CN217034337U - Optical module - Google Patents

Abstract

The optical module comprises a shell, wherein a laser chip is arranged in the shell, a first opening is formed in the side wall of the shell, a circuit board extends into the shell through the first opening, a laser driving chip is arranged outside the shell, and a gap is formed between the bottom end of a top plate of the first opening and the circuit board; high frequency signal line passes first opening and laser chip electricity from laser driver chip and is connected, lead to high frequency signal line part can be covered by the casing lateral wall, high frequency signal line is slightly little by the impedance of casing lateral wall coverage area in the original design, this application is through reducing the linewidth of high frequency signal line by the cavity lateral wall coverage area, thereby reduce this regional unit length electric capacity, increase this regional impedance, and then increase the impedance continuity of high frequency signal line self, thereby optimize the high frequency performance of high frequency signal line.

Description

Optical module

Technical Field

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

Background

The optical module realizes the function of photoelectric conversion in the technical field of optical fiber communication, and the intensity of an optical signal input into an external optical fiber by the optical module directly influences the quality of optical fiber communication. The light emitting part of the optical module is packaged by micro-optical form, namely, the light emitted by the optical chip enters the air, and the light emitted by the optical chip is coupled into the optical fiber adapter after passing through the lens during the period that the lens, the optical fiber adapter and the like are arranged on an optical path, and the optical fiber adapter is connected with the optical fiber.

In an optical module packaged in a micro-optical form, a metal shell is generally adopted to protect key devices such as a laser chip, high-frequency signal lines of the devices such as the laser chip are often located on the surface of a circuit board, the upper part of the partial area of the high-frequency signal lines can be covered by the metal shell, in order to avoid the short circuit phenomenon between the metal shell and the high-frequency signal lines, a certain gap needs to be arranged between the metal shell and the high-frequency signal lines, the high-frequency signal lines are made of metal materials, and a certain gap is arranged between the metal shell and the high-frequency signal lines, so that parasitic capacitance can be generated between the metal shell and the high-frequency signal lines, and the single-bit length capacitance of the area covered by the metal shell on the high-frequency signal lines is increased, so that the impedance of the area is reduced, and the impedance of the high-frequency signal lines at the position is discontinuous.

SUMMERY OF THE UTILITY MODEL

The application provides an optical module to reduce the influence of a metal shell on the impedance continuity of a high-frequency signal line.

The application provides an optical module, includes:

the surface of the circuit board is respectively provided with a laser driving chip and a high-frequency signal line, and one end of the high-frequency signal line is electrically connected with the laser driving chip;

a light emitting assembly electrically connected to the circuit board for converting an electrical signal to an optical signal, comprising:

the circuit board extends into the shell through the first opening, a laser chip is arranged in the shell, and the other end of the high-frequency signal line penetrates through the first opening and is electrically connected with the laser chip;

the laser chip is arranged in the shell, the laser driving chip is arranged outside the shell, a first gap is formed between the bottom end of the top plate of the first opening and the upper surface of the circuit board, the upper surface of the first gap is the bottom end of the top plate of the first opening, and the lower surface of the first gap is the high-frequency signal line;

the line width of the area covered by the first side wall in the high-frequency signal line is smaller than the line width of the rest area in the high-frequency signal.

The optical module provided by the embodiment of the application comprises a shell, wherein a laser chip is arranged in the shell, a first opening is formed in the side wall of the shell, a circuit board extends into the shell through the first opening, a laser driving chip is arranged outside the shell, and a gap is formed between the bottom end of a top plate of the first opening and the circuit board; the high-frequency signal line penetrates through the first opening from the laser driving chip and is electrically connected with the laser chip, so that the high-frequency signal line is partially covered by the side wall of the shell, the impedance of an area, covered by the side wall of the shell, of the high-frequency signal line in the original design is low, the line width of the area, covered by the side wall of the cavity, of the high-frequency signal line is reduced, the unit length capacitance of the area is reduced, the impedance of the area is increased, the impedance continuity of the high-frequency signal line is further increased, and the high-frequency performance of the high-frequency signal line is optimized; therefore, the local line width of the high-frequency signal line is narrowed, so that the impedance continuity of the high-frequency signal line is improved, and the high-frequency performance of the high-frequency signal line is optimized.

Drawings

In order to more clearly illustrate the technical solutions in the present disclosure, the drawings needed to be used in some embodiments of the present disclosure will be briefly described below, and it is apparent that the drawings in the following description are only drawings of some embodiments of the present disclosure, and other drawings can be obtained by those skilled in the art according to the drawings. Furthermore, the drawings in the following description may be regarded as schematic diagrams, and do not limit the actual size of products, the actual flow of methods, the actual timing of signals, and the like, involved in the embodiments of the present disclosure.

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

FIG. 2 is a block diagram of an optical network terminal according to some embodiments;

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

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

FIG. 5 is a schematic diagram of structures on a circuit board of an optical module according to some embodiments;

FIG. 6 is an internal schematic view of a light emitting assembly on a circuit board of a light module according to some embodiments;

FIG. 7 is an exploded view of a housing and circuit board of an optical module according to some embodiments;

FIG. 8 is a detailed block diagram of a housing of a light module according to some embodiments;

FIG. 9 is a detailed block diagram of a housing of a light module according to some embodiments;

FIG. 10 is a detailed block diagram of a housing of a light module according to some embodiments;

FIG. 11 is an assembly view of a housing and circuit board of an optical module according to some embodiments;

FIG. 12 is an assembly view of a housing and circuit board of an optical module according to some embodiments;

FIG. 13 is an assembled detail view of a housing and circuit board of an optical module according to some embodiments;

fig. 14 is an electrical connection diagram of a laser chip and a laser driving chip of an optical module according to some embodiments;

fig. 15 is a schematic diagram illustrating a relative relationship between a housing of an optical module and a high-frequency signal line according to some embodiments;

fig. 16 is a schematic structural diagram of a high-frequency signal line between a laser chip and a laser driving chip of an optical module according to some embodiments.

Detailed Description

In the field of optical fiber communication technology, signals transmitted by information transmission devices such as optical fibers or optical waveguides are optical signals, while signals that can be recognized and processed by information processing devices such as computers are electrical signals, so that the optical signals and the electrical signals need to be converted into each other by using optical modules.

Fig. 1 is a connection diagram of an optical communication system according to some embodiments. As shown in fig. 1, a bidirectional optical communication system is established between a remote server 1000 and a local information processing device 2000 through an optical fiber 101, an optical module 200, an optical network terminal 100, and a network cable 103.

One end of the optical fiber 101 is connected to the remote server 1000, and the other end is connected to the optical network terminal 100 through the optical module 200. One end of the network cable 103 is connected to the local information processing device 2000, and the other end is connected to the optical network terminal 100.

The connection between the local information processing device 2000 and the remote server 1000 is completed by the optical fiber 101 and the network cable 103; and the connection between the optical fiber 101 and the network cable 103 is completed by the optical module 200 and the optical network terminal 100.

In the optical module 200, an optical port is configured to be connected with the optical fiber 101, so that the optical module 200 establishes a bidirectional optical signal connection with the optical fiber 101; the electrical port is configured to be plugged into the optical network terminal 100 so that the optical module 200 establishes a bi-directional electrical signal connection with the optical network terminal 100. The optical module 200 converts an optical signal and an electrical signal to each other, so that the optical fiber 101 and the optical network terminal 100 are connected to each other.

The optical network terminal 100 is provided with an optical module interface 102 and a network cable interface 104. The optical module interface 102 is configured to access the optical module 200, so that the ont 100 establishes a bidirectional electrical signal connection with the optical module 200; the network cable interface 104 is configured to access the network cable 103 such that the optical network terminal 100 establishes a bi-directional electrical signal connection with the network cable 103. The optical module 200 is connected to the network cable 103 via the optical network terminal 100. The upper computer of the Optical module 200 may include an Optical Line Terminal (OLT) in addition to the Optical network Terminal 100.

Fig. 2 is a block diagram of an optical network terminal according to some embodiments, and as shown in fig. 2, the optical network terminal 100 further includes a PCB circuit board 105 disposed in the housing, a cage 106 disposed on a surface of the PCB circuit board 105, and an electrical connector disposed inside the cage 106. The electrical connector is configured to access an electrical port of the optical module 200; the heat sink 107 has a projection such as a fin that increases a heat radiation area.

The optical module 200 is inserted into a cage 106 of the onu 100, the cage 106 holds the optical module 200, and heat generated by the optical module 200 is conducted to the cage 106 and then diffused by a heat sink 107. After the optical module 200 is inserted into the cage 106, an electrical port of the optical module 200 is connected to an electrical connector inside the cage 106, and the optical module 200 establishes a bidirectional electrical signal connection with the onu 100.

Fig. 3 is a block diagram of a light module according to some embodiments, and fig. 4 is an exploded view of a light module according to some embodiments. As shown in fig. 3 and 4, the optical module 200 includes a housing, a circuit board 105 disposed in the housing;

the shell comprises an upper shell 201 and a lower shell 202, wherein the upper shell 201 is covered on the lower shell 202 to form the shell with two openings 204 and 205; the outer contour of the housing generally appears square.

The direction of the connecting line of the two openings 204 and 205 may be the same as the length direction of the optical module 200, or may not be the same as the length direction of the optical module 200. Wherein, the opening 204 is an electric port, and the golden finger of the circuit board 105 extends out of the opening 204 and is inserted into the upper computer; the opening 205 is an optical port, and is configured to receive an external optical fiber 101 so that the optical fiber 101 is connected to the inside of the optical module 200.

The upper shell 201 and the lower shell 202 are combined in an assembly mode, so that the devices such as the circuit board 105 and the like can be conveniently installed in the shells, and the upper shell 201 and the lower shell 202 can form packaging protection for the devices. In some embodiments, the upper housing 201 and the lower housing 202 are generally made of a metal material, which is beneficial to achieve electromagnetic shielding and heat dissipation.

In some embodiments, the light module 200 further comprises an unlocking member 203 located on an outer wall of its housing. When the optical module 200 is inserted into the cage of the upper computer, the optical module 200 is clamped in the cage of the upper computer by the clamping component of the unlocking component 203; when the unlocking member 203 is pulled, the engaging member of the unlocking member 203 moves along with the unlocking member, and the connection relationship between the engaging member and the upper computer is changed, so that the engagement between the optical module 200 and the upper computer is released.

The circuit board 105 includes circuit traces, electronic components, and chips, and the electronic components and the chips are connected together by the circuit traces according to a circuit design.

The circuit board 105 is generally a rigid circuit board, which can also perform a bearing function due to its relatively rigid material, for example, the rigid circuit board can stably bear a chip; the rigid circuit board can also be inserted into an electric connector in the cage of the upper computer.

The circuit board 105 further includes a gold finger formed on an end surface thereof, the gold finger being composed of a plurality of leads independent of each other. The circuit board 105 is inserted into the cage 106, and electrically connected to an electrical connector in the cage 106 by gold fingers. The golden finger 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, the flexible circuit board may be used with the circuit board 105 in some optical modules.

As shown in fig. 5, the optical transceiver module includes an optical transmitter module 300 and an optical receiver module 400; in the present application, the light emitting module 300 and the light receiving module 400 are packaged in micro-optics, that is, light emitted by the optical chip enters air, and during the period of setting the lens and the optical fiber adapter on the optical path, the light emitted by the optical chip is coupled to the optical fiber adapter through the lens, and the optical fiber adapter is connected with the optical fiber. The packaging form and the packaging structure of the light emitting component 300 and the light receiving component 400 are not particularly limited in the present application, and the technical solutions provided in the embodiments of the present application can be applied to the other packaging forms and packaging structures in the same adaptability; the light emitting module 300 converts the received electrical signal into an optical signal, and the light receiving module 400 converts the received optical signal into an electrical signal, thereby implementing a photoelectric conversion function of the optical module. The specific arrangement of the light emitting element 300 and the light receiving element 400 on the circuit board 105 can refer to fig. 5; the light emitting module 300 is located at the edge of the circuit board 105, and the light emitting module 300 and the light receiving module 400 are arranged on the surface of the circuit board 105 in a staggered manner, so that a better electromagnetic shielding effect is favorably realized. The circuit board 105 is provided with a notch for placing the light emitting component 300, and the notch can be arranged in the middle of the circuit board 105 or at the edge of the circuit board 105; the light emitting assembly 300 is disposed in the gap by embedding, so that the circuit board can be conveniently inserted into the light emitting assembly 300, and the light emitting assembly and the circuit board can be conveniently fixed together. The light receiving module 400 is disposed on the surface of the circuit board 105, and in another common packaging method, the light receiving module is physically separated from the circuit board, and is electrically connected through a flexible circuit board.

As shown in fig. 6, the light emitting module 300 according to the embodiment of the present disclosure includes a cover plate (not shown) and a housing 310, the housing 310 is covered by the cover plate from above, a notch 1051 is disposed near an edge of the circuit board 105 for embedding the housing 310; a side wall of the housing 310 has an opening for inserting the circuit board 105, and the circuit board 105 is fixed with the lower housing of the optical module; the laser chip 320 is arranged in the shell 310, the circuit board 105 extending into the shell 310 is electrically connected with the laser chip 320, and the laser chip 320 is used for converting an electric signal into an optical signal; the other side wall of the housing 310 has a through hole, and the optical signal generated by the laser chip 320 is emitted into the through hole and then emitted to the outside of the optical module. The circuit board 105 is also provided with a laser driving chip 1052, and the surface of the circuit board 105 is provided with a driving pad to arrange the laser driving chip 1052. As shown in fig. 8, the laser driver chip 1052 includes a positive modulation current output terminal, a negative modulation current output terminal, and a bias current output terminal, and accordingly, the laser driver chip 1052 is provided with a positive modulation current output pin, a negative modulation current output pin, and a bias current output pin to output a positive modulation current, a negative modulation current, and a bias current to the laser, respectively, and the positive modulation current and the negative modulation current provide a high frequency signal for the laser; the bias current drives the laser to emit light, and a high-frequency signal is modulated into a light beam generated by the laser to generate signal light.

Specifically, as shown in fig. 7, in order to connect the housing 310 and the circuit board 105, a notch 1051 is disposed at an edge of the circuit board 105, the housing 310 is disposed in the notch 1051, specifically, a part of the structure of the housing 310 is embedded in the notch 1051, so as to embed the housing 310 in the notch 1051, another sidewall of the housing 310 has a through hole 314, and an optical signal generated by the laser chip 320 is incident into the through hole 314 and then emitted to the outside of the optical module; the optical signal generated by the laser chip 320 is emitted through the through hole 314, and in order to avoid the optical signal from being affected by other structures and signal lines on the surface of the circuit board 105, the notch 1051 is set to have the following dimensions: the size of the notch 1051 is larger than that of the housing 310, and there is a blank area in the notch 1051 except for the area where the housing 310 is disposed, so as to stabilize the optical signal generated by the laser chip 320.

In order to make the connection between the housing 310 and the circuit board 105 more secure and reliable, the three side walls of the housing 310 are respectively provided with openings for the circuit board 105 to extend into the housing 310, and through the openings of the three side walls, the housing 310 is partially embedded in the notch 1051, and partially disposed on the upper surface of the circuit board 105, so that the circuit board 105 can both carry the housing 310 and make the housing 310 extend downward into the circuit board 105, specifically, one side of the housing 310 close to the laser driver chip 1052 is hollowed inward to form a first opening 311, and one side of the notch 1051 close to the laser driver chip 1052 extends into the first opening 311; two sides of the bottom end of the housing 310 are hollowed upwards and inwards respectively to form a second opening 312 and a third opening 313, and two relatively longer end parts of the notch 1051 extend into the second opening 312 and the third opening 313 respectively, so that the circuit board 105 extends into the housing 310 through the first opening 311, the second opening 312 and the third opening 313, and then an area formed in the middle of the second opening 312 and the third opening 313 is embedded into the notch 1051; the circuit board 105 partially extends into the housing 310 through the first opening 311, and partially extends out of the housing 310; the second opening 312 and the third opening 313 may be disposed to increase the firmness of the housing 310 being inserted into the notch 1051.

Fig. 8, 9 and 10 respectively show structural diagrams of the housing 310 at different angles, as shown in fig. 8, the housing 310 is respectively provided with a first opening 311, a second opening 312 and a third opening 313, and the circuit board 105 extends into the housing 310 through the first opening 311, the second opening 312 and the third opening 313; as shown in fig. 9, one end of the housing 310 close to the laser driver chip 1052 is provided with a first opening 311 for the notch 1051 to extend into, and one side perpendicular to the first opening 311 is provided with a second opening 312 for the notch 1051 to extend into; as shown in fig. 10, the first opening 311 includes a top plate and a bottom plate, the top plate has a length longer than that of the bottom plate, and a bottom end of the top plate is recessed upward to form a structure 3111, which is specifically described later; the housing 310 further includes a connection portion 315, and the connection portion 315 is a structure closest to the laser driving chip in the housing 310.

Fig. 11 illustrates an effect schematic diagram of disposing the housing 310 in the notch 1051 of the circuit board 105, as shown in fig. 11, three side ends of the notch 1051 respectively extend into the first opening 311, the second opening 312 and the third opening 313, and then a middle area formed in the second opening 312 and the third opening 313 is embedded in the notch 1051, so that the circuit board 105 extends into the housing 310, and the circuit board 105 and the housing 310 are connected; through the first opening 311, the second opening 312 and the third opening 313, the housing 310 is partially embedded in the notch 1051 and partially disposed on the upper surface of the circuit board 105, so that the circuit board 105 can carry the housing 310 and the housing 310 can extend downward into the circuit board 105, thereby increasing the connection reliability between the circuit board 105 and the housing 310.

In the embodiment of the present invention, a plurality of signal lines, especially high-frequency signal lines, are disposed on the surface of the circuit board 105, and in order to avoid short circuit of signals, a gap is disposed between the housing 310 and the high-frequency signal lines, and the two signal lines are isolated from each other, specifically, as shown in fig. 12 and 13, a first gap 3111 is disposed between the bottom end of the top plate of the first opening 311 and the upper surface of the circuit board 105, specifically, the bottom end of the top plate of the first opening 311 is recessed upwards to form a first gap 3111, under the action of the first gap 3111, the housing 310 is spaced from the upper surface of the circuit board 105, and specifically, a first gap 3111 is disposed between the connecting portion 315 in the sidewall of the housing 310 and the upper surface of the circuit board 105; as further shown in fig. 12 and 13, the longitudinal distance of the first opening 311 is greater than the thickness of the circuit board 105, wherein the longitudinal direction is defined as: in fig. 12, the direction of the circuit board 105 is the horizontal direction, and the direction perpendicular to the horizontal direction is the longitudinal direction; the longitudinal distance of the first opening 311 is greater than the thickness of the circuit board 105, a first gap 3111 is formed between the bottom end of the top plate of the first opening 311 and the circuit board 105, a second gap 3112 is formed between the lower surface of the circuit board 105 and the upper surface of the bottom plate of the first opening 311, and the first gap 3111 and the second gap 3112 can isolate the housing 310 from respective signal lines on the upper surface and the lower surface of the circuit board to avoid signal short circuit; it is understood that the size ranges of the first gap 3111 and the second gap 3112 are within the protection scope of the present application, and the present application does not limit the specific size of the second gap 3112 of the first gap 3111; since the closer the housing 310 is to the high-frequency signal line, the smaller the impedance of the region covered by the housing 310, in the present embodiment, when the size of the first gap 3111 is set to 0.85mm or more, the housing 310 has substantially no influence on the impedance continuity of the high-frequency signal line, and when the size of the first gap 3111 is set to 0.45 or less, the influence of the housing 310 on the impedance continuity of the high-frequency signal line is significant; the distance from the bottom end of the connection portion 315 to the high-frequency signal line 1053 is: when 0.85mm or more, the case 310 has substantially no influence on the impedance continuity of the high-frequency signal line, and when 0.45 mm or less, the case 310 has a significant influence on the impedance continuity of the high-frequency signal line.

The high-frequency signal line 1053 is arranged between the laser chip 320 and the laser driving chip 1052, and the high-frequency signal line 1053 is used for transmitting a driving signal generated by the laser driving chip 1052 to the laser chip 320 so as to drive the laser chip 320 to emit a light signal; in the present application, the high-frequency signal line 1053 between the laser chip 320 and the laser driver chip 1052 is taken as an example, and the high-frequency signal line may also include high-frequency signal lines between other optoelectronic devices; since the laser chip 320 is disposed inside the housing 310, the laser driver chip 1052 is disposed outside the housing 310, the high-frequency signal line 1053 is located on the surface of the circuit board 105, a part of the high-frequency signal line 1053 is located inside the housing 310, and a part of the high-frequency signal line 1053 is located outside the housing 310, and the high-frequency signal line 1053 passes through a part of the structure of the housing 310 from the laser driver chip 1052 and is connected to the laser chip, the high-frequency signal line therebetween is inevitably covered by the housing 310, specifically, one end of the high-frequency signal line 1053 is electrically connected to the laser driver chip 1052, and the other end of the high-frequency signal line 1053 is electrically connected to the laser chip 320 through the connecting portion 315; a region in which the high-frequency signal line 1053 exists is covered with the connection portion 315 in the cavity side wall; the housing 310 and the high-frequency signal line 1053 are both made of metal, and a first gap 3111 is formed between the connection portion 315 of the sidewall of the housing 310 and the upper surface of the circuit board 105, so that a parasitic capacitance is generated between the housing 310 and the high-frequency signal line 1053, the capacitance per unit length of the region covered by the sidewall of the housing 310 in the high-frequency signal line 1053 is increased, and the impedance is inversely proportional to the capacitance per unit length, so that the impedance of the region covered by the sidewall of the housing 310 in the high-frequency signal line 1053 is reduced, and the impedance of the region covered by the housing 310 in the high-frequency signal line 1053 is discontinuous from the impedance of the rest region. Fig. 14 is a schematic diagram of a high-frequency signal line 1053 between the laser chip 320 and the laser driver chip 1052.

In some embodiments of the present application, the larger the first gap 3111 is, the less the impedance continuity of the high-frequency signal line 1053 is affected by the housing 310, but when the first gap 3111 is larger, the hermeticity of the housing cannot be ensured, and when the hermeticity of the housing cannot be ensured, the laser chip inside the housing may be affected by moisture and the like outside the housing, so that the performance of the laser chip cannot be ensured; therefore, in order to ensure the airtightness of the housing 310, the first space 3111 is not necessarily too large, but when the first space 3111 is small, the housing 310 is located closer to the high-frequency signal line 1053, and the impedance continuity of the high-frequency signal line 1053 is affected by the housing 310, and for this purpose, as shown in fig. 15 and fig. 16, in the embodiment of the present application, in order to increase the impedance of the region of the high-frequency signal line 1053 covered by the side wall of the housing 310, the line width of the region of the high-frequency signal line 1053 covered by the side wall of the housing 310 is narrowed, that is, the line width of the region covered by the case 310 in the high-frequency signal line 1053 is smaller than the line width of the remaining region in the high-frequency signal line 1053, as shown in fig. 15, the high-frequency signal line 1053 includes a first line segment 10531, a second line segment 10532, and a third line segment 10533, wherein the line width of the second line segment 10532 is smaller than the line width of the first line segment 10531, the line width of the first line segment 10531 can be equal to the line width of the third line segment 10533; the second line segment 10532 is the region where the high-frequency signal line 1053 is covered by the sidewall of the housing 310, and the second line segment 10532 is specifically the projection region of the side end of the housing 310 close to the laser driving chip 1052 on the high-frequency signal line 1053; specifically, the second line segment 10532 is a region covered by the connecting portion 315 in the housing 310, in this embodiment, the line width of the region covered by the connecting portion 315 of the housing of the high-frequency signal line is narrowed, and then the capacitance per unit length of the region is reduced, so as to increase the impedance of the region, so as to compensate the influence of the housing on the impedance continuity of the high-frequency signal line; thereby improving signal integrity and optimizing high-frequency performance; in order to highlight the advantages of the technical solution in the present application, in the embodiment of the present application, the width of the connection portion 315 and the length of the second line segment 10532 are set to be the same, that is, the area covered by the connection portion 315 in the high-frequency signal line 1053 is precisely designed as a narrow area with a line width, and the connection portion 315 is projected from top to bottom to just coincide with the length area of the second line segment 10532; in the embodiment of the application, the line width of the high-frequency signal line in the area covered by the shell is narrowed, the unit-length capacitance of the area is reduced to be offset with the parasitic capacitance generated between the shell and the high-frequency signal line, so that the impedance of the area is increased, the influence of the shell on the continuity of the high-frequency signal line is compensated, and the high-frequency performance of a product is improved.

As shown in fig. 16, the central axes of the horizontal lines of the first line segment 10531, the second line segment 10532, and the third line segment 10533 are on the same horizontal line, that is, the narrow area of the second line segment 10532 is symmetrical with respect to the central axis in the horizontal direction, or may be provided with asymmetry, which is not particularly limited; the two ends of the second line 10532, which are opposite to the central axis in the horizontal direction, are respectively narrowed by 1mil, and the line widths of the two ends of the second line 10532, which are opposite to the central axis in the horizontal direction, are respectively smaller than the line widths of the rest positions by 1 mil; in the embodiment of the application, the line width of the area covered by the cavity shell of the high-frequency signal line is subjected to narrow processing, and then the capacitance per unit length of the area is reduced, so that the impedance of the area is increased, and the influence of the shell on the impedance continuity of the high-frequency signal line is compensated; thereby improving signal integrity and optimizing high frequency performance. The line width of the region covered by the side wall of the cavity of the high-frequency signal line is reduced, so that the unit length capacitance of the region is reduced, the impedance of the region is increased, the impedance continuity of the high-frequency signal line is increased, and the high-frequency performance of the high-frequency signal line is optimized; therefore, the local line width of the high-frequency signal line is narrowed, so that the impedance continuity of the high-frequency signal line is improved, and the high-frequency performance of the high-frequency signal line is optimized.

The optical module provided by the embodiment of the application comprises a shell, wherein a laser chip is arranged in the shell, a first opening is formed in the side wall of the shell, a circuit board extends into the shell through the first opening, a laser driving chip is arranged outside the shell, and a gap is formed between the bottom end of a top plate of the first opening and the circuit board; high frequency signal line passes first opening and laser chip electricity from laser driver chip and is connected, lead to high frequency signal line part can be covered by the casing lateral wall, high frequency signal line is slightly little by the impedance of casing lateral wall coverage area in the original design, this application is through reducing the linewidth of high frequency signal line by the cavity lateral wall coverage area, thereby reduce this regional unit length electric capacity, increase this regional impedance, and then increase the impedance continuity of high frequency signal line self, thereby optimize the high frequency performance of high frequency signal line.

The above description is only for the specific embodiments of the present disclosure, but the scope of the present disclosure is not limited thereto, and any person skilled in the art will appreciate that changes or substitutions within the technical scope of the present disclosure should be covered by the scope of the present disclosure. Therefore, the protection scope of the present disclosure should be subject to the protection scope of the claims.

Claims (7)

1. A light module, comprising:

the surface of the circuit board is respectively provided with a laser driving chip and a high-frequency signal wire, and one end of the high-frequency signal wire is electrically connected with the laser driving chip;

the light emitting component is electrically connected with the circuit board and used for converting an electric signal into an optical signal;

the circuit board extends into the shell through the first opening, a laser chip is arranged in the shell, and the other end of the high-frequency signal line penetrates through the first opening and is electrically connected with the laser chip;

the laser chip is arranged in the shell, the laser driving chip is arranged outside the shell, a first gap is formed between the bottom end of the top plate of the first opening and the upper surface of the circuit board, the upper surface of the first gap is the bottom end of the top plate of the first opening, and the lower surface of the first gap is the high-frequency signal line;

the line width of the area covered by the first side wall in the high-frequency signal line is smaller than the line width of the rest area in the high-frequency signal.

2. The optical module according to claim 1, wherein the side wall of the housing includes a connecting portion that is closest to the laser driving chip in the housing;

the high-frequency signal line comprises a first line segment, a second line segment and a third line segment which are sequentially arranged, and the connecting part is positioned above the second line segment;

the width of the connecting part is the same as the length of the second line segment.

3. The light module of claim 1, wherein the circuit board is located partially inside the housing and partially outside the housing;

the surface of the circuit board is provided with a notch, the notch is used for embedding the shell, and the size of the notch is larger than that of the shell;

the second side wall and the third side wall of the shell are respectively provided with a second opening and a third opening; one side of the bottom end of the shell is hollowed upwards and inwards to form the second opening, and the other side of the bottom end of the shell is hollowed upwards and inwards to form the third opening;

the circuit board extends into the shell through the first opening, the second opening and the third opening.

4. The optical module of claim 2, wherein the width of each side of the horizontal central axis of the second line segment is less than 1mil than the width of each side of the horizontal central axis of the first line segment.

5. The optical module of claim 3, wherein a region between the second opening and the third opening is embedded in the notch.

6. The optical module of claim 1, wherein a first gap is provided between a bottom end of the top plate of the first opening and the upper surface of the circuit board, and a second gap is provided between a top end of the bottom plate of the first opening and the lower surface of the circuit board.

7. The optical module according to claim 1, wherein a bottom surface of the first opening, which is close to a side end of the laser driver chip, is hollowed upward to form the first gap.

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