A display device

Abstract

The present invention discloses a display device, including a backlight module and a display panel. The backlight module includes: a circuit board, the circuit board including a plurality of pads for soldering micro light-emitting diodes; a reflective coating covering the circuit board has openings exposing the pads, and the micro light-emitting diodes are soldered within the openings. The size of the designed openings is larger than the size of the micro light-emitting diodes, so that when the micro light-emitting diodes are transferred above the corresponding openings, they can smoothly contact and be soldered to the pads within the openings. Since the circuit board usually has the problem of expansion and contraction, the size of the openings can be designed to increase by the distance that the circuit board will move during expansion and contraction on the basis of the size of the micro light-emitting diodes. In this way, even if the circuit board expands and contracts and the positions of the openings and the pads shift, the micro light-emitting diodes can still contact the pads within the openings when transferred to the original positions, realizing the electrical connection between the electrodes of the micro light-emitting diodes and the pads of the circuit board.

Description

Technical Field

[0001] The present invention relates to the field of display technologies, and particularly to a display device. Background Art

[0002] With the development of display technologies, liquid crystal display technologies have been widely used in the display field. A liquid crystal display panel itself cannot emit light and requires a backlight module to provide the brightness required for its display. Due to the limitations of the characteristics of the liquid crystal panel itself, there is a phenomenon of light leakage to varying degrees, and there is a bottleneck in improving the contrast. Therefore, a scheme for local dimming of the backlight module is proposed, which can independently control the backlight of different regions. Then, when the backlight brightness corresponding to the highlighted part in the displayed image can reach the maximum, and the backlight corresponding to the dark part in the image can be dimmed, so that the displayed image can achieve a better contrast.

[0003] Mini Light Emitting Diode (abbreviated as Mini LED) as a backlight has become a current hotspot in liquid crystal display technologies. Different from the traditional liquid crystal display that adopts the side-entry backlight scheme of a light guide plate, it uses a huge number of Mini LEDs as the backlight source, which can not only realize the thinning of the backlight, but also realize more refined dynamic control and improve the display effect.

[0004] Mini LEDs need to be soldered onto a circuit board by die bonding to prepare a Mini LED light board. The circuit board will undergo multiple production processes and transportation, etc., and there will be expansion and contraction phenomena, resulting in inevitable offset of the pads on the circuit board. And the size of Mini LEDs is small, and the offset amount of the pads can already cause Mini LEDs not to be accurately soldered to the corresponding pads, resulting in poor soldering of Mini LEDs. Summary of the Invention

[0005] The present invention provides a display device to solve the problem of poor soldering of Mini Light Emitting Diodes.

[0006] The present invention provides a display device, including:

[0007] A backlight module for providing backlight;

[0008] A display panel located on the light-emitting side of the backlight module for image display;

[0009] The backlight module includes a Mini LED light board as a backlight source;

[0010] The Mini LED light board includes:

[0011] A circuit board, which has a bearing and supporting function and is used to provide power; the circuit board includes a plurality of pads for soldering micro light-emitting diodes;

[0012] A reflective coating, covering the circuit board; the reflective coating includes a plurality of openings exposing the pads;

[0013] Micro light-emitting diodes, soldered on the pads within the openings;

[0014] Wherein, the size of the opening is larger than the size of the micro light-emitting diode, and the size of the opening meets the requirements for soldering the micro light-emitting diode after the circuit board expands and contracts.

[0015] In a possible implementation manner, in the above display device provided by the present invention, both the circuit board and the micro light-emitting diodes are rectangular;

[0016] The long side of the micro light-emitting diode is parallel to the short side of the circuit board.

[0017] In a possible implementation manner, in the above display device provided by the present invention, the openings of the reflective coating are rectangular;

[0018] The long side of the opening is parallel to the long side of the micro light-emitting diode.

[0019] In a possible implementation manner, in the above display device provided by the present invention, the long side dimension of the circuit board, the short side dimension of the opening, and the short side dimension of the micro light-emitting diode satisfy the following relationship:

[0020]

[0021] Wherein, Py represents the length of the short side of the opening, Cy represents the length of the short side of the micro light-emitting diode, and Ly represents the length of the long side of the circuit board.

[0022] In a possible implementation manner, in the above display device provided by the present invention, the long side dimension of the micro light-emitting diode and the long side dimension of the opening satisfy the following relationship:

[0023] Cx < Px ≤ Cx + d;

[0024] Wherein, Cx represents the length of the long side of the micro light-emitting diode, Px represents the length of the long side of the opening, and d represents the length of the electrode of the micro light-emitting diode in the direction parallel to the long side of the micro light-emitting diode.

[0025] In a possible implementation, in the above-mentioned display device provided by the present invention, the backlight module includes a plurality of micro-LED light boards, and the circuit boards of the micro-LED light boards are arranged in a direction parallel to the short side of the circuit board.

[0026] In a possible implementation, in the display device provided by the present invention, the size of the micro light emitting diode is 50 μm-300 μm.

[0027] In a possible implementation, in the above-mentioned display device provided by the present invention, the length of the circuit board is 200 mm-800 mm, and the width of the circuit board is 100 mm-500 mm.

[0028] In a possible implementation, in the above display device provided by the present invention, the backlight module further includes:

[0029] A protective layer covers the reflective coating and the surface of the micro-light emitting diode facing away from the circuit board.

[0030] In a possible implementation, in the above display device provided by the present invention, the backlight module further includes:

[0031] A transparent substrate, located on a side of the protective layer away from the circuit board;

[0032] A diffusion plate, located on a side of the transparent substrate away from the protective layer;

[0033] The optical film is located on a side of the diffusion plate away from the transparent substrate.

[0034] The beneficial effects of the present invention are as follows:

[0035] The display device provided by the present invention includes: a backlight module for providing backlight; a display panel located on the light-emitting side of the backlight module for image display; the backlight module includes: a micro-LED light board as a backlight source; the micro-LED light board includes: a circuit board with a bearing and supporting function for providing power; the circuit board includes a plurality of pads for soldering micro-LEDs; a reflective coating covering the circuit board; the reflective coating includes a plurality of openings exposing the pads; micro-LEDs soldered on the pads within the openings; wherein, the size of the opening is larger than the size of the micro-LED, and the size of the opening meets the requirements for soldering the micro-LED after the circuit board expands and contracts. Designing the size of the opening to be larger than the size of the micro-LED can ensure that when the micro-LED is transferred above the corresponding opening, it can smoothly contact and be soldered to the pad within the opening. Since the circuit board usually has the problem of expansion and contraction, the size of the opening can be designed to increase by the distance that the circuit board will move when it expands and contracts on the basis of the size of the micro-LED. In this way, even if the circuit board expands and contracts and the positions of the opening and the pad shift, the micro-LED can still contact the pad within the opening when it is transferred to the original position, realizing the electrical connection between the electrodes of the micro-LED and the pads of the circuit board. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required to be used in the embodiments of the present invention. Obviously, the following introduced drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained according to these drawings.

[0037] Figure 1 It is a schematic cross-sectional structure diagram of the display device provided by the embodiment of the present invention;

[0038] Figure 2 It is a schematic cross-sectional structure diagram of the Mini LED light board provided by the embodiment of the present invention;

[0039] Figure 3 It is a schematic top view structure diagram of the Mini LED light board provided by the embodiment of the present invention;

[0040] Figure 4 It is a schematic top view relationship diagram of the opening and the micro-LED provided by the embodiment of the present invention;

[0041] Figure 5 It is a schematic side view relationship diagram of the opening and the micro-LED provided by the embodiment of the present invention;

[0042] Figure 6 It is a schematic top view structure diagram of multiple Mini LED light boards provided by the embodiment of the present invention;

[0043] Figure 7 This is a schematic cross-sectional structure diagram of the backlight module provided by an embodiment of the present invention. Specific Embodiments

[0044] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described below in conjunction with the accompanying drawings and embodiments. However, the exemplary embodiments can be implemented in various forms and should not be construed as limited to the embodiments described herein; on the contrary, these embodiments are provided to make the present invention more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings represent the same or similar structures, and thus their repeated description will be omitted. The words expressing positions and directions described in the present invention are all illustrated by taking the accompanying drawings as examples, but can be changed according to needs, and all changes made are included in the protection scope of the present invention. The drawings of the present invention are only used to illustrate the relative position relationship and do not represent the actual scale.

[0045] Figure 1 This is a schematic structure diagram of the display device provided by an embodiment of the present invention. As Figure 1 shown, the display device provided by an embodiment of the present invention includes:

[0046] A backlight module 100 for providing backlight; the backlight module 100 can emit light uniformly within the entire light-emitting surface, and is used to provide light with sufficient brightness and uniform distribution for the display panel, so that the display panel can display images normally.

[0047] A display panel 200, located on the light-emitting side of the backlight module 100, for image display. The display panel 200 has a plurality of pixel units arranged in an array, and each pixel unit can independently control the light transmittance and color of the light incident on the pixel unit from the backlight module 100, so that the light transmitted through all the pixel units forms a displayed image.

[0048] The above-mentioned display device provided by an embodiment of the present invention can be a display device such as a liquid crystal display screen, a liquid crystal display, or a liquid crystal TV, or can also be a mobile terminal such as a mobile phone, a tablet computer, or a smart photo album. The backlight module is used to provide backlight in the display device, and the display panel modulates the light emitted by the backlight module to achieve image display. The backlight module provided by an embodiment of the present invention can use a Mini LED light board as a light source. The size of the Mini LED is smaller than that of the traditional LED. Using a huge number of Mini LEDs as the backlight source can achieve more refined dynamic control and improve the dynamic contrast of liquid crystal display.

[0049] The above-mentioned backlight module 100 provided by an embodiment of the present invention includes a micro light-emitting diode light board (Mini LED light board) as the backlight source.

[0050] Figure 2 This is a schematic cross-sectional structure diagram of the Mini LED light board provided by the embodiment of the present invention. As Figure 2 shown, the MiniLED light board includes: a circuit board 11, a reflective coating 12, and a micro light-emitting diode 13;

[0051] Among them, the circuit board 11 has a bearing and supporting function and is used to provide power. In the embodiment of the present invention, the circuit board 11 is used to provide a driving electrical signal for the micro light-emitting diode 13. The micro light-emitting diode 13 and the circuit board 11 are separately manufactured. The surface of the circuit board 11 includes a plurality of pads p for soldering the micro light-emitting diode. After the micro light-emitting diode 12 is manufactured, the micro light-emitting diode 13 is transferred above the pads of the circuit board 11, and the micro light-emitting diode 13 is soldered on the circuit board 11 through processes such as reflow soldering. Thus, by controlling the input signal of the circuit board 11, the micro light-emitting diode 13 can be driven to emit light.

[0052] In specific implementation, the circuit board 11 can be a printed circuit board (Printed Circuit Board, abbreviated as PCB). The PCB includes electronic circuits and an insulating layer. The insulating layer exposes the pads for soldering the micro light-emitting diode 12 in the electronic circuit and covers the rest.

[0053] Alternatively, the circuit board 11 can also be an array substrate formed by manufacturing a thin-film transistor driving circuit on a substrate. The surface of the array substrate has connection electrodes (i.e., the pads within the above-mentioned openings) connected to the thin-film transistor driving circuit, and the electrodes of each micro light-emitting diode 12 are soldered to the corresponding connection electrodes one by one. The substrate or substrate of the above circuit board 11 can be made of a flexible material to form a flexible display device.

[0054] In the embodiment of the present invention, the circuit board 11 is plate-shaped and is generally rectangular or square. The length of the circuit board 11 is between 200 mm and 800 mm, and the width is between 100 mm and 500 mm. According to the size of the display device, the backlight module can include multiple circuit boards 11, and the circuit boards 11 provide backlight through a splicing method. To avoid optical problems caused by the splicing of the circuit boards 11, the seams between adjacent circuit boards 11 should be made as small as possible, or even seamless splicing can be achieved.

[0055] The reflective coating 12 covers the circuit board 11. The reflective coating 12 can be a protective layer located above the circuit board 11. When a material with reflective properties is coated on the surface of the circuit board 11, this protective layer also has a reflective function and can reflect the light incident on the circuit board 11 side back, thereby improving the utilization efficiency of light. In the embodiment of the present invention, the reflective coating 12 can use materials such as white oil.

[0056] Figure 3 The top view structural schematic diagram of the Mini LED light board provided by the embodiment of the present invention is shown as Figure 3 shown. After the circuit board is wired, a reflective coating 12 is coated on its surface, and the position where the pad p for welding the micro light-emitting diode is exposed through processes such as etching, forming an opening window 121 as Figure 3 shown. After the opening window 121 is formed, the micro light-emitting diode 13 is welded to the corresponding pad p on the circuit board, so that the micro light-emitting diode 13 is welded to the circuit board 11.

[0057] The micro light-emitting diode 13 is welded to the pad p within the opening window 121. The micro light-emitting diode 13 is different from an ordinary light-emitting diode, and specifically refers to a micro light-emitting diode chip. Since the size of the micro light-emitting diode 13 is very small, the light-emitting chip is beneficial to control the dynamic light emission into smaller partitions, which is beneficial to improving the contrast of the picture. In the embodiment of the present invention, the micro light-emitting diode 13 can be a monochromatic micro light-emitting diode, and the size is between 50μm and 300μm.

[0058] The micro light-emitting diode 13 usually includes two electrodes, which need to be welded to two adjacent pads p on the circuit board 11 respectively. Before welding, the micro light-emitting diode 13 can be moved above its corresponding pad by means of mechanical transfer. The robotic arm for transferring the micro light-emitting diode 12 will transfer the micro light-emitting diode 13 to the corresponding position above the circuit board 11 according to the nominal value of the opening window on the circuit board 11. However, the substrate of the circuit board 11 usually uses a resin material, and after the circuit board 11 undergoes various process steps and transportation and other treatments, it is prone to the problem of expansion and contraction. Then, the opening window on the reflective coating will shift with the expansion and contraction of the circuit board, while the micro light-emitting diode 13 will still move according to the opening window position on the standard circuit board. Since the size of the micro light-emitting diode 13 is in the micron order, a very small shift of the opening window on the circuit board 11 will cause the problem that the micro light-emitting diode 13 cannot be aligned with the pad within the opening window, resulting in poor welding of the micro light-emitting diode.

[0059] In order to overcome the above problems, in the embodiment of the present invention, as Figure 2 and Figure 3 shown, the size of the opening window 121 on the reflective coating 12 can be appropriately enlarged, so that the size of the opening window 121 is larger than the size of the micro light-emitting diode 13, and the size of the opening window 121 meets the requirements for welding the micro light-emitting diode after the expansion and contraction of the circuit board 11.

[0060] In specific implementation, the size of the opening window 121 can be designed to be larger than the size of the micro light-emitting diode 13, so as to ensure that when the micro light-emitting diode is transferred above the corresponding opening window 121, it can smoothly contact and weld with the pad p in the opening window 121. Since the circuit board 11 usually has the problem of expansion and contraction, the size of the opening window 121 can be designed to increase by the distance that the circuit board 11 will move during expansion and contraction on the basis of the size of the micro light-emitting diode 13. In this way, even if the circuit board 11 expands and contracts and the positions of the opening window and the pad shift, the micro light-emitting diode can still contact the pad p in the opening window when transferred to the original position, realizing the electrical connection between the electrodes of the micro light-emitting diode and the pad of the circuit board.

[0061] During the manufacturing process, considering the difficulty of the process and the shape requirements of the product, such as Figure 3 shown, the circuit board 11 and the micro light-emitting diode 13 are usually designed as regular rectangles.

[0062] Welding micro light-emitting diodes on the circuit board forms a micro light-emitting diode light board. Currently, the display devices used, whether it is a computer display screen, a TV or a mobile phone, etc., are generally rectangles. Therefore, the driving circuit board of the micro light-emitting diode light board as a backlight source will also be made into a rectangle.

[0063] The micro light-emitting diodes are not formed one by one separately during manufacturing, but are cut after growing epitaxial layers and other structures on the substrate. The cutting accuracy directly affects the accuracy of the micro light-emitting diodes. Therefore, to simplify the process, the micro light-emitting diodes are cut into rectangles.

[0064] The expansion and contraction of the circuit board are affected by the materials used. Generally, the expansion and contraction ratio is within a certain range, and the degree of expansion and contraction is positively correlated with the length in that direction. Taking a circuit board with a length of 400 mm and a width of 200 mm as an example, the expansion and contraction of the circuit board 11 in the length direction may reach 80 μm - 200 μm, while the expansion and contraction in the width direction may reach 40 μm - 100 μm. That is to say, the offset of the opening window of the circuit board 11 in the length direction of the circuit board will be greater than its offset in the width direction.

[0065] To ensure the soldering yield of the micro light-emitting diodes, the long side of the micro light-emitting diode 13 is set parallel to the short side of the circuit board 11. The circuit board 11 has a relatively large expansion and contraction amount in the direction of the long side, and the window opening will have a relatively large offset in the direction of the long side of the circuit board. The offset of the window opening has a relatively small impact on the short side of the micro light-emitting diode 13 compared to the long side. This is because even if the window opening is offset by a large distance, the short side of the micro light-emitting diode can still be located within the window opening, so that it will not affect the contact between the electrodes of the micro light-emitting diode and the pads within the window opening, and can improve the problem of poor soldering of the micro light-emitting diode.

[0066] As Figure 3 shown, in order to adapt to the shape of the micro light-emitting diode 13, the window opening 121 of the reflective coating 12 can also be correspondingly set as a rectangle. And the long side of the window opening 121 is set parallel to the long side of the micro light-emitting diode 13.

[0067] Theoretically, the size of the window opening 121 is equal to the size of the micro light-emitting diode 13, so that the electrodes of the micro light-emitting diode 13 are connected to the pads p within the window opening 121. Considering problems such as the expansion and contraction of the circuit board 11 and the errors generated during the transfer process, the size of the window opening 121 can be correspondingly enlarged on the basis of the size of the micro light-emitting diode 13, so that even if the above problems occur, it can be ensured that the micro light-emitting diode 13 can be arranged inside the window opening 121. The sizes of both the micro light-emitting diode 13 and the window opening 121 are in the micron order of magnitude. The long side of the window opening 121 is parallel to the long side of the micro light-emitting diode 13, and the short side of the window opening 121 is parallel to the short side of the micro light-emitting diode 13, which can make the size of the window opening 121 adapt to the shape of the micro light-emitting diode and will not cause waste of occupied space, and more micro light-emitting diodes can be arranged on the circuit board.

[0068] Figure 4 The schematic top view relationship diagram of the window opening and the micro light-emitting diode provided by the embodiment of the present invention Figure 2 and Figure 3 shows the size relationship among the circuit board 11, the window opening 121 and the micro light-emitting diode 13. As Figure 2 shown, the length of the long side of the circuit board 11 is Ly, and the length of the short side of the circuit board is Lx; the length of the long side of the window opening 121 is Px, and the length of the short side of the window opening 121 is Py; as Figure 3 shown, the length of the long side of the micro light-emitting diode 13 is Cx, and the length of the short side of the micro light-emitting diode 13 is Cy.

[0069] Considering the problem of window opening offset caused by the expansion and contraction of the circuit board, in the embodiment of the present invention, the long side size of the circuit board 11, the short side size of the window opening 121 and the short side size of the micro light-emitting diode 13 can satisfy the following relationship:

[0070]

[0071] Wherein, Py represents the length of the short side of the window opening, Cy represents the length of the short side of the micro light-emitting diode, and Ly represents the length of the long side of the circuit board.

[0072] The expansion and contraction amount of the circuit board 11 in the long side direction is related to the length in the long side direction. Due to the different materials used for the circuit board 11, the degree of expansion and contraction is also different. If the expansion and contraction ratio of the circuit board material is Then the offset amount of the window opening 121 on the circuit board in the long side direction of the circuit board can reach If it is desired that the micro light-emitting diode 13 can still be located within the corresponding window opening 121 and in contact with the pads in the window opening 121 after being transferred to the original position when the window opening generates an offset, then the length of the short side of the window opening 121 should be increased by the offset amount in the long side direction of the circuit board 11 on the basis of the length of the short side of the micro light-emitting diode 13. Therefore, setting the short side dimensions of the micro light-emitting diode 13 and the window opening 121 to satisfy the above relationship can ensure that when the window opening 121 generates an offset, the corresponding micro light-emitting diode 13 can still be transferred into the window opening 121.

[0073] The dimensions of the long side of the micro light-emitting diode 13 and the long side of the window opening 121 can satisfy the following relationship:

[0074] Cx < Px ≤ Cx + d;

[0075] Wherein, Cx represents the length of the long side of the micro light-emitting diode, Px represents the length of the long side of the window opening, and d represents the length of the electrode of the micro light-emitting diode in the direction parallel to the long side of the micro light-emitting diode.

[0076] The micro light-emitting diode 13 includes two electrodes, which are respectively welded to the two pads p in the corresponding window opening 121. Figure 5 This is a schematic side view relationship diagram of the window opening and the micro light-emitting diode provided by the embodiment of the present invention, as Figure 5As shown, there is a certain gap between the two pads p in the opening 121. This is because there is also a gap between the two electrodes of the micro light-emitting diode 13, and the length of this gap along the long side direction of the micro light-emitting diode 13 accounts for about one-third of the long side. Then, when manufacturing the circuit board 11, the gap between the two pads connecting the same micro light-emitting diode is made to adapt to the gap between the two electrodes of the micro light-emitting diode. There is also an offset phenomenon in the opening 121 of the circuit board along the short side direction of the circuit board 11. Therefore, it is necessary to consider the dimensions of the long side direction of the micro light-emitting diode 13 and the opening 121, and in the case where the opening 121 is offset, the two electrodes of the micro light-emitting diode 13 can be connected to the two pads p in the corresponding opening 121.

[0077] In the embodiment of the present invention, the length Px of the long side of the opening 121 is set to be greater than the length Cx of the long side of the micro light-emitting diode 13. In addition, the length d of the electrode of the micro light-emitting diode 13 along the long side direction of the micro light-emitting diode is about one-third of the long side of the micro light-emitting diode, and this electrode length d can already meet the offset amount of the opening 121. Therefore, the length Px of the long side of the opening 121 can be set to satisfy Cx < Px ≤ Cx + d.

[0078] In specific applications, the size of the micro light-emitting diode light board is not too large. Therefore, the micro light-emitting diode needs to be transferred to the circuit board after being manufactured and then welded. The yield of the micro light-emitting diode light board depends on the yield of the micro light-emitting diodes on the light board. Therefore, the larger the size of the light board, the lower its production yield. Therefore, currently, the backlight module applied in large-size display devices can be set by splicing multiple Mini LED light boards with each other.

[0079] Figure 6 It is a top view structural schematic diagram of multiple Mini LED light boards provided by the embodiment of the present invention. As Figure 6 shown, the backlight module provided by the embodiment of the present invention includes multiple micro light-emitting diode light boards, and the circuit boards 11 of each micro light-emitting diode light board are arranged along the direction parallel to the short side of the circuit board.

[0080] In specific implementation, the conventional display screen size is 16:9, and due to the range of the Mini LED die bonding equipment and the size of the display, it is not convenient to splice with square light boards. Therefore, the circuit board 11 can be designed as a rectangle, and the ratio of the long side to the short side is close to 2:1. When the size of the circuit board 11 is smaller than the size of the required illumination range, the number of circuit boards 11 arranged can be increased along the short side direction of the circuit board 11.

[0081] In the above display device provided by the embodiment of the present invention, as Figure 2As shown, the Mini LED provided by the embodiment of the present invention further includes:

[0082] The protection layer 14 covers the surface of the reflective coating 12 and the micro-LED 13 facing away from the circuit board 11 .

[0083] The function of the protective layer 14 is to encapsulate the micro-LED 13, thereby effectively preventing the micro-LED from falling off, getting wet, and other unfavorable conditions. The material used for the protective layer 14 includes silica gel, epoxy resin, or other colloid materials with high transmittance. In practical applications, the protective layer 14 can be formed on the surface of the micro-LED 13 by spraying or spot coating. Figure 2 The backlight module shown in the figure adopts the whole-surface spraying method to make the above-mentioned protective layer 14, and the whole-surface spraying method has higher production efficiency. In actual application, the micro-LED 13 can also be encapsulated by applying colloidal material on the micro-LED 13. The dot-coating encapsulation method can save colloidal material, and the amount of glue can be flexibly controlled, which is more applicable.

[0084] Figure 7 A schematic diagram of a cross-sectional structure of a backlight module provided in an embodiment of the present invention is shown in FIG. Figure 7 As shown, the backlight module provided by the embodiment of the present invention further includes: a transparent substrate 15 , a diffusion plate 16 and an optical film 17 .

[0085] The transparent substrate 15 is located on the side of the protective layer 14 away from the circuit board 11. The transparent substrate 15 allows the light from the micro-LED 13 to pass through and is used to support the diffuser 16. The material of the transparent substrate 15 can be selected from polymethyl methacrylate or polycarbonate. The transparent substrate 15 serves as a supporting structure for the diffuser 16, so that the light emitted by the micro-LED 13 is fully mixed before reaching the diffuser 16. In the embodiment of the present invention, the thickness of the transparent substrate 15 meets the mixing distance of the micro-LED 13 to ensure the backlight effect. In a specific implementation, the thickness of the transparent substrate 15 is not more than 10 mm.

[0086] The diffuser 16 is located on the side of the transparent substrate 15 away from the protective layer 14. The diffuser 16 is usually provided with scattering particle materials. After the light enters the diffuser 16, the scattering material causes the light to be refracted and reflected continuously, thereby achieving the effect of breaking up the light and further achieving the effect of uniform light. The material used for the diffuser is generally selected from at least one of polymethyl methacrylate PMMA, polycarbonate PC, polystyrene material PS, and polypropylene PP, which is not limited here.

[0087] The optical film sheet 17 is located on the side of the diffusion plate 16 facing away from the transparent substrate 15. The optical film sheet group 17 may include one or more of a prism sheet, a quantum dot film sheet, a reflective polarizer, etc. The purpose of adding these film sheets in the backlight module is to enable the backlight module to adapt to a variety of practical applications. For example, the prism sheet can change the exit angle of light, thereby changing the viewable angle of the display device. The quantum dot film can provide quantum dot emission with higher monochromaticity and is applied to quantum dot TVs to improve the display color gamut of the TVs. The reflective polarizer can improve the utilization rate of light and at the same time make the exit light have the property of polarization, omitting the use of the lower polarizer of the liquid crystal display panel.

[0088] The display device provided by the embodiment of the present invention includes: a backlight module for providing backlight; a display panel located on the light exit side of the backlight module for image display; the backlight module includes: a micro light-emitting diode light board as a backlight source; the micro light-emitting diode light board includes: a circuit board having a carrying and supporting function for providing power; the circuit board includes a plurality of pads for soldering micro light-emitting diodes; a reflective coating covering the circuit board; the reflective coating includes a plurality of openings exposing the pads; micro light-emitting diodes soldered on the pads within the openings; wherein, the size of the opening is larger than the size of the micro light-emitting diode, and the size of the opening meets the requirements for soldering the micro light-emitting diode after the circuit board expands and contracts. Designing the size of the opening to be larger than the size of the micro light-emitting diode can ensure that when the micro light-emitting diode is transferred above the corresponding opening, it can smoothly contact and be soldered to the pad within the opening. And because the circuit board usually has the problem of expansion and contraction, the size of the opening can be designed to increase the distance that the circuit board will move when it expands and contracts on the basis of the size of the micro light-emitting diode. In this way, even if the circuit board expands and contracts and the positions of the opening and the pad shift, the micro light-emitting diode can still contact the pad within the opening when it is transferred to the original position, realizing the electrical connection between the electrodes of the micro light-emitting diode and the pads of the circuit board.

[0089] Although the preferred embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications to these embodiments once they know the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present invention.

[0090] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these modifications and variations.

Claims

1. A display device, characterized in that, include: A backlight module, used for providing backlight; A display panel, located at the light-emitting side of the backlight module, for image display; The backlight module includes a micro light emitting diode light panel as a backlight source; The micro light emitting diode light board comprises: A circuit board, having a bearing and supporting function and used for providing power; the circuit board includes a plurality of pads for soldering micro light emitting diodes; A reflective coating covering the circuit board; the reflective coating comprising a plurality of openings exposing the pads; A micro light emitting diode is soldered to a soldering pad in the window; Wherein, the size of the window is larger than the size of the micro light emitting diode, and the size of the window meets the requirement of welding the micro light emitting diode after the circuit board expands and contracts; The window and the micro-LED are both rectangular; the size of the long side of the micro-LED and the size of the long side of the window satisfy the following relationship: Cx <Px≤Cx+d; Wherein, Cx represents the length of the long side of the micro-LED, Px represents the length of the long side of the window, and d represents the length of the electrode of the micro-LED in the direction parallel to the long side of the micro-LED; There is a gap between the pads in the window, and the length of the gap accounts for one third of the long side of the micro light emitting diode.

2. The display device according to claim 1, wherein The circuit board is rectangular; The long side of the micro light emitting diode is parallel to the short side of the circuit board.

3. The display device according to claim 2, characterized in that, The long side of the window is parallel to the long side of the micro light emitting diode.

4. The display device according to claim 3, wherein The size of the long side of the circuit board, the size of the short side of the window, and the size of the short side of the micro light emitting diode satisfy the following relationship: Wherein, Py represents the length of the short side of the window, Cy represents the length of the short side of the micro light emitting diode, and Ly represents the length of the long side of the circuit board.

5. The display device according to claim 2, wherein The backlight module includes a plurality of micro light emitting diode light boards, and the circuit boards of the micro light emitting diode light boards are arranged in a direction parallel to the short side of the circuit board.

6. The display device according to any one of claims 1 to 5, characterized in that, The size of the micro light emitting diode is 50 μm-300 μm.

7. The display device according to any one of claims 1 to 5, characterized in that The length of the circuit board is 200mm-800mm, and the width of the circuit board is 100mm-500mm.

8. The display device according to any one of claims 1-5, characterized in that, The backlight module also includes: A protective layer covers the reflective coating and the surface of the micro-light emitting diode facing away from the circuit board.

9. The display device according to claim 8, characterized in that The backlight module also includes: A transparent substrate, located on a side of the protective layer away from the circuit board; A diffusion plate, located on a side of the transparent substrate away from the protective layer; The optical film is located on a side of the diffusion plate away from the transparent substrate.

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