Virtual pixel four-in-one LED lamp bead, preparation method thereof and display screen

Abstract

The invention discloses a virtual pixel four-in-one LED lamp bead, a preparation method of the virtual pixel four-in-one LED lamp bead and a display screen. The virtual pixel four-in-one LED lamp bead comprises a substrate; the light-emitting chips are arranged on the front surface of the substrate, the light-emitting chips comprise first light-emitting chips and second light-emitting chips, the first light-emitting chips comprise a first red light chip, a first green light chip and a first blue light chip, and the second light-emitting chips comprise a second red light chip, a second green light chip and a second blue light chip; the first light-emitting chips and the second light-emitting chips are matched in a crossed mode to form at least four pixel points, and the first light-emitting chips and the second light-emitting chips are arranged in a non-diagonal mode. The pins are arranged on the back surface of the substrate, and the pins are connected with the electrodes of the light-emitting chips; and the packaging adhesive layer wraps the substrate and the light-emitting chip. By implementing the virtual pixel four-in-one LED lamp bead provided by the invention, the packaging process difficulty can be reduced, the use cost of a chip is reduced, and meanwhile, the yield of a product is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of LEDs, and in particular to a virtual pixel four-in-one LED lamp bead, a preparation method thereof, and a display screen. Background Art

[0002] At present, the domestic traditional LED display application market has basically matured and tended to be saturated, and the competition for LED display lamp beads, the key components of the display, has become increasingly fierce. In order to seize market share and improve product competitive advantages, various packaging manufacturers have made great efforts to improve material consumption, manufacturing costs, and process improvements on the manufacturing side. At the same time, they have upgraded and transformed their products in terms of structure upgrades and performance enhancements on the product design side.

[0003] In terms of CHIP type lamp beads, traditional surface mount lamp beads are basically one pixel, including three chips of red, green and blue. Due to the impact of the emerging COB display screen packaging form, the market share of two-in-one and four-in-one Mini package lamp beads of discrete devices has gradually shrunk, and various packaging factories have gradually reduced or cancelled the investment in all-in-one products. However, all-in-one discrete devices still have many advantages over COB in many aspects, and are still irreplaceable in many application products. At present, the market of four-in-one is mainly based on CHIP type lamp beads, among which the MIP packaging form with flip chip is relatively single lamp and COB, and it is a transitional product between the two and still has certain advantages.

[0004] The 4-in-1 Mini-LED lamp bead is a carrier that combines functional areas. It uses integrated packaging technology (Integrated Mounted Devices, abbreviated as: IMD), that is, it uses 4-in-1 array packaging technology to package 4 groups of RGB chips, that is, a single lamp contains four pixels. The 4-in-1 Mini-LED has great advantages for screen manufacturers. However, at this stage, whether the 4-in-1 Mini-LED is flip-chip or face-mounted, it is arranged in a matrix of 4 groups of RGB chips. For small-sized 4-in-1 products, the space of the functional area is small, the operation is difficult, and some defects are inevitable. In addition, due to the characteristics of the 4-in-1, the defect of one chip will cause the entire lamp bead to become a defective product, resulting in a large cost loss. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a virtual pixel four-in-one LED lamp bead and its preparation method and display screen. The packaging process of the virtual pixel four-in-one LED lamp bead is low in difficulty, the chip use cost is low, and the product yield is high.

[0006] In order to solve the above technical problems, the first aspect of the present invention provides a virtual pixel four-in-one LED lamp bead, comprising:

[0007] substrate;

[0008] A light-emitting chip is arranged on the front side of the substrate, the light-emitting chip includes a first light-emitting chip and a second light-emitting chip, the first light-emitting chip includes a first red light chip, a first green light chip and a first blue light chip, the second light-emitting chip includes a second red light chip, a second green light chip and a second blue light chip, the first light-emitting chip and the second light-emitting chip are cross-matched to form at least four pixel points, and the first light-emitting chip and the second light-emitting chip are non-diagonally arranged;

[0009] A pin disposed on the back side of the substrate, the pin being connected to an electrode of the light emitting chip;

[0010] A packaging adhesive layer wrapping the substrate and the light-emitting chip.

[0011] As an improvement of the above solution, the first red light chip and the second red light chip are on the same straight line, and the connection line L1 between the first red light chip and the second red light chip is located between the first green light chip and the second green light chip, and between the first blue light chip and the second blue light chip;

[0012] The connection line between the first green chip and the second green chip is L2, the connection line between the first blue chip and the second blue chip is L3, and L2 and L3 form an intersection.

[0013] As an improvement of the above solution, the intersection point formed by L2 and L3 is located on L1.

[0014] As an improvement of the above solution, the lengths of the first red light chip, the first green light chip, the first blue light chip, and the second red light chip along the first direction are greater than their widths along the second direction;

[0015] The length of the second green chip and the second blue chip along the first direction is smaller than the width along the second direction.

[0016] As an improvement of the above solution, the light-emitting chip also includes a third light-emitting chip. The first light-emitting chip, the second light-emitting chip and the third light-emitting chip are cross-matched to form at least four pixel points. The third light-emitting chip is one of a red light chip, a green light chip and a blue light chip.

[0017] As an improvement of the above solution, the third light-emitting chip is a third red light chip, the first red light chip, the second red light chip, and the third red light chip are on the same straight line, and a line L4 connecting the first red light chip, the second red light chip, and the third red light chip is located between the first green light chip and the second green light chip, and between the first blue light chip and the second blue light chip;

[0018] The connection line between the first green chip and the second green chip is L5, and the connection line between the first blue chip and the second blue chip is L6, and L5 and L6 form an intersection.

[0019] As an improvement of the above solution, the intersection point formed by L5 and L6 is located on L4.

[0020] As an improvement of the above solution, the lengths of the first red light chip, the second red light chip, and the third red light chip along the first direction are smaller than their widths along the second direction;

[0021] The lengths of the first green chip, the first blue chip, the second green chip, and the second blue chip along the first direction are greater than their widths along the second direction.

[0022] The second aspect of the present invention further provides a method for preparing the virtual pixel four-in-one LED lamp bead, comprising:

[0023] Fixing the light-emitting chip on the front side of the substrate, arranging the red light chip, the green light chip and the blue light chip to form at least four pixel points;

[0024] Forming leads on the back side of the substrate and connecting the leads to electrodes of the light emitting chip;

[0025] The surfaces of the substrate and the light-emitting chip are wrapped to form an encapsulation adhesive layer.

[0026] The third aspect of the present invention also provides a display screen, comprising the virtual pixel four-in-one LED lamp bead as described in item.

[0027] The implementation of the present invention has the following beneficial effects:

[0028] In the present invention, by cross-coordinating the red light chip, green light chip and blue light chip in the first light-emitting chip and the second light-emitting chip, a virtual four-pixel point can be formed, thereby achieving the technical effect of reducing the chip usage cost and optimizing the lamp bead structure. Moreover, reducing the number of chips can significantly increase the space of the functional area, reduce the difficulty of the packaging process, and is conducive to improving the yield of the virtual pixel four-in-one LED lamp beads, especially the virtual pixel four-in-one Mini-LED lamp beads. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 : Schematic diagram of the structure of the actual pixel four-in-one LED lamp bead in the prior art;

[0030] Figure 2 : The overall structure diagram of the actual pixel four-in-one LED lamp bead in the prior art;

[0031] Figure 3 : The electrode connection relationship of the light-emitting chip of the actual pixel four-in-one LED lamp bead in the prior art;

[0032] Figure 4 : The back structure diagram of the light-emitting chip of the actual pixel four-in-one LED lamp bead in the prior art;

[0033] Figure 5 : Distribution diagram of through holes of the light-emitting chip of the actual pixel four-in-one LED lamp bead in the prior art;

[0034] Figure 6 : A front perspective pin diagram of the light-emitting chip of the actual four-in-one pixel LED lamp bead in the prior art;

[0035] Figure 7 : A schematic diagram of the structure of a virtual pixel four-in-one LED lamp bead in the present invention;

[0036] Figure 8 : The overall structure diagram of a virtual pixel four-in-one LED lamp bead in the present invention;

[0037] Fig. 9 : The electrode connection relationship of the light-emitting chip of a virtual pixel four-in-one LED lamp bead in the present invention;

[0038] Fig.10 : A back structural diagram of a light-emitting chip of a virtual pixel four-in-one LED lamp bead in the present invention;

[0039] Fig.11 : A front perspective pin diagram of a light-emitting chip of a virtual pixel four-in-one LED lamp bead in the present invention;

[0040] Fig.12 : A distribution diagram of through holes of a light-emitting chip of a virtual pixel four-in-one LED lamp bead in the present invention;

[0041] Fig.13 : A schematic diagram of the structure of another virtual pixel four-in-one LED lamp bead in the present invention;

[0042] Fig.14 : Overall structure diagram of another virtual pixel four-in-one LED lamp bead in the present invention;

[0043] Fig.15 : Another electrode connection relationship of the light-emitting chip of the virtual pixel four-in-one LED lamp bead in the present invention;

[0044] Fig.16 : A back structural diagram of another light-emitting chip of a virtual pixel four-in-one LED lamp bead in the present invention;

[0045] Fig.17 : A front perspective pin diagram of another light-emitting chip of a virtual pixel four-in-one LED lamp bead in the present invention;

[0046] Fig.18: Distribution diagram of through holes of another light-emitting chip of a virtual pixel four-in-one LED lamp bead in the present invention.

[0047] Reference numerals:

[0048] 1-substrate; 2-first light-emitting chip; 21-first red light chip; 22-first green light chip; 23-first blue light chip; 3-second light-emitting chip; 31-second red light chip; 32-second green light chip; 33-second blue light chip; 4-first electrode; 5-second electrode; 6-first pin; 7-second pin; 8-through hole; 9-third light-emitting chip; 91-third red light chip. DETAILED DESCRIPTION

[0049] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described in detail with specific embodiments below.

[0050] The four-in-one Mini-LED has the following characteristics: 1. It has the display performance and robustness advantages of COB products, and avoids the difficulties of "mass transfer", thereby improving the testing efficiency of the packaging factory and the patch efficiency of the screen factory. At the same time, compared with COB products, the four-in-one lamp beads are easier to replace and repair when they fail in application, reducing maintenance costs; 2. The screen factory adopts conventional welding technology, and the four-in-one product inherits the advantages of low cost, maturity, and easy maintenance of a single bad lamp of the surface mount technology, which improves the thrust of the Mini-LED lamp beads; 3. While controlling costs, the screen factory not only meets the needs of more sophisticated displays, but also avoids the requirements of extreme geometric dimensions, so that smaller pitch products can be made under ordinary processes to meet the preparation of four-in-one Mini-LED; 4. The four-in-one pixel package reduces the "welding operation scale" per unit area of ​​the "ultra-small pitch LED display", and combined with the use of smaller Mini-LED crystal particles, it is more suitable for the pursuit of "smaller and smaller" pitch indicators.

[0051] The 4-in-1 Mini-LED adopts the integrated mounting device (IMD) packaging technology, that is, the 4-in-1 array packaging technology is adopted, and the small units composed of 2 lamp beads are used horizontally and vertically respectively, and each lamp bead is still packaged with RGB three-color chips. Figure 1As shown, the positive electrodes (or negative electrodes) of the two lamp beads arranged horizontally are connected together and connected to the pins of the same polarity set on the back of the substrate 1, and the negative electrodes (or positive electrodes) of the red light chips in the two lamp beads arranged vertically are connected together and connected to the pins of the same polarity set on the back of the substrate 1, the negative electrodes (or positive electrodes) of the green light chips in the two lamp beads arranged vertically are connected together and connected to the pins of the same polarity set on the back of the substrate 1, and the negative electrodes (or positive electrodes) of the blue light chips in the two lamp beads arranged vertically are connected together and connected to the pins of the same polarity set on the back of the substrate 1, as shown. Figure 2-Figure 4 As shown, the electrodes of the light-emitting chip can be connected to the pins by setting a through hole 8 on the substrate 1, as shown in FIG. Figure 5 and Figure 6 If one chip in this structure is defective, the entire LED lamp bead will be defective, increasing the defect rate of virtual pixel four-in-one LED lamp beads, especially small pitch virtual pixel four-in-one LED lamp beads.

[0052] To solve the above problems, the first aspect of the present invention provides a virtual pixel four-in-one LED lamp bead, such as Figure 7-Figure 12 As shown, including:

[0053] A substrate 1, a light-emitting chip disposed on the front of the substrate 1, pins disposed on the back of the substrate 1, the pins being connected to the electrodes of the light-emitting chip; and a packaging adhesive layer wrapping the substrate 1 and the light-emitting chip. It can be understood that the light-emitting chip is fixed on the substrate 1 by flip-chip mounting, and the substrate 1 can be a BT board or a PCB board commonly used in the art, but is not limited thereto.

[0054] Wherein, the light-emitting chip includes a first light-emitting chip 2 and a second light-emitting chip 3, the first light-emitting chip 2 includes a first red chip 21, a first green chip 22 and a first blue chip 23, the second light-emitting chip 3 includes a second red chip 31, a second green chip 32 and a second blue chip 33, the first light-emitting chip 2 and the second light-emitting chip 3 are cross-matched to form at least four pixel points, and the first light-emitting chip 2 and the second light-emitting chip 3 are non-diagonally arranged. In the present invention, by cross-matching the first red chip 21, the first green chip 22, the first blue chip 23, the second red chip 31, the second green chip 32 and the second blue chip 33, a virtual four-pixel point can be formed, achieving the technical effect of reducing the chip use cost and optimizing the lamp bead structure, and reducing the number of chips can significantly increase the space of the functional area, reduce the difficulty of the packaging process, and help improve the yield of the virtual pixel four-in-one LED lamp bead, especially the virtual pixel four-in-one Mini-LED lamp bead.

[0055] Preferably, see Figure 7The first red light chip 21 and the second red light chip 31 are on the same straight line, and the connection line L1 of the first red light chip 21 and the second red light chip 31 is located between the first green light chip 22 and the second green light chip 32, and between the first blue light chip 23 and the second blue light chip 33; the connection line between the first green light chip 22 and the second green light chip 32 is L2, the connection line between the first blue light chip 23 and the second blue light chip 33 is L3, and the L2 and L3 form an intersection point. At this time, it is convenient to form four virtual pixel points, and the LED lamp beads can have good color rendering uniformity and form a good pixel color rendering effect.

[0056] Further, the intersection point formed by the L2 and L3 is located on the L1, so that the first red light chip 21, the second green light chip 32 and the second blue light chip 33 form an equilateral triangle. The L1, L2, and L3 are the three midlines of the equilateral triangle, and the L1 is also located on the central axis of the substrate 1. The first green light chip 22 and the first blue light chip 23 are symmetrically arranged with respect to the L1, optimizing the color mixing path of red, green, and blue, achieving a more uniform and soft light output, and significantly improving the luminous efficiency of the LED. Exemplarily, the first light-emitting chip 2 is arranged in a "pin" shape, and the second light-emitting chip 3 is arranged horizontally in a "one" shape and is located below the first light-emitting chip 2. That is, the first red light chip 21, the first green light chip 22, and the first blue light chip 23 respectively correspond to the three "mouths" of the "pin", and the second red light chip 31, the second green light chip 32, and the second blue light chip 33 are arranged horizontally in sequence in a "one" shape.

[0057] Furthermore, the length a1 of the first red light chip 21, the first green light chip 22, the first blue light chip 23, and the second red light chip 31 along the first direction is greater than the width b1 along the second direction; the length a2 of the second green light chip 32 and the second blue light chip 33 along the first direction is less than the width b2 along the second direction, which is not only beneficial to improving the luminous uniformity of the LED lamp beads, but also helps to evenly distribute heat and effectively dissipate heat, improve the thermal stability of the lamp beads, and can also increase the distance between adjacent light-emitting chips as much as possible to reduce the operation difficulty of the light-emitting chips. It should be noted that the first direction and the second direction in the present invention are described based on the direction of the drawing vision, that is, the first direction is the horizontal direction of the substrate 1, and the second direction is the vertical direction of the substrate 1.

[0058] Furthermore, the width of the substrate 1 is H, the length is D, the distance between the first red chip 21 and the second red chip 31 is H1, H1=(1 / 3~2 / 3)H, the vertical distance between the first light-emitting chip 2 and the second light-emitting chip 3 is H2, H2=(1 / 3~2 / 3)H. In the first light-emitting chip 2, the distance between the first green chip 22 and the first blue chip 23 is D1, D1=(1 / 3~2 / 3)D, the second red chip 31, the second green chip 32, and the second blue chip 33 are arranged at equal intervals, and the horizontal distance between the second green chip 32 and the second red chip 31 is D2, D2=(1 / 3~2 / 3)D. By controlling the distance between the red chip, the green chip, and the blue chip in the light-emitting unit, the display color consistency of different light-emitting unit combinations is guaranteed, the difficulty of operation is reduced, and the good overall display effect and reliability of the display screen can be guaranteed, so that the color temperature is between 6400K and 6900K.

[0059] Specifically, Figure 8 and Fig. 9 As shown, the first electrodes 4 of the first red chip 21, the first green chip 22 and the first blue chip 23 are connected to form a first common electrode, and the first electrodes 4 of the second red chip 31, the second green chip 32 and the second blue chip 33 are connected to form a second common electrode. The electroplating lead structure of the light-emitting chip is adjusted, and the effect of four pixels can be achieved by using two groups of RGB light-emitting chips, and multiple light-emitting chips work independently. When one of the light-emitting chips is damaged, it will not cause the entire LED lamp bead to be unusable, and it is easy to replace and repair, thereby improving the yield of the virtual pixel four-in-one LED lamp bead and reducing the cost. It can be understood that the polarity of the first electrode 4 and the second electrode 5 is different, the first electrode 4 is the positive electrode of the chip, and the second electrode 5 is the negative electrode of the chip, or the first electrode 4 is the negative electrode of the chip, and the second electrode 5 is the positive electrode of the chip.

[0060] Furthermore, the back side of the substrate 1 is provided with pins, such as Fig.10 As shown, the pins include two first pins 6 and multiple second pins 7, the first common electrode and the second common electrode are respectively connected to the two first pins 6, and the second electrodes 5 of the first red light chip 21, the first green light chip 22, the first blue light chip 23, the second red light chip 31, the second green light chip 32 and the second blue light chip 33 are respectively connected to the multiple second pins 7, wherein the polarity of the first pin 6 is different from the polarity of the second pin 7, the first pin 6 is the same as the polarity of the first electrode 4, and the second pin 7 is the same as the polarity of the second electrode 5.

[0061] Due to the above connection method, the LED lamp bead has two first electrodes 4 (first common electrode and second common electrode) and six second electrodes 5. Correspondingly, the LED lamp bead has two first pins 6 and six second pins 7. Fig.11 As shown, it includes a first first pin C12, a second first pin C21, a first second pin R1, a second second pin B1, a third second pin G1, a fourth second pin R2, a fifth second pin B2, and a sixth second pin G2, so that the two first electrodes 4 of the LED lamp bead are respectively connected to the first first pin C12 and the second first pin C21 of the same polarity, and the six second electrodes 5 of the LED lamp bead are respectively connected to the first second pin R1, the second second pin B1, the third second pin G1, the fourth second pin R2, the fifth second pin B2, and the sixth second pin G2 of the same polarity. Specifically, as Figure 8 and Fig.12 As shown, the substrate 1 is provided with a through hole 8 penetrating the substrate 1, so that the first common electrode and the second common electrode are respectively connected to the two first pins 6 through the through hole 8, and the second electrode 5 is respectively connected to the plurality of second pins 7 through the through hole 8. It can be understood that the number of the through holes 8 corresponds to the number of the pins, so as to facilitate the electrical connection between the electrodes and the pins of the light-emitting chip. Of course, the through hole 8 can also be a solid conductive column, and the through hole 8 is not specifically limited in this application.

[0062] In other embodiments, Figure 13-Figure 18 As shown, the light-emitting chip also includes a third light-emitting chip 9. The first light-emitting chip 2, the second light-emitting chip 3 and the third light-emitting chip 9 are cross-matched to form at least four pixel points. The third light-emitting chip 9 is one of a red light chip, a green light chip and a blue light chip.

[0063] The following description will be made by taking the third light emitting chip 9 as the third red light chip 91 as an example.

[0064] See also Fig.13, the first red light chip 21, the second red light chip 31, and the third red light chip 91 are on the same straight line, and the connection line L4 of the first red light chip 21, the second red light chip 31, and the third red light chip 91 is located between the first green light chip 22 and the second green light chip 32, between the first blue light chip 23 and the second blue light chip 33, the connection line between the first green light chip 22 and the second green light chip 32 is L5, and the connection line between the first blue light chip 23 and the second blue light chip 33 is L6, and L5 and L6 form an intersection. At this time, the uniformity of the RGB combination pixel color matching can be optimized, with good color rendering uniformity, forming a good pixel color rendering effect. More importantly, through the coordinated use of the first light-emitting chip 2, the second light-emitting chip 3 and the third red light chip 91, the light-emitting chips are evenly distributed on the substrate, avoiding the setting of no light-emitting chips at the corners, and further improving the overall uniformity and brightness of the lamp beads.

[0065] Furthermore, the intersection formed by L5 and L6 is located on L4. In some embodiments, L4 is located on the horizontal central axis of the substrate 1, and L4 overlaps with the midline of L5 and L6, so that the first green chip 22 and the second blue chip 33 are symmetrically arranged about L4, and the first blue chip 23 and the second green chip 32 are symmetrically arranged about L4, which optimizes the color mixing path of red, green and blue, realizes a more uniform and soft light output, and significantly improves the luminous efficiency of the LED. In addition, it is convenient to set up the circuit of pins, bonding wires, etc., and reduces the difficulty of operation. Exemplarily, the first light-emitting chip 2, the second light-emitting chip 3 and the third light-emitting chip 9 are arranged in an "8" shape, wherein the third light-emitting chip 9, the first light-emitting chip 2, and the two chips of the same color as the third light-emitting chip 9 among the second light-emitting chip 3 are arranged in an "I" shape, and the remaining chips in the first light-emitting chip 2 and the second light-emitting chip 3 are arranged in an "I" shape, that is, the first red light chip 21, the first green light chip 22, the first blue light chip 23, the second red light chip 31, the second green light chip 32, the second blue light chip 33 and the third red light chip 91 are equivalent to the 7 strokes of the number "8". Specifically, the first red light chip 21, the second red light chip 31 and the third red light chip 91 are arranged in an "I" shape, the first green light chip 22 and the first blue light chip 23 are arranged horizontally in an "I" shape, and the second green light chip 32 and the second blue light chip 33 are arranged horizontally in an "I" shape, so that the light-emitting chips are arranged in a flat "8" shape.

[0066] Furthermore, the length a3 of the first red light chip 21, the second red light chip 31, and the third red light chip 91 along the first direction is smaller than the width b3 along the second direction; the length a4 of the first green light chip 22, the first blue light chip 23, the second green light chip 32, and the second blue light chip 33 along the first direction is larger than the width b4 along the second direction. The light-emitting angle of the red light chip is smaller than that of the blue-green light chip. The first red light chip 21, the second red light chip 31, and the third red light chip 91 are vertically arranged, and the first green light chip 22, the first blue light chip 23, the second green light chip 32, and the second blue light chip 33 increase the light-emitting brightness and reduce the color temperature deviation on the basis of forming at least four pixel points. In addition, the gap between the first red light chip 21, the second red light chip 31, and the third red light chip 91 is increased, which helps to reduce the risk of metal migration, promote uniform distribution of heat and effective heat dissipation, thereby improving the thermal stability and life of the LED lamp beads, and making the color temperature between 6400K and 7000K.

[0067] Furthermore, the first red light chip 21, the second red light chip 31 and the third red light chip 91 are arranged at equal intervals, and the horizontal distance between the first red light chip 21 and the second red light chip 31 is D3, D3=(1 / 3~2 / 3)D; the vertical distance between the third red light chip 91 and the first green light chip 22 is H3, H3=(1 / 3~2 / 3)H. By controlling the distance between the red light chip, the green light chip and the blue light chip in the light-emitting unit, the accuracy of the position of each light-emitting pixel and the uniformity of the overall distribution of the lamp beads can be guaranteed, so that the overall light-emitting display effect is better.

[0068] Specifically, Fig.14 and Fig.15 As shown, the first electrodes 4 of the first light-emitting chip 2, the second light-emitting chip 3 and the third light-emitting chip 9 are connected to form a common electrode. In this solution, the first light-emitting chip 2, the second light-emitting chip and the third light-emitting chip 9 are set with a common electrode, and the electroplating lead structure of the light-emitting chip is adjusted. Not only can two groups of RGB light-emitting chips be used to achieve the effect of four pixels, but also multiple light-emitting chips can work independently. When one of the light-emitting chips is damaged, it will not cause the entire LED lamp bead to be unusable, and it is easy to replace and repair, thereby improving the yield of the virtual pixel four-in-one LED lamp bead and reducing the cost. It can be understood that the polarity of the first electrode 4 and the second electrode 5 is different. The first electrode 4 is the positive electrode of the chip, and the second electrode 5 is the negative electrode of the chip, or the first electrode 4 is the negative electrode of the chip, and the second electrode 5 is the positive electrode of the chip.

[0069] Furthermore, the back side of the substrate 1 is provided with pins, such as Fig.16As shown, the pins include a first pin 6 and a plurality of second pins 7, the common electrode formed by connecting the first electrodes 4 of the first light-emitting chip 2, the second light-emitting chip 3 and the third light-emitting chip 9 is connected to the first pin 6, and the second electrodes 5 of the first light-emitting chip 2, the second light-emitting chip 3 and the third light-emitting chip 9 are respectively connected to the plurality of second pins 7, so that the plurality of light-emitting chips can act independently, and the arrangement density of the pins is reduced, which has the advantage of simple wiring. Among them, the polarity of the first pin 6 is different from the polarity of the second pin 7, the first pin 6 is the same as the polarity of the first electrode 4, and the second pin 7 is the same as the polarity of the second electrode 5.

[0070] Due to the above connection method, the LED lamp bead has a first electrode 4 (common electrode) and seven second electrodes 5. Correspondingly, the LED lamp bead has a first pin 6 and six second pins 7. Fig.17 As shown, it includes a first pin C12, a first second pin R1, a second second pin B1, a third second pin G1, a fourth second pin R2, a fifth second pin B2, a sixth second pin G2, and a seventh second pin R3, so that the first electrode 4 of the LED lamp bead is connected to the first pin C12 of the same polarity, and the seven second electrodes 5 of the LED lamp bead are connected to the first second pin R1, the second second pin B1, the third second pin G1, the fourth second pin R2, the fifth second pin B2, the sixth second pin G2, and the seventh second pin R3 of the same polarity. Specifically, as Fig.14 and Fig.18 As shown, the substrate 1 is provided with a through hole 8 penetrating the substrate 1, so that the common electrode is connected to the first pin 6 through the through hole 8, and the second electrode 5 of the first light-emitting chip 2, the second light-emitting chip 3, and the third light-emitting chip 9 is respectively connected to a plurality of second pins 7 through the through hole 8. It can be understood that the number of the through holes 8 corresponds to the number of pins, so as to facilitate the electrical connection between the electrodes and the pins of the light-emitting chip. Of course, the through hole 8 can also be a solid conductive column, and the through hole 8 is not specifically limited in this application.

[0071] Optionally, the encapsulation layer can be used to protect the light-emitting chip from moisture, dust, chemicals, etc. in the external environment, and at the same time seal and cover the electrodes and leads in the light-emitting chip to ensure the reliability of the electrical connection, thereby extending the service life of the LED lamp bead. The encapsulation glue in the encapsulation layer has multiple options, including but not limited to epoxy resin, silicone resin, and silica gel, and the encapsulation glue can also be added with silicon dioxide, silica diffusion powder or phosphors, wherein the phosphors can be nitrides, silicates, potassium chromium, lutetium chromium, etc. The present application does not specifically limit the material of the encapsulation layer.

[0072] Accordingly, the present invention further provides a method for preparing a virtual pixel four-in-one LED lamp bead, including:

[0073] (1) Fix light-emitting chips on the front surface of the substrate 1, and arrange red light chips, green light chips, and blue light chips to form at least four pixel points;

[0074] (2) Form pins on the back surface of the substrate 1, and connect the pins to the electrodes of the light-emitting chips;

[0075] (3) Wrap and form an encapsulation glue layer on the surfaces of the substrate 1 and the light-emitting chips.

[0076] Accordingly, the present invention further provides a display screen, including the virtual pixel four-in-one LED lamp bead described above.

[0077] The following further illustrates the present invention with specific embodiments:

[0078] Embodiment 1

[0079] This embodiment provides a virtual pixel four-in-one LED lamp bead, the structure of which is as Figure 7 shown, including:

[0080] A substrate; light-emitting chips arranged on the front surface of the substrate; pins arranged on the back surface of the substrate, the pins being connected to the electrodes of the light-emitting chips; an encapsulation glue layer wrapping the substrate and the light-emitting chips.

[0081] Among them, the light-emitting chips include a first light-emitting chip and a second light-emitting chip. The first light-emitting chip includes a first red light chip, a first green light chip, and a first blue light chip. The second light-emitting chip includes a second red light chip, a second green light chip, and a second blue light chip. The first red light chip and the second red light chip are on the same straight line, and the connection line L1 between the first red light chip and the second red light chip is located between the first green light chip and the second green light chip, and between the first blue light chip and the second blue light chip. The connection line between the first green light chip and the second green light chip is L2, and the connection line between the first blue light chip and the second blue light chip is L3. The intersection point formed by L2 and L3 is located on L1, that is, the first light-emitting chip is arranged in a "pin" shape, and the second light-emitting chip is arranged horizontally in a "one" shape and is located below the first light-emitting chip, so that the first red light chip, the second green light chip, and the second blue light chip form an equilateral triangle, and cross-matching forms four pixel points.

[0082] The length of the first red chip, the first green chip, the first blue chip, and the second red chip along the first direction is greater than the width along the second direction; the length of the second green chip and the second blue chip along the first direction is less than the width along the second direction. The width H of the substrate is 1300 μm, the length D is 1300 μm, the distance H1 between the first red chip and the second red chip is 870 μm, the vertical distance H2 between the first light-emitting chip and the second light-emitting chip is 435 μm, the distance D1 between the first green chip and the first blue chip is 435 μm, the second red chip, the second green chip, and the second blue chip are arranged at equal intervals, and the horizontal distance D2 between the second green chip and the second red chip is 435 μm.

[0083] The anodes of the first red light chip, the first green light chip and the first blue light chip are connected to form a first common anode, the anodes of the second red light chip, the second green light chip and the second blue light chip are connected to form a second anode, the first common anode and the second common anode are respectively connected to two anode pins, and the cathodes of the first red light chip, the first green light chip, the first blue light chip, the second red light chip, the second green light chip and the second blue light chip are respectively connected to multiple cathode pins.

[0084] Example 2

[0085] This embodiment provides a virtual pixel four-in-one LED lamp bead, and its structure is as follows Fig.13 As shown, including:

[0086] A substrate; a light-emitting chip arranged on the front side of the substrate; pins arranged on the back side of the substrate, the pins being connected to the electrodes of the light-emitting chip; and a packaging adhesive layer wrapping the substrate and the light-emitting chip.

[0087] Among them, the light-emitting chip includes a first light-emitting chip, a second light-emitting chip and a third light-emitting chip, the first light-emitting chip includes a first red light chip, a first green light chip and a first blue light chip, the second light-emitting chip includes a second red light chip, a second green light chip and a second blue light chip, and the third light-emitting chip is a third red light chip. The first red light chip, the second red light chip, and the third red light chip are on the same straight line, and a line L4 connecting the first red light chip, the second red light chip, and the third red light chip is located between the first green light chip and the second green light chip, between the first blue light chip and the second blue light chip, a line between the first green light chip and the second green light chip is L5, a line between the first blue light chip and the second blue light chip is L6, L5 and L6 form an intersection, and the intersection formed by L5 and L6 is located on L4, and the whole is arranged in an "8" shape, and the first red light chip, the first green light chip, the first blue light chip, the second red light chip, the second green light chip, the second blue light chip, and the third red light chip are equivalent to the 7 strokes of the number "8", so that the first light-emitting chip, the second light-emitting chip, and the third light-emitting chip are cross-matched to form four pixel points.

[0088] The length of the first red chip, the second red chip, and the third red chip along the first direction is less than the width along the second direction; the length of the first green chip, the first blue chip, the second green chip, and the second blue chip along the first direction is greater than the width along the second direction. The width H of the substrate is 1300 μm, the length D is 1300 μm, the first red chip, the second red chip, and the third red chip are arranged at equal intervals, the horizontal distance D3 between the first red chip and the second red chip is 435 μm, and the vertical distance H3 between the third red chip and the first green chip is 435 μm.

[0089] The anodes of the first light-emitting chip, the second light-emitting chip and the third light-emitting chip are connected to form a common anode and then connected to the common anode pin, and the cathodes of the first light-emitting chip, the second light-emitting chip and the third light-emitting chip are connected to multiple cathode pins respectively.

[0090] Example 3

[0091] This embodiment provides a virtual pixel four-in-one LED lamp bead, which is basically the same as the embodiment 1, except that:

[0092] The intersection point formed by L2 and L3 is not located on L1;

[0093] The distance H1 between the first red light chip and the second red light chip is 870 μm, the vertical distance H2 between the first light-emitting chip and the second light-emitting chip is 435 μm, the distance D1 between the first green light chip and the first blue light chip is 435 μm, the second red light chip, the second green light chip, and the second blue light chip are arranged at equal intervals, and the horizontal distance D2 between the second green light chip 32 and the second red light chip 31 is 435 μm.

[0094] Example 4

[0095] This embodiment provides a virtual pixel four-in-one LED lamp bead, which is basically the same as the embodiment 1, except that:

[0096] The lengths of the first red chip, the first green chip, the first blue chip, and the second red chip along the first direction are greater than their widths along the second direction; the lengths of the second green chip and the second blue chip along the first direction are greater than their widths along the second direction.

[0097] Example 5

[0098] This embodiment provides a virtual pixel four-in-one LED lamp bead, which is basically the same as the embodiment 2, except that:

[0099] The lengths of the first red light chip, the second red light chip, and the third red light chip along the first direction are greater than their widths along the second direction;

[0100] The lengths of the first green chip, the first blue chip, the second green chip, and the second blue chip along the first direction are greater than their widths along the second direction.

[0101] Control group

[0102] by Figure 1 The four-in-one LED lamp beads shown are the control group, that is, in the control group, the light-emitting chips include a first light-emitting chip, a second light-emitting chip, a third light-emitting chip, and a fourth light-emitting chip, all of which include a red light chip, a green light chip, and a blue light chip.

[0103] A P0.7mm pitch display screen of the same size was attached to each of the LED lamp beads obtained in the embodiment and the control group, and the same refresh frequency and test current were set. The maximum brightness, maximum contrast, and grayscale of the display screens of the embodiment and the control example under overall white balance were tested, wherein the maximum brightness, maximum contrast, and grayscale were measured according to the methods specified in 5.2.1, 5.2.3, and 5.3.3 of SJ / T 11141-2017 "General Specification for LED Display Screens" and SJ / T 11281-2017 "Test Methods for Light Emitting Diode (LED) Display Screens".

[0104] The test results are shown in Table 1.

[0105] Table 1 Performance test results of LED display screens obtained in the embodiment and control group

[0106]

[0107]

[0108] In this application, a combination of 2 groups of RGB chips or 2 groups of RGB chips and one red / green / blue light chip is used, which can be cross-coordinated to generate at least four pixel points to obtain virtual pixel four-in-one LED lamp beads. Compared with traditional four-in-one LED lamp beads, the virtual pixel four-in-one LED lamp beads in this application can reduce the number of chips used, increase the available space, and thus reduce the difficulty of packaging. At the same time, it maintains the maximum brightness, best contrast and grayscale inherent in the four-in-one lamp beads, has good color saturation and color uniformity, improves product quality and yield, and comprehensively achieves cost reduction.

[0109] The above disclosure is only a preferred embodiment of the present invention, which certainly cannot be used to limit the scope of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope of the present invention.

Claims

1. A virtual pixel four-in-one LED lamp bead, characterized in that: include: substrate; A light-emitting chip is arranged on the front side of the substrate, the light-emitting chip includes a first light-emitting chip and a second light-emitting chip, the first light-emitting chip includes a first red light chip, a first green light chip and a first blue light chip, the second light-emitting chip includes a second red light chip, a second green light chip and a second blue light chip, the first light-emitting chip and the second light-emitting chip are cross-matched to form at least four pixel points, and the first light-emitting chip and the second light-emitting chip are non-diagonally arranged; A pin disposed on the back side of the substrate, the pin being connected to an electrode of the light emitting chip; A packaging adhesive layer wrapping the substrate and the light-emitting chip.

2. The virtual pixel four-in-one LED lamp bead as claimed in claim 1, characterized in that: The first red light chip and the second red light chip are on the same straight line, and a line L1 connecting the first red light chip and the second red light chip is located between the first green light chip and the second green light chip, and between the first blue light chip and the second blue light chip; The connection line between the first green chip and the second green chip is L2, the connection line between the first blue chip and the second blue chip is L3, and L2 and L3 form an intersection.

3. The virtual pixel four-in-one LED lamp bead as claimed in claim 2, characterized in that: The intersection point formed by L2 and L3 is located on L1.

4. The virtual pixel four-in-one LED lamp bead as claimed in claim 1, characterized in that: The lengths of the first red light chip, the first green light chip, the first blue light chip, and the second red light chip along the first direction are greater than their widths along the second direction; The length of the second green chip and the second blue chip along the first direction is smaller than the width along the second direction.

5. The virtual pixel four-in-one LED lamp bead as claimed in claim 1, characterized in that: The light-emitting chip further includes a third light-emitting chip. The first light-emitting chip, the second light-emitting chip and the third light-emitting chip are cross-matched to form at least four pixel points. The third light-emitting chip is one of a red light chip, a green light chip and a blue light chip.

6. The virtual pixel four-in-one LED lamp bead as claimed in claim 5, characterized in that: The third light-emitting chip is a third red light chip, the first red light chip, the second red light chip and the third red light chip are on the same straight line, and a line L4 connecting the first red light chip, the second red light chip and the third red light chip is located between the first green light chip and the second green light chip, and between the first blue light chip and the second blue light chip; The connection line between the first green chip and the second green chip is L5, the connection line between the first blue chip and the second blue chip is L6, and L5 and L6 form an intersection.

7. The virtual pixel four-in-one LED lamp bead as claimed in claim 6, characterized in that: The intersection point formed by L5 and L6 is located on L4.

8. The virtual pixel four-in-one LED lamp bead according to any one of claims 5 to 7, characterized in that: The lengths of the first red light chip, the second red light chip, and the third red light chip along the first direction are smaller than their widths along the second direction; The lengths of the first green chip, the first blue chip, the second green chip, and the second blue chip along the first direction are greater than their widths along the second direction.

9. A method for preparing a virtual pixel four-in-one LED lamp bead as claimed in any one of claims 1 to 8, characterized in that: include: Fixing the light-emitting chip on the front side of the substrate, arranging the red light chip, the green light chip and the blue light chip to form at least four pixel points; Forming leads on the back side of the substrate and connecting the leads to electrodes of the light emitting chip; The surfaces of the substrate and the light-emitting chip are wrapped to form an encapsulation adhesive layer.

10. A display screen, characterized in that: It comprises a virtual pixel four-in-one LED lamp bead as described in any one of claims 1-8.

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