CN113985656A

CN113985656A - Backlight source, backlight module and display device

Info

Publication number: CN113985656A
Application number: CN202111257905.3A
Authority: CN
Inventors: 赵雪梅; 李虎; 谢登玲; 雷阳阳; 张勇; 汪张宝
Original assignee: BOE Technology Group Co Ltd; Hefei BOE Optoelectronics Technology Co Ltd
Current assignee: BOE Technology Group Co Ltd; Hefei BOE Optoelectronics Technology Co Ltd
Priority date: 2021-10-27
Filing date: 2021-10-27
Publication date: 2022-01-28
Anticipated expiration: 2041-10-27
Also published as: CN113985656B

Abstract

The application provides a backlight source, a backlight module and a display device; the backlight includes: the light emitting device comprises a substrate, a light emitting unit group and a light emitting unit group, wherein the substrate is provided with a plurality of light emitting unit groups, and each light emitting unit group comprises at least one light emitting unit; a first diffusion film corresponding to an area within a light emitting angle of the light emitting unit is arranged on a light emitting side of the light emitting unit, and the reflectivity of the first diffusion film is greater than the transmissivity; for at least part of the light-emitting units, a first reflection structure surrounding the light-emitting units is further arranged on the substrate, and the first reflection structure is used for reflecting the light reflected by the first diffusion film towards the direction of the area outside the light-emitting angle of the light-emitting units. The scheme of this application can effectually eliminate the luminance difference of luminescence unit rather than peripheral region, prevents the bad effect of lamp shadow, and then promotes the display effect.

Description

Backlight source, backlight module and display device

Technical Field

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

Background

Backlight sources of liquid crystal display are classified into a side-in type and a direct type, wherein the LEDs in the direct type backlight source directly form a surface light source in an array manner. The existing direct type backlight source mainly adopts Mini LEDs, has the advantage of realizing High-Dynamic Range (HDR) display based on the characteristics of miniaturization, High brightness, High color gamut, zone-controllable performance and the like, and is widely applied to various display devices.

In the related art, the backlight is divided into a plurality of lamp regions, and each lamp region can be individually controlled. However, in the working process of the backlight source in the related art, the problem that the abutted seams between the lamp shadow and the lamp section are obvious generally exists, and the display effect is seriously influenced.

Disclosure of Invention

In view of the above, an object of the present application is to provide a backlight source, a backlight module and a display device.

In view of the above, the present application provides a backlight including: the light emitting device comprises a substrate, a light emitting unit group and a light emitting unit group, wherein the substrate is provided with a plurality of light emitting unit groups, and each light emitting unit group comprises at least one light emitting unit; a first diffusion film corresponding to an area within a light emitting angle of the light emitting unit is arranged on a light emitting side of the light emitting unit, and the reflectivity of the first diffusion film is greater than the transmissivity; for at least part of the light-emitting units, a first reflection structure surrounding the light-emitting units is further arranged on the substrate, and the first reflection structure is used for reflecting the light reflected by the first diffusion film towards the direction of the area outside the light-emitting angle of the light-emitting units.

Based on the same inventive concept, the present application further provides a backlight module, including: a backlight as claimed in any preceding claim.

Based on the same inventive concept, the present application further provides a display device comprising: a liquid crystal display panel and the backlight module as described above.

As can be seen from the above, in the backlight, the backlight module, and the display device provided by the present application, the first diffusion film is provided on the light exit side of the light emitting unit, the first diffusion film corresponds to the region within the light emission angle of the light emitting unit, and the reflectance of the first diffusion film is set to be greater than the transmittance, so that a substantial part of the light transmitted to the first diffusion film is reflected in the direction in the vicinity of the light emitting unit; correspondingly, still be provided with first reflection configuration around the luminescence unit, this first reflection configuration can reflect the light that first diffusion barrier reflection comes towards the direction in the region beyond the luminescence angle of luminescence unit, thereby make the region beyond the luminescence angle of luminescence unit have more light outgoing, make the whole mixed light more even on the luminescence unit light-emitting direction, the effectual luminance difference of eliminating luminescence unit and its peripheral region, prevent the bad effect of lamp shadow, and then promote display effect.

Drawings

In order to more clearly illustrate the technical solutions in the present application or the related art, the drawings needed to be used in the description of the embodiments or the related art will be briefly introduced below, and it is obvious that the drawings in the following description are only embodiments of the present application, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic diagram illustrating a lamp shadow phenomenon of a backlight according to the related art;

fig. 2 is a schematic top-view structural diagram of a backlight according to an embodiment of the present disclosure;

fig. 3 is a schematic structural diagram of a single light-emitting unit in a backlight according to an embodiment of the present disclosure;

FIG. 4 is a schematic top view of two adjacent lamp regions in a backlight according to an embodiment of the present disclosure;

FIG. 5 is a schematic diagram of a single light-emitting unit according to another alternative embodiment of the present application;

FIG. 6(a) is a schematic diagram of ideal brightness of each lamp region in the backlight;

fig. 6(b) is a luminance diagram of actual states of the lamp regions in the backlight.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is further described in detail below with reference to the accompanying drawings in combination with specific embodiments.

It should be noted that technical terms or scientific terms used in the embodiments of the present application should have a general meaning as understood by those having ordinary skill in the art to which the present application belongs, unless otherwise defined. The use of "first," "second," and similar terms in the embodiments of the present application do not denote any order, quantity, or importance, but rather the terms are used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly.

As described in the background section, in the backlight source in the related art, there is a problem that the seams between the lamp shadow and the lamp area are obvious in the working process. Referring to fig. 1, that is, a phenomenon that a lamp shadow is obvious when the backlight in the related art works, when observed from the outside of the backlight, a difference between a brightness of a Mini LED and a brightness of a peripheral area of the Mini LED can be obviously observed, which may seriously affect a display effect. In the process of implementing the solution of the present application, the applicant finds that the reason for the obvious problem of the lamp shadow and the abutted seam between the lamp zones in the backlight in the related art is that: for a single Mini LED, the light emission intensity in the light emission angle region (generally, a conical region about 120 ° directly above the Mini LED) is significantly higher than the light emission intensity in the region other than the light emission angle, and even if other existing light mixing members (such as a diffusion film, a quantum dot film, and the like) arranged on the backlight cannot effectively compensate the difference of the light emission intensities, the light shadow can be obviously observed from the outside of the backlight. For different lamp zones, because the Mini LEDs in the lamp zones have the problem of the above-mentioned difference in luminous intensity, the luminous intensity between different lamp zones is also made to be uneven correspondingly, that is, the problem of obvious abutted seams between lamp zones is caused.

In view of the above problems in the related art, the present application provides a backlight source, and a backlight module and a display device using the backlight source. In the backlight provided by the application, the first diffusion film is arranged on the light-emitting side of the light-emitting unit, corresponds to the area within the light-emitting angle of the light-emitting unit, and the reflectivity of the first diffusion film is set to be greater than the transmissivity, so that a part of light transmitted to the first diffusion film is reflected towards the direction close to the light-emitting unit; correspondingly, still be provided with first reflection configuration around the luminescence unit, this first reflection configuration can reflect the light that first diffusion barrier reflection comes towards the direction in the region beyond the luminescence angle of luminescence unit, thereby make the region beyond the luminescence angle of luminescence unit have more light outgoing, make the whole mixed light more even on the luminescence unit light-emitting direction, the effectual luminance difference of eliminating luminescence unit and its peripheral region, prevent the bad effect of lamp shadow, and then promote display effect. In addition, in some embodiments, the second reflection structure is disposed at an edge of the lamp region for a problem of halo existing in the backlight source, and the second reflection structure reflects light reflected by the first diffusion film in a direction perpendicular to the substrate, so that light emitted from one lamp region does not overflow to an adjacent lamp region, thereby solving the problem of halo.

Hereinafter, the embodiments of the present application will be described in further detail with reference to specific examples.

First, an embodiment of the present application provides a backlight. Referring to fig. 1 and 2, the backlight includes: a substrate 10. The substrate 10 serves as a base structure for the backlight for carrying other components. In order to realize the partition control of the backlight, a driving circuit for realizing the partition control of the backlight is further disposed on the substrate 10. Specifically, the substrate 10 may be a Flexible Printed Circuit (FPC), and based on the light and thin characteristics of the FPC, the substrate may be correspondingly used in portable electronic products such as a tablet computer; the substrate 10 may also be a glass pcb (printed Circuit board) for electronic products with general dimensions. The specific material and specification of the substrate 10 and the specific implementation manner of the driving circuit thereon may be selected from any related technologies, and are not limited in this embodiment.

Referring to fig. 2, a substrate 10 is provided with a plurality of light emitting cell groups, each of which includes at least one light emitting cell 20. Corresponding to the backlight partition control, the area defined by one light emitting unit group is the lamp area 101 (the area defined by the dashed line frame in fig. 1). That is, the substrate 10 is divided into a plurality of lamp regions 101, and a light emitting unit group composed of at least one light emitting unit 20 is disposed in each lamp region 101. The light emitting unit 20 may be a Mini LED; the light emitting unit 20 may also be other light emitting components, such as Micro-LEDs, OLEDs, etc., according to specific implementation requirements. In addition, it should be noted that, for the sake of more clear expression of the structure, only the light emitting units 20 and the lamp regions 101 are shown in fig. 2, and each lamp region 101 includes four light emitting units 20 as an example; the number of light emitting units 20 included in the lamp region 101 may be different from that illustrated in the embodiments of the present application according to specific implementation requirements.

Referring to fig. 3, a cross-sectional view of a single light emitting unit 20 in a direction perpendicular to the substrate 10 is shown, the light emitting unit 20 is shown near the edge of the lamp region 101, and only the structure of the light emitting unit 20 near the edge of the lamp region 101 is shown for a simplified representation. The light emitting side of the light emitting unit 20 is provided with a first diffusion film 30 corresponding to a region within the light emitting angle of the light emitting unit 20. The light emitting angle of the light emitting unit 20 refers to the central angle of the conical area corresponding to the light emitted by the light emitting unit, and the area within the light emitting angle is the area shown by the two dotted lines in the light emitting direction of the light emitting unit 20 in fig. 3, and generally the light emitting angle is 120 ° to 150 °. The light emitting unit 20 has a stronger light emitting intensity in the area within the light emitting angle, so as to cause the problem of the uneven light mixing in the related art.

In this embodiment, the first diffusion film 30 is provided corresponding to a region within the light emission angle of the light emitting unit 20. The first diffusion film 30 may be formed on the light emitting cell 20 through a communication process, and it is understood that the first diffusion film 30 may be a part of a communication process forming an entire diffusion film layer having a light uniformizing function similar to that of the related art. In addition, the formed diffusion film layer may further include a second diffusion film 40 corresponding to a region outside the light emission angle of the light emitting unit 20.

Specifically, in addition to the basic dodging function, the optical properties of the first diffusion film 30 are further improved to be set to be greater in reflectance than in transmittance. Based on the optical property that the reflectance is greater than the transmittance, a smaller part of the light emitted from the light emitting unit 20 passes through the first diffusion film 30 after reaching the first diffusion film 30, and a larger part of the light is reflected by the first diffusion film 30 and then emitted to the light emitting unit 20 and a region outside the light emitting angle of the light emitting unit 20; the optical path of the light reflected by the first diffusion film 30 can be schematically shown with reference to a dotted line with an arrow in fig. 3.

As an alternative embodiment, referring to fig. 3, the arrangement in which the reflectance of the first diffusion film 30 is greater than the transmittance may be achieved by arranging the first particle structure on the first diffusion film 30. Specifically, a certain number of first particle structures 301 are disposed on a surface of the first diffusion film 30 on a side away from the light emitting unit 20, and by setting the size and distribution density of the first particle structures 301, the first diffusion film 30 can have a high haze, so that the reflectance of the first diffusion film 30 is greater than the transmittance. For example, if the distribution density is constant, the size of the first particle structure 301 can be set to be larger, and thus higher haze can be achieved; as another example, in the case where the size of the first particle structure 301 is constant, the distribution density of the first particle structure 301 is set to be large, that is, dense, thereby achieving higher haze. The first particle structure 301 may be formed on the surface of the first particle structure 301 by a coating process.

Further, referring to fig. 3, in addition to the first particle structure 301, a number of second particle structures 302 may be further provided on a surface of the first diffusion film 30 on a side close to the light emitting unit 20. By the arrangement of the second particle structures 302, the probability that light is reflected when reaching the surface of the first particle structure 301 on the side close to the light emitting unit 20 can be increased, thereby further increasing the reflectivity of the first diffusion film 30, and reflecting more light to the region outside the light emitting angle of the light emitting unit 20.

In the present embodiment, referring to fig. 3 and 4, as a structure cooperating with the first diffusion film 30, a first reflection structure 50 surrounding the light emitting unit 20 is further provided on the substrate 10. Fig. 4 is a top view of two adjacent lamp regions in a direction perpendicular to the substrate 10, and it can be seen that the first reflective structure 50 is disposed around the light emitting unit 20. The first reflective structure 50 is located around the periphery of the light emitting unit 20, and corresponds to a region outside the light emitting angle of the light emitting unit 20. For the light reflected by the first diffusion film 30, the first reflection structure 50 can reflect the light toward the region outside the light emitting angle of the light emitting unit 20, and the specific light path can be shown by the dotted line with an arrow in fig. 3. The light reflected by the first diffusion film 30 is reflected by the first reflection structure 50, propagates in a direction of a region other than the light emission angle of the light emitting unit 20, and is emitted after passing through the second diffusion film 40 corresponding to the region other than the light emission angle of the light emitting unit 20. As can be seen, based on the high reflectivity of the first diffusion film 30, a larger part of the light emitted by the light emitting unit 20 will be reflected by the first diffusion film 30 to the first reflection structure 50, and then emitted from the region outside the light emitting angle of the light emitting unit 20 after being reflected by the first reflection structure 50; that is, through the arrangement of the first diffusion film 30 and the first reflection structure 50, the portion in the light emitting unit 20 is changed to be emitted from the region outside the light emitting angle of the light emitting unit 20, so that the overall light mixing in the light emitting direction of the light emitting unit 20 is more uniform, the brightness difference caused by the concentration of the light emitted from the light emitting unit 20 is effectively eliminated, and the problem of lamp shadow is avoided.

The material of the first reflective structure 50 may be white glue or white ink with a high reflectivity. For the fabrication process, the first reflective structure 50 may be formed on the substrate 10 through a spray coating or patterning process. In addition, to achieve a better light-uniformizing effect, the first reflective structures 50 may be correspondingly disposed on all the light-emitting units 20; the first reflective structure 50 may be disposed only on a portion of the light emitting unit 20 according to specific implementation requirements.

As an alternative embodiment, referring to fig. 3, the first reflection structure 50 may include a first reflection plane 501, the first reflection plane 501 and the substrate 10 form an angle, and based on the angle, the light reflected by the first diffusion film 30 can be reflected at the first reflection plane 501 to an area outside the light emitting angle of the light emitting unit 20. The angle formed by the first reflecting plane 501 and the substrate 10 can be obtained through experimental tests according to the rule and corresponding setting of the whole backlight source and other components, and the embodiment is not particularly limited as long as the reflecting is performed in the region other than the light emitting angle of the light emitting unit 20. In addition, the overall structure of the first reflective structure 50 may be a triangle as shown in fig. 3, or may also be a trapezoid, or the like, or an irregular shape, which only needs to have a plane forming a certain angle with the substrate 10 as the first reflective plane 501. In addition, the number of the first reflective structures 50 may also be set according to implementation requirements, for example, the first reflective structures may be multiple and sequentially arranged around as shown in fig. 3.

As an alternative embodiment, referring to fig. 5, the first reflective structure 50 may include a reflective arc surface 501 ', the reflective arc surface 501' being arched away from the substrate 10. Based on the arched structure, the reflective arc surface 501' can reflect the light reflected by the first diffusion film 30 in a direction toward a region other than the light emission angle of the light emitting unit 20. Due to the arc structure characteristics of the reflective arc 501', light can form diffuse reflection during reflection, so that light uniformization can be realized at the first reflective structure 50, and the overall light uniformization effect of the light emitting unit 20 can be improved to a certain extent.

As an alternative embodiment, referring to fig. 3, for the second diffusion film 40 corresponding to the region outside the light emitting angle of the light emitting unit 20, the optical property of the second diffusion film 40 may be set to be greater in transmittance than in reflectance. Through setting up second diffusion barrier 40 and having higher transmissivity, the corresponding region that makes light-emitting unit 20 outside the luminous angle has more emergent light, can further increase the luminance of region outside the luminous angle of light-emitting unit 20 like this, and the luminance difference inside and outside the luminous angle of more effectual reduction light-emitting unit 20 to the harmful effects of lamp shadow are prevented appearing, promote display effect.

Specifically, the arrangement in which the transmittance of the second diffusion film 40 is larger than the reflectance can be realized by providing the second particle structure 401 on the second diffusion film 40. The surface of the second diffusion film 40 on the side far away from the light emitting unit 20 is provided with a certain number of second particle structures 401, and by setting the size and distribution density of the second particle structures 401, the second diffusion film 40 can have a low haze, so that the transmittance of the second diffusion film 40 is greater than the reflectance. The specific arrangement may refer to the aforementioned example of arranging the first particle structure 301, and the opposite arrangement may be sufficient. In addition, the arrangement of the second particle structure 401 can also enable light to be scattered when the light exits through the second diffusion film 40, so that the overall light uniformizing effect is further improved.

As an optional embodiment, the backlight of this embodiment further includes a second reflective structure for solving the halo problem.

In the related art, when a bright object is displayed, light emitted from a lamp region where a backlight mainly emits light leaks to a lamp region adjacent to a dark color, and a halo phenomenon is easily observed from an external view. The main reason for this is that light emitted from the lamp region leaks to the adjacent lamp region. Referring to fig. 6(a) and 6(b), light emission luminance diagrams of the ideal state and the actual state of each lamp zone are shown, respectively. In fig. 6(a) and 6(b), the horizontal axis represents each lamp region, each broken line frame corresponds to one lamp region, and the vertical axis represents brightness. Wherein, fig. 6(a) is an ideal state, the central light-emitting lamp area emits light uniformly and does not overflow to the adjacent lamp areas; fig. 6(b) shows an actual state, that is, a state where halo occurs, the central light-emitting lamp region is affected by light of the adjacent lamp regions, and light of the central light-emitting lamp region overflows to the adjacent sub-regions.

In view of the above-mentioned halo problem, the present embodiment further includes a second reflective structure for solving the halo problem. Referring to fig. 3 and 4, for one lamp region, a second reflective structure 60 is further disposed on the substrate 10 near and around the edge of the lamp region. The second reflecting structure 60 is located at the edge of the lamp area and is arranged to surround the lamp area and may act on all edge positions of the lamp area. For the light reflected by the first diffusion film 30, the second reflection structure 60 can reflect the light toward the direction perpendicular to the substrate 10, and the specific light path can be schematically shown by the dotted line with an arrow in fig. 3 through the second reflection structure 60. It can be seen that the second reflective structure 60 can reflect the light transmitted to the edge of the lamp area, and the reflected direction is perpendicular to the substrate 10, so that the light transmitted to the edge of the lamp area is limited to exit towards the adjacent lamp area, but all exit towards the light exit direction of the lamp area, thereby solving the problem of light leakage to the adjacent lamp area and eliminating the bad phenomenon of halo. Through experiments, the backlight source of the embodiment of the present application can achieve the effect shown in fig. 6(a) when actually emitting light through the arrangement of the second reflective structure 60.

The second reflective structure 60 may be made of a material and manufactured by a process similar to those of the first reflective structure 50. In addition, in order to achieve a better halo elimination effect, the second reflection structures 60 can be correspondingly arranged in all the lamp regions; the second reflective structure 60 may also be provided for only a portion of the lamp area, depending on the particular implementation.

As an alternative embodiment, referring to fig. 3 or fig. 4, the second reflective structure 60 may include a second reflective plane 601, where the second reflective plane 601 is at an angle with respect to the substrate 10, and based on the angle, the light reflected by the first diffusion film 30 can be reflected at the second reflective plane 601 in a direction perpendicular to the substrate 10. The angle formed by the second reflective structure 60 and the substrate 10 may be obtained through experimental tests according to the rule and the corresponding setting of the whole backlight source and other components, and the embodiment is not particularly limited as long as the light is reflected toward the direction perpendicular to the substrate 10. In addition, the overall structure of the second reflective structure 60 may be a triangular body as shown in fig. 3, or may also be a trapezoidal body, or an irregular shape, which only needs to have a plane forming a certain angle with the substrate 10 as the second reflective structure 60.

Further, to ensure that light in a lamp region does not substantially leak out to an adjacent lamp region at all, the height of the second reflecting structure 60, which is the length in the direction perpendicular to the substrate 10, has a corresponding setting. Referring to fig. 3 or 4, an encapsulation layer 70 for encapsulating the light emitting unit 20 is also provided on the substrate 10. In addition to the light emitting unit 20, the first reflective structure 50 and the second reflective structure 60 are also encapsulated in the encapsulation layer 70. In order to achieve the light-tight effect, the height of the second reflective structure 60 may be set to be close to or substantially the same as the height of the encapsulation layer 70, and specifically, the height of the second reflective structure 60 may be set to be 0.8-1 times the height of the encapsulation layer 70. For example, for a common backlight, the height of the light emitting unit 20 is about 0.15mm, and the height of the encapsulation layer 70 is about 0.3mm, the height of the second reflective structure 60 may be set in a range of [0.25mm-0.3mm ].

In specific implementation, the height of the second reflective structure 60 can be set according to specific structural parameters of the backlight source. Specifically, the height of the second reflection structure 60 is in a direct relationship with the distance from the light emitting unit 20 to the first diffusion film 30, and in an inverse relationship with the distance from the edge of the lamp region to the light emitting unit 20. It is to be understood that since the second reflection structure 60 is disposed near the edge of the lamp region, the above-mentioned interval refers to an interval between the edge of the lamp region and the adjacent light emitting unit 20. Based on the above correspondence, the height of the second reflecting structure 60 can be calculated by the following formula:

where a is the height of the second reflective structure 60, h is the distance from the light emitting unit 20 to the first diffusion film 30, and d is the distance from the edge of the lamp region to the light emitting unit 20.

In some embodiments, referring to fig. 3 and 4, for two adjacent lamp zones, the lengths of the first reflective structure 50 and the second reflective structure 60 between the two adjacent lamp zones should not be too large, otherwise the dodging effect is easily affected. Therefore, the length of the orthographic projection of all the first reflecting structures 50 and the second reflecting structures 60 in the area between the two adjacent lamp areas on the substrate 10 can be set to be 0.3-0.6 times of the side length of the lamp areas, so that the light uniformizing effect is prevented from being influenced by the overlarge length of the first reflecting structures 50 and the second reflecting structures 60. The shape of the lamp area is generally designed to be square, and when the shape of the lamp area is other shapes, the side lengths of the corresponding sides at the positions where the first reflection structure 50 and the second reflection structure 60 are located may be used as references.

In addition, when designing the lengths of the first and

second reflection structures

50 and 60 between two lamp zones, the number of light emitting units 20 included in one lamp zone may also be considered. Specifically, the lengths of the first and second

reflective structures

50 and 60 can be calculated by the following formula:

where D is the length of the first and

second reflection structures

50 and 60 between two lamp zones, L is the side length of the lamp zones, and N is the number of light emitting units 20 included in the lamp zones.

As can be seen from the above embodiments, the first diffusion film is provided on the light exit side of the light emitting unit, corresponds to the region within the light emission angle of the light emitting unit, and by providing the first diffusion film with a reflectance greater than a transmittance, a substantial portion of the light propagating to the first diffusion film is reflected in the direction in the vicinity of the light emitting unit; correspondingly, still be provided with first reflection configuration around the luminescence unit, this first reflection configuration can reflect the light that first diffusion barrier reflection comes towards the direction in the region beyond the luminescence angle of luminescence unit, thereby make the region beyond the luminescence angle of luminescence unit have more light outgoing, make the whole mixed light more even on the luminescence unit light-emitting direction, the effectual luminance difference of eliminating luminescence unit and its peripheral region, prevent the bad effect of lamp shadow, and then promote display effect. In addition, in some embodiments, the second reflection structure is disposed at an edge of the lamp region for a problem of halo existing in the backlight source, and the second reflection structure reflects light reflected by the first diffusion film in a direction perpendicular to the substrate, so that light emitted from one lamp region does not overflow to an adjacent lamp region, thereby solving the problem of halo.

Based on the same inventive concept, the embodiment of the present application further provides a backlight module, which includes the backlight source described in any of the foregoing embodiments.

The backlight module of this embodiment, owing to used aforementioned any embodiment the backlight to can make the whole mixed light more even in the luminescence unit light-emitting direction, effectual elimination luminescence difference rather than peripheral region of luminescence unit, prevent the bad effect of lamp shadow, and then promote display effect. In addition, in some embodiments, the light emitted in one lamp area can not overflow to the adjacent lamp area, thereby solving the halo problem.

Based on the same inventive concept, the embodiment of the application further provides a display device, which comprises a liquid crystal display panel and the backlight module of any one of the embodiments.

The display device in this embodiment may be: any product or component with a display function, such as a display panel, electronic paper, a mobile phone, a tablet computer, a television, a notebook computer, a digital photo frame, a navigator and the like.

In the display device of this embodiment, since the backlight module described in any of the foregoing embodiments is used, the beneficial effects of the backlight module in the foregoing embodiments can be correspondingly achieved, and details are not repeated here.

Those of ordinary skill in the art will understand that: the embodiments in the present specification are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.

Those of ordinary skill in the art will understand that: the discussion of any embodiment above is meant to be exemplary only, and is not intended to intimate that the scope of the disclosure, including the claims, is limited to these examples; within the context of the present application, features from the above embodiments or from different embodiments may also be combined, steps may be implemented in any order, and there are many other variations of the different aspects of the embodiments of the present application as described above, which are not provided in detail for the sake of brevity.

The present embodiments are intended to embrace all such alternatives, modifications and variances which fall within the broad scope of the appended claims. Therefore, any omissions, modifications, substitutions, improvements, and the like that may be made without departing from the spirit and principles of the embodiments of the present application are intended to be included within the scope of the present application.

Claims

1. A backlight, comprising: the light emitting device comprises a substrate, a light emitting unit group and a light emitting unit group, wherein the substrate is provided with a plurality of light emitting unit groups, and each light emitting unit group comprises at least one light emitting unit; a first diffusion film corresponding to an area within a light emitting angle of the light emitting unit is arranged on a light emitting side of the light emitting unit, and the reflectivity of the first diffusion film is greater than the transmissivity; for at least part of the light-emitting units, a first reflection structure surrounding the light-emitting units is further arranged on the substrate, and the first reflection structure is used for reflecting the light reflected by the first diffusion film towards the direction of the area outside the light-emitting angle of the light-emitting units.

2. The backlight of claim 1, wherein a surface of the first diffusion film on a side away from the light-emitting unit is provided with a number of first particle structures, and wherein the size and/or distribution density of the first particle structures is configured to achieve a reflectance greater than a transmittance of the first diffusion film.

3. The backlight according to claim 2, wherein a surface of the first diffusion film on a side close to the light emitting unit is provided with a number of second particle structures for increasing a reflectivity of the first diffusion film.

4. The backlight of claim 1, wherein the first reflective structure comprises a first reflective plane at an angle to the substrate, the first reflective plane being configured to reflect light reflected by the first diffuser film in a direction away from the light emission angle of the light emitting unit.

5. The backlight of claim 1, wherein the first reflective structure comprises a reflective curved surface that is curved in a direction away from the substrate, and the reflective curved surface is configured to reflect light reflected by the first diffusion film in a direction other than a light emission angle of the light emitting unit.

6. The backlight according to claim 1, wherein a second diffusion film corresponding to a region other than a light emission angle of the light emitting unit is further provided on a light exit side of the light emitting unit, and a transmittance of the second diffusion film is greater than a reflectance.

7. The backlight of claim 6, wherein a surface of the second diffuser film on a side away from the light-emitting units is provided with a number of second particle structures, and wherein the size and/or distribution density of the second particle structures is configured to achieve a transmittance greater than a reflectance of the second diffuser film.

8. The backlight according to any one of claims 1 to 7, wherein for at least part of the light emitting unit groups, the substrate is further provided with a second reflection structure disposed close to an edge of an area defined by the light emitting unit groups and surrounding along the edge of the area, and the second reflection structure is configured to reflect light reflected by the first diffusion film in a direction perpendicular to the substrate.

9. The backlight of claim 8, wherein the second reflective structure comprises a second reflective plane at an angle to the substrate, the second reflective plane configured to reflect light reflected from the first diffuser film in a direction perpendicular to the substrate.

10. The backlight according to claim 8, wherein an encapsulation layer for encapsulating the light emitting unit is further provided on the substrate; in the direction perpendicular to the substrate, the height of the second reflecting structure is 0.8-1 times the height of the packaging layer.

11. The backlight of claim 10, wherein the height of the second reflective structure is proportional to the distance from the light emitting unit to the first diffuser film and inversely proportional to the distance from the edge of the area to the adjacent light emitting unit in the direction perpendicular to the substrate.

12. The backlight of claim 8, wherein for any two adjacent light emitting unit groups, the length of the orthographic projection of all the first reflective structure and the second reflective structure on the substrate, which is arranged in the region between the two adjacent light emitting units, is 0.3-0.6 times the side length of the region defined by the light emitting unit group.

13. The backlight source of claim 1, wherein the light emitting angle is a central angle of the conical area corresponding to the light emitted by the light emitting unit, and the central angle ranges from 120 ° to 150 °.

14. A backlight module, comprising: a backlight as claimed in any one of claims 1 to 13.

15. A display device, comprising: a liquid crystal display panel, and a backlight module as claimed in claim 14.