Preparation method of lamp bead, lamp bead and backlight module

Abstract

The application belongs to the technical field of display devices, and particularly relates to a preparation method of a lamp bead, the lamp bead and a backlight module. The preparation method of the lamp bead comprises the following steps: preparing materials; preparing an electrode layer on one side of a substrate; connecting a chip to the electrode layer, two electrodes of the chip being electrically connected to two adjacent conductive blocks respectively; preparing an encapsulation layer on the conductive blocks; the encapsulation layer comprises a plurality of spaced-apart light blocking layers, and the light blocking layers extend along a second direction; any chip has two mutually facing away sides provided with the light blocking layers, and the other two sides of any chip are exposed to the light blocking layers; and cutting the substrate, the conductive blocks and the encapsulation layer along a first direction and a second direction respectively to form the lamp bead. The preparation method of the lamp bead can expand the light emitting area of the lamp bead, thereby reducing the number of the lamp beads used to improve the light emitting uniformity.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of display devices, and particularly relates to a preparation method of a lamp bead, the lamp bead and a backlight module. BACKGROUND

[0002] Information is a big trend in today's era, and liquid crystal display is an important medium for information transmission. With the increasing application of liquid crystal display, people have higher requirements for the light output quality of liquid crystal display panels.

[0003] The backlight module is a device for supplying light to display images in the liquid crystal display panel, which includes a plurality of lamp beads; in the traditional backlight module, a lamp bead with single top light emission is often used.

[0004] However, the light emitting area of the lamp bead has great limitations, so a large number of lamp beads need to be used and densely arranged on the lamp strip or PCB to ensure that the liquid crystal display panel has sufficient display brightness, which will increase the ratio of OD (optical distance, which refers to the height of the lamp bead in this application) and Pitch (which refers to the distance between two adjacent lamp beads) on the backlight module, thereby affecting the uniformity of light emission. SUMMARY

[0005] The purpose of the embodiments of the present application is to provide a preparation method of a lamp bead, a lamp bead and a backlight module, aiming to solve the problem of how to expand the light emitting area of the lamp bead to reduce the number of lamp beads used to improve the uniformity of light emission.

[0006] To achieve the above-mentioned purpose, the technical solution adopted by the present application is:

[0007] First, a preparation method of a lamp bead is provided, comprising the following steps:

[0008] Preparation of materials, preparation of a substrate and a plurality of chips;

[0009] Preparation of an electrode layer, preparation of the electrode layer on one side of the substrate; wherein the electrode layer comprises a plurality of spaced conductive blocks, and each conductive block is insulated from the substrate;

[0010] Die bonding, connecting the chips to the electrode layer, two electrodes of the chip are respectively electrically connected to two adjacent conductive blocks; wherein each chip is arranged in a first direction and arranged in multiple columns in a second direction; the first direction and the second direction are staggered;

[0011] forming a packaging layer on the conductive blocks; the packaging layer comprises a plurality of light-blocking layers arranged at intervals, the light-blocking layers extend along the second direction; any two mutually facing away sides of the chip are provided with the light-blocking layers, and the remaining two sides of any chip are exposed from the light-blocking layers; and

[0012] cutting the substrate, the conductive blocks and the packaging layer along the first direction and the second direction respectively to form a lamp bead.

[0013] Optionally, in some embodiments, the packaging step comprises: dotting glue on the conductive blocks to form the light-blocking layers.

[0014] Optionally, in some embodiments, any light-blocking layer is formed with a reflective surface on the side facing the corresponding chip,

[0015] wherein, the two reflective surfaces on the same lamp bead are arranged in parallel; or, the two reflective surfaces on the same lamp bead are arranged at a predetermined angle.

[0016] Optionally, in some embodiments, the predetermined angle is 120 degrees.

[0017] Optionally, in some embodiments, the step of forming an electrode layer comprises:

[0018] laying a conductive film on the substrate, forming separation grooves on the conductive film through an etching process, the extension path of the separation grooves is along the first direction, and a plurality of separation grooves are arranged at intervals along the second direction, and the part of the conductive film between two adjacent separation grooves forms the conductive block.

[0019] Optionally, in some embodiments, the step of forming an electrode layer comprises: installing a support on the substrate; the support corresponds to the chip one by one, and any support comprises two conductive blocks; the support has a mounting cavity; the mounting cavity has two cavity walls made of transparent material, and any cavity wall is provided with a receiving groove for forming the light-blocking layer;

[0020] The die bonding step further comprises: installing each chip in the corresponding mounting cavity;

[0021] In the packaging step, the light-blocking layer is formed in the receiving groove by means of dispensing glue.

[0022] Optionally, in some embodiments, the chip is a positive chip, and the two electrodes of the chip are electrically connected to the corresponding conductive blocks by gold wires; or, the chip is a flip chip and is erected on two adjacent conductive blocks.

[0023] Optionally, in some embodiments, the packaging step further comprises:

[0024] Filling glue, filling fluorescent glue between two adjacent light blocking layers, and making the fluorescent glue cover the chip.

[0025] Secondly, a lamp bead is provided by the preparation method of the lamp bead; the lamp bead comprises the chip, the power connection part, and the light blocking part; the chip is electrically connected to the power connection part and is configured to emit light; the light blocking part is provided with two and is respectively located at two sides of the chip and is connected to the power connection part.

[0026] The electrode layer can form the power connection part through the cutting step, and the light blocking layer can form the light blocking part through the cutting step.

[0027] Thirdly, a backlight module is provided, comprising a plurality of the lamp beads; the backlight module further comprises a circuit board, and each of the lamp beads is electrically mounted on the circuit board.

[0028] The lamp bead prepared by the preparation method of the lamp bead has three light emitting surfaces, which can effectively expand the light emitting area of the lamp bead, thereby reducing the use amount of the lamp bead and improving the uniformity of light emission. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments or exemplary technical descriptions will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0030] Figure 1 The processing flow chart of the preparation method of the lamp bead provided by an embodiment of the present application is shown in the figure.

[0031] Figure 2 The principle schematic diagram of the substrate pressing process provided by an embodiment of the present application is shown in the figure.

[0032] Figure 3 The principle schematic diagram of part of the process of the face-down chip in the packaging process provided by an embodiment of the present application is shown in the figure.

[0033] Figure 4 Part of the process principle diagram of flip chip in packaging process is provided for an embodiment of the present application;

[0034] Figure 5 The principle diagram of cutting process is provided for an embodiment of the present application;

[0035] Figure 6 The structure diagram of lamp bead is provided for an embodiment of the present application;

[0036] Figure 7 The structure diagram of lamp bead is provided for another embodiment of the present application;

[0037] Figure 8 The structure diagram of lamp bead is provided for another embodiment of the present application;

[0038] Figure 9 The structure diagram of lamp bead is provided for another embodiment of the present application;

[0039] Figure 10 The structure diagram of lamp bead is provided for another embodiment of the present application;

[0040] Figure 11 The structure diagram of lamp bead is provided for another embodiment of the present application.

[0041] In the drawings, the reference signs are as follows: 100, lamp bead; 10, chip; 10A, normal chip; 10B, flip chip; 11, first electrode; 12, second electrode; 13, gold wire; 20, electrode layer; 20A, support; 21, conductive block; 22, electricity connection part; 23, separation groove; 30, substrate; 31, insulation layer; 32, support layer; 40, packaging layer; 41, light blocking layer; 411, light blocking part; 412, reflecting surface; 42, fluorescent glue; 421, light emitting part; C, first direction; D, second direction; E, predetermined included angle. DETAILED DESCRIPTION

[0042] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application.

[0043] It is to be noted that when a component is referred to as being "on" or "disposed on" another component, it can be directly on the other component or indirectly on the other component. When a component is referred to as being "connected to" another component, it can be directly or indirectly connected to the other component. The terms "upper", "lower", "left", "right", and the like indicate relative positions or orientation relationships based on the positions or orientation relationships shown in the drawings, and are only for the convenience of description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. For those skilled in the art, the specific meanings of the above terms can be understood according to specific circumstances. The terms "first", "second" are only for the convenience of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features.

[0044] Please refer to Figure 1 The embodiment of the present application provides a lamp bead preparation method, which comprises the following steps: a material preparation step, an electrode layer 20 preparation step, a die bonding step and a packaging step. Please refer to Figures 1 to 5 Optionally, the foregoing steps are performed in the following order:

[0045] S1: material preparation, preparing a substrate 30 and a plurality of chips 10;

[0046] S2: preparing an electrode layer 20, preparing the electrode layer 20 on one side of the substrate 30; wherein the electrode layer 20 comprises a plurality of spaced conductive blocks 21, and each conductive block 21 is insulated from the substrate 30;

[0047] S3: die bonding, connecting the chip 10 to the electrode layer 20; wherein two electrodes of the chip 10 are respectively electrically connected to two adjacent conductive blocks 21; wherein each chip 10 is arranged in a first direction C and arranged in a plurality of columns in a second direction D; the first direction C and the second direction D are staggered;

[0048] S4: packaging, preparing a packaging layer 40 on the conductive block 21; the packaging layer 40 comprises a plurality of spaced light blocking layers 41, and the light blocking layer 41 extends in the second direction D; any chip 10 has two mutually facing sides provided with the light blocking layer 41, and the remaining two sides of any chip 10 are exposed to the light blocking layer 41;

[0049] S5: cutting, cutting the substrate 30, the conductive block 21 and the packaging layer 40 along the first direction C and the second direction D respectively to form a lamp bead 100 as shown in any of Figures 6 to 11 The embodiment of the present application provides a lamp bead preparation method, which comprises the following steps: a material preparation step, an electrode layer 20 preparation step, a die bonding step and a packaging step. Please refer to

[0050] The two electrodes of the chip 10 are a first electrode and a second electrode respectively, and the first electrode and the second electrode are electrically connected to two different conductive blocks 21 respectively so that the lamp bead 100 can be powered on.

[0051] It can be understood that the preparation method of the lamp bead provided by the present application can electrically connect the chip 10 and the electrode layer 20 through the material preparation step, the electrode layer 20 preparation step and the die bonding step, so as to connect an external power supply device to realize light emission. Through the packaging step, the light blocking layer 41 is formed on the two sides of any chip 10, thereby blocking the light emission in the corresponding direction; and the remaining two sides of any chip 10 are exposed to the light blocking layer 41, so that the chip 10 can emit light on the two sides. Through the cutting step, the lamp bead 100 with three light emitting surfaces can be formed. Therefore, please refer to Figures 6 to 11 The lamp bead 100 prepared by the preparation method of the lamp bead provided by the present application has three light emitting surfaces, which can effectively expand the light emitting area of the lamp bead 100, thereby reducing the use amount of the lamp bead 100 and improving the uniformity of light emission. Since the light emitting area of the lamp bead 100 is expanded, the use amount of the lamp bead 100 can be reduced and the distance between two adjacent lamp beads 100 can be increased under the premise of ensuring the light emission intensity, thereby reducing the ratio of the optical distance (OD) to the pitch (Pitch) to improve the uniformity of light emission. In summary, the present application solves the problem of how to expand the light emitting area of the lamp bead 100, thereby reducing the use amount of the lamp bead 100 to improve the uniformity of light emission.

[0052] After the processing is completed, the electrode layer 20 is peeled off from the surface of the substrate 30, and the lamp bead 100 can be electrically connected to the circuit structure to realize the light emission function.

[0053] Optionally, the chips 10 are arranged in an array, and the first direction C is perpendicular to the second direction D.

[0054] Please refer to Figure 1 and Figure 3Optionally, in the embodiment, the encapsulating step includes: applying glue on the conductive block 21 to form the light blocking layer 41. The glue used to form the light blocking layer 41 is a light blocking material. It can be understood that the glue can form a stable cavity wall-shaped light blocking layer 41 after curing; the height of the light blocking layer 41 can be adjusted by controlling the amount of glue and the way of dispensing, so as to match the height of the chip 10 itself, thereby reducing the height of the lamp bead 100; in this way, reducing the height of the lamp bead 100 can reduce the OD / Pitch value, thereby improving the uniformity of light emission. In addition, using the foregoing lamp bead 100 to produce a display panel, since the height of the lamp bead 100 is reduced, the thickness of the display panel can be effectively reduced; since the amount of the lamp bead 100 is reduced, the production cost of the display panel can be effectively reduced.

[0055] Optionally, the glue used to form the light blocking layer 41 is a white high-reflective glue containing titanium dioxide, zinc oxide and silicon dioxide materials, which can block light and has high reflectivity. It can be understood that in the embodiment, the light blocking layer 41 can converge light towards the chip 10, thereby helping to improve the illumination intensity of the lamp bead 100 and further reducing the amount of the lamp bead 100 used.

[0056] Referring to Figures 6 to 11 Optionally, in some embodiments, any light blocking layer 41 is formed with a reflective surface 412 on the side facing the corresponding chip 10. It can be understood that any reflective surface 412 has a light converging effect, thereby enhancing the light emission intensity of the lamp bead 100.

[0057] Referring to Figure 6 , Figure 8 , Figure 9 and Figure 11 Optionally, in some embodiments, the two reflective surfaces 412 on the same lamp bead 100 are arranged in parallel. It can be understood that the chip 10 in the conductive state emits light to the surrounding and top; among them, on the two sides provided with the light blocking layer 41, after the light irradiates to the reflective surface 412, the light emitting surface can reflect the light towards the chip 10, and the illumination intensity of the lamp bead 100 in the light emission area can be enhanced.

[0058] Referring to Figure 7 and Figure 10 Optionally, in some embodiments, the two reflective surfaces 412 on the same lamp bead 100 are arranged at a predetermined included angle E. It can be understood that by controlling the size of the predetermined included angle E, the angle of the reflected light at the reflective surface 412 can be adjusted, so as to converge the light towards a specific area.

[0059] Optionally, in the embodiment, the predetermined included angle E is 120 degrees. It can be understood that, in the embodiment, the light rays can converge towards the light emitting surface of the chip 10 under the reflection of the reflecting surface 412, thereby enhancing the illumination intensity.

[0060] Referring to Figure 2 Optionally, the lamp bead preparation method further comprises: preparing the substrate 30, and laying the insulating layer 31 on the support layer 32. The electrode layer 20 is arranged on the surface of the insulating layer 31, and the insulating layer 31 can be connected to the support layer 32 in a molding manner; the insulating layer 31 is made of an insulating material, and specifically can be a PET material; and the support layer 32 can be made of a metal material, has relatively large hardness, and can provide stable support for the structure arranged thereon.

[0061] Referring to Figures 3 to 5 Optionally, in the embodiment, the step of preparing the electrode layer 20 comprises: laying a conductive film on the substrate 30, forming the separation groove 23 on the electrode layer 20 through an etching process, the extension path of the separation groove 23 is along the first direction C, and a plurality of separation grooves 23 are arranged at intervals along the second direction D, and the part of the conductive film between two adjacent separation grooves 23 forms the conductive block 21. The conductive film is made of a conductive material, and can be laid on the substrate 30 in a molding manner. It can be understood that, in the embodiment, the chip 10 can be directly electrically mounted on the conductive film, so that the support 20A is not needed, thereby reducing the height of the lamp bead 100; on the one hand, the OD / Pitch value can be reduced, thereby improving the uniformity of light emission; on the other hand, the thickness of the backlight module and the display panel using the lamp bead 100 can be effectively reduced, thereby realizing the lightness and thinness of the display panel and the display.

[0062] Optionally, the conductive film is a copper foil. The copper foil has good conductive performance, and is convenient to bond on the substrate 30, thereby effectively reducing the difficulty of preparing the lamp bead 100.

[0063] Referring to Figure 8 and Figure 11Optionally, in some embodiments, the step of preparing the electrode layer 20 comprises: mounting a bracket 20A on the substrate 30; the bracket 20A corresponds to the chip 10 one by one, and any bracket 20A comprises two conductive blocks 21; the bracket 20A further has a mounting cavity; the mounting cavity has two cavity walls made of transparent material, and any cavity wall is provided with a receiving groove for forming the light blocking layer 41; the step of die bonding further comprises: mounting each chip 10 in the corresponding mounting cavity; and in the step of packaging, the light blocking layer 41 is formed in the receiving groove by means of dispensing. It can be understood that, in the present embodiment, on the one hand, the bracket 20A has relatively large hardness, and can provide protection for the chip 10, the light blocking layer 41 and other structures; on the other hand, the light blocking layer 41 can be set by changing the shape, size and depth of the receiving groove, and has relatively strong flexibility.

[0064] Please refer to Figure 3 , Figures 6 to 8 Optionally, in some embodiments, the chip 10 is a normal chip 10A, and the two electrodes of the chip 10 are electrically connected to the corresponding conductive blocks 21 by gold wires 13. For the convenience of understanding, the two electrodes of the chip 10 are a first electrode and a second electrode respectively, and in these embodiments, the first electrode and the second electrode are connected to the corresponding conductive blocks 21 by one gold wire 13 respectively, so that the chip 10 can be connected to the circuit to realize the light emitting function. Please refer to Figure 4 , Figures 9 to 11 Optionally, in some embodiments, the chip 10 is a flip chip 10B, and is arranged on the adjacent two conductive blocks 21. It can be understood that the first electrode and the second electrode are connected to one conductive block 21 respectively, which can also make the chip 10 connected to the circuit.

[0065] It can be understood that the preparation method of the lamp bead provided by the present application embodiment can install both normal chips 10A and flip chips 10B, has relatively strong flexibility, and can ensure relatively good light emitting intensity and relatively large light emitting area by the foregoing method.

[0066] Please refer to Figure 3 and Figure 4 In the present embodiment, the step of packaging further comprises: filling the fluorescent glue 42 between the adjacent two light blocking layers 41, and covering the chip 10 with the fluorescent glue 42. The fluorescent glue 42 contains fluorescent powder material, and the blue light emitted by the chip 10 can form white light after being filtered by the fluorescent glue 42; in addition, the chip 10 is covered outside by the solidified fluorescent glue 42, which has a certain protection effect on the chip 10. Please refer to Figures 6 to 10 The fluorescent glue 42 is cut to form a light emitting part 421 of the lamp bead 100; the outer surface of the light emitting part 421 is designed as a plane or a predetermined arc, which can realize the corresponding light emitting effect.

[0067] Referring to Figures 6 to 11 The application also provides a lamp bead 100 prepared by the above-mentioned method for preparing a lamp bead. The lamp bead 100 is prepared by referring to the above-mentioned embodiments. Since the lamp bead 100 can be prepared by all the technical solutions of the above-mentioned embodiments, the lamp bead 100 also has all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be repeated here. Specifically, the lamp bead 100 comprises a chip 10, an electricity connecting part 22 and a light blocking part 411. The chip 10 is electrically connected to the electricity connecting part 22 and is configured to emit light. The light blocking part 411 is provided with two and is respectively located at two sides of the chip 10 and is connected to the electricity connecting part 22. The electrode layer 20 can be used to form the electricity connecting part 22, and the light blocking layer 41 can form the light blocking part 411.

[0068] The application also provides a backlight module comprising a plurality of lamp beads 100. The backlight module further comprises a circuit board, and each lamp bead 100 is electrically mounted on the circuit board. It can be understood that the lamp bead 100 used in the backlight module has a larger light emitting range, so that the use of the lamp bead 100 can be reduced under the premise of ensuring the predetermined light intensity, the spacing between two adjacent lamp beads 100 on the circuit board is increased, the OD / Pitch value is reduced, and the uniformity of the backlight module is improved.

[0069] The above is only an optional embodiment of the application and is not used to limit the application. The application can have various changes and modifications for those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the application shall be included in the scope of the claims of the application.

Claims

1. A method for preparing an LED bead, characterized in that, Includes the following steps: Prepare materials, including a substrate (30) and multiple chips (10); An electrode layer (20) is prepared on one side of the substrate (30); wherein the electrode layer (20) includes a plurality of spaced conductive blocks (21), and each conductive block (21) is insulated from the substrate (30); The chip (10) is bonded to the electrode layer (20), and the two electrodes of the chip (10) are electrically connected to two adjacent conductive blocks (21); wherein each chip (10) is arranged at intervals along a first direction (C) and arranged in multiple columns at intervals along a second direction (D); the first direction (C) and the second direction (D) are staggered. Encapsulation: An encapsulation layer (40) is prepared on the conductive block (21); the encapsulation layer (40) includes a plurality of spaced light-blocking layers (41) extending along the second direction (D); the light-blocking layers (41) are provided on two mutually opposite sides of any chip (10), and the other two sides of any chip (10) are exposed to the light-blocking layers (41); and Cutting: The substrate (30), the conductive block (21) and the encapsulation layer (40) are cut along the first direction (C) and the second direction (D) respectively to form a lamp bead (100), the formed lamp bead (100) having three light-emitting surfaces.

2. The method for preparing the lamp bead as described in claim 1, characterized in that, The encapsulation step includes applying adhesive to the conductive block (21) to form the light-blocking layer (41).

3. The method for preparing the lamp bead as described in claim 1, characterized in that, Each of the light-blocking layers (41) has a reflective surface (412) formed on the side facing the corresponding chip (10). The two reflective surfaces (412) located on the same LED bead (100) are arranged in parallel; or the two reflective surfaces (412) located on the same LED bead (100) are arranged at a predetermined angle (E).

4. The method for preparing the lamp bead as described in claim 3, characterized in that, The predetermined included angle (E) is 120 degrees.

5. The method for preparing the lamp bead according to any one of claims 1-4, characterized in that, The steps for preparing the electrode layer (20) include: A conductive film is deposited on the substrate (30), and a partition groove (23) is formed on the conductive film by an etching process. The extension path of the partition groove (23) is along the first direction (C), and a plurality of partition grooves (23) are arranged at intervals along the second direction (D). The portion of the conductive film located between two adjacent partition grooves (23) forms the conductive block (21).

6. The method for preparing the lamp bead according to any one of claims 1-4, characterized in that, The step of preparing the electrode layer (20) includes: mounting a bracket (20A) on the substrate (30); the bracket (20A) corresponds one-to-one with the chip (10), and each bracket (20A) includes two conductive blocks (21); the bracket (20A) has a mounting cavity; the mounting cavity has two cavity walls made of transparent material, and each cavity wall has an accommodating groove for forming the light-blocking layer (41); The die bonding step further includes: mounting each of the chips (10) into the corresponding mounting cavity; In the encapsulation step, the light-blocking layer (41) is formed in the receiving groove by dispensing adhesive.

7. The method for preparing the lamp bead according to any one of claims 1-4, characterized in that, The chip (10) is a standard chip (10A), and the two electrodes of the chip (10) are electrically connected to the corresponding conductive blocks (21) through gold wires (13); or, the chip (10) is a flip chip (10B) and is mounted on two adjacent conductive blocks (21).

8. The method for preparing the lamp bead according to any one of claims 1-4, characterized in that, The packaging step further includes: Fill with fluorescent adhesive (42) between two adjacent light-blocking layers (41) and make the fluorescent adhesive (42) cover the chip (10).

9. A type of LED bead (100), characterized in that, The lamp bead (100) is manufactured by the lamp bead manufacturing method according to any one of claims 1-8; the lamp bead (100) includes the chip (10), the power receiving part (22) and the light blocking part (411); the chip (10) is electrically connected to the power receiving part (22) and configured to emit light; two light blocking parts (411) are provided and are respectively located on both sides of the chip (10) and connected to the power receiving part (22); The electrode layer (20) can be formed into the electrical contact portion (22) through the cutting step, and the light-blocking layer (41) can be formed into the light-blocking portion (411) through the cutting step.

10. A backlight module, characterized in that, The backlight module includes multiple LED beads (100) as described in claim 9, and also includes a circuit board, wherein each LED bead (100) is electrically mounted on the circuit board.

Images