Lamp panel, backlight module and display device

Abstract

The utility model discloses a lamp panel, a backlight module and a display device, the lamp panel comprises a substrate, a plurality of light-emitting elements and a reflective retaining wall, and the plurality of light-emitting elements and the reflective retaining wall are located on the surface of the substrate; the light-reflecting retaining wall surrounds the light-emitting elements, the side wall, facing the light-emitting elements, of the light-reflecting retaining wall is provided with an arc-shaped surface, and the light-reflecting retaining wall is used for reflecting light emitted by the light-emitting elements. The light-reflecting retaining wall can reflect light emitted by the light-emitting element outside the nearby display area to the position above the light-emitting element in the display area farther from the light-reflecting retaining wall, so that the light-emitting brightness of the edge of the display area is increased, and the brightness uniformity of a display picture is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of backlighting, and particularly to a lamp board, a backlight module and a display device. Background Art

[0002] Mini Light Emitting Diode (Mini LED) technology is known for its high brightness. Applying Mini LED technology to backlight modules and display devices, more precise control of the backlight can be achieved using local dimming technology, enabling high-resolution and high-contrast displays, and greatly improving the display image quality.

[0003] However, in current Mini LED display devices, there is a phenomenon of darkening at the edges of the display area, which to a certain extent destroys the brightness uniformity of the display screen and affects the user experience of the display effect. Summary of the Utility Model

[0004] The utility model provides a lamp board, a backlight module and a display device to improve the phenomenon of darkening near the edges of the display area and enhance the user experience.

[0005] In a first aspect, the utility model provides a lamp board, comprising: a substrate, a plurality of light-emitting elements and a reflective retaining wall, wherein the plurality of light-emitting elements and the reflective retaining wall are located on the surface of the substrate;

[0006] The reflective retaining wall surrounds the plurality of light-emitting elements, and the side wall of the reflective retaining wall facing the plurality of light-emitting elements has an arc-shaped surface, and the reflective retaining wall is used for reflecting the light emitted by the light-emitting elements.

[0007] In some embodiments of the utility model, in the direction perpendicular to the substrate and pointing from the substrate to the light-emitting elements, the cross-sectional area of the reflective retaining wall gradually decreases.

[0008] In some embodiments of the utility model, the arc-shaped surface satisfies the following equation:

[0009]

[0010] where x and y respectively represent the abscissa and ordinate of any point on the arc-shaped surface in a rectangular coordinate system, D1 and D2 respectively represent the minimum and maximum values of the abscissa of the points on the arc-shaped surface, k t represents the slope of the tangent line at the point with coordinates (x, y) on the arc-shaped surface, and k t satisfies the following relationship:

[0011]

[0012] Wherein, θ represents the incident angle of the light ray incident on the point with coordinates (x, y) on the arc surface, and h and a are set values.

[0013] In some embodiments of the present invention, the height of the light-reflecting retaining wall is greater than or equal to the height of the light-emitting element.

[0014] In some embodiments of the present invention, the plurality of light-emitting elements are arranged in an array along a first direction and a second direction. The distance between the light-reflecting retaining wall and the closest light-emitting element in the first direction is less than the distance between adjacent light-emitting elements in the first direction, and the distance between the light-reflecting retaining wall and the closest light-emitting element in the second direction is less than the distance between adjacent light-emitting elements in the second direction.

[0015] In some embodiments of the present invention, the material of the light-reflecting retaining wall includes one of polycarbonate doped with titanium dioxide, silver, or organosilica gel doped with titanium dioxide.

[0016] In some embodiments of the present invention, the reflectivity of the light-reflecting retaining wall is 80% - 100%.

[0017] In a second aspect, the present invention further provides a backlight module, which includes any one of the lamp boards described in the first aspect and a plurality of functional film layers. The plurality of functional film layers are located on the light-emitting side of the lamp board and are used to modulate the light emitted from the lamp board.

[0018] In some embodiments of the present invention, the light-reflecting retaining wall in the lamp board is in contact with the functional film layer.

[0019] In a third aspect, the present invention further provides a display device, which includes any one of the backlight modules described in the second aspect and a display panel. The display panel is located on the light-emitting side of the backlight module.

[0020] The beneficial effects of the present invention are as follows:

[0021] The present invention provides a lamp board, a backlight module, and a display device. Among them, the lamp board includes: a substrate, a plurality of light-emitting elements, and a light-reflecting retaining wall. The plurality of light-emitting elements and the light-reflecting retaining wall are located on the surface of the substrate; the light-reflecting retaining wall surrounds the plurality of light-emitting elements, and the side wall of the light-reflecting retaining wall facing the plurality of light-emitting elements has an arc surface. The light-reflecting retaining wall is used to reflect the light emitted by the light-emitting elements. The light-reflecting retaining wall can reflect the light emitted by the light-emitting elements outside the nearby display area to above the light-emitting elements in the display area relatively farther away from the light-reflecting retaining wall, thereby increasing the light-emitting brightness at the edge of the display area and being beneficial to improving the brightness uniformity of the display screen. Description of the Drawings

[0022] To more clearly illustrate the technical solutions of the embodiments of the present utility model, the following will briefly introduce the attached drawings required for use in the embodiments of the present utility model. Obviously, the attached drawings introduced below are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other attached drawings can also be obtained based on these attached drawings.

[0023] Figure 1 It is a schematic structural diagram of a backlight module in the related art;

[0024] Figure 2 It is a normalized brightness distribution diagram of the backlight module in the related art;

[0025] Figure 3 It is Figure 2 The normalized brightness distribution curve in the BB' direction in;

[0026] Figure 4 It is a schematic structural diagram of a lamp board provided by an embodiment of the present utility model;

[0027] Figure 5 It is a partial enlarged view of a lamp board provided by an embodiment of the present utility model;

[0028] Figure 6 It is a cross-sectional view of a backlight module provided by an embodiment of the present utility model;

[0029] Figure 7 It is a design schematic diagram of the arc surface of the reflective retaining wall provided by an embodiment of the present utility model;

[0030] Figure 8 It is a curve comparison diagram of the normalized brightness before and after setting the reflective retaining wall in the backlight module;

[0031] Figure 9 It is a scatter diagram of the normalized brightness difference before and after setting the reflective retaining wall in the backlight module;

[0032] Figure 10 It is a cross-sectional view of a display device provided by an embodiment of the present utility model.

[0033] Explanation of reference numerals:

[0034] 1 - Light board, 11 - Substrate, 12 - Light - emitting element, 13 - Reflective retaining wall, 14 - Reflective layer, 2 - Functional film layer, 21 - Diffusion plate / diffusion sheet, 22 - Light - homogenizing film, 23 - Color - conversion film, 24 - Brightness - enhancing film, 25 - Polarizing film, 3 - Light - shielding structure, AA - First region / display area, AA’ - Second region / non - display area, AA1 - Third region, AA2 - Fourth region, L1 - First part of light rays, L2 - Second part of light rays, L3 - Third part of light rays, X - First direction, Y - Second direction, 100 - Backlight module, 200 - Display panel. Detailed implementation manners

[0035] To make the above - mentioned objects, features, and advantages of the present utility model more obvious and understandable, the present utility model will be further described below with reference to the drawings and embodiments. However, the exemplary embodiments can be implemented in various forms and should not be construed as being limited to the embodiments described herein; on the contrary, these embodiments are provided to make the present utility model 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 descriptions will be omitted. The words expressing positions and directions described in the present utility model are illustrative with reference to the drawings, but can be changed according to needs, and all changes are included in the protection scope of the present utility model. The drawings of the present utility model are only used to illustrate the relative position relationship and do not represent the actual scale.

[0036] Figure 1 It is a schematic structural diagram of a backlight module in the related art.

[0037] As Figure 1 shown, the backlight module includes a light board 1 and a plurality of functional film layers 2 located on the light - emitting side of the light board 1. Among them, the light board 1 includes a substrate 11, a reflective layer 14, and a plurality of light - emitting elements 12. The plurality of light - emitting elements 12 are arranged on the surface of the substrate 11. The functional film layer 2 is used to modulate the light rays emitted from the light - emitting elements 12 into it, and can have functions such as light homogenization, brightness enhancement, and adjustment of the polarization state of light rays. Ideally, the backlight module emits surface light with a uniform intensity distribution.

[0038] However, in the edge region of the backlight module, the phenomenon of uneven light - emitting brightness distribution often occurs. Figure 1 shows the propagation path of the light rays emitted by the light - emitting element 12 closest to the edge of the light board 1. As Figure 1 shown, the light rays emitted by the light - emitting element 12 closest to the edge of the light board 1 can be divided into three parts:

[0039] The first part of the light L1 is emitted toward the side of the backlight module and does not enter the functional film layer 2 above the lamp board 1. This part of the light will leak from the side of the backlight module and cannot be effectively used for display; the second part of the light L2 is incident on the functional film layer 2 above the lamp board 1. This part of the light can be partially or completely used for display by propagating in the functional film layer 2 in the backlight module; the third part of the light L3 is emitted toward the side away from the edge of the lamp board 1, for example, it can be emitted toward the adjacent light-emitting element 12 or toward the reflective layer 14, and at least part of the third part of the light L3 can be used for display. For example, a reflective layer 14 is arranged between the substrate 11 and the light-emitting element 12, so that the light emitted by the light-emitting element 12 toward the direction of the substrate 11 can be reflected to the functional film layer 2 above the lamp board 1 for reuse.

[0040] It can be seen that the light loss caused by the leakage of the first part of the light L1 outside the backlight module will cause the brightness of the edge area of the backlight module to be lower.

[0041] Figure 2 is a normalized brightness distribution diagram of a backlight module in the related art; Figure 3 for Figure 2 Normalized brightness distribution curve in the BB' direction.

[0042] Depend on Figure 2 and Figure 3 It can be seen that the backlight module includes a first area AA and a second area AA'. When the backlight module is applied to a display device, the light emitted from the first area AA is used to form a display screen, that is, the first area AA corresponds to the display area AA of the display device, and the light emitted from the second area AA' cannot be used for display, that is, the second area AA' corresponds to the non-display area AA' of the display device. According to the different light emission brightness, the first area AA can be roughly divided into a third area AA1 and a fourth area AA2, and the light emission brightness of the third area AA1 is higher than the light emission brightness of the fourth area AA2.

[0043] Among them, since the light emitting element 12 has a large light emitting angle, the light emitted from each place in the third area AA1 is emitted by the light emitting element 12 directly below the place and multiple light emitting elements 12 around it, so that the third area AA1 can have a higher light emitting brightness and a more uniform brightness distribution. The closer to the edge of the backlight module, the fewer the number of light emitting elements 12 that can radiate to the area within the light emitting range, so the light emitting brightness of the fourth area AA2 is lower than the light emitting brightness of the third area AA1, and the light emitting brightness of the second area AA' is lower than the light emitting brightness of the fourth area AA2.

[0044] It can be seen that the arrangement of the light emitting elements 12 in the light board 1 will also result in lower light brightness near the edge of the backlight module, but the light brightness of the second area AA' does not affect the light brightness of the display area AA.

[0045] In view of this, an embodiment of the present utility model provides a light board 1, which is used to improve the light-emitting brightness of the fourth area AA2 in the backlight module, thereby improving the uniformity of the light-emitting brightness in the first area AA, and further improving the uniformity of the light-emitting brightness in the display area AA of the display device.

[0046] Figure 4 It is a schematic structural diagram of a light board provided by an embodiment of the present utility model; Figure 5 It is a partial enlarged view of a light board provided by an embodiment of the present utility model, Figure 5 showing Figure 4 an enlarged view of area Q in Figure 6 It is a cross-sectional view of a backlight module provided by an embodiment of the present utility model, Figure 6 the cross-section of the light board 1 in Figure 5 corresponds to the cross-section in the CC' direction in

[0047] As Figures 4 - 6 shown, in an embodiment of the present utility model, the light board 1 includes a substrate 11, a reflective retaining wall 13, and a plurality of light-emitting elements 12. Among them, the light-emitting elements 12 and the reflective retaining wall 13 are located on the surface of the substrate 11, and the reflective retaining wall 13 surrounds the plurality of light-emitting elements 12 for reflecting the light emitted by the light-emitting elements 12.

[0048] As Figure 6 shown, the side wall of the reflective retaining wall 13 facing the light-emitting elements 12 has an arc-shaped surface. Comparing Figure 1 and Figure 6 it can be known that the arc-shaped surface can reflect the first part of the light L1 that would originally leak out from the side of the backlight module obliquely upward, so that it enters the functional film layer 2 above the light board 1 and is utilized, thereby reducing the loss of light and improving the utilization rate of the light emitted by the light board 1.

[0049] Specifically, the substrate 11 can be one of, including but not limited to, a glass substrate or a printed circuit board (Printed Circuit Board, abbreviated as PCB). A driving circuit is provided on the substrate 11 and electrically connected to the light-emitting elements 12 to control the light-emitting elements 12 to emit light. The driving circuit is usually made of a metal material, and the metal material has a relatively high reflectivity and has a certain reflection effect on the light emitted by the light-emitting elements 12 to the side of the substrate 11 (such as Figure 1 the third part of the light L3 in

[0050] A reflective layer 14 can also be provided on the surface of the substrate 11. The reflective layer 14 can be, for example, one of, but not limited to, white reflective ink or a reflector, etc. Among them, the material of the white reflective ink can include organic solvents of polymers such as TiO2 mixed with acrylate, etc. Its reflectivity is relatively high, reaching 80% - 100%. The reflector can be made of a metal material with a relatively high reflectivity. The reflective layer 14 has openings corresponding one by one to the light-emitting elements 12. The openings are used to expose part of the structure of the driving circuit so that the light-emitting elements 12 can be connected to the driving circuit. The reflective layer 14 can be used to reflect the light emitted from one side of the substrate 11 (for example Figure 1 the third part of the light L3 in

[0051] ), improving the utilization rate of light. Multiple light-emitting elements 12 can be arranged in an array on the substrate 11 along the first direction X and the second direction Y. The distance between the light-reflecting barrier 13 and the closest light-emitting element 12 in the first direction X is less than the distance between adjacent light-emitting elements 12 in the first direction X, and the distance between the light-reflecting barrier 13 and the closest light-emitting element 12 in the second direction Y is less than the distance between adjacent light-emitting elements 12 in the second direction Y, so that the distance between the light-reflecting barrier 13 and the light-emitting elements 12 is minimized, thus meeting the design requirements of a narrow border.

[0052] The light-emitting element 12 can be a Mini LED chip, a Micro LED chip or its packaging structure. Exemplarily, as Figure 6 shown, the light-emitting element 12 includes a light-emitting chip and a packaging structure. Among them, the light-emitting chip is used for emitting light, for example, emitting blue light or white light. The packaging structure can use materials with high transmittance and high refractive index such as silicone resin. For example, the silicone resin includes components such as polysiloxane. Its refractive index is 1.4 - 1.8, and the transmittance is 92% - 100%. The packaging structure can be used to protect the internal light-emitting chip from the influence of water oxygen, impurities, etc. in the external environment on its performance. At the same time, it can adjust the angle of the light emitted by the light-emitting chip, improving the light efficiency and reducing the light crosstalk between adjacent light-emitting elements 12.

[0053] The material of the light-reflecting barrier 13 can be one of, but not limited to, polycarbonate doped with titanium dioxide, silver or organosilica doped with titanium dioxide. The reflectivity of the light-reflecting barrier 13 can reach 80% - 100%, having a good reflection effect on the incident light. The light-reflecting barrier 13 can be made by processes such as injection molding, embossing, 3D printing, etc.

[0054] The height of the reflective retaining wall 13 can be greater than or equal to the height of the light-emitting element 12, so that as much light as possible emitted by the light-emitting element 12 can be incident on the arc surface of the reflective retaining wall 13. There can be a certain gap between the reflective retaining wall 13 and the functional film layer 2 above it, or the reflective retaining wall 13 can be in contact with the functional film layer 2 above it. When the reflective retaining wall 13 is in contact with the functional film layer 2 above it, the light that would originally leak from the edge of the backlight module by the light-emitting element 12 can all be received by the arc surface of the reflective retaining wall 13, avoiding light leakage on the side of the backlight module to the greatest extent. At the same time, the reflective retaining wall 13 can also support the functional film layer 2, which is beneficial to improving the structural stability of the backlight module.

[0055] By designing the arc surface of the reflective retaining wall 13, as much light as possible emitted by the light-emitting element 12 at the edge of the lamp board 1 can be reflected into the functional film layer 2 above the lamp board 1, and the direction of light reflection can be controlled so that it is emitted to the area in the backlight module where the light output brightness needs to be improved (such as Figure 1 the fourth area AA2 in), the design of the reflective retaining wall 13 will be specifically described below.

[0056] In the embodiment of the present utility model, as Figure 6 shown, in the direction perpendicular to the substrate 11 and pointing from the substrate 11 to the light-emitting element 12, the cross-sectional area of the reflective retaining wall 13 gradually decreases, that is, the arc surface of the reflective retaining wall 13 bends towards the side of the edge of the lamp board 1, so that the reflective retaining wall 13 forms a concave reflective surface on the side facing the light-emitting element 12, so that the incident angle of light incident on the arc surface is larger, and thus more light can be reflected to the functional film layer 2 above the lamp board 1, further improving the utilization rate of the light emitted by the lamp board 1.

[0057] The curved surface equation satisfied by the arc surface of the reflective retaining wall 13 can be obtained by integrating the tangent equations of each point on the arc surface.

[0058] Figure 7 It is the design schematic diagram of the arc surface of the reflective retaining wall provided by the embodiment of the present utility model.

[0059] As Figure 7 shown, taking the center point on the bottom surface of the light-emitting element 12 as the origin O(0, 0), taking the first direction X as the direction of the horizontal axis x of the rectangular coordinate system, and taking the direction perpendicular to the substrate 11 and pointing from the substrate 11 to the light-emitting element 12 as the direction of the vertical axis y of the rectangular coordinate system to establish a rectangular coordinate system.

[0060] The coordinates of any point P on the arc surface are (x, y), and the light i emitted by the light-emitting element 12 is incident on the P point on the arc surface. The slope of the light i is:

[0061]

[0062] The light ray i is reflected at point P on the arc surface, and the slope k of the reflected light ray r r is:

[0063]

[0064] where h and a are set values, and the values of h and a are determined by the boundary position of the display area AA and the position of the functional film layer 2. Refer to Figure 4 and Figure 5 , a part of the structure of the light-emitting element 12 in the row or column closest to the edge of the lamp board 1 is located in the non-display area AA', and the reflected light ray r needs to be incident on the edge of the display area AA at least. Refer to Figure 7 , h represents the ordinate at which the reflected light ray r is incident on the functional film layer 2, and a represents the spacing between the edge of the display area AA and the origin O(0, 0) in the horizontal axis direction.

[0065] According to the slopes of the incident light ray i and the reflected light ray r at point P, the slope k of the normal line n at point P on the arc surface can be calculated n :

[0066]

[0067] The slope of the tangent line t at point P on the arc surface is the reciprocal of the slope k of the normal line n, that is, k n is t = 1 / k n , k t satisfies the following relationship:

[0068]

[0069] In the above expression of k t , θ, h and a are all conditions preset during design. Therefore, k t is only an expression about x. By integrating x, the curve equation satisfied by the arc surface can be calculated:

[0070]

[0071] where x and y respectively represent the abscissa and ordinate of any point on the arc surface in the rectangular coordinate system, D1 and D2 respectively represent the minimum and maximum values of the abscissa of the points on the arc surface. For example, the value of D1 is -(L + d), the value of D2 is -L, and d is the width of the arc surface in the horizontal axis direction. Combining the boundary condition: the arc surface y = f(x) passes through point Q(-L, 0), that is, f(L) = 0, the expression of the equation satisfied by the arc surface can be calculated.

[0072] Based on the above design principle, by calculating and simulating a sufficient number of light rays, the specific surface shape of the arc surface in the reflective baffle 13 provided in the embodiment of the present invention can be calculated and modeled in optical design software. It can be understood that the selection of the origin position in the equation, the establishment method of the rectangular coordinate system, the value of the parameters, etc. can all be adjusted according to actual needs.

[0073] To make the improvement of the light efficiency of the backlight module provided by the embodiment of the present invention more intuitively visible, the embodiment of the present invention also performs simulation and testing on the light output situation of the backlight module.

[0074] Figure 8 It is a curve comparison diagram of the normalized brightness before and after setting the reflective baffle in the backlight module; Figure 9 It is a scatter diagram of the difference in normalized brightness before and after setting the reflective baffle in the backlight module.

[0075] Among them, Figure 8 It respectively shows the situation where the normalized brightness of the backlight module changes with the distance from the edge of the backlight module when the reflective baffle 13 is not set on the lamp board 1 and when the reflective baffle 13 is set on the lamp board 1. The abscissa represents the distance (unit: mm) between the test position and the center position of the backlight module in the first direction X, and the ordinate represents the normalized brightness value. Figure 9 And Figure 8 Correspondingly, it shows the difference in the normalized brightness of the backlight module when the reflective baffle 13 is set and not set on the lamp board 1 at the above test position. The abscissa represents the distance (unit: mm) between the test position and the center position of the backlight module in the first direction X, and the ordinate represents the increase in normalized brightness.

[0076] From Figure 8 and Figure 9 it can be seen that by setting the reflective baffle 13 with an arc surface on the lamp board 1, the brightness of a certain area inside and outside the display area AA can be increased simultaneously, and the brightening range can radiate to a certain area inward from the edge of the display area AA. For example, from Figure 8 and Figure 9 it can be known that after setting the reflective baffle 13, within a range of about 25 mm from the edge of the backlight module inward, the light output brightness can all have a certain increase. At the edge of the display area AA, the normalized brightness of the backlight module is increased from 45.2% to 53.5%, with an increase of 8%. It can be seen that by setting the reflective baffle 13 on the lamp board 1 in the embodiment of the present invention, the light output brightness of the backlight module in a certain area near the edge of the display area AA can be increased, which is beneficial to improving the problem that the light output brightness of the edge area of the backlight module is relatively low and enhancing the uniformity of the backlight.

[0077] The above is a specific description of the design and effect of the reflective baffle 13. Other structures in the backlight module can be designed according to specific requirements.

[0078] like Figure 6 As shown, the light emitting side of the light board 1 may include a plurality of stacked functional film layers 2 such as a diffuser plate / diffuser sheet 21, a uniform light film 22, a color conversion film 23, a brightening film 24, and a polarizing film 25. The functional film layer 2 has the function of modulating the light of the light board 1 and improving the brightness and uniformity of the light emitted by the backlight module.

[0079] Among them, the material used for the diffuser plate / diffuser film 21 can include at least one of polymethyl methacrylate (PMMA), polycarbonate (PC), polystyrene material (PS), and polypropylene (PP). The diffuser plate / diffuser film can be used to diffuse the angle of the light emitted by the light board 1 to increase the display viewing angle range.

[0080] The light-homogenizing film 22 includes a substrate and scattering particles coated on the substrate. The substrate can be made of polyethylene terephthalate (PET) or glass, etc. The scattering particles can be made of titanium dioxide, zinc oxide, calcium oxide, etc. The light incident on the scattering film can be reflected or refracted multiple times between the scattering particles and fully mixed, which is beneficial to improving the uniformity of the light output.

[0081] The color conversion film 23 can be made of one of the quantum dot film or the fluorescent film. The light incident on the color conversion film 23 can be used as excitation light to excite the quantum dot material or the fluorescent material to emit light of other colors. For example, the light-emitting element 12 emits blue light, and the blue light is incident on the color conversion film to excite red light and green light. The red light, green light and blue light are mixed into white backlight for emission.

[0082] The brightness enhancement film 24 may be, for example, a prism film (Brightness Enhancement Film, referred to as BEF), which has a plurality of prism structures extending in the same direction, and can be used to concentrate the light emitted from a large viewing angle to emit at a smaller viewing angle, thereby increasing the brightness of the light emitted within the normal viewing angle range. Usually, two pieces of brightness enhancement films 24 can be stacked and arranged, and the extending directions of the prism structures in the two pieces of brightness enhancement films 24 are orthogonal, thereby further improving the brightness of the light emitted.

[0083] The polarizer 25 can be, for example, a reflective polarizer (Dual-Brightness Enhance Film, abbreviated as DBEF), etc. The DBEF can be used to selectively transmit light of one polarization direction, such as P light, and reflect light with a polarization direction perpendicular thereto, such as S light. When the backlight module is applied to a display device, a polarizer and other structures are usually also provided in the display panel 200 of the display device. The light can be reflected multiple times and recycled between the backlight module 100 and the display panel 200, thereby improving the light output brightness.

[0084] In practical applications, the number, type, arrangement method, etc. of the functional film layers 2 in the backlight module can be designed according to requirements. For example, a wavelength selection layer can also be provided between the color conversion film 23 and the brightness enhancement film 24. The wavelength selection layer can allow light of a set wavelength to pass through while blocking light of other wavelength bands except the set wavelength, thereby improving the light output efficiency of the light of the set wavelength. For example, when the light-emitting element 12 emits blue light, the wavelength selection layer can adopt a blue light transmission film. The color conversion film 23 is disposed on the light output side of the blue light transmission film. The blue light transmission film has a good transmittance for blue light, so that the blue light can be incident on the color conversion film 23 to excite the wavelength conversion material to emit red light and green light, improving the light utilization rate. At the same time, the red light and green light can be reflected, thereby improving the light output efficiency of the red light, green light, and blue light and increasing the light output brightness of the white light formed by mixing the three. For another example, the number of the diffusion plate, diffusion sheet, and light homogenizing film can be multiple. For another example, when the light-emitting element 12 emits white light, the color conversion film 23 can be not provided in the backlight module. For another example, the BEF and the DBEF can be combined into an integral structure to reduce the thickness of the backlight module.

[0085] Based on the same inventive concept, an embodiment of the present invention further provides a display device. Figure 10 It is a cross-sectional view of the display device provided by the embodiment of the present invention.

[0086] As Figure 10 shown, the display device includes a backlight module 100 and a display panel 200 located on the light output side of the backlight module 100. The display panel 200 does not emit light by itself. The backlight module 100 provides backlight for the display panel 200, and the backlight forms a display image after being modulated by the display panel 200.

[0087] Exemplarily, the display panel 200 is a liquid crystal display panel. The display panel 200 may include an array substrate and a color filter substrate which are oppositely arranged. There is a liquid crystal layer between the array substrate and the color filter substrate. The control circuit in the array substrate can control the deflection direction of the liquid crystal molecules in the liquid crystal layer, modulate the transmittance and reflectance of the incident light, so as to change the brightness, contrast, etc. of the display picture. The light is converted into the required color by the color filter in the color filter substrate to form a color display picture. Polarizers may also be arranged on both sides of the display panel to improve the quality of the display picture. It can be understood that the specific composition of the display panel can be designed according to actual needs, and the embodiments of the present invention do not limit this here.

[0088] As Figure 10 shown, a light-shielding structure 3 is usually arranged near the edge of the display panel 200. The light-transmitting area within the light-shielding structure 3 is used as the display area AA. Referring to Figure 4 , Figure 5 and Figure 10 , at least part of the structure of the light-emitting element 12 near the edge of the lamp board 1 is located in the non-display area AA', that is, it is shielded by the light-shielding structure 3.

[0089] Since the light-shielding structure 3 shields part of the area of the backlight module 100, the size of the area that the light reflected by the light-reflecting retaining wall 13 needs to cover is reduced. For example, if there is no light-shielding structure 3 in the display device, the areas where the backlight module 100 needs to increase the brightness include Figure 2 the second area AA' and the fourth area AA2 shown in

[0090] 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 to include the preferred embodiments and all changes and modifications falling within the scope of the present invention.

[0091] 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 also intends to include these changes and modifications.

Claims

1. A light board, characterized in that, Comprising: a substrate, a plurality of light-emitting elements, and a light-reflecting retaining wall, the plurality of light-emitting elements and the light-reflecting retaining wall being located on the surface of the substrate; the light-reflecting retaining wall surrounds the plurality of light-emitting elements, and a side wall of the light-reflecting retaining wall facing the plurality of light-emitting elements has an arc-shaped surface, the light-reflecting retaining wall being configured to reflect light emitted by the light-emitting elements; wherein, in a direction perpendicular to the substrate and pointing from the substrate to the light-emitting elements, an area of a cross-section of the light-reflecting retaining wall gradually decreases; the arc-shaped surface satisfies the following equation: where x and y respectively represent the abscissa and ordinate of any point on the arc surface in the rectangular coordinate system, D1 and D2 respectively represent the minimum and maximum values of the abscissa of the points on the arc surface, k t represents the slope of the tangent line at the point with coordinates (x, y) on the arc surface, k t satisfies the following relationship: where θ represents an incident angle of light incident on a point with coordinates (x, y) on the arc-shaped surface, and h and a are set values.

2. The light board according to claim 1, wherein a height of the light-reflecting retaining wall is greater than or equal to a height of the light-emitting elements.

3. The light board according to claim 1, characterized in that, the plurality of light-emitting elements are arranged in an array in a first direction and a second direction, a spacing between the light-reflecting retaining wall and the closest light-emitting element in the first direction is less than a spacing between adjacent light-emitting elements in the first direction, and a spacing between the light-reflecting retaining wall and the closest light-emitting element in the second direction is less than a spacing between adjacent light-emitting elements in the second direction.

4. The light board according to any one of claims 1 to 3, characterized in that a material of the light-reflecting retaining wall includes one of polycarbonate doped with titanium dioxide, silver, or organosilica gel doped with titanium dioxide.

5. The light board according to claim 4, characterized in that, a reflectivity of the light-reflecting retaining wall is 80% - 100%.

6. A backlight module, characterized in that, Comprising a light board according to any one of claims 1 - 5 and a plurality of functional film layers, the plurality of functional film layers being located on a light-emitting side of the light board and configured to modulate light emitted by the light board.

7. The backlight module according to claim 6, wherein, the light-reflecting retaining wall in the light board is in contact with the functional film layer.

8. A display device, characterized in that, Comprising a backlight module according to claim 6 or 7 and a display panel, the display panel being located on a light-emitting side of the backlight module.

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