Semitransparent light layer, LED light emitting device and manufacturing method thereof, display screen

Abstract

This invention relates to a semi-transparent layer, an LED light-emitting device, a method for manufacturing the same, and a display screen. The light-emitting unit of the LED light-emitting device is disposed on the front side of a circuit board and electrically connected to corresponding pads on the front side. The LED light-emitting device also includes a semi-transparent layer that covers at least the area on the front side of the circuit board not covered by the orthographic projection of each light-emitting unit, i.e., the pad area on the front side of the circuit board not covered by each light-emitting unit is also covered. This improves the contrast of the LED light-emitting device and the display screen made using the LED light-emitting device, enhancing the display effect. The semi-transparent layer includes a reflective layer and a black layer attached to the reflective layer. It has a simple structure, low cost, is easy to manufacture with a high yield rate, and provides good one-way visibility.

Description

Technical Field

[0001] This invention relates to the field of light emission, and more particularly to a semi-transparent layer, an LED light emission device and its manufacturing method, and a display screen. Background Technology

[0002] COB (Chip On Board), LED (Light-Emitting Diode), COG (Chip On Glass), and POB (Package-on-Board) are all active-matrix LED display technologies that offer advantages such as high brightness and wide color gamut. Given a maximum brightness limit, reducing the minimum brightness of the LED screen becomes crucial for improving contrast.

[0003] As pixel pitch decreases, the proportion of display area occupied by light-emitting units (which can be LED chips or LED packages) in LED displays is increasing. Coupled with the limitations of PCB (Printed Circuit Board) manufacturing processes, it is difficult to match the size of the pads on the PCB used to solder the light-emitting units to the size of the units themselves. Typically, after the light-emitting units are soldered to the PCB via pads, a portion of the pads is not covered by the light-emitting units. During the soldering process, the solder paste melts and turns silver, covering the surface of the pads. See, for example... Figure 1 The LED display panel shown is a PCB board, where 10 is a black ink layer or black adhesive layer on the PCB board 10 to improve contrast, 102 is a light-emitting unit, and 1011 is a light-emitting unit. After the light-emitting unit 102 is soldered to the pads with solder paste, the solder paste turns silver after melting and covers the silver area of ​​the pads. Silver has reflective properties, which makes the LED display screen not black enough when it is black, that is, it reduces the contrast of the LED display screen and affects the display effect.

[0004] Therefore, improving the contrast ratio of LED displays is a technical problem that urgently needs to be solved. Summary of the Invention

[0005] In view of the shortcomings of the above-mentioned related technologies, the purpose of this invention is to provide a semi-transparent layer, an LED light-emitting device and its manufacturing method, and a display screen, aiming to solve the problem of how to improve the contrast of an LED display screen.

[0006] To solve the above-mentioned technical problems, the present invention provides a semi-transparent layer, the semi-transparent layer comprising a reflective layer and a black layer attached to the reflective layer, the reflective layer comprising reflective particles and gaps between the reflective particles, the gaps forming a first light-transmitting channel for light to pass through the reflective layer.

[0007] The black layer includes a transparent adhesive substrate layer, micron-sized glass microspheres distributed within the transparent adhesive substrate layer, and nano-sized black powder filling the spaces between the micron-sized glass microspheres. Each of the micron-sized glass microspheres constitutes a second light-transmitting channel through which light passes through the black layer.

[0008] The semi-transparent layer in this invention includes a reflective layer and a black layer attached to the reflective layer. The gaps between the reflective particles in the reflective layer form a first light-transmitting channel for light to pass through the reflective layer. The black layer includes a transparent adhesive substrate layer, micron-sized glass microspheres distributed within the transparent adhesive substrate layer, and nano-sized black powder filling the gaps between the micron-sized glass microspheres. Each micron-sized glass microsphere forms a second light-transmitting channel for light to pass through the black layer. Therefore, when there is no light emitted from the reflective layer to the black layer, but only light emitted from the black layer to the reflective layer (e.g., natural light), a portion of the emitted light is reflected by the reflective particles in the reflective layer and emitted through the second light-transmitting channel (this emitted light is called L1), while a portion of the light is reflected by the reflective particles to the black layer. The nano-sized black powder in the color layer is absorbed (this absorbed light is called L3). A portion of the light enters the reflective layer through the first light-transmitting channel and is reflected multiple times by objects below the reflective layer and / or absorbed before returning to the second light-transmitting channel and exiting (this exited light is called L2) or returning to the nano-sized black powder in the black layer and being absorbed. According to the principle of one-way perspective, when the intensity of the L2 light is much less than the intensity of the L1 light, the area covered by the semi-transparent layer appears as black in human vision, thus improving contrast. Conversely, when there is sufficient intensity of light emitted from the reflective layer to the black layer, normal display can be achieved. That is, the one-way perspective visual effect of the semi-transparent layer is used to ensure the display effect while improving contrast.

[0009] Optionally, the ratio of the particle size of the micron-sized glass microspheres to the thickness of the black layer is 0.8 to 1.0.

[0010] Optionally, the thickness of the black layer is 50 micrometers to 100 micrometers.

[0011] Optionally, the micron-sized glass microspheres have a hollow structure.

[0012] Optionally, the volume occupied by the micron-sized glass microspheres in the black layer is 50% to 70% of the volume of the black layer.

[0013] Optionally, the nanoscale black powder includes nanoscale carbon black powder.

[0014] Optionally, the thickness of the reflective layer is 100 nanometers to 300 nanometers.

[0015] Optionally, the reflective particles include at least one of aluminum alloy particles and silver nitrate particles.

[0016] Optionally, the area occupied by the gap in the orthographic projection of the reflective layer is 60% to 70% of the orthographic projection area of ​​the reflective layer.

[0017] Optionally, the side of the black layer away from the reflective layer is a non-smooth surface.

[0018] Based on the same inventive concept, the present invention also provides an LED light-emitting device, comprising:

[0019] A circuit board, wherein a plurality of solder pads are provided on the front side of the circuit board;

[0020] A plurality of light-emitting units are disposed on the front side of the circuit board, and the electrodes of each light-emitting unit are electrically connected to the corresponding pads;

[0021] The semi-transparent layer described above is disposed on the front side of the circuit board, and at least covers the area on the front side of the circuit board that is not covered by the orthographic projection of each of the light-emitting units.

[0022] In this invention, the light-emitting unit of the LED light-emitting device is disposed on the front side of the circuit board and electrically connected to the corresponding pad on the front side; the LED light-emitting device also includes a semi-transparent layer disposed on the front side of the circuit board, which covers at least the area on the front side of the circuit board that is not covered by the orthographic projection of each light-emitting unit, that is, the pad area on the front side of the circuit board that is not covered by each light-emitting unit is also covered, so that the area above the pad is black instead of silver, thereby improving the contrast of the LED light-emitting device and the display screen made using the LED light-emitting device and improving the display effect;

[0023] Furthermore, the semi-transparent layer on the front side of the circuit board allows for the following: when there is no light emitted from the reflective layer to the black layer (i.e., the light-emitting unit is not lit), and only light (e.g., natural light) is emitted from the black layer to the reflective layer, a portion of the emitted light is reflected by reflective particles in the reflective layer and emitted through the second light-transmitting channel (this emitted light is called L1); a portion of the light is reflected by reflective particles and absorbed by nano-sized black powder in the black layer (this absorbed light is called L3); and a portion of the light enters the front side of the circuit board or the surface of the light-emitting unit through the first light-transmitting channel of the reflective layer, and after multiple reflections and / or absorption, returns to the second light-transmitting channel and is emitted (this emitted light is called L2) or returns to the nano-sized black powder in the black layer and is absorbed. Based on the principle of one-way perspective... When the brightness of the external environment (i.e., the outside of the LED light-emitting device) is more than 1.5 times greater than the brightness of the internal environment (i.e., the inside of the LED light-emitting device), the human eye will ignore the received internal ambient light. Since the intensity of the L2 light is much less than the intensity of the L1 light, the brightness of the external light of the LED light-emitting device is much greater than the brightness of the internal light of the LED light-emitting device. At this time, the area covered by the semi-transparent layer appears as black in the human eye, thus improving the contrast. Conversely, when there is light emitted from the self-reflecting layer to the black layer (i.e., the light-emitting unit is not lit), the brightness of the internal light of the LED light-emitting device is much greater than 1.5 times the brightness of the external light of the LED light-emitting device, thus achieving normal display. In other words, the one-way perspective visual effect of the semi-transparent layer is used to ensure the display effect while improving the contrast.

[0024] The LED light-emitting device also includes a first encapsulation layer disposed between the front side of the circuit board and the semi-transparent layer.

[0025] Optionally, the semi-transparent layer completely covers the first encapsulation layer, or the first encapsulation layer in the area directly above each of the light-emitting units is exposed to the semi-transparent layer, while other areas are covered by the semi-transparent layer.

[0026] Optionally, the semi-transparent layer is attached to the front side of the circuit board, and the LED light-emitting device further includes a second encapsulation layer disposed on the semi-transparent layer and covering each of the light-emitting units.

[0027] Optionally, the semi-transparent layer may also cover at least one of the side surface and the top light-emitting surface of each of the light-emitting units; the side of the light-emitting unit away from the front of the circuit board is the top light-emitting surface, the side close to the front of the circuit board is the bottom surface, and the surface between the top light-emitting surface and the bottom surface is the side surface.

[0028] Based on the same inventive concept, the present invention also provides a method for manufacturing the semi-transparent layer as described above, comprising:

[0029] The reflective layer is formed on the bearing surface of the substrate by vacuum ion plating or vapor deposition.

[0030] The micron-sized glass microspheres and the nano-sized black powder are uniformly mixed in a transparent adhesive to obtain a mixed adhesive. The micron-sized glass microspheres and the nano-sized black powder carry the same polarity of charge, so they repel each other in the transparent adhesive.

[0031] A mixed adhesive layer is disposed on the reflective layer, and the mixed adhesive layer is cured to obtain the black layer.

[0032] The method for manufacturing a semi-transparent layer provided by this invention can produce a semi-transparent layer through a mature and simple manufacturing process, with high manufacturing efficiency, high yield, and low cost.

[0033] Based on the same inventive concept, the present invention also provides a method for manufacturing an LED light-emitting device as described above, characterized in that it includes:

[0034] A plurality of light-emitting units are disposed on the front side of the circuit board, and the electrodes of each light-emitting unit are electrically connected to the corresponding pads.

[0035] A semi-transparent layer is disposed on the front side of the circuit board, and the semi-transparent layer covers at least the area on the front side of the circuit board that is not covered by the orthographic projection of each of the light-emitting units.

[0036] The LED light-emitting device obtained by the present invention has a semi-transparent layer covering the pad area on the front side of the circuit board that is not covered by each light-emitting unit. This makes the area above the pad black instead of silver, thus improving the contrast of the LED light-emitting device. Furthermore, the one-way perspective effect of the semi-transparent layer can be used to improve the display effect while ensuring the display contrast of the LED light-emitting device.

[0037] Optionally, the provision of the semi-transparent layer on the front side of the circuit substrate includes:

[0038] The reflective layer is formed on the front side of the circuit board by vacuum ion plating or vapor deposition.

[0039] The micron-sized glass microspheres and the nano-sized black powder are uniformly mixed in a transparent adhesive to obtain a mixed adhesive. The micron-sized glass microspheres and the nano-sized black powder carry the same polarity of charge, so they repel each other in the transparent adhesive.

[0040] A mixed adhesive layer is disposed on the reflective layer, and the mixed adhesive layer is cured to obtain the black layer.

[0041] Optionally, the provision of the semi-transparent layer on the front side of the circuit substrate includes:

[0042] A bonding adhesive layer is applied to the carrier membrane;

[0043] The reflective layer is formed on the adhesive layer by vacuum ion plating or vapor deposition.

[0044] The micron-sized glass microspheres and the nano-sized black powder are uniformly mixed in a transparent adhesive to obtain a mixed adhesive. The micron-sized glass microspheres and the nano-sized black powder carry the same polarity of charge, so they repel each other in the transparent adhesive.

[0045] A mixed adhesive layer is disposed on the reflective layer, and the mixed adhesive layer is cured to obtain the black layer;

[0046] Remove the carrier film, cover the front side of the bonding adhesive layer onto the circuit board and hot press it.

[0047] Based on the same inventive concept, the present invention also provides a display screen, including a driving element and an LED light-emitting device as described above, wherein the driving element is disposed on the front or back of the circuit board and is electrically connected to each of the light-emitting units.

[0048] The display screen provided by the present invention has a semi-transparent layer covering the pad area on the front side of the circuit board of the LED light-emitting device that is not covered by each light-emitting unit, so that the area above the pad is black instead of silver, which can improve the contrast of the display screen. Moreover, the one-way perspective effect of the semi-transparent layer can be used to improve the display effect while ensuring the display contrast. Attached Figure Description

[0049] Figure 1 This is a schematic diagram of a display panel in related technologies;

[0050] Figure 2 This is a schematic diagram of a circuit board structure with a light-emitting unit provided in an embodiment of the present invention;

[0051] Figure 3 This is a schematic diagram of the principle structure of the semi-transparent layer provided in an embodiment of the present invention;

[0052] Figure 4 This is a schematic diagram of the structure of the reflective layer provided in an embodiment of the present invention;

[0053] Figure 5 This is a schematic diagram of the structure of the black layer provided in an embodiment of the present invention;

[0054] Figure 6 This is an enlarged schematic diagram of the black layer provided in an embodiment of the present invention;

[0055] Figure 7-1 Schematic diagram of the optical path of the semi-transparent layer provided in the embodiments of the present invention Figure 1 ;

[0056] Figure 7-2 Schematic diagram of the optical path of the semi-transparent layer provided in the embodiments of the present invention Figure 2 ;

[0057] Figure 8 A schematic diagram of the structure of the LED light-emitting device provided in the embodiments of the present invention. Figure 1 ;

[0058] Figure 9-1 for Figure 8 Schematic diagram of the light path of the LED light-emitting device Figure 1 ;

[0059] Figure 9-2 for Figure 8 Schematic diagram of the light path of the LED light-emitting device Figure 2 ;

[0060] Figure 9-3 A schematic diagram of a planar mirror image provided in an embodiment of the present invention;

[0061] Figure 9-4 A schematic diagram of specular reflection provided in an embodiment of the present invention;

[0062] Figure 9-5 A schematic diagram of diffuse reflection provided in an embodiment of the present invention;

[0063] Figure 10 A schematic diagram of the structure of the LED light-emitting device provided in the embodiments of the present invention. Figure 2 ;

[0064] Figure 11 A schematic diagram of the structure of the LED light-emitting device provided in the embodiments of the present invention. Figure 3 ;

[0065] Figure 12 A schematic diagram of the structure of the LED light-emitting device provided in the embodiments of the present invention. Figure 4 ;

[0066] Figure 13 A schematic diagram of the structure of the LED light-emitting device provided in the embodiments of the present invention. Figure 5 ;

[0067] Figure 14 A schematic diagram of the structure of the LED light-emitting device provided in the embodiments of the present invention. Figure 6 ;

[0068] Figure 15 Schematic diagram seven of the structure of the LED light-emitting device provided in the embodiments of the present invention;

[0069] Figure 16 A schematic diagram of the structure of the LED light-emitting device provided in the embodiments of the present invention. Figure 8 ;

[0070] Figure 17 Schematic diagram nine of the structure of the LED light-emitting device provided in the embodiments of the present invention;

[0071] Figure 18 A schematic diagram of the process for fabricating a semi-transparent layer provided in an embodiment of the present invention. Figure 1 ;

[0072] Figure 19 This is a schematic diagram of the manufacturing process of an LED light-emitting device provided in an embodiment of the present invention;

[0073] Figure 20-1 A schematic diagram of the manufacturing process of the LED light-emitting device provided in the embodiments of the present invention. Figure 1 ;

[0074] Figure 20-2 A schematic diagram of the manufacturing process of the LED light-emitting device provided in the embodiments of the present invention. Figure 2 ;

[0075] Figure 20-3 A schematic diagram of the manufacturing process of the LED light-emitting device provided in the embodiments of the present invention. Figure 3 ;

[0076] Figure 21 A schematic diagram of the process for fabricating a semi-transparent layer provided in an embodiment of the present invention. Figure 2 ;

[0077] Figure 22-1 A schematic diagram of the manufacturing process of the LED light-emitting device provided in the embodiments of the present invention. Figure 4 ;

[0078] Figure 22-2 A schematic diagram of the manufacturing process of the LED light-emitting device provided in the embodiments of the present invention. Figure 5 ;

[0079] Figure 22-3 A schematic diagram of the manufacturing process of the LED light-emitting device provided in the embodiments of the present invention. Figure 6 ;

[0080] Figure 23 This is a schematic diagram of the structure of a display screen provided in an embodiment of the present invention. Detailed Implementation

[0081] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0082] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0083] This embodiment provides a semi-transparent layer (also known as a one-way transparent layer), which can be used in LED light-emitting devices to improve the display contrast and display effect of the LED light-emitting devices. Please refer to... Figure 3 As shown in the figure (this figure is a schematic diagram of the structure of the semi-transparent layer 3 in terms of optical path principle, not a schematic diagram of the actual layer structure of the semi-transparent layer 3), the semi-transparent layer 3 includes a reflective layer 31 and a black layer 32 attached to the reflective layer 31, wherein:

[0084] The reflective layer 31 includes reflective particles 311 and gaps between the reflective particles 311, which form a first light-transmitting channel 312 for light to pass through the reflective layer 31. A schematic diagram of an example structure of the reflective layer 31 is shown below. Figure 4As shown, it includes reflective particles 311 laid flat on the bearing surface of the carrier (i.e., the adhesion surface of the reflective layer 31), and gaps between each reflective particle 311, with each gap forming a first light-transmitting channel 312. The reflective particles 311 in this embodiment can be in molecular form or other particle forms. The reflective particles 311 in this embodiment can be set on the bearing surface using, but is not limited to, mature vacuum ion plating or evaporation processes, which are simple to manufacture, low in cost, and highly controllable. The reflective particles 311 in this embodiment can include at least one of various metallic optical particles (e.g., including but not limited to nano-sized aluminum alloy particles, silver nitrate particles, Ag particles, Al particles, Rh particles, Cr particles, Pt particles, Cu particles, Au particles, Ti particles, preferably including at least one of low-cost, high-reflection-effect, and versatile aluminum alloy particles and silver nitrate particles) and non-metallic optical particles (e.g., including but not limited to nano-sized TiO2 particles, ZnO particles, BaSO4 particles, Al2O3 particles). In this embodiment, the reflective particles 311 can be nanometer-sized particles, and the particle size of the reflective particles 311 determines the thickness of the reflective layer 31. For example, in some applications, the reflective particles 311 can be, but are not limited to, particles with a particle size of 2 nanometers to 300 nanometers, and the corresponding thickness of the formed reflective layer 31 is 2 nanometers to 300 nanometers. Setting the thickness of the reflective layer 31 to the nanometer level can improve contrast while making it easier to reduce the thickness of the LED light-emitting device, thus facilitating the ultra-thin design of the LED light-emitting device. In some application scenarios, the reflective particles 311 can specifically be particles with a particle size of 100 nanometers to 300 nanometers, and the corresponding thickness of the formed reflective layer 31 is 100 nanometers to 300 nanometers. For example, the particle sizes of the reflective particles 311 can be 100 nanometers, 150 nanometers, 200 nanometers, 250 nanometers, 300 nanometers, etc. It should be understood that, correspondingly, the width and height of each first light-transmitting channel 312 (i.e., gap) in this embodiment are also nanometer-sized.

[0085] In this embodiment, see Figure 3 and Figure 4As shown, the first light-transmitting channels 312 of the reflective layer 31 form a matrix-like distribution. Furthermore, in order to improve contrast while ensuring good light extraction efficiency to meet display requirements, in this embodiment, the area occupied by the gaps in the reflective layer 31 (i.e., the first light-transmitting channels 312) in the orthographic projection of the reflective layer 31 is set to 60% to 70% of the orthographic projection area of ​​the reflective layer 31. For example, in some examples, this area percentage can be specifically set to 60%, 65%, or 70%, etc. Correspondingly, the area occupied by the reflective particles 311 in the orthographic projection of the reflective layer 31 is 30% to 40% of the orthographic projection area of ​​the reflective layer 31. This setting can greatly reduce the proportion of reflective particles 311, reduce the use of reflective particles 311, and thus help reduce costs.

[0086] The black layer 32 includes a transparent adhesive substrate layer (which serves as a carrier layer for supporting micron-sized glass microspheres and nano-sized black powder). Figure 3 (Not shown in the image) Micron-sized glass microspheres 321 are distributed within the transparent adhesive substrate layer, and nano-sized black powder is filled between each micron-sized glass microsphere 321. The nano-sized black powder is deposited on each micron-sized glass microsphere 321 to form black light-blocking units 322. Each micron-sized glass microsphere 321 constitutes a second light-transmitting channel for light to pass through the black layer 32. In this example, at least a portion of the second light-transmitting channels can be positioned to correspond to at least a portion of the first light-transmitting channels 312, thereby allowing light to pass through the semi-transparent layer 3 through the corresponding first light-transmitting channels 312 and second light-transmitting channels. See the schematic diagram of an example structure of the black layer 32. Figure 5 As shown, it includes a transparent adhesive substrate layer 320, micron-sized glass microspheres 321 distributed within the transparent adhesive substrate layer 320, and nano-sized black powder distributed within the transparent adhesive substrate layer 320 and filling the spaces between the micron-sized glass microspheres 321. The nano-sized black powder is deposited together within the transparent adhesive substrate layer to form black light-blocking units 322. In this embodiment, to prevent the nano-sized black powder from adhering to the micron-sized glass microspheres 321 and affecting their light transmittance, the micron-sized glass microspheres 321 can be charged with an electric charge during the fabrication of the black layer 32 to make them negatively charged (see [link to documentation]). Figure 6 As shown in A, Figure 6 for Figure 5 (Partial enlarged schematic diagram of the black layer 32), and the nano-sized black powder is also set to have a negative charge (see...). Figure 6As shown in A), the micron-sized glass microspheres 321 and the nano-sized black powder mixed in the transparent adhesive substrate layer 320 repel each other, which means that the micron-sized glass microspheres 321 can displace the negatively charged nano-sized black powder, thereby preventing the nano-sized black powder from adhering to the micron-sized glass microspheres 321, and allowing the second light-transmitting channel formed by the micron-sized glass microspheres 321 to be widened on the top and / or bottom surface of the black layer 32.

[0087] In this embodiment, to ensure that the black layer 32 achieves both improved contrast and a specific light extraction efficiency, the volume occupied by the micron-sized glass microspheres 321 in the black layer 32 can be set to 50% to 70% of the volume of the black layer. Specifically, this volume percentage can be set to 50%, 55%, 60%, 65%, or 70%, etc. In other words, it can also be understood that the area occupied by the micron-sized glass microspheres 321 in the orthographic projection of the black layer 32 can be set to 50% to 70% of the orthographic projection area of ​​the black layer.

[0088] In this embodiment, the thickness of the black layer 32 can be set to 50 micrometers to 100 micrometers. Setting the thickness of the black layer 32 to the micrometer level can improve contrast while also facilitating the reduction of the thickness of the semi-transparent layer, which is beneficial for the ultra-thin design of the LED light-emitting device. Furthermore, to ensure that the micrometer-sized glass microspheres 321 can reliably form a second light-transmitting channel for light to pass through the black layer 32, the ratio of the particle size of the micrometer-sized glass microspheres 321 to the thickness of the black layer 32 can be set to 0.8 to 1.0, that is, the particle size of the micrometer-sized glass microspheres 321 can be, but is not limited to, 40 micrometers to 100 micrometers. For example, in some application scenarios, when the ratio of the particle size of the micrometer-sized glass microspheres 321 to the thickness of the black layer 32 is set to 0.8, and the thickness of the black layer 32 is 50 micrometers, then... Micron-sized glass microspheres 321 with a particle size of approximately 40 micrometers are used. When the ratio of the particle size of the micron-sized glass microspheres 321 to the thickness of the black layer 32 is set to 0.9, and the thickness of the black layer 32 is 100 micrometers, then micron-sized glass microspheres 321 with a particle size of approximately 90 micrometers are used. When the ratio of the particle size of the micron-sized glass microspheres 321 to the thickness of the black layer 32 is set to 1.0, and the thickness of the black layer 32 is 100 micrometers, then micron-sized glass microspheres 321 with a particle size of approximately 100 micrometers are used. Glass microspheres are a new type of material with wide applications and special properties that has been developed in recent years. This product can be made from borosilicate raw materials through high-tech processing. It has advantages such as light weight, low thermal conductivity, sound insulation, high dispersion, good electrical insulation, good thermal stability, high strength, good chemical stability, and low cost. Furthermore, since the micron-sized glass microspheres 321 have low thermal conductivity and good thermal stability, they can also reduce the heat generated by the electronic components on the front side of the circuit board 1 during operation and conduct it out of the black layer 32, and ensure the stability of the black layer 32.

[0089] It should be understood that the micron-sized glass microspheres 321 in this embodiment can be solid glass microspheres. However, in some application scenarios, hollow micron-sized glass microspheres 321 are preferred. Using hollow micron-sized glass microspheres 321 can further improve the heat insulation performance of the black layer 32 and make the black layer 32 lighter. When using hollow micron-sized glass microspheres 321, the wall thickness of the micron-sized glass microspheres 321 can be, but is not limited to, 1 micrometer to 2 micrometers. The nano-sized black powder in this embodiment can include, but is not limited to, nano-sized carbon black powder, and can be, but is not limited to, nano-sized carbon black powder with a particle size of 1 nanometer to 100 nanometers, thereby ensuring the blackness of the black layer 32. The transparent adhesive substrate layer 320 in this embodiment can be, but is not limited to, transparent adhesive. The transparent adhesive can be, but is not limited to, PET (polyester), PVC (polyvinyl chloride), modified epoxy, modified silicone, etc., and has the advantages of low cost and good versatility.

[0090] In this embodiment, the side of the black layer 32 away from the reflective layer 31 (i.e., the top surface of the black layer 32) can also be processed according to visual effect requirements. For example, in some application scenarios, when it is necessary for the black layer 32 to present a black mirror effect, the top surface of the black layer 32 can be set as a smooth surface; when it is necessary to avoid the black layer 32 from presenting a black mirror effect, the top surface of the black layer 32 can be set as a non-smooth surface. The non-smooth surface can include, but is not limited to, a matte surface, a frosted surface, a matte surface, or a rough surface with different degrees of texture. Setting the top surface of the black layer 32 as a non-smooth surface allows light from the external environment to be diffusely reflected on the top surface of the black layer 32, which can reduce the sharpness of the LED, reduce ambient light interference, reduce the mirror effect on the surface of the LED light-emitting device, thereby eliminating the interference of ambient light when the LED light-emitting device is lit. While ensuring high black contrast, it achieves a better viewing effect and can be better applied to various application scenarios.

[0091] Based on the semi-transparent layer with the specific structure described in this embodiment, when there is no light emitted from the self-reflecting layer to the black layer, but only light emitted from the black layer to the reflecting layer, a portion of the emitted light L1 is reflected by the reflective particles in the reflecting layer and emitted through the second light transmission channel, a portion of the light L3 is reflected by the reflective particles to the nano-sized black powder in the black layer and absorbed, and a portion of the light L2 is emitted through the first light transmission channel of the reflecting layer and enters below the reflecting layer. After being reflected multiple times by objects below the reflecting layer (such as circuit boards, light-emitting units, etc.) and / or absorbed, it returns to the second light transmission channel and is emitted or returned to the nano-sized black powder in the black layer and absorbed. When the intensity of the L2 light is much less than the intensity of the L1 light, the area covered by the semi-transparent layer appears as black in human vision, thus improving the contrast. Conversely, when there is sufficient intensity of light emitted from the self-reflecting layer to the black layer, normal display can be achieved. That is, the one-way perspective visual effect of the semi-transparent layer is used to ensure the display effect while improving the contrast.

[0092] To facilitate understanding, the following example illustrates the application of a semi-transparent layer in an LED light-emitting device, which includes:

[0093] A circuit board has several pads on its front side for electrical connection with the electrodes of the light-emitting units; several light-emitting units are provided on the front side of the circuit board, and the electrodes of each light-emitting unit are electrically connected to the corresponding pads.

[0094] It should be understood that the distribution of each pad on the front side of the circuit board in this embodiment can be flexibly configured, for example, it can be... Figure 1 The matrix distribution shown can also be configured in other ways as needed, and this embodiment does not limit it. In some examples of this embodiment, the material of the pads can be, but is not limited to, copper, silver, gold, etc. In this embodiment, when the pads on the front side of the circuit board are electrically connected to the electrodes of the light-emitting unit, the electrical connection can be made by, but is not limited to, solder (e.g., solder paste) or conductive adhesive. The light-emitting unit in this embodiment can be an LED chip or an LED package device (e.g., an LED package device with a light conversion layer or a light-transmitting adhesive layer directly on the surface of the LED chip). In terms of size classification, the LED chip used in this embodiment can include a Mini light-emitting unit, that is, the LED chip used in this embodiment is a micro LED chip; in terms of the distribution of the LED chip electrodes, it can include at least one of flip-chip LED chips, upright LED chips, and vertical LED chips.

[0095] In this embodiment, the side opposite to the front of the circuit board is the back of the circuit board; it should be understood that the front and back of the circuit board in this embodiment are relative. It should also be understood that the circuit board in this embodiment can be made of a rigid material, such as, but not limited to, phenolic paper laminate, epoxy paper laminate, polyester glass mat laminate, epoxy glass cloth laminate, BT resin board, or glass board; the circuit board in this embodiment can also be made of a flexible material, such as, but not limited to, polyester film, polyimide film, or fluorinated ethylene propylene film. In some examples, corresponding circuits can be integrated into or on the surface of the circuit board according to application requirements, such as, but not limited to, display circuits and driving circuits connected to the light-emitting unit.

[0096] In some application scenarios of this embodiment, the LED light-emitting device can be a display module for display, and its circuit board is a display board with corresponding display circuits. Several light-emitting units disposed on the circuit board can constitute multiple pixel units. In this application scenario, a pixel unit can include at least two light-emitting units, and the number and type of light-emitting units included in each pixel unit (including the size of the light-emitting units, the emission color, whether they are upright, inverted, or vertical, etc.) can be the same, different, or partially the same and partially different, and can be flexibly set according to the specific application scenario. For example, in some examples, a pixel unit can include three light-emitting units that emit red, blue, and green light respectively, namely, a red light-emitting unit, a green light-emitting unit, and a blue light-emitting unit arranged sequentially. In other examples, in addition to red, green, and blue light-emitting units, a white light-emitting unit can also be included in the pixel unit. It should be understood that the specific arrangement of the light-emitting units within the pixel unit in this embodiment can be a triangular arrangement, a linear arrangement, a centrally symmetrical arrangement, etc., and this embodiment does not limit it.

[0097] The LED light-emitting device in this embodiment further includes a semi-transparent layer disposed on the front side of the circuit board, and this semi-transparent layer is the same as the semi-transparent layer in the above examples, which at least covers the area on the front side of the circuit board that is not covered by the orthographic projection of each light-emitting unit; it should be noted that:

[0098] In this embodiment, the semi-transparent layer is disposed on the front side of the circuit board. It can be that the semi-transparent layer is directly attached to the front side of the circuit board, or it can be disposed indirectly above the front side of the circuit board (that is, there are other layer structures between the semi-transparent layer and the front side of the circuit board).

[0099] In this embodiment, the semi-transparent layer covers at least the area on the front side of the circuit board that is not covered by the orthographic projection of each light-emitting unit. This means that on the front side of the circuit board, apart from the area covered by the orthographic projection of each light-emitting unit on that front side, the other areas are covered by the semi-transparent layer. For example, see [example description]. Figure 2 As shown, Figure 2 The diagram shows a circuit board 1 for an LED light-emitting device, and several light-emitting units 2 disposed on the front side of the circuit board 1. The area on the front side of the circuit board 1 not covered by the orthographic projection of each light-emitting unit 2 includes... Figure 2 The regions shown in S clearly include... Figure 1 The area shown in 1011. Therefore, the contrast of the LED light-emitting device can be improved, thus enhancing its display effect.

[0100] The semi-transparent layer used in this embodiment has a one-way perspective effect. That is, when the ambient light intensity outside the LED light-emitting device is greater than or equal to 1.5 times the ambient light intensity inside the LED light-emitting device, the area covered by the semi-transparent layer inside the LED light-emitting device appears black to the human eye, thus improving contrast. Conversely, when the brightness of the internal light of the LED light-emitting device is greater than 1.5 times the brightness of the external light, the LED light-emitting device can achieve normal display. See, for example... Figure 7-1 As shown, when the light-emitting unit is not lit, that is, when the LED light-emitting device is off, no light is generated in the internal environment, and the light that the human eye can see theoretically exists mainly in the following three parts:

[0101] The ambient light is reflected by the reflective particles in the reflective layer 31 as light L1;

[0102] A small portion of the external ambient light enters the internal environment through the corresponding first and second light transmission channels, and after being reflected and absorbed multiple times in the internal environment, it returns to the external environment as light L2.

[0103] Ambient light absorbed by the black light-blocking unit 322 in the black layer appears as black (L3) due to the absorption of light.

[0104] According to the principle of one-way perspective, when the brightness of the external ambient light is more than 1.5 times greater than the brightness of the internal ambient light, the human eye will ignore the received internal ambient light. Figure 7-1 The intensity of light at L2 is much less than that at L1; at this time, the area covered by the semi-transparent layer 3 appears as black to the human eye.

[0105] See Figure 7-2 As shown, when the light-emitting unit is lit, that is, when the LED light-emitting device is displayed, the light-emitting unit in the internal environment produces light. The light that the human eye can see theoretically consists of the following five main parts:

[0106] The ambient light is reflected by the reflective particles in the reflective layer 31 as light L1;

[0107] A small portion of the external ambient light enters the internal environment through the corresponding first and second light transmission channels, and after being reflected and absorbed multiple times in the internal environment, it returns to the external environment as light L2.

[0108] Ambient light absorbed by the black light-blocking unit 322 in the black layer appears as black (L3) due to the absorption of light.

[0109] Light L4, generated by the light-emitting unit, is directly incident into the external environment through the corresponding first and second light-transmitting channels;

[0110] Light L5, generated by LEDs, is reflected and absorbed multiple times in the internal environment and then enters the external environment through the corresponding first and second light transmission channels.

[0111] A typical display screen with a brightness of 300-500 nits can achieve a very good display effect, while the light emitted by LEDs, namely L4+L5, can reach a brightness of 800-2000 nits, which is greater than 300-500 nits; at this level, the content displayed on the LED display screen can be seen completely by human vision.

[0112] As described above, in this embodiment, the semi-transparent layer 3 can be indirectly disposed on the front side of the circuit board 1, or it can be directly attached to the front side of the circuit board 1. For ease of understanding, this embodiment will be described below with reference to several example structures shown in the accompanying drawings.

[0113] In one example where the semi-transparent layer 3 is indirectly disposed on the front side of the circuit board 1, the LED light-emitting device may further include a first encapsulation layer disposed between the front side of the circuit board and the semi-transparent layer. In this embodiment, the first encapsulation layer is a light-transmitting layer. It should be understood that the formation process and material of the first encapsulation layer in this embodiment can be flexibly set and are not limited thereto. For example, in some examples, the first encapsulation layer may be, but is not limited to, an adhesive layer, and its formation method may include, but is not limited to, coating, molding, printing, pre-forming a film, and then mounting. In this embodiment, the first encapsulation layer can provide waterproofing, moisture resistance, and impact protection, protecting the light-emitting unit and serving as a substrate for the semi-transparent layer. For example, in some application examples, the first encapsulation layer may be a transparent encapsulation layer using transparent epoxy adhesive, thereby providing a sealed protection for the light-emitting unit on the circuit board 1. In some application scenarios, at least one of white powder (including but not limited to SiO2 powder), melanin, and light-diffusing particles may be added to the transparent epoxy adhesive as needed to further adjust the light emission effect of the LED light-emitting device. Furthermore, in this embodiment, the upper surface of the first encapsulation layer (that is, the front side of the first encapsulation layer away from the circuit board) can be set as a matte surface, glossy surface, frosted surface, or matte surface as needed, thereby achieving different appearance effects and light emission effects, thus further enriching the display effect and improving user experience satisfaction.

[0114] See an example structure in which the semi-transparent layer 3 is indirectly disposed on the front side of the circuit board 1. Figure 8 As shown, it includes a circuit board 1, a plurality of light-emitting units 2 disposed on the front surface of the circuit board 1, and a first encapsulation layer 41 disposed on the front surface of the circuit board 1 and covering all the light-emitting units 2. In this embodiment, the side of the light-emitting unit 2 away from the front surface of the circuit board 1 is the top light-emitting surface, the side close to the front surface of the circuit board 1 is the bottom surface, and the surface between the top light-emitting surface and the bottom surface is the side surface. The LED light-emitting device also includes a semi-transparent layer 3 formed on the first encapsulation layer 41. In this example, the semi-transparent layer 3 covers the areas of the front surface of the circuit board 1 that are not covered by the orthographic projection of each light-emitting unit 2, and also covers the top light-emitting surface of each light-emitting unit 2, that is, in this example, the semi-transparent layer 3 completely covers the first encapsulation layer. For a schematic model of the light path of the LED light-emitting device in this example when its light-emitting units 2 are not lit, that is, when the screen is off, please refer to [reference needed]. Figure 9-1 As shown, see the schematic model of the light path when lit. Figure 9-2 As shown. To facilitate understanding, this embodiment will be illustrated below using the scenario of an LED light-emitting device applied to a display screen, combined with some concepts from the existing display field.

[0115] Current LCD screens refer to commonly used LCD screens, with a typical brightness of 350 nits and a maximum of 500 nits. Although the brightness of current LCD screens is relatively low, they incorporate color filters with a Black Matrix, allowing them to display deep blacks when the screen is off. In fact, the contrast ratio of current LCD screens is among the best of all types of displays. That is, although the brightness is low, as long as the ratio of the off-screen black brightness to the maximum brightness when the screen is on is high enough, an extremely high black contrast ratio can still be achieved.

[0116] COB Display: As mentioned in the background, ordinary COB displays have exposed solder pads. When the screen is off, the human eye sees only natural light reflected from the silver solder paste on the surface of the pads. However, the surface of the solder paste is uneven and cannot form a mirror, so the human eye sees only a silver color. Based on the above analysis, the semi-transparent layer 3 in this embodiment blocks all the silver light. Furthermore, when the screen is off, due to the one-way perspective principle, the human eye can only see the semi-transparent layer 3, thus achieving the purpose of blocking the silver solder pads. The semi-transparent layer 3 is also highly black, thereby improving black contrast.

[0117] Regarding the understanding of "a brightness of 300-500 nits for a typical display screen can achieve a very good display effect": A brightness of 300-500 nits for a typical display screen can achieve a very good display effect. This means that in a natural environment, as long as the brightness of the display screen reaches at least 300 nits, natural light is not enough to interfere with the human eye's viewing of the display screen's image. In other words, the human eye can obtain a complete display effect. Therefore, as long as the brightness of the display screen reaches at least 300 nits, it can achieve a display.

[0118] for Figure 7-1 and Figure 9-1 Explanation of the light received by the human eye: When the light-emitting unit is not lit (i.e., the screen is off), the light received by the human eye is L1+L2. L3 is the light absorbed by black, which appears as black in human vision, so it is represented by a dashed line.

[0119] If we denote external natural light as Lout, then L1, L2, and L3 represent three parts of external natural light. One part is directly reflected by the reflective layer and received by the human eye (L1); another part enters the internal environment, undergoes multiple reflections and absorptions before returning to the external environment and being received by the human eye (L2); and the third part is directly absorbed by darkness (L3). Therefore, Lout... 外 The value is greater than 1.5*(L1+L2+L3), therefore the area covered by the semi-transparent layer 3 appears as black to the human eye. When the top surface of the black layer 32 is smooth, the semi-transparent layer 3 can be visually regarded as a black mirror.

[0120] for Figure 7-2and Figure 9-2 Explanation of the light received by the human eye: When the light-emitting unit is lit, the LED light emission is received by the human eye in two parts, namely L4 + L5. Referring to the above description of the proportions of the first and second light transmission channels, it can be seen that the minimum value of L4 + L5 can reach more than 50% of the LED's luminous intensity. If the LED luminous intensity is expressed as L... 内 Then L 内 >L4+L5>50%L 内 , while 50% L 内 The display can reach 400 nits to 1000 nits, so L4+L5>300 nits, at which point the user can obtain the full display effect.

[0121] Regarding the explanation that when the top surface of the black layer 32 is smooth, the semi-transparent layer 3 can be visually regarded as a black mirror: First, for the principle of a mirror, please refer to... Figure 9-3 As shown: The light emitted by candle B1 is reflected by the smooth reflective layer in mirror C. The human eye receives the reflected light, and the image presented in the human brain is candle B2, creating the illusion that candle B1 is in the mirror. This is the principle of mirror reflection.

[0122] And see Figure 7-1 and Figure 9-2 The micron-sized glass microspheres in the black layer 32 are glass crystals, and the reflective layer 31 contains reflective particles. When the light-emitting unit does not emit light, the micron-sized glass microspheres and reflective particles form a mirror. However, due to the presence of the black light-blocking unit 322 in the black layer 32, it can be imagined that a mirror has a Black Matrix composed of black light-blocking units 322 added to it. Since the micron-sized glass microspheres are micron-sized crystals, they appear as a black mirror to the human eye.

[0123] In this embodiment, the top surface of the black layer 32 is set as a non-smooth surface to form diffuse reflection on that top surface. For example... Figure 9-4 As shown, when the top surface of the black layer 32 is a smooth surface, a layer will form on that top surface. Figure 9-4 The specular reflection shown. The top surface of black layer 32 is a non-smooth surface, as shown... Figure 9-5 When a rough surface is formed as shown, it will form on the top surface. Figure 9-5 The diffuse reflection shown in the image means that what the human eye sees is not a complete mirror image (it can be understood as a matte screen). Because diffuse reflection makes the mirror image incomplete, it can reduce ambient light interference and improve the display effect.

[0124] Another example structure in which the semi-transparent layer 3 is indirectly disposed on the front side of the circuit board 1 is shown in [reference]. Figure 10 As shown, it is similar to Figure 8Compared with the LED light-emitting device shown, the main difference is that the thickness of the first encapsulation layer 41 is basically equal to the height of each light-emitting unit 2, the top light-emitting surface of each light-emitting unit 2 (that is, the side of the light-emitting unit 2 away from the circuit board 1) is exposed on the first encapsulation layer 41, and the semi-transparent layer 3 located above the top light-emitting surface of each light-emitting unit 2 is directly attached to the top light-emitting surface of each light-emitting unit 2; and the semi-transparent layer 3 completely covers the top surface of the first encapsulation layer 41.

[0125] See another example structure in which the semi-transparent layer 3 is indirectly disposed on the front side of the circuit board 1. Figure 11 As shown, it is similar to Figure 8 Compared to the LED light-emitting device shown, the main difference is that the first encapsulation layer 41 is thinner, and its top surface is unevenly distributed along with the layout of the light-emitting unit 2.

[0126] See another example structure in which the semi-transparent layer 3 is indirectly disposed on the front side of the circuit board 1. Figure 12 As shown, it is similar to Figure 8 Compared to the LED light-emitting device shown, the main difference is that the semi-transparent layer 3 covers the areas on the front of the circuit board 1 that are not covered by the orthographic projection of each light-emitting unit 2, while the top light-emitting surface of each light-emitting unit 2 is exposed to the semi-transparent layer 3, meaning that the semi-transparent layer 3 does not cover the top light-emitting surface of each light-emitting unit 2. In this example, since the semi-transparent layer 3 does not cover the top light-emitting surface of each light-emitting unit 2, most of the light emitted from the top light-emitting surface of each light-emitting unit 2 can be emitted directly through the first encapsulation layer 41 without passing through the semi-transparent layer 3, thus improving the display brightness.

[0127] See an example structure in which the semi-transparent layer 3 is directly attached to the front side of the circuit board 1. Figure 13 As shown, it includes a circuit board 1, a plurality of light-emitting units 2 disposed on the front side of the circuit board 1, and a semi-transparent layer 3 attached to the front side of the circuit board 1. The semi-transparent layer 3 covers the areas of the front side of the circuit board 1 that are not covered by the orthographic projection of each light-emitting unit 2. The top light-emitting surface and side surface of each light-emitting unit 2 are exposed to the semi-transparent layer 3. Therefore, most of the light emitted from the top light-emitting surface and side surface of each light-emitting unit 2 can be emitted without passing through the semi-transparent layer 3, thereby improving its light emission efficiency and ensuring display brightness. The LED light-emitting device in this example also includes a second encapsulation layer 42 disposed on the semi-transparent layer 3 and covering each light-emitting unit 2. The material, shape, and formation method of the second encapsulation layer 42 in this example may be the same as, but not limited to, the first encapsulation layer 41 in the above examples, and will not be described in detail here.

[0128] Another example structure in which the semi-transparent layer 3 is directly attached to the front side of the circuit board 1 is shown in [reference]. Figure 14 As shown, it is similar to Figure 13Compared to the LED light-emitting device shown, the main difference is that the semi-transparent layer 3 also covers the sides of each light-emitting unit 2, and the top light-emitting surface of each light-emitting unit 2 is exposed to the semi-transparent layer 3. Therefore, most of the light from the top light-emitting surface of each light-emitting unit 2 can be emitted without passing through the semi-transparent layer 3, thereby improving its light emission efficiency and ensuring display brightness.

[0129] Another example structure in which the semi-transparent layer 3 is directly attached to the front side of the circuit board 1 is shown in [reference]. Figure 15 As shown, it is similar to Figure 13 Compared to the LED light-emitting device shown, the main difference is that the semi-transparent layer 3 also covers the top light-emitting surface of each light-emitting unit 2, and the side of each light-emitting unit 2 is exposed to the semi-transparent layer 3. Therefore, most of the light from the side of each light-emitting unit 2 can be emitted without passing through the semi-transparent layer 3, which can also improve its light emission efficiency and ensure display brightness.

[0130] Another example structure in which the semi-transparent layer 3 is directly attached to the front side of the circuit board 1 is shown in [reference]. Figure 16 As shown, it is similar to Figure 13 Compared to the LED light-emitting device shown, the main difference is that the semi-transparent layer 3 also covers the sides and top light-emitting surfaces of each light-emitting unit 2; therefore, in this example, the coverage of the semi-transparent layer 3 is greater than that of the previous examples, and the black contrast will be relatively higher.

[0131] Of course, it should be understood that the above Figure 8 , Figures 10 to 16 The structures shown are merely examples for ease of understanding. Other equivalent variations can be made based on these; for example, see [link to example]. Figure 17 As shown, it is in Figure 14 Based on the above, a semi-transparent layer 3 is further provided on top of the second encapsulation layer 42, that is... Figure 17 The example shown includes a double semi-transparent layer 3 to further enhance contrast. Of course, to ensure light extraction efficiency, the transmittance and blackness of each semi-transparent layer 3 can be adjusted accordingly when setting the double semi-transparent layer 3, which will not be elaborated here.

[0132] For ease of understanding, this embodiment will use the fabrication method of the semi-transparent layer shown in the above examples as an example to illustrate the process. Please refer to [link / reference]. Figure 18 As shown, it includes, but is not limited to:

[0133] S2021: A reflective layer is formed on the carrier surface of the substrate using vacuum ion plating or evaporation processes. For ease of understanding, a vacuum ion plating example is provided below. In one example, under a vacuum magnetic flux environment, a magnetic field guides ions to bombard a pre-defined reflective material substrate, uniformly sputtering the molecules of this reflective material substrate onto the corresponding area of ​​the carrier surface to form a reflective layer. It should be understood that the carrier in this embodiment can be a circuit board, and the carrier surface can be the front side of the circuit board; when a first encapsulation layer is provided on the circuit board, the carrier can be the first encapsulation layer, and the carrier surface can be the side of the first encapsulation layer away from the circuit board; of course, the carrier can also be a bonding adhesive layer disposed on a carrier film, and the carrier surface can be the side of the bonding adhesive layer away from the carrier film. Therefore, the carrier and corresponding carrier surface in this embodiment can be flexibly set according to specific application scenarios, making it flexible in manufacturing, widely applicable, and highly versatile.

[0134] S2023: A mixed adhesive is obtained by uniformly mixing micron-sized glass microspheres and nano-sized black powder in a transparent adhesive. In this step, before uniformly mixing the micron-sized glass microspheres and nano-sized black powder in the transparent adhesive, the micron-sized glass microspheres are first charged. For example, the micron-sized glass microspheres can be rubbed with a specific object to make them negatively charged. Correspondingly, the nano-sized black powder also carries a negative charge, for example, carbon black powder is used as the nano-sized black powder. Then, the negatively charged micron-sized glass microspheres and nano-sized black powder are uniformly mixed in the transparent adhesive. The negatively charged micron-sized glass microspheres and nano-sized black powder repel each other in the transparent adhesive, thereby preventing the nano-sized black powder from adhering to the micron-sized glass microspheres.

[0135] S2025: A mixed adhesive layer is applied to the reflective layer, and the mixed adhesive layer is cured to obtain a black layer.

[0136] It should be understood that, in this embodiment, the method of setting the mixed adhesive layer on the reflective layer can be, but is not limited to, coating, molding, printing, etc.; of course, in some examples, the mixed adhesive layer can also be set on the carrier film to form a black film, and then the black film is attached to the reflective layer. It should also be understood that, because the adhesive in the mixed adhesive layer has a certain viscosity and tension, it will not flow into the gaps between the reflective particles in the reflective layer, or only a portion of the transparent adhesive will flow in, but this will not affect the formation of the first light-transmitting channel in the gaps.

[0137] For ease of understanding, this embodiment will now describe the manufacturing method of the LED light-emitting device shown in the above examples, as an example. See [link / reference]. Figure 19 As shown, it includes, but is not limited to:

[0138] S201: Several light-emitting units are arranged on the front side of the circuit board, and the electrodes of each light-emitting unit are electrically connected to the corresponding pads; as described in the above example, the electrical connection can be made by means of, but not limited to, solder paste or conductive silver paste.

[0139] S202: A semi-transparent layer is provided on the front side of the circuit board, and the semi-transparent layer covers at least the area on the front side of the circuit board that is not covered by the orthographic projection of each light-emitting unit.

[0140] To facilitate understanding, this embodiment will be illustrated with examples of the manufacturing process of several specific LED light-emitting devices.

[0141] See Figure 20-1 As shown, the production process in this example includes, but is not limited to:

[0142] S301: Several light-emitting units 2 are disposed on the front side of the circuit board 1;

[0143] S302: A first encapsulation layer 41 is formed on the front side of the circuit board 1. In this example, the first encapsulation layer 41 is a transparent adhesive layer.

[0144] S303: A reflective layer 31 is formed on the side of the first encapsulation layer 41 away from the circuit substrate 1 by vacuum ion plating or evaporation. The thickness of the reflective layer 31 is 200 nanometers. That is, in this example, the first encapsulation layer 41 is the carrier, and the side away from the circuit substrate 1 is the carrier surface.

[0145] S304: A black layer 32 is obtained by printing, molding, or coating a mixed adhesive layer on the reflective layer 31 and then curing it; in this example, the thickness of the black layer 32 is 100 micrometers.

[0146] See Figure 20-2 As shown, the production process in this example includes, but is not limited to:

[0147] S401: Several light-emitting units 2 are disposed on the front side of the circuit board 1;

[0148] S402: A reflective layer 31 is formed on the front side of the circuit substrate 1 by vacuum ion plating or evaporation. The reflective layer 31 has a thickness of 200 nanometers and covers both the side and front sides of each light-emitting unit 2. That is, in this example, the circuit substrate 1 is the carrier and the front side of the circuit substrate 1 is the carrier surface.

[0149] S403: Print, mold, or coat a mixed adhesive layer on the reflective layer 31 and cure it to obtain a black layer 32;

[0150] S404: A second encapsulating layer 42 is formed on the black layer 32 by printing, molding or coating. In this example, the second encapsulating layer 42 contains light-converting particles and / or light-diffusing particles.

[0151] See Figure 20-3 As shown, S501 to S503 in the manufacturing process of this example are the same. Figure 20-2 The process includes steps S401 to S403; after S503, step S504 removes at least a portion of the semi-transparent layer on the top light-emitting surface of each light-emitting unit 2, and the removal method may be, but is not limited to, laser removal, grinding, or plasma etching. Then, step S505 is performed: a second encapsulating adhesive layer 42 is formed on the black layer 32 by printing, molding, or coating, and the second encapsulating adhesive layer 42 also covers each light-emitting unit 2.

[0152] See another example of setting a semi-transparent layer on the front side of a circuit board. Figure 21 As shown, it includes, but is not limited to:

[0153] S2020: A connecting adhesive layer is provided on the carrier film; the connecting adhesive layer in this embodiment can be any adhesive layer that is viscous and changes from a cured state to a semi-melted state when heated, such as, but not limited to, a heat-sensitive adhesive layer, a modified epoxy adhesive layer, or a modified silicone layer, etc., which can be flexibly adopted according to the application scenario.

[0154] S2022: A reflective layer is formed on the adhesive layer by vacuum ion plating or evaporation process. That is, in this example, the adhesive layer is the carrier, and the side of the adhesive layer away from the carrier film is the carrier surface.

[0155] S2024: Micron-sized glass microspheres and nano-sized black powder are uniformly mixed in transparent adhesive to obtain a mixed adhesive, as shown in S2023 above, and will not be repeated here.

[0156] S2026: A mixed adhesive layer is applied to the reflective layer, and the mixed adhesive layer is cured to obtain a black layer;

[0157] S2028: Remove the carrier film, cover the front side of the bonding adhesive layer onto the circuit board and perform hot pressing.

[0158] To facilitate understanding, this embodiment will be illustrated with examples of the manufacturing process of several specific LED light-emitting devices.

[0159] See Figure 22-1 As shown, the production process in this example includes, but is not limited to:

[0160] S601: Several light-emitting units 2 are disposed on the front side of the circuit board 1;

[0161] S602: A first encapsulation layer 41 is formed on the front side of the circuit board 1. In this example, the first encapsulation layer is a transparent adhesive layer.

[0162] S603: A bonding adhesive layer 51 is provided on the carrier film 50. In this example, the bonding adhesive layer can be, but is not limited to, a heat-sensitive adhesive layer, a modified epoxy adhesive layer, or a modified silicone layer.

[0163] S604: A reflective layer 31 is formed on the adhesive layer 51 by vacuum ion plating or vapor deposition; the thickness of the reflective layer 31 is 200 nanometers.

[0164] S605: A black layer 32 is obtained by printing, molding, or coating a mixed adhesive layer on the reflective layer 31 and then curing it; in this example, the thickness of the black layer 32 is 100 micrometers.

[0165] S606: Remove 50% of the carrier membrane;

[0166] S607: Cover the first encapsulating adhesive layer 41 with one side of the connecting adhesive layer 51;

[0167] S608: The adhesive layer 51 is bonded to the first encapsulating adhesive layer 41 by means of heat pressing, but not limited to heat pressing.

[0168] See Figure 22-2 As shown, the production process in this example includes, but is not limited to:

[0169] S701: Several light-emitting units 2 are disposed on the front side of the circuit board 1;

[0170] S702 to S704 are the same as S603 to S605 in the above example. In this example, the connecting adhesive layer 51 can be a modified epoxy adhesive layer or a modified silicone layer.

[0171] S705: The carrier film 50 is removed, and then one side of the adhesive layer 51 is placed over the first encapsulating adhesive layer 41 and pressed together. Of course, after S705, a second encapsulating layer can be further provided on the black layer 32 as needed.

[0172] See Figure 22-3 As shown, steps S801 to S804 in this example are similar to steps S701 to S704 in the previous example, except that the adhesive layer 51 is thicker. In step S805, after removing the carrier film 50, one side of the adhesive layer 51 is placed over the top light-emitting surface of each light-emitting unit 2. Then, in step S806, it is heated and pressed to adhere to the front side of the circuit board 1. The pressed adhesive layer 51 also serves as the first encapsulation layer. In some applications, the initial thickness of the adhesive layer 51 before pressing is set to be greater than or equal to 100 μm, and the thickness after pressing is greater than or equal to 50 μm.

[0173] In other examples of this embodiment, the positions of the reflective layer 31 and the black layer 32 on the carrier film 50 can also be interchanged; for example, the black layer 32 can be formed directly on the carrier film 50 first, and then the reflective layer 31 can be formed on the black layer 32. During bonding, one side of the reflective layer 31 is directly bonded to the front side of the circuit board 1 or the first encapsulation layer above the front side of the circuit board 1, thereby obtaining the structures in the above examples. Of course, in some application scenarios, an adhesive layer (a light-transmitting layer, such as a transparent adhesive layer) can also be provided between the reflective layer 31 and the front side of the circuit board 1 or the first encapsulation layer above the front side of the circuit board 1 to improve the bonding strength between the reflective layer 31 and the front side of the circuit board 1 or the first encapsulation layer above the front side of the circuit board 1. This variation is also within the protection scope of this invention.

[0174] As can be seen, the method for manufacturing the LED light-emitting device provided in this embodiment is simple, efficient, and highly effective.

[0175] This embodiment also provides a display screen, which includes at least one LED light-emitting device from the above embodiments. Therefore, the display screen in this embodiment is a direct-view LED display screen, which has advantages such as higher contrast. The display screen also includes a driving element, which is disposed on the back or front of the circuit board of the LED light-emitting device and electrically connected to each light-emitting unit. It should be understood that the driving element in this embodiment can drive the LED light-emitting device using an AM (Active Matrix) driving method or a PM (Passive Matrix) driving method. Furthermore, the LED display screen provided in this embodiment can be widely used in electronic devices with displays, such as mobile phones, laptops, tablets, smart wearables, eye protection products, in-vehicle terminals, and advertising display terminals.

[0176] For ease of understanding, this embodiment will use an LED display screen as an example. Figure 14 The LED light-emitting device is used as an example for illustration; see [link to example]. Figure 23 The driving element 5 of the display screen is located on the back side of the circuit board 1 and is electrically connected to each light-emitting unit 2 on the front side of the circuit board 1 to drive each light-emitting unit 2. In some application scenarios of this example, other electronic components besides the light-emitting unit 2 can also be flexibly arranged on the front and / or back side of the circuit board 1. The electronic components may include, but are not limited to, resistors, capacitors, etc., and can be selected and arranged according to application requirements.

[0177] It should be understood that the application of the present invention is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A light semi-transmissive layer, characterized in that, The semi-transparent light layer comprises a reflective layer and a black layer attached to the reflective layer, the reflective layer comprises reflective particles and gaps between the reflective particles, the gaps form first light transmission channels for light to pass through the reflective layer; The black layer comprises a transparent adhesive substrate layer, micron-sized glass microbeads distributed in the transparent adhesive substrate layer, and nanometer-sized black powder filled between the micron-sized glass microbeads, each of the micron-sized glass microbeads forms a second light transmission channel for light to pass through the black layer; The ratio of the particle size of the micron-sized glass microbeads to the thickness of the black layer is 0.8 to 1.0; The nanometer-sized black powder is deposited between the micron-sized glass microbeads to form a black light blocking unit, the black light blocking unit fully covers the micron-sized glass microbeads in the thickness direction.

2. The light semi-transmissive layer according to claim 1, wherein The thickness of the black layer is 50 microns to 100 microns.

3. The light semi-transmissive layer according to claim 1 or 2, wherein The micron-sized glass microbeads are hollow structures.

4. The light semi-transmissive layer according to claim 1 or 2, wherein The volume of the micron-sized glass microbeads in the black layer is 50% to 70% of the volume of the black layer.

5. The light semi-transmissive layer according to claim 1 or 2, wherein The thickness of the reflective layer is 100 nanometers to 300 nanometers.

6. The transflector of claim 1 or 2, wherein The area of the gaps in the orthographic projection of the reflective layer is 60% to 70% of the area of the orthographic projection of the reflective layer.

7. The transflector of claim 1 or 2, wherein The side of the black layer away from the reflective layer is a non-smooth surface.

8. An LED light emitting device, characterized by, Comprise: A circuit substrate, a plurality of pads are provided on the front surface of the circuit substrate; A plurality of light emitting units are provided on the front surface of the circuit substrate, the electrodes of each light emitting unit are electrically connected to the corresponding pads; The semi-transparent light layer as claimed in any one of claims 1-7 is provided on the front surface of the circuit substrate, and covers at least the area on the front surface of the circuit substrate that is not covered by the orthographic projection of each light emitting unit.

9. The LED light emitting device of claim 8, wherein, The LED light emitting device further comprises a first encapsulation layer provided between the front surface of the circuit substrate and the semi-transparent light layer.

10. The LED light emitting device of claim 9, wherein, The semi-transparent light layer fully covers the first encapsulation layer, or the first encapsulation layer in the area directly above each light emitting unit is exposed to the semi-transparent light layer, and the other areas are covered by the semi-transparent light layer.

11. The LED light emitting device of claim 10, wherein, The semi-transparent light layer is attached to the front surface of the circuit substrate, and the LED light emitting device further comprises a second encapsulation layer provided on the semi-transparent light layer and covering each light emitting unit.

12. The LED light emitting device of claim 11, wherein, The semi-transparent light layer also covers at least one of the side surface and the top light emitting surface of each light emitting unit; the surface of the light emitting unit away from the front surface of the circuit substrate is the top light emitting surface, the surface close to the front surface of the circuit substrate is the bottom surface, and the surface between the top light emitting surface and the bottom surface is the side surface.

13. A method of manufacturing a semi-transparent layer as claimed in any one of claims 1-7, characterized in that Comprise: Forming the reflective layer on the bearing surface of the carrier by vacuum ion plating or evaporation process; Mixing the micron-sized glass microbeads and nanometer-sized black powder uniformly in transparent adhesive to obtain mixed adhesive, the micron-sized glass microbeads and the nanometer-sized black powder have the same polarity of charge to repel each other in the transparent adhesive; Providing a mixed adhesive layer on the reflective layer and curing the mixed adhesive layer to obtain the black layer.

14. A method of manufacturing a LED light emitting device as claimed in any one of claims 8-12, characterized in that Comprise: A plurality of the light emitting units are arranged on the front surface of the circuit substrate, and an electrode of each of the light emitting units is electrically connected to a corresponding pad; The semi-transparent layer is arranged on the front surface of the circuit substrate, and the semi-transparent layer covers at least a region on the front surface of the circuit substrate which is not covered by the orthographic projection of each of the light emitting units.

15. The method of producing an LED light emitting device according to Claim 14, wherein The semi-transparent layer is arranged on the front surface of the circuit substrate by: The reflective layer is formed on the front surface of the circuit substrate by a vacuum ion plating or evaporation process; The micron-sized glass microbeads and the nano-sized black powder are uniformly mixed in transparent glue to obtain mixed glue, and the micron-sized glass microbeads and the nano-sized black powder have the same polarity of electric charge to repel each other in the transparent glue; The mixed glue layer is arranged on the reflective layer, and the mixed glue layer is cured to obtain the black layer.

16. The method of producing an LED light emitting device according to Claim 15, wherein The semi-transparent layer is arranged on the front surface of the circuit substrate by: A connecting glue layer is arranged on the carrier film; The reflective layer is formed on the connecting glue layer by a vacuum ion plating or evaporation process; The micron-sized glass microbeads and the nano-sized black powder are uniformly mixed in transparent glue to obtain mixed glue, and the micron-sized glass microbeads and the nano-sized black powder have the same polarity of electric charge to repel each other in the transparent glue; The mixed glue layer is arranged on the reflective layer, and the mixed glue layer is cured to obtain the black layer; The carrier film is removed, one side of the connecting glue layer is arranged on the front surface of the circuit substrate, and the connecting glue layer is hot-pressed.

17. A display screen, characterized by The LED light emitting device as claimed in any one of claims 8-12 is arranged on the front surface or the back surface of the circuit substrate, and is electrically connected to each of the light emitting units.

Images