A diffusion plate and a backlight module

Abstract

The present invention discloses a diffusion plate and a backlight module. The diffusion plate is used for diffusing a point light source. The diffusion plate includes an upper diffusion plate and a lower diffusion plate arranged parallel to the upper diffusion plate. An optical structure for uniformly diffusing the light emitted by the point light source to form a surface light source is provided on the upper diffusion plate. The optical structure includes: a first light-emitting surface in an arc shape, a second light-emitting surface arranged obliquely, and a third light-emitting surface arranged horizontally; the first light-emitting surface, the second light-emitting surface, and the third light-emitting surface are connected upward in sequence, and the first light-emitting surface protrudes upward, and the bottom of the first light-emitting surface is arranged above the point light source. By means of the optical structure, the light emitted by the point light source can form a uniform surface light source, so as to achieve the effect of zero OD value when adopting the direct-lit scheme, and can greatly reduce the cost.

Description

Technical Field

[0001] The present invention relates to the technical field of liquid crystal display, and particularly relates to a diffuser plate and a backlight module. Background Art

[0002] Currently, a direct - type scheme is usually adopted to implement a small OD (optical density) value module. The backlight module generally adopts the method of LED + lens + diffuser plate + film, or by increasing the number of LEDs and reducing the LED arrangement pitch, that is, arranging more LEDs + diffuser plate + film to implement the direct - type scheme. However, the above - mentioned methods have certain defects, such as high costs and only being able to implement small OD value schemes. Summary of the Invention

[0003] Embodiments of the present invention provide a diffuser plate and a backlight module, aiming to achieve the effect of zero OD value when adopting the direct - type scheme.

[0004] Embodiments of the present invention provide a diffuser plate for diffusing point light sources. The diffuser plate includes an upper diffuser plate and a lower diffuser plate arranged in parallel with the upper diffuser plate. The upper diffuser plate is provided with an optical structure for uniformly diffusing the light emitted by the point light source to form a surface light source. The optical structure includes: a first light - emitting surface in an arc shape, a second light - emitting surface arranged obliquely, and a third light - emitting surface arranged horizontally;

[0005] The first light - emitting surface, the second light - emitting surface, and the third light - emitting surface are connected upward in sequence, and the first light - emitting surface protrudes upward. The bottom of the first light - emitting surface is arranged above the point light source.

[0006] Further, a plurality of point light sources are provided, and each point light source corresponds to 2 optical structures. The 2 optical structures are symmetrically arranged above the point light source.

[0007] Further, the upper diffuser plate is further provided with a fourth light - emitting surface connected to the third light - emitting surface. The fourth light - emitting surface is arranged horizontally and its surface is a particle structure.

[0008] Further, the lower diffuser plate includes a fifth light - emitting surface arranged horizontally and its surface is a particle structure.

[0009] Further, the arc angle of the first light - emitting surface is 40° - 50°.

[0010] Further, the inclination angle of the second light - emitting surface is 15° - 20°.

[0011] Further, the proportion of the first light-emitting surface in the light-emitting surface of the optical structure is 40% to 60%, the proportion of the second light-emitting surface in the light-emitting surface of the optical structure is 30% to 40%, and the proportion of the third light-emitting surface in the light-emitting surface of the optical structure is 10% to 20%.

[0012] Further, the reflectivity of the first light-emitting surface is 80% to 90%.

[0013] Further, the reflectivity of the second light-emitting surface is 30% to 40%.

[0014] An embodiment of the present invention further provides a backlight module, which includes the diffusion plate as described above.

[0015] An embodiment of the present invention provides a diffusion plate and a backlight module. The diffusion plate is used to diffuse a point light source. The diffusion plate includes an upper diffusion plate and a lower diffusion plate arranged in parallel with the upper diffusion plate. An optical structure for uniformly diffusing the light emitted by the point light source to form a surface light source is provided on the upper diffusion plate. The optical structure includes: a first light-emitting surface in an arc shape, a second light-emitting surface arranged obliquely, and a third light-emitting surface arranged horizontally; the first light-emitting surface, the second light-emitting surface, and the third light-emitting surface are sequentially connected upward, and the first light-emitting surface protrudes upward, and the bottom of the first light-emitting surface is arranged above the point light source. Through the optical structure on the diffusion plate in the embodiment of the present invention, the light emitted by the point light source can form a uniform surface light source, so as to achieve the effect of zero OD value when adopting the direct-lit scheme, and can greatly reduce the cost. Description of the Drawings

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0017] Figure 1 It is a schematic structural diagram of a diffusion plate provided by an embodiment of the present invention;

[0018] Figure 2 It is a schematic structural diagram of a backlight module provided by an embodiment of the present invention. Detailed Embodiments

[0019] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0020] It should be understood that when used in this specification and the appended claims, the terms "comprises" and "comprising" indicate the presence of the described features, wholes, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or their combinations.

[0021] It should also be understood that the terms used in this specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in this specification of the present invention and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an", and "the" are intended to include the plural forms.

[0022] It should be further understood that the term "and / or" used in this specification of the present invention and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0023] Please refer to the following Figure 1 , a diffusion plate provided by an embodiment of the present invention is used to diffuse a point light source 3. The diffusion plate includes an upper diffusion plate 1 and a lower diffusion plate 2 arranged in parallel with the upper diffusion plate 1. An optical structure 11 for uniformly diffusing the light emitted by the point light source 3 to form a surface light source is provided on the upper diffusion plate 1. The optical structure 11 includes: a first light-emitting surface 111 in an arc shape, a second light-emitting surface 112 arranged obliquely, and a third light-emitting surface 113 arranged horizontally;

[0024] The first light-emitting surface 111, the second light-emitting surface 112, and the third light-emitting surface 113 are sequentially connected upward, and the first light-emitting surface 111 protrudes upward. The bottom of the first light-emitting surface 111 is arranged above the point light source 3.

[0025] In this embodiment, after the point light source 3 emits light, a part of the light is emitted onto the first light-emitting surface 111, and is reflected or refracted on the first light-emitting surface 111. For the reflected light, it can be reflected onto the lower diffusion plate 2. For the refracted light, it can be refracted onto the upper diffusion plate 1 or the third light-emitting surface 113. Another part of the light is emitted onto the second light-emitting surface 112, and is reflected or refracted on the second light-emitting surface 112. For the reflected light, it can be reflected onto the lower diffusion plate 3. For the refracted light, it can be refracted onto the upper diffusion plate 1. Still another part of the light is directly emitted onto the third light-emitting surface 113, and is reflected or refracted on the third light-emitting surface 113. For the reflected light, it can be reflected onto the lower diffusion plate 2. For the refracted light, it can be refracted onto the upper diffusion plate 1.

[0026] Through the optical structure 11 in this embodiment, that is, after the above-mentioned light reflection or refraction process, the light-emitting angle of the point light source 3 can be enlarged, that is, the light emitted by the point light source 3 is changed into a uniform surface light source, and thus the direct-lit zero OD value scheme can be truly realized. At the same time, the cost can be greatly saved and the production process can be simplified.

[0027] In a specific embodiment, the material of the diffusion plate 1 in this embodiment is polystyrene-based plastic. Of course, in other embodiments, the diffusion plate 1 can also adopt other materials that can be processed into the optical structure, such as silica gel, glass, PMMA (polymethyl methacrylate), PC (polycarbonate), PP (polypropylene), PET (polyester resin), etc.

[0028] In an embodiment, a plurality of point light sources 3 are provided, and each point light source 3 corresponds to 2 optical structures 11, and the 2 optical structures 11 are symmetrically arranged above the point light source 3.

[0029] In this embodiment, 2 optical structures 11 are symmetrically arranged above the point light source 3, that is, 2 first light-emitting surfaces 111, 2 second light-emitting surfaces 112, and 2 third light-emitting surfaces 113 are symmetrically arranged above the point light source 3. The advantage of such an arrangement is that the light emitted by the point light source 3 can reach all areas of the upper diffusion plate 1 more evenly. In addition, in an actual scenario, the number of point light sources 3 is usually multiple. Therefore, the number of optical structures 11 is also set to be multiple, and the number of optical structures 11 is twice the number of point light sources 3.

[0030] In one embodiment, a fourth light-emitting surface 114 connected to the third light-emitting surface 113 is further provided on the upper diffusion plate 1, and the fourth light-emitting surface 114 is horizontally arranged and its surface has a particle structure.

[0031] In this embodiment, a fourth light-emitting surface 114 with a particle-structured surface is provided on the upper diffusion plate 1. In this way, the light emitted by the point light source 3 and the light reflected by the first light-emitting surface 111 can be reflected again after hitting the fourth light-emitting surface 114 and then reflected to the lower diffusion plate 2, so that the light emitted by the point light source 3 can be more evenly distributed.

[0032] In one embodiment, the lower diffusion plate 2 includes a fifth light-emitting surface 21 that is horizontally arranged and has a particle structure on its surface.

[0033] In this embodiment, a fifth light-emitting surface 21 with a particle-structured surface is provided on the lower diffusion plate 2. When the light reflected by the first light-emitting surface 111, the second light-emitting surface 112, the third light-emitting surface 113, and the fourth light-emitting surface 114 hits the lower diffusion plate 2, the amount of light refracted out by the lower diffusion plate 2 can be reduced, and most of the light can be reflected again by the fifth light-emitting surface 21 to the fourth light-emitting surface 114. In this way, after multiple reflections, the light can be reflected to a position farther away from the point light source 3, and the reflected light can be evenly distributed, thereby improving the effect of evenly diffusing the light emitted by the point light source and forming a surface light source.

[0034] In one embodiment, the arc angle of the first light-emitting surface 111 is 40° to 50°.

[0035] In this embodiment, the arc angle of the first light-emitting surface 111 is set to 40° to 50°. The arc angle refers to the angle between the line connecting the two endpoints of the first light-emitting surface 111 and the horizontal plane. In this way, the first light-emitting surface 111 can receive and reflect more light emitted by the point light source 3. In a specific embodiment, the arc angle of the first light-emitting surface 111 is 45°.

[0036] In one embodiment, the inclination angle of the second light-emitting surface 112 is 15° to 20°.

[0037] In this embodiment, the inclination angle of the second light-emitting surface 112 (i.e., the angle between the second light-emitting surface 112 and the horizontal plane) is set to 15° to 20°, so that the second light-emitting surface 112 can receive and reflect more light emitted by the point light source 3. In a specific embodiment, the inclination angle of the second light-emitting surface 112 is 18°.

[0038] In one embodiment, the proportion of the first light-emitting surface 111 in the light-emitting surface of the optical structure 11 is 40% to 60%, the proportion of the second light-emitting surface 112 in the light-emitting surface of the optical structure 11 is 30% to 40%, and the proportion of the third light-emitting surface 113 in the light-emitting surface of the optical structure 11 is 10% to 20%.

[0039] In this embodiment, the first light-emitting surface 111, the second light-emitting surface 112, and the third light-emitting surface 113 are respectively set in a certain proportion, so that the optical structure 11 can better uniformly diffuse the light emitted by the point light source 3 to form a surface light source, and the light emitted by the obtained surface light source is more uniform. The light-emitting surface of the optical structure 11 is the total area of the first light-emitting surface 111, the second light-emitting surface 112, and the third light-emitting surface 113. In a specific embodiment, the proportion of the first light-emitting surface 111 in the light-emitting surface of the optical structure 11 (i.e., the area proportion, the same below) is 50%, the proportion of the second light-emitting surface 112 in the light-emitting surface of the optical structure 11 is 35%, and the proportion of the third light-emitting surface 113 in the light-emitting surface of the optical structure 11 is 15%.

[0040] In another embodiment, the proportion of the light received by the first light-emitting surface 111 in the total light emitted by the point light source 3 is 40% to 60%, the proportion of the light received by the second light-emitting surface 112 in the total light emitted by the point light source 3 is 30% to 40%, and the proportion of the light received by the third light-emitting surface 113 in the total light emitted by the point light source 3 is 10% to 20%. In a specific embodiment, the proportion of the light received by the first light-emitting surface 111 in the total light emitted by the point light source 3 is 50%, the proportion of the light received by the second light-emitting surface 112 in the total light emitted by the point light source 3 is 35%, and the proportion of the light received by the third light-emitting surface 113 in the total light emitted by the point light source 3 is 15%.

[0041] In one embodiment, the reflectivity of the first light-emitting surface 111 is 80% to 90%.

[0042] Since the reflectivity (or refractive index) of the light-emitting surface is related to the material of the light-emitting surface, and the material of the light-emitting surface in this embodiment is polystyrene-based plastic, therefore, the reflectivity of the first light-emitting surface 111 described in this embodiment is 80% to 90%. Correspondingly, the refractive index of the first light-emitting surface 111 is 10% to 20%. Of course, in other embodiments, if other materials are used for the light-emitting surface, the light-emitting surface has corresponding reflectivity (or refractive index).

[0043] In one embodiment, the reflectivity of the second light-emitting surface 112 is 30% to 40%.

[0044] Similarly, since the material of the light-emitting surface in this embodiment is polystyrene-based plastic, the reflectivity of the second light-emitting surface 112 described in this embodiment is 30% to 40%, and correspondingly, the refractive index of the second light-emitting surface 112 is 60% to 70%.

[0045] As Figure 2 shown, an embodiment of the present invention further provides a backlight module, including the diffusion plate described above.

[0046] The backlight module described in this embodiment can use fewer LEDs + diffusion plates + films to achieve module backlight by adopting the diffusion plate optical structure, thus greatly saving production costs and simplifying the production process. It can truly implement the direct-lit zero OD value solution and make the direct-lit module into an ultra-thin product, which not only improves the grade and aesthetics of the product, but also further enhances the user's viewing experience.

[0047] The various embodiments in the specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same or similar parts among the various embodiments can be referred to each other. For the system disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the description of the method part. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle of this application, several improvements and modifications can be made to this application, and these improvements and modifications also fall within the protection scope of the claims of this application.

[0048] It should also be noted that in this specification, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without more limitations, the element defined by the statement "including a..." does not exclude the existence of additional identical elements in the process, method, article or device including the said element.

Claims

1. A diffuser plate for diffusing a point light source, characterized in that, The diffusion plate includes an upper diffusion plate and a lower diffusion plate arranged parallel to the upper diffusion plate. An optical structure for uniformly diffusing the light emitted by a point light source to form a surface light source is provided on the upper diffusion plate. The optical structure includes: a first light-emitting surface with an arc shape, a second light-emitting surface arranged obliquely, and a third light-emitting surface arranged horizontally; The first light-emitting surface, the second light-emitting surface, and the third light-emitting surface are sequentially connected upward, and the first light-emitting surface protrudes upward. The bottom of the first light-emitting surface is arranged above the point light source; A fourth light-emitting surface connected to the third light-emitting surface is further provided on the upper diffusion plate. The fourth light-emitting surface is arranged horizontally and its surface has a particle structure; The arc angle of the first light-emitting surface is 40° to 50°; The inclination angle of the second light-emitting surface is 15° to 20°; The proportion of the first light-emitting surface in the light-emitting surface of the optical structure is 40% to 60%, the proportion of the second light-emitting surface in the light-emitting surface of the optical structure is 30% to 40%, and the proportion of the third light-emitting surface in the light-emitting surface of the optical structure is 10% to 20%.

2. The diffusion plate according to claim 1, wherein A plurality of point light sources are provided, and each point light source corresponds to two optical structures. The two optical structures are symmetrically arranged above the point light source.

3. The diffusion plate according to claim 1 or 2, characterized in that, The lower diffusion plate includes a fifth light-emitting surface arranged horizontally and having a particle structure on its surface.

4. The diffusion plate according to claim 1 or 2, characterized in that, The reflectivity of the first light-emitting surface is 80% to 90%.

5. The diffusion plate according to claim 1 or 2, characterized in that, The reflectivity of the second light-emitting surface is 30% to 40%.

6. A backlight module, characterized in that, It includes the diffusion plate according to any one of claims 1 to 5.

Images