CN216647021U

CN216647021U - Backlight source structure, display module and electronic equipment

Info

Publication number: CN216647021U
Application number: CN202122354719.3U
Authority: CN
Inventors: 袁高; 刘湘绮
Original assignee: Honor Device Co Ltd
Current assignee: Honor Device Co Ltd
Priority date: 2021-09-27
Filing date: 2021-09-27
Publication date: 2022-05-31
Anticipated expiration: 2031-09-27

Abstract

The application relates to the technical field of display, and discloses a backlight source structure, a display module and an electronic device. The backlight source structure provided by the embodiment of the application is provided with a corresponding two-dimensional grating on the light-emitting surface of each light-emitting unit; the two-dimensional grating comprises a plurality of light through holes which are communicated with the first surface and the second surface of the two-dimensional grating; the first surface is a surface opposite to the light-emitting surface of the light-emitting unit, and the second surface is opposite to the first surface. In the backlight structure provided by the embodiment of the application, light emitted by the light emitting unit can be diffracted through the plurality of light through holes on the two-dimensional grating, so that the light emitted by the light emitting unit finally forms uniform light, and the uniformity of the brightness of a plurality of pixel points in the light emitting display layer area corresponding to a single light emitting unit can be effectively improved.

Description

Backlight source structure, display module and electronic equipment

Technical Field

The application relates to the technical field of display, in particular to a backlight source structure, a display module and an electronic device.

Background

Light Emitting Diodes (LEDs) are semiconductor electronic components that convert electrical energy into Light energy, and are widely used in the fields of lighting, display devices, signal lamps, backlights, toys, etc. because they have the characteristics of small size, long service life, rich and colorful colors, and low energy consumption.

With the increasing requirements of the electronic display device market on ultra-thin, high screen ratio and high color saturation, the Mini LED (LED with a chip size between 50 and 200 μm) device is widely applied to the backlight structure of the electronic display device. For example, fig. 1 shows a schematic structural diagram of a display module 002 in an electronic device 001, and as shown in fig. 1, the display module 002 of the electronic device 001 may include a light-emitting display layer 100 and a backlight structure 200, where the backlight structure 200 may employ a Mini LED chip array, where the Mini LED chip array includes a plurality of Mini LED chips distributed in n rows and m columns.

However, because the Mini LED chip belongs to a Lambertian light source, the luminous intensity distribution rule is that the luminous intensity gradually weakens from the center to the periphery. Therefore, the uniformity of the brightness of the plurality of pixels in the light-emitting display layer 100 corresponding to a single light-emitting surface is poor.

SUMMERY OF THE UTILITY MODEL

In order to solve the above problem, a first aspect of the embodiments of the present application provides a backlight structure, including: the device comprises a substrate, a plurality of light-emitting units and a plurality of two-dimensional gratings;

the light-emitting units are positioned on the substrate, and a corresponding two-dimensional grating is arranged on a light-emitting surface of each light-emitting unit;

the two-dimensional grating comprises a plurality of light through holes which are communicated with the first surface and the second surface of the two-dimensional grating; the first surface is a surface opposite to a light emitting surface of the light emitting unit, and the second surface is opposite to the first surface.

It can be understood that, in the embodiment of the present application, the first surface is a surface connected to the light emitting surface of the light emitting unit.

In a practical manner of the first aspect, the light emitting unit is a Mini LED chip.

In the embodiment of the present application, the light emitting direction of the Mini LED chip may be defined as the thickness direction along the two-dimensional grating, and the light emitting surface of the Mini LED chip is the upper surface of the Mini LED chip.

It can be understood that in the embodiment of the present application, the number of the two-dimensional gratings is the same as that of the Mini LED chips. And light rays emitted by each Mini LED chip can be diffracted after passing through each light through hole in the two-dimensional grating.

The backlight source structure that this application embodiment provided can change the light that the Mini LED chip sent all around diffusion type through above-mentioned two-dimensional grating into through the diffraction light that uses a plurality of clear holes as the evenly distributed of array, and make the light that the Mini LED chip sent finally form comparatively even light, can effectively improve the homogeneity of the luminance of a plurality of pixel points in the luminous display layer region that single Mini LED chip corresponds.

In a practical manner of the first aspect, the plurality of light passing holes on the two-dimensional grating are identical in shape and size.

It is understood that, in the embodiment of the present application, the cross-sectional dimension of each light through hole on the two-dimensional grating parallel to the substrate 201 may be in the range of 100-1000 nm. It will be appreciated that, according to the principle of light diffraction, when the cross-sectional size of the hole is close to the wavelength of the incident light, the incident light can be significantly diffracted through the hole.

In a first implementable manner, the sizes of the plurality of light-passing holes on the two-dimensional grating gradually increase along a direction in which a central point of the light-emitting surface of the light-emitting unit points to an edge of the light-emitting surface of the light-emitting unit.

It can be understood that in the embodiment of the present application, the larger the size of the light through hole is, the larger the light flux is; the greater the luminous flux, the greater the light intensity. Therefore, the arrangement scheme can enable the luminous flux of each light through hole to be gradually reduced along the direction that the central point of the light-emitting surface of the Mini LED chip points to the edge of the light-emitting surface of the Mini LED chip, so that the light intensity of the central area of the Mini LED chip is suppressed, and the light passing through the two-dimensional grating is more uniform.

In a first practical manner, fillers are disposed in the light-passing holes on the two-dimensional grating, and the transparency of the fillers in the light-passing holes gradually increases along a direction in which a center point of the light-emitting surface of the light-emitting unit points to an edge of the light-emitting surface of the light-emitting unit.

It can be understood that, in the embodiment of the present application, the setting of the two-dimensional grating is such that the transparency of each light through hole gradually increases along the direction from the central point of the light emitting surface of the Mini LED chip to the edge of the light emitting surface of the Mini LED chip, so that the luminous flux of each light through hole gradually decreases along the direction from the central point of the light emitting surface of the Mini LED chip to the edge of the light emitting surface of the Mini LED chip, thereby suppressing the light intensity in the central area of the Mini LED chip, and making the light passing through the two-dimensional grating more uniform.

In a first practical aspect of the first aspect, the thickness of the filler gradually decreases along a direction from a center point of the light emitting surface of the light emitting unit to an edge of the light emitting surface of the light emitting unit.

It can be understood that in the embodiment of the present application, the transparency of the filler in each light-passing hole can be controlled by controlling the thickness of the filler, so that the transparency of each light-passing hole in the two-dimensional grating gradually increases along a direction in which the central point of the light-emitting surface of the Mini LED chip points to the edge of the light-emitting surface of the Mini LED chip.

In a practical aspect of the first aspect, the filler and the two-dimensional grating are made of the same material.

It can be understood that when the material of the filler is the same as that of the two-dimensional grating, the filler and the two-dimensional grating can be simultaneously prepared, and the preparation process is simplified.

In a first aspect, the filler and the two-dimensional grating are integrally formed into a unitary structure.

In a first practical manner, the distribution density of the plurality of light-passing holes on the two-dimensional grating gradually increases along a direction in which a center point of the light-emitting surface of the light-emitting unit points to an edge of the light-emitting surface of the light-emitting unit.

It can be understood that, in the embodiment of the present application, the distribution density of the light through holes may be implemented in a manner that the distance between adjacent light through holes of the two-dimensional grating gradually decreases along a direction in which the central point of the light emitting surface of the Mini LED chip points to the edge of the light emitting surface of the Mini LED chip; therefore, the light through holes in the edge area of the two-dimensional grating are more dense relative to the light through holes in the central area, the luminous flux in the central area of the two-dimensional grating can be reduced, the luminous flux in the edge area of the two-dimensional grating can be increased, and the light passing through the two-dimensional grating is more uniform.

In a first aspect, the light emitting device further includes an encapsulation adhesive layer, where the encapsulation adhesive layer is disposed above the plurality of two-dimensional gratings and encapsulates the plurality of light emitting units and the plurality of two-dimensional gratings.

In a first aspect, the package structure further includes a micro-structure layer, where the micro-structure layer is disposed on the light-emitting surface of the package adhesive layer;

the micro-structure layer comprises a plurality of protruding structures arranged on the light-emitting surface of the packaging adhesive layer.

It can be understood that, in the embodiment of the present application, the micro-structure layer may include an uneven shape formed on an upper surface of the encapsulation adhesive layer, i.e., a surface facing away from the light emitting surface of the light emitting unit, so that the upper surface of the encapsulation adhesive is a rough surface. Specifically, a plurality of protruding structures may be formed on the encapsulation adhesive layer to form a microstructure layer, wherein the protruding structures may be in the shape of a cone, a cylinder, a hemispherical protrusion, an irregular protrusion, or the like.

The micro-structural layer can realize diffuse reflection of an interference dot matrix generated by diffraction light of the two-dimensional grating into a uniform surface light source. Therefore, the uniformity of the brightness of each pixel point in the light-emitting display layer above the backlight source structure is effectively improved.

In a first aspect, which can be implemented, the backlight structure includes a reflective layer,

the reflecting layer is arranged above the gaps of the adjacent light-emitting units in the plurality of light-emitting units;

at least a first partial area of the reflecting layer is arranged on the light-emitting surface of one of the adjacent light-emitting units, and at least a second partial area of the reflecting layer is arranged on the light-emitting surface of the other light-emitting unit.

It can be understood that, in the embodiment of the present application, the reflective layer may be made of a material having a strong reflective effect. Wherein, the reflective layer can cover the whole gap between two adjacent Mini LED chips. The reflective layer 208 can totally reflect the emergent light from the side of any one of the two adjacent Mini LED chips onto the other Mini LED chip, so that the light mixing effect between the chips can be effectively reduced.

In a first implementable manner of the first aspect, the reflection layer and the two-dimensional grating are disposed in the same layer in the light exit direction of the light emitting unit. In some embodiments, the reflective layer and the two-dimensional grating may be the same thickness. The light emitting direction of the Mini LED chip may be along the thickness direction of the two-dimensional grating.

In a first aspect, the reflective layer is made of the same material as the two-dimensional grating, and the reflective layer and the two-dimensional grating are integrally formed.

In some embodiments, the reflective layer and the two-dimensional grating may be made of the same material, for example, both may be made of a strong reflective metal material such as gold, silver, or aluminum, which can ensure that the emergent light from the side of any one of the two adjacent Mini LED chips is totally reflected onto the other Mini LED chip, thereby effectively reducing the light mixing effect between the chips.

In some embodiments, the reflective layer and the plurality of two-dimensional gratings may be integrally formed, which may effectively simplify the manufacturing process.

In a first aspect, the backlight structure further includes a diffusion layer, and the diffusion layer is disposed on a side of the microstructure layer facing away from the encapsulation adhesive layer.

It is understood that, in some embodiments, the diffusion layer may be disposed on the upper surface of the microstructure layer, and the diffusion layer and the microstructure layer are stacked in the light emitting direction of the Mini LED chip.

In some embodiments, the diffusion layer and the microstructure layer may have a predetermined spacing therebetween, that is, the diffusion layer is disposed on the upper surface of the microstructure layer by a fixing mechanism.

In the embodiment of the application, the diffusion layer is arranged so that light passing through the microstructure layer can be further diffused through the diffusion layer. The number of the diffusion layers in the backlight source structure provided in the embodiment of the present application may be one or multiple. The embodiments of the present application are not limited herein. In some embodiments, in embodiments where no micro-structured layer is provided, a diffusion layer may also be provided on the upper surface of the encapsulant layer.

A second aspect of the embodiments of the present application provides a display module, including a light-emitting display layer and the backlight structure.

A third aspect of the embodiments of the present application provides an electronic device, including the display module.

Drawings

FIG. 1 illustrates a schematic structural view of a display module, according to some embodiments of the present application;

FIG. 2 illustrates a schematic diagram of a backlight configuration, according to some embodiments of the present disclosure;

FIG. 3 illustrates a schematic diagram of a backlight configuration with a two-dimensional grating, according to some embodiments of the present disclosure;

FIG. 4 is a schematic diagram illustrating the propagation of light from a Mini LED chip in a backlight configuration, according to some embodiments of the present disclosure;

FIG. 5 is a schematic view of (a), (b), (c), and (d) of the shape of a clear hole, respectively, according to some embodiments of the present application;

FIG. 6 illustrates a schematic diagram of a size distribution of light passing holes on a two-dimensional grating, according to some embodiments of the present application;

FIG. 7a shows a schematic diagram of a backlight configuration, according to some embodiments of the present application;

FIG. 7b shows a schematic diagram of a backlight configuration, according to some embodiments of the present application;

FIG. 8 illustrates a schematic diagram of a backlight structure with an encapsulant layer, according to some embodiments of the present disclosure;

FIG. 9 illustrates a schematic diagram of a backlight construction having a microstructured layer, according to some embodiments of the present disclosure;

FIG. 10 illustrates a schematic diagram of a backlight construction having a microstructured layer, according to some embodiments of the present disclosure;

FIG. 11a shows a schematic representation of the reflection of light by a highly reflective layer in a backlight construction, according to some embodiments of the present disclosure;

FIG. 11b shows a schematic diagram of a backlight configuration, according to some embodiments of the present application;

FIG. 11c shows a schematic diagram of a backlight configuration, according to some embodiments of the present application;

fig. 12 illustrates a schematic diagram of a backlight structure with a diffuser layer, according to some embodiments of the present disclosure.

Detailed Description

The following description of the embodiments of the present application is provided by way of specific examples, and other advantages and effects of the present application will be readily apparent to those skilled in the art from the disclosure herein. While the description of the present application will be presented in conjunction with certain embodiments, this is not intended to limit the features of this application to that embodiment. On the contrary, the application of the present disclosure with reference to the embodiments is intended to cover alternatives or modifications as may be extended based on the claims of the present disclosure. In the following description, numerous specific details are included to provide a thorough understanding of the present application. The present application may be practiced without these particulars. Moreover, some of the specific details have been omitted from the description in order to avoid obscuring, or obscuring, the focus of the present application. It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict.

It should be noted that in this specification, like reference numerals and letters refer to like items in the following drawings, and thus, once an item is defined in one drawing, it need not be further defined and explained in subsequent drawings. In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

To make the objects, technical solutions and advantages of the present application more clear, embodiments of the present application will be described in further detail below with reference to the accompanying drawings.

As mentioned above, the Mini LED chip belongs to a lambertian light source, and therefore, the light intensity distribution curve is I (θ, Φ) ═ I0cosm θ, where θ is the light intensity angle, i.e. the angle between the light direction and the central light direction of the Mini LED chip, I is the light intensity at the light intensity angle θ, and m is determined by the half light intensity angle θ 1/2 of the Mini LED chip, i.e. m ═ ln2/ln (cos θ 1/2). From the above equation, the smaller the half intensity angle θ 1/2 is, the larger the value of m is, and the larger the intensity is when the intensity angle is θ, that is, the luminous intensity distribution rule of the Mini LED chip is that the luminous intensity gradually weakens from the center to the periphery. Therefore, the uniformity of the brightness of a plurality of pixel points in the corresponding light-emitting display layer on the single Mini LED chip is poor.

In order to solve the above problem, the present application provides a backlight structure, which performs light uniformization by disposing a plurality of diffusion layers above a Mini LED chip. For example, as shown in fig. 2, the backlight structure 200 provided by the present application may include a substrate 201, a Mini LED chip array, an encapsulation adhesive layer 203, a first diffusion layer 205, a second diffusion layer 206, and a third diffusion layer 207.

The Mini LED chip array may include a plurality of Mini LED chips 202, and the plurality of Mini LED chips 202 may be distributed on the substrate 201 in n rows and m columns; the packaging adhesive layer 203 is arranged above the substrate 201 and coats the Mini LED chip array; the first diffusion layer 205, the second diffusion layer 206 and the third diffusion layer 207 are sequentially stacked above the encapsulation adhesive layer 203.

The light emitted by each Mini LED chip 202 is dispersed for the first time by the first diffusion layer 205, dispersed for the second time by the second diffusion layer 206, and dispersed for the third time by the third diffusion layer 207 to form uniform light.

However, the above-mentioned way of homogenizing light by means of a plurality of diffusion layers leads to an increase in the thickness of the overall backlight structure. To solve this problem, embodiments of the present application provide another backlight structure. Fig. 3 is a schematic view of a backlight structure 200 according to an embodiment of the disclosure.

As shown in fig. 3, the backlight structure 200 provided in the embodiment of the present application may include a substrate 201, a Mini LED chip array, and a plurality of two-dimensional gratings 204; the Mini LED chip array may include a plurality of Mini LED chips 202, the Mini LED chips 202 may be distributed in n rows and m columns, and the Mini LED chips 202 are all disposed on the substrate 201; each two-dimensional grating 204 of the plurality of two-dimensional gratings 204 is correspondingly disposed on the upper surface of the light-emitting surface of the Mini LED chip 202, wherein each two-dimensional grating 204 is provided with a plurality of light-passing holes 2040. The extending direction of the central axis of the light through hole is consistent with the light emitting direction of the Mini LED chip 202.

In this embodiment, the light emitting direction of the Mini LED chip 202 may be defined as the thickness direction along the two-dimensional grating 204, and the light emitting surface of the Mini LED chip 202 is the upper surface of the Mini LED chip 202.

It can be understood that in the embodiment of the present application, the number of the two-dimensional gratings 204 is the same as that of the Mini LED chips 202.

The light emitted by each Mini LED chip 202 is diffracted through each light-passing hole 2040 in the two-dimensional grating 204, and due to the diffraction effect, the diffracted light is normally distributed, that is, the diffracted light passing through each light-passing hole 2040 on the two-dimensional grating 204 is mainly central light intensity, and the light intensities at the two sides are distributed in a symmetrical and gradually decreasing trend by taking the central light intensity as an axis. It is understood that since the diffracted light passing through each light passing hole 2040 is normally distributed as described above, the distribution of the diffracted light passing through each light passing hole 2040 is uniform. The backlight source structure 200 provided in the embodiment of the application can convert the light emitted by the Mini LED chip 202 into the diffraction light which is uniformly distributed by using the plurality of light through holes 2040 as an array through the two-dimensional grating 2040, so that the light emitted by the Mini LED chip 202 finally forms uniform light, and the uniformity of the brightness of the plurality of pixels in the light-emitting display layer region corresponding to the single Mini LED chip 202 can be effectively improved.

For example, as shown in fig. 4, a light ray i1 emitted by the Mini LED chip 202 is diffracted by the first light passing hole 2041 of the two-dimensional grating 204 to generate a plurality of diffracted light rays having different light ray directions from the light ray i1, which are respectively a diffracted light ray i11, a diffracted light ray i12 and a diffracted light ray i 13; another beam of light i2 emitted by the Mini LED chip 202 is diffracted through the second light passing hole 2042 of the two-dimensional grating 204 to generate a plurality of diffracted lights with different light directions from the light i2, which are respectively a diffracted light i21, a diffracted light i22 and a diffracted light i23, wherein the diffracted light i12 and the diffracted light i21 are crossed and overlapped to generate interference to form a point i01, and the diffracted light i13 and the diffracted light i22 are crossed and overlapped to generate interference to form a point i 02.

It should be understood that the above description is only based on the light passing through two light passing holes 2040 of the two-dimensional grating 204 in one Mini LED chip 202, and in the embodiment of the present application, the light passing through the light passing holes 2040 of the two-dimensional grating 204 in a single Mini LED chip 202 may interfere with each other at different positions to form a two-dimensional light lattice.

In the present embodiment, the shape of the light passing hole 2040 of the two-dimensional grating 204 may be various, for example, in some embodiments, as shown in fig. 5 (a), the cross-sectional shape of the light passing hole 2040 parallel to the substrate 201 is a circle. In some embodiments, as shown in fig. 5 (b), the cross-sectional shape of the light passing hole 2040 parallel to the substrate 201 is rectangular; in some embodiments, the cross-sectional shape of the light passing hole 2040 parallel to the substrate 201 may be a star shape as shown in fig. 5 (c), and in some embodiments, the shape of the light passing hole 2040 may be an ellipse as shown in fig. 5 (d). Specifically, the cross-sectional shape of the light passing hole 2040 parallel to the base 201 may be a triangle, a parallelogram, or other various shapes. The embodiments of the present application are not limited herein.

In the embodiment of the present application, the cross-sectional dimension of each light passing hole 2040 on the two-dimensional grating 204 parallel to the substrate 201 may be in the range of 100 nm and 1000 nm. It can be understood that according to the principle of light diffraction, when the cross-sectional size of the hole is close to the wavelength of the incident light, the incident light can be significantly diffracted by the hole, and therefore, the size of the light passing hole 2040 can achieve that the light emitted by the Mini LED chip 202 is significantly diffracted by each light passing hole 2040 in the two-dimensional grating 204. The cross-sectional dimension is any physical dimension capable of indicating the size of the cross-section area of the light-passing hole 2040, such as a diameter and a length; specifically, when the light passing hole 2040 is circular, the diameter of the light passing hole 2040 may be set to be in the range of 100-1000 nm; when the shape of the light passing hole 2040 is rectangular, the length and the width of the light passing hole 2040 may be set to be within the range of 100-1000 nm.

In some embodiments, each light passing hole 2040 in the two-dimensional grating 204 may have the same shape and size, and the spacing between any two adjacent light passing holes 2040 may be in the range of 100-1000 nm.

In the embodiment of the present application, the light intensity in the central region of the Mini LED chip 202 may be suppressed, so that the light emitted by the Mini LED chip 202 may be more uniform when finally reaching the light emitting display layer. The step of suppressing the light intensity in the central area of the Mini LED chip 202 may be to decrease the light intensity in the central area of the Mini LED chip 202 and increase the light intensity in the edge area of the Mini LED chip 202.

There are various embodiments for suppressing the light intensity in the central region of the Mini LED chip 202, and some of them are described as follows:

in an implementable scheme, as shown in fig. 6, the size of each light-passing hole 2040 of the two-dimensional grating 204 may be set to gradually increase along a direction in which the central point of the light-emitting surface of the Mini LED chip 202 points to the edge of the light-emitting surface of the Mini LED chip 202; or the size of each light-passing hole 2040 of the two-dimensional grating 204 gradually increases along the direction from the center point of the light-emitting surface of the Mini LED chip 202 to the edge of the light-emitting surface of the Mini LED chip 202. For example, as shown in fig. 6, the two-dimensional grating 204 has a central light-passing hole L1, an edge light-passing hole L3, and a middle light-passing hole L2 between the central light-passing hole L1 and the edge light-passing hole L3, wherein the diameters of the central light-passing hole L1, the middle light-passing hole L2, and the edge light-passing hole L3 are gradually increased.

It is understood that the larger the size of the light passing hole 2040, the larger the light flux; the greater the luminous flux, the greater the light intensity. Therefore, the arrangement scheme can gradually reduce the luminous flux of each light-passing hole 2040 along the direction from the central point of the light-emitting surface of the Mini LED chip 202 to the edge of the light-emitting surface of the Mini LED chip 202, so as to suppress the light intensity in the central area of the Mini LED chip 202, and make the light passing through the two-dimensional grating 204 more uniform.

In the second implementable scheme, a trend that the transparency of each light-passing hole 2040 in the two-dimensional grating 204 gradually increases along a direction in which the central point of the light-emitting surface of the Mini LED chip 202 points to the edge of the light-emitting surface of the Mini LED chip 202 may be set, so that the luminous flux of each light-passing hole 2040 gradually decreases along a direction in which the central point of the light-emitting surface of the Mini LED chip 202 points to the edge of the light-emitting surface of the Mini LED chip 202, thereby achieving suppression of the light intensity of the central area of the Mini LED chip 202, and making the light passing through the two-dimensional grating 204 more uniform.

The manner of adjusting and controlling the transparency of each light-passing hole 2040 in the two-dimensional grating 204 may be to fill fillers with different thicknesses in the light-passing hole 2040, for example, to fill metal layers with different thicknesses and with set transparency, specifically, the filling thickness of the metal layer in each light-passing hole 2040 may gradually decrease along a direction from the central point of the light-emitting surface of the Mini LED chip 202 to the edge of the light-emitting surface of the Mini LED chip 202, so that the transparency of each light-passing hole 2040 gradually increases along a direction from the central point of the light-emitting surface of the Mini LED chip 202 to the edge of the light-emitting surface of the Mini LED chip 202. For example, as shown in fig. 7a, the two-dimensional grating 204 has a central light-passing hole L1, an edge light-passing hole L3, and a middle light-passing hole L2 between the central light-passing hole L1 and the edge light-passing hole L3, wherein the filling thickness of the inner metal layer of the central light-passing hole L1, the middle light-passing hole L2, and the edge light-passing hole L3 gradually decreases.

It is understood that, in the embodiment of the present application, the material of the metal layer may include, but is not limited to, a metal material such as gold, silver, aluminum, and the like.

In some embodiments, the transparency of the light passing hole 2040 closest to the central point of the light emitting surface of the Mini LED chip 202 may be set within a range of 0 to 50%, and the transparency of each light passing hole 2040 gradually increases along a direction from the central point of the light emitting surface of the Mini LED chip 202 to the edge of the light emitting surface of the Mini LED chip 202, wherein the transparency of the outermost light passing hole 2040 on the two-dimensional grating may be within a range of 70 to 100%. Wherein, if the transparency of the light passing hole 2040 is set to be within the range of 0-50%, the thickness of the metal layer in the light passing hole 2040 can be within the range of 60nm-120 nm; if the transparency of the light passing hole 2040 is set to be in the range of 70 to 100%, the thickness of the metal layer in the light passing hole 2040 may be in the range of 0 to 60 nm.

In some embodiments, the manner of adjusting the transparency of each light passing hole 2040 in the two-dimensional grating 204 may be to fill the light passing holes 2040 with fillers of different transparencies and with the same thickness, for example, each light passing hole 2040 may be filled with materials of different materials to achieve different transparencies.

It can be understood that the above-mentioned manners of adjusting and controlling the transparency of each light-passing hole 2040 in the two-dimensional grating 204 can also be combined; for example, the thickness of the filler in the light holes in the two-dimensional grating 204 may be different, and the material of the filler in the other light holes may be different, so that the transparency of each light hole 2040 in the two-dimensional grating 204 gradually increases along the direction from the central point of the light exit surface of the Mini LED chip 202 to the edge of the light exit surface of the Mini LED chip 202.

In some embodiments, as shown in fig. 7b, the filler may be made of the same material as the two-dimensional grating 204, and the filling thickness of the filler in the plurality of light passing holes 2040 may gradually decrease along a direction in which the central point of the light emitting surface of the Mini LED chip 202 points to the edge of the light emitting surface of the Mini LED chip 202, so that the transparency of each light passing hole 2040 gradually increases along a direction in which the central point of the light emitting surface of the Mini LED chip 202 points to the edge of the light emitting surface of the Mini LED chip 202. Wherein, in some embodiments, the filler may be filled after the two-dimensional grating 204 is prepared; in some embodiments, the filler may be fabricated simultaneously with the two-dimensional grating 204, e.g., may be fabricated as a single piece.

It can be understood that, in the embodiment of the application, the method for adjusting and controlling the transparency of each light-passing hole 2040 in the two-dimensional grating 204 is not limited to the above-mentioned method, and may also include any other implementable method, and the purpose is to make the transparency of each light-passing hole 2040 in the two-dimensional grating 204 gradually increase along the direction from the central point of the light-emitting surface of the Mini LED chip 202 to the edge of the light-emitting surface of the Mini LED chip 202, so that the luminous flux of each light-passing hole 2040 gradually decreases along the direction from the central point of the light-emitting surface of the Mini LED chip 202 to the edge of the light-emitting surface of the Mini LED chip 202, thereby achieving more uniform light passing through the two-dimensional grating 204.

In a third practical solution, the density of the light passing holes 2040 of the two-dimensional grating 204 may be gradually increased along a direction from the center point of the light emitting surface of the Mini LED chip 202 to the edge of the light emitting surface of the Mini LED chip 202. For example, the spacing distance between adjacent light-passing holes 2040 of the two-dimensional grating 204 may be gradually decreased along the direction from the central point of the light-emitting surface of the Mini LED chip 202 to the edge of the light-emitting surface of the Mini LED chip 202, so that the light-passing holes 2040 in the edge area of the two-dimensional grating 204 are more dense relative to the light-passing holes in the central area, the light flux in the central area of the two-dimensional grating 204 can be reduced, the light flux in the edge area of the two-dimensional grating 204 can be increased, and the light passing through the two-dimensional grating 204 is more uniform.

It is understood that any combination of the above embodiments can be used to achieve the suppression of the central light intensity of the Mini LED chip 202 and improve the light-homogenizing effect. Some of these combinations are briefly described below:

for example, in a case that the size of the light passing hole 2040 of the two-dimensional grating 204 gradually increases along a direction in which the center point of the light emitting surface of the Mini LED chip 202 points to the edge of the light emitting surface of the Mini LED chip 202, or the sizes of the light passing holes 2040 of the two-dimensional grating 204 are the same, the light passing hole 2040 may be filled with metal layers with different thicknesses, so that the transparency of the metal layer of the light passing hole 2040 of the two-dimensional grating 204 gradually increases along a direction in which the center point of the light emitting surface of the Mini LED chip 202 points to the edge of the light emitting surface of the Mini LED chip 202.

Or, the size of the light passing holes 2040 of the two-dimensional grating 204 may gradually increase along the direction from the central point of the light emitting surface of the Mini LED chip 202 to the edge of the light emitting surface of the Mini LED chip 202, or the spacing distance between adjacent light passing holes 2040 of the two-dimensional grating 204 may gradually decrease along the direction from the central point of the light emitting surface of the Mini LED chip 202 to the edge of the light emitting surface of the Mini LED chip 202 under the condition that the sizes of the light passing holes 2040 of the two-dimensional grating 204 are the same.

Alternatively, the light-passing holes 2040 may be filled with metal layers of different thicknesses, so that the transparency of the metal layer of the light-passing hole 2040 in the two-dimensional grating 204 gradually increases along the direction from the central point of the light-emitting surface of the Mini LED chip 202 to the edge of the light-emitting surface of the Mini LED chip 202, and the spacing distance between adjacent light-passing holes 2040 in the two-dimensional grating 204 gradually decreases along the direction from the central point of the light-emitting surface of the Mini LED chip 202 to the edge of the light-emitting surface of the Mini LED chip 202. Or, while the size of the light passing holes 2040 of the two-dimensional grating 204 gradually increases along the direction in which the central point of the light emitting surface of the Mini LED chip 202 points to the edge of the light emitting surface of the Mini LED chip 202, the light passing holes 2040 are filled with metal layers of different thicknesses so that the transparency of the metal layer of each light passing hole 2040 of the two-dimensional grating 204 gradually increases along the direction in which the central point of the light emitting surface of the Mini LED chip 202 points to the edge of the light emitting surface of the Mini LED chip 202, and the spacing distance between adjacent light passing holes 2040 of the two-dimensional grating 204 gradually decreases along the direction in which the central point of the light emitting surface of the Mini LED chip 202 points to the edge of the light emitting surface of the Mini LED chip 202.

In the embodiment of the present application, the manufacturing process of the two-dimensional grating 204 above each Mini LED chip 202 includes, but is not limited to, yellow light etching or nano-imprinting, wherein the material of the two-dimensional grating 204 may be a strong reflective metal material, and the thickness of the two-dimensional grating 204 may be in a range of 0.5 to 10 micrometers.

In the embodiment of the present application, after the two-dimensional grating 204 is manufactured, as shown in fig. 8, a whole surface of the two-dimensional grating 204 is subjected to a sealing process to form a packaging adhesive layer 203, wherein the packaging adhesive layer 203 covers the entire Mini LED chip array and the two-dimensional grating 204 on the entire Mini LED chip array.

In some embodiments, in order to further improve the light uniformizing effect, as shown in fig. 9, the backlight structure provided in the embodiments of the present application may include forming a micro-structural layer on the encapsulation adhesive layer 203, wherein the micro-structural layer may include a rugged shape formed on the encapsulation adhesive layer 203, so that an upper surface of the encapsulation adhesive is a rough surface. Specifically, a plurality of raised structures 2030 may be prepared on the encapsulation adhesive layer 203 to form a micro-structural layer, wherein the shapes of the raised structures 2030 may be a cone, a cylinder, a hemispherical protrusion, an irregular protrusion, and the like.

The micro-structure layer can realize diffuse reflection of an interference dot matrix generated by diffraction light of the two-dimensional grating 204 into a uniform surface light source. Therefore, the uniformity of the brightness of each pixel point in the light-emitting display layer above the backlight source structure is effectively improved.

In the embodiment of the present application, the material of the microstructure layer may be the same as the material of the encapsulation adhesive layer, and the fabrication method may be implemented by yellow etching or nano-imprinting encapsulation adhesive, or by other methods.

In addition, in order to avoid the light mixing effect caused by the exiting light at the side of the Mini LED chips 202, that is, the occurrence of the mutual crosstalk between the lights of the two adjacent Mini LED chips, for example, when one of the two adjacent Mini LED chips 202 is turned on and the other is not turned on, the side light of the turned-on Mini LED chip 202 is interfered above the unlit Mini LED chip 202, and the light intensity appears in the screen area corresponding to the unlit Mini LED chip 202.

As shown in fig. 10, in the backlight structure provided in the embodiment of the present application, a reflective layer 208 may be further disposed above a gap between any two adjacent Mini LED chips in the Mini LED chip array. For example, the reflective layer 208 may be disposed over the gap of the first Mini LED chip 2021 and its adjacent second Mini LED chip 2022 shown in fig. 10. At least a partial region of the reflective layer 208 is disposed on the surface of the light-emitting surface of the first Mini LED chip 2021, and at least a partial region is disposed on the surface of the light-emitting surface of the second Mini LED chip 2022. The reflective layer 208 may be made of a material with a strong light-reflecting effect. Wherein the reflective layer 208 covers the entire gap between the first Mini LED chip 2021 and the second Mini LED chip 2022. The reflective layer 208 can totally reflect the emergent light from the side of any one Mini LED chip of the first Mini LED chip 2021 and the second Mini LED chip 2022 to the other Mini LED chip, thereby effectively reducing the light mixing effect between the chips.

For example, as shown in fig. 11a, the reflective layer 208 may totally reflect the light emitted from the side of the first Mini LED chip 2021 to the adjacent second Mini LED chip 2022, thereby reducing the light mixing effect between the adjacent Mini LED chips.

In some embodiments, the reflective layer 208 may be fabricated after the two-dimensional grating 204 is fabricated.

In some embodiments, the reflective layer 208 and the two-dimensional grating 204 may be disposed in the same layer in the light-emitting direction of the Mini LED chip 202. In some embodiments, the reflective layer 208 and the two-dimensional grating 204 may be the same thickness. The light emitting direction of the Mini LED chip 202 may be along the thickness direction of the two-dimensional grating 204.

In some embodiments, as shown in FIG. 11b, the reflective layer 208 and the two-dimensional grating 204 may be made of the same material, for example, both may be made of a strong reflective metal material such as gold, silver or aluminum

In some embodiments, the reflective layer 208 and the plurality of two-dimensional gratings 204 may be formed by integral molding. For example, in the preparation process, a metal layer made of a strong reflective material may be prepared on the upper surface of the light-emitting surface of the Mini LED chip 202 through a yellow etching process or a nanoimprint process, then a set number of light-passing holes are formed on the metal layer corresponding to a single Mini LED chip 202 to form the two-dimensional grating 204, and the metal layer above the space between every two adjacent Mini LED chips (e.g., as shown in fig. 11b, the first Mini LED chip 2021 and the second Mini LED chip 2022 of the adjacent chip) is retained to form the reflective layer 208. One end of the formed reflective layer 208 is disposed above the light-emitting surface of the first Mini LED chip 2021, and the other end of the reflective layer 208 is disposed above the light-emitting surface of the second Mini LED chip 2022.

It can be understood that, as shown in fig. 11c, when the fillers in the reflective layer 208, the two-dimensional grating 204 and the light passing hole 2040 are all made of the same material, the fillers in the reflective layer 208, the two-dimensional grating 204 and the light passing hole 2040 can all be integrally formed.

For example, in the preparation process, a metal layer made of a strong reflective material may be prepared above the light emitting surface of the Mini LED chip 202 through a yellow etching process or a nanoimprint process, and then a plurality of grooves with a set depth and a set interval are formed on the metal layer at positions corresponding to the single Mini LED chip 202 to form the two-dimensional grating 204, and the metal layer above the interval between every two adjacent Mini LED chips (for example, as shown in fig. 11c, the first Mini LED chip 2021 and the second Mini LED chip 2022 of the adjacent chip thereof) is retained to form the reflective layer 208. One end of the formed reflective layer 208 is disposed above the light-emitting surface of the first Mini LED chip 2021, and the other end of the reflective layer 208 is disposed above the light-emitting surface of the second Mini LED chip 2022.

In the embodiment of the present application, as shown in fig. 12, the backlight structure may further include a diffusion layer 209, where the diffusion layer 209 may be disposed above the microstructure layer, so that light passing through the microstructure layer may be further diffused through the diffusion layer. In the backlight source structure provided in the embodiment of the present application, the number of the diffusion layers 209 may be one or multiple. The embodiments of the present application are not limited herein. In some embodiments, in embodiments where no micro-structured layer is provided, the diffusion layer 209 may also be provided on the upper surface of the encapsulating glue layer 203.

To sum up, the backlight structure that this application embodiment provided is through setting up the two-dimensional grating that has a plurality of logical unthreaded holes above the Mini LED chip, can make the light that the Mini LED chip sent take place the diffraction through the logical unthreaded hole of two-dimensional grating and produce diffraction light, and diffraction light can take place alternately to produce at the in-process of spreading and interfere the even light dot matrix of formation, can effectively promote the homogeneity of each pixel luminance in the luminescent display layer above the Mini LED chip. Furthermore, the upper portion of the backlight source structure packaging adhesive layer provided by the embodiment of the application forms a micro-structure layer, and interference dot matrixes generated by diffraction light rays passing through the two-dimensional grating can be subjected to diffuse reflection to form an even surface light source. Therefore, the brightness uniformity of each pixel point in the light-emitting display layer above the backlight source structure is further improved.

On the other hand, the embodiment of the application provides a display module, which comprises a light-emitting display layer and the backlight source structure. The light emitting display layer can be arranged above the backlight source structure.

On the other hand, the embodiment of the application further provides electronic equipment, and the electronic equipment can comprise the display module. The electronic device includes, but is not limited to, an electronic device such as a mobile phone, a tablet, a computer, a display, a large screen terminal, and the like.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present application without departing from the scope of the application. It is intended that the present application also cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

Claims

1. A backlight structure, comprising: the light emitting device comprises a substrate, a plurality of light emitting units and a plurality of two-dimensional gratings;

the two-dimensional grating comprises a plurality of light through holes which are communicated with the first surface and the second surface of the two-dimensional grating; the first surface is a surface opposite to a light-emitting surface of the light-emitting unit, and the second surface is opposite to the first surface.

2. The backlight structure of claim 1, wherein the light emitting units are Mini LED chips.

3. The backlight structure of claim 1, wherein the plurality of light passing holes on the two-dimensional grating are the same in shape and size.

4. The backlight structure as claimed in claim 1, wherein the size of the plurality of light holes on the two-dimensional grating gradually increases along a direction from a center point of the light emitting surface of the light emitting unit to an edge of the light emitting surface of the light emitting unit.

5. The backlight structure according to any one of claims 1 to 4, wherein a filler is disposed in the plurality of light-passing holes on the two-dimensional grating, and a transparency of the filler in the plurality of light-passing holes gradually increases along a direction from a center point of the light-emitting surface of the light-emitting unit to an edge of the light-emitting surface of the light-emitting unit.

6. The backlight structure as claimed in claim 5, wherein the thickness of the filler gradually decreases along a direction from the center of the light-emitting surface of the light-emitting unit to the edge of the light-emitting surface of the light-emitting unit.

7. The backlight structure of claim 6, wherein the filler is made of the same material as the two-dimensional grating.

8. The backlight structure of claim 7, wherein the filler and the two-dimensional grating are integrally formed as a unitary structure.

9. The backlight structure according to any one of claims 1 to 4 and 6 to 8, wherein the distribution density of the plurality of light passing holes on the two-dimensional grating gradually increases along a direction from the center point of the light emitting surface of the light emitting unit to the edge of the light emitting surface of the light emitting unit.

10. The backlight structure as claimed in claim 5, wherein the distribution density of the plurality of light passing holes on the two-dimensional grating gradually increases along a direction from the center point of the light emitting surface of the light emitting unit to the edge of the light emitting surface of the light emitting unit.

11. The backlight structure of claim 1, further comprising an encapsulation adhesive layer disposed above the two-dimensional gratings and covering the light emitting units and the two-dimensional gratings.

12. The backlight structure of claim 11, further comprising a micro-structured layer disposed on the light-emitting surface of the encapsulant layer;

13. The backlight structure according to claim 1, comprising a reflective layer disposed over a gap between adjacent ones of the plurality of light-emitting units;

at least a first partial area of the reflecting layer is arranged on the light-emitting surface of one of the adjacent light-emitting units, and at least a second partial area of the reflecting layer is arranged on the light-emitting surface of the other of the adjacent light-emitting units.

14. The backlight structure of claim 13, wherein the reflection layer and the two-dimensional grating are disposed in the same layer in a light emitting direction of the light emitting unit.

15. The backlight structure of claim 13 or 14, wherein the reflective layer is made of the same material as the two-dimensional grating, and the reflective layer and the two-dimensional grating are integrally formed.

16. The backlight structure of claim 12, further comprising a diffusion layer disposed on a side of the micro-structural layer opposite to the encapsulant layer.

17. A display module comprising a light-emitting display layer and the backlight structure of any one of claims 1-16.

18. An electronic device comprising the display module of claim 17.