Manufacturing method of display module, display module and display device
By using a combination method of composite black optical film and transparent protective film in Mini COB display module, the problem of black hot melt adhesive residue is solved, the light output consistency and brightness uniformity of the LED chip are achieved, and the display module is improved. Display effect.
Patent Information
- Application Number
- CN202411451351.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2024-07-29
- Filing Date
- 2024-10-17
- Publication Date
- 2025-01-14
AI Technical Summary
In the prior art, the black hot melt adhesive of the Mini COB display module remains on the surface of the LED chip, affecting the brightness and uniformity of the light, resulting in poor display consistency.
By combining a composite black optical film and a transparent protective film, the composite black optical film is covered and pressed on the lamp plate, the ejected light surface of the light emitting element penetrates the black optical layer to prevent the black optical layer from remaining on the surface of the light emitting element. And extrusion is carried out under heating and negative pressure environments to ensure the flatness and sealing of the optical layer.
The light-emitting element has been achieved with excellent consistency in light-emitting effects, avoiding the residue of the black optical layer, and improving the blackness and brightness uniformity of the display module.
Smart Images
Figure CN119314983A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of display technology, and in particular to a manufacturing method of a display module and a display module. Background Art
[0002] Mini COB (Chip On Board) display module uses COB packaging to directly solder LED (light-emitting diode) chips to the PCB board using solder paste. However, due to the process capability of the PCB board, the PCB pad is larger than the LED chip pad, resulting in solder paste leaking from the chip pad after soldering. The Mini COB display screen is silver-gray when the screen is off. Currently, one of the more mainstream methods to improve the black consistency of the off-screen is to use thermal lamination technology to press the black hot-melt adhesive film directly onto the PCB through heating and pressurization to cover the color of the PCB, pads and solder paste to achieve the purpose of overall blackening. However, the prior art directly sets the black hot-melt adhesive film on the PCB surface, and there is a probability that the black hot-melt adhesive will remain on the light-emitting surface of the LED chip, which will affect the brightness and uniformity of the LED light. In addition, after the positive and negative electrodes of the LED chip are fixed to the PCB board by solder paste and other solid crystal materials, some LED chips may have different degrees of inclination, resulting in inconsistent flatness between the upper surfaces of each LED chip, and the black hot-melt adhesive directly pressed onto the PCB board will also remain inconsistent on the surface of the LED chip, resulting in large differences in the light emission from the upper surfaces of each LED chip.
[0003] Therefore, how to reduce the black hot melt adhesive residue on the surface of the LED chip to ensure the display blackness of the display module and the display consistency of each LED chip is an urgent problem to be solved. Summary of the invention
[0004] In view of the deficiencies of the above-mentioned related technologies, the purpose of the present application is to provide a method for manufacturing a display module, a display module and a display device, aiming to solve the problem in the prior art that black hot melt adhesive residues remain on the light-emitting surface of the display module, resulting in poor display consistency.
[0005] The present invention provides a method for manufacturing a display module, comprising: providing a light board, a composite black optical film and a transparent protective film; wherein the light board comprises a substrate, and a plurality of light-emitting elements arranged on the substrate; the composite black optical film comprises a black optical layer and an upper light-transmitting layer and a lower light-transmitting layer respectively covering the upper surface and the lower surface of the black optical layer; firstly covering and pressing the composite black optical film on the light board so that the top light-emitting surfaces of the plurality of light-emitting elements at least penetrate the black optical layer of the composite black optical film, and then covering and pressing the transparent protective film on the upper surface of the composite black optical film so that the upper surface of the transparent protective film is a flat surface.
[0006] According to the manufacturing method of the display module provided by the present invention, the black optical layer in the composite black optical film is squeezed by the top of the light-emitting element, the lower light-transmitting layer and the upper light-transmitting layer, so that the tops of multiple light-emitting elements penetrate the black optical layer, which can prevent the black optical layer from remaining on the top of the light-emitting element and blocking the light-emitting surface of the light-emitting element, thereby making the light-emitting effect of the light-emitting element consistent and having the advantage of simple manufacturing.
[0007] In one embodiment, when the composite black optical film is covered and pressed onto the lamp board, the composite black optical film is pressed onto the lamp board under negative pressure and heating environment and under the action of extrusion force, so that the composite black optical film softens so that the top light-emitting surfaces of multiple light-emitting elements penetrate the black optical layer under the extrusion force.
[0008] In one embodiment, when the transparent protective film is covered and pressed onto the upper surface of the composite black optical film, the transparent protective film is pressed onto the composite black optical film under negative pressure and heating environment and under the action of extrusion force.
[0009] In one embodiment, the transparent protective film and the upper light-transmitting layer of the composite black optical film are made of the same material; after the transparent protective film is covered and pressed onto the upper surface of the composite black optical film, the transparent protective film and the upper light-transmitting layer of the composite black optical film are integrated.
[0010] In one embodiment, the composite black optical film is covered and pressed onto the light board so that when the top light-emitting surfaces of the multiple light-emitting elements penetrate the lower light-transmitting layer and the black optical layer of the composite black optical film, the multiple light-emitting elements do not penetrate the upper light-transmitting layer of the composite black optical film.
[0011] The present invention further provides a display module, the display module comprising: A substrate, a surface of which is provided with a plurality of light-emitting elements; The substrate is provided with a lower light-transmitting layer, the lower light-transmitting layer is provided with a black optical layer, and a transparent protective layer is provided above the black optical layer; wherein: The lower light-transmitting layer at least covers the region between the plurality of light-emitting elements on the top surface of the substrate, and the top surface of the lower light-transmitting layer in the region between the plurality of light-emitting elements is lower than the top surfaces of the plurality of light-emitting elements; The black optical layer covers the top surface of the lower light-transmitting layer, and the top surface of the black optical layer is lower than the top surfaces of the plurality of light-emitting elements; The transparent protective layer covers the top surface of the black optical layer and the top surfaces of the plurality of light emitting elements; The plurality of light emitting elements press the lower light-transmitting layer and the black optical layer, so that the lower light-transmitting layer and the black optical layer are upwardly tilted around the plurality of light emitting elements, and the plurality of light emitting elements at least penetrate the black optical layer.
[0012] In the display module provided by the present invention, since multiple light-emitting elements squeeze the lower light-transmitting layer and the black optical layer and multiple light-emitting elements penetrate the black optical layer, the black optical layer will not remain on the top surface of the light-emitting element, so that the light-emitting effect of each light-emitting element is consistent.
[0013] In one embodiment, the black optical layer is not in contact with the plurality of light emitting elements; surfaces of the plurality of light emitting elements and the black optical layer are blocked by the lower light-transmitting layer.
[0014] In one embodiment, among the plurality of light-emitting elements, each of the light-emitting elements includes at least one, at least two, at least three, or at least four or more flip-chip LED chips.
[0015] In one embodiment, the light transmittance of the black optical layer is 0-5% or 10%-30%.
[0016] The present invention further provides a display device, comprising a driving module and the above-mentioned display module, wherein the driving module is connected to the display module to drive the display module.
[0017] The above display device solves the problem of uneven light output from the display module. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figures 1 to 3 FIG. 1 is a schematic diagram of a method for manufacturing a display module provided by an embodiment of the present invention; Figure 4 and Figure 5 FIG. 1 is a schematic diagram of a cross-sectional structure of a display module provided by an embodiment of the present invention; Figure 6 FIG. 1 is a schematic diagram of a top view of a display module provided by an embodiment of the present invention; Figure 7 FIG. 1 is a schematic cross-sectional structure diagram of another display module provided by an embodiment of the present invention; Figure 8 FIG. 1 is a schematic cross-sectional structure diagram of another display module provided by an embodiment of the present invention; Fig. 9 FIG. 1 is a schematic cross-sectional structure diagram of another display module provided by an embodiment of the present invention. DETAILED DESCRIPTION
[0019] In order to facilitate the understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present application are given in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thoroughly and comprehensively understood.
[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. Embodiment 1
[0021] refer to Figure 1 and Figure 2 As shown, an embodiment of the present invention provides a method for manufacturing a display module, comprising: providing a light board 100, a composite black optical film 200 and a transparent protective film 300; wherein the light board 100 comprises a substrate 110, and a plurality of light-emitting elements 120 arranged on the substrate 110; the composite black optical film 200 comprises a black optical layer 220 and an upper light-transmitting layer 230 and a lower light-transmitting layer 210 respectively covering the upper surface and the lower surface of the black optical layer 220; Figure 1 As shown, the composite black optical film 200 is first covered and pressed onto the light board 100, so that the top light-emitting surfaces of the plurality of light-emitting elements penetrate the black optical layer 220 of the composite black optical film 200 (refer to Figure 2 ) Then, the transparent protective film 300 is covered and pressed onto the upper surface of the composite black optical film 200, and the upper surface of the transparent protective film 300 is made flat.
[0022] In this embodiment, reference Figure 6 , a plurality of light emitting elements 120 are arranged in a rectangular array on the surface of the substrate.
[0023] In the manufacturing method described above, the thickness of the black optical layer 220 in the composite black optical film 200 gradually decreases due to being squeezed by the top of the light-emitting element 120 and the lower light-transmitting layer 210 and the upper light-transmitting layer 220, so that the tops of multiple light-emitting elements 120 penetrate the black optical layer 220, which can prevent the black optical layer 220 from remaining on the top of the light-emitting element 120 and blocking the light-emitting surface of the light-emitting element 120, thereby making the light-emitting effect of the light-emitting element 120 more consistent and having the advantage of simple manufacturing.
[0024] In the above manufacturing method, there are two cases in which the tops of the multiple light-emitting elements 120 penetrate the black optical layer 220. One case is that the tops of the multiple light-emitting elements 120 first penetrate the lower light-transmitting layer 210 and then penetrate the black optical layer 220. In this case, although the light-emitting elements 120 may contact the black light-transmitting layer 220 after penetrating the lower light-transmitting layer 210, the black light-transmitting layer 220 will be squeezed during the process of penetrating the lower light-transmitting layer by the light-emitting elements 120, so that the thickness of the black light-transmitting layer 220 becomes smaller and smaller. At the same time, the black light-transmitting layer 220 will also be squeezed by the upper light-transmitting layer 230, thereby further squeezing the black light-transmitting layer, so that when the light-emitting elements 120 penetrate the black light-transmitting layer 220, no black light-transmitting layer will remain on the top of the light-emitting elements 120.
[0025] In another case, the tops of the plurality of light-emitting elements 120 penetrate the black optical layer 220 together with a portion of the lower light-transmitting layer 210. In this case, due to the barrier effect of the lower light-transmitting layer 210, the plurality of light-emitting elements 120 will not contact the black optical layer 220, and under the mutual squeezing effect of the plurality of light-emitting elements 120 and the upper light-transmitting layer 230, the tops of the plurality of light-emitting elements 120 penetrate the black optical layer 220, so that the lower light-transmitting layer 210 and the upper light-transmitting layer 230 meet at the tops of the plurality of light-emitting elements 120, so that the black optical layer 220 will not remain on the tops of the plurality of light-emitting elements 120.
[0026] As a further refinement of the above-mentioned manufacturing method, when the composite black optical film 200 is covered and pressed onto the lamp board 100, the composite black optical film 200 is pressed onto the lamp board 100 under negative pressure and heating environment and under the action of extrusion pressure, so that the composite black optical film 200 softens so that the top light-emitting surfaces of the multiple light-emitting elements 120 penetrate the black optical layer 220 under the extrusion pressure.
[0027] Under negative pressure, the composite black optical film 200 and the light board 100 are more closely attached. In combination with the heating environment, the composite black optical film 200 softens into a paste, has a certain fluidity, and can reduce bubbles between the composite black optical film 200 and the surface of the substrate. Under the extrusion force, for example, when pressure is applied to the upper light-transmitting layer 230 of the composite black optical film 200 on the upper surface of the light board, the tops of the multiple light-emitting elements 120 press the lower light-transmitting layer 210 and the black optical layer 220 upward. Since the black optical layer 220 is squeezed, it will flow to the periphery of the tops of the multiple light-emitting elements 120, so that it will not remain on the tops of the multiple light-emitting elements 120, thereby avoiding blocking the light-emitting surface of the tops of the multiple light-emitting elements 120, so that the light-emitting effect of the multiple light-emitting elements 120 is consistent. In the above steps, the lower light-transmitting layer 210 plays a role of buffering and lubrication, making it easier for the black optical layer 220 to flow to the periphery of the tops of the multiple light-emitting elements 120, so that the multiple light-emitting elements 120 penetrate the black optical layer 220 without contacting the black optical layer.
[0028] In this embodiment, the plurality of light emitting elements 120 do not penetrate the lower light-transmitting layer 210, but are lifted up by the plurality of light emitting elements 120, penetrate the black optical layer 220 together, and contact and fuse with the upper light-transmitting layer 230. In other embodiments, the plurality of light emitting elements 120 may also penetrate the lower light-transmitting layer 210 after penetrating the black optical layer 220, and a portion of the upper light-transmitting layer 230 moves downward to communicate and fuse with the lower light-transmitting layer 210.
[0029] In this embodiment, the lower light-transmitting layer 210 and the upper light-transmitting layer 230 are made of the same material, so that the lower light-transmitting layer 210 and the upper light-transmitting layer 230 are more tightly connected when in contact and fused, thereby avoiding delamination and peeling off after long-term use.
[0030] As a further refinement of the above manufacturing method, when the transparent protective film 300 is covered and pressed onto the upper surface of the composite black optical film 200, the transparent protective film 300 is pressed onto the composite black optical film 200 under negative pressure and heating environment and under the action of extrusion force.
[0031] Under the action of negative pressure, the transparent protective film 300 is more easily adhered to the upper surface of the composite black optical film 200. Combined with the heating environment, the transparent protective film 300 softens into a paste, thereby filling the uneven surface formed on the upper surface of the composite black optical film 200 and reducing the bubbles between the black optical film 200 and the transparent protective film 300, so that the outer surface of the display module finally manufactured is smooth, which can not only protect the display module but also facilitate cleaning of dust on the surface of the display module.
[0032] As a further refinement of the above manufacturing method, refer to Figure 4 and Figure 5The transparent protective film 300 and the upper light-transmitting layer 230 of the composite black optical film 200 are made of the same material; after the transparent protective film 300 is covered and pressed on the upper surface of the composite black optical film 200, the transparent protective film 300 and the upper light-transmitting layer of the composite black optical film 200 are integrated. This can prevent the transparent protective film 300 and the composite black optical film 200 from being delaminated, and has the advantage of good sealing.
[0033] As a further refinement of the above manufacturing method, the composite black optical film 200 is covered and pressed onto the light board 100, so that when the top light-emitting surfaces of the plurality of light-emitting elements 120 penetrate the lower light-transmitting layer 210 and the black optical layer 220 of the composite black optical film 200, the plurality of light-emitting elements 120 do not penetrate the upper light-transmitting layer 230 of the composite black optical film 200. Thus, there is always a protective layer on the top surface of the plurality of light-emitting elements 120.
[0034] In this embodiment, in order to make the composite black optical film 200 fit more closely with the light board 100, the thickness of the composite black optical film 200 should be as small as possible. After the thinner composite black optical film 200 is pressed with the light board 100, since multiple light-emitting elements 120 protrude from the substrate, the surface of the composite black optical film 200 is an uneven surface. Therefore, in order to allow the transparent protective film 300 to fully fill the uneven surface of the composite black optical film 200, the thickness of the transparent protective film 300 should be greater than the thickness of the composite black optical film 200.
[0035] In order to facilitate the plurality of light emitting elements 120 to penetrate the black optical layer 220 , the thickness of the black optical layer 220 is the smallest in the composite black optical film 200 . Embodiment 2
[0036] refer to Figure 5 As shown, the embodiment of the present invention further provides a display module 1000, and the display module 1000 includes: A substrate 110, with a plurality of light emitting elements 120 disposed on the surface of the substrate 110; A lower light-transmitting layer 210 is disposed on the substrate 110, a black optical layer 220 is disposed on the lower light-transmitting layer 210, and a transparent protective layer 300 is disposed above the black optical layer 220; wherein: The lower light-transmitting layer 210 at least covers the region between the plurality of light-emitting elements 120 on the top surface of the substrate 110 , and in the region between the plurality of light-emitting elements 120 , the top surface of the lower light-transmitting layer 210 is lower than the top surfaces of the plurality of light-emitting elements 120 ; The black optical layer 220 covers the top surface of the lower light-transmitting layer 210 , and the top surface of the black optical layer 220 is lower than the top surfaces of the plurality of light-emitting elements 120 ; or the top surface of the black optical layer 220 is flush with the top surfaces of the plurality of light-emitting elements 120 ; The transparent protective layer 300 covers the top surface of the black optical layer 220 and the top surfaces of the plurality of light emitting elements 120 ; In one embodiment, the plurality of light emitting elements 120 press the lower light-transmitting layer 210 and the black optical layer 220 , so that the black optical layer 220 is upwardly tilted around the plurality of light emitting elements 120 , and each light emitting element 120 at least penetrates the black optical layer 220 .
[0037] The display module 1000 provided by the present invention can be manufactured by a display module manufacturing method provided by the first embodiment, and can certainly also be manufactured by other methods.
[0038] The display module 1000 provided by the present invention has multiple light-emitting elements 120 squeezing the lower light-transmitting layer 210 and the black optical layer 220 and multiple light-emitting elements 120 penetrating the black optical layer 220, so that the black optical layer 220 will not remain on the top surface of the light-emitting element 120, so that the light-emitting effect of each light-emitting element 120 is consistent.
[0039] As an embodiment of the display module 1000, refer to Figure 7 As shown, since the multiple light-emitting elements 120 squeeze the lower light-transmitting layer 210 and the black optical layer at the same time, the lower light-transmitting layer 210 may also penetrate the black optical layer 220 under the squeezing of the light-emitting elements 120, so that the black optical layer 220 is not in contact with the multiple light-emitting elements 120; the surfaces of the multiple light-emitting elements 120 and the black optical layer 220 are blocked by the lower light-transmitting layer 210.
[0040] As an embodiment of the display module 1000, refer to Figure 7 As shown, the plurality of light emitting elements 120 include at least one flip-chip LED chip 121; the top surface of the black optical layer 120 closest to the light emitting element 120 is at least 1 / 4 or 1 / 2 lower than the height of the substrate 1210 of the flip-chip LED chip 121 (refer to Figure 7 As shown, the dotted line in the figure is 1 / 2 of the substrate height), to ensure that the black optical layer 120 will not remain on the top surface of the flip-chip LED chip 121.
[0041] As an embodiment of the display module 1000 , each of the plurality of light emitting elements 120 includes at least two, at least three, or at least four flip-chip LED chips.
[0042] refer to Fig. 9As shown, the light emitting element 120 includes three flip-chip LED chips, namely, a red LED chip 122; a blue LED chip 123 and a blue LED chip 124. Three chips of different colors form a pixel unit. Since the spacing between the three chips is very small, the composite black optical film 200 cannot be embedded in the gap between the chips. Therefore, the three chips can penetrate the black optical layer 220 as a whole. However, if the gap between the chips is large enough, the composite black optical film 200 can also be embedded in the gap between the chips.
[0043] As an embodiment of the above-mentioned display module 1000, the light transmittance of the black optical layer 120 is 0-5% or 10%-30%. When the blackness of the display module needs to be improved, the light transmittance of the black layer 4 can be set to 0-5%, that is, it is basically opaque, which can maximize the blackness of the display when the display module is not lit; or, the light transmittance of the black layer 4 can also be 10%-30%, for example, it can be 20%, in which case the black layer 4 has a certain light transmittance, which can improve the display brightness of the display module.
[0044] As an embodiment of the above display module, refer to Figure 8 The top surfaces of the plurality of light emitting elements 120 are provided with transparent protrusions, which can increase the light extraction efficiency of the plurality of light emitting elements 120 to a certain extent.
[0045] In this embodiment, the thickness of the black optical layer 120 is the smallest and the thickness of the transparent protective layer 300 is the largest in the portion between the light emitting elements, thereby facilitating the penetration of the plurality of light emitting elements 120 through the black optical layer 120 while obtaining better sealing performance. In a preferred embodiment, the thickness of the black optical layer 120 is preferably 3 μm to 10 μm.
[0046] The present invention further provides a display device (not shown), comprising a driving module and the above display module 1000 , wherein the driving module is connected to the display module 1000 to drive the display module.
[0047] The above display device solves the problem of uneven light output from the display module.
[0048] It should be understood that the application of the present invention is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.
Claims
1. A method for manufacturing a display module, characterized in that: include: Provide light board, composite black optical film and transparent protective film; The light board comprises a substrate, and a plurality of light-emitting elements arranged on the substrate; The composite black optical film includes a black optical layer and an upper light-transmitting layer and a lower light-transmitting layer respectively covering the upper surface and the lower surface of the black optical layer; the composite black optical film is first covered and pressed onto the light board so that the top light-emitting surfaces of the multiple light-emitting elements at least penetrate the black optical layer of the composite black optical film, and then the transparent protective film is covered and pressed onto the upper surface of the composite black optical film, so that the upper surface of the transparent protective film is a flat surface.
2. The manufacturing method according to claim 1, characterized in that: When the composite black optical film is covered and pressed onto the lamp board, the composite black optical film is pressed onto the lamp board under negative pressure and heating environment and under the action of extrusion force, so that the composite black optical film softens so that the top light-emitting surfaces of multiple light-emitting elements penetrate the black optical layer under the extrusion force.
3. The manufacturing method according to claim 1, characterized in that: When the transparent protective film is covered and pressed onto the upper surface of the composite black optical film, the transparent protective film is pressed onto the composite black optical film under negative pressure and heating environment and under the action of extrusion force.
4. The manufacturing method according to claim 1, characterized in that: The transparent protective film and the upper light-transmitting layer of the composite black optical film are made of the same material; after the transparent protective film is covered and pressed onto the upper surface of the composite black optical film, the transparent protective film and the upper light-transmitting layer of the composite black optical film are integrated.
5. The manufacturing method according to claim 1, characterized in that: The composite black optical film is covered and pressed onto the light board, so that when the top light-emitting surfaces of the multiple light-emitting elements at least penetrate the black optical layer of the composite black optical film, the multiple light-emitting elements do not penetrate the upper light-transmitting layer of the composite black optical film.
6. A display module, characterized in that: The display module comprises: A substrate, a surface of which is provided with a plurality of light-emitting elements; The substrate is provided with a lower light-transmitting layer, the lower light-transmitting layer is provided with a black optical layer, and a transparent protective layer is provided above the black optical layer; wherein: The lower light-transmitting layer at least covers the region between the plurality of light-emitting elements on the top surface of the substrate, and in the region between the plurality of light-emitting elements, the top surface of the lower light-transmitting layer is lower than the top surfaces of the plurality of light-emitting elements; The black optical layer covers the top surface of the lower light-transmitting layer, and the top surface of the black optical layer is lower than the top surfaces of the plurality of light-emitting elements; The transparent protective layer covers the top surface of the black optical layer and the top surfaces of the plurality of light emitting elements; The plurality of light emitting elements press the lower light-transmitting layer and the black optical layer, so that the black optical layer is upwardly tilted around the plurality of light emitting elements, and the top surfaces of the plurality of light emitting elements at least penetrate the black optical layer.
7. The display module according to claim 6, wherein: The black optical layer is not in contact with the plurality of light emitting elements; the surfaces of the plurality of light emitting elements and the black optical layer are blocked by the lower light-transmitting layer.
8. The display module according to any one of claims 6, characterized in that: Among the plurality of light-emitting elements, each light-emitting element includes at least one, at least two, at least three, or at least four or more flip-chip LED chips.
9. The display module according to any one of claims 6, characterized in that: The light transmittance of the black optical layer is 0-5% or 10%-30%.
10. A display device, characterized in that: The display device comprises a driving module and the display module according to any one of claims 6 to 9, and the driving module is connected to the display module.