Backlight module and display device

Abstract

The embodiment of the invention provides a backlight module and a display device. The backlight module comprises a transparent substrate, a light conversion layer, a plurality of light-emitting light sources and a second reflecting layer. A plurality of grooves are formed in one side of the transparent substrate, the side wall of the transparent substrate is arranged in a step mode, at least one first reflecting layer is arranged on each step, and the orthographic projection area of the first reflecting layer of the same step on the transparent substrate is smaller than that of the bottom of the step on the transparent substrate. The light conversion layer is filled in the groove. The light-emitting source is located on the side, away from the transparent substrate, of the light conversion layer. The orthographic projection of the light-emitting source on the transparent substrate and the orthographic projection of the light conversion layer on the transparent substrate are at least partially overlapped. The second reflecting layer is arranged on one side of the transparent substrate and is arranged on the same side as the light conversion layer, and the orthographic projection of the second reflecting layer on the substrate is not overlapped with the orthographic projection of the light conversion layer on the transparent substrate.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to a backlight module and a display device. Background Art

[0002] With the development of society, various display devices such as mobile phones, computers and televisions are becoming more and more inseparable from people's lives and work. Display devices generally include display panels and backlight modules. The backlight module provides light sources for the display panels, so that the display devices can display images normally.

[0003] While pursuing the display quality of display devices, higher requirements are also placed on the thinness of display devices. As a part of the display device, the thickness of the backlight module seriously restricts the overall thickness of the display device. Therefore, on the basis of meeting the brightness uniformity, a backlight module with a simple structure and thin thickness is urgently needed. Summary of the invention

[0004] The purpose of the embodiments of the present invention is to provide a backlight module and a display device to solve the problem that the existing backlight module has a complex structure and a relatively thick thickness. The specific technical solution is as follows:

[0005] The first aspect of the present application provides a backlight module, which includes: a transparent substrate, a plurality of grooves are provided on one side of the transparent substrate, the side walls of the grooves are arranged in a step-like manner, at least one first reflective layer is provided on each step, and the orthographic projection area of ​​the first reflective layer of the same step on the transparent substrate is smaller than the orthographic projection area of ​​the groove where the step is located on the transparent substrate; a light conversion layer, the light conversion layer is filled in the groove; a plurality of light emitting sources, the light emitting sources are located on the side of the light conversion layer away from the transparent substrate, and the orthographic projection of the light emitting source on the transparent substrate at least partially overlaps with the orthographic projection of the light conversion layer on the transparent substrate. A second reflective layer, the second reflective layer is arranged on one side of the transparent substrate between adjacent grooves, and is arranged on the same side as the groove.

[0006] In addition, the backlight module provided in the first aspect of the present application may also have the following technical features:

[0007] In some embodiments, the cross-sectional area of ​​the groove increases successively along a direction approaching the opening of the groove; and the orthographic projections of the first reflective layer of each level of steps on the transparent substrate do not overlap.

[0008] In some embodiments, the inner edge of the first reflective layer at the bottom of a step away from the bottom of the groove has an orthographic projection on the transparent substrate flush with the outer edge of the first reflective layer at the next step.

[0009] In some embodiments, the first reflective layer at the bottom of the groove is provided with a central position of the bottom of the groove.

[0010] In some embodiments, the sidewall of the groove includes at least two steps.

[0011] In some embodiments, a continuous protrusion structure or a discontinuous protrusion structure is provided on one side of the transparent substrate, and the second reflective layer is provided on the side of the continuous protrusion structure or the discontinuous protrusion structure away from the transparent substrate, and the orthographic projection of the continuous protrusion structure or the discontinuous protrusion structure on the transparent substrate overlaps with the orthographic projection of the second reflective layer on the transparent substrate.

[0012] In some embodiments, the first reflective layer exceeds the step by a distance of 0 μm-100 μm, and the second reflective layer covers the openings of the grooves on two adjacent sides by a length of 0 μm-100 μm.

[0013] In some embodiments, the light conversion layer is a quantum dot conversion layer or a fluorescent color conversion layer, and the first reflective layer and the second reflective layer are single reflective layers or composite reflective layers.

[0014] In some embodiments, the portion where the orthographic projection of the light source on the transparent substrate overlaps with the orthographic projection of the light conversion layer on the transparent substrate is a light emitting area, and the portion where the orthographic projection of the light source on the transparent substrate does not overlap with the orthographic projection of the light conversion layer on the transparent substrate is a pad area, and the pad area is electrically connected to an external circuit.

[0015] In some embodiments, the backlight module also includes a first packaging layer arranged on the side of the second reflective layer and the light conversion layer away from the transparent substrate; a second packaging layer is provided on the side of the light source away from the transparent substrate, and the second packaging layer is used to independently encapsulate each of the light sources.

[0016] In some embodiments, the second encapsulation layer is a white oil layer.

[0017] In some embodiments, the backlight module further includes a grating polarizer, and the grating polarizer is disposed on a side of the transparent substrate facing away from the second reflective layer and the light conversion layer.

[0018] A second aspect of the present application provides a display device, which includes the backlight module described above.

[0019] Beneficial effects of the embodiments of the present invention:

[0020] The backlight module provided by the embodiment of the present invention has a light conversion layer arranged in a stepped groove, so that the light conversion layer does not occupy additional space, which is conducive to reducing the thickness of the backlight module. The first reflection layer arranged at each step can transmit the light irradiated by the light source to the first reflection layer through multiple reflections from the other side of the transparent substrate, and the multiple transmissions allow the transmitted light to be transmitted in all directions, covering a wider area, thereby achieving a uniform light output effect and improving the light output uniformity of the backlight module. The second reflection layer is used to reflect the light reflected by the light conversion layer, so that the light is transmitted from the side of the transparent substrate facing away from the second reflection layer, thereby improving the light output efficiency.

[0021] Of course, it is not necessary to achieve all of the advantages described above at the same time to implement any product or method of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other embodiments can also be obtained based on these drawings.

[0023] Figure 1 A schematic diagram of the structure of a backlight module provided in an embodiment of the present application;

[0024] Figure 2 for Figure 1 Schematic diagram of the light propagation path of the light source of the backlight module without the grating polarizer;

[0025] Figure 3 A schematic diagram of the structure of a backlight module provided in an embodiment of the present application in another embodiment;

[0026] Figure 4-Figure 13 This is a schematic diagram of the manufacturing steps of the backlight module provided in an embodiment of the present application, wherein the backlight module does not include a grating polarizer.

[0027] The figure numbers are as follows: transparent substrate 10; groove 11; first reflective layer 12; second reflective layer 13; protruding structure 14; photoresist 15; etched hole 16; light conversion layer 20; light emitting light source 30; light emitting area 31; pad area 32; first lead 321; second lead 322; first metal trace 323; second metal trace 324; first packaging layer 40; second packaging layer 50; grating polarizer 60; distance L1; length L2. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field based on this application belong to the scope of protection of the present invention.

[0029] A first aspect of the present application provides a backlight module, such as Figure 1 , Figure 2 As shown, Figure 1 It is a schematic diagram of the structure of the backlight module. Figure 2 for Figure 1 Schematic diagram of the light propagation path of the light source 30 after removing the grating polarizer 60 from the backlight module, the backlight module includes: a transparent substrate 10, a light conversion layer 20, a plurality of light sources 30 and a second reflective layer 13. A plurality of grooves 11 are provided on one side of the transparent substrate 10 (wherein, Figure 1 , Figure 2 The portion filled by the light conversion layer 20 is the location of the groove 11), the side wall of the groove 11 is arranged in a step-like manner, and at least one first reflection layer 12 is arranged on each step. The orthographic projection area of ​​the first reflection layer 12 on the same step on the transparent substrate 10 is smaller than the orthographic projection area of ​​the groove 11 where the step is located on the transparent substrate 10. The light conversion layer 20 is filled in the groove 11. A plurality of light sources 30 are located on the side of the light conversion layer 20 away from the transparent substrate 10, and the orthographic projection of the light source 30 on the transparent substrate 10 at least partially overlaps with the orthographic projection of the light conversion layer 20 on the transparent substrate 10. The second reflection layer 13 is arranged on one side of the transparent substrate 10 between adjacent grooves 11, and is arranged on the same side as the groove 11.

[0030] In the embodiment of the present application, the light conversion layer 20 is arranged in the groove 11 of the transparent substrate 10, so the light conversion layer 20 does not need to occupy additional space, which can reduce the thickness of the backlight module. The first reflective layer 12 set at each step can transmit the light irradiated by the light source 30 to the first reflective layer 12 through multiple reflections and transmit it out from the other side of the transparent substrate 10. After multiple transmissions, the transmitted light can be transmitted in all directions, covering a wider area, thereby achieving a uniform light output effect and improving the light output uniformity of the backlight module. The second reflective layer 13 is used to reflect the light reflected by the light conversion layer 20, so that the light is transmitted from the side of the transparent substrate 10 that is away from the second reflective layer 13, thereby improving the light output efficiency. The principle can be seen. Figure 2 Schematic diagram of the light propagation path shown.

[0031] The orthographic projection area of ​​the first reflective layer 12 on the same step on the transparent substrate 10 is smaller than the orthographic projection area of ​​the groove 11 where the step is located on the transparent substrate 10, which means that the first reflective layer 12 on the same step does not completely cover the step and the opening between them, thereby preventing the first reflective layer 12 from reflecting all the light, so that no light is emitted from the corresponding position of the transparent substrate 10 on the side facing away from the first reflective layer 12 to form a black spot.

[0032] By providing the stepped groove 11 and providing the first reflective layer 12 on each step, uniform light emission of the backlight module is achieved, and the thickness of the backlight module is reduced, which has the advantage of a simple structure.

[0033] When the light source 30 is a direct-type light source, the first reflective layer 12 can be arranged to allow the emitted light to be emitted in all directions, thereby improving the light emission uniformity of the backlight module and avoiding visual Mura (defective).

[0034] In some embodiments, Figure 1 , Figure 2 As shown, the cross-sectional area of ​​the groove 11 increases successively along the direction approaching the opening of the groove 11; the orthographic projections of the first reflective layers 12 of each level of steps on the transparent substrate 10 do not overlap.

[0035] In this embodiment, the side close to the opening of the groove 11 is closer to the light source 30. The cross-sectional area of ​​the groove 11 here is larger, and the area of ​​the light conversion layer 20 is also larger. In the direction away from the light source 30, the area of ​​the light conversion layer 20 gradually decreases, so that more light from the light source 30 can be transmitted downward through the light conversion layer 20, which is beneficial to increase the light output rate of the backlight module.

[0036] like Figure 1 , Figure 2 As shown, the orthographic projections of the first reflective layers 12 of each step on the transparent substrate 10 do not overlap, and this arrangement can reduce the shielding area of ​​the light emitted by the light source 30 by the first reflective layer 12, and maximize the light emission rate while diverging the light, thereby increasing the light extraction efficiency. This arrangement can also avoid the problem of black spots appearing on the side facing away from the second reflective layer 13 due to shielding by the first reflective layer 12.

[0037] Furthermore, if Figure 1 , Figure 2 As shown, the inner edge of the first reflective layer 12 at the bottom of a step away from the bottom of the groove 11 has an orthographic projection on the transparent substrate 10 that is flush with the outer edge of the first reflective layer 12 at the next step.

[0038] In this embodiment, the first reflective layer 12 of each step is seamlessly connected between the orthographic projections of the transparent substrate 10, and can reflect the light emitted by the light source 30, so that the light is emitted in various directions after multiple reflections by the first reflective layer 12 or the first reflective layer 12 and the second reflective layer 13, thereby improving the light uniformity of the backlight module. Especially for direct-type light sources, this setting can reflect all the light emitted by the direct-type light source directly facing the first reflective layer 12, so that the emitted light is redistributed and the light uniformity is better improved. And this setting can minimize the setting area of ​​the first reflective layer 12 while reflecting all the light directly facing the first reflective layer 12, which is conducive to cost saving.

[0039] In some embodiments, Figure 1 , Figure 2 As shown, the first reflective layer 12 at the bottom of the groove 11 is provided at the center of the bottom of the groove 11 .

[0040] In this embodiment, only one first reflective layer 12 is provided at the bottom of the groove 11 and is provided at the center, so as to facilitate symmetrical and uniform distribution of the first reflective layer 12 on each layer of the upper steps and reduce the difficulty of manufacturing.

[0041] In some embodiments, Figure 3 As shown, the side wall of the groove 11 includes at least two steps. Figure 3 and Figure 1 The difference is that Figure 3 The side wall of the middle groove 11 is a two-step step. Figure 1 The side wall of the middle groove 11 is a three-step step. The more the number of steps, the more times the light emitted by the light source 30 undergoes reflection before being emitted, which is more conducive to the redistribution of the emitted light. However, the more the number of steps, the more complicated the manufacturing process. Therefore, setting the number of steps to 2 can not only ensure the uniform distribution of the emitted light, but also simplify the manufacturing process.

[0042] In some embodiments, Figure 1 , Figure 2 As shown, a continuous protrusion structure 14 or a discontinuous protrusion structure 14 is provided on one side of the transparent substrate 10, and the second reflective layer 13 is provided on the side of the continuous protrusion structure 14 or the discontinuous protrusion structure 14 away from the transparent substrate 10, and the orthographic projection of the continuous protrusion structure 14 or the discontinuous protrusion structure 14 on the transparent substrate 10 overlaps with the orthographic projection of the second reflective layer 13 on the transparent substrate 10.

[0043] In this embodiment, the second reflective layer 13 is arranged on the side of the protruding structure 14 away from the transparent substrate 10, so that the side of the second reflective layer 13 facing the protruding structure 14 naturally forms an uneven surface, which can increase the divergence effect of the second reflective layer 13 on the incident light reflected by the first reflective layer 12 to its surface, and further improve the light output uniformity of the backlight module.

[0044] Specifically, the protrusion structure 14 may be made of a transparent organic resin material.

[0045] In some embodiments, Figure 1 As shown, the distance L1 that the first reflective layer 12 extends beyond the step is 0μm-100μm, for example, it can be 10μm, 20μm, 30μm, 40μm, 50μm, 60μm, 70μm, 80μm, 90μm, etc., and the length L2 that the second reflective layer 13 covers over the openings of the grooves 11 on both adjacent sides is 0μm-100μm, for example, it can be 10μm, 20μm, 30μm, 40μm, 50μm, 60μm, 70μm, 80μm, 90μm, etc.

[0046] In this embodiment, the first reflective layer 12 that extends beyond the first reflective layer 12 can reflect the light emitted by the light source 30. The longer the distance L1 extends, the larger the area of ​​the reflective surface. However, the larger the distance L1 extends, the larger the area of ​​the light source 30 is blocked. It is easy for a black spot to be formed when no light is emitted from the corresponding position on the side facing away from the first reflective layer 12. The portion of the second reflective layer 13 that covers the opening of the groove 11 on both sides can reflect the light emitted by the first reflective layer 12 for a second time, which is beneficial to the redistribution of light. The larger the area of ​​this portion, the more light can be reflected for a second time. However, the larger the area of ​​the portion, the larger the area of ​​the light source 30 is blocked, which is not conducive to the downward transmission of the light emitted by the light source 30. Therefore, the distance of the first reflective layer 12 extending beyond the first reflective layer 12 is more suitable between 0μm and 100μm, and the length L2 covered by the second reflective layer 13 is more suitable between 0μm and 100μm.

[0047] Furthermore, the distance L1 of the first reflective layer 12 beyond the step is 50 μm-100 μm, and the length L2 of the second reflective layer 13 covering the openings of the grooves 11 on both sides adjacent to each other is 50 μm-100 μm.

[0048] In some embodiments, the light conversion layer 20 is a quantum dot color conversion layer or a fluorescent color conversion layer, and the first reflective layer 12 and the second reflective layer 13 are single reflective layers or composite reflective layers.

[0049] In this embodiment, the fluorescence emission of the quantum dot color conversion layer comes from electron transitions, and its color is determined by the nanocrystal particle size of the quantum dots, which is a manifestation of the quantum confinement effect at the nanoscale, while the fluorescence emission of the fluorescent color conversion layer comes from its lattice defects, and its color is produced by doping different ions. Quantum dots have the advantages of high luminous efficiency, narrow spectrum, high color purity, and wide color gamut, so the use of quantum dot color conversion layers can provide a more realistic color display for the backlight module. Phosphor luminescence has the advantage of large color adjustability, so the use of fluorescent color conversion layers can obtain softer or brighter colors to meet different application needs.

[0050] When the first reflective layer 12 is a single-layer reflective layer, it can be, for example, a metal reflective layer with high reflectivity such as metal silver or metal aluminum. When the first reflective layer 12 is a composite reflective layer, for example, it can be a composite reflective layer in which two oxides with different refractive indices are alternately stacked, for example, SiO2 / SiN X / SiO2 / SiN X Or SiO X / TiO2 / SiO X / TiO2 alternately stacked composite reflective layer.

[0051] In some embodiments, Figure 1 , Figure 2 As shown, the portion where the orthographic projection of the luminous light source 30 on the transparent substrate 10 overlaps with the orthographic projection of the light conversion layer 20 on the transparent substrate 10 is the luminous area 31, and the portion where the orthographic projection of the luminous light source 30 on the transparent substrate 10 and the orthographic projection of the light conversion layer 20 on the transparent substrate 10 do not overlap is the pad area 32, and the pad area 32 is electrically connected to the external circuit.

[0052] In this embodiment, the light source 30 emits light only at a position corresponding to the light conversion layer 20 , which can improve the utilization rate of the light source 30 .

[0053] Specifically, the pad areas 32 are respectively located on both sides of the light-emitting area 31, one of the pad areas 32 is electrically connected to the first metal wiring 323 through the first lead 321, and the other pad area 32 is electrically connected to the second metal wiring 324 through the second lead 322. One of the first lead 321 and the second lead 322 is the positive electrode, and the other is the negative electrode. Correspondingly, the anode metal wiring is electrically connected to the positive lead, and the cathode metal wiring is electrically connected to the negative lead, and they are electrically connected to the external circuit through the metal wiring.

[0054] Furthermore, if Figure 1 , Figure 2As shown, the backlight module further includes a first encapsulation layer 40 disposed on the second reflective layer 13 and the light conversion layer 20 on a side away from the transparent substrate 10. The light conversion layer 20 and the second reflective layer 13 are encapsulated by the first encapsulation layer 40, so as to protect the light conversion layer 20 and the second reflective layer 13 from oxidation corrosion caused by water vapor and air.

[0055] Furthermore, a second encapsulation layer 50 is provided on one side of the light source 30 away from the transparent substrate 10, and the second encapsulation layer 50 is used to independently encapsulate each light source 30. The light source 30 is encapsulated by the second encapsulation layer 50 to prevent water vapor and air from entering the light source 30, which is conducive to improving the service life of the light source 30.

[0056] Specifically, the second encapsulation layer 50 may be a white oil layer. In addition to the waterproof and anti-oxidation effects of the encapsulation layer, the white oil layer also has a certain reflective effect, further reducing the light leakage rate of the light source 30 on the white oil layer side.

[0057] In some embodiments, Figure 1 As shown, the backlight module further includes a grating polarizer 60, which is disposed on the side of the transparent substrate 10 facing away from the second reflective layer 13 and the light conversion layer 20. The grating polarizer 60 can convert the outgoing light into linearly polarized light, so that the display device including the backlight module has a higher contrast and a better display effect. The grating polarizer 60 can be, but is not limited to, a metal grating polarizer 60.

[0058] The present application also provides a method for manufacturing a backlight module. Figure 4-Figure 10 The figure shows a schematic diagram of the manufacturing steps of the backlight module, which is used to manufacture the backlight module described above, and at least includes the following steps:

[0059] S1: providing a transparent substrate 10.

[0060] S2: Etching is performed on one side of the transparent substrate 10 to form a groove 11, and at least one first reflective layer 12 is disposed at the bottom of the groove 11, wherein the orthographic projection area of ​​the first reflective layer 12 on the transparent substrate 10 is smaller than the orthographic projection area of ​​the step on the transparent substrate 10, such as Figure 4 , Figure 5 shown.

[0061] Step S3: Fill the groove 11 with a photoresist 15, and the photoresist 15 covers the surface of the second reflective layer 13. Figure 6 The photoresist 15 can protect the first reflective layer 12 and the second reflective layer 13 .

[0062] Step S4: Partially etch the photoresist 15 in the groove 11 to form an etching hole 16 until the bottom surface of the groove 11 is exposed, and the unetched photoresist 15 covers the surface of the first reflective layer 12 and the second reflective layer 13. Figure 7 shown.

[0063] S5: The transparent substrate 10 is further etched through the etching hole 16 to form a stepped groove 11. The cross-sectional area of ​​the groove 11 gradually increases along the direction close to the opening of the groove 11, and at least one first reflective layer 12 is disposed at the bottom of the groove 11. The orthographic projection area of ​​the first reflective layer 12 on the transparent substrate 10 is smaller than the orthographic projection area of ​​the groove 11 at the step on the transparent substrate 10. Figure 8 and Fig. 9 shown.

[0064] S6: Repeat steps S3-S5 until a stepped groove 11 that meets the requirements is formed. Fig.10 shown.

[0065] S7: forming a light conversion layer 20 in the stepped groove 11, such as Fig.11 shown.

[0066] S8: forming a second reflective layer 13 on one side of the transparent substrate 10, the second reflective layer 13 being disposed on one side of the transparent substrate between adjacent grooves 11 and disposed on the same side as the grooves 11. The second reflective layer 13 can be manufactured simultaneously with the first reflective layer 12, further simplifying the manufacturing process, such as Figure 5 shown.

[0067] S9: A first encapsulation layer 40 is formed on the side of the second reflective layer 13 and the light conversion layer 20 away from the transparent substrate 10 to encapsulate the second reflective layer 13 and the light conversion layer 20. Fig.12 shown.

[0068] S10: A light source 30 is arranged on a side of the first encapsulation layer 40 away from the transparent substrate 10, and the orthographic projection of the light source 30 on the transparent substrate 10 at least partially overlaps with the orthographic projection of the light conversion layer 20 on the transparent substrate 10, such as Fig.13 shown.

[0069] The backlight module manufactured by the method does not occupy additional space because the light conversion layer 20 is arranged in the stepped groove 11, which is conducive to reducing the thickness of the backlight module. The first reflective layer 12 arranged at each step can transmit the light irradiated to the first reflective layer 12 by the light source 30 through the other side of the transparent substrate 10 after multiple reflections. After multiple transmissions, the transmitted light can be transmitted in all directions, covering a wider area, thereby achieving a uniform light output effect and improving the light output uniformity of the backlight module. The second reflective layer 13 is used to reflect the light reflected by the light conversion layer 20, so that the light is transmitted from the side of the transparent substrate 10 facing away from the second reflective layer 13, thereby improving the light output efficiency.

[0070] It should be noted that in Fig. 9 , Fig.10 In the process of continuing to form the stepped groove 11, the process of coating the first reflective layer 12 and the second reflective layer 13 with the photoresist 15 is omitted. In order to avoid the etching process affecting the first reflective layer 12 and the second reflective layer 13, before each step of etching the transparent substrate 10, the photoresist 15 is first coated, and then the photoresist 15 is etched to form an etching hole 16.

[0071] A second aspect of the present application provides a display device, which includes the backlight module described above.

[0072] Since the light conversion layer 20 of the backlight module included in the display device is arranged in the stepped groove 11, the light conversion layer 20 does not occupy additional space, which is conducive to reducing the thickness of the backlight module. The first reflective layer 12 arranged at each step can transmit the light irradiated to the first reflective layer 12 by the light source 30 through the other side of the transparent substrate 10 after multiple reflections. After multiple transmissions, the transmitted light can be transmitted in all directions, and the coverage area is wider, thereby achieving a uniform light output effect and improving the light output uniformity of the backlight module. The second reflective layer 13 is used to reflect the light reflected by the light conversion layer 20, so that the light is transmitted from the side of the transparent substrate 10 that is away from the second reflective layer 13, thereby improving the light output efficiency.

[0073] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0074] Each embodiment in this specification is described in a related manner, and the same or similar parts between the embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

[0075] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A backlight module, characterized in that: The backlight module comprises: A transparent substrate, wherein a plurality of grooves are provided on one side of the transparent substrate, the sidewalls of the grooves are arranged in a step-like manner, each step is provided with at least one first reflective layer, and the orthographic projection area of ​​the first reflective layer of the same step on the transparent substrate is smaller than the orthographic projection area of ​​the groove where the step is located on the transparent substrate; A light conversion layer, wherein the light conversion layer is filled in the groove; A plurality of light sources, wherein the light sources are located on a side of the light conversion layer away from the transparent substrate, and the orthographic projection of the light source on the transparent substrate at least partially overlaps with the orthographic projection of the light conversion layer on the transparent substrate; The second reflective layer is disposed on one side of the transparent substrate between adjacent grooves and on the same side as the grooves.

2. The backlight module according to claim 1, characterized in that: The cross-sectional area of ​​the groove increases successively along the direction approaching the opening of the groove; the orthographic projections of the first reflective layer of each level of steps on the transparent substrate do not overlap.

3. The backlight module according to claim 2, characterized in that: The inner edge of the first reflective layer at the bottom of a step away from the bottom of the groove has an orthographic projection on the transparent substrate flush with the outer edge of the first reflective layer at the next step.

4. The backlight module according to claim 3, characterized in that: The first reflective layer at the bottom of the groove is provided at the center of the bottom of the groove.

5. The backlight module according to claim 1, characterized in that: The side wall of the groove includes at least two steps.

6. The backlight module according to claim 1, characterized in that: A continuous convex structure or a discontinuous convex structure is provided on one side of the transparent substrate, and the second reflective layer is provided on a side of the continuous convex structure or the discontinuous convex structure away from the transparent substrate, and the orthographic projection of the continuous convex structure or the discontinuous convex structure on the transparent substrate overlaps with the orthographic projection of the second reflective layer on the transparent substrate.

7. The backlight module according to any one of claims 1 to 6, characterized in that: The first reflective layer exceeds the step by a distance of 0 μm-100 μm, and the second reflective layer covers the openings of the grooves on two adjacent sides by a length of 0 μm-100 μm.

8. The backlight module according to any one of claims 1 to 6, characterized in that: The light conversion layer is a quantum dot conversion layer or a fluorescent color conversion layer, and the first reflection layer and the second reflection layer are single-layer reflection layers or composite reflection layers.

9. The backlight module according to any one of claims 1 to 6, characterized in that: The portion where the orthographic projection of the luminous light source on the transparent substrate overlaps with the orthographic projection of the light conversion layer on the transparent substrate is a luminous area, and the portion where the orthographic projection of the luminous light source on the transparent substrate does not overlap with the orthographic projection of the light conversion layer on the transparent substrate is a pad area, and the pad area is electrically connected to an external circuit.

10. The backlight module according to any one of claims 1 to 6, characterized in that: The backlight module also includes a first packaging layer arranged on the side of the second reflective layer and the light conversion layer away from the transparent substrate; a second packaging layer is arranged on the side of the light source away from the transparent substrate, and the second packaging layer is used to independently package each of the light sources.

11. The backlight module according to claim 10, characterized in that: The second encapsulation layer is a white oil layer.

12. The backlight module according to any one of claims 1 to 6, characterized in that: The backlight module further comprises a grating polarizer, and the grating polarizer is arranged on a side of the transparent substrate facing away from the second reflective layer and the light conversion layer.

13. A display device, characterized in that: The display device comprises the backlight module according to any one of claims 1-12.

Images