An optical module

Abstract

The application provides an optical module comprising a lens assembly. The lens assembly comprises a cover cavity, the cover cavity is arranged on an optical chip of a circuit board, the cover cavity has a second side wall, a second bottom surface and a third side wall, a fourth side wall is arranged on a side of the second side wall adjacent to the second bottom surface, the fourth side wall is more concave than the second side wall; the third side wall is located on a side of the second bottom surface, one end of the third side wall is connected with one end of the second side wall, a fifth side wall is arranged on a side of the third side wall adjacent to the second bottom surface, the fifth side wall is more concave than the third side wall. In the application, the fourth side wall and the fifth side wall are arranged, the side wall of the cover cavity is thinned, the capillary phenomenon between the cover cavity and the circuit board is reduced, and the amount of glue entering the lens assembly is obviously reduced; the arrangement of the fourth side wall also increases the distance between the optical chip and the second side wall, further reduces the penetration of glue into the lens assembly, and thus avoids the pollution of various devices in the lens assembly.

Description

[0001] This application is a divisional application. The original application has the application number 202010900621.0 and the original application date is August 31, 2020. The entire contents of the original application are incorporated herein by reference. Technical Field

[0002] This application relates to the field of communication technology, and in particular to an optical module. Background Technology

[0003] Traditional COB optical modules consist of three parts: a circuit board, an optical chip, and a lens assembly. The optical chip is attached to the surface of the circuit board, and the lens assembly covers the optical chip and is fixed to the surface of the circuit board with adhesive.

[0004] When a lens assembly is fixed to the surface of a circuit board with adhesive, the adhesive is typically applied to both sides of the lens assembly. Because the adhesive has good fluidity at high temperatures, and there is a gap of approximately 30-60 micrometers between the lens assembly and the circuit board, the adhesive, under the influence of surface tension between the two materials, seeps through this gap into the bottom of the lens assembly. Furthermore, since the circuit board needs to power the optical chip, its surface has many exposed power and signal traces that pass through the bottom of the lens assembly. When the adhesive seeps through this gap into the bottom of the lens assembly, it contaminates the power and signal traces, and may also contaminate the optical chip along with the signal traces. Summary of the Invention

[0005] This application provides an optical module that prevents adhesive from entering the bottom of the lens assembly and thus contaminating the various components covered by the lens assembly.

[0006] An optical module, comprising:

[0007] Circuit board;

[0008] An optical chip, mounted on a circuit board, is used to generate or receive optical signals.

[0009] The lens assembly, connected to the circuit board and covering the optical chip, is used to change the propagation direction of the optical signal;

[0010] The lens assembly includes a cover cavity;

[0011] The covering cavity has a second sidewall, a second bottom surface and a third sidewall, and is used to cover the optical chip;

[0012] The second sidewall has a fourth sidewall on the side adjacent to the second bottom surface; the fourth sidewall is more recessed than the second sidewall.

[0013] The third sidewall is located on one side of the second bottom surface, with one end connected to one end of the second sidewall. A fifth sidewall is provided on the side adjacent to the second bottom surface; the fifth sidewall is more recessed than the third sidewall.

[0014] Beneficial Effects: This application provides an optical module, including a circuit board, an optical chip disposed on the circuit board, and a lens assembly connected to the circuit board. The optical chip is used to generate or receive optical signals. The lens assembly covers the optical chip and is used to change the propagation direction of the optical signal. The lens assembly includes a fixing member. The lens assembly includes a covering cavity that covers the optical chip. The covering cavity has a second sidewall, a second bottom surface, and a third sidewall. A fourth sidewall is provided on the side of the second sidewall adjacent to the second bottom surface. The fourth sidewall is more recessed than the second sidewall. The provision of the fourth sidewall is equivalent to thinning the second sidewall. Thinning the second sidewall can reduce the capillary effect between the second sidewall and the circuit board, resulting in a significant reduction in the amount of adhesive entering the lens assembly. Since the optical chip is located near the second sidewall, the provision of the fourth sidewall is equivalent to increasing the distance between the optical chip and the second sidewall. Because the amount of adhesive is significantly reduced and the distance between the optical chip and the second sidewall is increased, the adhesive entering the lens assembly enters the fourth sidewall and does not enter the second bottom surface. The third sidewall is located on one side of the second bottom surface, with one end connected to one end of the second sidewall. A fifth sidewall is provided on the side of the third sidewall adjacent to the second bottom surface, and this fifth sidewall is more recessed than the third sidewall. The fifth sidewall effectively thins the third sidewall. Thinning the third sidewall reduces capillary action between the third sidewall and the circuit board, significantly reducing the amount of adhesive entering the lens assembly. In this application, a fourth sidewall, more recessed than the second sidewall, is provided on the side of the second sidewall closest to the second bottom surface, and a fifth sidewall, more recessed than the third sidewall, is provided on the side of the third sidewall adjacent to the second bottom surface. Thinning the sidewall of the enclosure cavity reduces capillary action between the enclosure cavity and the circuit board, significantly reducing the amount of adhesive entering the lens assembly. The fourth sidewall, more recessed than the second sidewall, also increases the distance between the optical chip and the second sidewall, further reducing adhesive penetration into the lens assembly and thus preventing contamination of the components within the lens assembly. Attached Figure Description

[0015] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the connection relationship between optical communication terminals;

[0017] Figure 2 This is a schematic diagram of an optical network terminal structure;

[0018] Figure 3This is a schematic diagram of an optical module structure provided in an embodiment of this application;

[0019] Figure 4 This is a schematic diagram of the exploded structure of an optical module provided in an embodiment of this application;

[0020] Figure 5 An exploded view of the lens assembly and circuit board provided in an embodiment of this application;

[0021] Figure 6 An exploded view of the fiber array, fiber plug, lens assembly, and circuit board provided in the embodiments of this application;

[0022] Figure 7 An exploded view of the lens assembly and circuit board provided in an embodiment of this application from another angle;

[0023] Figure 8 This is a schematic diagram of the lens assembly provided in an embodiment of this application;

[0024] Figure 9 A first cross-sectional view of the lens assembly and circuit board provided in an embodiment of this application;

[0025] Figure 10 A second cross-sectional view of the lens assembly and circuit board provided in an embodiment of this application;

[0026] Figure 11 This is a third cross-sectional view of the lens assembly and circuit board provided in an embodiment of this application. Detailed Implementation

[0027] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0028] The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The singular forms “a” and “the” as used in this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0029] The following detailed description of some embodiments of this application is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0030] One of the core aspects of fiber optic communication is the conversion between optical and electrical signals. Fiber optic communication uses optical signals carrying information to transmit in information transmission equipment such as optical fibers / waveguides. The passive transmission characteristics of light in optical fibers / waveguides enable low-cost, low-loss information transmission. In contrast, information processing equipment such as computers uses electrical signals. Therefore, in order to establish an information connection between information transmission equipment such as optical fibers / waveguides and information processing equipment such as computers, it is necessary to achieve the conversion between electrical and optical signals.

[0031] In the field of optical fiber communication technology, optical modules realize the mutual conversion between optical and electrical signals, which is the core function of optical modules. Optical modules achieve electrical connection with external host computers through gold fingers on their internal circuit boards. The main electrical connections include power supply, I2C signals, data signals, and grounding. Optical modules achieve optical connection with external optical fibers through optical interfaces. There are various connection methods for external optical fibers, resulting in various types of fiber optic connectors. Using gold fingers at the electrical interface for electrical connection has become the mainstream connection method in the optical module industry. Based on this, the pin definitions on the gold fingers have formed various industry protocols / standards. The optical connection method using optical interfaces and fiber optic connectors has also become the mainstream connection method in the optical module industry. Based on this, various industry standards for fiber optic connectors have been formed, such as LC interface, SC interface, and MPO interface. The optical interface of the optical module also has an adaptive structure design for fiber optic connectors, resulting in various types of fiber optic adapters at the optical interface.

[0032] Figure 1 This is a schematic diagram illustrating the connection relationships between optical communication terminals. For example... Figure 1 As shown, the connection of the optical communication terminal mainly includes the interconnection between the optical network terminal 100, the optical module 200, the optical fiber 101, and the network cable 103.

[0033] One end of the optical fiber 101 is connected to the remote server, and one end of the network cable 103 is connected to the local information processing device. The connection between the local information processing device and the remote server is completed by the connection between the optical fiber 101 and the network cable 103. The connection between the optical fiber 101 and the network cable 103 is completed by the optical network terminal 100 with the optical module 200.

[0034] The optical interface of the optical module 200 is connected to the optical fiber 101, establishing a bidirectional optical signal connection with the optical fiber 101; the electrical interface of the optical module 200 is connected to the optical network terminal 100, establishing a bidirectional electrical signal connection with the optical network terminal 100; the optical module internally realizes bidirectional mutual conversion between optical signals and electrical signals, thereby realizing the establishment of an information connection between the optical fiber and the optical network terminal; specifically, the optical signal from the optical fiber 101 is converted into an electrical signal by the optical module and then input into the optical network terminal 100, and the electrical signal from the optical network terminal 100 is converted into an optical signal by the optical module and then input into the optical fiber 101.

[0035] The optical network terminal has an optical module interface 102 for connecting to the optical module 200 and establishing a bidirectional electrical signal connection with it. It also has a network cable interface 104 for connecting to the network cable 103 and establishing a bidirectional electrical signal connection (generally an Ethernet protocol signal, a different protocol / type from the signal used by the optical module). The optical module 200 and network cable 103 are connected via the optical network terminal 100. Specifically, the optical network terminal transmits signals from the optical module to the network cable and vice versa. The optical network terminal acts as a host computer for the optical module, monitoring its operation. The optical network terminal, acting as the host computer for the optical module, provides data signals to and receives data signals from it. Thus, the remote server establishes a bidirectional signal transmission channel with the local information processing equipment via optical fiber, optical module, optical network terminal, and network cable.

[0036] Common local information processing devices include routers, home switches, and computers; common optical network terminals include optical network units (ONUs), optical line terminals (OLTs), data center servers, and data center switches.

[0037] Figure 2 This is a schematic diagram of an optical network terminal structure. (Example:) Figure 2 As shown, the optical network terminal 100 has a circuit board 105, and a cage 106 is provided on the surface of the circuit board 105; an electrical connector is provided inside the cage 106 for connecting to the electrical interface (such as gold fingers) of the optical module; a heat sink 107 is provided on the cage 106, and the heat sink 107 has fins and other protrusions to increase the heat dissipation area.

[0038] The optical module 200 is inserted into the optical network terminal, the electrical interface of the optical module is inserted into the electrical connector inside the cage 106, and the optical interface of the optical module is connected to the optical fiber 101.

[0039] The cage 106 is located on the circuit board and encloses the electrical connectors on the circuit board inside the cage, thus providing electrical connectors inside the cage; the optical module is inserted into the cage and fixed by the cage, and the heat generated by the optical module is conducted to the cage 106 and then diffused through the heat sink 107 on the cage.

[0040] Figure 3 This is a schematic diagram of an optical module structure provided in an embodiment of this application. Figure 4 This is a schematic diagram of the exploded structure of an optical module provided in an embodiment of this application. Figure 5 This is an exploded view of the lens assembly and circuit board provided in an embodiment of this application. Figure 6 This is an exploded view of the fiber optic array, fiber optic connector, lens assembly, and circuit board provided in an embodiment of this application. Figure 3-6 As shown, the optical module 200 provided in this application embodiment includes an upper housing 201, a lower housing 202, an unlocking component 203, a circuit board 300, a lens assembly 400, an optical fiber array 500, and an optical fiber plug 600.

[0041] The upper housing 201 covers the lower housing 202 to form a wrapping cavity with two openings. The outer contour of the wrapping cavity is generally square. Specifically, the lower housing includes a main board and two side plates located on both sides of the main board and perpendicular to the main board. The upper housing includes a cover plate, which covers the two side plates of the upper housing to form the wrapping cavity. The upper housing may also include two side walls located on both sides of the cover plate and perpendicular to the cover plate. The two side walls are combined with the two side plates to realize that the upper housing covers the lower housing.

[0042] The two openings can be two openings (204, 205) located at the same end of the optical module, or two openings at different ends of the optical module; one of the openings is the electrical interface 204, from which the gold fingers of the circuit board extend and are inserted into the host computer such as the optical network terminal; the other opening is the optical interface 205, where the fiber optic adapter inside the optical module is located for connection with the external fiber optic connector (external fiber); the circuit board 300, lens assembly 400, fiber array 500 and fiber optic plug 600 and other optoelectronic devices are located in the encapsulated cavity.

[0043] The assembly method of combining the upper and lower shells facilitates the installation of components such as the circuit board 300, lens assembly 400, fiber array 500, and fiber plug 600 into the shell. The upper and lower shells form the outermost protective enclosure of the optical module. The upper and lower shells are generally made of metal materials, which is beneficial for electromagnetic shielding and heat dissipation. The shell of the optical module is generally not made into a single component, as a single shell is not conducive to the assembly of internal components.

[0044] The unlocking component 203 is located on the outer wall of the enclosing cavity / lower housing 202 and is used to realize the fixed connection between the optical module and the host computer, or to release the fixed connection between the optical module and the host computer.

[0045] The unlocking component 203 has a locking component that matches the host computer cage; pulling the end of the unlocking component allows the unlocking component to move relative to the surface of the outer wall; the optical module is inserted into the host computer cage, and the locking component of the unlocking component fixes the optical module in the host computer cage; by pulling the unlocking component, the locking component of the unlocking component moves accordingly, thereby changing the connection relationship between the locking component and the host computer, so as to release the locking relationship between the optical module and the host computer, thereby allowing the optical module to be pulled out of the host computer cage.

[0046] The circuit board 300 is equipped with an optical transmitter chip LD, a driver chip LDD, an optical receiver chip PD, a transimpedance amplifier chip TIA, a limiting amplifier chip LA, and a microprocessor chip MCU. The optical transmitter chip and the optical receiver chip are directly mounted on the circuit board of the optical module. This form is known in the industry as COB (chip on board) packaging.

[0047] The circuit board connects the electrical components in the optical module according to the circuit design through circuit traces to realize electrical functions such as power supply, electrical signal transmission and grounding.

[0048] Circuit boards are generally rigid circuit boards. Due to their relatively rigid material, rigid circuit boards can also perform load-bearing functions, such as stably supporting chips; when lens assemblies are located on the circuit board, rigid circuit boards can also provide stable support; rigid circuit boards can also be inserted into electrical connectors in the host computer cage. Specifically, metal pins / gold fingers are formed on one end surface of the rigid circuit board for connection with electrical connectors; these are features that flexible circuit boards cannot easily achieve. The most common type of rigid circuit board is a printed circuit board (PCB).

[0049] Optical modules sometimes use flexible circuit boards as a supplement to rigid circuit boards; flexible circuit boards are generally used in conjunction with rigid circuit boards.

[0050] The lens assembly 400 is mounted on the circuit board 300, covering the optical chip (the optical chip mainly refers to the light emitting chip, driver chip, light receiving chip, transimpedance amplifier chip, limiting amplifier chip, and other chips related to photoelectric conversion) in a snap-on manner. The lens assembly 400 and the circuit board 300 form a cavity encapsulating the light emitting chip, light receiving chip, and other optical chips, together forming a structure for encapsulating the optical chip. Light emitted from the light emitting chip is reflected by the lens assembly 400 and enters the fiber array 500. Light from the fiber array 500 is reflected by the lens assembly 400 and enters the light receiving chip. The lens assembly establishes an optical connection between the light emitting chip and the fiber array. The lens assembly not only seals the optical chip but also establishes an optical connection between the optical chip and the fiber array.

[0051] The lens assembly 400 can be integrally molded from polymer material using an injection molding process. Specifically, the material used to manufacture the lens assembly 400 includes materials with good light transmittance, such as PEI (Polyetherimide) plastic (Ultem series). Since all beam propagation elements in the lens assembly 400 are formed from a single piece of the same polymer material, the number of molding molds can be greatly reduced, lowering manufacturing costs and complexity. Furthermore, based on the lens assembly 400 structure described above, the embodiments of this application only require adjustment of the incident beam and the position of the optical fiber, simplifying installation and debugging.

[0052] One end of the fiber optic array 500 establishes an optical connection with the lens assembly 400, and the other end establishes an optical connection with the fiber optic adapter. The fiber optic array consists of multiple optical fibers. It transmits light from the lens assembly to the fiber optic adapter for emitting optical signals, and transmits light from the fiber optic adapter to the lens assembly for receiving optical signals from outside the optical module. The fiber optic array and lens assembly have a well-designed optical coupling structure. Multiple beams from the lens assembly are incident on the multiple optical fibers of the fiber optic array, and the optical structure of the lens assembly enables optical connection with the optical emitting chip; similarly, multiple beams from the fiber optic array are incident on the lens assembly, and the optical structure of the lens assembly enables optical connection with the optical receiving chip. The fiber optic array and lens assembly also have a well-designed fixing structure, allowing for relative fixation between them, thus ensuring that the lens assembly and the circuit board are relatively fixed, and the fiber optic array and the lens assembly are relatively fixed.

[0053] The fiber optic plug 600 connects to the fiber optic array 500 at one end and is inserted into the lens assembly 400 at the other end, for connecting the lens assembly 400 and the fiber optic array 500.

[0054] The fiber optic adapter, located at the optical interface formed by the upper and lower housings, is the connector that links the optical module to the external fiber optic connector (fiber). Furthermore, to achieve connection with the external fiber optic connector, matching structures are often required at the optical interface on the upper and lower housings. Fiber optic adapters generally have a standard shape and size for easy insertion of external fiber optic connectors / plugs. Internally, they have multiple fiber optic interfaces, including interfaces for transmitting and receiving optical signals. Common fiber optic connectors / plugs are MT-type fiber optic connectors (such as MPO (Multi-fiber Push On) fiber optic patch cord connectors). By inserting the fiber optic adapter into the optical module through the fiber optic connector, optical signals from inside the optical module can be transmitted to the external fiber optic cable, and vice versa.

[0055] Figure 7 This is an exploded view of the lens assembly and circuit board provided in an embodiment of this application from another angle. Figure 8 This is a schematic diagram of the lens assembly provided in an embodiment of this application. Figure 9 This is a first-part cross-sectional view of the lens assembly and circuit board provided in an embodiment of this application. Figure 7-9 As shown in the embodiment of this application, the lens assembly 400 includes a fixing member 401. Specifically,

[0056] The fastener 401 has a first sidewall 4011 and a first bottom surface 4012, that is, the inner surface of the fastener 401 is recessed to form the first sidewall 4011 and the first bottom surface 4012, and the outer surface is connected to the fiber optic plug 600.

[0057] Two first sidewalls 4011 are located on either side of the first bottom surface 4012. Adhesive is applied to the outer side of each sidewall, and a first adhesive groove 4013 is provided between the inner sidewall and the first bottom surface 4012. During use, the two first sidewalls 4011 are bonded to the surface of the circuit board 300. Because the first bottom surface 4012 is more recessed than the two first sidewalls 4011, a gap still exists between the first bottom surface 4012 and the surface of the circuit board 300 when the two first sidewalls 4011 are bonded to the surface of the circuit board 300.

[0058] In traditional optical modules, the two first sidewalls of the lens assembly are directly connected to the first bottom surface. When adhesive is applied to the outer sides of the two first sidewalls of the lens assembly, the adhesive seeps into the first bottom surface of the lens assembly along the gap between the circuit board and the first sidewalls due to capillary action, thereby affecting the various components within the lens assembly. In this embodiment, a first adhesive-separating groove 4013 is provided between the inner sides of the two first sidewalls 4011 and the first bottom surface 4012.

[0059] The first adhesive-separating groove 4013 is provided to prevent adhesive from seeping into the first bottom surface 4012. Specifically, the first adhesive-separating groove 4013 not only thins the first sidewall 4011 but also partially separates the first sidewall 4011 from the first bottom surface 4012. Thinning the first sidewall 4011 reduces the capillary action between the first sidewall 4011 and the circuit board 300, thus reducing the amount of adhesive seeping into the lens assembly 400. Due to the first adhesive-separating groove 4013, when adhesive enters the lens assembly 400 via capillary action, the adhesive enters the first adhesive-separating groove 4013, preventing it from seeping into the first bottom surface 4012.

[0060] When a large amount of adhesive seeps into the lens assembly 400, in order to further prevent the adhesive from seeping into the first bottom surface 4012, the depth of the first adhesive septum 4013 can be greater than or equal to 0.5 mm.

[0061] Ejector pins are plastic mold components used in plastic molds to separate products from the mold. Therefore, the inner surface of the lens assembly after production has ejector pin holes for housing ejector pins, and these holes are directly connected to the first bottom surface. When some glue enters the ejector pin holes, it may bypass the holes and enter the first bottom surface, potentially affecting the components within the lens assembly. To further prevent glue from entering the first bottom surface, in this embodiment, a second adhesive separation groove 4014 and a third adhesive separation groove 4015 are also provided between the inner sides of the two first sidewalls 4011 and the first bottom surface 4012. Specifically,

[0062] The second and third adhesive-separating grooves 4014 and 4015 are located at opposite ends of the first adhesive-separating groove 4013, respectively, and are used to house the pin holes to further prevent adhesive from seeping into the first bottom surface 4012. Specifically, because the second and third adhesive-separating grooves 4014 and 4015 are more recessed than the first sidewall 4011 and the first bottom surface 4012, their arrangement not only further thins the first sidewall 4011 but also further separates it from the first bottom surface 4012. When adhesive seeps into the lens assembly 400, it will enter not only the first adhesive-separating groove 4013 but also the second and third adhesive-separating grooves 4014 and 4015, further preventing adhesive from seeping into the first bottom surface 4012.

[0063] The design of the first adhesive septum 4013, the second adhesive septum 4014, and the third adhesive septum 4015 effectively thins the first sidewall 4011 and separates it from the first bottom surface 4012. Thinning the first sidewall 4011 reduces capillary action and decreases the amount of adhesive that seeps into the lens assembly 400. Separating the first sidewall 4011 from the first bottom surface 4012 allows adhesive that has seeped into the lens assembly 400 to enter the first adhesive septum 4013, the second adhesive septum 4014, and the third adhesive septum 4015, making it less likely for it to enter the first bottom surface 4012.

[0064] Adhesive will only enter the first bottom surface 4012 if the amount of adhesive is sufficient to pass through the first adhesive separation groove 4013, the second adhesive separation groove 4014, and the third adhesive separation groove 4015. To further reduce adhesive entering the first bottom surface 4012, in this embodiment, the first adhesive separation groove 4013 is more recessed than the second adhesive separation groove 4014 and the third adhesive separation groove 4015. Since the depth of the first adhesive separation groove is greater than or equal to 0.5 mm, the depths of the second adhesive separation groove 4014 and the third adhesive separation groove 4015 are both greater than or equal to 0.25 mm. To further reduce adhesive passing through the first adhesive separation groove 4013, the second adhesive separation groove 4014, and the third adhesive separation groove 4015, in this embodiment, the widths of the second adhesive separation groove 4014 and the third adhesive separation groove 4015 are both greater than or equal to 0.5 mm.

[0065] To further reduce the amount of adhesive entering the first bottom surface 4012, in this embodiment, the size of the ejector pin hole placed in the second adhesive septum 4014 and the third adhesive septum 4015 can be reduced. When the ejector pin hole is reduced, the amount of adhesive that can be placed in the second adhesive septum 4014 and the third adhesive septum 4015 increases, sufficient to increase the amount of adhesive that passes through the second adhesive septum 4014 and the third adhesive septum 4015.

[0066] The ejector pin holes in the second and third septum grooves 4014 and 4015 can be of equal or unequal size. When the ejector pin hole in the second septum groove 4014 is larger than the ejector pin hole in the third septum groove 4015, the width of the second septum groove 4014 is generally greater than or equal to the width of the third septum groove 4015. When the ejector pin hole in the second septum groove 4014 is less than or equal to the ejector pin hole in the third septum groove 4015, the width of the second septum groove 4014 is generally less than or equal to the width of the third septum groove 4015. However, there are exceptions. For example, when the ejector pin hole in the second septum groove 4014 is less than or equal to the ejector pin hole in the third septum groove 4015, the width of the second septum groove 4014 is generally greater than or equal to the width of the third septum groove 4015. All of the above situations are possible, as long as the second and third septum grooves 4014 and 4015 can accommodate the corresponding ejector pin holes. This application is not restrictive and can be designed according to specific circumstances.

[0067] The above describes the situation where the adhesive dispensing location is on the outside of the first sidewall 4011. When the adhesive dispensing location is on the outside of the second sidewall 4021, the specific description is as follows:

[0068] Figure 10 This is a second cross-sectional view of the lens assembly and circuit board provided in an embodiment of this application. Figure 11 This is a third cross-sectional view of the lens assembly and circuit board provided in an embodiment of this application. Figure 7 , 8 As shown in Figures 10 and 11, in this embodiment of the application, the lens assembly 400 further includes a cover cavity 402. Specifically,

[0069] The covering cavity 402 has a second sidewall 4021, a second bottom surface 4023, and a third sidewall 4022. Specifically, the second sidewall 4021, the second bottom surface 4023, and two third sidewalls 4022 are recessed on the inner surface of the covering cavity 402. The covering cavity 402 covers the optical chip. Specifically, the two third sidewalls 4022 are located on both sides of the second bottom surface 4023, with one end connected to both ends of the second sidewall 4021, forming a covering cavity 402.

[0070] In traditional optical modules, the second sidewall and two third sidewalls of the lens assembly are directly connected to the second bottom surface. When adhesive is applied to the outside of the second sidewall and two third sidewalls of the lens assembly, the adhesive seeps into the first bottom surface of the lens assembly along the gap between the circuit board and the second and third sidewalls due to capillary action, thereby affecting the various components inside the lens assembly.

[0071] The second sidewall 4021 has a fourth sidewall 4024 that is more recessed than the second sidewall 4021 on the inner side adjacent to the second bottom surface 4023. Specifically, the fourth sidewall 4024 effectively thins the second sidewall 4021. Thinning the second sidewall 4021 reduces capillary action between the second sidewall 4021 and the circuit board 300, resulting in a significant reduction in the amount of adhesive entering the lens assembly 400.

[0072] Since the optical chip is located near the second sidewall 4021, the presence of the fourth sidewall 4024 effectively increases the distance between the optical chip and the second sidewall 4021. Because the amount of adhesive is significantly reduced and the distance between the optical chip and the second sidewall 4021 is increased, the adhesive entering the lens assembly 400 will flow into the fourth sidewall 4024 and will not enter the second bottom surface 4023.

[0073] To further reduce the amount of adhesive entering the second bottom surface 4023, in this embodiment, a fifth sidewall 4025 is provided on the inner side of the third sidewall 4022 adjacent to the second bottom surface 4023. The fifth sidewall 4025 is more recessed than the third sidewall 4022. Specifically, the provision of the fifth sidewall 4025 is equivalent to thinning the third sidewall 4022. Thinning the third sidewall 4022 can reduce the capillary effect between the third sidewall 4022 and the circuit board 300, thereby significantly reducing the amount of adhesive entering the lens assembly 400.

[0074] In order to further reduce the amount of glue entering the second bottom surface 4023, in this embodiment of the application, each of the two third sidewalls 4022 is provided with a fifth sidewall 4025 that is more recessed than the third sidewall 4022 on the side (inner side) adjacent to the second bottom surface 4023.

[0075] As can be seen from the configuration of the fourth sidewall 4024, the configuration of the fifth sidewall 4025 and the fourth sidewall 4024 are both to thin the sidewall of the cover cavity 402, reduce the capillary phenomenon between the cover cavity 402 and the circuit board 300, and thus significantly reduce the amount of adhesive entering the lens assembly 400.

[0076] To further reduce capillary action between the enclosure cavity 402 and the circuit board 300, in this embodiment, the thickness of the fourth sidewall 4024 is greater than half the thickness of the second sidewall 4021, the thickness of the fifth sidewall 4025 is greater than half the thickness of the third sidewall 4022, and the depth of the fourth sidewall 4024 is less than half the depth of the second sidewall 4021.

[0077] like Figure 8 As shown, the lens assembly 400 also has a vent 4026. This vent 4026 is located on the second bottom surface 4023 and is used for ventilation of the adhesive inside the lens assembly 400. When the vent 4026 of the lens assembly 400 is not located on the second bottom surface 4023, it can also be located on the first sidewall 4011.

[0078] This application provides an optical module, including a circuit board, an optical chip disposed on the circuit board, and a lens assembly connected to the circuit board. The optical chip is used to generate or receive optical signals. The lens assembly, covering the optical chip, is used to change the propagation direction of the optical signal. The lens assembly includes a fixing member. The surface of the fixing member is recessed to form a first sidewall and a first bottom surface. Adhesive is applied to the outer side of the first sidewall, and a first adhesive-separating groove is provided between the inner side of the first sidewall and the first bottom surface. The first adhesive-separating groove is more recessed than the first sidewall and the first bottom surface, and is used to prevent adhesive from entering the first bottom surface of the lens assembly. The provision of the first adhesive-separating groove is equivalent to thinning the first sidewall, reducing the capillary effect between the first sidewall and the circuit board, and preventing adhesive that crosses the first sidewall from seeping into the first bottom surface of the lens assembly. In this application, the inner surface of the fixing member of the lens assembly is provided with a first adhesive septum. The first adhesive septum is located between the first sidewall and the first bottom surface, and the first adhesive septum is more concave than the first sidewall and the first bottom surface. When the adhesive passes over the first sidewall, it can enter the first adhesive septum, thus preventing the adhesive from entering the first bottom surface of the lens assembly and thus preventing contamination of the various components inside the lens assembly.

[0079] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. An optical module, characterized in that, include: Circuit board; An optical chip, disposed on the circuit board, is used to generate or receive optical signals; A lens assembly, connected to the circuit board, covers the optical chip and is used to change the propagation direction of the optical signal; The lens assembly includes a cover cavity and a fixing component; The covering cavity has a second sidewall, a second bottom surface and a third sidewall, and covers the optical chip; The second sidewall has a fourth sidewall on the side adjacent to the second bottom surface; the fourth sidewall is more recessed than the second sidewall. The third sidewall is located on one side of the second bottom surface, with one end connected to one end of the second sidewall, and a fifth sidewall is provided on the side adjacent to the second bottom surface; the fifth sidewall is more recessed than the third sidewall. The cover cavity has a vent hole for the adhesive inside the lens assembly to allow air to pass through. The fastener has a first sidewall and a first bottom surface; A second adhesive septum and a third adhesive septum are provided between the inner sides of both first sidewalls and the first bottom surface; the second adhesive septum and the third adhesive septum are both used to place the pin hole.

2. The optical module according to claim 1, characterized in that, Adhesive is applied to the outer side of the first sidewall, and a first adhesive septum is provided between the inner side of the first sidewall and the first bottom surface. The first adhesive-separating groove has a second adhesive-separating groove and a third adhesive-separating groove at each end, which are more recessed relative to the first sidewall and the first bottom surface, and are used to prevent adhesive from entering the first bottom surface of the lens assembly.

3. The optical module according to claim 2, characterized in that, The first diaphragm groove is more recessed than the second and third diaphragm grooves.

4. The optical module according to claim 1, characterized in that, The thickness of the fourth sidewall is greater than half the thickness of the second sidewall, and the depth of the fourth sidewall is less than half the depth of the second sidewall.

5. The optical module according to claim 1, characterized in that, The thickness of the fifth sidewall is greater than or equal to half the thickness of the third sidewall.

6. The optical module according to claim 2, characterized in that, The two first sidewalls are located at opposite ends of the first bottom surface, and adhesive is applied to their outer sides.

7. The optical module according to claim 2, characterized in that, The depth of the first separator groove is greater than or equal to 0.5 mm, the depth of the second separator groove and the third separator groove are both greater than or equal to 0.25 mm, and the width of the second separator groove and the third separator groove are both greater than or equal to 0.5 mm.

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