Display module, preparation method thereof, and display device

Abstract

The present application discloses a display module, a preparation method thereof, and a display device. By providing a diffusion unit on a side of at least one LED chip facing away from the substrate, the diffusion unit includes a first diffusion part and a second diffusion part penetrating the first diffusion part. The second diffusion part includes a main body part and a bifurcated part, so that at least part of the light emitted from the position directly facing the LED chip can be collected by the main body part and totally reflected within the main body part and the bifurcated part. Since the included angle between the extending direction of the bifurcated part and the extending direction of the main body part is greater than zero, the light emitted from the bifurcated part is offset in a direction parallel to the surface of the substrate compared with the initial light emitted from the LED chip, that is, the emission angle of the light emitted from the LED chip is enlarged, so that the luminous intensity at the position directly facing the LED chip is equivalent to the luminous intensity between adjacent LED chips, thereby reducing or eliminating the phenomenon of uneven bright and dark "starry sky" in the display panel and improving the uniformity of the display brightness of the display panel.

Description

Technical Field

[0001] The present application relates to the field of display technologies, and in particular, to a display module, a preparation method thereof, and a display device. Background Art

[0002] With the development of display technologies, a large number of Micro LEDs (Light-Emitting Diodes) or Mini LEDs have been integrated as display light sources on an active addressing driving substrate, so as to realize individual control and lighting of each LED, greatly improving the resolution of a displayed image. However, at present, when a large number of Micro LEDs or Mini LEDs are used as display light sources, a phenomenon of uneven bright and dark like a sky full of stars always appears in a display panel. Summary of the Invention

[0003] To solve the above technical problems, embodiments of the present application provide a display module, a preparation method thereof, and a display device, so as to weaken or eliminate the phenomenon of uneven bright and dark like a sky full of stars in a display panel, and improve the uniformity of the display brightness of the display panel.

[0004] To achieve the above object, embodiments of the present application provide the following technical solutions:

[0005] A display module, comprising:

[0006] A substrate;

[0007] A plurality of LED chips located on the substrate;

[0008] At least one side of the LED chip facing away from the substrate is provided with a diffusion unit, the diffusion unit includes a first diffusion part and a second diffusion part penetrating through the first diffusion part, and the refractive index of the second diffusion part is greater than that of the first diffusion part;

[0009] The second diffusion part includes a main body part and a bifurcated part, the included angle between the extending direction of the main body part and the extending direction of the bifurcated part is greater than zero, the height of the main body part in a first direction is less than the height of the first diffusion part in the first direction, and the first direction is perpendicular to the surface of the substrate;

[0010] A first end surface of the main body part is located on a surface of the second diffusion part close to the LED chip, and a positive projection of the first end surface of the main body part on the surface of the substrate at least partially overlaps with a positive projection of the LED chip on the surface of the substrate.

[0011] A preparation method of a display module, comprising:

[0012] Providing a substrate;

[0013] Form a plurality of LDE chips on the substrate;

[0014] Form a diffusion unit on one side of at least one of the LED chips facing away from the substrate. The diffusion unit includes a first diffusion part and a second diffusion part penetrating through the first diffusion part. The refractive index of the second diffusion part is greater than that of the first diffusion part;

[0015] Wherein, the second diffusion part includes a main body part and a bifurcated part. The included angle between the extending direction of the main body part and the extending direction of the bifurcated part is greater than zero. The height of the main body part in the first direction is less than the height of the first diffusion part in the first direction. The first direction is perpendicular to the surface of the substrate;

[0016] The first end face of the main body part is located on the surface of the second diffusion part close to the LED chip. The orthographic projection of the first end face of the main body part on the surface of the substrate at least partially overlaps with the orthographic projection of the LED chip on the surface of the substrate.

[0017] A display device includes the above display module.

[0018] Compared with the prior art, the above technical solution has the following advantages:

[0019] In the display module provided by the embodiment of the present application, a diffusion unit is provided on one side of at least one LED chip facing away from the substrate. The diffusion unit includes a first diffusion part and a second diffusion part penetrating through the first diffusion part. The second diffusion part includes a main body part and a bifurcated part. In the direction perpendicular to the surface of the substrate, the height of the main body part is less than the height of the first diffusion part. Since the first end face of the main body part is located on the surface of the second diffusion part close to the LED chip, and the orthographic projection of the first end face of the main body part on the surface of the substrate at least partially overlaps with the orthographic projection of the LED chip on the surface of the substrate, therefore, at least part of the light emitted from the position directly opposite to the LED chip can be collected by the main body part; and because the refractive index of the second diffusion part is greater than that of the first diffusion part, the light collected by the main body part can be totally reflected in the main body part and the bifurcated part, and because the included angle between the extending direction of the bifurcated part and the extending direction of the main body part is greater than zero, the exit angle of the light emitted from the bifurcated part is offset in the direction parallel to the surface of the substrate compared with the exit angle of the initial light emitted from the LED chip, that is, the exit angle of the light emitted from the LED chip is enlarged, so that the luminous intensity at the position directly opposite to the LED chip is equivalent to the luminous intensity between adjacent LED chips, thereby weakening or eliminating the starry sky phenomenon of uneven brightness in the display panel and improving the uniformity of the display brightness of the display panel. Description of the Drawings

[0020] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for describing the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0021] Figure 1 It is a schematic structural diagram of a display module using a Mini LED as a display light source in the prior art;

[0022] Figure 2 It is a schematic cross-sectional structure diagram of a display module provided by an embodiment of the present application;

[0023] Figure 3 It is a schematic cross-sectional structure diagram of a part corresponding to an LED chip in a display module provided by an embodiment of the present application;

[0024] Figures 4(a) - 4(c) It is a schematic diagram of the transmission optical path of the light emitted from the position directly opposite to the LED chip in the diffusion unit in the display module provided by an embodiment of the present application;

[0025] Figure 5 It is a schematic cross-sectional structure diagram of a part corresponding to an LED chip in a display module provided by another embodiment of the present application;

[0026] Figure 6 It is a schematic cross-sectional structure diagram of a part corresponding to an LED chip in a display module provided by still another embodiment of the present application;

[0027] Figure 7 It is a schematic cross-sectional structure diagram of a part corresponding to an LED chip in a display module provided by yet another embodiment of the present application;

[0028] Figures 8(a) - 8(e) For forming Figure 7 During the process of the device structure shown, schematic diagrams of the device structures corresponding to each process step;

[0029] Figure 9 For Figure 7 In the device structure shown, a bottom view of the diffusion unit in the direction away from the substrate;

[0030] Figure 10 For Figure 7 In the device structure shown, a top view of the diffusion unit in the direction towards the substrate;

[0031] Figure 11 It is a schematic cross-sectional structure diagram of a part corresponding to an LED chip and its light transmission optical path diagram in a display module provided by still another embodiment of the present application;

[0032] Figure 12 In the display module provided by another embodiment of the present application, it is a schematic cross-sectional structure diagram corresponding to a part of an LED chip and a schematic light transmission optical path diagram thereof;

[0033] FIG. 13(a) is a schematic cross-sectional structure diagram corresponding to a part of an LED chip in the display module provided by another embodiment of the present application;

[0034] FIG. 13(b) is a schematic light transmission optical path diagram in the device structure shown in FIG. 13(a);

[0035] FIG. 14(a) is a schematic cross-sectional structure diagram corresponding to a part of an LED chip in the display module provided by another embodiment of the present application;

[0036] FIG. 14(b) is a schematic light transmission optical path diagram in the device structure shown in FIG. 14(a);

[0037] Figure 15 In the display module provided by another embodiment of the present application, it is a schematic cross-sectional structure diagram corresponding to a part of an LED chip and a schematic light transmission optical path diagram thereof;

[0038] Figure 16 In the display module provided by another embodiment of the present application, it is a schematic cross-sectional structure diagram corresponding to a part of an LED chip and a schematic light transmission optical path diagram thereof;

[0039] Figure 17 In the display module provided by another embodiment of the present application, it is a schematic cross-sectional structure diagram corresponding to a part of an LED chip and a schematic light transmission optical path diagram thereof;

[0040] Figure 18 It is a schematic flow chart of a method for manufacturing a display module provided by an embodiment of the present application;

[0041] Figure 19 In the method for manufacturing a display module provided by an embodiment of the present application, it is a schematic flow chart of a formation process of a diffusion unit;

[0042] Figure 20 It is a schematic structure diagram of a display device provided by an embodiment of the present application. Detailed Embodiments

[0043] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0044] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, the present application may be implemented in other ways different from those described herein. Those skilled in the art can make similar generalizations without departing from the spirit of the present application. Therefore, the present application is not limited by the specific embodiments disclosed below.

[0045] Secondly, the present application will be described in detail in conjunction with the schematic diagrams. When detailing the embodiments of the present application, for ease of illustration, the cross-sectional views showing the device structure will be enlarged locally in a non-generalized scale, and the schematic diagrams are only examples and should not limit the scope of protection of the present application herein. In addition, in actual production, three-dimensional spatial dimensions including length, width, and depth should be included.

[0046] As described in the background art section, currently, when a large number of Micro LEDs or Mini LEDs are used as display light sources, there will always be a phenomenon of uneven bright and dark spots like a starry sky in the display panel.

[0047] The inventors have found through research that this is because the light emission intensity is high at the directly facing position of the LED chip, while the light emission intensity is low at the side position, that is, the light emission intensities at the directly facing position and the side position of the LED chip are uneven.

[0048] Specifically, Figure 1 shows a schematic structural diagram of a display module using Mini LEDs as a display light source in the prior art. As Figure 1 shown, the display module includes a substrate 01, a Mini LED chip 02, a packaging layer 03, a light guide plate 04, a support 05, a display panel 06, and a housing 07. Although the light emitted by the Mini LED chip 02 is transmitted in all directions, the light emission intensity is high at the directly facing position of the Mini LED chip 02, while the light emission intensity is low at the side position of the Mini LED chip 02. As a result, the brightness is high at the position corresponding to the Mini LED chip 02 in the display panel 06, while the brightness is low at the position corresponding to the space between two adjacent Mini LED chips 02, that is, there is a phenomenon of uneven bright and dark spots like a starry sky in the display panel 06, and the display brightness of the display panel is uneven.

[0049] In response to this, the solution adopted in the prior art is: a light guide plate 04 is provided on the side of the Mini LED chip 02 facing away from the substrate 01, and a certain distance is set between the Mini LED chip 02 and the light guide plate 04 to mix the light emitted by the Mini LED chip 02 using the light guide plate 04, thereby improving the uniformity of the display brightness at various positions of the display panel.

[0050] However, as Figure 1As shown, the distance between the Mini LED chip 02 and the light guide plate 04 cannot be too close, otherwise there will still be a problem of uneven display brightness at various positions of the display panel, which is obviously not conducive to the further thinning of the display module. Moreover, the light guide plate 04 needs to be supported by a support member 05, and the support member 05 is located at the edge of the light guide plate 04. However, when the size of the display panel is large, the light guide plate 04 is easily deformed due to too large a span.

[0051] It can be seen that the prior art uses a light guide plate to solve the phenomenon of uneven brightness like "starry sky" in the display panel, which not only limits the further thinning of the display module, but also the light guide plate is unstable and easily deformed due to too large a span.

[0052] In view of this, the embodiments of the present application provide a display module. Figure 2 The cross-sectional structure schematic diagram of the display module provided by the embodiments of the present application is given, as Figure 2 shown, the display module includes:

[0053] A substrate 100;

[0054] A plurality of LED chips 200 located on the substrate 100;

[0055] On at least one side of the LED chip 200 facing away from the substrate 100, a diffusion unit 300 is provided. The diffusion unit 300 includes a first diffusion part 310 and a second diffusion part 320 penetrating the first diffusion part 310. The refractive index of the second diffusion part 320 is greater than that of the first diffusion part 310.

[0056] Figure 3 The cross-sectional structure schematic diagram of a part corresponding to one LED chip in the display module provided by the embodiments of the present application is given, as Figure 3 shown, the second diffusion part 320 includes a main body part 321 and a bifurcated part 322. The included angle between the extending direction of the main body part 321 and the extending direction of the bifurcated part 322 is greater than zero. The height of the main body part 321 in the first direction is less than the height of the first diffusion part 310 in the first direction. The first direction is perpendicular to the surface of the substrate.

[0057] The first end face of the main body part 321 is located on the surface of the second diffusion part 320 close to the LED chip 200. The orthographic projection of the first end face of the main body part 321 on the surface of the substrate 100 overlaps at least partially with the orthographic projection of the LED chip 200 on the surface of the substrate 100.

[0058] In this embodiment, in combination with Figure 2 and Figure 3As shown, since the second diffusion portion 320 penetrates the first diffusion portion 310, and in the second diffusion portion 320, the first end surface of the main body portion 321 is located on the surface of the second diffusion portion 320 close to the LED chip 200, and the height of the main body portion 321 along the first direction is less than the height of the first diffusion portion 310 along the first direction, therefore, the main body portion 321 in the second diffusion portion 320 is arranged close to the side of the LED chip, and the fork portion 322 extends from the side of the main body portion 321 away from the LED chip.

[0059] Since the angle between the extension direction of the fork portion 322 and the extension direction of the main body portion 321 is greater than zero, Figure 2 and Figure 3 As shown, there is a accommodating cavity in the middle of the bifurcated portion 322, and the accommodating cavity is filled with a portion of the first diffusion portion 310, that is, the second diffusion portion 320 that penetrates the first diffusion portion 310 divides the first diffusion portion 310 into two parts, one part surrounds the second diffusion portion 320, and the other part is surrounded by the second diffusion portion 320, that is, the side surfaces of the second diffusion portion 320 are all interfaces between the second diffusion portion 320 and the first diffusion portion 310, and the refractive index of the second diffusion portion 320 is greater than the refractive index of the first diffusion portion 310. Therefore, when light is incident from the second diffusion portion 320 to the first diffusion portion 310, it is equivalent to being incident from a denser medium to a less dense medium, and total reflection can occur as long as the incident angle is greater than the critical angle of total reflection, that is, light emitted from the LED chip with an incident angle greater than the total reflection can be totally reflected in the main body and the bifurcated portion.

[0060] It should be noted that reference Figure 2 and Figure 3 As shown, the height of the accommodating cavity in the middle of the bifurcated portion 322 along the first direction may be equal to the height of the bifurcated portion 322 along the first direction, or may be less than the height of the bifurcated portion 322 along the first direction, depending on specific circumstances.

[0061] It should also be noted that the reference Figure 3 As shown, the main body 321 and the bifurcated portion 322 in the second diffuser 320 are a continuous integral structure rather than two structures spliced together. Here, the second diffuser 320 is divided into the main body 321 and the bifurcated portion 322. Figure 3 The dotted line in the middle shows a division of the functions and extension directions of the two parts for the sake of ease of explanation and understanding, which are explained separately below.

[0062] First, the functions of the main body portion 321 and the branching portion 322 of the second diffuser portion 320 are described.

[0063] For the main body 321, since the orthographic projection of the first end face of the main body 321 on the surface of the substrate 100 at least partially overlaps with the orthographic projection of the LED chip 200 on the surface of the substrate 100, that is, the orthographic projection of the first end face of the main body 321 on the surface of the substrate 100 and the orthographic projection of the LED chip 200 on the surface of the substrate 100 can partially overlap, or the orthographic projection of the first end face of the main body 321 on the surface of the substrate 100 can cover the orthographic projection of the LED chip 200 on the surface of the substrate 100, and the orthographic projection of the LED chip 200 on the surface of the substrate 100 can also cover the orthographic projection of the first end face of the main body 321 on the surface of the substrate 100, therefore, at least part of the light emitted from the position directly opposite to the LED chip 200 can be collected by the main body 321, that is, the function of the main body 321 is to collect at least part of the light emitted from the position directly opposite to the LED chip 200, and the light with an incident angle greater than the critical angle of total reflection among these light rays is totally reflected in the main body 321 and the fork portion 322.

[0064] In order to enable the main body 321 to collect as much light as possible with an incident angle greater than the critical angle of total reflection emitted from the position directly opposite the LED chip 200, preferably, the orthographic projection of the first end face of the main body 321 on the surface of the substrate 100 covers the orthographic projection of the LED chip 200 on the surface of the substrate 100.

[0065] For the fork portion 322, since the angle between the extension direction of the fork portion 322 and the extension direction of the main body portion 321 is greater than zero, the light emitted from the fork portion 322 is offset in a direction parallel to the substrate surface compared to the initial light emitted from the LED chip 200, thereby expanding the emission angle of the light emitted by the LED chip. In other words, the function of the fork portion 322 is to offset at least part of the light emitted from the LED chip facing the main body portion 321 in a direction parallel to the substrate surface.

[0066] Since the luminous intensity at the position directly opposite the LED chip 200 is large, while the luminous intensity between adjacent LED chips 200 (i.e., the side position of the LED chip) is small, the display module provided in the embodiment of the present application utilizes the main body 321 to collect at least part of the light emitted from the position directly opposite the LED chip, and utilizes the forked portion 322 to offset this part of the light in a direction parallel to the surface of the substrate, thereby expanding the emission angle of the light emitted by the LED chip, so that the luminous intensity at the position directly opposite the LED chip is equivalent to the luminous intensity between adjacent LED chips, so as to weaken or eliminate the uneven brightness and brightness of the star-shaped phenomenon in the display panel, so that the display brightness of each part of the display panel is more uniform.

[0067] Specifically, the forked portion 322 offsets at least part of the light emitted from the LED chip facing the main body 321 in a direction parallel to the substrate surface, including:

[0068] The angle between the emitted light passing through the main body portion 321 and the bifurcated portion 322 and emitted from the LED chip 200 and the first direction becomes larger compared with the initial light emitted from the LED chip 200;

[0069] and / or,

[0070] The position of the emitted light passing through the main body portion 321 and the bifurcated portion 322 and emitted from the LED chip 200 is shifted toward the side position of the LED chip compared with the initial light emitted from the LED chip 200.

[0071] Specifically, as shown in FIGS. 4(a) and 4(b), when the incident angle of the light emitted from the LED chip 200 is greater than the total reflection critical angle, total reflection occurs in the main body portion 321 and the bifurcated portion 322. At this time, the angle between the light emitted from the bifurcated portion 322 and the first direction becomes larger compared with the initial light emitted from the LED chip 200, that is, the angle with the direction parallel to the substrate surface becomes smaller, so as to shift in the direction parallel to the substrate surface.

[0072] As shown in FIG. 4(c) again, when the incident angle of the light emitted from the LED chip 200 is greater than the total reflection critical angle, total reflection occurs in the main body portion 321 and the bifurcated portion 322. At this time, the position of the light emitted from the bifurcated portion 322 is shifted toward the side position of the LED chip compared with the initial light emitted from the LED chip 200, that is, its position is shifted toward the position between adjacent LED chips, so as to also shift in the direction parallel to the substrate surface.

[0073] Secondly, the extending directions of the main body portion 321 and the bifurcated portion 322 in the second diffusion portion 320 will be described.

[0074] In this embodiment, the angle between the extending direction of the main body portion 321 and the extending direction of the bifurcated portion 322 in the second diffusion portion 320 is greater than zero. Then, taking the first direction pointing from the surface of the substrate 100 to the LED chip 200 as the reference direction, the angle between the extending direction of the main body portion 321 and the reference direction is different from the angle between the extending direction of the bifurcated portion 322 and the reference direction. It should be noted that since the first direction is perpendicular to the substrate surface, the reference direction is also perpendicular to the substrate surface and points from the substrate surface to the LED chip, that is, the reference direction is the normal direction of the surface of the substrate 100.

[0075] When the angle between the extending direction of the main body portion 321 and the reference direction is different, the second diffusion portion 320 can present different shapes. Optionally, in an embodiment of the present application, as Figure 3 、 Figures 4(a) - 4(c) shown, the angle between the extending direction of the main body portion 321 and the reference direction (that is Figure 3 、Figures 4(a) - 4(c) In other words, the extension direction of the main body 321 is the same as the reference direction. At this time, the incident angle of more light emitted from the LED chip 200 can meet the critical angle of total reflection and thus be collected by the main body. Figure 5 As shown, the extension direction of the main body 321 is parallel to the reference direction (i.e. Figure 5 The angle between the first direction (marked as the first direction) can also be greater than zero and less than 90 degrees. At this time, the main body 321 can also offset the collected light in a direction parallel to the substrate surface.

[0076] When the angle between the extension direction of the fork portion 322 and the reference direction is different, the second diffusion portion 320 may also present different shapes. Taking the extension direction of the main body 321 as an example, different shapes of the second diffusion portion 320 when the angle between the extension direction of the fork portion 322 and the reference direction is different are described below.

[0077] Optionally, in one embodiment of the present application, Figure 3 , Figures 4(a) - 4(c) As shown, the extension direction of the bifurcated portion 322 is consistent with the reference direction (i.e. Figure 3 , Figures 4(a) - 4(c) The angle between the first direction marked in the figure is greater than zero and less than 90 degrees. At this time, the outgoing light of the forked portion 322 is emitted to the side away from the substrate 100. Optionally, in another embodiment of the present application, Figure 6 As shown, the extension direction of the bifurcated portion 322 is consistent with the reference direction (i.e. Figure 6 The angle between the first direction marked in (the first direction marked in) is greater than 90 degrees and less than 180 degrees. At this time, the outgoing light of the fork portion is emitted toward the side facing the substrate 100. A reflective layer can be provided on the side of the diffusion unit 300 close to the LED chip 100 to emit the outgoing light of the fork portion 322 toward the side away from the substrate 100, or directly from the side facing the substrate 100, that is, the display module can emit light from both the side facing away from the substrate and the side facing the substrate.

[0078] It should be noted that, in the present embodiment, since the angle between the extension direction of the fork portion 322 and the extension direction of the main body portion 321 is greater than zero, the angle between the outgoing light emitted from the LED chip 200 and passing through the main body portion 321 and the fork portion 322 and the first direction will become larger than the initial light emitted from the LED chip 200, thereby ensuring that the outgoing light emitted from the LED chip and passing through the main body portion and the fork portion is offset in a direction parallel to the surface of the substrate.

[0079] Optionally, in an embodiment of the present application, the included angle between the extending direction of the bifurcated portion 322 and the reference direction is greater than zero and less than 90 degrees. At this time, the second end face of the bifurcated portion 322 is located on the surface of the second diffusion portion 320 facing away from the LED chip 200. Then, in order to improve the light homogenization effect of the diffusion unit, it can be set that the orthographic projection of the second end face of the bifurcated portion 322 on the substrate surface and the orthographic projection of the LED chip 200 on the substrate surface are at least partially non-overlapping, so as to further shift the position of the outgoing light emitted from the LED chip 200 passing through the main body portion 321 and the bifurcated portion 322 in a direction parallel to the substrate surface while ensuring that the outgoing light emitted from the LED chip 200 passing through the main body portion 321 and the bifurcated portion 322 is shifted in a direction parallel to the substrate surface, so as to achieve a better light homogenization effect.

[0080] It can be understood that the second end face of the bifurcated portion 322 includes an inner boundary and an outer boundary, and the outer boundary of the second end face of the bifurcated portion surrounds its inner boundary. In this embodiment, the fact that the orthographic projection of the second end face of the bifurcated portion 322 on the substrate surface and the orthographic projection of the LED chip 200 on the substrate surface are at least partially non-overlapping specifically means that the orthographic projection of the outer boundary of the second end face of the bifurcated portion 322 on the substrate surface and the orthographic projection of the LED chip 200 on the substrate surface are at least partially non-overlapping, so that the position of the outgoing light emitted from the LED chip 200 passing through the main body portion 321 and the bifurcated portion 322 can also be shifted in a direction parallel to the substrate surface.

[0081] Optionally, in other embodiments of the present application, even if the orthographic projection of the outer boundary of the second end face of the bifurcated portion 322 on the substrate surface intersects with the orthographic projection of the LED chip 200 on the substrate surface, then, due to the included angle between the extending direction of the bifurcated portion 322 and the extending direction of the main body portion 321 being greater than zero, it is also possible to shift the outgoing light emitted from the LED chip passing through the main body portion and the bifurcated portion in a direction parallel to the substrate surface.

[0082] In order to further improve the light homogenization effect of the diffusion unit, optionally, in an embodiment of the present application, the orthographic projection of the first end face of the main body portion 321 on the substrate surface and the orthographic projection of the second end face of the bifurcated portion 322 on the substrate surface both coincide with the center of the orthographic projection of the LED chip 200 on the substrate surface, so that the main body portion 321 can collect the light with a relatively high luminous intensity at the position directly opposite to the LED chip 200 and shift it in a direction parallel to the substrate surface through the bifurcated portion.

[0083] Furthermore, in an embodiment of the present application, the first end face of the main body portion 321 is circular or regular polygon, so that the light emitted from the position directly opposite to the LED chip can be uniformly collected by the main body portion 321; the second end face of the bifurcated portion 322 includes an inner boundary and an outer boundary, and the outer boundary of the second end face of the bifurcated portion 322 surrounds its inner boundary. The figures formed by the outer boundary and the inner boundary of the second end face of the bifurcated portion 322 are both circular or regular polygon, so that the bifurcated portion 322 can also uniformly shift the light emitted from the position directly opposite to the LED chip collected by the main body portion 321 to the side edges around the LED chip, thereby obtaining a better light homogenization effect.

[0084] Considering that in practical applications, the LED chip 200 usually needs to be encapsulated. Therefore, as Figures 2 - 6 shown, the display module may further include: an encapsulation layer 400 located between the LED chip 200 and the diffusion unit 300. The encapsulation layer 400 covers the LED chip 200. The refractive index of the first diffusion portion 310 is not less than the refractive index of the encapsulation layer 400, that is, the refractive indices of the first diffusion portion 310 and the second diffusion portion 320 are both not less than the refractive index of the encapsulation layer 400. When the light emitted from the position directly opposite to the LED chip 200 enters the diffusion unit 300 (including the first diffusion portion 310 and the second diffusion portion 320) through the encapsulation layer 400, it is equivalent to entering from an optically thinner medium into an optically denser medium, so that it can enter the diffusion unit 300 more easily for diffusion.

[0085] It should be noted that the display module provided by the embodiment of the present application can be used as a backlight module to provide a backlight source for the display panel, or can be directly used for display, depending on the specific situation.

[0086] Thus, it can be seen that the display module provided by the embodiment of the present application, by providing a diffusion unit on the side of the LED chip facing away from the substrate, uses the main body portion in the diffusion unit to collect at least part of the light emitted from the position directly opposite to the LED chip, and uses the bifurcated portion in the diffusion unit to shift the light collected by the main body portion in the direction parallel to the surface of the substrate, thereby expanding the emission angle of the light emitted by the LED chip, and further making the luminous intensity at the position directly opposite to the LED chip equivalent to the luminous intensity between adjacent LED chips, weakening or eliminating the "starry sky" phenomenon of uneven brightness in the display picture, and improving the uniformity of the display brightness of the display panel.

[0087] In the above embodiments, when the extending direction of the main body portion 321 is the same as the reference direction, and the orthographic projection of the first end face of the main body portion 321 on the substrate surface overlaps at least partially with the orthographic projection of the LED chip 200 on the substrate surface, more light rays satisfying the total reflection condition emitted from the position directly opposite to the LED chip can be collected; when the included angle between the extending direction of the bifurcated portion 322 and the reference direction is greater than zero and less than 90 degrees, the light rays emitted from the bifurcated portion 322 are emitted towards the side away from the substrate. At this time, the second end face of the bifurcated portion 322 is located on the surface of the second diffusion portion 320 facing away from the LED chip, and when the orthographic projection of the second end face of the bifurcated portion 322 on the substrate surface does not overlap at least partially with the orthographic projection of the LED chip 200 on the substrate surface, the light homogenizing effect is better. On this basis, the implementation manner of the diffusion unit 300 in the display module provided in the embodiments of the present application will be further described below.

[0088] Optionally, in an embodiment of the present application, as Figure 7 shown, the second diffusion portion 320 includes a plurality of diffusion beams 10 arranged at intervals. The diffusion beam 10 includes a vertical section 11 and a bent section 12. The vertical section 11 of the diffusion beam 10 is parallel to the first direction, and the included angle between the bent section 12 of the diffusion beam 10 and the first direction is greater than zero. Specifically, the included angle between the bent section 12 of the diffusion beam 10 and the reference direction (the first direction pointing from the surface of the substrate 100 to the LED chip 200, that is, Figure 7 the first direction marked in

[0089] is greater than zero and less than 90 degrees;

[0090] The main body portion 321 includes the vertical sections 11 of the respective diffusion beams 10, and the first end face of the main body portion 321 includes the end faces of the vertical sections 11 of the respective diffusion beams 10 facing the LED chip 200;

[0091] The bifurcated portion 322 includes the bent sections 12 of the respective diffusion beams 10, and the second end face of the bifurcated portion 322 includes the end faces of the bent sections 12 of the respective diffusion beams 10 away from the LED chip 200.

[0092] In this embodiment, since the angle between the bent segment 12 of the diffusion beam 10 and the reference direction is greater than zero and less than 90 degrees, the exit angle of the light rays emitted from the diffusion beam 10 is offset in a direction parallel to the surface of the substrate 200 compared to the exit angle of the initial light rays emitted from the LED chip 200. And in this embodiment, the orthographic projection of the second end face of the bifurcated portion 322 on the substrate surface does not overlap at least partially with the orthographic projection of the LED chip 200 on the substrate surface, that is, the orthographic projection of the end face of at least a part of the bent segment 12 of the diffusion beam 10 away from the LED chip on the substrate surface does not overlap with the orthographic projection of the LED chip 200 on the substrate surface. As a result, the exit position of the light rays emitted from at least a part of the diffusion beam 10 is offset towards the side position of the LED chip compared to the exit position of the initial light rays emitted from the LED chip 200, thereby making the luminous intensity at the position directly opposite the LED chip equivalent to the luminous intensity between adjacent LED chips, reducing or eliminating the "starry sky" phenomenon of uneven brightness and darkness in the display screen, and improving the uniformity of the display brightness of the display module.

[0093] Specifically, in the actual manufacturing process, first, as shown in FIG. 8(a), the LED chip 200 is encapsulated to form an encapsulation layer 400.

[0094] Secondly, as shown in FIG. 8(b), a first glue layer 311 is coated on the side of the encapsulation layer 400 away from the substrate 100, and the first glue layer 311 is semi-cured.

[0095] Then, as shown in FIG. 8(c), a plurality of diffusion beams 10 are inserted through and into the semi-cured first glue layer 311, and the first glue layer 311 is cured. Since the diffusion beam 10 is a material wire made of a high-refractive-index material and has a certain stiffness, the diffusion beam 10 can be inserted through and into the semi-cured first glue layer 311.

[0096] After that, as shown in FIGS. 8(d) and 8(e), a second adhesive layer 312 is continuously coated on the surface of the first adhesive layer 311 facing away from the substrate 100, and a pressing fixture is used to apply pressure to each diffusion beam 10 in the direction towards the substrate 100 for pressing, so that each diffusion beam 10 is pressed into a vertical section 11 and a bent section 12 under the action of the pressure; since one end of each diffusion beam 10 close to the LED chip 200 is fixed by the cured first adhesive layer 311, when each diffusion beam 10 is pressed, it is similar to pressing a lever fixed at one end, so that each diffusion beam 10 deforms under the action of the pressure and disperses around; at this time, the second adhesive layer 312 can be coated first and then each diffusion beam 10 is pressed, or each diffusion beam 10 can be pressed first and then the second adhesive layer 312 is coated. Note that when the second adhesive layer 312 is coated first and then each diffusion beam 10 is pressed, the coating thickness of the second adhesive layer 312 cannot exceed the height of the diffusion beam 10 in the first direction, so as to facilitate the pressing of each diffusion beam 10;

[0097] Finally, the second adhesive layer 312 is also cured to form the diffusion unit 300, that is, the Figure 7 structure shown.

[0098] It can be seen that in this embodiment, the first adhesive layer 311 and the second adhesive layer 312 form the first diffusion part 310, and the first adhesive layer 311 and the second adhesive layer 312 can be made of the same material. The main body part 321 of the second diffusion part 320 includes the vertical sections of each diffusion beam 10, and the bifurcated part 322 of the second diffusion part 320 includes the bent sections 12 of each diffusion beam 10. The first end face of the main body part 321 includes the end face of the vertical section 11 of each diffusion beam 10 facing the LED chip 200, and the second end face of the bifurcated part 322 includes the end face of the bent section 12 of each diffusion beam 10 away from the LED chip 200.

[0099] It should be noted that Figure 9 FIG. gives a bottom view of the diffusion unit corresponding to one LED chip in the display module provided by the embodiment of the present application in the direction away from the substrate. From Figure 9 it can be seen that in this embodiment, the end face of one end of the vertical section 11 of the diffusion beam 10 facing the LED chip 200 is as Figure 9 shown by the white circle in, and the first end face of the main body part 321 includes the end face of the vertical section 11 of each diffusion beam 10 facing the LED chip 200.

[0100] Figure 10 FIG. gives a top view of the diffusion unit corresponding to one LED chip in the display module provided by the embodiment of the present application in the direction towards the substrate. From Figure 10It can be seen that in this embodiment, the end face of the bent section 12 of the diffusion beam 10 away from the LED chip 200 is as shown in Figure 10 the white circle in, and the second end face of the bifurcated portion 322 includes the end faces of the bent sections 12 of the respective diffusion beams 10 away from the LED chip.

[0101] It should also be noted that with reference to Figure 9 It can be seen that there are gaps between the ends of the vertical sections 11 of the respective diffusion beams 10 facing the LED chip 200, so that part of the light emitted from the position directly opposite the LED chip 200 can still be emitted through these gaps, that is, there is still part of the light at the position directly opposite the LED chip 200, and not all the light emitted from the position directly opposite the LED chip 200 will be collected into the diffusion beam 10, resulting in a situation where it is dark at the position directly opposite the LED chip 200 and bright around it.

[0102] In order to make the light homogenization effect of the diffusion beam 10 better, optionally, in an embodiment of the present application, the ends of the vertical sections 11 of the respective diffusion beams 10 close to the LED chip 200 are uniformly arranged in the first region 20, and the first region 20 is located in the surface of the diffusion unit 300 close to the LED chip 200, and the orthographic projection of the first region 20 on the surface of the substrate 100 at least partially overlaps with the orthographic projection of the LED chip 200 on the surface of the substrate 100. Specifically, as shown in Figure 9 shown, the first region is the white square region 20 marked in Figure 9 When the first region is not limited to the square shown in Figure 9 it can also be circular or polygonal. As can be seen from Figure 9 the ends of the vertical sections 11 of the respective diffusion beams 10 close to the LED chip 200 are uniformly arranged in the first region 20 and are arranged closely adjacent to each other, so that the vertical sections 11 of the respective diffusion beams 10 uniformly collect the light emitted from the position directly opposite the LED chip 200.

[0103] Furthermore, in an embodiment of the present application, the ends of the bent sections 12 of the respective diffusion beams 10 away from the LED chip 200 are uniformly arranged in the second region 30, and the second region 30 is located in the surface of the diffusion unit 300 facing away from the LED chip 200, and the orthographic projection of the second region 30 on the surface of the substrate 100 at least partially does not overlap with the orthographic projection of the LED chip 200 on the surface of the substrate 100. Specifically, as shown in Figure 10 shown, the second region 30 is the white square frame region 30 marked in Figure 10 When the second region is not limited to the square frame shape shown in Figure 10 it can also be circular or polygonal. As can be seen from Figure 10It can be seen that the ends of the bent segments 12 of the diffusion beams 10 away from the LED chip are evenly arranged in the second region 30 and are also closely adjacent to each other, so that the bent segments 12 of the diffusion beams 10 uniformly shift the light collected by their corresponding vertical segments 11 to the side edges around the LED chip 200, thereby obtaining a better light homogenization effect.

[0104] Optionally, in another embodiment of the present application, as Figure 11 shown, both the main body portion 321 and the bifurcated portion 322 of the second diffusing portion 320 are filled with a diffusing film material. The bifurcated portion 322 includes an inner side edge and an outer side edge. The outer side edge of the bifurcated portion 322 surrounds the inner side edge of the bifurcated portion 322, and the bifurcation angle of the outer side edge of the bifurcated portion 322 is not less than a first preset angle, so that total internal reflection occurs when light enters the first diffusing portion 310 from the bifurcated portion 322 through its outer side edge.

[0105] Referring to Figure 11 shown, the bifurcation angle of the outer side edge of the bifurcated portion 322 is α, the refractive index of the first diffusing portion 310 is n1, and the refractive index of the second diffusing portion 320 is n2. Then, the bifurcation angle of the outer side edge of the bifurcated portion 322 needs to satisfy the following condition:

[0106] α≥180°-2 arcsin(n1 / n2) (1)

[0107] That is, the first preset angle is equal to 180°-2 arcsin(n1 / n2), so that total internal reflection can occur when light enters the first diffusing portion 310 from the bifurcated portion 322 through its outer side edge.

[0108] It should be noted that among the light rays emitted from the position directly opposite to the LED chip 200, only the light rays with an incident angle greater than the total internal reflection critical angle can undergo total internal reflection in the main body portion 321 and the bifurcated portion 322. Therefore, in this embodiment, even if the orthographic projection of the first end face of the main body portion 321 on the surface of the substrate 100 covers the orthographic projection of the LED chip 200 on the surface of the substrate 100, among the light rays emitted from the position directly opposite to the LED chip 200, there are still some light rays whose incident angles do not satisfy the total internal reflection condition and are emitted from the position directly opposite to the LED chip 200. For example, referring to Figure 11 shown, the light rays emitted from the position directly opposite to the LED chip 200 along the first direction can be directly emitted, and the light rays emitted from the position directly opposite to the LED chip 200 that intersect with the first direction but still do not satisfy the total internal reflection condition can also be directly emitted, so that the situation where the position directly opposite to the LED chip is dark and the surrounding is bright will not occur due to the main body portion 321 and the bifurcated portion 322 shifting all the light rays emitted from the position directly opposite to the LED chip 200 in the direction parallel to the surface of the substrate.

[0109] It can be understood that, as Figure 11As shown, the forking angle β of the inner side of the forking portion 322 may also be not less than the first preset angle, so that total internal reflection also occurs when light enters the first diffusion portion 310 from the forking portion 322 through its inner side. However, in order to avoid the situation where the position directly opposite the LED chip is dark and the surrounding is bright, optionally, in an embodiment of the present application, the forking angle β of the inner side of the forking portion 322 is less than the first preset angle, so that when light enters the first diffusion portion 310 from the forking portion 322 through its inner side, both reflection and refraction can occur.

[0110] Considering that in the actual process, a sharp angle as shown in Figure 11 is generally required to have a high precision on the side of the inner side of the forking portion 322 close to the LED chip 200. Therefore, optionally, in another embodiment of the present application, as shown in Figure 12 the side of the inner side of the forking portion 322 close to the LED chip 200 encloses a platform area, as shown by the part marked by the dashed circle in Figure 12 and this platform area is parallel to the surface of the substrate 100. As can be seen from Figure 12 the light incident on the platform area can be normally emitted, thus avoiding the situation where the position directly opposite the LED chip is dark and the surrounding is bright, and the light incident on the side of the forking portion 322 can be offset to the side position of the LED chip.

[0111] Optionally, in yet another embodiment of the present application, the side of the inner side of the forking portion 322 close to the LED chip 200 encloses an arched area, and this arched area can protrude towards the side close to the LED chip 200, as shown by the part marked by the dashed circle in Fig. 13(a), or can protrude towards the side away from the LED chip 200, as shown by the part marked by the dashed circle in Fig. 14(a).

[0112] Fig. 13(b) gives a schematic diagram of the light transmission when the arched area protrudes towards the side close to the LED chip, and Fig. 14(b) gives a schematic diagram of the light transmission when the arched area protrudes towards the side away from the LED chip. From the light transmission optical paths in Fig. 13(b) and Fig. 14(b), it can be seen that the light incident on the arched area can be normally emitted, thus avoiding the situation where the position directly opposite the LED chip is dark and the surrounding is bright, and the light incident on the side of the forking portion 322 can be offset to the side position of the LED chip. By comparing the light transmission optical paths in Fig. 13(b) and Fig. 14(b), it can be seen that when the arched area protrudes towards the side close to the LED chip, it has a diverging effect on the light emitted from the position directly opposite the LED chip, and when the arched area protrudes towards the side away from the LED chip, it has a converging effect on the light emitted from the position directly opposite the LDE chip. Therefore, preferably, the arched area should protrude towards the side close to the LED chip.

[0113] It should be noted that in the actual process, a sharp angle as shown in Figure 11 is generally formed on the side of the inner edge of the bifurcated portion close to the LED chip, and higher precision is required. However, it is relatively easy to form a platform area as shown in Figure 12 or an arched area as shown in Fig. 13(a).

[0114] Optionally, in an embodiment of the present application, as shown in Figure 15 , the diffusion film material of the bifurcated portion 322 includes at least two diffusion film material regions arranged in sequence along the second direction, and the second direction points from the inner edge of the bifurcated portion to the outer edge of the bifurcated portion;

[0115] The at least two diffusion film material regions include a first diffusion film material region 322-1 and a second diffusion film material region 322-2 arranged in sequence along the second direction, and the refractive index of the second diffusion film material region 322-2 is greater than that of the first diffusion film material region 322-1.

[0116] In this embodiment, referring to the light transmission optical path in Figure 15 , it can be seen that the light emitted from the position facing the LED chip 200 enters the first diffusion film material region 322-1 of the bifurcated portion 322 through the main body portion 321. Since the refractive index of the first diffusion film material region 322-1 is greater than that of the first diffusion portion 321, total internal reflection can occur on the inner edge of the first diffusion film material region 322-1. The light after total internal reflection is transmitted to the interface between the first diffusion film material region 322-1 and the second diffusion film material region 322-2. Since the refractive index of the second diffusion film material region 322-2 is greater than that of the first diffusion film material region 322-1, the light refracts at this interface, and the refracted light is then transmitted to the outer edge of the second diffusion film material region 322-2. Since the refractive index of the second diffusion film material region 322-2 is greater than that of the first diffusion portion 321, the light then undergoes total internal reflection on the outer edge of the second diffusion film material region 322-2 and thus exits.

[0117] It should be noted that referring to the light transmission optical path in Figure 15 , it can be seen that for only the first diffusion film material region 322-1 being provided, some light may be emitted in a direction almost parallel to the substrate surface after total internal reflection on the inner edge of the first diffusion film material region 322-1, specifically as shown in Figure 15As shown by the dashed arrows, it can be understood that although this part of the outgoing light is indeed deflected in a direction parallel to the surface of the substrate, the deflection is excessive and is not available for either the display module for display or the backlight. Therefore, in this embodiment, a second diffusive film material region 322-2 is disposed adjacent to the outer side of the first diffusive film material region 322-1, so as to adjust the exit angle of the light exiting from the outer side of the first diffusive film material region 322-1, such that the exit angle of the light exiting from the outer side of the first diffusive film material region 322-1 is deflected in a first direction, so that the light exiting from the position directly opposite the LED chip can be deflected to its side without excessive deflection and waste.

[0118] Based on the above design concept, optionally, in an embodiment of the present application, as Figure 16 shown, the first diffusive film material region 322-1 and the second diffusive film material region 322-2 are alternately arranged in sequence along a second direction. The specific light transmission optical path is as Figure 16 shown. It can be seen that the exit angle of the light exiting from the second diffusive film material region 322-2 is deflected in the first direction compared to the light exiting from the first diffusive film material region 322-1.

[0119] Optionally, in another embodiment of the present application, as Figure 17 shown, the at least two diffusive film material regions include at least three diffusive film material regions arranged in sequence along the second direction, and along the second direction, the refractive indices of the diffusive film material regions increase in sequence. Referring to Figure 17 shown, the at least three diffusive film material regions include a first diffusive film material region 322-1, a second diffusive film material region 322-2, and a third diffusive film material region 322-3. The specific light transmission optical path is as Figure 17 shown. It can be seen that the exit angle of the light exiting from the third diffusive film material region 322-3 is deflected in the first direction compared to the light exiting from the first diffusive film material region 322-1.

[0120] Based on any of the above embodiments, optionally, in an embodiment of the present application, as Figure 2 shown, in the display module, a diffusive unit 300 is disposed on the side of each LED chip 200 facing away from the substrate, that is, all the diffusive units 300 are of an integrally formed structure.

[0121] It should be noted that the multiple LED chips 200 located on the substrate 100 may be arranged in an array. At this time, the LED chips 200 are evenly distributed on the substrate 100, and correspondingly, the diffusive units 300 are also evenly distributed.

[0122] It should also be noted that Figure 2Adjacent diffusion units 300 are separated by solid lines for one-to-one correspondence with the LED chips. In fact, the first diffusion portion of each diffusion unit 300 may be an integrally formed structure, and the second diffusion portion of each diffusion unit 300 is arranged in one-to-one correspondence with the LED chip 200.

[0123] And, if Figure 2 As shown, the display module may further include:

[0124] The light guide plate 500 is located on the side of the diffusion unit 300 away from the substrate 100 . The light guide plate 500 is used to mix the light emitted from the diffusion unit 300 , so that the light intensity distribution is more uniform.

[0125] It should be noted that in the display module of the prior art, Figure 1 As shown, the distance between the Mini LED chip 02 and the light guide plate 04 cannot be too close, otherwise the display panel will have uneven brightness, which is obviously not conducive to further thinning of the display module. In the embodiment of the present application, the diffusion unit 300 is used to replace the distance between the Mini LED chip 02 and the light guide plate 04 in the prior art. The diffusion unit 300 can not only achieve the effect of uniform light, but also make the display module further thinner by setting the thickness of the diffusion unit 300 along the first direction, which is conducive to the lightweight design of the display module.

[0126] In addition, if Figure 2 As shown, the display module may further include: a display panel 600. In this case, the display module is a backlight module, which provides a display light source for the display panel 600. Of course, the display module may also be a self-luminous display module, which is directly used for display.

[0127] like Figure 2 As shown, the display module may further include: a housing 700 to protect the display module.

[0128] Accordingly, the present application also provides a method for preparing a display module, such as Figure 18 As shown, Figure 18 A schematic diagram of a method for preparing a display module provided in an embodiment of the present application is given. Figure 2 As shown in the cross-sectional structure diagram of the display module, it can be seen that the method includes:

[0129] S100: providing a substrate 100;

[0130] S200: forming a plurality of LDE chips 200 on a substrate 100;

[0131] S300: A diffusion unit 300 is formed on a side of at least one LED chip 200 facing away from the substrate 100. The diffusion unit 300 includes a first diffusion portion 310 and a second diffusion portion 320 penetrating the first diffusion portion 310. The refractive index of the second diffusion portion 320 is greater than that of the first diffusion portion 310.

[0132] Wherein, Figure 3 The cross-sectional structure diagram of a part corresponding to one LED chip in the display module manufactured by using the method provided in the embodiment of the present application is given. As Figure 3 shown, the second diffusion portion 320 includes a main body portion 321 and a bifurcated portion 322. The included angle between the extending direction of the main body portion 321 and the extending direction of the bifurcated portion 322 is greater than zero. The height of the main body portion 321 in the first direction is less than the height of the first diffusion portion 310 in the first direction. The first direction is perpendicular to the substrate surface.

[0133] The first end face of the main body portion 321 is located on the surface of the second diffusion portion 320 close to the LED chip 100. The orthographic projection of the first end face of the main body portion 321 on the substrate surface overlaps at least partially with the orthographic projection of the LED chip 200 on the substrate surface.

[0134] It should be noted that, in this embodiment, the main body portion 321 of the second diffusion portion 320 is arranged close to the LED chip side, and the bifurcated portion 322 extends from the side of the main body portion 321 facing away from the LED chip. Since the included angle between the extending direction of the bifurcated portion 322 and the extending direction of the main body portion 321 is greater than zero, and the refractive index of the second diffusion portion 320 is greater than that of the first diffusion portion 310, when light is incident from the second diffusion portion 320 to the first diffusion portion 310, it is equivalent to being incident from an optically denser medium to an optically thinner medium. As long as the incident angle is greater than the total reflection critical angle, total reflection can occur, that is, the light greater than the total reflection incident angle emitted from the LED chip can undergo total reflection within the main body portion and the bifurcated portion.

[0135] It should also be noted that, referring to Figure 3 shown, the main body portion 321 and the bifurcated portion 322 in the second diffusion portion 320 are a continuous integral structure, rather than two spliced structures. Here, the second diffusion portion 320 is divided into the main body portion 321 and the bifurcated portion 322. Specifically, as Figure 3 shown by the dotted line division in the figure, this is a division of the functions and extending directions of these two parts for the convenience of explanation and understanding.

[0136] Since the luminous intensity at the position directly opposite the LED chip 200 is large, while the luminous intensity between adjacent LED chips 200 (i.e., the side position of the LED chip) is small, the display module manufactured using the method provided in the embodiment of the present application uses the main body 321 to collect at least part of the light emitted from the position directly opposite the LED chip, and uses the fork portion 322 to offset this part of the light in a direction parallel to the surface of the substrate, thereby expanding the emission angle of the light emitted by the LED chip, so that the luminous intensity at the position directly opposite the LED chip is equivalent to the luminous intensity between adjacent LED chips, so as to weaken or eliminate the uneven star-shaped phenomenon in the display panel, so that the display brightness of each part of the display panel is more uniform.

[0137] In this embodiment, the angle between the extension direction of the main body 321 and the extension direction of the bifurcated portion 322 in the second diffusion portion 320 is greater than zero. Then, taking the first direction from the surface of the substrate 100 to the LED chip 200 as the reference direction, the angle between the extension direction of the main body 321 and the reference direction is different from the angle between the extension direction of the bifurcated portion 322 and the reference direction. It should be noted that since the first direction is perpendicular to the substrate surface, the reference direction is also perpendicular to the substrate surface and points from the substrate surface to the LED chip, that is, the reference direction is the normal direction of the substrate 100 surface.

[0138] Optionally, the angle between the extension direction of the main body 321 and the reference direction may be zero, that is, the extension direction of the main body 321 is the same as the reference direction. Figure 3 As shown, at this time, the incident angle of more light emitted from the position facing the LED chip 200 can meet the critical angle of total reflection and thus be collected by the main body; optionally, the angle between the extension direction of the main body 321 and the reference direction can also be greater than zero and less than 90 degrees, such as Figure 5 As shown, at this time, the main body 321 can also deviate the collected light in a direction parallel to the substrate surface.

[0139] Optionally, the angle between the extension direction of the bifurcated portion 322 and the reference direction may be greater than zero and less than 90 degrees, such as Figure 3 As shown, at this time, the outgoing light of the fork portion 322 is emitted to the side away from the substrate 100; optionally, the angle between the extension direction of the fork portion 322 and the reference direction can also be greater than 90 degrees and less than 180 degrees. At this time, the outgoing light of the fork portion is emitted to the side facing the substrate 100. A reflective layer can be provided on the side of the diffusion unit 300 close to the LED chip 100 to emit the outgoing light of the fork portion 322 to the side away from the substrate 100, or it can be emitted directly from the side facing the substrate 100, that is, the display module can emit light on both the side facing away from the substrate and the side facing the substrate.

[0140] It should be noted that, in this embodiment, since the included angle between the extending direction of the bifurcated portion 322 and the extending direction of the main body portion 321 is greater than zero, the included angle between the emitted light rays passing through the main body portion 321 and the bifurcated portion 322 and the initial light rays emitted from the LED chip 200 becomes larger compared to the first direction, thereby ensuring that the emitted light rays passing through the main body portion and the bifurcated portion and emitted from the LED chip are offset in a direction parallel to the surface of the substrate.

[0141] Optionally, in an embodiment of the present application, the included angle between the extending direction of the bifurcated portion 322 and the reference direction is greater than zero and less than 90 degrees. At this time, the second end face of the bifurcated portion 322 is located on the surface of the second diffusion portion 320 facing away from the LED chip 200. Then, in order to improve the light homogenization effect of the diffusion unit, it can be set that the orthographic projection of the second end face of the bifurcated portion 322 on the substrate surface and the orthographic projection of the LED chip 200 on the substrate surface are at least partially non-overlapping, so as to further offset the position of the emitted light rays passing through the main body portion 321 and the bifurcated portion 322 and emitted from the LED chip 200 in a direction parallel to the substrate surface while ensuring that the emitted light rays passing through the main body portion 321 and the bifurcated portion 322 and emitted from the LED chip 200 are offset in a direction parallel to the substrate surface, so as to achieve a better light homogenization effect.

[0142] It can be understood that the second end face of the bifurcated portion 322 includes an inner boundary and an outer boundary, and the outer boundary of the second end face of the bifurcated portion surrounds its inner boundary. In this embodiment, the fact that the orthographic projection of the second end face of the bifurcated portion 322 on the substrate surface and the orthographic projection of the LED chip 200 on the substrate surface are at least partially non-overlapping specifically means that the orthographic projection of the outer boundary of the second end face of the bifurcated portion 322 on the substrate surface and the orthographic projection of the LED chip 200 on the substrate surface are at least partially non-overlapping, so as to be able to offset the position of the emitted light rays passing through the main body portion 321 and the bifurcated portion 322 and emitted from the LED chip 200 in a direction parallel to the substrate surface.

[0143] In order to further improve the light homogenization effect of the diffusion unit, optionally, in an embodiment of the present application, the orthographic projection of the first end face of the main body portion 321 on the substrate surface and the orthographic projection of the second end face of the bifurcated portion 322 on the substrate surface both coincide with the center of the orthographic projection of the LED chip 200 on the substrate surface, so that the main body portion 321 can collect the light rays with a relatively high light intensity at the position directly opposite to the LED chip 200 and offset them in a direction parallel to the substrate surface through the bifurcated portion.

[0144] Further, in an embodiment of the present application, the first end face of the main body portion 321 is circular or regular polygon, so that the light emitted from the position directly opposite to the LED chip can be uniformly collected by the main body portion 321; the second end face of the bifurcated portion 322 includes an inner boundary and an outer boundary, and the outer boundary of the second end face of the bifurcated portion 322 surrounds its inner boundary. The figures formed by the outer boundary and the inner boundary of the second end face of the bifurcated portion 322 are both circular or regular polygon, so that the light emitted from the position directly opposite to the LED chip uniformly collected by the main body portion 321 can be uniformly offset to the sides around the LED chip by the bifurcated portion 322, and then a better light homogenization effect can be obtained.

[0145] Considering that in practical applications, the LED chips 200 usually need to be encapsulated. Therefore, as shown in Figure 2 and Figure 3 , after forming a plurality of LED chips and before forming the diffusion unit, the method further includes:

[0146] S210: Encapsulate each LED chip 200 to form an encapsulation layer 400, so that the encapsulation layer 400 covers the LED chip 200.

[0147] It can be seen that in the display module prepared by using the method provided in the embodiment of the present application, by providing a diffusion unit on the side of the LED chip facing away from the substrate, at least part of the light emitted from the position directly opposite to the LED chip is collected by the main body portion in the diffusion unit, and the light collected by the main body portion is offset in the direction parallel to the surface of the substrate by the bifurcated portion in the diffusion unit, so as to enlarge the emission angle of the light emitted by the LED chip, and then make the luminous intensity at the position directly opposite to the LED chip equivalent to the luminous intensity between adjacent LED chips, weaken or eliminate the phenomenon of uneven bright and dark "starry sky" in the display picture, and improve the uniformity of the display brightness of the display panel.

[0148] Optionally, in an embodiment of the present application, as shown in Figure 7 , the second diffusion portion 320 includes a plurality of diffusion beams arranged at intervals. Then, as shown in Figure 19 , the formation process of the diffusion unit 300 includes:

[0149] S10: As shown in FIG. 8(a), form an encapsulation layer 400 on the side of the LED chip 200 facing away from the substrate.

[0150] S20: As shown in FIG. 8(b), coat a first adhesive layer 311 on the side of the encapsulation layer 400 facing away from the substrate 100, and semi-cure the first adhesive layer 311.

[0151] S30: As shown in FIG. 8(c), insert a plurality of diffusion beams 10 through and into the semi-cured first adhesive layer 311, and cure the first adhesive layer 311.

[0152] In step S30, since the diffusion beam 10 is a material wire made of a high refractive index material and has a certain stiffness, the diffusion beam 10 can penetrate and be inserted into the semi-cured first adhesive layer 311.

[0153] S40: As shown in FIGS. 8(d) and 8(e), a second adhesive layer 312 is coated on the side of the first adhesive layer 311 facing away from the substrate 100, and each diffusion beam 10 is pressed in the direction towards the substrate 100, so that each diffusion beam 10 is pressed into a vertical section 11 and a bent section 12. The vertical section 11 is parallel to the first direction, and the angle between the bent section 12 and the first direction is greater than zero.

[0154] Specifically, in step S40, a pressing jig can be used to apply pressure to each diffusion beam 10 in the direction towards the substrate 100 for pressing. Since one end of each diffusion beam 10 close to the LED chip 200 is fixed by the cured first adhesive layer 311, when each diffusion beam 10 is pressed, it is similar to pressing a lever fixed at one end, so that each diffusion beam 10 deforms under the action of pressure and disperses in all directions.

[0155] It should be noted that in step S40, the coating of the second adhesive layer 312 can be carried out first, and then each diffusion beam 10 can be pressed, or each diffusion beam 10 can be pressed first, and then the coating of the second adhesive layer 312 can be carried out. Note that when the coating of the second adhesive layer 312 is carried out first and then each diffusion beam 10 is pressed, the coating thickness of the second adhesive layer 312 cannot exceed the height of the diffusion beam 10 in the first direction, so as to facilitate the pressing of each diffusion beam 10.

[0156] S50: The second adhesive layer 312 is cured to form a diffusion unit 300, that is, the Figure 7 shown structure is obtained.

[0157] Among them, referring to Figure 7 and FIGS. 8(e), the first diffusion part 310 includes a first adhesive layer 311 and a second adhesive layer 312; the main body part 321 of the second diffusion part 320 includes the vertical sections 11 of each diffusion beam 10, the bifurcated part 322 of the second diffusion part 320 includes the bent sections 12 of each diffusion beam 10, and the first end face of the main body part 321 includes the end face of the vertical section 11 of each diffusion beam 10 facing the LED chip 200.

[0158] It should be noted that Figure 9 FIG. Figure 9 shows a bottom view of the diffusion unit corresponding to one LED chip in the display module provided by the embodiment of the present application in the direction away from the substrate. It can be seen fromFigure 9 As shown by the white circles, the first end face of the main body part 321 includes the end faces of the vertical segments 11 of the respective diffusion beams 10 facing the LED chip 200.

[0159] Figure 10 The following gives a top view schematic diagram of the diffusion unit corresponding to one LED chip in the display module provided by the embodiment of the present application along the direction facing the substrate. Figure 10 It can be seen that in this embodiment, the end face of the end of the bent segment 12 of the diffusion beam 10 away from the LED chip 200 is as Figure 10 shown by the white circles. The second end face of the bifurcated part 322 includes the end faces of the bent segments 12 of the respective diffusion beams 10 away from the LED chip.

[0160] It should also be noted that referring to Figure 9 it can be seen that there are gaps between the ends of the vertical segments 11 of the respective diffusion beams 10 facing the LED chip 200, so that part of the light emitted from the position directly opposite the LED chip 200 can still be emitted through these gaps, that is, there is still part of the light at the position directly opposite the LED chip 200, and not all the light emitted from the position directly opposite the LED chip 200 will be collected into the diffusion beam 10, resulting in a situation where it is dark at the position directly opposite the LED chip 200 and bright around it.

[0161] In order to make the light homogenizing effect of the diffusion beam 10 better, optionally, in an embodiment of the present application, the ends of the vertical segments 11 of the respective diffusion beams 10 close to the LED chip 200 are evenly arranged in a first region 20. The first region 20 is located in the surface of the diffusion unit 300 close to the LED chip 200, and the orthographic projection of the first region 20 on the surface of the substrate 100 overlaps at least partially with the orthographic projection of the LED chip 200 on the surface of the substrate 100. Specifically, as Figure 9 shown, the first region is the Figure 9 white square region 20 marked in Figure 9 . When the first region is not limited to the square shown in Figure 9 , it can also be circular or polygonal. It can be seen that the ends of the vertical segments 11 of the respective diffusion beams 10 close to the LED chip 200 are evenly arranged in the first region 20 and are arranged closely adjacent to each other, so that the vertical segments 11 of the respective diffusion beams 10 evenly collect the light emitted from the position directly opposite the LED chip 200.

[0162] Further, in an embodiment of the present application, the ends of the bent segments 12 of each diffusion beam 10, which are away from the LED chip 200, are uniformly arranged in a second region 30. The second region 30 is located within the surface of the diffusion unit 300 facing away from the LED chip 200, and the orthographic projection of the second region 30 on the surface of the substrate 100 and the orthographic projection of the LED chip 200 on the surface of the substrate 100 are at least partially non-overlapping. Specifically, as Figure 10 shown, the second region 30 is the Figure 10 white square-within-a-square region 30 marked in Figure 10 . While the second region is not limited to the square-within-a-square shape shown in Figure 10 , it can also be an annular shape or a polygonal ring shape. As can be seen from Figure 10 , the ends of the bent segments 12 of each diffusion beam 10, which are away from the LED chip, are uniformly arranged in the second region 30 and are also closely adjacent to each other, so that the bent segments 12 of each diffusion beam 10 uniformly shift the light collected by their corresponding vertical segments 11 to the side edges around the LED chip 200, thereby obtaining a better light homogenization effect.

[0163] Optionally, in another embodiment of the present application, as Figure 11 shown, the main body portion 321 and the bifurcated portion 322 of the second diffusion portion 320 can also be filled with a diffusion film material. At this time, the diffusion unit 300 can be formed by using a 3D printing manufacturing process, which will not be elaborated here.

[0164] Based on the same inventive concept, an embodiment of the present application further provides a display device. As Figure 20 shown, the display device 800 includes the display module 900 provided in any of the above embodiments. Among them, the display module 900 can provide a backlight for the display panel 600 or can be directly used for display. Since the display module 900 has been elaborated in detail in the foregoing embodiments, it will not be elaborated here.

[0165] The display device can be any electronic device with a display function, such as a touch display screen, a mobile phone, a tablet computer, a laptop computer, an e-book, or a television, etc.

[0166] In summary, in the display module, the manufacturing method thereof, and the display device provided by the embodiments of the present application, a diffusion unit is disposed on a side of at least one LED chip facing away from the substrate. The diffusion unit includes a first diffusion portion and a second diffusion portion penetrating the first diffusion portion. The second diffusion portion includes a main body portion and a bifurcated portion. In a direction perpendicular to the surface of the substrate, the height of the main body portion is less than the height of the first diffusion portion. Since a first end surface of the main body portion is located on a surface of the second diffusion portion close to the LED chip, and the orthographic projection of the first end surface of the main body portion on the surface of the substrate overlaps at least partially with the orthographic projection of the LED chip on the surface of the substrate, at least part of the light emitted from a position directly opposite to the LED chip can be collected by the main body portion. Also, since the refractive index of the second diffusion portion is greater than that of the first diffusion portion, the light collected by the main body portion can be totally reflected within the main body portion and the bifurcated portion. Moreover, since the included angle between the extending direction of the bifurcated portion and the extending direction of the main body portion is greater than zero, the emission angle of the light emitted from the bifurcated portion is offset in a direction parallel to the surface of the substrate compared with the emission angle of the initial light emitted from the LED chip, that is, the emission angle of the light emitted from the LED chip is enlarged, so that the luminous intensity at a position directly opposite to the LED chip is equivalent to the luminous intensity between adjacent LED chips, thereby reducing or eliminating the phenomenon of uneven bright and dark "starry sky" in the display panel and improving the uniformity of the display brightness of the display panel.

Claims

1. A display module, characterized in that, Comprising: A substrate; A plurality of LED chips located on the substrate; At least one of the LED chips is provided with a diffusion unit on a side facing away from the substrate. The diffusion unit includes a first diffusion portion and a second diffusion portion penetrating the first diffusion portion, and the refractive index of the second diffusion portion is greater than that of the first diffusion portion; The second diffusion portion includes a main body portion and a bifurcated portion. The included angle between the extending direction of the main body portion and the extending direction of the bifurcated portion is greater than zero. The height of the main body portion in a first direction is less than the height of the first diffusion portion in the first direction, and the first direction is perpendicular to the surface of the substrate; The first end face of the main body portion is located on the surface of the second diffusion portion close to the LED chip, and the positive projection of the first end face of the main body portion on the surface of the substrate overlaps at least partially with the positive projection of the LED chip on the surface of the substrate; The function of the main body portion is to collect at least part of the light emitted from the position directly opposite to the LED chip; The function of the bifurcated portion is to offset at least part of the light emitted from the position directly opposite to the LED chip collected by the main body portion in a direction parallel to the surface of the substrate; The bifurcated portion offsetting at least part of the light emitted from the position directly opposite to the LED chip collected by the main body portion in a direction parallel to the surface of the substrate includes: Compared with the initial light emitted from the LED chip, the included angle between the emitted light passing through the main body portion and the bifurcated portion and the first direction becomes larger; And / or, Compared with the initial light emitted from the LED chip, the position of the emitted light passing through the main body portion and the bifurcated portion is offset towards the side position of the LED chip.

2. The display module according to claim 1, wherein The second end face of the bifurcated portion is located on the surface of the second diffusion portion facing away from the LED chip, and the positive projection of the second end face of the bifurcated portion on the surface of the substrate does not overlap at least partially with the positive projection of the LED chip on the surface of the substrate; 3. The display module according to claim 1, wherein The positive projection of the first end face of the main body portion on the surface of the substrate and the positive projection of the second end face of the bifurcated portion on the surface of the substrate both coincide with the center of the positive projection of the LED chip on the surface of the substrate; 4. The display module according to claim 3, wherein The first end face of the main body portion is circular or regular polygon; The second end face of the bifurcated portion includes an inner boundary and an outer boundary. The outer boundary surrounds the inner boundary, and the figures formed by the outer boundary and the inner boundary are both circular or regular polygon; 5. The display module according to claim 2, wherein The second diffusion portion includes a plurality of diffusion beams arranged at intervals. The diffusion beam includes a vertical section and a bent section. The vertical section is parallel to the first direction, and the included angle between the bent section and the first direction is greater than zero; The main body portion includes the vertical sections of each diffusion beam, and the first end face of the main body portion includes the end faces of the vertical sections of each diffusion beam facing the LED chip; The bifurcated portion includes the bent sections of each diffusion beam, and the second end face of the bifurcated portion includes the end faces of the bent sections of each diffusion beam away from the LED chip.

6. The display module according to claim 5, wherein One end of the vertical section of each of the diffusion beams close to the LED chip is uniformly arranged in a first region, the first region is located in the surface of the diffusion unit close to the LED chip, and the orthographic projection of the first region on the substrate surface overlaps at least partially with the orthographic projection of the LED chip on the substrate surface.

7. The display module according to claim 6, wherein One end of the bent section of each of the diffusion beams far from the LED chip is uniformly arranged in a second region, the second region is located in the surface of the diffusion unit facing away from the LED chip, and the orthographic projection of the second region on the substrate surface does not overlap at least partially with the orthographic projection of the LED chip on the substrate surface.

8. The display module according to claim 2, wherein, Both the main body portion and the bifurcated portion are filled with a diffusion film material. The bifurcated portion includes an inner side and an outer side. The outer side of the bifurcated portion surrounds the inner side of the bifurcated portion. The bifurcation angle of the outer side of the bifurcated portion is not less than a first preset angle, so that total reflection occurs when light enters the first diffusion portion from the bifurcated portion through its outer side.

9. The display module according to claim 8, wherein The bifurcation angle of the inner side of the bifurcated portion is less than the first preset angle, so that when light enters the first diffusion portion from the bifurcated portion through its inner side, both reflection and refraction occur.

10. The display module according to claim 8, wherein One side of the inner side of the bifurcated portion close to the LED chip surrounds a platform region, and the platform region is parallel to the substrate surface; Or, One side of the inner side of the bifurcated portion close to the LED chip surrounds an arched region, and the arched region protrudes toward the side close to the LED chip.

11. The display module according to claim 8, wherein The diffusion film material of the bifurcated portion includes at least two diffusion film material regions arranged in sequence in a second direction, and the second direction points from the inner side of the bifurcated portion to the outer side of the bifurcated portion; The at least two diffusion film material regions include a first diffusion film material region and a second diffusion film material region arranged in sequence in the second direction, and the refractive index of the second diffusion film material region is greater than the refractive index of the first diffusion film material region.

12. The display module according to claim 11, wherein The first diffusion film material region and the second diffusion film material region are alternately arranged in sequence in the second direction.

13. The display module according to claim 11, wherein The at least two diffusion film material regions include at least three diffusion film material regions arranged in sequence in the second direction, and along the second direction, the refractive indices of the diffusion film material regions increase in sequence.

14. The display module according to claim 1, wherein One side of each LED chip facing away from the substrate is provided with the diffusion unit, and all the diffusion units are of an integrally formed structure.

15. The display module according to claim 1, wherein The display module further includes: a packaging layer located between the LED chip and the diffusion unit, the packaging layer covers the LED chip, and the refractive index of the first diffusion portion is not less than the refractive index of the packaging layer.

16. A method for preparing a display module, characterized in that, Including: Providing a substrate; Forming a plurality of LED chips on the substrate; Forming a diffusion unit on one side of at least one of the LED chips facing away from the substrate, the diffusion unit includes a first diffusion portion and a second diffusion portion penetrating through the first diffusion portion, and the refractive index of the second diffusion portion is greater than the refractive index of the first diffusion portion; The second diffusion portion includes a main body portion and a bifurcated portion, the angle between the extension direction of the main body portion and the extension direction of the bifurcated portion is greater than zero, the height of the main body portion along a first direction is less than the height of the first diffusion portion along the first direction, and the first direction is perpendicular to the substrate surface; The first end surface of the main body is located on the surface of the second diffusion part close to the LED chip, and the orthographic projection of the first end surface of the main body on the substrate surface at least partially overlaps with the orthographic projection of the LED chip on the substrate surface; The function of the main body is to collect at least part of the light emitted from the position directly facing the LED chip; The function of the bifurcated portion is to deflect at least part of the light emitted from the position opposite to the LED chip collected by the main body toward a direction parallel to the surface of the substrate; The forked portion offsets at least part of the light emitted from the LED chip facing the main portion and collected by the main portion in a direction parallel to the surface of the substrate, including: Compared with the initial light emitted from the LED chip, the angle between the light emitted from the LED chip and the first direction becomes larger. and / or, Compared with the initial light emitted from the LED chip, the position of the light emitted from the LED chip and passing through the main body and the bifurcated portion is offset toward the side of the LED chip.

17. The method according to claim 16, wherein The second diffusion portion includes a plurality of diffusion beams arranged at intervals, and the formation process of the diffusion unit includes: forming a packaging layer on a side of the LED chip away from the substrate; Coating a first adhesive layer on a side of the encapsulation layer away from the substrate, and semi-curing the first adhesive layer; Inserting a plurality of diffusion beams through the semi-cured first adhesive layer, and curing the first adhesive layer; A second adhesive layer is applied on a side of the first adhesive layer facing away from the substrate, and each of the diffusion beams is pressed toward the substrate, so that each of the diffusion beams is pressed into a vertical section and a bent section, the vertical section is parallel to the first direction, and the angle between the bent section and the first direction is greater than zero; curing the second adhesive layer to form the diffusion unit; Among them, the first diffusion part includes the first glue layer and the second glue layer; the main body of the second diffusion part includes the vertical segments of each of the diffusion beams, the fork portion of the second diffusion part includes the bending segments of each of the diffusion beams, and the first end face of the main body includes the end face of the vertical segments of each of the diffusion beams facing the LED chip.

18. A display device, characterized in that, A display module comprising any one of claims 1-15.

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