CN212873154U

CN212873154U - Display device and circuit board

Info

Publication number: CN212873154U
Application number: CN202022204891.6U
Authority: CN
Inventors: 王睿; 陈泽君; 王建军; 刘晓石; 袁先锋
Original assignee: BOE Technology Group Co Ltd; Hefei Xinsheng Optoelectronics Technology Co Ltd
Current assignee: BOE Technology Group Co Ltd; Hefei Xinsheng Optoelectronics Technology Co Ltd
Priority date: 2020-09-30
Filing date: 2020-09-30
Publication date: 2021-04-02
Anticipated expiration: 2030-09-30

Abstract

The disclosure provides a display device and a circuit board, and belongs to the technical field of display. The display device comprises a light-emitting module, a circuit board and a conductive structure. Wherein, the surface of the light-emitting module is provided with a conductive part. The circuit board is arranged on the back surface of the light-emitting module and is provided with a first surface close to the light-emitting module; the first surface of the circuit board is provided with an exposed external conducting layer, and the external conducting layer is electrically connected with a ground wire of the circuit board. The conductive structure is positioned between the circuit board and the light-emitting module, and the external conductive layer is electrically connected with the conductive part. The display device can reduce electromagnetic interference in the circuit board.

Description

Display device and circuit board

Technical Field

The present disclosure relates to the field of display technologies, and in particular, to a display device and a circuit board.

Background

In the display device, a circuit board is required to provide power and data signals to the light emitting module so as to drive the light emitting module to display. However, the electromagnetic interference on the data lines often exceeds the standard, which reduces the display effect of the display device and causes it to fail to meet the electromagnetic interference control standard.

The above information disclosed in the background section is only for enhancement of understanding of the background of the present disclosure and therefore it may contain information that does not constitute prior art that is known to a person of ordinary skill in the art.

Disclosure of Invention

An object of the present disclosure is to provide a display device and a circuit board, which reduce electromagnetic interference on the circuit board.

In order to achieve the purpose, the technical scheme adopted by the disclosure is as follows:

according to a first aspect of the present disclosure, there is provided a display device including:

the surface of the light-emitting module is provided with a conductive part;

the circuit board is arranged on the back surface of the light-emitting module and is provided with a first surface close to the light-emitting module; the first surface of the circuit board is provided with an exposed external conducting layer, and the external conducting layer is electrically connected with a ground wire of the circuit board;

and the conductive structure is positioned between the circuit board and the light-emitting module and electrically connects the external conductive layer with the conductive part.

In an exemplary embodiment of the present disclosure, the circuit board includes a signal transmission region in which a signal transmission lead is disposed;

the external connection conducting layer comprises a first external connection conducting layer, and the orthographic projection of the first external connection conducting layer on the first surface is located in the signal transmission area.

In an exemplary embodiment of the present disclosure, the circuit board includes a power management area, in which a power management circuit is disposed;

the external conducting layer comprises a second external conducting layer, and the orthographic projection of the second external conducting layer on the first surface is located in the power management area.

In an exemplary embodiment of the present disclosure, the circuit board includes a plurality of metal wiring layers stacked, wherein the external conductive layer is located on a first metal wiring layer closest to the first surface.

In an exemplary embodiment of the present disclosure, the circuit board has a second surface far away from the light emitting module; the capacitor device and the resistor device of the circuit board are arranged on the second surface of the circuit board.

In an exemplary embodiment of the present disclosure, the back surface of the light emitting module is made of a conductive material;

the conductive structure is conductive foam or a conductive adhesive layer.

In an exemplary embodiment of the present disclosure, the display device further includes a heat conductive structure;

at least partial region of the external conducting layer is electrically connected with the back surface of the light-emitting module through the conducting structure; and the rest areas of the external conducting layer are electrically connected with the back surface of the light-emitting module through the heat conducting structure.

In an exemplary embodiment of the present disclosure, one of the electrically conductive structure and the thermally conductive structure, which forms a mesh in an orthographic projection on the circumscribed electrically conductive layer; the other of the electrically conductive structure and the thermally conductive structure, which is located in a mesh of the mesh in an orthographic projection on the circumscribing electrically conductive layer.

In an exemplary embodiment of the present disclosure, one of the electrically conductive structure and the thermally conductive structure, which is in a shape of a ring along an edge of the external conductive layer in an orthographic projection on the external conductive layer; the other of the electrically conductive structure and the thermally conductive structure, in orthographic projection on the circumscribing electrically conductive layer, is located inward of the annular inner edge.

In an exemplary embodiment of the present disclosure, the back surface of the light emitting module is an insulating material;

the conductive structure comprises a conductive adhesive tape, and the conductive adhesive tape is attached to the back surface of the light-emitting module and connected to the conductive part; the circuit board is arranged on one side, far away from the light-emitting module, of the conductive adhesive tape, and the external conductive layer is electrically connected with the conductive adhesive tape.

According to a second aspect of the present disclosure, there is provided a circuit board comprising a first surface and a second surface disposed opposite to each other; the resistance device and the capacitance device of the circuit board are arranged on the second surface;

the first surface of the circuit board is provided with an exposed external conducting layer, and the external conducting layer is electrically connected with a ground wire of the circuit board.

In the display device and the circuit board provided by the disclosure, the external conducting layer can weaken the interference electromagnetic wave in the circuit board, reduce the electromagnetic interference on the signal transmission lead wire and improve the anti-interference capability of the display device and the circuit board.

Drawings

The above and other features and advantages of the present disclosure will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings.

Fig. 1 is a schematic structural diagram of a display device according to an embodiment of the present disclosure.

Fig. 2 is a schematic structural diagram of a display device according to an embodiment of the present disclosure.

Fig. 3 is a schematic cross-sectional structure diagram of a circuit board in a signal transmission area according to an embodiment of the disclosure.

Fig. 4 is a schematic cross-sectional structure diagram of a circuit board in a power management area according to an embodiment of the disclosure.

Fig. 5 is a schematic structural diagram of a first surface of a circuit board according to an embodiment of the disclosure.

Fig. 6 is a schematic structural diagram of a second surface of a circuit board according to an embodiment of the disclosure.

Fig. 7 is a schematic top view distribution diagram of the electrically conductive structures and the thermally conductive structures on the external conductive layer according to an embodiment of the disclosure.

Fig. 8 is a schematic top view distribution diagram of the electrically conductive structures and the thermally conductive structures on the external conductive layer according to an embodiment of the disclosure.

Fig. 9 is a schematic top view distribution diagram of the conductive structures and the thermal conductive structures on the external conductive layer according to an embodiment of the disclosure.

Fig. 10 is a schematic top view distribution diagram of the electrically conductive structures and the thermally conductive structures on the external conductive layer according to an embodiment of the disclosure.

Fig. 11 is an electromagnetic interference test result of a circuit board according to an embodiment of the present disclosure.

The reference numerals of the main elements in the figures are explained as follows:

100. a light emitting module; 101. a conductive portion; 102. the back of the light-emitting module; 103. a frame of the light emitting module; 200. a circuit board; 201. a first surface; 202. a second surface; 210. connecting the conducting layer externally; 211. a first external conductive layer; 212. a second external conductive layer; 220. a ground wire; 230. a signal transmission lead; 240. bonding pads; 250. a metal post; 261. a resistance device; 262. a capacitor device; 270. a metal wiring layer; 271. a first metal wiring layer; 272. a second metal wiring layer; 273. a third metal wiring layer; 274. a fourth metal wiring layer; 275. a fifth metal wiring layer; 276. a sixth metal wiring layer; 281. an insulating layer; 282. an organic protective layer; 300. a conductive structure; 400. a heat conducting structure; A. a signal transmission region; B. a power management area.

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings. Example embodiments may, however, be embodied in many different forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of embodiments of the disclosure.

In the drawings, the thickness of regions and layers may be exaggerated for clarity. The same reference numerals denote the same or similar structures in the drawings, and thus detailed descriptions thereof will be omitted.

The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of embodiments of the disclosure. One skilled in the relevant art will recognize, however, that the embodiments of the disclosure can be practiced without one or more of the specific details, or with other methods, components, materials, and so forth. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring the primary technical ideas of the disclosure.

When a structure is "on" another structure, it may mean that the structure is integrally formed with the other structure, or that the structure is "directly" disposed on the other structure, or that the structure is "indirectly" disposed on the other structure via another structure. The terms "first" and "second", etc. are used merely as labels, and are not limiting on the number of their objects.

In the related art, a display device includes a light emitting module and a circuit board, and the circuit board is used for driving the light emitting module to display. The circuit board generally needs to include signal transmission leads and power management circuitry; the signal transmission lead is used for transmitting display related signals, such as data signals and the like, to the light emitting module. The power management circuit is used for providing required voltages for the light-emitting module. However, the power management circuit radiates electromagnetic waves during operation, which may generate noise or electromagnetic interference to signal transmission leads, electronic components, and the like within the circuit board.

The present disclosure provides a display device, referring to fig. 1 and 2, including a light emitting module 100, a circuit board 200, and a conductive structure 300. The surface of the light emitting module 100 has a conductive portion 101. The circuit board 200 is disposed on the back surface 102 of the light emitting module and has a first surface 201 close to the light emitting module 100. The first surface 201 of the circuit board 200 has an exposed external conductive layer 210, and the external conductive layer 210 is electrically connected to a ground line of the circuit board 200. The conductive structure 300 is located between the circuit board 200 and the light emitting module 100, and electrically connects the external conductive layer 210 with the conductive portion 101. In fig. 1 and 2, there is no joint between the first surface 201 and the back surface 102 of the light emitting module, and a certain gap exists, so as to clearly embody and distinguish the first surface 201 of the circuit board and the back surface 102 of the light emitting module; in practical applications, the gap may not be present. In other words, the first surface 201 and the back surface 102 of the light emitting module can be attached to each other without a gap.

In the display device provided by the present disclosure, the interference electromagnetic waves generated on the circuit board 200 may be partially transmitted to the external conductive layer 210, so that the external conductive layer 210 generates coupling charges and coupling electric fields, which may be rapidly dispersed into the conductive portion 101 of the light emitting module 100 through the conductive structure 300, thereby accelerating dissipation of the coupling charges and the coupling electric fields, and reducing the interference electromagnetic waves on the circuit board 200. In the display device, the external conductive layer 210 is located near the first surface 201 of the light emitting module 100, and the conductive structure 300 is located between the circuit board 200 and the light emitting module 100, which increases the grounding area of the circuit board 200 on one hand, and has a smaller distance between the external conductive layer 210 and the conductive portion 101 of the light emitting module 100 on the other hand, so that the coupling charges and the coupling electric field can be dissipated more rapidly, and the effect of reducing the interference electromagnetic waves is further improved. More importantly, the coupling charges and the coupling electric field generated on the external conductive layer 210 can be directly dispersed to the conductive portion through the conductive structure 300 located outside the circuit board 200, so that the transmission of the coupling charges and the coupling charges inside the circuit board 200 through the ground wire of the circuit board 200 is reduced, and the interference of the interfering electromagnetic waves to the signal transmission lead inside the circuit board 200 can be more effectively eliminated. Moreover, when static electricity is generated on the circuit board 200, the generated static electricity can also be dispersed to the conductive portion 101 of the light emitting module 100 through the external conductive layer 210 and the conductive structure 300, so as to disperse static charges and avoid electrostatic breakdown.

Thus, in the display device provided by the present disclosure, the electromagnetic interference on the circuit board 200 is weaker, which not only can ensure the normal display of the light emitting module 100, but also can ensure that the circuit board 200 meets the electromagnetic interference management and control standard.

The structure, principle and effect of the display device provided by the present disclosure will be further explained and explained with reference to the accompanying drawings.

The present disclosure provides a display device, which may be a liquid crystal display device, an OLED (organic electroluminescent diode) display device, a PLED (macromolecular organic electroluminescent diode) display device, an LED (light emitting diode) display device, a Micro LED (Micro light emitting diode) display device, a Mini LED (Mini light emitting diode) display device, or other types of display devices. The display device can be used as a mobile phone screen, a computer screen, an outdoor billboard, an electronic instrument panel, a vehicle-mounted display screen or other display devices.

In an embodiment of the present disclosure, the display device is a liquid crystal display device, and the light emitting module 100 may include a stacked backlight module and a liquid crystal panel, where a surface of the backlight module away from the liquid crystal panel is a back surface 102 of the light emitting module. Further, the display device is a vehicle-mounted display screen.

Fig. 3 is a schematic view of a circuit board cut at a position QQ' of fig. 6. Fig. 4 is a schematic structural view of a circuit board cut at a position PP' of fig. 6. Referring to fig. 3 and 4, the circuit board 200 provided by the present disclosure may include a plurality of stacked metal wiring layers 270, and the external conductive layer 210 is located on the first metal wiring layer 270 of the first surface 201. An insulating layer 281 is disposed between two adjacent metal wiring layers 270, and different metal wiring layers 270 may be electrically connected through a metal pillar 250 filled in a via. On the first surface 201 and the second surface 202 of the circuit board 200 opposite to the first surface 201, an organic protective layer 282 may be further disposed on the circuit board 200, for example, a green oil protective layer is disposed, and the green oil protective layer can not only protect the metal wiring layer 270, but also achieve a solder resist effect. Alternatively, the organic protection layer 282 may be formed by screen printing or the like, and the external connection conductive layer 210 of the first surface 201 is exposed when the organic protection layer 282 is formed. Further, the material of each metal wiring layer 270 and metal pillar 250 is copper metal.

Referring to fig. 1, the circuit board 200 provided by the present disclosure further includes an electronic component 260, and the electronic component 260 may be disposed on the second surface 202 of the circuit board 200. Referring to fig. 6, the electronic component may be a chip, a capacitor device 262, a resistor device 261, a transistor, or other electronic components. Further, a bonding pad 240 may be disposed on the metal wiring layer 270 closest to the second surface 202, and the electronic component may be bonded to the bonding pad 240, for example, may be bonded to the bonding pad 240 by soldering, conductive adhesive, or the like. In this manner, the electronic component can be electrically connected to the metal wiring layer 270 closest to the second surface 202.

Referring to fig. 3 and 6, the circuit board 200 provided by the present disclosure is provided with a signal transmission lead 230, and the signal transmission lead 230 may be disposed on one metal wiring layer 270 or may be disposed on multiple different metal wiring layers 270. Preferably, the signal transmission lead 230 may be disposed on the inner metal wiring layer 270, that is, the metal wiring layer 270 disposed between the metal wiring layer 270 closest to the first surface 201 and the metal wiring layer 270 closest to the second surface 202, so that the interference resistance of the signal transmission lead 230 may be improved. Further, the circuit board 200 may be provided with a bonding pad 240 on the metal wiring layer 270 closest to the second surface 202, and the signal transmission lead 230 may be electrically connected to the bonding pad 240 through a metal pillar passing through the insulating layer 281.

Referring to fig. 3 and 4, the circuit board 200 of the present disclosure is further provided with a ground line 220, and the ground line 220 may be provided to at least one metal wiring layer 270. Preferably, the ground lines 220 may be disposed on the respective metal wiring layers 270, and the ground lines 220 of the respective metal wiring layers 270 are electrically connected through the metal posts 250. Thus, the ground lines 220 on the whole circuit board 200 are electrically connected as a whole, which is convenient for maintaining the stability of signals on the whole circuit board 200 and for dissipating the interference electromagnetic waves.

In one embodiment of the present disclosure, a portion of the ground line 220 in the metal wiring layer 270 closest to the second surface 202 is exposed, and the exposed ground line 220 may be covered by a conductive tape or the like and electrically connected to the back surface 102 of the light emitting module. In this way, the interfering electromagnetic waves can be dissipated through the metal wiring layer 270 closest to the second surface 202, and the anti-electromagnetic interference effect of the circuit board 200 is further improved.

In one embodiment of the present disclosure, the display device may further include a shielding tape covering a portion of the second surface 202 of the circuit board 200 and a portion of the back surface of the light emitting module 100, so as to fix the circuit board 200 to the back surface 102 of the light emitting module and provide a certain electromagnetic shielding effect for the circuit board 200.

In one embodiment of the present disclosure, referring to fig. 3 and 4, the circuit board 200 may have six metal wiring layers 270, that is, a first metal wiring layer 271, a second metal wiring layer 272, a third metal wiring layer 273, a fourth metal wiring layer 274, a fifth metal wiring layer 275, and a sixth metal wiring layer 276, which are sequentially disposed. Wherein, the metal wiring layer 270 closest to the first surface 201 is a first metal wiring layer 271; the metal wiring layer 270 closest to the second surface 202 is a sixth metal wiring layer 276. Alternatively, referring to fig. 3, the signal transmission lead 230 may be disposed at the fourth metal wiring layer 274. Alternatively, referring to fig. 4 and 6, a bonding pad 240 is disposed on the sixth metal wiring layer 276, and a portion of the bonding pad 240 is used for connecting an electronic component, which is advantageous for connecting the resistance device 261 or the capacitance device 262. The sixth metal wiring layer 276 is provided with metal traces 2761, and at least some of the electronic components are electrically connected to the metal traces 2761. The ground lines 220 are disposed on the metal wiring layers 270, and the ground lines 220 are electrically connected to each other through the metal posts 250.

In one embodiment of the present disclosure, the signal transmission lead 230 may include a Low Voltage Differential signal lead on which a Low-Voltage Differential Signaling (LVDS) is transmitted to improve the interference rejection capability of the signal transmission lead 230. Preferably, the regulated impedance of the low voltage differential signal lead pair is 100 ohms.

Alternatively, from a top view, referring to fig. 5 and 6, the circuit board 200 has a signal transmission area a in which the signal transmission lead 230 is disposed. The external conductive layer 210 includes a first external conductive layer 211, and an orthographic projection of the first external conductive layer 211 on the first surface is located in the signal transmission region a. Thus, when the interfering electromagnetic wave of the circuit board 200 is conducted into the signal transmission area a, the interfering electromagnetic wave can be quickly dissipated and attenuated through the first external conductive layer 211, so as to weaken the intensity of the interfering electromagnetic wave in the signal transmission area a and weaken the interference of the interfering electromagnetic wave on the signal transmission lead 230.

Alternatively, the shape of the first external conductive layer 211 may be a rectangle, a diamond, a circle, an ellipse, or other shapes. Illustratively, the shape of the first external conductive layer 211 may be a rectangle. In one embodiment of the present disclosure, the first external conductive layer 211 may be a rectangle having a long side length of 40 mm and a short side length of 9 mm. In another embodiment of the present disclosure, the first external conductive layer 211 may be a rectangle having a long side length of 17 mm and a short side length of 7 mm. In another embodiment of the present disclosure, the first external conductive layer 211 may be a rectangle having a long side length of 12 mm and a short side length of 7 mm. It is to be understood that the above-described exemplary dimensions of the first external conductive layer 211 are merely examples. In other embodiments, the size of the first external conductive layer 211 may be adjusted according to the size of the circuit board 200, particularly according to the size of the signal transmission region a.

According to the circuit board 200 provided by the present disclosure, the interference of the interfering electromagnetic wave to the signal transmission lead 230 can be weakened by providing the first external conductive layer 211, so that the circuit board 200 can meet the electromagnetic interference control standard in more application environments. Thus, the circuit board 200 can be applied to different display devices, so that the universality of the circuit board 200 is improved, repeated development caused by development of a new circuit board 200 according to each different display device is avoided, and further, the problems of prolonged research and development period, waste of research and development resources and the like caused by repeated development of the circuit board 200 are avoided.

Alternatively, from a top view perspective, referring to fig. 5 and 6, the circuit board 200 may include a power management region B in which a power management circuit is disposed. The power management circuit can be used to generate voltages of various potentials required by the light emitting module 100 so as to provide different circuits of the light emitting module 100 with respective required power voltages. For example, the power management circuit may generate a ground voltage, a scan voltage, a driving power voltage, and the like, and generate a large amount of interference electromagnetic waves in the process of generating these voltages. Further, the power management circuit may include a power management chip and a voltage divider circuit, and the voltage divider circuit generates power voltages of different potentials by voltage division under the control of the power management chip. The electronic components of the power management circuit, such as the power management chip, the resistive device, the capacitive device, etc., may be electrically connected to the metal wiring layer 270 of the circuit board 200 closest to the second surface 202, and electrically connected through metal traces to form the power management circuit. The required metal routing lines may be entirely disposed on the metal wiring layer 270 closest to the second surface 202, or may be partially disposed on other metal wiring layers 270; the metal traces on the different metal routing layers 270 may be electrically connected through metal posts.

Optionally, the external conductive layer 210 includes a second external conductive layer 212, and an orthographic projection of the second external conductive layer 212 on the first surface is located in the power management region B. Thus, the interfering electromagnetic waves generated by the power management region B can be dissipated quickly through the second external conductive layer 212, so as to weaken the intensity of the interfering electromagnetic waves in the power management region B and reduce the interference of the interfering electromagnetic waves on the signal transmission lead 230. Accordingly, the second external conductive layer 212 can accelerate attenuation of interference electromagnetic waves in the power management region B, thereby reducing interference to the signal transmission lead 230, improving versatility of the circuit board of the present disclosure, and reducing repeated development of the circuit board.

It is understood that other circuit units may be selectively disposed on the circuit board 200 according to different configurations of the display device. Illustratively, in one embodiment of the present disclosure, the circuit board 200 may have a timing control region thereon, and a timing controller is disposed in the timing control region. Furthermore, the external connection conducting layer can further comprise a third external connection conducting layer, and the orthographic projection of the third external connection conducting layer on the first surface is located in the time sequence control area. Further exemplarily, in another embodiment of the present disclosure, the circuit board 200 may have a picture detection area thereon, and a picture detection circuit is disposed in the picture detection area. Further, the external conductive layer 210 may further include a fourth external conductive layer, and an orthogonal projection of the fourth external conductive layer on the first surface is located in the picture detection area. Still illustratively, in another embodiment of the present disclosure, the circuit board 200 may have a backlight management region thereon, and a backlight driving circuit is disposed in the backlight management region. Further, the external conductive layer 210 may further include a fifth external conductive layer, and an orthogonal projection of the fifth external conductive layer on the first surface is located in the backlight management area.

Optionally, the external conductive layer 210 is a non-hollow structure. Therefore, the electrical connection area between the external conductive layer 210 and the conductive structure 300 can be maximized, and the external conductive layer 210 has a larger area to couple the interference electromagnetic waves more efficiently, so that the transfer speed of the coupling charges and the coupling electric field is faster, and the anti-electromagnetic interference effect of the circuit board 200 is further improved.

The conductive structure 300 is disposed between the light emitting module 100 and the circuit board 200, and is used for dispersing the coupling charges and the coupling electric fields of the external conductive layer 210 on the circuit board 200 to the conductive portion 101 of the light emitting module 100, thereby reducing the interference electromagnetic waves in the circuit board 200. Preferably, the resistivity of the conductive structure 300 is less than 0.1 Ω · cm in a direction perpendicular to the back surface 102 of the light emitting module. Thus, the conductive structure 300 can be ensured to have a good conductive effect, and the dispersion speed of the coupling charges and the coupling electric field can be improved.

In some embodiments of the present disclosure, referring to fig. 1, the back side 102 of the light emitting module is made of a conductive material; in other words, the back surface 102 of the light emitting module is the conductive portion 101 of the light emitting module 100. Illustratively, the back surface 102 of the light emitting module is a back plate of a backlight source, and the back plate of the backlight source is a metal back plate.

Optionally, the conductive structure 300 may be a conductive structure 300 with a deformation capability so as to be able to be sufficiently contacted with both the external conductive layer 210 and the back surface 102 of the light emitting module, thereby reducing contact resistance between the conductive structure and the external conductive layer 210 and the back surface 102 of the light emitting module. Illustratively, the conductive structure 300 may be a conductive foam or a conductive adhesive layer. The thickness of the conductive foam or the conductive adhesive layer may be determined according to the gap between the external conductive layer 210 and the back surface 102 of the light emitting module, so as to be electrically connected to the external conductive layer 210 and the back surface 102 of the light emitting module, and not affect the attachment of the circuit board 200 to the back surface of the backlight module.

Optionally, referring to fig. 7 to 10, the display device further includes a heat conducting structure 400; at least a partial region of the external conductive layer 210 is electrically connected to the back surface 102 of the light emitting module through the conductive structure 300; the remaining region of the external conductive layer 210 is electrically connected to the back surface 102 of the light emitting module through the heat conductive structure 400. In fig. 7 to 10, the boundary of the external conductive layer 210 indicated by a dotted frame is larger than the ranges of the heat conductive structure 400 and the conductive structure 300 in order to clearly distinguish the boundary of the external conductive layer 210 from the boundaries of the heat conductive structure 400 and the conductive structure 300. In practical applications, the total range of the thermal conductive structure 400 and the electrical conductive structure 300 may be overlapped with the range of the external conductive layer 210.

Thus, heat generated by the electronic components on the circuit board 200 during operation, for example, heat generated by the power management chip during operation, can be conducted to the external conductive layer 210 along the metal wiring layer 270 and the metal posts 250, which are easy to conduct heat, and then conducted to the light emitting module 100 through the heat conducting structure 400, so as to improve the heat dissipation capability of the circuit board 200, especially the heat dissipation capability of the power management chip.

Optionally, the thermally conductive structure 400 includes a thermally conductive silicone layer. The material of the heat-conducting silicone grease layer can be heat-conducting silicone grease, which can effectively connect the external conducting layer 210 and the back surface 102 of the light-emitting module, so that the reduction of the heat-conducting effect caused by poor contact is avoided.

Alternatively, in one embodiment, referring to fig. 7 and 8, one of the electrically conductive structure 300 and the thermally conductive structure 400, which forms a grid in orthographic projection on the outer conductive layer 210; the other of the electrically conductive structure 300 and the thermally conductive structure 400, which is located in the mesh of the grid in an orthogonal projection on the outer conductive layer 210.

Exemplarily, referring to fig. 7, the orthographic projection of the electrically conductive structure 300 on the outer electrically conductive layer 210 forms a grid in which the thermally conductive structure 400 may be filled.

As another example, referring to fig. 8, the orthographic projection of the heat conductive structure 400 on the external conductive layer 210 forms a grid, and the electric conductive structure 300 may be filled in the grid.

Alternatively, in another embodiment, referring to fig. 9 and 10, one of the electrically conductive structure 300 and the thermally conductive structure 400, which is in orthographic projection on the circumscribing electrically conductive layer 210, is in the shape of a ring along the edge of the circumscribing electrically conductive layer 210; the other of the electrically conductive structure 300 and the thermally conductive structure 400, which is located within the inner edge of the ring in orthographic projection on the circumscribing electrically conductive layer 210.

Illustratively, referring to fig. 9, the heat conductive structure 400 is orthographically projected on the external conductive layer 210 as a ring shape along an edge of the external conductive layer 210, the ring shape having a hollow cavity; the conductive structure 300 is located within the inner edge of the ring in orthographic projection on the outer conductive layer 210, i.e. the conductive structure 300 is in the cavity. Further, the electrically conductive structure 300 fills the cavity, i.e. the outer edge of the orthographic projection of the electrically conductive structure 300 on the first surface coincides with the inner edge of the orthographic projection of the thermally conductive structure 400 on the outer electrically conductive layer 210.

As still another example, referring to fig. 10, the conductive structure 300 is orthographically projected on the external conductive layer 210 as a ring shape along an edge of the external conductive layer 210, the ring shape having a hollow cavity; the heat conducting structure 400 is located within the inner edge of the ring shape in orthographic projection on the outer electrically conductive layer 210, i.e. the heat conducting structure 400 is in the cavity. Further, the heat conducting structure 400 fills the cavity, i.e. the outer edge of the orthographic projection of the heat conducting structure 400 on the first surface coincides with the inner edge of the orthographic projection of the electrically conductive structure 300 on the outer electrically conductive layer 210.

Preferably, the area ratio of the conductive structure 300 to the conductive structure 400 is 0.8-1.2, so that the heat dissipation performance and the anti-electromagnetic interference performance of the circuit board 200 can be improved.

In some other embodiments of the present disclosure, referring to fig. 2, the back surface 102 of the light emitting module is an insulating material. The conductive structure 300 includes a conductive tape attached to the back surface 102 of the light emitting module and connected to the conductive portion 101; the circuit board 200 is disposed on a side of the conductive adhesive tape away from the light emitting module 100, and the external conductive layer 210 is electrically connected to the conductive adhesive tape.

For example, referring to fig. 2, the back surface 102 of the light emitting module is an insulating material, and the frame 103 of the light emitting module is a conductive metal material, so that the frame 103 of the light emitting module is the conductive portion 101 of the light emitting module 100. The conductive adhesive tape as the conductive structure 300 may be attached to the back surface 102 of the light emitting module, one end of which may extend to be connected to the frame 103, and the other end of which may extend to between the circuit board 200 and the light emitting module 100 and be adhered to the external conductive layer 210.

The circuit board interference condition of the display device is tested, and the test result is shown in fig. 11. Referring to fig. 11, a line segment L1 is a specification line of the peak; l2 is the gauge line for the mean; l3 represents measured data of the peak; l4 represents measured average data. In order to distinguish L1/L3 from L2/L4, the reference coordinate of L2/L4 is shifted down. When the measured data of the peak value exceeds the specification line of the peak value, the circuit board is shown not to meet the electromagnetic interference control standard; and when the actually measured average data exceeds the specification line of the average value, the circuit board is indicated not to meet the electromagnetic interference control standard. Referring to fig. 11, in the display device of the present disclosure, neither the measured data of the peak value nor the measured average data exceeds the corresponding specification line, so that the circuit board meets the electromagnetic interference control standard.

The present disclosure also provides a circuit board 200, referring to fig. 3 to 6, the circuit board 200 includes a first surface 201 and a second surface 202 oppositely disposed; the resistance device 261 and the capacitance device 262 of the circuit board 200 are disposed on the second surface 202; the first surface 201 of the circuit board 200 has an exposed external conductive layer 210, and the external conductive layer 210 is electrically connected to a ground line 220 of the circuit board 200.

Thus, in application, the circuit board 200 of the present disclosure may have the first surface 201 facing the carrier and attached to the carrier, and the external conductive layer 210 is electrically connected to the conductive portion 101 of the carrier through the conductive structure 300. Thus, when the circuit board 200 is in operation, the interfering electromagnetic waves generated on the circuit board 200 can be partially transmitted to the external conductive layer 210, so that the external conductive layer 210 generates coupling charges and coupling electric fields, and the coupling charges and the coupling electric fields can be rapidly dispersed into the conductive portion 101 of the carrier through the conductive structure 300, thereby accelerating dissipation of the coupling charges and the coupling electric fields, and reducing the interfering electromagnetic waves on the circuit board 200. The external conductive layer 210 is located near the first surface 201 of the carrier, and the conductive structure 300 is located between the circuit board 200 and the carrier, so that the external conductive layer 210 has a smaller distance from the conductive portion 101 of the carrier, which enables coupling charges and coupling electric fields to dissipate more rapidly, thereby improving the effect of reducing interference electromagnetic waves. More importantly, the coupling charges and the coupling electric field generated on the external conductive layer 210 can be directly transmitted through the conductive structure 300 located outside the circuit board 200, so that the transmission of the coupling charges and the coupling electric field inside the circuit board 200 through the ground line 220 of the circuit board 200 is reduced, and the interference of the interfering electromagnetic waves on the signal transmission lead 230 inside the circuit board 200 can be more effectively eliminated. Moreover, when static electricity is generated on the circuit board 200, the generated static electricity can also be dispersed to the conductive portion 101 of the carrier through the external conductive layer 210 and the conductive structure 300, so as to disperse static charges and avoid electrostatic breakdown.

The carrier may be a light emitting module 100, so that the display device described in the display device embodiment of the present disclosure may be obtained. As an application example of the circuit board 200, the display device provided in the present disclosure has disclosed details, principles, and effects of the circuit board 200 of the present disclosure, or the structure, principles, and effects of the circuit board 200 of the present disclosure can be reasonably derived from the description in the display device embodiment of the present disclosure, and the present disclosure is not repeated herein.

In one embodiment of the present disclosure, the circuit board 200 includes a signal transmission region a in which a signal transmission lead 230 is disposed; the external conductive layer 210 includes a first external conductive layer 211, and an orthographic projection of the first external conductive layer 211 on the first surface is located in the signal transmission region a.

In one embodiment of the present disclosure, the circuit board 200 includes a power management area B, in which a power management circuit is disposed; the external conductive layer 210 includes a second external conductive layer 212, and an orthogonal projection of the second external conductive layer 212 on the first surface is located in the power management region B.

In one embodiment of the present disclosure, the circuit board 200 includes a plurality of stacked metal wiring layers 270, wherein the external conductive layer 210 is located on the first metal wiring layer 270 of the first surface 201.

In one embodiment of the present disclosure, the external conductive layer 210 is a non-hollow structure.

It is to be understood that the disclosure is not limited in its application to the details of construction and the arrangements of the components set forth in the specification. The present disclosure is capable of other embodiments and of being practiced and carried out in various ways. The foregoing variations and modifications are within the scope of the present disclosure. It should be understood that the disclosure disclosed and defined in this specification extends to all alternative combinations of two or more of the individual features mentioned or evident from the text and/or drawings. All of these different combinations constitute various alternative aspects of the present disclosure. The embodiments of this specification illustrate the best mode known for carrying out the disclosure and will enable those skilled in the art to utilize the disclosure.

Claims

1. A display device, comprising:

the surface of the light-emitting module is provided with a conductive part;

2. The display device according to claim 1, wherein the circuit board includes a signal transmission region in which signal transmission leads are provided;

3. The display device according to claim 1, wherein the circuit board includes a power management area in which a power management circuit is disposed;

4. The display device according to claim 1, wherein the circuit board includes a plurality of metal wiring layers stacked, and wherein the external conductive layer is located on a first metal wiring layer closest to the first surface.

5. The display device according to claim 1, wherein the circuit board has a second surface away from the light emitting module; the capacitor device and the resistor device of the circuit board are arranged on the second surface of the circuit board.

6. The display device according to claim 1, wherein the back surface of the light emitting module is made of a conductive material;

the conductive structure is conductive foam or a conductive adhesive layer.

7. The display device according to any one of claims 1 to 6, wherein the display device further comprises a heat conducting structure;

8. The display device according to claim 7, wherein one of the electrically conductive structure and the thermally conductive structure forms a grid in an orthogonal projection on the circumscribing electrically conductive layer; the other of the electrically conductive structure and the thermally conductive structure, which is located in a mesh of the mesh in an orthographic projection on the circumscribing electrically conductive layer;

or one of the electric conduction structure and the heat conduction structure is in a ring shape along the edge of the external connection electric conduction layer in orthographic projection on the external connection electric conduction layer; the other of the electrically conductive structure and the thermally conductive structure, in orthographic projection on the circumscribing electrically conductive layer, is located inward of the annular inner edge.

9. The display device according to any one of claims 1 to 5, wherein the back surface of the light emitting module is made of an insulating material;

10. A circuit board, comprising a first surface and a second surface which are oppositely arranged; the capacitor device and the resistor device of the circuit board are arranged on the second surface;

11. The circuit board of claim 10, wherein the circuit board comprises a signal transmission region, and signal transmission leads are disposed in the signal transmission region;

12. The circuit board of claim 10, wherein the circuit board comprises a power management area, and wherein a power management circuit is disposed in the power management area;

13. The circuit board of claim 10, wherein the circuit board comprises a plurality of metal wiring layers stacked together, and wherein the external conductive layer is located on a first metal wiring layer closest to the first surface.