surface of one side of the circuit board 300 (for example Figure 4 the upper surface shown), or can be provided on the upper and lower surfaces of the circuit board 300 to adapt to the occasion with a large demand for the number of pins. The gold finger 310 is configured to establish an electrical connection with the upper computer to achieve power supply, grounding, I2C signal transmission, data signal transmission, and the like. Of course, flexible circuit boards are also used in some optical modules. The flexible circuit board is generally used in cooperation with the rigid circuit board as a supplement to the rigid circuit board.
[0100] In some embodiments, the optical transmitting component 400 and the optical receiving component 500 may be respectively disposed on the circuit board 300. Exemplarily, through holes are formed on the circuit board 300, and the optical transmitting component 400 is embedded in the through holes, and the optical receiving component 500 is disposed on the surface of the circuit board 300.
[0101] In some embodiments, the optical transmitting component 400 and the optical receiving component 500 may be 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.
[0102] In some embodiments, the optical module 200 may include an optical fiber adapter 700 and an optical fiber array 800. The optical fiber adapter 700 connects the optical transmitting component 400 and the optical receiving component 500 through the optical fiber array 800. The optical fiber array 800 includes multiple optical fibers. Exemplarily, the optical module 200 includes 2 optical fiber adapters 700, and the optical fiber array 800 includes 16 optical fibers; or, the optical module 200 includes 1 optical fiber adapter 700, and the optical fiber array 800 includes 16 optical fibers; or, the optical module 200 includes 1 optical fiber adapter 700, and the optical fiber array 800 includes 8 optical fibers, etc.
[0103] In some embodiments, the optical transmitting component 400 and the optical receiving component 500 may be located at one end of the circuit board 300 and outside the circuit board 300.
[0104] Figure 5 FIG. is a schematic structural diagram of an optical transmitting component provided according to some embodiments of the present disclosure. Figure 6 FIG. is a partial schematic diagram of an optical transmitting component provided according to some embodiments of the present disclosure. In some embodiments, as Figure 5 and Figure 6 shown, the optical transmitting component 400 may include a transmitting base 410 and a transmitting upper cover 420, and the transmitting upper cover 420 is connected to the transmitting base 410 in a covering manner. The transmitting base 410 may be embedded in the through hole of the circuit board 300, or the transmitting base 410 may be disposed on the surface of the circuit board 300.
[0105] In some embodiments, the optical transmitting component 400 may include a laser group 430, and the laser group 430 is disposed on the transmitting base 410. The laser group 430 includes multiple laser components 430a, and the laser group 430 can generate multiple optical signals.
[0106] In some embodiments, the optical transmitting component 400 may include a collimating lens group 440, and the collimating lens group 440 is disposed on the transmitting base 410 and the collimating lens group 440 is located in the light emitting direction of the laser group 430. The collimating lens group 440 includes multiple collimating lenses for collimating the optical signals generated by the laser group 430.
[0107] In some embodiments, the optical fiber array 800 may include a first optical fiber connector 810, and the first optical fiber connector 810 is disposed on the transmitting base 410. The first optical fiber connector 810 is used to fix the optical fibers in the optical fiber array 800, facilitating the optical connection between the optical fibers in the optical fiber array 800 and the optical transmitting component 400, so that the optical signals emitted by the laser group 430 can be coupled into the optical fibers of the optical fiber array 800. The first optical fiber connector 810 may be located on the side of the collimating lens group 440, so that the optical signals collimated by the collimating lens group 440 are transmitted to the first optical fiber connector 810.
[0108] In some embodiments, the optical emission component 400 may include an isolator group 450, and the isolator group 450 may be disposed on the side of the first optical fiber connector 810. When an optical signal is transmitted to the end face of the first optical fiber connector 810 or the end face of the optical fiber in the optical fiber array 800, reflection will occur. A part of the reflected optical signal will be transmitted in the direction of the laser group 430. The isolator group 450 can be used to isolate this part of the optical signal and reduce the interference of the reflected optical signal on the optical signal generated by the laser group 430. The isolator group 450 includes a plurality of isolators, and the isolators are correspondingly disposed between the collimating lens and the end face of the optical fiber in the optical fiber array 800.
[0109] Figure 7A FIG. is a schematic structural diagram of a laser component provided according to some embodiments of the present disclosure. Figure 7B FIG. is an exploded view of a laser component provided according to some embodiments of the present disclosure. In some embodiments, the laser component 430a includes a substrate 431 and a laser chip 432. A circuit pattern is formed on the substrate 431, and the laser chip 432 is mounted on the substrate 431. The laser chip 432 may be an electroabsorption modulated distributed feedback laser (EML), and an EA pad 4321 is formed on the laser chip 432. The substrate 431 may be a ceramic substrate, and the circuit pattern on the substrate 431 may be a circuit pattern formed by electroplating a metal such as gold on the ceramic substrate.
[0110] In some embodiments, a high-frequency transmission line 4311 is formed on the substrate 431, and the high-frequency transmission line 4311 extends from the edge on one side of the substrate 431 to the edge on the other side of the substrate 431. Exemplarily, one end of the high-frequency transmission line 4311 is located at the edge on one side of the substrate 431, and the other end of the high-frequency transmission line 4311 is located at the edge on the other side of the substrate 431.
[0111] In some embodiments, a first ground layer 4312 and a second ground layer 4313 are formed on the substrate 431. The first ground layer 4312 is located on one side of the high-frequency transmission line 4311, and the second ground layer 4313 is located on the other side of the high-frequency transmission line 4311. The second ground layer 4313 is connected to the first ground layer 4312. Exemplarily, the second ground layer 4313 is connected to the first ground layer 4312 at the edge on the other side of the substrate 431, so that the ground layer on the substrate 431 surrounds the side of the other end of the high-frequency transmission line 4311.
[0112] In some embodiments, the laser chip 432 is disposed on the first ground layer 4312. The laser chip 432 is located at the edge of the substrate 431 and at the edge of the other end of the high-frequency transmission line 4311.
[0113] In some embodiments, the EA pad 4321 is electrically connected to the high-frequency transmission line 4311 through the first bonding wire 433. The high-frequency transmission line 4311 and the first bonding wire 433 form a transmission path for high-frequency signals to the laser chip 432, so as to transmit the high-frequency signals input by the high-frequency transmission line 4311 to the laser chip 432 through the first bonding wire 433. The length of the first bonding wire 433 is 150 - 250 μm, such as 170 - 200 μm, etc. The first bonding wire 433 generates inductive impedance on the path from the high-frequency transmission line 4311 to the EA pad 4321.
[0114] The line width of the high-frequency transmission line 4311 is greater than the size of the EA pad 4321. In order to enable the first bonding wire 433 to connect to the EA pad 4321, the diameter of the first bonding wire 433 can be 20 - 25 μm, causing a sudden change in the inductive impedance introduced by the first bonding wire 433, resulting in impedance mismatch between the laser chip 432 and the substrate 431, causing signal reflection and reducing the bandwidth of the laser chip 432.
[0115] In some embodiments, a matching pad 4314 is formed on the substrate 431, and the matching pad 4314 is located on the side of the laser chip 432. Exemplarily, the matching pad 4314 and the high-frequency transmission line 4311 are located on different sides of the laser chip 432. A matching resistor 435 is provided on the substrate 431. One end of the matching resistor 435 is connected to the matching pad 4314, and the other end of the matching resistor 435 is connected to the first ground layer 4312. The matching resistor 435 can be a thin-film resistor. The matching pad 4314 and the matching resistor 435 form a matching circuit, and the matching circuit is used for impedance matching of the high-frequency transmission line 4311 and can consume the input DC and AC signals.
[0116] In some embodiments, the EA pad 4321 is electrically connected to the matching pad 4314 through the second bonding wire 434, so as to be electrically connected to the matching circuit through the second bonding wire 434. The length of the second bonding wire 434 is 150 - 250 μm, such as 170 - 200 μm, etc. The second bonding wire 434 generates inductive impedance on the path from the EA pad 4321 to the matching pad 4314.
[0117] The diameter of the second bonding wire 434 can be 20 - 25 μm, and it is easy to introduce a sudden change in inductive impedance through the second bonding wire 434, resulting in impedance mismatch between the laser chip 432 and the substrate 431, generating signal reflection and reducing the bandwidth of the laser chip 432.
[0118] Figure 8A It is a schematic structural diagram of another laser assembly provided according to some embodiments of the present disclosure. Figure 8B It is Figure 8A The partial enlarged view at a in Figure 8A and Figure 8BAs shown, a first microstrip line 4315 is formed on a substrate 431. The first microstrip line 4315 is electrically connected to a high-frequency transmission line 4311. The side of the first microstrip line 4315 is surrounded by a first ground layer 4312 and insulated from the first ground layer 4312. The connection point of the first microstrip line 4315 and the high-frequency transmission line 4311 is located on the side of the contact point between the high-frequency transmission line 4311 and the first wire bond 433.
[0119] In some embodiments, the first microstrip line 4315 is elongated and extends along the edge of the laser chip 432.
[0120] In the embodiments of the present disclosure, a first microstrip line 4315 is disposed around the contact point between the high-frequency transmission line 4311 and the first wire bond 433. A capacitive impedance can be introduced through the first microstrip line 4315. The capacitive impedance introduced by the first microstrip line 4315 is tuned with the inductive impedance introduced by the first wire bond 433, reducing the impedance on the path where the high-frequency signal is input to the laser chip 432, making the impedance match between the laser chip 432 and the substrate 431, reducing the influence of the sudden change in the inductive impedance introduced by the wire bond between the laser chip 432 and the high-frequency transmission line 4311, and further reducing the signal reflection in the laser module 430a caused by the impedance mismatch between the laser chip 432 and the substrate 431, ensuring the bandwidth of the laser module 430a.
[0121] In some embodiments, the distance between the connection point of the first microstrip line 4315 and the high-frequency transmission line 4311 and the contact point is less than or equal to a first preset distance to ensure the use effect of the first microstrip line 4315. Exemplarily, the first preset distance is less than or equal to 0.419 mm.
[0122] To ensure the use effect of the first microstrip line 4315, the first preset distance between the connection point of the first microstrip line 4315 and the high-frequency transmission line 4311 and the contact point should be less than
[0123] According to where c = 3×10 8 m / s, the relative permittivity εr = 8.9, and the termination frequency f = 60 GHz.
[0124] It can be obtained that
[0125] Figure 9A FIG. [FIG. NUMBER] is a schematic structural diagram of another laser module according to some embodiments of the present disclosure. Figure 9B For Figure 9A is a partial enlarged view at position b in [FIGURE REFERENCE]. In some embodiments, as Figure 9A and Figure 9B shown, the side of the first microstrip line 4315 is surrounded by a second ground layer 4313 and insulated from the second ground layer 4313.
[0126] In some embodiments, the first microstrip line 4315 extends in a direction away from the laser chip 432, such that the free end of the first microstrip line 4315 is close to the edge of the substrate 431.
[0127] Figure 10A FIG. is a schematic structural diagram of another laser assembly provided according to some embodiments of the present disclosure. Figure 10B For Figure 10A is a partial enlarged view at c in. In some embodiments, as Figure 10A and Figure 10B shown, the first microstrip line 4315 has a bent structure.
[0128] In the embodiments of the present disclosure, the shape of the first microstrip line 4315 is not limited to a long strip shape and a bent shape, and may also be a spiral shape or the like. When the first microstrip line 4315 is bent, the lengths of the bent portions can be adjusted according to the space around the first microstrip line 4315.
[0129] In some embodiments, the length of the first microstrip line 4315 is 200 - 300 μm, the width of the first microstrip line 4315 is 3 - 10 μm, the distance between the side of the first microstrip line 4315 and the first ground layer 4312 is greater than or equal to 5 μm, or the distance between the side of the first microstrip line 4315 and the second ground layer 4313 is greater than or equal to 5 μm. Exemplarily, the length of the first microstrip line 4315 is 235 μm, the width of the first microstrip line 4315 is 5 μm, and the distance between the side of the first microstrip line 4315 and the first ground layer 4312 is 5 μm.
[0130] Figure 11 FIG. is a partial schematic diagram of another laser assembly provided according to some embodiments of the present disclosure. In some embodiments, as Figure 11 shown, the laser assembly 430a may include a first resistor 436. One end of the first resistor 436 is connected to the end of the first microstrip line 4315, and the other end of the first resistor 436 is connected to the first ground layer 4312 or the second ground layer 4313. The resistance value of the first resistor 436 is not less than 1 KΩ, so as to use the first resistor 436 to achieve an open circuit between the first microstrip line 4315 and the first ground layer 4312 or the second ground layer 4313.
[0131] Figure 12A FIG. is a schematic structural diagram of another laser assembly provided according to some embodiments of the present disclosure. Figure 12B For Figure 12A is a partial enlarged view at d in. In some embodiments, as Figure 12A and Figure 12BAs shown, a second microstrip line 4316 is formed on the substrate 431. One end of the second microstrip line 4316 is connected to the matching pad 4314, and the other end of the second microstrip line 4316 is not directly connected to the ground layer on the substrate 431. For example, the other end of the second microstrip line 4316 is located at the edge of the first ground layer 4312 but does not contact the first ground layer 4312, insulating the second microstrip line 4316 from the first ground layer 4312.
[0132] In the embodiments of the present disclosure, the matching pad 4314 is connected to the second microstrip line 4316, and capacitive impedance can be introduced through the second microstrip line 4316. The capacitive impedance introduced by the second microstrip line 4316 is tuned with the inductive impedance introduced by the second wire bonding 434, reducing the impedance on the high-frequency signal output path, enabling impedance matching between the laser chip 432 and the substrate 431, reducing the impact of the sudden change in inductive impedance introduced by wire bonding between the laser chip 432 and the matching pad 4314, and further reducing signal reflection in the laser module 430a caused by impedance mismatch between the laser chip 432 and the substrate 431, ensuring the bandwidth of the laser module 430a.
[0133] In some embodiments, an empty area 4317 is formed on the substrate 431. The empty area 4317 is located on the side of the matching pad 4314 and outside the first ground layer 4312. The second microstrip line 4316 is located within the empty area 4317. The second microstrip line 4316 can be strip-shaped and can extend along the length direction of the empty area 4317.
[0134] Figure 13A FIG. is a schematic structural diagram of another laser module according to some embodiments of the present disclosure. Figure 13B is Figure 13A The partial enlarged view at e in FIG. In some embodiments, as Figure 13A and Figure 13B shown, the second microstrip line 4316 is a bent structure.
[0135] In the embodiments of the present disclosure, the shape of the second microstrip line 4316 is not limited to strip-shaped and bent, and can also be spiral-shaped, etc.
[0136] In some embodiments, the length of the second microstrip line 4316 is 400 - 600 μm, the width of the second microstrip line 4316 is 5 - 20 μm, and the distance between the side of the second microstrip line 4316 and the first ground layer 4312 is greater than 10 μm. Exemplarily, the length of the second microstrip line 4316 is 500 μm, and the width of the second microstrip line 4316 is 10 μm.
[0137] Figure 14 FIG. is a partial schematic diagram of another laser module according to some embodiments of the present disclosure. In some embodiments, as Figure 14As shown, the laser component 430a may include a second resistor 437. One end of the second resistor 437 is connected to the end of the second microstrip line 4316, and the other end of the second resistor 437 is connected to the first ground layer 4312. The resistance value of the second resistor 437 is not less than 1 KΩ to achieve an open circuit between the second microstrip line 4316 and the first ground layer 4312 by using the second resistor 437.
[0138] Figure 15A A test pattern provided according to some embodiments of the present disclosure. Figure 15B Another test pattern provided according to some examples of the present disclosure. Through experimental tests, it is found that when the first microstrip line 4315 and the second microstrip line 4316 are formed on the substrate 431, after the first microstrip line 4315 and the second microstrip line 4316 are matched, the bandwidth before -10 dB reflection can be increased from 61 GHz to 70 GHz, and the bandwidth performance in the range of 40 - 70 GHz can also be improved.
[0139] Figure 16 A schematic structural diagram of another laser component provided according to some embodiments of the present disclosure. As Figure 16 shown, the laser component 430a may include a third bonding wire 438. The third bonding wire 438 is spanned across the high-frequency transmission line 4311 to facilitate reducing signal crosstalk and ensuring the transmission quality of high-frequency signals on the high-frequency transmission line 4311. One end of the third bonding wire 438 is wire-bonded to the first ground layer 4312, and the other end of the third bonding wire 438 is wire-bonded to the second ground layer 4313. The third bonding wire 438 can improve the conductivity between the first ground layer 4312 and the second ground layer 4313.
[0140] In some embodiments, multiple third bonding wires 438 are spanned above the high-frequency transmission line 4311. By adjusting the number of the third bonding wires 438, the high-frequency impedance generated by the high-frequency transmission line 4311 can be adjusted.
[0141] In some embodiments, the laser component 430a provided by the embodiments of the present disclosure can also be used in an optical module with a coaxial package, and the laser component is disposed on a header.
[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 emission component, including a laser module, the laser module being electrically connected to the circuit board, and the laser module being configured to generate an optical signal; Wherein, the laser module includes: A substrate, on which a high-frequency transmission line and a first microstrip line are formed. One end of the first microstrip line is electrically connected to the high-frequency transmission line, and the width of the first microstrip line is smaller than the width of the high-frequency transmission line; a first ground layer is formed on one side of the high-frequency transmission line, and a second ground layer is formed on the other side of the high-frequency transmission line; the first ground layer surrounds the side of the first microstrip line, and the first ground layer is insulated from the first microstrip line, or the second ground layer surrounds the side of the first microstrip line, and the second ground layer is insulated from the first microstrip line; A laser chip, disposed on the first ground layer, and an EA pad is formed on the surface of the laser chip; the laser chip is located on the side of one end of the high-frequency transmission line; A first wire bonding, electrically connecting the EA pad and the high-frequency transmission line; the distance between the connection point of the first microstrip line and the high-frequency transmission line and the contact point of the first wire bonding and the high-frequency transmission line is less than or equal to a first preset distance.
2. The optical module according to claim 1, wherein A matching pad and a second microstrip line are further formed on the surface of the substrate, and the width of the second microstrip line is smaller than the width of the matching pad; the matching pad is located on the side of the laser chip, and one end of the second microstrip line is electrically connected to the matching pad; The laser module further includes: A matching resistor, disposed on the substrate, and the matching resistor is electrically connected to the matching pad and the first ground layer; A second wire bonding, electrically connecting the matching pad and the EA pad.
3. The optical module according to claim 1 or 2, characterized in that, The laser module further includes a third wire bonding, which straddles above the high-frequency transmission line, with one end connected to the first ground layer and the other end connected to the second ground layer.
4. The optical module according to claim 2, wherein, The laser module further includes a first resistor and a second resistor; one end of the first resistor is connected to the other end of the first microstrip line, and the other end is connected to the first ground layer or the second ground layer; one end of the second resistor is connected to the other end of the second microstrip line, and the other end is connected to the first ground layer.
5. The optical module according to claim 1, wherein The first microstrip line is in a strip shape and extends along the side of the laser chip; The length of the first microstrip line is 235μm, the width of the first microstrip line is 5μm, and the distance between the side of the first microstrip line and the side of the first ground layer is not less than 5μm.
6. The optical module according to claim 1, wherein The first microstrip line is in a strip shape or a bent shape, the length of the first microstrip line is 200 - 300μm, the width of the first microstrip line is 3 - 10μm, the distance between the side of the first microstrip line and the side of the first ground layer is not less than 5μm, or the distance between the side of the first microstrip line and the side of the second ground layer is not less than 5μm.
7. The optical module according to claim 2, wherein An empty area is formed on the substrate, the empty area is located on the side of the laser chip, and the second microstrip line is located within the empty area; The second microstrip line is in a bent shape, the length of the second microstrip line is 500μm, and the width of the second microstrip line is 10μm.
8. An optical module, characterized in that, Comprising: A circuit board; An optical emission component, including a laser assembly, the laser assembly being electrically connected to the circuit board, and the laser assembly being configured to generate an optical signal; Wherein, the laser assembly includes: A substrate, on which a matching pad, a second microstrip line, and a first ground layer are formed; one end of the second microstrip line is electrically connected to the matching pad, the width of the second microstrip line is smaller than the width of the matching pad, and the matching pad and the second microstrip line are insulated from the first ground layer respectively; A laser chip, disposed on the first ground layer, and an EA pad is formed on the surface of the laser chip; the laser chip is located at the side of the matching pad; A matching resistor, disposed on the substrate, and the matching resistor is electrically connected to the matching pad and the first ground layer; A second wire bonding, electrically connecting the matching pad and the EA pad.
9. The optical module according to claim 8, wherein An empty area is formed on the substrate, the empty area is located at the side of the laser chip, and the second microstrip line is located within the empty area; The second microstrip line is in a bent shape or a straight shape, the length of the second microstrip line is 500 μm, and the width of the second microstrip line is 10 μm; The laser assembly further includes a second resistor, one end of the second resistor is connected to the other end of the second microstrip line, and the other end of the second resistor is connected to the first ground layer.
10. The optical module according to claim 8, characterized in that, A high-frequency transmission line and a second ground layer are further formed on the substrate, and the high-frequency transmission line is located between the first ground layer and the second ground layer; The laser assembly further includes: A first wire bonding, electrically connecting the EA pad and the high-frequency transmission line; A third wire bonding, the third wire bonding straddles above the high-frequency transmission line, one end of the third wire bonding is connected to the first ground layer, and the other end of the third wire bonding is connected to the second ground layer.