Waveguide cover plate and display device

Abstract

The present application provides a waveguide cover plate and a display device. The waveguide cover plate includes a plurality of light guiding regions and a plurality of annular units. Each annular unit surrounds a light guiding region, and the position of the light guiding region can correspond to the position of a pixel or a sub-pixel of the display panel. The light guiding region includes a plurality of first light guiding structures, and the annular unit is formed by enclosing a plurality of second light guiding structures. The second light guiding structure includes a light absorbing layer. The display device includes a display panel and a waveguide cover plate. The waveguide cover plate and the display device provided by the present application transfer the image displayed by the display panel from the surface of the display panel facing the light emitting side to the surface of the waveguide cover plate facing the light emitting side through the first light guiding structure and the second light guiding structure, and absorb a part of the light rays emitted from the pixel with an emission angle greater than the maximum light receiving angle through the light absorbing layer of the second light guiding structure, thereby facilitating the solution of the technical problem that the large-angle light rays emitted from the pixel will cause crosstalk to the light rays propagating in the adjacent light guiding structures.

Description

Technical Field

[0001] This application belongs to the field of display technology, and more specifically, relates to a waveguide cover plate and a display device. Background Art

[0002] With the development of science and technology, electronic display screens (including LCD (liquid crystal display), OLED (organic electroluminescent display), MicroLED (micron-scale light-emitting diode array) display screens, etc.) have gradually replaced paper printed products and become the most commonly used information acquisition medium. Compared with paper printed products such as books, electronic display devices have many advantages in reading. For example, they can emit light actively, can ensure normal reading in a dark environment, and can display a rich variety of resources. However, the disadvantages of existing electronic display screens are also very obvious. When a person's eyes view a display screen, the image seen on the display screen is located below the glass cover plate and has a certain depth of field. The user can clearly feel that the picture is inside the display screen, which affects the user's viewing experience.

[0003] To solve the above problems, in the related art, an optical fiber panel is used to replace the traditional glass cover plate. Through the image transmission function of the optical fiber panel, the image displayed on the display panel is transferred from the light incident side of the optical fiber panel to the light exiting side of the optical fiber panel, so that the picture is displayed on the surface of the optical fiber panel facing the light exiting side. However, since there is a distance between the pixel layer of the display panel and the optical fiber panel, light rays with a large angle (an emission angle greater than the maximum light receiving angle of the optical fiber) emitted by the pixels will enter the adjacent light guiding structure, resulting in a crosstalk phenomenon and a decrease in the clarity of the picture displayed by the display device. Summary of the Invention

[0004] The waveguide cover plate and display device provided by the embodiments of this application are used to solve the technical problem that light rays with a large angle emitted by pixels will cause crosstalk to the light rays propagating in adjacent light guiding structures.

[0005] The basic concept proposed by the inventors of this application is: adding a light guiding structure with a light absorbing function in the optical fiber panel, and absorbing the light rays with a large angle emitted by the pixels through the light guiding structure with a light absorbing function to improve the clarity of the picture displayed by the display device.

[0006] Based on the above basic concept, an embodiment of the present application provides a waveguide cover plate, which includes a plurality of light guiding regions and a plurality of annular units. Each of the annular units surrounds one of the light guiding regions. The position of the light guiding region can correspond to the position of a pixel or a sub-pixel of a display panel, and the length of the longest side of the light guiding region is less than or equal to the length of the longest side of the pixel or the sub-pixel, and the width of the widest side of the light guiding region is less than or equal to the width of the widest side of the pixel or the sub-pixel. The light guiding region includes a plurality of first light guiding structures, and the annular unit is formed by enclosing a plurality of second light guiding structures. The first light guiding structure and the second light guiding structure can transfer the image on the light incident side of the waveguide cover plate to the light exit side of the waveguide cover plate, and the second light guiding structure includes a light absorbing layer.

[0007] In some embodiments, the first light guiding structure includes a first core and a first cladding. The refractive index of the first core is greater than that of the first cladding, and the first cladding surrounds the periphery of the first core; the second light guiding structure further includes a second core and a second cladding. The refractive index of the second core is greater than that of the second cladding, and the second cladding surrounds the periphery of the second core. The light absorbing layer surrounds the periphery of the second cladding.

[0008] In some embodiments, the light absorbing layer is an optical coating layer or a colored glass layer.

[0009] In some embodiments, the diameter of the first core is more than 3 times the thickness of the first cladding, the diameter of the second core is more than 3 times the thickness of the second cladding, and the thickness of the light absorbing layer is less than or equal to the thickness of the second cladding.

[0010] In some embodiments, the cross-sectional profiles of both the first light guiding structure and the second light guiding structure are circular.

[0011] In some embodiments, the enclosed area of the annular unit includes a plurality of voids, and the voids are unfilled or filled with a cladding material.

[0012] In some embodiments, the outer contour of the light guiding region is rectangular or hexagonal.

[0013] In some embodiments, the cross-sectional area of the first light guiding structure is one-twentieth to one-fifth of the area of the pixel; and / or the cross-sectional area of the second light guiding structure is equal to the cross-sectional area of the first light guiding structure.

[0014] An embodiment of the present application further provides a display device, which includes a display panel and the above-mentioned waveguide cover plate, and the waveguide cover plate is located on the light exit side of the display panel.

[0015] In some embodiments, the waveguide cover plate is adhered to the surface of the display panel facing the light-emitting side through an optical adhesive, and the thickness of the optical adhesive is 10 to 200 micrometers.

[0016] The waveguide cover plate and the display device provided by the embodiments of the present application transfer the image displayed by the display panel from the surface of the display panel facing the light-emitting side to the surface of the waveguide cover plate facing the light-emitting side through the first light guide structure and the second light guide structure, and absorb a part of the light rays emitted from the pixel with an emission angle greater than the maximum light-receiving angle of the first light guide structure or the maximum light-receiving angle of the second light guide structure through the light-absorbing layer of the second light guide structure, thereby facilitating the solution of the technical problem that the large-angle light rays emitted from the pixel will cause crosstalk to the light rays propagating in the adjacent light guide structures, effectively reducing the occurrence of the crosstalk phenomenon, and facilitating the improvement of the clarity of the picture displayed by the display device. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0018] Figure 1 It is a partial top view schematic diagram of the waveguide cover plate provided by some embodiments of the present application;

[0019] Figure 2 It is a partial top view schematic diagram of the waveguide cover plate provided by other embodiments of the present application;

[0020] Figure 3 For Figure 1 It is a schematic cross-sectional view in the I-I direction;

[0021] Figure 4 It is a partial cross-sectional view schematic diagram of the display device provided by some embodiments of the present application.

[0022] Among them, the reference numerals in the drawings:

[0023] 1—display device;

[0024] 10—waveguide cover plate, 11—first light guide structure, 12—second light guide structure, 100—void, 101—light guide region, 102—ring unit, 111—first core, 112—first cortex, 121—second core, 122—second cortex, 123—light-absorbing layer, L1, L2—lengths of the longest parts of the light guide region, W1, W2—widths of the widest parts of the light guide region, θ—maximum light-receiving angle of the second light guide structure;

[0025] 20 - Display panel, 21 - Upper polarizer, 22 - Upper glass substrate, 23 - Black matrix, 24 - Photoresist layer, 25 - Liquid crystal layer, 26 - Pixel circuit layer, 27 - Lower glass substrate, 28 - Lower polarizer, α - Exit angle;

[0026] 30 - Backlight module;

[0027] 40 - Optical adhesive. Specific embodiments

[0028] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present application.

[0029] Referring to "embodiment" or "embodiment" herein means that a specific feature, structure, or characteristic described in connection with the embodiment or embodiment can be included in at least one embodiment of the present application. The phrase appearing in various positions in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly or implicitly understand that the embodiments described herein can be combined with other embodiments.

[0030] It should be noted that when a component is referred to as "fixed on" or "disposed on" another component, it can be directly on the other component or indirectly on the other component. When a component is referred to as "connected to" another component, it can be directly or indirectly connected to the other component.

[0031] The orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for convenience of description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation of this patent. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0032] The meaning of the term "plurality" is two or more, unless otherwise specifically defined.

[0033] Please refer to Figure 1 , Figure 3 and Figure 4 , where Figure 1 is a partial top view schematic diagram of a waveguide cover plate provided in some embodiments of the present application, Figure 3 is Figure 1 a schematic cross-sectional view in the I-I direction inFigure 4 A cross-sectional schematic diagram of a display device provided by some embodiments of the present application. The display device 1 provided by the present application includes a waveguide cover plate 10 and a display panel 20; wherein, the display panel 20 is a liquid crystal panel or an organic light-emitting diode (OLED) panel, capable of displaying images, and the images displayed by the display panel 20 are composed of multiple pixels, and each pixel is at least composed of a sub-pixel emitting red light, a sub-pixel emitting green light, and a sub-pixel emitting blue light; the waveguide cover plate 10 is located on the light-emitting side of the display panel 20 and can protect the light-emitting surface of the display panel 20.

[0034] Specifically, taking the display panel 20 as a liquid crystal panel as an example, the display panel 20 sequentially includes an upper polarizer 21, an upper glass substrate 22, a black matrix 23, a photoresist layer 24, a liquid crystal layer 25, a pixel circuit layer 26, a lower glass substrate 27, and a lower polarizer 28 from the side close to the waveguide cover plate 10 to the side far from the waveguide cover plate 10. The pixels of the display panel 20 are formed on the surface of the upper glass substrate 22 facing the photoresist layer 24; the waveguide cover plate 10 includes a plurality of light guide regions 101 and a plurality of annular units 102. Among them, each annular unit 102 surrounds a light guide region 101, and the position of the light guide region 101 corresponds to the position of the pixel or sub-pixel of the display panel 20, that is, one light guide region 101 corresponds to one pixel or one sub-pixel, and each pixel or each sub-pixel is covered by a light guide region 101 above, and the length L1 of the longest part of the light guide region 101 is less than or equal to the length of the longest part of the pixel or the length of the longest part of the sub-pixel, and the width W1 of the widest part of the light guide region 101 is less than or equal to the width of the widest part of the pixel or the width of the widest part of the sub-pixel. That is, assuming that the length of the longest part of the pixel or sub-pixel is L and the width of the widest part is W, then the length L1 of the longest part of the light guide region 101 ≤ L, and the width W1 of the widest part of the light guide region 101 ≤ W. In the present application, the light guide region 101 includes a plurality of first light guide structures 11, and the annular unit 102 is formed by enclosing a plurality of second light guide structures 12. The first light guide structure 11 and the second light guide structure 12 can transfer the image on the light-incident side of the waveguide cover plate 10 to the light-emitting side of the waveguide cover plate 10, and the second light guide structure 12 includes an absorbing layer 123, and the absorbing layer 123 is used to absorb the light with an exit angle α greater than the maximum light-receiving angle.

[0035] It can be understood that the first light guide structure 11 and the second light guide structure 12 are respectively two optical fiber slices with different structures; the "maximum light receiving angle" refers to the half angle of the light receiving cone angle. Only the light rays entering the optical fiber along a specific light receiving cone angle can propagate along the optical fiber. In this application, the "maximum light receiving angle" refers to both the maximum light receiving angle of the first light guide structure 11 and the maximum light receiving angle θ of the second light guide structure 12. When the exit angle α of the light rays emitted from the pixel is greater than the maximum light receiving angle of the first light guide structure 11 or the maximum light receiving angle θ of the second light guide structure 12, a part of the light rays emitted from the pixel will be absorbed by the light absorbing layer 123 of the second light guide structure 12; when the display panel 20 is a liquid crystal panel, the backlight module 30 is required to provide illumination for the display panel 20. The backlight module 30 is located on the light incident side of the display panel 20 and is disposed close to the lower polarizer 28.

[0036] The display device 1 provided by the above embodiment adopts the waveguide cover plate 10, and transfers the image displayed by the display panel 20 from the surface of the display panel 20 facing the light emitting side to the surface of the waveguide cover plate 10 facing the light emitting side through the first light guide structure 11 and the second light guide structure 12, and absorbs a part of the light rays with the exit angle α greater than the maximum light receiving angle of the first light guide structure 11 or the maximum light receiving angle θ of the second light guide structure 12 emitted from the pixel through the light absorbing layer 123 of the second light guide structure 12, thereby facilitating the solution of the technical problem that the large angle light rays emitted from the pixel will cause crosstalk to the light rays propagating in the adjacent light guide structure, effectively reducing the occurrence of the crosstalk phenomenon, and being beneficial to improving the clarity of the picture displayed by the display device 1.

[0037] In some embodiments, as Figure 4 shown, the waveguide cover plate 10 is adhered to the surface of the display panel 20 facing the light emitting side through the optical adhesive 40, and the thickness of the optical adhesive 40 is 10 - 200 microns. That is, an optical adhesive layer is provided between the surface of the display panel 20 facing its light emitting side and the waveguide cover plate 10. Specifically, the thickness of the optical adhesive 40 is 10 - 200 microns. Among them, when the thickness of the optical adhesive 40 is 50 microns, the influence on the display effect of the display device 1 is relatively small.

[0038] In some embodiments, as Figure 1 and Figure 3As shown, the first light guiding structure 11 includes a first core 111 and a first cladding 112. Among them, the refractive index of the first core 111 is greater than that of the first cladding 112, and the first cladding 112 surrounds the first core 111; the second light guiding structure 12 further includes a second core 121 and a second cladding 122. Among them, the refractive index of the second core 121 is greater than that of the second cladding 122, the second cladding 122 surrounds the second core 121, and the light absorbing layer 123 surrounds the second cladding 122. Specifically, the first core 111, the first cladding 112, the second core 121, and the second cladding 122 can be made of silica material (glass) or binary mixture materials such as ZrF4, LaF3, and BaF2 (fluoride glass), etc. That is, the first core 111 and the second core 121 are respectively glass rods, the first cladding 112 and the second cladding 122 are respectively glass tubes, the first core 111 is inserted into the first cladding 112, the second core 121 is inserted into the second cladding 122, the refractive indices of the first core 111 and the second core 121 are preferably 1.56 - 2.3 respectively, and the refractive indices of the first cladding 112 and the second cladding 122 are preferably 1.45 - 1.55 respectively, so as to ensure that the light incident within the light receiving cone angle of the first core 111 can achieve total internal reflection propagation within the first core 111, and the light incident within the light receiving cone angle of the second core 121 can achieve total internal reflection propagation within the second core 121; the light absorbing layer 123 is preferably an optical coating layer or a colored glass layer, that is, the light absorbing layer 123 is made of a film-forming material capable of absorbing visible light, or is made of a colored glass material capable of absorbing visible light. The light absorbing layer 123 can be attached to the outer peripheral surface of the second cladding 122 by deposition or evaporation, or can be made into a glass tube to surround the second cladding 122, so as to absorb the visible light directly incident or incident into its interior after passing through the second core 121 and / or the second cladding 122.

[0039] In some embodiments, such as Figure 1 and Figure 3As shown, the diameter of the first core 111 is more than three times the thickness of the first cladding 112, the diameter of the second core 121 is more than three times the thickness of the second cladding 122, and the thickness of the light-absorbing layer 123 is less than or equal to the thickness of the second cladding 122. Specifically, the first core 111 and the second core 121 are made by a drawing process, and the cross-sectional profiles of both are circular. Their diameters are respectively in the range of 3 μm to 500 μm. Since the first cladding 112 and the second cladding 122 only provide a low-refractive-index interface for the first core 111 and the second core 121, the first cladding 112 and the second cladding 122 only need to have a thickness that meets the requirements of glass tube forming, such as being equal to or greater than 1 μm. At the same time, in order to minimize the size difference between the second light guiding structure 12 and the first light guiding structure 11, the smaller the thickness of the light-absorbing layer 123, the better.

[0040] In some embodiments, such as Figure 1 As shown, the cross-sectional profiles of both the first light guiding structure 11 and the second light guiding structure 12 are circular. That is, the first light guiding structure 11 and the second light guiding structure 12 are respectively cylindrical structures, and voids 100 will be formed after they are stacked on each other. Specifically, the first core 111 and the second core 121 are both cylindrical structures, and the first cladding 112, the second cladding 122, and the light-absorbing layer 123 are all circular tube-shaped structures; the surrounded area of the annular unit 102 includes multiple voids 100, and each void 100 is either unfilled or filled with cladding material. Among them, unfilled means that there is no substance in the void 100 except air, that is, the void 100 is formed as a through hole, and the light emitted by the pixels of the display panel 20 can directly pass through the void 100 to form an image on the surface of the waveguide cover plate 10 facing its light-emitting side; and the cladding material refers to the material used to make the first cladding 112 and / or the second cladding 122. By filling the void 100 with cladding material, the first light guiding structure 11 and the second light guiding structure 12 can be connected more tightly.

[0041] Of course, according to specific situations and requirements, in some other embodiments of the present application, the first cladding 112, the second cladding 122, and the light-absorbing layer 123 can also be structures such as rectangles and hexagons, so that there is a larger contact area between two adjacent first light guiding structures 11, between two adjacent second light guiding structures 12, and between the first light guiding structure 11 and the second light guiding structure 12, which is beneficial to stacking the first light guiding structure 11 and the second light guiding structure 12 more tightly.

[0042] In some embodiments, such as Figure 1 As shown, the outer contour of the light guiding region 101 is rectangular. This is beneficial for the light guiding region 101 to match pixels or sub-pixels with a rectangular outer contour.

[0043] In some embodiments, such asFigure 2 As shown Figure 2 FIG. is a partial top view schematic diagram of a waveguide cover plate provided in some other embodiments of the present application. The outer contour of the light guide region 101 is hexagonal. When the length of the longest side of a pixel or sub-pixel is L and the width of the widest side is W, the length L2 of the longest side of the light guide region 101 ≤ L, and the width W2 of the widest side of the light guide region 101 ≤ W. When the cross-sectional profiles of the first light guide structure 11 and the second light guide structure 12 are both circular, when the first light guide structure 11 and the second light guide structure 12 are stacked and the first light guide structures 11 are stacked with each other, an interspersed arrangement will naturally form without any constraints, that is, the outer peripheral surface of the first light guide structure 11 in one row will abut against the outer peripheral surfaces of two adjacent first light guide structures 11 in the adjacent row, or the outer peripheral surface of the first light guide structure 11 in one row will abut against the outer peripheral surfaces of two adjacent second light guide structures 12 in the adjacent row. In this case, the inner contour of the cross-section of the annular unit 102 will be hexagonal, and at the same time, the outer contour of the light guide region 101 will be hexagonal, which is beneficial to improving the processing efficiency of the waveguide cover plate 10.

[0044] In some embodiments, the cross-sectional area of the first light guide structure 11 is one-twentieth to one-fifth of the area of the pixel of the display panel 20, which is beneficial to ensuring the image transfer effect of the waveguide cover plate 10.

[0045] In some embodiments, the cross-sectional area of the second light guide structure 12 is equal to the cross-sectional area of the first light guide structure 11, which is convenient for processing the waveguide cover plate 10 and is beneficial to improving the processing accuracy of the light guide region 101.

[0046] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present application, and these improvements and refinements are also regarded as the protection scope of the present application.

Claims

1. A waveguide cover plate, characterized in that, It includes a plurality of light guiding regions and a plurality of annular units. Each of the annular units surrounds one of the light guiding regions. The position of the light guiding region can correspond to the position of a pixel or a sub-pixel of the display panel, and the length of the longest side of the light guiding region is less than or equal to the length of the longest side of the pixel or the sub-pixel, and the width of the widest side of the light guiding region is less than or equal to the width of the widest side of the pixel or the sub-pixel. The light guiding region includes a plurality of first light guiding structures, and the annular unit is formed by enclosing a plurality of second light guiding structures. The first light guiding structure and the second light guiding structure can transfer the image on the light incident side of the waveguide cover plate to the light exiting side of the waveguide cover plate, and the second light guiding structure includes a light absorbing layer.

2. The waveguide cover plate according to claim 1, characterized in that, The first light guiding structure includes a first core and a first cladding layer. The refractive index of the first core is greater than that of the first cladding layer, and the first cladding layer surrounds the periphery of the first core; the second light guiding structure further includes a second core and a second cladding layer. The refractive index of the second core is greater than that of the second cladding layer, and the second cladding layer surrounds the periphery of the second core. The light absorbing layer surrounds the periphery of the second cladding layer.

3. The waveguide cover plate according to claim 2, characterized in that, The light absorbing layer is an optical coating layer or a colored glass layer.

4. The waveguide cover plate according to claim 2, characterized in that, The diameter of the first core is more than 3 times the thickness of the first cladding layer, the diameter of the second core is more than 3 times the thickness of the second cladding layer, and the thickness of the light absorbing layer is less than or equal to the thickness of the second cladding layer.

5. The waveguide cover plate according to claim 2, characterized in that, The cross-sectional profile of the first light guiding structure and the cross-sectional profile of the second light guiding structure are both circular.

6. The waveguide cover plate according to claim 5, characterized in that, The surrounding area of the annular unit includes a plurality of voids, and the voids are unfilled or filled with a cladding material.

7. The waveguide cover plate according to claim 5, characterized in that, The outer contour of the light guiding region is rectangular or hexagonal.

8. The waveguide cover plate according to any one of claims 1 to 7, characterized in that, The cross-sectional area of the first light guiding structure is one-twentieth to one-fifth of the area of the pixel; and / or the cross-sectional area of the second light guiding structure is equal to the cross-sectional area of the first light guiding structure.

9. A display device, characterized in that, It includes a display panel and the waveguide cover plate according to any one of claims 1 to 8, and the waveguide cover plate is located on the light exiting side of the display panel.

10. The display device according to claim 9, characterized in that, The waveguide cover plate is adhered to the surface of the display panel facing the light exiting side through an optical adhesive, and the thickness of the optical adhesive is 10 to 200 micrometers.

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