Backlight module

Abstract

The utility model provides a backlight module. The backlight module comprises a light source structure, the light source structure comprises a circuit board and a plurality of light sources, and the light sources are arranged on the circuit board in an array mode; each light source is covered with the corresponding light reflecting cover, a filling structure is arranged in at least part of each light reflecting cover, each filling structure is provided with a fully reflecting surface, and the fully reflecting surfaces are arranged opposite to the light sources and used for totally reflecting light emitted by the light sources; the diffusion layer is located on the side, away from the light source, of the reflecting cover, and the diffusion layer comprises a microlens array layer; the color conversion layer is located on the side, away from the light source, of the diffusion layer, and the color conversion layer is used for changing the color of the emergent light. The backlight module solves the problem that the brightness of light spots of a backlight module in the prior art is not uniform.

Description

Technical Field

[0001] The utility model relates to the technical field of optical display equipment, in particular to a backlight module. Background Art

[0002] Usually, a liquid crystal display device is provided with a backlight module on the back of the liquid crystal panel as a light source for illuminating the liquid crystal panel. In the current backlight module, an array of micro-light-emitting diodes (micro LEDs) is usually used as a light source structure. With the development of thin and light televisions, the mixing distance of the backlight module is getting smaller and smaller, that is, the thickness of the air layer between the light source structure and the diffuser is getting smaller and smaller. Insufficient light mixing can easily cause most of the light emitted by the LED to be concentrated in the center of the beam and the beam angle that deviates from the center in a small range. This part of highly concentrated light will produce a higher light intensity, so that a small and bright light spot will be formed directly above the position of the lamp when projected onto the panel, making the brightness more concentrated and the uniformity poor. If the arrangement spacing of the LED chips in the light source structure is reduced in order to improve uniformity, and the diffuser is thickened in the form of superimposing multiple diffusers, the light concentration will be reduced, but such a setting will increase the thickness of the entire backlight module, which is not conducive to achieving the thinness of the backlight module.

[0003] That is to say, the backlight module in the prior art has the problem of uneven brightness of the light spot. Utility Model Content

[0004] The main purpose of the utility model is to provide a backlight module to solve the problem of uneven brightness of light spots in the backlight module in the prior art.

[0005] In order to achieve the above-mentioned purpose, the utility model provides a backlight module, including: a light source structure, the light source structure includes a circuit board and a plurality of light sources, the plurality of light sources are arrayed on the circuit board; a reflector, there are a plurality of reflectors, each light source is covered with a reflector, at least part of the reflectors are provided with a filling structure, the filling structure has a total reflection surface, the total reflection surface is arranged opposite to the light source, the total reflection surface is used for total reflection of light emitted by the light source; a diffusion layer, the diffusion layer is located on a side of the reflector away from the light source, the diffusion layer includes a microlens array layer; a color conversion layer, the color conversion layer is located on a side of the diffusion layer away from the light source, the color conversion layer is used for changing the color of the emitted light.

[0006] Furthermore, the distance from the surface of the filling structure on the side away from the light source to the light source is equal to the distance from the side of the reflector on the side away from the light source to the light source, and the surface of the filling structure on the side away from the light source has a groove, the groove wall of the groove is a total reflection surface, and the projection area of ​​the total reflection surface on the light source is smaller than the projection area of ​​the filling structure on the light source.

[0007] Furthermore, the groove is a conical groove, the apex of the conical groove is on the center line of the light source; and / or the cross section of the groove along the direction perpendicular to the light source is V-shaped.

[0008] Furthermore, a ratio between the depth of the groove and the notch width of the groove is greater than or equal to 1 / 2 and less than or equal to 3.

[0009] Furthermore, the reflector has a first opening and a second opening that are arranged opposite to each other, the size of the second opening is larger than that of the first opening, the light source is located at the first opening, and the ratio of the size of the second opening to the distance from the second opening to the light source is greater than or equal to 1 and less than or equal to 7.

[0010] Furthermore, the inner wall surface of the reflector is a curved surface, and the cross-sectional area of ​​at least part of the reflector in the direction parallel to the light source gradually increases from the light incident side to the light exiting side; and / or multiple reflectors are arranged in an array, and multiple reflectors located in the outer circle of the multiple reflectors arranged in the array are of a non-axisymmetric structure, and the multiple reflectors of the non-axisymmetric structure are divided into a first part and a second part by a surface formed by extending the center line of the light source, and the second part is arranged at a position away from the center of the light source structure relative to the first part, and the second part includes a first arc segment and a second arc segment connected at an angle from the light incident side to the light exiting side.

[0011] Furthermore, both side surfaces of the diffusion layer have multiple microstructures, and the multiple microstructures on the light output side of the diffusion layer are all microlenses. The multiple microlenses are arranged in an array to form a microlens array layer, and the refractive index of the microlens array layer is greater than or equal to 1 and less than or equal to 5.

[0012] Furthermore, the multiple microstructures on the light incident side of the diffusion layer are all conical grooves.

[0013] Furthermore, the filling structure is a glue structure, and the refractive index of the glue structure is greater than or equal to 1 and less than or equal to 5.

[0014] Furthermore, the color conversion layer includes one of a quantum dot film layer and a fluorescent film layer; and / or the light source is a MiniLED light source, and the diameter of the MiniLED light source is greater than or equal to 50 microns and less than or equal to 200 microns.

[0015] According to the technical solution of the utility model, the backlight module includes a light source structure, a reflector, a diffusion layer and a color conversion layer. The light source structure includes a circuit board and a plurality of light sources, and the plurality of light sources are mounted on the circuit board in an array. There are a plurality of reflectors, each light source is covered with a reflector, and at least part of the reflectors is provided with a filling structure, the filling structure has a total reflection surface, the total reflection surface is arranged opposite to the light source, and the total reflection surface is used for total reflection of light emitted by the light source. The diffusion layer is located on a side of the reflector away from the light source, and the diffusion layer includes a microlens array layer. The color conversion layer is located on a side of the diffusion layer away from the light source, and the color conversion layer is used for changing the color of the emitted light.

[0016] By providing a reflector on each light source, multiple light sources and multiple reflectors are arranged one-to-one, so that the edge light of the light source can be smoothly emitted after being reflected by the reflector, which can reduce light loss, increase the utilization rate of the light source light, and help improve the brightness of the emitted light spot. At least part of the reflector is provided with a filling structure, the filling structure has a total reflection surface, the total reflection surface is arranged opposite to the light source, and the total reflection surface is used to fully reflect the light emitted by the light source. This arrangement not only allows the filling structure to protect the light source, but also allows the central light emitted by the light source to be received by the total reflection surface and fully reflected to the reflector, and then emitted, so that the total reflection surface can disperse the light emitted by the light source. The central light is relatively concentrated, thereby reducing the central brightness. In addition, the diffusion layer including the microlens array layer cooperates with the filling structure to suppress the central bright spot, improve the edge brightness, make the distribution of the emitted light more uniform, and improve the uniformity of the brightness of the emitted light spot. By providing a color conversion layer, the color conversion layer plays a role in changing the color of the emitted light to obtain light of the desired color. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings constituting part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings:

[0018] Figure 1 A schematic structural diagram of a backlight module of an optional embodiment of the utility model is shown;

[0019] Figure 2 Shows Figure 1 A schematic diagram of the assembly of the light source structure and the reflector of the backlight module;

[0020] Figure 3 A partial schematic diagram of a backlight module of an optional embodiment of the utility model is shown;

[0021] Figure 4 Shows Figure 1 A top view of a backlight module;

[0022] Figure 5 Shows Figure 1 A schematic diagram of the structure of the diffusion layer of the backlight module;

[0023] Figure 6 Shows Figure 5 Schematic diagram of the light path of the diffusion layer in FIG.

[0024] Figure 7 Shows Figure 5 Schematic diagram of the light path of the diffusion layer in .

[0025] The above drawings include the following reference numerals:

[0026] 10. Light source structure; 11. Circuit board; 12. Light source; 13. Center line; 20. Reflector; 21. First part; 22. Second part; 221. First arc segment; 222. Second arc segment; 23. First opening; 24. Second opening; 30. Filling structure; 31. Total reflection surface; 32. Transmission area; 41. First diffusion layer; 411. Conical groove; 42. Base; 43. Second diffusion layer; 431. Microlens; 50. Color conversion layer. DETAILED DESCRIPTION

[0027] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present utility model will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0028] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meanings as commonly understood by ordinary technicians in the technical field to which this application belongs.

[0029] In the present invention, unless otherwise specified, the directional words used, such as "up, down, top, bottom", usually refer to the directions shown in the drawings, or to the components themselves in the vertical, perpendicular or gravity directions; similarly, for ease of understanding and description, "inside and outside" refer to the inside and outside relative to the outline of each component itself, but the above-mentioned directional words are not used to limit the present invention.

[0030] In order to solve the problem of uneven brightness of light spots in the backlight module in the prior art, the utility model provides a backlight module.

[0031] like Figures 1 to 7 As shown, the backlight module includes a light source structure, a reflector, a diffusion layer and a color conversion layer. The light source structure includes a circuit board 11 and multiple light sources 12. The multiple light sources 12 are mounted on the circuit board 11 in an array; there are multiple reflectors 20, each light source 12 is covered with a reflector 20, at least part of the reflectors 20 is provided with a filling structure 30, the filling structure 30 has a total reflection surface 31, the total reflection surface 31 is arranged opposite to the light source 12, and the total reflection surface 31 is used to fully reflect the light emitted by the light source 12; the diffusion layer is located on the side of the reflector 20 away from the light source 12, and the diffusion layer includes a microlens array layer; the color conversion layer 50 is located on the side of the diffusion layer away from the light source 12, and the color conversion layer 50 is used to change the color of the emitted light.

[0032] By providing a reflector 20 on each light source 12, multiple light sources 12 and multiple reflectors 20 are arranged in a one-to-one correspondence, so that the edge light of the light source 12 can be smoothly emitted after being reflected by the reflector 20, which can reduce light loss, increase the utilization rate of the light of the light source 12, and help improve the brightness of the emitted light spot. At least part of the reflector 20 is provided with a filling structure 30, and the filling structure 30 has a total reflection surface 31, which is arranged opposite to the light source 12, and the total reflection surface 31 is used to fully reflect the light emitted by the light source 12. This arrangement not only allows the filling structure 30 to protect the light source 12, but also allows the central light emitted by the light source 12 to be received by the total reflection surface 31 and fully reflected to the reflector, and then emitted, so that the total reflection surface 31 can disperse the relatively concentrated central light emitted by the light source 12, thereby reducing the central brightness. In addition, the diffusion layer including the microlens array layer cooperates with the filling structure 30 to suppress the central bright spot, increase the edge brightness, make the outgoing light distribution more uniform, and improve the uniformity of the brightness of the outgoing light spot. By setting the color conversion layer 50, the color conversion layer 50 plays a role in changing the color of the outgoing light to obtain the desired color of light.

[0033] like Figure 1 and Figure 2 As shown, the light source 12 is a Mini LED light source, and the diameter of the Mini LED light source is greater than or equal to 50 microns and less than or equal to 200 microns. In a specific embodiment of the present application, the light source structure 10 emits blue light, which can excite red light and green light through the quantum dot film layer, and mix with the emitted blue light to form high-quality white light. The white light obtained in this way has a purer chromaticity, a higher color gamut coverage, and a stable performance of the quantum dot film layer, which can ensure that the color remains unchanged for a long time. The color gamut of the display is greatly improved to ensure that the displayed colors are more vivid and dynamic.

[0034] It should also be noted that the multiple light sources 12 are mounted in an array on the circuit board 11, and the multiple light sources 12 are arranged in a one-to-one correspondence with the multiple reflectors 20, so that the light spots formed by the light emitted by the multiple light sources 12 have an array form, so that the output light is arranged in the same way, and uneven output due to non-array will not occur.

[0035] like Figure 3 and Figure 4As shown, the internal space of the reflector 20 is completely filled with the filling structure 30, and the distance from the side surface of the filling structure 30 away from the light source 12 to the light source 12 is equal to the distance from the side surface of the reflector 20 away from the light source 12 to the light source 12. Specifically, the transmission area 32 of the side surface of the filling structure 30 away from the light source 12 is flush with the light outlet of the reflector 20, and the side surface of the filling structure 30 away from the light source 12 has a groove, which corresponds to the light source 12, and the groove wall surface of the groove is a total reflection surface 31, and the projection area of ​​the total reflection surface 31 on the light source 12 is smaller than the projection area of ​​the filling structure 30 on the light source 12, and the projection of the total reflection surface 31 on the light source 12 completely covers the light source 12. This is equivalent to digging a groove in the central area of ​​the side surface of the filling structure 30 away from the light source 12 to form the groove. This arrangement enables the total reflection surface 31 to be formed by the groove wall surface of the groove, which is beneficial for the total reflection surface 31 to totally reflect the central light emitted by the light source 12 to the edge and then emit it into the reflector. The surface of the side of the filling structure 30 away from the light source 12 is the transmission area 32 except the area where the groove is located. The reflected light of the reflector is emitted from the transmission area 32. This arrangement enables the total reflection surface 31 to receive the central light of the light source 12 and reflect it to the reflector 20, thereby ensuring the stability of light transmission and increasing the angle of the emitted light. Figure 3 The light path after two reflections is shown, and the actual light path will have more reflections. The filling structure 30 can filter small angle light and increase the light mixing distance, so that the central energy is diffused to the surroundings, so that the light energy is distributed to a larger area and the energy is evenly distributed.

[0036] Specifically, the groove is a conical groove, and the apex of the conical groove is on the center line 13 of the light source 12. The conical groove can be a conical groove or a polygonal pyramid groove. The cross section of the groove along the direction perpendicular to the light source 12 is V-shaped. The ratio between the depth of the groove and the width of the groove is greater than or equal to 1 / 2 and less than or equal to 3. By rationally planning the shape and size of the groove, it is helpful to ensure the reliability of the total reflection surface 31. Since the light emitted by the light source 12 is similar to the Lambertian distribution, that is, the center brightness is high and the edge brightness is low, the inner wall surface of the groove with a V-shaped cross section can fully reflect the small-angle light, filter the small-angle light, allow the large-angle light to emerge, and lower the center brightness. The small-angle light after total reflection is reflected by the reflector 20, and the small-angle light is filtered again when it emerges, so that it is fully reflected, thereby increasing the mixed light distance and increasing the uniformity of the emergent light.

[0037] like Figure 2As shown, the reflector 20 has a first opening 23 and a second opening 24 arranged opposite to each other, the size of the second opening 24 is larger than the size of the first opening 23, specifically, the width of the second opening 24 in a direction parallel to the light source 12 is larger than the width of the first opening 23 in a direction parallel to the light source 12, the light source 12 is located at the first opening 23, specifically, the light source 12 enters the reflector 20 from the first opening 23, so that the light source 12 is arranged inside the reflector 20, and the center line 13 of the light source 12 coincides with the center axis of the reflector 20, the side of the reflector 20 having the first opening 23 is connected to the circuit board 11, and the second opening 24 is located on the light-emitting side. The ratio of the size of the second opening 24 to the distance from the second opening 24 to the light source 12 is greater than or equal to 1 and less than or equal to 7, specifically, the ratio of the width of the second opening 24 to the distance from the second opening 24 to the light source 12 is greater than or equal to 1 and less than or equal to 7. This arrangement enables the present application to use the reflector 20 to reflect and reuse the light emitted at a large angle, which can increase the brightness and reduce the light loss.

[0038] In an optional embodiment of the present application, the reflector 20 is in a cone shape, specifically, the reflector 20 is in a cone shape or a quadrangular pyramid shape.

[0039] Specifically, the inner wall surface of the reflector 20 is a curved surface, and the cross-sectional area of ​​at least part of the reflector 20 in the direction parallel to the light source 12 gradually increases from the light incident side to the light exit side. The multiple reflectors 20 are arranged in an array, and the multiple reflectors 20 located in the outermost circle of the multiple reflectors 20 arranged in the array are non-axisymmetric structures. Specifically, the multiple light sources 12 are arranged in a rectangular array, so the multiple reflectors 20 are also arranged in a rectangular array, and the multiple reflectors 20 in the outermost circle of the multiple reflectors 20 arranged in the rectangular array are non-axisymmetric structures, and the remaining reflectors 20 are axisymmetric structures. The multiple reflectors 20 with non-axisymmetric structures are divided into a first part 21 and a second part 22 by a surface extending from the center line 13 of the light source 12. The second part 22 is arranged away from the center position of the light source structure 10 relative to the first part 21. The second part 22 includes a first arc segment 221 and a second arc segment 222 connected at an angle from the light incident side to the light emitting side, and the height of the second arc segment 222 is greater than the height of the first arc segment 221.

[0040] refer to Figure 2As shown, the second part 22 of the outermost circle of the reflector 20 is equivalent to expanding a part outward near the light-emitting side to form a second arc segment 222. The second arc segment 222 extends to the second opening 24 of the reflector 20, and the vertical distance from the side of the second arc segment 222 close to the light source 12 to the center line 13 of the light source 12 is smaller than the vertical distance from the side of the second arc segment 222 away from the light source 12 to the center line 13 of the light source 12, and the vertical distance from the side of the second arc segment 222 away from the light source 12 to the center line 13 of the light source 12 is greater than the vertical distance from the side of the first part 21 away from the light source 12 to the center line 13 of the light source 12. A reflective film is provided on the inner wall surface of the reflector 20. By providing the second arc segment 222, light can be better reflected, reducing the loss in the light reflection process.

[0041] like Figures 5 to 7 As shown, both sides of the diffusion layer have multiple microstructures, and the multiple microstructures on the light-emitting side of the diffusion layer are all microlenses 431. The multiple microlenses 431 are arranged in an array to form the above-mentioned microlens array layer, and the refractive index of the microlens array layer is greater than or equal to 1 and less than or equal to 5. By providing the microlens array layer, the energy of the center point of the light can be reduced after the light passes through the diffusion layer, the light diffusion area is increased, and the light uniformity is improved.

[0042] Specifically, the multiple microstructures on the light incident side of the diffusion layer are all conical grooves 411. Specifically, the diffusion layer includes a substrate 42, a first diffusion layer 41 arranged on the light incident side of the substrate 42, and a second diffusion layer 43 arranged on the light exit side of the substrate 42, and the substrate 42 is optical glass or optical plastic. The second diffusion layer 43 is a microlens array layer, and the first diffusion layer 41 is equivalent to a layer structure in which multiple conical grooves 411 are dug. The conical groove 411 is specifically a polygonal pyramid groove, preferably a quadrangular pyramid groove. The cross-sectional shape of the conical groove 411 along the direction perpendicular to the light source 12 is V-shaped. Since the light emitted by the light source 12 is approximately Lambertian in distribution, that is, the center brightness is high and the edge brightness is low, although the small-angle light can be filtered after passing through the conical groove 411 or the microlens 431, there may still be a bright spot in the center. By setting the diffusion layer to a double-sided structure and planning the light incident side to be a conical groove 411, the light is emitted from the air into the conical groove 411, referring to Figure 6 The small-angle light emitted by the light source 12 diffuses to the surroundings when incident on the conical groove 411, reducing the energy at the center point, increasing the light diffusion area, and distributing the light energy to a larger area, thereby improving the uniformity of energy distribution. Then, the light is incident on the microlens 431, and after diffusion by the microlens 431, a light spot with a larger area and more uniform brightness can be formed.

[0043] Further, refer to Figure 7In order to make the brightness of the emitted light spot more uniform, it is necessary to diffuse the energy of the middle light spot to the surroundings, distribute the light energy to a larger area, and make the light more uniform. The upper microlens array layer can diffuse the light passing through the substrate 42 at a larger angle. A beam of light from the light source 12 is dispersed after passing through the first diffusion layer 41. The dispersed light rays are superimposed on each other, making the output light more uniform. After the light enters the microlens array layer, a variety of light paths occur. Part of the light enters the microlens array layer and does not meet the total reflection condition. It is directly emitted from the microlens array layer. The emitted light is deflected to both sides, reducing the brightness of the center of the light. After another part of the light enters the microlens array layer, it meets the total reflection condition and undergoes total reflection. The reflected light enters the first diffusion layer 41 after passing through the substrate 42. At this time, the total reflection condition is not met in the first diffusion layer 41, and it is emitted through the conical groove 411. The light emitted through the conical groove 411 re-enters the reflector 20 and is reflected again, and then re-passes through the first diffusion layer 41, and the above-mentioned light path occurs again, and then it is emitted after passing through the substrate 42 and the microlens array layer. Since the light entering the diffusion layer is re-reflected into the reflector 20, the light rays are superimposed on each other and have a sufficient distance for light mixing, which increases the uniformity of the emitted light. Another part of the light enters the microlens array layer, meets the total reflection condition, and undergoes total reflection. The reflected light enters the first diffusion layer 41 after passing through the substrate 42, and then undergoes total reflection again, that is, the light rays are reflected multiple times inside the substrate 42 and the first diffusion layer 41, and finally pass through the microlens array layer to be emitted. After passing through the diffusion layer, the light rays are superimposed on each other and have a sufficient distance for light mixing, which increases the brightness uniformity of the emitted light.

[0044] It should be noted that the above-mentioned multiple micro lenses 431 include one or more of convex lenses and concave lenses, which can be set according to actual conditions.

[0045] It should also be noted that the multiple conical grooves 411 on the light-incoming side of the diffusion layer are randomly arranged. The multiple microlenses 431 on the light-outgoing side of the diffusion layer are randomly distributed in the center position of the curved surface, the size of the curved surface, and the Z-axis height. This arrangement is conducive to eliminating diffraction fringes.

[0046] Specifically, the filling structure 30 is a glue structure, specifically a transparent glue structure. The refractive index of the glue structure is greater than or equal to 1 and less than or equal to 5. By reasonably constraining the refractive index of the glue structure, it is helpful to ensure the refraction transmission of light therein. Since the refractive index is greater than that of air, the glue structure can fully reflect or diffuse small-angle light. The microlens array layer can also diffuse light because its refractive index is greater than that of air, so that light energy is distributed to a larger area and the energy is evenly distributed.

[0047] like Figure 1As shown, the color conversion layer 50 includes one of a quantum dot film layer and a fluorescent film layer. The quantum dot film layer is used to convert the blue light emitted by the light source 12 into white light. Scattering particles, green quantum dots and red quantum dots are dispersed in the quantum dot film layer. The scattering particles scatter the incident blue light so that the green quantum dots and the red quantum dots are more fully excited to stimulate green light and red light of a specific band. The green light and the red light are mixed with the transmitted blue light to form white light, and the color gamut coverage is high. The fluorescent film layer is used to convert the blue light emitted by the incident light source 12 into white light. The fluorescent film layer is dispersed with fluorescent powder, and the fluorescent powder generates white light when excited by blue light. By reasonably setting the color conversion layer 50, the light diffused through the diffusion layer can form a uniform white light through the color conversion layer 50.

[0048] In summary, the present application provides a direct-down backlight module, which reduces the energy of the center point and diffuses the light through a microlens array layer. There is no need to use multiple light-homogenizing films for light homogenization like traditional Mini LED backlight modules, and a reflector 20 is provided to reuse the light emitted laterally from the light source 12. While reducing the thickness of the diffusion layer, the reflector 20 and the filling structure 30 therein are used to increase the brightness of the backlight module, reducing the thickness of the backlight module, so that the backlight module of the present application has the advantages of being light and thin, and having uniform brightness of the output light spot.

[0049] Obviously, the embodiments described above are only some embodiments of the utility model, not all embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the utility model.

[0050] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0051] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein.

[0052] The above description is only the preferred embodiment of the utility model, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A backlight module, characterized in that: include: A light source structure (10), the light source structure (10) comprising a circuit board (11) and a plurality of light sources (12), the plurality of light sources (12) being mounted on the circuit board (11) in an array; A reflector (20), wherein there are a plurality of reflectors (20), each of the light sources (12) is covered with the reflector (20), at least some of the reflectors (20) are provided with a filling structure (30), the filling structure (30) has a total reflection surface (31), the total reflection surface (31) is arranged opposite to the light source (12), and the total reflection surface (31) is used to totally reflect light emitted by the light source (12); a diffusion layer, the diffusion layer being located on a side of the reflector (20) away from the light source (12), the diffusion layer comprising a microlens array layer; A color conversion layer (50) is located on a side of the diffusion layer away from the light source (12), and the color conversion layer (50) is used to change the color of the emitted light.

2. The backlight module according to claim 1, characterized in that: The distance between the surface of the side of the filling structure (30) away from the light source (12) and the light source (12) is equal to the distance between the side of the reflector (20) away from the light source (12) and the light source (12); a groove is provided on the surface of the side of the filling structure (30) away from the light source (12); the groove wall surface of the groove is the total reflection surface (31); and the projection area of ​​the total reflection surface (31) on the light source (12) is smaller than the projection area of ​​the filling structure (30) on the light source (12).

3. The backlight module according to claim 2, characterized in that: The groove is a conical groove, the apex of which is on the center line (13) of the light source (12); and / or the cross section of the groove along a direction perpendicular to the light source (12) is V-shaped.

4. The backlight module according to claim 2, characterized in that: The ratio of the depth of the groove to the notch width of the groove is greater than or equal to 1 / 2 and less than or equal to 3.

5. The backlight module according to claim 1, characterized in that: The reflector (20) comprises a first opening (23) and a second opening (24) which are arranged opposite to each other, the size of the second opening (24) is larger than the size of the first opening (23), the light source (12) is located at the first opening (23), and the ratio of the size of the second opening (24) to the distance from the second opening (24) to the light source (12) is greater than or equal to 1 and less than or equal to 7.

6. The backlight module according to claim 1, characterized in that: The inner wall surface of the reflector (20) is a curved surface, and the cross-sectional area of ​​at least a portion of the reflector (20) in a direction parallel to the light source (12) gradually increases from the light incident side to the light exit side; and / or The plurality of reflectors (20) are arranged in an array, and the plurality of reflectors (20) located in an outer circle of the plurality of reflectors (20) arranged in an array are of a non-axisymmetric structure. The surface formed by the extension of the center line (13) of the light source (12) of the plurality of reflectors (20) of the non-axisymmetric structure is divided into a first part (21) and a second part (22). The second part (22) is arranged away from the center position of the light source structure (10) relative to the first part (21), and the second part (22) comprises a first arc segment (221) and a second arc segment (222) connected at an angle from the light incident side to the light exit side.

7. The backlight module according to claim 1, characterized in that: Both side surfaces of the diffusion layer have a plurality of microstructures, the plurality of microstructures on the light-emitting side of the diffusion layer are all microlenses (431), the plurality of microlenses (431) are arranged in an array to form the microlens array layer, and the refractive index of the microlens array layer is greater than or equal to 1 and less than or equal to 5.

8. The backlight module according to claim 7, characterized in that: The multiple microstructures on the light incident side of the diffusion layer are all conical grooves (411).

9. The backlight module according to any one of claims 1 to 8, characterized in that: The filling structure (30) is a glue structure, and the refractive index of the glue structure is greater than or equal to 1 and less than or equal to 5.

10. The backlight module according to any one of claims 1 to 8, characterized in that: The color conversion layer (50) comprises one of a quantum dot film layer and a fluorescent film layer; and / or The light source (12) is a Mini LED light source, and the diameter of the Mini LED light source is greater than or equal to 50 micrometers and less than or equal to 200 micrometers.

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