Slanting angle compensation structure, display panel and display device

Abstract

The embodiment of the utility model discloses a squint angle compensation structure, a display panel and a display device. The squint angle compensation structure comprises a substrate; the quarter-wave plate, the reflection type linear polaroid and the absorption type linear polaroid are located on one side of the substrate base plate and stacked in sequence; the compensation layer is located on one side, close to the quarter-wave plate, of the substrate base plate, the in-plane retardation Re of the compensation layer to the light in the wave band of 550 nm meets the condition that Re is smaller than or equal to 3 nm, the vertical retardation Rth meets the condition that Rth is larger than or equal to 50 nm and smaller than or equal to 200 nm, the Re of the lamination of the quarter-wave plate and the compensation layer to the light in the wave band of 550 nm meets the condition that Re is larger than or equal to 135 nm and smaller than or equal to 150 nm, and Rth meets the condition that Rth is larger than or equal to-50 nm and smaller than or equal to 100 nm. The squint angle compensation structure provided by the embodiment of the utility model is provided with the compensation layer, so that light leakage and color cast of the squint angle can be improved, and the display effect is improved.

Description

Technical Field

[0001] The utility model relates to the field of optical technology, and in particular to a slant viewing angle compensation structure, a display panel and a display device. Background Art

[0002] Pure RM and Pure FM is a quarter compensation film made of modified polycarbonate (PC) launched by Teijin Co., Ltd. of Japan. It has the characteristics of reverse wavelength dispersion and can convert in-plane linear polarization into circular polarization. It is widely used in virtual reality (VR), augmented reality (AR), organic light-emitting diode (OLED) display panels, mobile phones, and watch displays. However, due to its material properties, there is high delay interference in the thickness direction, which leads to light leakage at oblique viewing angles, resulting in ghosting, color shift and other defects. Utility Model Content

[0003] The present invention provides a slant viewing angle compensation structure, a display panel, and a display device. The slant viewing angle compensation structure is provided with a compensation layer, which can improve slant viewing angle light leakage and color deviation, thereby improving the display effect.

[0004] According to one aspect of the present invention, a slant viewing angle compensation structure is provided, comprising:

[0005] substrate;

[0006] A quarter wave plate, a reflective linear polarizer, and an absorbing linear polarizer stacked in sequence on one side of the base substrate;

[0007] The compensation layer is located on the side of the base substrate close to the quarter-wave plate, and the in-plane delay Re of the compensation layer for light in the 550nm band satisfies Re≤3nm, and the vertical delay Rth satisfies 50nm≤Rth≤200nm. The stacked layer of the quarter-wave plate and the compensation layer satisfies Re of light in the 550nm band satisfies 135nm≤Re≤150nm, and Rth satisfies -50nm≤Rth≤100nm.

[0008] Optionally, the compensation layer is located on a side of the quarter-wave plate close to the substrate or a side of the quarter-wave plate close to the reflective linear polarizer.

[0009] Optionally, an adhesive is further included, and the two adjacent film layers are bonded together by the adhesive.

[0010] Optionally, the method further includes an anti-reflection layer located on a side of the substrate away from the quarter-wave plate, and the reflectivity of the anti-reflection layer is ≤1%.

[0011] Optionally, the compensation layer includes a liquid crystal curing layer.

[0012] Optionally, the liquid crystal solidified layer is directly solidified on the surface of the adjacent film layer.

[0013] Optionally, the adjacent film layer is the quarter-wave plate, or any one of polyethylene terephthalate (PET), triacetyl cellulose (TAC) or polymethyl methacrylate (PMMA) polymer films.

[0014] Optionally, the substrate includes any one of cycloolefin copolymer COC, polymethyl methacrylate PMMA, polycarbonate PC or inorganic glass.

[0015] According to another aspect of the present invention, a display panel is provided, comprising the above-mentioned oblique viewing angle compensation structure.

[0016] According to another aspect of the present invention, a display device is provided, comprising the above-mentioned display panel.

[0017] The oblique viewing angle compensation structure provided by the embodiment of the present invention includes a substrate; a quarter-wave plate, a reflective linear polarizer, and an absorptive linear polarizer stacked in sequence on one side of the substrate; and a compensation layer located on the side of the substrate near the quarter-wave plate. The compensation layer satisfies the in-plane retardation Re of 550nm light and the vertical retardation Rth of 50nm≤Rth≤200nm for 550nm light. The stack of the quarter-wave plate and the compensation layer satisfies the Re of 135nm≤Re≤150nm and the Rth of -50nm≤Rth≤100nm for 550nm light. By providing the compensation layer, when light is obliquely incident or emitted, the compensation layer generates additional compensation, so that Re=1 / 4λ, and the light is adjusted from elliptically polarized light to circularly polarized light. This can improve oblique viewing angle light leakage and color shift, thereby enhancing the display effect.

[0018] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present invention, nor is it intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 This is a schematic structural diagram of a quarter compensation film in the prior art;

[0021] Figure 2 A schematic structural diagram of a slant viewing angle compensation structure provided by an embodiment of the present utility model;

[0022] Figure 3 A schematic structural diagram of another slant viewing angle compensation structure provided by an embodiment of the present utility model;

[0023] Figure 4 A schematic structural diagram of another slant viewing angle compensation structure provided by an embodiment of the present utility model;

[0024] Figure 5 This is a structural diagram of another slant viewing angle compensation structure provided by an embodiment of the present utility model. DETAILED DESCRIPTION

[0025] In order to help those skilled in the art better understand the present invention, the following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0026] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0027] Figure 1 This is a schematic diagram of the structure of a quarter compensation film in the prior art, refer to Figure 1 The quarter compensation film includes a base substrate 1 and a quarter-wave plate 2, a reflective linear polarizer 3 and an absorptive linear polarizer 4 stacked in sequence on one side of the base substrate 1. The optical path principle is as follows: the display screen light is incident from one side of the quarter-wave plate 2, reflected by the reflective linear polarizer 3, emitted through the quarter-wave plate 2, then reflected by other reflective interfaces, and then emitted into the human eye after passing through the quarter-wave plate 2, the reflective linear polarizer 3 and the absorptive linear polarizer 4, and the display screen is observed.

[0028] External light is incident from one side of the absorptive linear polarizer 4, is emitted through the reflective linear polarizer 3 and the quarter-wave plate 2, is reflected by other reflective interfaces, passes through the quarter-wave plate 2 and the reflective linear polarizer 3 again, and is absorbed by the absorptive linear polarizer 4, thus playing the role of dereflecting light.

[0029] The three-dimensional refractive indices of quarter-wave plate 2 are different: nx1>ny1>nz1. nx1 represents the maximum refractive index within the plane of quarter-wave plate 2, ny1 represents the minimum refractive index within the plane of quarter-wave plate 2, nz1 represents the refractive index along the thickness direction of quarter-wave plate 2, and d represents the material thickness. The in-plane retardation Re = (nx1-ny1) × d. When incident or emitted at a normal viewing angle, Re = (nx1-ny1) × d = 1 / 4λ, and the light is circularly polarized. When incident or emitted at an oblique angle, Re ≠ 1 / 4λ, and the light is elliptically polarized. Circularly polarized light is reflected by the reflective interface and then reverts to linear polarization upon passing through quarter-wave plate 2 again. It can be completely reflected by reflective linear polarizer 3 or completely absorbed by absorptive linear polarizer 4, resulting in no light leakage. Elliptically polarized light is reflected by the reflective interface and then reverts to elliptically polarized light upon passing through quarter-wave plate 2 again. It cannot be completely reflected by the reflective linear polarizer or completely absorbed by the absorptive linear polarizer, resulting in light leakage.

[0030] In order to solve the above problems, an embodiment of the present invention provides an oblique viewing angle compensation structure. By setting a compensation layer, when the light is obliquely incident or emitted, the compensation layer produces additional compensation, so that Re = 1 / 4λ, and the light is adjusted from elliptically polarized light to circularly polarized light, which can improve oblique viewing angle light leakage and color deviation, and enhance the display effect.

[0031] For example, Figure 2 A schematic diagram of a slant viewing angle compensation structure provided by an embodiment of the present invention is provided. Figure 2 The slant viewing angle compensation structure includes: a base substrate 10; a quarter-wave plate 20, a reflective linear polarizer 30, and an absorptive linear polarizer 40 stacked in sequence on one side of the base substrate 10; a compensation layer 50 located on the side of the base substrate 10 close to the quarter-wave plate 20, wherein the in-plane retardation Re of the compensation layer 50 for light in the 550nm band satisfies Re≤3nm, and the vertical retardation Rth satisfies 50nm≤Rth≤200nm, and the stacking of the quarter-wave plate and the compensation layer satisfies 135nm≤Re≤150nm, and Rth satisfies -50nm≤Rth≤100nm.

[0032] Among them, the substrate 10 is used to support other film layers. Optionally, the substrate 10 includes any one of cycloolefin copolymer (COC), polymethyl methacrylate (PMMA), polycarbonate (PC), or inorganic glass, and can be selected according to actual conditions during specific implementation. The quarter-wave plate 20 is also called a "quarter-wave retarder". When light of a certain wavelength is incident perpendicularly and passes through it, the phase difference between the ordinary light and extraordinary light emerging is 1 / 4 wavelength. In the optical path, it is often used to change linearly polarized light into circularly polarized light or elliptically polarized light; or vice versa. Such a wave plate is usually made of a birefringent material cut along the direction parallel to the optical axis into a parallel plane plate, and its thickness should be precisely an odd multiple of the product of the difference between the refractive indices of the two principal axes of the birefringent material and 1 / 4 of the given wavelength. The quarter-wave plate 20 can be prepared by stretching PC material. Both the reflective linear polarizer 30 and the absorptive linear polarizer 40 can transmit linearly polarized light in a specific direction. The difference is that the reflective linear polarizer 30 reflects other polarized light, and the absorptive linear polarizer 40 absorbs light in other polarization directions. The reflective linear polarizer 30 can be prepared by cross-stacking multiple polymers with different refractive indices, such as APF, DBEF, IQPE, IQPS, etc. produced by 3M. The absorptive linear polarizer 40 can be prepared by dyeing polyvinyl alcohol with dichroic particles such as iodine, stretching, and drying.

[0033] The three-dimensional refractive index of the compensation layer 50 satisfies nx2 = ny2 < nz2, where nx2 and ny2 respectively represent the maximum and minimum refractive indices in the plane of the compensation layer 50, that is, there is no difference in the refractive index in the plane, and nz2 represents the refractive index in the thickness direction.

[0034] It can be understood that Figure 2 The compensation layer 50 shown between the substrate 10 and the quarter-wave plate 20 is only schematic. During specific implementation, the position of the compensation layer can be adjusted according to actual conditions. Exemplarily, Figure 3 This is a schematic structural diagram of another oblique-angle compensation structure provided by an embodiment of the present invention. Optionally, the compensation layer 50 is located on the side of the quarter-wave plate 20 close to the substrate 10 ( Figure 2 ) or on the side of the quarter-wave plate 20 close to the reflective linear polarizer 30 ( Figure 3 ).

[0035] When the incident or emerging light is normal, the light is right-circularly polarized light. When the light passes through the compensation layer 50, because nx2 = ny2, there is no additional compensation, so it does not affect the optical effect and there is no light leakage. When the incident or emerging light is oblique, there is an in-plane difference in the refractive index on the plane perpendicular to the oblique incident or emerging direction, that is, the refractive index nx2’ > ny2’. At this time, additional compensation is generated, making Re = 1 / 4λ, and the light is adjusted from elliptically polarized light to right-circularly polarized light. Therefore, the effect changes from light leakage to no light leakage.

[0036] When there is no light leakage, only one display image enters the human eye, so there is no ghosting problem.

[0037] When light leakage occurs, the leaked light also becomes a separate display image, entering the human eye at the same time as the normal display image, causing ghosting. Furthermore, since different wavelengths of light leak into the display at different proportions, color shift can occur. This problem can be improved by correcting it with the above solution.

[0038] Figure 4 A schematic diagram of another oblique viewing angle compensation structure provided by the present invention is provided. Figure 4 Optionally, the oblique viewing angle compensation structure further includes an anti-reflection layer 60 located on a side of the base substrate 10 away from the quarter-wave plate 20 , and the reflectivity of the anti-reflection layer 60 is ≤1%.

[0039] By providing the anti-reflection layer 60 , ghost images can be reduced and light utilization efficiency can be improved.

[0040] Optionally, the compensation layer 50 includes a liquid crystal curing layer.

[0041] Among them, liquid crystal is a good birefringent material. In specific implementation, the liquid crystal can be prepared into a formula liquid, and the formula liquid can be coated on the surface of the substrate, dried, and UV cured to obtain the product.

[0042] Optionally, the liquid crystal solidified layer is directly solidified on the surface of the adjacent film layer.

[0043] In a specific implementation, the adjacent film layer to the liquid crystal curing layer can be a film layer in the slant viewing angle compensation structure, or can be a substrate in the slant viewing angle compensation structure. Optionally, the adjacent film layer is a quarter-wave plate, or any one of polyethylene terephthalate (PET), cellulose triacetate (TAC), or polymethyl methacrylate (PMMA) polymer films.

[0044] Figure 5 A schematic diagram of another oblique viewing angle compensation structure provided by the present invention is provided. Figure 5 Optionally, the slant viewing angle compensation structure further includes an adhesive 70 , and the two adjacent film layers are bonded together by the adhesive 70 .

[0045] Optionally, the adhesive 70 includes any one of epoxy adhesive, vinyl alcohol adhesive, acrylate adhesive, polyurethane adhesive, chloroprene rubber, styrene-butadiene rubber, cyano rubber or silicone rubber.

[0046] It should be noted that Figure 5 The schematic diagram shows the film stacking structure and Figure 2 Same as Figure 3 and Figure 4 The structure may also be provided with an adhesive.

[0047] The present invention also provides a display panel including any of the slant viewing angle compensation structures provided in the above embodiments, wherein the display panel may be a liquid crystal display panel, an organic light emitting display panel, etc., and the specific implementation may be designed according to actual conditions, which is not limited by the present invention.

[0048] The present invention also provides a display device including the display panel provided in the above embodiment. The display device may be a mobile phone, a computer, or a smart wearable device (such as a virtual reality display device VR, an augmented reality display device AR), etc.

[0049] The above specific embodiments do not limit the scope of protection of this utility model. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model shall be included within the scope of protection of this utility model.

Claims

1. A slant viewing angle compensation structure, characterized in that: include: substrate; A quarter wave plate, a reflective linear polarizer, and an absorbing linear polarizer stacked in sequence on one side of the base substrate; The compensation layer is located on the side of the base substrate close to the quarter-wave plate, and the in-plane delay Re of the compensation layer for light in the 550nm band satisfies Re≤3nm, and the vertical delay Rth satisfies 50nm≤Rth≤200nm. The stacked layer of the quarter-wave plate and the compensation layer satisfies Re of light in the 550nm band satisfies 135nm≤Re≤150nm, and Rth satisfies -50nm≤Rth≤100nm.

2. The slant viewing angle compensation structure according to claim 1, wherein: The compensation layer is located on a side of the quarter-wave plate close to the substrate or a side of the quarter-wave plate close to the reflective linear polarizer.

3. The slant viewing angle compensation structure according to claim 2, wherein: It also includes an adhesive, and two adjacent film layers are bonded together by the adhesive.

4. The slant viewing angle compensation structure according to claim 1, wherein: It also includes an anti-reflection layer located on a side of the substrate away from the quarter-wave plate, and the reflectivity of the anti-reflection layer is ≤1%.

5. The slant viewing angle compensation structure according to claim 1, wherein: The compensation layer includes a liquid crystal curing layer.

6. The slant viewing angle compensation structure according to claim 5, characterized in that: The liquid crystal solidified layer is directly solidified on the surface of the adjacent film layer.

7. The slant viewing angle compensation structure according to claim 6, wherein: The adjacent film layer is the quarter-wave plate, or any one of polyethylene terephthalate (PET), triacetyl cellulose (TAC) or polymethyl methacrylate (PMMA) polymer films.

8. The slant viewing angle compensation structure according to claim 1, wherein: The substrate includes any one of cycloolefin copolymer (COC), polymethyl methacrylate (PMMA), polycarbonate (PC) or inorganic glass.

9. A display panel, characterized in that: The invention comprises the slant viewing angle compensation structure described in any one of claims 1 to 8.

10. A display device, characterized in that: The display panel comprises the display panel according to claim 9.

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