LED lamp bead and display device

Abstract

The utility model relates to an LED lamp bead and a display device. The LED lamp bead comprises a bearing substrate, a light-emitting chip, a first packaging part and a second packaging part, the light-emitting chip is arranged on the bearing substrate and is electrically connected with the bearing substrate; the first packaging part is arranged on the bearing substrate, a sealing cavity is defined by the first packaging part and the bearing substrate, and the light-emitting chip is located in the sealing cavity; the second packaging part is filled in the sealing cavity; and the second packaging part is configured to be in a liquid state when the LED lamp beads are in a working state and in a solid state when the LED lamp beads are in a non-working state, so that the sealing cavity is always isolated from the outside. Therefore, the probability that the light-emitting chip is aged and damaged due to erosion of external water vapor can be reduced, the packaging reliability of the LED lamp bead is improved, and the service life of the LED lamp bead is prolonged. The LED lamp bead can be applied to the display device, so that the display quality of the display device can be improved, and the service life of the display device is prolonged.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to an LED lamp bead and a display device. Background Art

[0002] The working principle of light emitting diode (LED) is as follows: the terminal voltage of PN junction forms a certain potential barrier. When the forward bias voltage is applied, the potential barrier drops, and the majority carriers in the P region and N region diffuse to each other. Since the electron mobility is much greater than the hole mobility, a large number of electrons will diffuse to the P region, forming an injection of minority carriers in the P region. These electrons recombine with holes in the valence band, and the energy obtained during the recombination is released in the form of light energy. It is widely used because of its many advantages such as high efficiency, high brightness, high reliability, energy saving and fast response speed.

[0003] The pixel elements used in LED display screens are LED lamp beads. The service life of LED lamp beads affects the display quality of LED display screens. However, the packaging reliability of LED lamp beads in related technologies is low, which makes LED lamp beads prone to aging, damage and other problems, shortening the service life of LED lamp beads and affecting the display quality of the display screen. Utility Model Content

[0004] Based on this, the present application provides an LED lamp bead and a display device to improve the packaging reliability of the LED lamp bead, extend the service life of the LED lamp bead, and further improve the display quality of the display device.

[0005] An embodiment of the first aspect of the present application provides an LED lamp bead, comprising: a carrying substrate, a light-emitting chip, a first packaging part and a second packaging part; the light-emitting chip is arranged on the carrying substrate and electrically connected to the carrying substrate; the first packaging part is arranged on the carrying substrate and together with the carrying substrate, encloses a sealed cavity, and the light-emitting chip is located in the sealed cavity; the second packaging part is filled in the sealed cavity; the second packaging part is configured to be liquid when the LED lamp bead is in a working state, and to be solid when the LED lamp bead is in a non-working state, so that the sealed cavity is always isolated from the outside world.

[0006] In one embodiment, the supporting substrate includes a bracket, on which a first pin and a second pin are disposed; the light-emitting chip is disposed on the bracket and connected to the first pin and the second pin; the first packaging part is disposed on the bracket and together with the bracket encloses the sealed cavity.

[0007] In one embodiment, the first pin and the second pin are both arranged on a side of the bracket away from the first packaging portion.

[0008] In one embodiment, the bracket includes a first part, and a first groove is opened on one side of the first part; the light-emitting chip is arranged in the first groove; the first packaging part is arranged on the first part, and together with the first groove, encloses the sealed cavity; the first pin and the second pin are both arranged on the side of the first part away from the first packaging part.

[0009] In one embodiment, a second groove is provided on the first portion and at the bottom of the first groove, and at least a portion of the light emitting chip is embedded in the second groove.

[0010] In one of the embodiments, the width of the first groove gradually increases from the bottom to the top of the first groove.

[0011] In one embodiment, the bracket further includes a second part, which is constructed as an annular structure; the second part is arranged around the first groove and connected to one side of the first part; and the first packaging part is disposed in the second part.

[0012] In one embodiment, the inner diameter of the second part gradually increases from a side of the second part close to the first part to a side of the second part far from the first part.

[0013] In one embodiment, the carrier base includes a substrate, and the light-emitting chip is disposed on the substrate and electrically connected to the substrate.

[0014] An embodiment of the second aspect of the present application provides a display device, characterized by comprising an LED lamp bead according to any one of the first aspects.

[0015] The above-mentioned LED lamp bead includes a carrier substrate, a light-emitting chip, a first packaging part and a second packaging part; the light-emitting chip is arranged on the carrier substrate and electrically connected to the carrier substrate; the first packaging part is arranged on the carrier substrate and encloses a sealed cavity together with the carrier substrate, and the light-emitting chip is located in the sealed cavity; the second packaging part is filled in the sealed cavity; when the LED lamp bead is in a working state, the temperature in the sealed cavity is high, the second packaging part changes from a solid state to a liquid state, and the second packaging part in a liquid state can fill the first packaging part and the gap on the carrier substrate; when the LED lamp bead stops working (that is, in a non-working state), the temperature in the sealed cavity gradually decreases, and the second packaging part in the sealed cavity and filled in the gap between the first packaging part and the carrier substrate gradually solidifies. In this way, no matter whether the LED lamp bead is in a working state or a non-working state, the second packaging part can always isolate the sealed cavity enclosed by the first packaging part and the carrier substrate from the outside world, thereby reducing the probability of aging and damage of the light-emitting chip due to erosion by external water vapor, improving the packaging reliability of the LED lamp bead, and extending the service life of the LED lamp bead. The LED lamp bead can be applied to a display device, thereby improving the display quality of the display device. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of the structure of LED lamp beads in some embodiments of the present application.

[0017] Figure 2 Another structural schematic diagram of an LED lamp bead in some embodiments of the present application.

[0018] Description of reference numerals:

[0019] 10. LED lamp beads;

[0020] 110, supporting base; 111, substrate; 112, bracket; 1121, first part; 1121a, first groove; 1121b, second groove; 1122, second part; 113, first pin; 114, second pin; 120, light-emitting chip; 130, first packaging part; 140, sealing cavity; 150, protrusion. DETAILED DESCRIPTION

[0021] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0022] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.

[0023] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0024] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0025] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0026] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only implementation method.

[0027] The working principle of light emitting diode (LED) is as follows: the terminal voltage of PN junction forms a certain potential barrier. When the forward bias voltage is applied, the potential barrier drops, and the majority carriers in the P region and N region diffuse to each other. Since the electron mobility is much greater than the hole mobility, a large number of electrons will diffuse to the P region, forming an injection of minority carriers in the P region. These electrons recombine with holes in the valence band, and the energy obtained during the recombination is released in the form of light energy. It is widely used because of its many advantages such as high efficiency, high brightness, high reliability, energy saving and fast response speed.

[0028] The pixel elements used in LED display screens are LED lamp beads. The service life of LED lamp beads affects the display quality of LED display screens. However, the packaging reliability of LED lamp beads in related technologies is low, which makes LED lamp beads prone to aging, damage and other problems, shortening the service life of LED lamp beads and affecting the display quality of the display screen.

[0029] Based on the above technical problems, the present application provides an LED lamp bead and a display device to improve the packaging reliability of the LED, extend the service life of the LED lamp bead, and further improve the display quality of the display device.

[0030] Figure 1 The schematic diagram of the structure of the LED lamp beads in some embodiments of the present application is shown; Figure 2 A schematic diagram of the structure of LED lamp beads in some embodiments of the present application is shown.

[0031] First, see Figure 1 and Figure 2As shown, the embodiment of the present application provides an LED lamp bead 10, including: a supporting substrate 110, a light-emitting chip 120, a first packaging part 130 and a second packaging part (not shown); the light-emitting chip 120 is arranged on the supporting substrate 110 and is electrically connected to the supporting substrate 110; the first packaging part 130 is arranged on the supporting substrate 110, and together with the supporting substrate 110, it encloses a sealed cavity 140, and the light-emitting chip 120 is located in the sealed cavity 140; the second packaging part is filled in the sealed cavity 140; the second packaging part is configured to be liquid when the LED lamp bead 10 is in a working state, and to be solid when the LED lamp bead 10 is in a non-working state, so that the sealed cavity 140 is always isolated from the outside.

[0032] Specifically, the carrier substrate 110 can be made of plastic; from a microscopic perspective, there are a large number of small gaps on the carrier substrate 110. The first encapsulation part 130 can be formed of a transparent polymer. From a microscopic perspective, there are a large number of small gaps on the first encapsulation part 130. There is a certain difference in the thermal expansion coefficients of the first encapsulation part 130 and the carrier substrate 110. When the LED lamp bead 10 is in a working state, the temperature of the sealed cavity 140 is relatively high, and the first encapsulation part 130 and the carrier substrate 110 are both thermally expanded. Due to the difference in the thermal expansion coefficients of the two, the first encapsulation part 130 and the carrier substrate 110 are squeezed and deformed, resulting in the enlargement of the gaps on the first encapsulation part 130 and / or the carrier substrate 110, and the external water vapor enters the sealed cavity 140 through the gaps, causing the LED lamp bead 10 to be prone to aging, damage and other problems. The second encapsulation part is configured to be in liquid state when the LED lamp bead 10 is in working state, and the second encapsulation part in liquid state can fill the gaps on the first encapsulation part 130 and the carrier substrate 110; and when the LED lamp bead 10 is in non-working state, the temperature in the sealed cavity 140 gradually decreases, and the second encapsulation part in the sealed cavity 140 and in the gaps between the first encapsulation part 130 and the carrier substrate 110 gradually solidifies. In this way, no matter whether the LED lamp bead 10 is in working state or non-working state, the second encapsulation part can always isolate the sealed cavity 140 enclosed by the first encapsulation part 130 and the carrier substrate 110 from the outside world, thereby reducing the probability of aging and damage of the light-emitting chip 120 due to erosion by external water vapor, improving the packaging reliability of the LED lamp bead 10, and extending the service life of the LED lamp bead 10.

[0033] In summary, the LED lamp bead 10 provided in the embodiment of the present application is configured such that the first packaging part 130 is arranged on the supporting substrate 110, and together with the supporting substrate 110, a sealed cavity 140 is enclosed, and the light-emitting chip 120 is located in the sealed cavity 140; the second packaging part is filled in the sealed cavity 140, and the second packaging part is configured to be liquid when the LED lamp bead 10 is in a working state, and to be solid when the LED lamp bead 10 is in a non-working state. In this way, the second packaging part can always isolate the sealed cavity 140 enclosed by the first packaging part 130 and the supporting substrate 110 from the outside world, thereby reducing the probability of aging and damage of the light-emitting chip 120 due to erosion by external water vapor, improving the packaging reliability of the LED lamp bead 10, and extending the service life of the LED lamp bead 10.

[0034] In one embodiment, the melting point of the material of the second packaging portion is lower than the minimum temperature generated when the light emitting chip 120 emits light.

[0035] Therefore, when the LED lamp bead 10 is working and the light-emitting chip 120 is emitting light, the second packaging part will quickly convert from solid to liquid, and fill the gaps in the first packaging part 130 and the supporting substrate 110, thereby ensuring the isolation of the sealed cavity 140 from the outside world; when the LED lamp bead 10 stops working and the light-emitting chip 120 does not emit light, the second packaging part gradually converts from liquid to solid, thereby effectively isolating the sealed cavity 140 from the outside world, effectively improving the packaging reliability of the LED lamp bead 10, and thus extending the service life of the LED lamp bead 10.

[0036] In one embodiment, the material of the second packaging part includes wax. The melting point of wax is between 57°C and 63°C, and the minimum temperature of the light-emitting chip 120 when emitting light is 80°C. In this way, by filling the sealed cavity 140 with wax, the sealed cavity 140 can be effectively isolated from the outside world, effectively improving the packaging reliability of the LED lamp bead 10, thereby extending the service life of the LED lamp bead 10. In addition, wax is a transparent material and does not affect the light emission of the LED lamp bead.

[0037] like Figure 1 As shown, in one embodiment, the carrier substrate 110 includes a bracket 112, on which a first pin 113 and a second pin 114 are disposed; the light emitting chip 120 is disposed on the bracket 112 and connected to the first pin 113 and the second pin 114; the first packaging portion 130 is disposed on the bracket 112 and together with the groove 113, a sealed cavity 140 is enclosed. Specifically, the light emitting chip 120 can be disposed on the bracket 112 in a normal manner.

[0038] Therefore, by making the supporting base 110 include a bracket 112, a first pin 113 and a second pin 114 are set on the bracket 112, and the light-emitting chip 120 is connected to the first pin 113 and the second pin 114. In this way, the first pin 113 and the second pin 114 can facilitate the connection between the light-emitting chip 120 and other electrical components to ensure the normal operation and use of the LED lamp bead 10.

[0039] like Figure 1 As shown, in one embodiment, the first pin 113 and the second pin 114 are both disposed on a side of the bracket 112 away from the first packaging portion 130 .

[0040] Therefore, when the LED lamp bead 10 is installed on the circuit board, the first pin 113 and the second pin 114 on the bracket 112 can be directly attached to and welded to the pads on the circuit board, so that the first pin 113 and the second pin 114 of the LED can be firmly combined with the pads on the circuit board.

[0041] like Figure 1 As shown, in one embodiment, the bracket 112 includes a first part 1121, and a first groove 1121a is opened on one side of the first part 1121; the light-emitting chip 120 is arranged in the first groove 1121a; the first packaging part 130 is arranged on one side of the first part 1121, and together with the first groove 1121a, a sealed cavity 140 is enclosed; the first pin 113 and the second pin 114 are both arranged on the side of the first part 1121 away from the first packaging part 130.

[0042] Thus, by making the bracket 112 include the first part 1121, and the first part 1121 has a first groove 1121a on one side, the light emitting chip 120 is arranged in the first groove 1121a, and the first packaging part 130 is arranged on one side of the first part 1121, and the sealing cavity 140 is enclosed together with the first groove 1121a, so that the sealing between the first packaging part 130 and the bracket 112 can be improved, the light emitting chip 120 is protected, and the packaging reliability of the LED lamp bead 10 is improved. By making the first pin 113 and the second pin 114 both arranged on the side of the first part 1121 away from the first packaging part 130, the LED lamp bead can be conveniently and stably mounted on the circuit board.

[0043] like Figure 1 As shown, in one embodiment, a second groove 1121b is provided on the first portion 1121 and at the bottom of the first groove 1121a, and at least a portion of the light emitting chip 120 is embedded in the second groove 1121b.

[0044] Therefore, by setting a second groove 1121b on the first part 1121 and at the bottom of the first groove 1121a, at least a part of the light-emitting chip 120 is embedded in the second groove 1121b. In this way, the light-emitting chip can be more firmly set in the first groove, thereby improving the connection reliability between the light-emitting chip and the bracket, thereby improving the reliability of the LED lamp bead.

[0045] like Figure 1 As shown, in one embodiment, the width of the first groove 1121a gradually increases from the bottom to the top of the first groove 1121a.

[0046] Therefore, the light emitting chip 120 can be conveniently installed in the first groove 1121 a of the first portion 1121 .

[0047] like Figure 1 As shown, in one embodiment, the bracket 112 also includes a second part 1122, and the second part 1122 is constructed as an annular structure; the second part 1122 is arranged around the first groove 1121a and connected to one side of the first part 1121; the first packaging part 130 is disposed in the second part 1122.

[0048] Thus, the problem of glue overflow when the first packaging part is formed by glue pouring can be avoided, so that the first packaging part is easier to form and the sealing protection effect of the first packaging part is better.

[0049] like Figure 1 As shown, in one embodiment, the inner diameter of the second portion 1122 gradually increases from a side of the second portion 1122 close to the first portion 1121 to a side of the second portion 1122 away from the first portion 1121 .

[0050] In this way, the first packaging part 130 can be conveniently formed in the second part 1122 , thereby avoiding the problem of glue overflow and improving the sealing of the first packaging part, thereby improving the packaging reliability of the LED lamp bead 10 .

[0051] like Figure 2 As shown, in one embodiment, the carrier substrate 110 includes a substrate 111, and the light emitting chip 120 is disposed on the substrate 111 and electrically connected to the substrate 111. Specifically, the light emitting chip 120 is flip-chip disposed on the substrate 111.

[0052] Therefore, when the light emitting chip 120 is installed, the positive and negative electrodes of the light emitting chip 120 can be directly connected to the substrate 111 without wire bonding, thus eliminating the wire bonding process and improving installation efficiency.

[0053] like Figure 1 , Figure 2As shown, in one embodiment, a protrusion 150 is disposed on a side of the first packaging portion 130 away from the carrier substrate 110 , and the protrusion 150 corresponds to the position of the light emitting chip 120 ; the protrusion 150 has a preset curvature radius.

[0054] Therefore, the protrusion 150 can be a lens of the light-emitting chip 120, so that the emitted light is refracted and reflected to emit, which can achieve a focusing effect, improve the brightness of the LED lamp bead 10, and reduce power consumption and cost.

[0055] like Figure 1 , Figure 2 As shown, in one embodiment, the protrusion 150 is integrally formed with the first packaging part 130. Specifically, the protrusion 150 is formed on a surface of the first packaging part 130 away from the carrier substrate 110; for example, the protrusion 150 can be designed on a mold, and the protrusion 150 can be formed on the surface of the first packaging part 130 by mold injection.

[0056] Therefore, the first packaging part 130 can be reused as a lens, corresponding to the position of the light-emitting chip 120, so that a wide viewing angle can be ensured, a higher axial light intensity brightness can be obtained, and power consumption and cost can be reduced.

[0057] In one embodiment, the light emitting chip 120 includes at least one of a first LED chip, a second LED chip and a third LED chip, wherein the first LED chip, the second LED chip and the third LED chip correspond to red light, green light and blue light respectively.

[0058] In one embodiment, the material of the first packaging portion 130 includes at least one of polycarbonate (PC), polyphthalimide (PPA), silicone resin, silica gel and epoxy resin;

[0059] In a second aspect, an embodiment of the present application provides a display device, characterized by comprising an LED lamp bead 10 according to any one of the first aspects. In this way, the display quality of the display device can be improved and the service life of the display device can be extended.

[0060] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0061] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. An LED lamp bead, characterized in that: include: A carrier substrate; A light emitting chip is disposed on the carrier substrate and electrically connected to the carrier substrate; A first packaging part is disposed on the carrier substrate and together with the carrier substrate, encloses a sealed cavity, and the light-emitting chip is located in the sealed cavity; The second packaging part is filled in the sealed cavity; the second packaging part is configured to be in liquid state when the LED lamp bead is in a working state, and to be in solid state when the LED lamp bead is in a non-working state, so that the sealed cavity is always isolated from the outside.

2. The LED lamp bead according to claim 1, characterized in that: The supporting base includes a bracket, on which a first pin and a second pin are arranged; the light-emitting chip is arranged on the bracket and connected to the first pin and the second pin; the first packaging part is arranged on the bracket and together with the bracket surrounds the sealed cavity.

3. The LED lamp bead according to claim 2, characterized in that: The first pin and the second pin are both arranged on a side of the bracket away from the first packaging portion.

4. The LED lamp bead according to claim 2, characterized in that: The bracket includes a first part, and a first groove is opened on one side of the first part; the light-emitting chip is arranged in the first groove; the first packaging part is arranged on one side of the first part, and together with the first groove, encloses the sealed cavity; the first pin and the second pin are both arranged on the side of the first part away from the first packaging part.

5. The LED lamp bead according to claim 4, characterized in that: A second groove is arranged on the first part and at the bottom of the first groove, and at least a part of the light emitting chip is embedded in the second groove.

6. The LED lamp bead according to claim 4, characterized in that: The width of the first groove gradually increases from the bottom to the top of the first groove.

7. The LED lamp bead according to claim 4, characterized in that: The bracket also includes a second part, which is constructed as an annular structure; the second part is arranged around the first groove and connected to one side of the first part; the first packaging part is arranged in the second part.

8. The LED lamp bead according to claim 7, characterized in that: The inner diameter of the second part gradually increases from a side of the second part close to the first part to a side of the second part far from the first part.

9. The LED lamp bead according to any one of claims 1 to 8, characterized in that: The carrier substrate comprises a base plate, and the light emitting chip is arranged on the base plate and is electrically connected to the base plate.

10. A display device, characterized in that: It comprises the LED lamp bead according to any one of claims 1 to 9.

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