Edge-type backlight module and display device

Abstract

The present application discloses an edge-entry backlight module and a display device, which relate to the field of display technology and can improve the yellowing problem of the existing edge-entry backlight module away from the light source area, so as to improve the chromaticity uniformity of the light output by the edge-entry backlight module. The edge-entry backlight module comprises: a light source; a light guide plate, the light guide plate comprises a near light source area and a far light source area, the near light source area is located between the light source and the far light source area; an optical film, the optical film is arranged opposite to the light guide plate, and the optical film corresponding to the far light source area is provided with reflective particles.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to an edge-type backlight module and a display device. Background Art

[0002] In the field of display technology, edge-type backlights are widely used in small and medium-sized displays. In the current consumer market, due to the advantages of PC (polycarbonate) light guide plates in reliability, most of the light guide plates in edge-type backlights are PC light guide plates.

[0003] However, the PC light guide plate easily causes the edge-entry backlight module to produce yellowing in the area far away from the light source, resulting in poor chromaticity uniformity of the light output from the edge-entry backlight module. Summary of the invention

[0004] The embodiments of the present application provide an edge-type backlight module and a display device, which can improve the yellowing problem of the existing edge-type backlight module in the area far away from the light source, so as to improve the chromaticity uniformity of the light emitted by the edge-type backlight module.

[0005] According to a first aspect of an embodiment of the present application, there is provided an edge-lit backlight module, comprising:

[0006] light source;

[0007] A light guide plate, the light guide plate comprising a low light source area and a high light source area, the low light source area being located between the light source and the high light source area;

[0008] An optical film is arranged opposite to the light guide plate, and reflective particles are arranged on the optical film corresponding to the high light source area.

[0009] In some embodiments, the reflectivity of the optical film corresponding to the low light source region to visible light is lower than the reflectivity of the optical film corresponding to the high light source region to visible light.

[0010] In some embodiments, the reflective particles are disposed on the surface of the optical film; and / or,

[0011] The reflective particles are arranged inside the optical film.

[0012] In some embodiments, in a direction from the low light source region to the high light source region, a density of the reflective particles disposed on the optical film corresponding to the high light source region gradually increases.

[0013] In some embodiments, the reflective particles have a diameter in the range of 10-20 μm.

[0014] In some embodiments, the ratio of the area of ​​the high light source region to the total area of ​​the light guide plate is in the range of 1 / 3-3 / 5.

[0015] In some embodiments, the edge-lit backlight module provided in the embodiment of the present application further includes a plastic frame, and the plastic frame is used to fix the light guide plate, the optical film and the light source;

[0016] The reflectivity of the rubber frame corresponding to the high light source area to blue light is greater than the reflectivity of the rubber frame corresponding to the low light source area to blue light.

[0017] In some embodiments, the plastic frame portion corresponding to the low light source area surrounds the low light source area, and the plastic frame portion corresponding to the high light source area surrounds the high light source area.

[0018] In some embodiments, the reflectivity of the plastic frame corresponding to the high light source area to blue light is greater than 4%.

[0019] In some embodiments, the surface of the plastic frame corresponding to the high light source area is coated with a blue coating; or,

[0020] The plastic frame corresponding to the high light source area is doped with blue particles; or,

[0021] The rubber frame corresponding to the high light source area is made of blue material.

[0022] In some embodiments, the optical film includes a first optical film and a second optical film, wherein the first optical film is disposed on a side of the light guide plate where a light emitting surface is located, and the second optical film is disposed on a side of the light guide plate away from the light emitting surface.

[0023] In some embodiments, the first optical film includes a first diffuser and / or a brightness enhancement film.

[0024] In some embodiments, the second optical film includes a second diffuser and / or a reflector.

[0025] In some embodiments, when the second optical film includes the reflective sheet, a surface of the reflective sheet close to the light guide plate is provided with blue reflective particles.

[0026] According to a second aspect of an embodiment of the present application, a display device is provided, including:

[0027] The edge-type backlight module as described in the first aspect;

[0028] The display panel is arranged opposite to the edge-entry backlight module, and the display panel is arranged on the light-emitting side of the edge-entry backlight module.

[0029] The edge-entry backlight module and display device provided in the embodiment of the present application are aimed at the existing PC light guide plate. Due to the material characteristics of the PC light guide plate, the PC light guide plate has a high absorption rate for light in the blue light band. After the light emitted by the light source enters the light guide plate from the light entrance surface, the light propagates from the side of the light guide plate close to the light source to the side far away from the light source. During the light propagation process, the light in the blue light band is continuously absorbed, and when it reaches the corresponding area far away from the light source, it is easy to cause the problem of excessive blue light absorption, which easily causes the chromaticity of the light emitted from the light exit surface of the light guide plate in this area to be yellowish, and the chromaticity of the light emitted in the near light source area is normal. The local yellow chromaticity will cause the chromaticity uniformity of the light emitted by the edge-entry backlight module to be poor. The embodiment of the present application arranges reflective particles on the optical film corresponding to the far light source area, and the reflective particles can enhance the reflectivity of light. In the far light source area, the light emitted from the light guide plate is reflected by the reflective particles and returns to the light guide plate again. The light in the blue band of the reflected light performs blue light compensation for the far light source area, and can pull the color coordinates in the far light source area from the yellowish value to the normal value. After the light in the near light source area is emitted from the light guide plate, there is no reflection enhancement by the reflective particles, but only normal reflection, thereby improving the problem of yellowish chromaticity in the far light source area and improving the chromaticity uniformity of the edge-entry backlight module. The improvement effect is more significant, which can reduce the defective rate of local yellowish chromaticity and thus reduce the waste of production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A schematic diagram of the structure of an edge-type backlight module provided in an embodiment of the present application;

[0031] Figure 2 A schematic diagram of the cross-sectional structure of an edge-lit backlight module along AA′ provided in an embodiment of the present application;

[0032] Figure 3 A schematic diagram of the structure of another edge-type backlight module provided in an embodiment of the present application;

[0033] Figure 4 A schematic diagram of the structure of another edge-lit backlight module provided in an embodiment of the present application;

[0034] Figure 5 A schematic diagram of the structure of another edge-lit backlight module provided in an embodiment of the present application;

[0035] Figure 6 A schematic diagram of the structure of an edge-type backlight module provided in an embodiment of the present application;

[0036] Figure 7 A schematic diagram of a partial structure of an edge-type backlight module provided in an embodiment of the present application;

[0037] Figure 8A schematic diagram of the structure of a display device provided in an embodiment of the present application;

[0038] Fig. 9 A schematic diagram of the partial structure of another display device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0039] In order to better understand the technical solutions provided by the embodiments of this specification, the technical solutions of the embodiments of this specification are described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of this specification and the specific features in the embodiments are detailed descriptions of the technical solutions of the embodiments of this specification, rather than limitations on the technical solutions of this specification. In the absence of conflict, the embodiments of this specification and the technical features in the embodiments can be combined with each other.

[0040] In this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or equipment. In the absence of more restrictions, the elements limited by the statement "comprise one..." do not exclude the existence of other identical elements in the process, method, article or equipment including the elements. The term "more than two" includes two or more than two situations.

[0041] In the field of display technology, edge-entry backlights are widely used in small and medium-sized displays. In the current consumer market, due to the reliability advantages of PC (polycarbonate) light guide plates, most of the light guide plates in edge-entry backlights use PC light guide plates. However, PC light guide plates can easily cause the edge-entry backlight module to turn yellow in areas far away from the light source, resulting in poor chromaticity uniformity of the light emitted by the edge-entry backlight module.

[0042] In view of this, the embodiments of the present application provide an edge-type backlight module and a display device, which can improve the yellowing problem of the existing edge-type backlight module in the area far away from the light source, so as to improve the chromaticity uniformity of the light emitted by the edge-type backlight module.

[0043] The embodiment of the present application provides an edge-type backlight module. Figure 1 A schematic diagram of the structure of an edge-type backlight module provided in an embodiment of the present application; Figure 2 This is a schematic diagram of the cross-sectional structure of an edge-lit backlight module along AA′ provided in an embodiment of the present application. Figure 1 and Figure 2 The edge-entry backlight module provided in the embodiment of the present application includes: a light source 100; a light guide plate 200, the light guide plate 200 includes a near light source area 210 and a far light source area 220, the near light source area 210 is located between the light source 100 and the far light source area 220; an optical film 300, the optical film 300 is arranged opposite to the light guide plate 200, and reflective particles 301 are arranged on the optical film 300 corresponding to the far light source area 220. Exemplarily, the light guide plate 200 can be a PC light guide plate, and the light source 100 can be an LED light bar assembled from multiple LEDs. It is easy to understand that, if Figure 2 As shown, the light emitted by the light source 100 enters the light guide plate 200 from the light incident surface 201 of the light guide plate 200, and the light in the light guide plate 200 is emitted from the light exiting surface 202. The side-incident backlight module can convert the line light source into a surface light source, and is usually used to provide a backlight source for a liquid crystal display device, and the embodiments of the present application are not specifically limited.

[0044] Exemplary, reference Figure 1 and Figure 2 If the light guide plate 200 is a PC light guide plate, due to the material properties of the PC light guide plate, the PC light guide plate has a higher absorption rate for light in the blue light band. After the light emitted by the light source 100 enters the light guide plate 200 from the light incident surface 201 of the light guide plate 200, the light propagates from the side of the light guide plate 200 close to the light source 100 to the side away from the light source 100. In this process, as the light propagates, the light in the blue light band is continuously absorbed. When it reaches the corresponding area far away from the light source 100, it is easy to cause the problem of excessive blue light absorption, which easily causes the chromaticity of the light emitted from the light exit surface 202 of the light guide plate 200 in this area to be yellowish, such as Figure 1 The chromaticity of the light emitted from the far light source area 220 is yellowish, that is, the color coordinates are close to the yellow area in the chromaticity diagram. The chromaticity of the light emitted from the near light source area 210 is normal, and the chromaticity of the light emitted from the far light source area 220 is yellowish, forming local yellowing, which will cause the chromaticity uniformity of the light emitted by the edge-entry backlight module to be poor. In response to this problem, the existing production line of the edge-entry backlight module usually formulates an interception limit sample that meets the chromaticity uniformity specification. The equipment or workers on the production line judge the side-entry backlight module products that do not meet the chromaticity uniformity specification as defective products based on the interception limit sample, and rework or scrap the defective products. This method is difficult to fundamentally solve the problem of local yellowing of the side-entry backlight module away from the light source area, and will also cause an increase in the production defect rate, slow operating efficiency, and increase production costs. The problem of local yellowing in the area away from the light source can also be improved by improving the density of the light guide plate dots, but the improvement effect is relatively limited, and the improvement in production yield is small.

[0045] Exemplary, combined Figure 1 and Figure 2In the edge-entry backlight module provided by the embodiment of the present application, the optical film 300 corresponding to the far light source area 220 is provided with reflective particles 301, and the reflective particles 301 can enhance the reflectivity of light. For example, if the optical film 300 is provided on the side where the light exiting surface 202 of the light guide plate 200 is located, the light emitted from the light guide plate 200 is reflected by the reflective particles and returns to the light guide plate 200 again, and the light in the blue band of the reflected light supplements the blue light of the far light source area 220, and can pull the color coordinates in the far light source area 220 from the yellowish value to the normal value, thereby improving the problem of the yellowish chromaticity of the far light source area 220, improving the chromaticity uniformity of the edge-entry backlight module, reducing the defective rate of the local yellowish chromaticity, and reducing the waste of production costs. It should be noted that the far light source area 220 may represent an area with a yellowish chromaticity. Specifically, the position and area of ​​the far light source area 220 may be obtained based on theoretical calculations, or by matching actual measurements with theoretical calculations. This embodiment of the present application does not specifically limit this. Figure 1 As shown, the edge of the high light source region 220 may be a partial edge of the light guide plate. Figure 3 This is a schematic diagram of the structure of another edge-lit backlight module provided in an embodiment of the present application. Figure 3 As shown, the high light source region 220 may also be surrounded by a portion of the edge of the light guide plate 200 . Figure 4 This is a schematic diagram of the structure of another edge-lit backlight module provided in an embodiment of the present application. Figure 4 As shown, the number of the high light source areas 220 can also be two or more, and the high light source areas 220 can be rectangular, circular, or elliptical, and can be obtained based on actual product measurements or theoretical calculations, and the embodiments of the present application do not make specific limitations.

[0046] The edge-entry backlight module provided in the embodiment of the present application is aimed at the existing PC light guide plate due to its material characteristics. The PC light guide plate has a high absorption rate for light in the blue light band. After the light source 100 emits light and enters the light guide plate 200 from the light entrance surface 201 of the light guide plate 200, the light propagates from the side of the light guide plate 200 close to the light source 100 to the side away from the light source 100. During the light propagation process, the light in the blue light band is continuously absorbed, and when it reaches the corresponding area far away from the light source 100, it is easy to cause the problem of excessive blue light absorption, which easily leads to the chromaticity of the light emitted from the light exit surface 202 of the light guide plate 200 in this area being yellowish. The chromaticity of the light emitted from the near light source area 210 is normal, and the local chromaticity is yellow, which will cause the chromaticity uniformity of the light emitted by the edge-entry backlight module to be poor. The embodiment of the present application arranges reflective particles 301 on the optical film 300 corresponding to the far light source area 220, and the reflective particles 301 can enhance the reflectivity of light. Then, in the far light source area 220, the light emitted from the light guide plate 200 is reflected by the reflective particles 301 and returns to the light guide plate 200 again. The light in the blue band of the reflected light performs blue light compensation for the far light source area 220, and can pull the color coordinates in the far light source area 220 from a yellowish value to a normal value. After the light in the near light source area 210 is emitted from the light guide plate 200, there is no reflection enhancement by the reflective particles 301, and only normal reflection is performed, thereby improving the problem of yellowish chromaticity in the far light source area 220 and improving the chromaticity uniformity of the edge-entry backlight module. The improvement effect is more significant, and can reduce the defective rate of local yellowish chromaticity, thereby reducing the waste of production costs.

[0047] In some embodiments, the reflectivity of the optical film 300 corresponding to the low light source region 210 for visible light is lower than the reflectivity of the optical film 300 corresponding to the high light source region 220 for visible light.

[0048] The side-entry backlight module provided in the embodiment of the present application can, under the action of the reflective particles 301, make the reflectivity of the optical film 300 corresponding to the far light source area 220 for visible light greater than the reflectivity of the optical film 300 corresponding to the near light source area 210 for visible light. In the far light source area 220, the light emitted from the light guide plate 200 is reflected by the reflective particles and returns to the light guide plate 200 again. The light in the blue band of the reflected light supplements the blue light for the far light source area 220, and can pull the color coordinates in the far light source area 220 from a yellowish value to a normal value. After the light in the near light source area 210 is emitted from the light guide plate 200, there is no reflection enhancement by the reflective particles 301, and only normal reflection is performed. Therefore, the problem of yellowish chromaticity in the far light source area 220 can be improved, the chromaticity uniformity of the side-entry backlight module can be improved, and the defective rate of local yellowish chromaticity can be reduced. Compared with the one-by-one comparison and interception of interception limit samples in the prior art, the waste of production costs can be reduced.

[0049] In some embodiments, the reflective particles are disposed on the surface of the optical film; and / or, the reflective particles are disposed inside the optical film.

[0050] Exemplarily, the reflective particles 301 can be arranged on the surface of the optical film 300 on the side close to the light guide plate 200; the reflective particles 301 can be arranged on the surface of the optical film 300 on the side away from the light guide plate 200; the reflective particles 301 can also be arranged inside the optical film 300. Alternatively, the reflective particles 301 are arranged inside and on the surface of the optical film 300. The reflective particles 301 on the surface of the optical film 300 can be arranged by bonding, and the reflective particles 301 inside the optical film 300 can be added during the preparation process of the optical film 300, which is not specifically limited in the embodiment of the present application. The reflective particles 301 on the surface of the optical film 300 will have a stronger reflective effect on visible light. Under the same reflective effect, the density of the reflective particles 301 inside the optical film 300 can be set larger. The light reflection of the reflective particles 301 on the surface of the optical film 300 on the side close to the light guide plate 200 has a more obvious effect on improving the yellowish chromaticity.

[0051] In some embodiments, in the direction from the near light source area to the far light source area, the density of the reflective particles provided on the optical film corresponding to the far light source area gradually increases. Exemplarily, since the area on the light guide plate 200 that is farther from the light source 100 is more likely to have a yellowish chromaticity, and the area on the light guide plate 200 that is farther from the light source 100 needs to be supplemented with more blue light, the density of the reflective particles 301 provided on the optical film 300 corresponding to the far light source area 220 can be gradually increased in the direction from the near light source area 210 to the far light source area 220, and the chromaticity can be improved according to the degree of yellowish chromaticity in the far light source area 220, and the improvement effect of the yellowish chromaticity is more uniform.

[0052] In some embodiments, the diameter of the reflective particles 301 may be in the range of 10-20 μm. If the diameter of the reflective particles 301 is less than 10 μm, the reflection enhancement effect is relatively limited. If the diameter of the reflective particles 301 is greater than 20 μm, it will cause obvious visible graininess of the edge-entry backlight module, affecting the light output effect of the backlight module.

[0053] Exemplarily, the reflective particles 301 may be plastic or PET (polyethylene terephthalate), the color of the reflective particles 301 may be white or transparent, and the surface of the reflective particles 301 may be coated with a coating that enhances reflection, which is not specifically limited in the present application.

[0054] Exemplarily, in the preparation process, the reflective particles 301 can be mixed in glue, and the glue mixed with the reflective particles 301 can be coated on the local surface of the optical film 300. In the assembly process of the optical film 300, the area coated with the glue containing the reflective particles 301 can be assembled corresponding to the high light source area 220 of the light guide plate 200. This is only a schematic illustration and is not specifically limited in the embodiments of the present application.

[0055] In some embodiments, the area of ​​the high light source region 220 accounts for 1 / 3-3 / 5 of the total area of ​​the light guide plate 200 .

[0056] For example, the size of the light guide plate 200 is usually close to or the same as that of the optical film 300, and the area of ​​the optical film 300 provided with the reflective particles 301 may account for 1 / 3-3 / 5 of the total area of ​​the optical film 300. The local yellowing area can be covered as much as possible to improve the local yellowing and improve the color uniformity of the light output of the edge-type backlight module.

[0057] In some embodiments, Figure 5 This is a schematic diagram of the structure of another edge-lit backlight module provided in an embodiment of the present application. Figure 5 As shown, the edge-entry backlight module provided in the embodiment of the present application may further include a plastic frame 400, which is used to fix the light guide plate 200, the optical film 300 and the light source 100; the reflectivity of the plastic frame 400 corresponding to the far light source area 220 for blue light is greater than the reflectivity of the plastic frame 400 corresponding to the near light source area 210 for blue light. For example, Figure 5As shown, the plastic frame 400 corresponding to the far light source area 220 may be the far light source plastic frame 420, and the plastic frame 400 corresponding to the near light source area 210 may be the near light source plastic frame 410, and the reflectivity of the far light source plastic frame 420 for blue light is greater than the reflectivity of the near light source plastic frame 410 for blue light. Usually, the side edges of the light guide plate 200 and the optical film 300 are clamped on the plastic frame 400, which can limit the positions of the light guide plate 200, the optical film 300 and the light source 100. Part of the light will also be emitted from the side of the light guide plate 200. The light emitted from the side of the light guide plate 200 is usually irradiated on the plastic frame 400. The plastic frame is usually made of white material. In order to improve the yellowish chromaticity problem of the far light source area 220, the reflectivity of the plastic frame 400 corresponding to the far light source area 220 for blue light can be set to be greater than the reflectivity of the plastic frame 400 corresponding to the near light source area 210 for blue light. The blue light reflected by the far light source plastic frame 420 is more than the blue light reflected by the near light source plastic frame 410, so as to supplement more blue light to the far light source area 220, pull the chromaticity of the far light source area 220 back from yellowish to the normal range, and improve the local yellowing problem of the side-entry backlight module. It should be noted that the blue light mentioned in the embodiment of the present application can be a band of blue light, and can be a plurality of blue lights of different wavelengths, which is not specifically limited in the embodiment of the present application.

[0058] The edge-entry backlight module provided in the embodiment of the present application can make the reflectivity of the rubber frame 400 corresponding to the far light source area 220 for blue light be greater than the reflectivity of the rubber frame 400 corresponding to the near light source area 210 for blue light, so that the far light source rubber frame 420 reflects more blue light than the near light source rubber frame 410, so as to supplement the far light source area 220 with more blue light. If the chromaticity of the near light source area 210 is normal, there is no need to supplement too much blue light, and the chromaticity of the far light source area 220 can be further pulled back from yellowish to a normal range, thereby strengthening the improvement of the local yellowing of the edge-entry backlight module and further improving the uniformity of the light output chromaticity of the edge-entry backlight module.

[0059] In some embodiments, for example, Figure 5 As shown, the plastic frame 400 corresponding to the low light source area 210 partially surrounds the low light source area 210, and the plastic frame 400 corresponding to the high light source area 220 partially surrounds the high light source area 220. For a backlight module product in which the chromaticity of the high light source area 220 is seriously yellowish, the three sides of the plastic frame 400 corresponding to the high light source area 220 can be set to enhance the reflectivity of blue light, so that the blue light reflection efficiency is stronger and the yellowish chromaticity problem of the high light source area 220 is better improved.

[0060] For example, Figure 6 The schematic diagram of the structure of a side-lit backlight module provided in the embodiment of the present application is shown in FIG. Figure 6As shown, one side of the plastic frame 400 corresponding to the high light source area 220 serves as the high light source plastic frame 420 , which can be used to improve the phenomenon that the chromaticity of the high light source area 220 is slightly yellowish, and the embodiment of the present application is not specifically limited thereto.

[0061] In some embodiments, the reflectivity of the plastic frame 400 corresponding to the far light source region 220 for blue light is greater than 4%. Specifically, the reflectivity of the plastic frame 400 corresponding to the far light source region 220 for blue light is 5%, which can further increase the blue light in the far light source region 220 on the basis of the improvement effect of the reflective particles 301, so as to better improve the problem of yellowish chromaticity in the far light source region 220.

[0062] In some embodiments, for example, the surface of the plastic frame 400 corresponding to the high light source area 220 is coated with a blue coating; the blue coating can be a blue paint or other blue materials, which is not specifically limited in the embodiments of the present application. This method has high requirements for the material adhesion and reliability of the blue coating, and is more flexible in adjusting the blue light reflectivity. Blue coatings of different chromaticities or different material properties can be used to adjust the blue light reflectivity.

[0063] Exemplarily, the rubber frame 400 corresponding to the high light source area 220 is doped with blue particles. The rubber frame 400 is usually prepared by an injection molding process. In the injection molding process, blue particles can be doped in the injection molding material corresponding to the high light source rubber frame 420. The blue particles can increase the reflectivity of the high light source rubber frame 420 for blue light. The high light source rubber frame 420 prepared in this way has a lower blue light reflectivity, but the process is easy to implement without adding process steps.

[0064] Exemplarily, the plastic frame 400 corresponding to the high light source area 220 can be made of blue material. That is, blue injection molding material is injected into the injection mold corresponding to the high light source plastic frame 420, so that the high light source plastic frame 420 obtained by injection molding has a large blue light reflectivity. The low light source plastic frame 410 and the high light source plastic frame 420 prepared in this way can also be integrated. The high light source plastic frame 420 prepared in this way has a large reflectivity for blue light, and it is easy to adjust different reflectivities. The existing process technology can be used without changing the mold and equipment.

[0065] In some embodiments, the optical film 300 may include a first optical film and a second optical film, wherein the first optical film is disposed on the side of the light guide plate 200 where the light exit surface 202 is located, and the second optical film is disposed on the side of the light guide plate 200 away from the light exit surface 202. The reflective particles 301 may be disposed on the optical film 300 above the light guide plate 200, or may be disposed on the optical film 300 below the light guide plate 200. The reflective particles 301 disposed on the multi-layer optical film 300 can reflect more light to the light guide plate 200, thereby improving the utilization rate of light, and supplementing more blue light to the far light source area 220, which can further improve the problem of yellowish chromaticity in the far light source area 220.

[0066] In some embodiments, the first optical film includes a first diffuser and / or a brightness enhancement film. The first diffuser is disposed on the side where the light emitting surface 202 of the light guide plate 200 is located. If the first optical film also includes a brightness enhancement film, the brightness enhancement film is disposed on the side of the first diffuser away from the light guide plate 200. The first diffuser is generally used to further uniformize the light emitted from the light guide plate 200 to obtain a surface light source with uniform brightness. The brightness enhancement film can reduce the waste of light and increase the utilization rate of light to increase the brightness of the backlight module. Reflective particles 301 are disposed on the surface of the first diffuser and the brightness enhancement film on the side close to the light guide plate 200, which can reflect more light into the light guide plate 200, supplement more blue light to the far light source area, so as to adjust the chromaticity of the far light source area 220 from yellowish to a normal chromaticity value, and further improve the problem of local yellowish chromaticity.

[0067] In some embodiments, the second optical film includes a second diffuser and / or a reflector. The second diffuser is disposed on the side of the light guide plate 200 away from the light emitting surface 202. If the second optical film also includes a reflector, the reflector is disposed on the side of the second diffuser away from the light guide plate 200. The second diffuser also functions to homogenize the light. The reflector is mainly used to reflect the light emitted from the bottom of the light guide plate 200 back into the light guide plate 200. Only the light emitted from the light emitting surface of the light guide plate 200 is effective. The light emitted from the bottom of the light guide plate 200 is regarded as the loss and waste of light. Therefore, the provision of a reflector can improve the utilization rate of the light emitted by the light source, reduce the waste of light, and improve the overall brightness of the edge-entry backlight module.

[0068] For example, Figure 7 This is a partial structural diagram of an edge-lit backlight module provided in an embodiment of the present application. Figure 7 As shown, the first optical film may include a first diffuser 310 and a prism 320, and the second optical film may include a reflector 330. The prism 320 is mainly used to homogenize light. The first optical film and the second optical film are respectively arranged on both sides of the light guide plate 200, and the plastic frame 400 is arranged on the side of the optical film of the light guide plate 200. Figure 7 The other structures and membrane materials shown are conventional settings and are not described in detail in the embodiments of the present application.

[0069] The edge-entry backlight module provided in the embodiment of the present application has reflective particles 301 arranged on the surface of one side of the multiple optical films close to the light guide plate, so as to enhance the reflectivity of the light emitted by the light guide plate 200, thereby being able to supplement sufficient blue light for the far light source area 220, and being able to more efficiently adjust the chromaticity of the far light source area 220 from yellowish to a normal chromaticity value range, thereby further improving the problem of local yellowish chromaticity.

[0070] In some embodiments, when the second optical film includes a reflective sheet, a surface of the reflective sheet 330 close to the light guide plate 200 is provided with blue reflective particles. The blue reflective particles can reflect blue light, and the blue reflective particles can be prepared with reference to the reflective particles 301 mentioned in the above embodiment, or a blue coating can be coated on the surface of the reflective particles 301 to reflect blue light, or the blue reflective particles can be prepared with a blue material, which is not specifically limited in the embodiment of the present application.

[0071] The edge-lit backlight module provided in the embodiment of the present application has blue reflective particles arranged on the surface of the reflective sheet 330 close to the light guide plate 200, thereby enhancing the reflectivity of the blue light in the light emitted from the light guide plate 200 away from the light emitting surface 202, and enhancing the utilization rate of the blue light in the light emitted from the bottom of the light guide plate 200. The supplement of the blue light in the far light source area 220 is further increased, and the chromaticity of the far light source area 220 is further efficiently adjusted from yellowish to a normal chromaticity value range, further improving the problem of local yellowish chromaticity.

[0072] According to a second aspect of the embodiments of the present application, a display device is provided. Figure 8 This is a schematic diagram of the structure of a display device provided in an embodiment of the present application. Figure 8 As shown, the display device provided in the embodiment of the present application includes:

[0073] As described in the first aspect, the edge-entry backlight module 1000 and the display panel 2000 are arranged opposite to the edge-entry backlight module 1000, and the display panel 2000 is arranged on the light-emitting side 1100 of the edge-entry backlight module 1000. The display panel 2000 can be a liquid crystal display panel, and the edge-entry backlight module 1000 provides a backlight source for the display panel 2000.

[0074] For example, Fig. 9 This is a partial structural diagram of another display device provided in an embodiment of the present application. Fig. 9As shown, the display panel 2000 is arranged on the light-emitting side of the edge-type backlight module, a polarizer 3000 may be arranged on the side of the display panel 2000 away from the edge-type backlight module, a cover plate 5000 may be arranged on the side of the polarizer 3000 away from the display panel 2000, and the cover plate 5000 and the polarizer 3000 may be bonded together by a transparent optical adhesive 4000. The display device provided in the embodiment of the present application may further include a back plate 500, which is used to provide strength protection and support for the edge-type backlight module. Fig. 9 It is only for illustration and is not intended to be a specific limitation of the embodiments of the present application. Fig. 9 The other structures of the display device shown are conventional settings and are not described in detail in the embodiments of the present application.

[0075] It should be noted that the display device provided in the embodiment of the present application can be a smart phone, a laptop computer, a tablet computer, a computer host display, a game console, a television, etc., and the embodiment of the present application does not make any specific limitation.

[0076] The display device provided by the embodiment of the present application is aimed at the existing PC light guide plate. Due to the material characteristics of the PC light guide plate, the PC light guide plate has a high absorption rate for light in the blue light band. After the light emitted by the light source enters the light guide plate from the light incident surface of the light guide plate, the light propagates from the side of the light guide plate close to the light source to the side far away from the light source. During the light propagation process, the light in the blue light band is continuously absorbed, and when it reaches the corresponding area far away from the light source, it is easy to cause the problem of excessive blue light absorption, which easily causes the chromaticity of the light emitted from the light exit surface of the light guide plate in this area to be yellowish, and the chromaticity of the light emitted from the near light source area is normal. The local yellow chromaticity will cause the chromaticity uniformity of the light emitted by the side-entry backlight module to be poor. The side-entry backlight module adopted by the embodiment of the present application is provided with reflective particles on the optical film corresponding to the far light source area. The reflective particles are provided on the surface of the optical film close to the light guide plate, and the reflective particles can enhance the reflectivity of light. In the far light source area, the light emitted from the light guide plate is reflected by the reflective particles and returns to the light guide plate again. The light in the blue band of the reflected light performs blue light compensation for the far light source area, and can pull the color coordinates in the far light source area from the yellowish value to the normal value. After the light in the near light source area is emitted from the light guide plate, there is no reflection enhancement by the reflective particles, but only normal reflection, thereby improving the problem of yellowish chromaticity in the far light source area, improving the chromaticity uniformity of the edge-entry backlight module, and further improving the chromaticity uniformity of the display device, which can improve the display effect of the display device.

[0077] Although the preferred embodiments of this specification have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of this specification.

[0078] Obviously, those skilled in the art can make various changes and modifications to this specification without departing from the spirit and scope of this specification. Thus, if these modifications and variations of this specification fall within the scope of the claims of this specification and their equivalents, this specification is also intended to include these modifications and variations.

Claims

1. A side-lit backlight module, characterized in that: include: light source; A light guide plate, the light guide plate comprising a low light source area and a high light source area, the low light source area being located between the light source and the high light source area; An optical film, the optical film is arranged opposite to the light guide plate, and reflective particles are arranged on the optical film corresponding to the high light source area; The optical film comprises a first optical film and a second optical film, wherein the first optical film is arranged on a side where the light emitting surface of the light guide plate is located, and the second optical film is arranged on a side of the light guide plate away from the light emitting surface; The first optical film includes a first diffuser and / or a brightness enhancement film; The second optical film comprises a reflective sheet, and a surface of the reflective sheet close to the light guide plate is provided with blue reflective particles, and the blue reflective particles are prepared by coating a blue coating on the surface of the reflective particles or using a blue material; In the direction from the low light source area to the high light source area, the density of the reflective particles arranged on the optical film corresponding to the high light source area gradually increases; The edge-type backlight module further includes a plastic frame, and the plastic frame is used to fix the light guide plate, the optical film and the light source; The reflectivity of the plastic frame corresponding to the high light source area to blue light is greater than the reflectivity of the plastic frame corresponding to the low light source area to blue light; The surface of the rubber frame corresponding to the high light source area is coated with a blue coating; or, The plastic frame corresponding to the high light source area is doped with blue particles; or, The rubber frame corresponding to the high light source area is made of blue material.

2. The edge-lit backlight module according to claim 1, characterized in that: The reflectivity of the optical film corresponding to the low light source area to visible light is smaller than the reflectivity of the optical film corresponding to the high light source area to visible light.

3. The edge-lit backlight module according to claim 1, characterized in that: The reflective particles are arranged on the surface of the optical film; and / or, The reflective particles are arranged inside the optical film.

4. The edge-lit backlight module according to claim 1, characterized in that: The diameter of the reflective particles is in the range of 10-20 μm.

5. The edge-lit backlight module according to claim 1, characterized in that: The ratio of the area of ​​the high light source region to the total area of ​​the light guide plate is in the range of 1 / 3-3 / 5.

6. The edge-lit backlight module according to claim 1, characterized in that: The portion of the plastic frame corresponding to the low light source area surrounds the low light source area, and the portion of the plastic frame corresponding to the high light source area surrounds the high light source area.

7. The edge-lit backlight module according to claim 1, characterized in that: The reflectivity of the rubber frame corresponding to the high light source area to blue light is greater than 4%.

8. The edge-lit backlight module according to claim 1, characterized in that: The second optical film includes a second diffusion sheet.

9. A display device, characterized in that: include: The edge-lit backlight module according to any one of claims 1 to 8; The display panel is arranged opposite to the edge-entry backlight module, and the display panel is arranged on the light-emitting side of the edge-entry backlight module.

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