Display panel and display device

Abstract

The present disclosure relates to the technical field of display, and particularly relates to a display panel and a display device, which are used for reducing light leakage of the display panel and reducing color deviation. The display panel comprises: a first polarizer, an array substrate, a first liquid crystal layer, a counter substrate and a second polarizer which are sequentially stacked; the optical axis direction of the polarizing layer in the first polarizer is perpendicular to the optical axis direction of the polarizing layer in the second polarizer; one of the first polarizer and the second polarizer further comprises: a compensation layer located on the side of the polarizing layer close to the first liquid crystal layer; the compensation layer comprises a first sub-layer, a second sub-layer and a third sub-layer which are sequentially stacked, and the third sub-layer is the sub-layer closest to the light exit side of the display panel; the optical axis direction of the first sub-layer intersects with the optical axis direction of the polarizing layer in the first polarizer, the optical axis direction of the second sub-layer is perpendicular to the optical axis direction of the polarizing layer in the first polarizer, and the optical axis direction of the third sub-layer intersects with the optical axis direction of the polarizing layer in the second polarizer. The display panel and the display device are used for image display.

Description

Technical Field

[0001] This disclosure relates to the field of display technology, and more particularly to a display panel and display device. Background Technology

[0002] Liquid crystal displays (LCDs) are increasingly widely used due to their advantages such as low power consumption, miniaturization, and thinness. They are used in various fields, including mobile phones, flat panel displays, automotive displays, televisions, and public displays. Utility Model Content

[0003] The purpose of the embodiments of this disclosure is to provide a display panel and a display device for reducing light leakage and color shift of the display panel.

[0004] To achieve the above objectives, the embodiments of this disclosure provide the following technical solutions: Some embodiments of this disclosure provide a display panel, the display panel comprising: a first polarizer, an array substrate, a first liquid crystal layer, an opposing substrate, and a second polarizer stacked sequentially. Both the first polarizer and the second polarizer include a polarizing layer, the optical axis direction of the polarizing layer in the first polarizer being perpendicular to the optical axis direction of the polarizing layer in the second polarizer. One of the first polarizer and the second polarizer further includes a compensation layer. The compensation layer is located on the side of the polarizing layer closest to the first liquid crystal layer. The compensation layer is used to compensate for the phase delay of light transmitted through the compensation layer. The compensation layer includes a first sub-layer, a second sub-layer, and a third sub-layer stacked sequentially, the third sub-layer being the sub-layer closest to the light-emitting side of the display panel. The optical axis direction of the first sub-layer intersects the optical axis direction of the polarizing layer in the first polarizer, the optical axis direction of the second sub-layer is perpendicular to the optical axis direction of the polarizing layer in the first polarizer, and the optical axis direction of the third sub-layer intersects the optical axis direction of the polarizing layer in the second polarizer.

[0005] The display panel provided in the embodiments of this disclosure includes a first polarizer, an array substrate, a first liquid crystal layer, an opposing substrate, and a second polarizer, which are stacked sequentially. Both the first and second polarizers include polarizing layers, and the optical axes of the two polarizing layers are perpendicular. One of the first and second polarizers includes a compensation layer, which can compensate for the phase retardation of light transmitted through it. A third sub-layer in the compensation layer is located closest to the light-emitting side of the display panel. The optical axis of the first sub-layer intersects with the optical axis of the first polarizer, causing the first linearly polarized light emitted from the first polarizer to undergo phase retardation after passing through the first sub-layer, converting it into first elliptically polarized light. When the first elliptically polarized light is incident on a second sub-layer, whose optical axis is perpendicular to that of the first polarizer, the first elliptically polarized light undergoes phase retardation again after passing through the second sub-layer, converting it into second elliptically polarized light. The second elliptically polarized light is incident on the third sub-layer. The optical axis of the third sub-layer intersects with the optical axis of the second polarizing layer. After passing through the third sub-layer, the second elliptically polarized light undergoes phase delay again and is converted into second linearly polarized light. The polarization direction of the second linearly polarized light is perpendicular to the optical axis of the second polarizing layer and cannot pass through the second polarizing layer. As a result, the display panel has almost no light leakage and no color shift under dark and wide viewing angle display, resulting in a better display effect.

[0006] In some embodiments, one of the first sub-layer and the third sub-layer is a first target sub-layer. The first target sub-layer is a +A type compensation layer. The refractive index of the first target sub-layer satisfies: n x >n y =n z Where n x Let n be the refractive index of light in the X direction of the plane containing the first target sublayer. y Let n be the refractive index of light in the Y direction of the plane containing the first target sublayer. z Let Z be the refractive index of light in the thickness direction Z of the first target sublayer.

[0007] In some embodiments, the thickness retardation value of the first target sublayer is λ / 4, and the in-plane retardation value of the first target sublayer is λ / 8. Here, λ is the wavelength of visible light.

[0008] In some embodiments, the first sublayer is the first target sublayer. The second sublayer is a +C type compensation layer, and the refractive index of the second sublayer satisfies: n z >n x =n y The third sublayer is a -C type compensation layer. The refractive index of the third sublayer satisfies: n x =n y >n z .

[0009] In some embodiments, the sum of the thickness delay values ​​of the second sublayer and the third sublayer ranges from -109 nm to -178 nm.

[0010] In some embodiments, the third sublayer is the first target sublayer. The first sublayer is a +C type compensation layer, and the refractive index of the first sublayer satisfies: n z >n x =n y The second sublayer is a -C type compensation layer. The refractive index of the second sublayer satisfies: n x =n y >n z .

[0011] In some embodiments, the sum of the thickness retardation values ​​of the first sublayer and the second sublayer ranges from -94nm to -187nm.

[0012] In some embodiments, one of the first sub-layer and the third sub-layer is a second target sub-layer. The second target sub-layer is a dual-optical-axis compensation layer.

[0013] In some embodiments, the first sublayer is the second target sublayer, and the first sublayer is a -B type compensation layer. The refractive index of the first sublayer satisfies: n x >n y >n z .

[0014] In some embodiments, the in-plane retardation value of the first sublayer ranges from 89 nm to 156 nm. The thickness retardation value of the first sublayer ranges from 53 nm to 129 nm.

[0015] In some embodiments, the second sublayer is a +C type compensation layer. The refractive index of the second sublayer satisfies: n z >n x =n y The third sublayer is a -C type compensation layer. The refractive index of the third sublayer satisfies: n x =n y >n z .

[0016] In some embodiments, the sum of the thickness retardation values ​​of the second sublayer and the third sublayer ranges from -117nm to -194nm.

[0017] In some embodiments, the third sublayer is the second target sublayer, and the third sublayer is a +B type compensation layer. The refractive index of the third sublayer satisfies: n z >n x >n y .

[0018] In some embodiments, the in-plane retardation value of the third sublayer ranges from 32 nm to 98 nm. The thickness retardation value of the third sublayer ranges from -259 nm to -334 nm.

[0019] In some embodiments, the first sublayer is a -C type compensation layer. The refractive index of the first sublayer satisfies: n x =n y >n z The first sublayer is a +C type compensation layer. The refractive index of the second sublayer satisfies: n z >n x =n y .

[0020] In some embodiments, the sum of the thickness retardation values ​​of the first sublayer and the second sublayer ranges from -185nm to -293nm.

[0021] In some embodiments, at least one sublayer of the compensation layer is made of cellulose triacetate.

[0022] In some embodiments, the material of the -C type compensation layer in the compensation layer includes cellulose triacetate.

[0023] In some embodiments, the first sublayer or the second sublayer in the compensation layer is a +C type compensation layer, and the +C type compensation layer includes a cured second liquid crystal film.

[0024] In some embodiments, the other of the first polarizer and the second polarizer further includes a protective layer. The protective layer is located on the side of the polarizer adjacent to the first liquid crystal layer. The material of the protective layer includes cellulose triacetate.

[0025] Some embodiments of this disclosure also provide a display device, including: the display panel described in any of the above embodiments and a backlight module located on the non-light-emitting side of the display panel.

[0026] The beneficial effects that the display device provided in some embodiments of this disclosure can achieve are the same as the beneficial effects that the display panel provided in some embodiments above can achieve, and will not be repeated here. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in this disclosure, the accompanying drawings used in some embodiments of this disclosure will be briefly described below. Obviously, the drawings described below are merely drawings of some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings. Furthermore, the drawings described below can be considered as schematic diagrams and are not intended to limit the actual dimensions, etc., of the products involved in the embodiments of this disclosure.

[0028] Figure 1 This is a structural diagram of a display device according to some embodiments of the present disclosure; Figure 2 This is a structural diagram of another display device according to some embodiments of the present disclosure; Figure 3 This is a structural diagram of a display panel according to one possible implementation; Figure 4A For a Poincaré sphere diagram of light in another possible implementation; Figure 4B According to Figure 4A A magnified structural diagram of a local region DV1 in the image; Figure 5A This is a structural diagram of a display panel according to some embodiments of the present disclosure; Figure 5B This is a structural diagram of another display panel according to some embodiments of the present disclosure; Figure 6 A ray diagram showing the in-plane retardation value of the compensation layer made of positive dispersive material versus the wavelength of the incident light. Figure 7A A Poincaré sphere diagram of light in a display panel according to some embodiments of the present disclosure; Figure 7B According to Figure 7A A magnified structural diagram of a local region DV2 in the image; Figure 8A A Poincaré sphere diagram of light in another display panel according to some embodiments of the present disclosure; Figure 8B According to Figure 8A A magnified structural diagram of a local region DV3 in the image; Figure 9A A Poincaré sphere diagram of light in another display panel according to some embodiments of the present disclosure; Figure 9B According to Figure 9A A magnified structural diagram of a local region of DV4; Figure 10A A Poincaré sphere diagram of light in another display panel according to some embodiments of the present disclosure; Figure 10B According to Figure 10A A magnified structural diagram of a local region DV5 in the image. Detailed Implementation

[0029] The technical solutions in some embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments provided in this disclosure are within the scope of protection of this disclosure.

[0030] Unless the context otherwise requires, throughout the specification and claims, the term "comprising" is interpreted as open-ended and encompassing, meaning "including, but not limited to." In the description of the specification, terms such as "one embodiment," "some embodiments," "exemplary embodiment," "example," or "some examples" are intended to indicate that a particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of this disclosure. The illustrative representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics mentioned may be included in any suitable manner in any one or more embodiments or examples.

[0031] Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this disclosure, unless otherwise stated, "a plurality of" means two or more.

[0032] In describing some embodiments, the term "connection" and its derivative expressions may be used. The term "connection" should be interpreted broadly; for example, "connection" can be a fixed connection, a detachable connection, or an integral part; it can be a direct connection or an indirect connection through an intermediate medium. The embodiments disclosed herein are not necessarily limited to the content of this document.

[0033] "A and / or B" includes the following three combinations: A only, B only, and a combination of A and B.

[0034] In addition, the use of “based on” implies openness and inclusivity, because processes, steps, calculations or other actions “based on” one or more of the stated conditions or values ​​may in practice be based on additional conditions or values ​​beyond those stated.

[0035] As used herein, “about,” “approximately,” or “approximately” includes the stated value and the average value within an acceptable range of deviation from the given value, wherein the acceptable range of deviation is determined by a person skilled in the art taking into account the measurement under discussion and the error associated with the measurement of the given quantity (i.e., the limitations of the measurement system).

[0036] As used herein, "perpendicular" and "equal" include the described situation and situations that are similar to the described situation, within an acceptable deviation range, which is determined by those skilled in the art taking into account the measurement under discussion and the error associated with the measurement of a particular quantity (i.e., the limitations of the measurement system). For example, "perpendicular" includes absolute perpendicularity and approximate perpendicularity, where the acceptable deviation range for approximate perpendicularity could be, for example, a deviation within 5°. "Equal" includes absolute equality and approximate equality, where the acceptable deviation range for approximate equality could be, for example, a difference between the two equalities less than or equal to 5% of either one.

[0037] It should be understood that when a layer or element is referred to as being on another layer or substrate, it can mean that the layer or element is directly on the other layer or substrate, or that there is an intermediate layer between the layer or element and the other layer or substrate.

[0038] This document describes exemplary embodiments with reference to cross-sectional views and / or plan views, which are idealized exemplary drawings. In the drawings, the thickness of layers and the area of ​​regions are enlarged for clarity. Therefore, variations in shape relative to the drawings are contemplated due to, for example, manufacturing techniques and / or tolerances. Thus, exemplary embodiments should not be construed as being limited to the shapes of the regions shown herein, but rather include shape deviations due to, for example, manufacturing processes. For example, etched areas shown as rectangular would typically have curved features. Therefore, the regions shown in the drawings are schematic in nature, and their shapes are not intended to show the actual shapes of the areas of the device, nor are they intended to limit the scope of the exemplary embodiments.

[0039] like Figure 1As shown, some embodiments of this disclosure provide a display device 1. This display device 1 can be any display device that displays either moving (e.g., video) or stationary (e.g., still images), and whether it is text or an image. More specifically, the display device of the described embodiments is contemplated for implementation in or associated with a variety of electronic devices, such as (but not limited to) mobile phones, wireless devices, personal data assistants (PDAs), handheld or portable computers, GPS receivers / navigators, cameras, MP4 video players, camcorders, game consoles, watches, clocks, calculators, television monitors, flat panel displays, computer monitors, automotive displays (e.g., odometer displays, etc.), navigators, cockpit controllers and / or displays, displays of camera views (e.g., displays of rearview cameras in vehicles), electronic photographs, electronic billboards or signs, projectors, architectural structures, packaging and aesthetic structures (e.g., displays of images of a piece of jewelry), etc.

[0040] For example, the above-mentioned display device 1 includes: a frame, a display driver IC (Integrated Circuit), and other electronic components.

[0041] In some embodiments, such as Figure 1 As shown, the above-mentioned display device 1 also includes a display panel 3.

[0042] In some examples, the display panel 3 described above can be an LCD display panel.

[0043] For example, the driving method of the display panel 3 can be an active matrix driving method, and the display panel 3 can be, for example, a thin film transistor liquid crystal display (TFT-LCD).

[0044] In the embodiments of this disclosure, the display panel 3 can be an ADS (Advanced Super Dimension Switch) display type.

[0045] For example, such as Figure 2 As shown, the display panel 3 may include an array substrate 31, a first liquid crystal layer 32, and an opposing substrate 33 stacked sequentially. The opposing substrate 33 and the array substrate 31 are disposed opposite to each other, and the first liquid crystal layer 32 is located between the array substrate 31 and the opposing substrate 33.

[0046] For example, such as Figure 2As shown, the array substrate 31 may include: a first substrate 301, and a pixel circuit layer 302, a pixel electrode layer 303, and a common electrode layer 304 located on one side of the first substrate 301. The pixel circuit layer 302 includes a plurality of pixel driving circuits, each including at least one transistor TFT. The pixel electrode layer 303 includes a plurality of pixel electrodes spaced apart. The plurality of pixel electrodes are electrically connected to the plurality of pixel driving circuits, and the pixel driving circuits provide pixel voltages to the corresponding pixel electrodes. The common electrode layer 304 includes a common electrode.

[0047] For example, such as Figure 2 As shown, the opposing substrate 33 may include a second substrate 305 and a color filter layer 306 located on the second substrate 305.

[0048] For example, the first liquid crystal layer 32 includes a plurality of liquid crystal molecules. In the pixel electrode layer 303, the pixel electrode and the common electrode cooperate with each other to form an electric field, under the drive of the electric field, the liquid crystal molecules can be deflected.

[0049] The color filter layer 306 includes various color filters 3061. For example, when the light incident on the color filters is white light, the color filters 3061 may include a red filter, a green filter, and a blue filter. The red filter allows only red light in the incident light to pass through, the green filter allows only green light in the incident light to pass through, and the blue filter allows only blue light in the incident light to pass through.

[0050] The opposing substrate 33 also includes a black matrix 307. The black matrix 307 is located between two adjacent color filters 3061 and can be used to prevent light mixing.

[0051] like Figure 2 As shown, the display panel 3 also includes: a first polarizer 34 located on the side of the array substrate 31 away from the first liquid crystal layer 32, and a second polarizer 35 located on the side of the opposing substrate 33 away from the first liquid crystal layer 32.

[0052] like Figure 2 As shown, the display device 1 further includes a backlight module 2. The backlight module 2 is located on the non-light-emitting side of the display panel 3. The backlight module 2 provides backlight to the display panel 3.

[0053] For example, the backlight module 2 can be a direct-lit backlight module or a side-lit backlight module.

[0054] Understandably, the backlight provided by the backlight module 2 can pass through the array substrate 31 and be incident on the liquid crystal molecules in the liquid crystal layer 32. Under the influence of the electric field formed by the pixel electrodes and the common electrode, the liquid crystal molecules undergo a certain degree of flipping, thereby changing the polarization direction of the light passing through the liquid crystal molecules. The light then passes through the color filters of different colors in the opposing substrate 33 and exits. The exited light includes various colors of light, such as red light, green light, and blue light. The various colors of light work together to enable the display panel 3 and the display device 1 to achieve color display.

[0055] Among them, such as Figure 3 and Figure 5A As shown, both the first polarizer 34 and the second polarizer 35 include a polarizing layer, and the optical axes of the two polarizing layers are perpendicular to each other.

[0056] For example, the polarizing layer in the first polarizer 34 can be the first polarizing layer 361, and the polarizing layer in the second polarizer 35 can be the second polarizing layer 362.

[0057] Understandably, in dark display conditions, the backlight light provided by the backlight module 2 at a positive viewing angle forms 0° linearly polarized light after passing through the first polarizing layer 361. Then, it passes through the liquid crystal molecules of the first liquid crystal layer 32 (which do not deflect) and is incident on the second polarizing layer 362. At a positive viewing angle, the optical axis of the second polarizing layer 362 is perpendicular to the optical axis of the first polarizing layer 361. The second polarizing layer 362 can only pass through 90° linearly polarized light. Therefore, the aforementioned 0° linearly polarized light cannot pass through the second polarizing layer 362, resulting in no light leakage in dark display conditions at a positive viewing angle.

[0058] For example, the optical axis of the first polarizing layer 361 lies in the plane containing the first polarizing layer 361. The optical axis of the second polarizing layer 362 lies in the plane containing the second polarizing layer 362. The aforementioned 0° linearly polarized light refers to light whose electric field vibration direction lies in the plane containing the first polarizing layer, and the angle between the electric field vibration direction and the optical axis of the first polarizing layer is 0°. 90° linearly polarized light refers to light whose electric field vibration direction lies in the plane containing the first polarizing layer, and the angle between the electric field vibration direction and the optical axis of the first polarizing layer is 90°.

[0059] In dark display conditions, the oblique or wide-viewing-angle backlight provided by the backlight module 2 forms non-0° linearly polarized light after passing through the first polarizing layer 361. Then, it passes through the liquid crystal molecules of the first liquid crystal layer 32 (which do not deflect) and is incident on the second polarizing layer 362. At wide viewing angles, the optical axis of the second polarizing layer 362 is not perpendicular to the optical axis of the first polarizing layer 361. Therefore, the non-0° linearly polarized light is not perpendicular to the optical axis of the second polarizing layer 362. A portion of this linearly polarized light can pass through the second polarizing layer 362, resulting in light leakage in dark display conditions at wide viewing angles.

[0060] Based on this, in one possible implementation, such as Figure 3 As shown, a first compensation layer 371' and a second compensation layer 372' are disposed in the second polarizer 35 of the display panel 3'. The second compensation layer 372' is located between the second polarizer 362 and the first compensation layer 371'. The first compensation layer 371' can be a -C type compensation layer, and the second compensation layer 372' can be a +B type compensation layer. The first compensation layer 371' and the second compensation layer 372' are used to compensate for the phase delay of light to avoid light leakage and reduce color shift. For example, no protective layer is disposed between the second compensation layer 372' and the first liquid crystal layer 32, but a protective layer 382 is disposed between the first polarizer 361 and the first liquid crystal layer 32.

[0061] Specifically, in dark display conditions, the oblique or wide-viewing-angle backlight provided by the backlight module 2, after passing through the first polarizing layer 361, forms non-0° first linearly polarized light. This light then passes through the liquid crystal molecules of the first liquid crystal layer 32 and is incident on the first compensation layer 371' in the second polarizer 35. Under the compensation effect of the first compensation layer 371', the first linearly polarized light is converted into first elliptically polarized light and incident on the second compensation layer 372'. Under the compensation effect of the second compensation layer 372', the first elliptically polarized light is approximately converted into non-90° second linearly polarized light or second elliptically polarized light. This second linearly polarized light or second elliptically polarized light is incident on the second polarizing layer 362. At wide viewing angles, the polarization direction of this second linearly polarized light or second elliptically polarized light is approximately perpendicular or perpendicular to the optical axis of the second polarizing layer, resulting in almost no light leakage and low color shift in dark display conditions at wide viewing angles. It should be noted that... Figure 3 The opposing substrate 33 disposed between the first compensation layer 371' and the first liquid crystal layer 32 is not shown in the figure, nor is the array substrate 31 disposed between the protective layer 382 and the first liquid crystal layer 32. It can be understood that the positions of the opposing substrate and the array substrate can be interchanged. That is, the array substrate can also be disposed between the first compensation layer 371' and the first liquid crystal layer 32, and the opposing substrate 33 can also be disposed between the protective layer 382 and the first liquid crystal layer 32.

[0062] For example, the protective layer 382 can be made of cellulose triacetate (TAC), the +B type compensation layer is generally made of acrylic (Poly methyl methacrylate, PMMA), and the -C type compensation layer is generally made of COP (Cyclic olefin polymer). Both acrylic and COP materials are easily affected by raw material supply limitations and have high costs, which is detrimental to reducing the manufacturing cost of the display panel 3.

[0063] Based on this, the above-mentioned -C type compensation layer can be prepared using cellulose triacetate, and the +B type compensation layer can be prepared using COP or acrylic materials, thereby alleviating the problem of raw material supply shortage and reducing the manufacturing cost of display panel 3.

[0064] In another possible implementation, the first compensation layer 371' is set as a +A type compensation layer, and the second compensation layer 372' is set as a +C type compensation layer. A Poincaré sphere is created for the light in the display panel in this implementation, see [link to documentation]. Figure 4A and Figure 4B .

[0065] refer to Figure 4A and Figure 4B In the Poincaré sphere diagram, spheres with different fillings represent different colors of light, where G represents green light, R represents red light, and B represents blue light. Furthermore, in... Figure 4A and Figure 4BIn the diagram, positions 1, 2, 3, and 4 represent the polarization states of the three colors of light with wide viewing angles after passing through different film layers. Position 1 represents the polarization state of the light emitted after the backlight passes through the first polarizing layer 361, and position 2 represents the polarization state of the light after passing through the first liquid crystal layer 32. It can be seen that the polarization state of the light does not change much after passing through the first liquid crystal layer 32; this light is approximately located near the equatorial EQT of the Poincaré sphere, and is roughly linearly polarized. Position 3 represents the polarization state of the light after passing through the first compensation layer 371'; this light is relatively far from the equatorial EQT and is located below it. After compensation by the first compensation layer 371', the aforementioned linearly polarized light forms elliptically polarized light located below the equatorial EQT. Position 4 is the polarization state position of the light after passing through the second compensation layer 372'. The position of this light is relatively close to the equatorial EQT position, but does not reach the equatorial EQT position. This light is another type of elliptically polarized light located below the equatorial EQT. After this elliptically polarized light is incident on the second polarization layer 362, some light still comes out. There is light leakage in the dark state at a large viewing angle, and the displayed picture has color shift. The display effect needs to be further improved.

[0066] The materials of the first compensation layer 371' and the second compensation layer 372' mentioned above include positive dispersion materials.

[0067] The in-plane retardation value R of the compensation layer made of positive dispersive material o The relationship with the wavelength λ of the incident light can be found by referring to... Figure 6 As the incident light wavelength λ increases, the in-plane retardation value R of the compensation layer increases. o The in-plane delay value of the compensation layer is continuously reduced. The in-plane delay value of the compensation layer is wavelength-dependent. The same compensation layer has different in-plane delay values ​​for different wavelengths of light, resulting in different phase changes for different wavelengths of light, and thus different compensation effects for different wavelengths of light.

[0068] Based on this, refer to Figure 5A and Figure 5B In some embodiments of this disclosure, one of the first polarizer 34 and the second polarizer 35 further includes a compensation layer 37. The compensation layer 37 is located on the side of the polarizer layer closest to the first liquid crystal layer 32.

[0069] Understandable, Figure 5A and Figure 5B The array substrate and the opposing substrate are not shown in the diagram. Their positions can be found by referring to [reference needed]. Figure 2 . Figure 2 The positions of the opposing substrate 33 and the array substrate 31 can be interchanged. That is, the opposing substrate can be disposed between the first polarizer 34 and the first liquid crystal layer 32, while the array substrate is disposed between the second polarizer 35 and the first liquid crystal layer 32.

[0070] For example, when no power is applied, the optical axis direction of the liquid crystal molecules in the first liquid crystal layer 32 is the same as or parallel to the optical axis direction of the polarizing layer in the first polarizer 34. The liquid crystal molecules in the first liquid crystal layer 32 do not participate in phase compensation.

[0071] The compensation layer 37 is used to compensate for the phase delay of the light transmitted through the compensation layer 37. For example, under the compensation effect of the compensation layer 37, the incident linearly polarized light will produce a certain amount of phase delay, and will then be converted into another type of linearly polarized light, or into elliptically polarized light, etc., so that the deflection state of the outgoing light is different from that of the incident light.

[0072] like Figure 5A As shown, the compensation layer 37 includes a first sub-layer 371, a second sub-layer 372 and a third sub-layer 373 stacked in sequence, with the third sub-layer 373 being the sub-layer closest to the light-emitting side of the display panel 3.

[0073] The light-emitting side of display panel 3 is the side on which the display screen is displayed.

[0074] For example, such as Figure 5B As shown, the first polarizer 34 includes a compensation layer 37, a third sub-layer 373 located between the first liquid crystal layer 32 and the second sub-layer 372, and a first sub-layer 371 located between the first polarizing layer 361 and the second sub-layer 372.

[0075] For example, such as Figure 5A As shown, the second polarizer 35 includes the aforementioned compensation layer 37, the third sub-layer 373 is located between the second sub-layer 372 and the second polarizer 362, and the first sub-layer 371 is located between the first liquid crystal layer 32 and the second sub-layer 372.

[0076] For example, the optical axis direction of the first sub-layer 371 intersects with the optical axis direction of the polarizing layer in the first polarizer 34, the optical axis direction of the second sub-layer 372 is perpendicular to the optical axis direction of the polarizing layer in the first polarizer 34, and the optical axis direction of the third sub-layer 373 intersects with the optical axis direction of the polarizing layer in the second polarizer 35.

[0077] For example, the optical axis of the first polarizing layer 361 lies in the plane containing the first polarizing layer 361. The optical axis of the second polarizing layer 362 lies in the plane containing the second polarizing layer 362. The angle between the optical axis of the first sub-layer 371 and the optical axis of the first polarizing layer 361 is greater than 0° and less than or equal to 90°.

[0078] For example, the angle between the optical axis of the third sub-layer 373 and the optical axis of the second polarizing layer 362 is greater than 0° and less than or equal to 90°. The angle between the optical axis of the second sub-layer 372 and the optical axis of the polarizing layer in the first polarizer 34 is 90°.

[0079] Therefore, the backlight light with a wide viewing angle, after passing through the first polarizing layer 361, forms first linearly polarized light. Since the optical axis of the first polarizing layer 361 intersects with the optical axis of the first sub-layer 371, the first linearly polarized light is converted into first elliptically polarized light (or another type of linearly polarized light) under the compensation effect of the first sub-layer 371. Then, the first elliptically polarized light is incident on the second sub-layer 372, and under the compensation effect of the second sub-layer 372, it is converted into second elliptically polarized light and then incident on the third sub-layer 373. Under the compensation effect of the third sub-layer 373, it is converted into second linearly polarized light. The polarization direction of the second linearly polarized light is perpendicular to the optical axis of the second polarizing layer 362, so that the second linearly polarized light cannot pass through the second polarizing layer 362 and thus avoids light leakage and reduces the degree of color shift.

[0080] The polarization direction of the first linearly polarized light is different from that of the second linearly polarized light, and the polarization direction of the first elliptically polarized light is different from that of the second elliptically polarized light.

[0081] The display panel 3 provided in the embodiments of this disclosure includes a first polarizer 34, an array substrate 31, a first liquid crystal layer 32, an opposing substrate 33, and a second polarizer 35 stacked sequentially. Both the first polarizer 34 and the second polarizer 35 include polarizing layers, and the optical axes of the two polarizing layers are perpendicular. One of the first polarizer 34 and the second polarizer 35 includes a compensation layer 37, thereby compensating for the phase delay of light transmitted through the compensation layer. Furthermore, the third sub-layer 373 in the compensation layer is the sub-layer closest to the light-emitting side of the display panel 3. The optical axis of the first sub-layer 371 intersects with the optical axis of the first polarizer 361, causing the first linearly polarized light emitted from the first polarizer 361 to undergo phase delay or phase change after passing through the first sub-layer 371, converting it into first elliptically polarized light. First elliptically polarized light is incident on the second sub-layer 372, whose optical axis is perpendicular to that of the first polarizing layer 361. After passing through the second sub-layer 372, the first elliptically polarized light undergoes a phase delay or phase change, converting into second elliptically polarized light. Second elliptically polarized light is incident on the third sub-layer 373, whose optical axis intersects with that of the second polarizing layer 362. After passing through the third sub-layer 373, the second elliptically polarized light undergoes a phase delay or phase change, converting into second linearly polarized light. The polarization direction of this second linearly polarized light is perpendicular to the optical axis of the second polarizing layer 362, preventing it from passing through the second polarizing layer 362. This results in almost no light leakage and no color shift in the display panel under dark, wide-viewing-angle conditions, leading to a better display effect.

[0082] For ease of explanation, the following embodiment will be described using the example of a second polarizer 35 including a compensation layer 37 located between a second polarizer 362 and a first liquid crystal layer 32.

[0083] In some examples, such as Figure 5A As shown, both the first polarizer 34 and the second polarizer 35 include a substrate layer 381.

[0084] For example, the substrate 381 is located on the side of the polarizing layer away from the first liquid crystal layer 32.

[0085] For example, the material of the base layer 381 can be polyethylene terephthalate (PET), etc.

[0086] The base layer 381 can protect and support the polarizing layer.

[0087] For example, the other of the first polarizer 34 and the second polarizer 35 also includes a protective layer 382.

[0088] For example, the first polarizer 34 also includes a protective layer 382.

[0089] The protective layer 382 is located on the side of the polarizing layer closest to the first liquid crystal layer 32. The material of the protective layer 382 includes cellulose triacetate.

[0090] For example, the protective layer 382 is located on the side of the first polarizing layer 361 away from the base layer 381, and is used to protect the first polarizing layer 361 from physical damage or chemical corrosion.

[0091] In some examples, at least one sublayer of the aforementioned compensation layer 37 is made of cellulose triacetate.

[0092] For example, the material of the first sublayer 371 is cellulose triacetate, and / or the material of the second sublayer 372 is cellulose triacetate, and / or the material of the third sublayer 373 is cellulose triacetate.

[0093] Therefore, the material of the compensation layer 37 can include cellulose triacetate, reducing the use of acrylic and / or COP materials, thereby alleviating the problem of raw material supply shortage and reducing the manufacturing cost of the display panel 3. Optionally, the film layer containing the cellulose triacetate material can be stretched laterally or longitudinally to form the compensation layer, while the cellulose triacetate material contained in the protective layer 382 may not be stretched laterally or longitudinally.

[0094] As described above, the first polarizer 34 includes a protective layer 382, ​​while the second polarizer 35 does not. This allows for a smaller thickness in the second polarizer 35, facilitating a thinner and lighter design for the display panel 3. Furthermore, at least one sublayer in the compensation layer of the second polarizer 35 is made of the same material as the protective layer 382, ​​thus allowing this sublayer to also protect the second polarizing layer 362.

[0095] The structure of the compensation layer 37 can be varied and can be configured according to actual needs. The embodiments disclosed herein do not impose any limitations on this.

[0096] For example, the compensation layer provided in this disclosure includes a positive dispersion material. The preparation method of the compensation layer using a positive dispersion material is relatively simple and easy, which helps to reduce the difficulty of preparing the compensation layer and the display panel.

[0097] In some embodiments, one of the first sublayer 371 and the third sublayer 373 is the first target sublayer.

[0098] For example, the first target sublayer is a single optical axis compensation layer.

[0099] For example, the first sublayer 371 is the first target sublayer. Similarly, the third sublayer 373 is the first target sublayer.

[0100] For example, the first target sublayer is a +A type compensation layer. The refractive index of the first target sublayer satisfies: n x >n y =n z Where n x Let n be the refractive index of light in the X direction along the plane of the first target sublayer. y Let n be the refractive index of light in the Y direction of the plane containing the first target sublayer. z Let Z be the refractive index of light in the thickness direction Z of the first target sublayer.

[0101] For example, the X direction of the plane containing the first target sublayer is the optical axis direction of the first target sublayer.

[0102] The first target sublayer can cause phase delay or phase change of the light incident on it, thereby changing the polarization state of the light and thus helping to reduce light leakage and color shift of the display panel.

[0103] For example, the in-plane delay value R of the first target sub-layer o The thickness delay value R of the first target sublayer is λ / 4. th It is λ / 8. Where λ is the wavelength of visible light.

[0104] The phase difference δ between the incident light rays and the light rays exiting the first target sublayer satisfies: δ = (2π / λ) (n e -n o )d.

[0105] Where, n e n is the refractive index of unusual light in the first target sublayer. oLet be the refractive index of ordinary light in the first target sublayer, and d be the thickness of the first target sublayer. (n) e -n o d is the in-plane delay value.

[0106] Using the aforementioned formula for calculating the phase difference δ and the in-plane delay value R of the first target sublayer... o The phase difference δ can be calculated to be 2π / 4, or 90°. This ensures that the polarization direction of at least a portion of the light incident on the first target sub-layer is approximately 90° from the polarization direction of the light emanating from the first target sub-layer. Combined with the compensation effects of the second sub-layer 372 and the third sub-layer 373, this helps reduce light leakage and color shift at wide viewing angles in the light emanating from the compensation layer 37.

[0107] For example, the wavelength range of visible light here can be 380nm to 750nm. Therefore, the in-plane retardation value of the first target sublayer ranges from 95nm to 187.5nm, and the thickness retardation value of the first target sublayer ranges from 47.5nm to 93.75nm.

[0108] For example, the wavelength range of red light can be 620nm~750nm, the wavelength range of green light can be 490nm~580nm, and the wavelength range of blue light can be 440nm~485nm.

[0109] For example, the wavelength of red light can be 660 nm, the wavelength of green light can be 535 nm, and the wavelength of blue light can be 440 nm. Therefore, the in-plane retardation value of the first target sublayer ranges from 100 nm to 170 nm, and the thickness retardation value of the first target sublayer ranges from 50 nm to 85 nm.

[0110] In some examples, the first sub-layer 371 mentioned above is the first target sub-layer.

[0111] For example, the optical axis direction of the second sublayer 372 is opposite to that of the third sublayer 373.

[0112] The second sublayer 372 is a +C type compensation layer, and the refractive index of the second sublayer 372 satisfies: n z >n x =n y .

[0113] The second sub-layer 372 is a single optical axis compensation layer. The Z direction of the plane where the second sub-layer 372 is located is the optical axis direction of the second sub-layer 372, for example, the out-of-plane direction of the second sub-layer 372.

[0114] The third sublayer 373 is a -C type compensation layer. The refractive index of the third sublayer 373 satisfies: n x =n y >n z.

[0115] The third sublayer 373 is a single optical axis compensation layer. The Z direction of the plane where the third sublayer 373 is located is the optical axis direction of the third sublayer 373. For example, in the in-plane direction of the second sublayer 372, the optical axis direction of the third sublayer 373 is opposite to the optical axis direction of the second sublayer 372.

[0116] Therefore, the first linearly polarized light emitted from the first polarizing layer 361, after passing through the +A type compensation layer (i.e., the first sub-layer 371), is approximately converted into first elliptically polarized light. Then, it passes through the +C type compensation layer (i.e., the second sub-layer 372). The optical axis directions of the +C type compensation layer and the +A type compensation layer are different, so the +C type compensation layer compensates for the first elliptically polarized light, changing the polarization direction of the first elliptically polarized light, for example, converting it into second elliptically polarized light. Then, it passes through the -C type compensation layer (i.e., the third sub-layer 373). The optical axis direction of the third sub-layer 373 is opposite to that of the second sub-layer 372, causing the second elliptically polarized light to be converted into second linearly polarized light. For example, the polarization direction of the second linearly polarized light is perpendicular or approximately perpendicular to the optical axis direction of the second polarizing layer 362. The second linearly polarized light can hardly pass through the second polarizing layer 362 and is emitted, thereby reducing the amount of light leakage of the display panel 3 in dark display and reducing the degree of color shift of the display panel 3 at large viewing angles.

[0117] In some examples, the sum of the thickness retardation values ​​of the second sublayer 372 and the third sublayer 373 ranges from -109 nm to -178 nm.

[0118] For example, the sum of the thickness retardation values ​​of the second sublayer 372 and the third sublayer 373 ranges from -109nm to -169nm, -122nm to -172nm, -118nm to -178nm, -109nm to -172nm, -122nm to -172nm, or -169nm to -178nm.

[0119] For example, the sum of the thickness retardation values ​​of the second sublayer 372 and the third sublayer 373 can be -109nm, -118nm, -122nm, -169nm, -172nm, or -178nm.

[0120] The above configuration ensures that the first elliptically polarized light passing through the first sub-layer 371 is approximately converted into second linearly polarized light under the compensation effect of the second sub-layer 372 and the third sub-layer 373. As a result, the second linearly polarized light can hardly pass through the second polarizing layer 362 and is emitted, thereby reducing the amount of light leakage of the display panel 3 in dark display and reducing the degree of color shift of the display panel 3 at wide viewing angles.

[0121] To create a Poincaré sphere from the light rays in the display panel in this example, see... Figure 7Aand Figure 7B .

[0122] refer to Figure 7A and Figure 7B In the Poincaré sphere diagram, position 1 represents the polarization state of the light emitted after the backlight passes through the first polarizing layer 361. Position 2 represents the polarization state of the light after passing through the first liquid crystal layer 32. The polarization state of the light does not change significantly after passing through the first liquid crystal layer 32; this light is approximately located near the equatorial EQT position of the Poincaré sphere, and is roughly linearly polarized. Position 3 represents the polarization state of the aforementioned linearly polarized light after passing through the first sublayer 371; this light is located far from the equatorial EQT position. It can be seen that after the compensation effect of the first sublayer 371, the linearly polarized light is converted into elliptically polarized light located below the equatorial EQT. Position 4 represents the polarization state of the aforementioned elliptically polarized light after passing through the second sublayer 372; this light is also far from the equatorial EQT position. It can be seen that after the compensation effect of the second sublayer 372, the elliptically polarized light is converted into elliptically polarized light located above the equatorial EQT. Position 5 represents the polarization state of the second elliptically polarized light after passing through the third sublayer 373, and this light ray is located near the equatorial EQT position. It can be seen that after compensation by the third sublayer 373, the second elliptically polarized light is converted into second linearly polarized light located near the equatorial EQT. After this second linearly polarized light is incident on the second polarizing layer 362, less light is emitted, less light leakage occurs, and the degree of color shift is lower.

[0123] In other examples, the third sublayer 373 is the first target sublayer. For example, the optical axis direction of the second sublayer 372 is opposite to that of the first sublayer 371.

[0124] The first sublayer 371 is a +C type compensation layer, and the refractive index of the first sublayer 371 satisfies: n z >n x =n y .

[0125] The second sublayer 372 is a -C type compensation layer. The refractive index of the second sublayer 372 satisfies: n x =n y >n z .

[0126] Therefore, the first linearly polarized light emitted from the first polarizing layer 361, after passing through the +C type compensation layer (i.e., the first sub-layer 371), is roughly converted into first elliptically polarized light. Then, it passes through the -C type compensation layer (i.e., the second sub-layer 372). Since the optical axis directions of the -C type compensation layer and the +C type compensation layer are different, the -C type compensation layer compensates for the first elliptically polarized light, forming second elliptically polarized light. Then, it passes through the third sub-layer 373, which is a +A type compensation layer. The optical axis direction of the +A type compensation layer intersects with the optical axis direction of the -C type compensation layer, causing the second elliptically polarized light to be converted into second linearly polarized light. For example, the polarization direction of the second linearly polarized light is perpendicular or roughly perpendicular to the optical axis direction of the second polarizing layer 362. The third linearly polarized light can hardly pass through the second polarizing layer 362 and is emitted, thereby reducing the amount of light leakage of the display panel 3 in dark display and reducing the degree of color shift of the display panel 3 at large viewing angles.

[0127] In some examples, the sum of the thickness retardation values ​​of the first sublayer 371 and the second sublayer 372 ranges from -94nm to -187nm.

[0128] For example, the sum of the thickness retardation values ​​of the first sublayer 371 and the thickness retardation values ​​of the second sublayer 372 can be in the range of -94nm to -154nm, -124nm to -184nm, -127nm to -187nm, -94nm to -184nm, -124nm to -187nm, -154nm to -187nm, or -127nm to -184nm.

[0129] For example, the sum of the thickness retardation value of the first sublayer 371 and the thickness retardation value of the second sublayer 372 can be -94nm, -124nm, -127nm, -154nm, -184nm, or -187nm.

[0130] To create a Poincaré sphere from the light rays in the display panel in this example, see... Figure 8A and Figure 8B .

[0131] refer to Figure 8A and Figure 8BIn the Poincaré sphere diagram, position 1 represents the polarization state of the light emitted after the backlight passes through the first polarizing layer 361. Position 2 represents the polarization state of the light after passing through the first liquid crystal layer 32. The polarization state of the light does not change significantly after passing through the first liquid crystal layer 32; this light is approximately located near the equatorial EQT position of the Poincaré sphere, and is roughly the first linearly polarized light. Position 3 represents the polarization state of the aforementioned first linearly polarized light after passing through the first sublayer 371; this light is relatively far from the equatorial EQT position. It can be seen that after the compensation effect of the first sublayer 371, the first linearly polarized light is converted into first elliptically polarized light located above the equatorial EQT. Position 4 represents the polarization state of the first elliptically polarized light after passing through the second sublayer 372; this light is relatively close to the equatorial EQT position. It can be seen that after the compensation effect of the second sublayer 372, the first elliptically polarized light is converted into second elliptically polarized light located above the equatorial EQT. Position 5 represents the polarization state of the second elliptically polarized light after passing through the third sublayer 373, and this light ray is located near the equatorial EQT position. It can be seen that after compensation by the third sublayer 373, the second elliptically polarized light is converted into second linearly polarized light located near the equatorial EQT. After this second linearly polarized light is incident on the second polarizing layer 362, less light is emitted, less light leakage occurs, and the degree of color shift is lower.

[0132] In other embodiments, one of the first sublayer 371 and the third sublayer 373 is a second target sublayer. The second target sublayer is a dual-optical-axis compensation layer.

[0133] The second target sublayer has two optical axes.

[0134] Therefore, the light emitted from the first polarizing layer 361 can be compensated by the second target sub-layer when it is incident on the second target sub-layer, which helps to reduce the color shift and light leakage of the light emitted from the second polarizing layer 362.

[0135] In some examples, the first sublayer 371 is the second target sublayer, and the first sublayer 371 is a -B type compensation layer 37. The refractive index of the first sublayer 371 satisfies: n x >n y >n z .

[0136] Therefore, the first sub-layer 371 can cause the light incident on it to undergo phase delay, thereby changing the polarization state of the light and thus helping to reduce light leakage and color shift of the display panel.

[0137] In some examples, the in-plane retardation value of the first sublayer 371 ranges from 89 nm to 156 nm. The thickness retardation value of the first sublayer 371 ranges from 53 nm to 129 nm.

[0138] For example, the in-plane delay value range of the first sublayer 371 can be 89nm~149nm, 91nm~151nm, 96nm~156nm, 89nm~151nm, 91nm~156nm or 101nm~156nm.

[0139] For example, the in-plane delay value of the first sublayer 371 can be 89nm, 91nm, 96nm, 101nm, 149nm, 151nm or 156nm.

[0140] For example, the thickness retardation value of the first sublayer 371 can be in the range of 53nm~123nm, 55nm~125nm, 59nm~129nm, 53nm~125nm, 55nm~89nm or 89nm~129nm.

[0141] For example, the thickness delay value of the first sublayer 371 can be 53nm, 55nm, 59nm, 89nm, 123nm, 125nm or 129nm.

[0142] Therefore, the first sub-layer 371 can cause the light incident on it to undergo phase delay. The phase delay is within the range of the in-plane delay value and the thickness delay value. After the phase changes, the light is emitted and the polarization state of the light changes. In conjunction with the second sub-layer 372 and the third sub-layer 373, the amount of light emitted through the second polarizing layer 362 at a large viewing angle is reduced, which helps to reduce light leakage and color shift of the display panel.

[0143] In some examples, the second sublayer 372 is a +C type compensation layer. The refractive index of the second sublayer 372 satisfies: n z >n x =n y .

[0144] The third sublayer 373 is a -C type compensation layer. The refractive index of the third sublayer 373 satisfies: n x =n y >n z .

[0145] Therefore, the first linearly polarized light emitted from the first polarizing layer 361, after passing through the -B type compensation layer (i.e., the first sub-layer 371), is approximately converted into first elliptically polarized light. Then, it passes through the +C type compensation layer (i.e., the second sub-layer 372). Since the optical axis directions of the +C type compensation layer and the -B type compensation layer are different, the +C type compensation layer compensates for the first elliptically polarized light, causing a phase delay and converting it into second elliptically polarized light. Then, it passes through the -C type compensation layer (i.e., the third sub-layer 373). The optical axis direction of the -C type compensation layer is opposite to that of the +C type compensation layer, causing the second elliptically polarized light to be converted into second linearly polarized light. For example, the polarization direction of this second linearly polarized light is perpendicular or approximately perpendicular to the optical axis direction of the second polarizing layer 362. This second linearly polarized light can hardly pass through the second polarizing layer 362 and is emitted, thereby reducing the amount of light leakage of the display panel 3 in dark display conditions and reducing the color shift of the display panel 3 at wide viewing angles.

[0146] In some examples, the sum of the thickness retardation values ​​of the second sublayer 372 and the third sublayer 373 ranges from -117nm to -194nm.

[0147] For example, the sum of the thickness retardation values ​​of the second sublayer 372 and the third sublayer 373 ranges from -117nm to -177nm, -133nm to -193nm, -134nm to -194nm, -117nm to -194nm, -117nm to -155nm, or -155nm to -194nm.

[0148] For example, the sum of the thickness retardation values ​​of the second sublayer 372 and the third sublayer 373 can be -117nm, -133nm, -134nm, -155nm, -177nm, -193nm, or -194nm.

[0149] Therefore, the second sub-layer 372 and the third sub-layer 373 can cause the light incident on them to undergo phase delay. The amount of phase delay is within the sum of the aforementioned thickness delay values. After the phase changes, the light is emitted, and the polarization state of the light changes. In conjunction with the first sub-layer 371, the amount of light emitted through the second polarizing layer 362 at a large viewing angle is reduced, which helps to reduce light leakage and color shift of the display panel.

[0150] To create a Poincaré sphere from the light rays in the display panel in this example, see... Figure 9A and Figure 9B .

[0151] refer to Figure 9A and Figure 9BIn the Poincaré sphere diagram, position 1 represents the polarization state of the light emitted after the backlight passes through the first polarizing layer 361. Position 2 represents the polarization state of the light after passing through the first liquid crystal layer 32. The polarization state of the light does not change significantly after passing through the first liquid crystal layer 32; this light is approximately located near the equatorial EQT position of the Poincaré sphere, and is roughly linearly polarized. Position 3 represents the polarization state of the aforementioned linearly polarized light after passing through the first sublayer 371; this light is located far from the equatorial EQT position. It can be seen that after the compensation effect of the first sublayer 371, the linearly polarized light is converted into elliptically polarized light located below the equatorial EQT. Position 4 represents the polarization state of the first elliptically polarized light after passing through the second sublayer 372; this light is also far from the equatorial EQT position. It can be seen that after the compensation effect of the second sublayer 372, the elliptically polarized light is converted into elliptically polarized light located above the equatorial EQT. Position 5 represents the polarization state of the second elliptically polarized light after passing through the third sub-layer 373, and this light is located near the equatorial EQT position. It can be seen that after compensation by the third sub-layer 373, the second elliptically polarized light is roughly converted into second linearly polarized light located near the equatorial EQT. When this second linearly polarized light is incident on the second polarizing layer 362, less light is emitted, resulting in less light leakage and a lower degree of color shift in the display panel.

[0152] In other examples, the third sublayer 373 is the second target sublayer, and the third sublayer 373 is a +B type compensation layer. The refractive index of the third sublayer 373 satisfies: n z >n x >n y .

[0153] Therefore, the third sub-layer 373 can cause the incident light to undergo phase delay, thereby changing the polarization state of the light and thus helping to reduce light leakage and color shift of the display panel.

[0154] In some examples, the in-plane retardation of the third sublayer 373 ranges from 32 nm to 98 nm. The thickness retardation of the third sublayer 373 ranges from -259 nm to -334 nm.

[0155] For example, the in-plane delay value range of the third sublayer 373 can be 32nm~98nm, 35nm~95nm, 38nm~98nm, 35nm~98nm, 32nm~66nm or 66nm~98nm.

[0156] For example, the in-plane delay value of the third sublayer 373 can be 32nm, 35nm, 38nm, 66nm, 95nm or 98nm.

[0157] For example, the thickness retardation value range of the third sublayer 373 can be -259nm to -319nm, -266nm to -326nm, -274nm to -334nm, -259nm to -326nm, -266nm to -334nm, -259nm to -310nm, or -310nm to -334nm.

[0158] For example, the thickness retardation value of the third sublayer 373 can be -259nm, -266nm, -274nm, -259nm, -310nm, -326nm, -319nm or -334nm.

[0159] Therefore, the third sub-layer 373 can cause the light incident on it to undergo phase delay. The phase delay is within the range of the in-plane delay value and the thickness delay value. After the phase changes, the light is emitted and the polarization state of the light changes. In conjunction with the second sub-layer 372 and the first sub-layer 371, the amount of light emitted through the second polarizing layer 362 at a large viewing angle is reduced, which helps to reduce light leakage and color shift of the display panel.

[0160] In some examples, the first sublayer 371 is a -C type compensation layer. The refractive index of the first sublayer 371 satisfies: n x =n y >n z .

[0161] The second sublayer 372 is a +C type compensation layer. The refractive index of the second sublayer 372 satisfies: n z >n x =n y .

[0162] Therefore, the first linearly polarized light emitted from the first polarizing layer 361, after passing through the -C type compensation layer (i.e., the first sub-layer 371), is approximately converted into first elliptically polarized light. Then, it passes through the +C type compensation layer (i.e., the second sub-layer 372), whose optical axis direction is opposite to that of the -C type compensation layer. This causes the +C type compensation layer to compensate for the first elliptically polarized light, resulting in a phase delay and conversion into second elliptically polarized light. Then, it passes through the +B type compensation layer (i.e., the third sub-layer 373), whose optical axis direction is different from that of the +C type compensation layer. This causes the second elliptically polarized light to be converted into second linearly polarized light. For example, the polarization direction of this second linearly polarized light is perpendicular or approximately perpendicular to the optical axis direction of the second polarizing layer 362. This second linearly polarized light can hardly pass through the second polarizing layer 362 and is emitted, thereby reducing the amount of light leakage of the display panel 3 in dark display conditions and reducing the degree of color shift of the display panel 3 at wide viewing angles.

[0163] In some examples, the sum of the thickness retardation values ​​of the first sublayer 371 and the second sublayer 372 ranges from -185nm to -293nm.

[0164] For example, the sum of the thickness retardation values ​​of the first sublayer 371 and the thickness retardation values ​​of the second sublayer 372 can be in the range of -185nm to -245nm, -212nm to -272nm, -233nm to -293nm, -185nm to -272nm, -212nm to -293nm, -185nm to -254nm, or -254nm to -293nm.

[0165] For example, the sum of the thickness retardation value of the first sublayer 371 and the thickness retardation value of the second sublayer 372 can be -185nm, -212nm, -233nm, -245nm, -254nm, -272nm, -293nm or -293nm.

[0166] Therefore, the first sub-layer 371 and the second sub-layer 372 can cause the light incident on them to undergo phase delay. The amount of phase delay is within the sum of the above-mentioned thickness delay values. After the phase changes, the light is emitted, and the polarization state of the light changes. In conjunction with the third sub-layer 373, the amount of light emitted through the second polarizing layer 362 at a large viewing angle is reduced, which is beneficial to reducing light leakage and color shift of the display panel.

[0167] To create a Poincaré sphere from the light rays in the display panel in this example, see... Figure 10A and Figure 10B .

[0168] refer to Figure 10A and Figure 10BIn the Poincaré sphere diagram, position 1 represents the polarization state of the light emitted after the backlight passes through the first polarizing layer 361. Position 2 represents the polarization state of the light after passing through the first liquid crystal layer 32. The polarization state of the light does not change significantly after passing through the first liquid crystal layer 32; this light is approximately located near the equatorial EQT position of the Poincaré sphere, and is roughly linearly polarized. Position 3 represents the polarization state of the aforementioned linearly polarized light after passing through the first sublayer 371; this light is located far from the equatorial EQT position. It can be seen that after the compensation effect of the first sublayer 371, the linearly polarized light is converted into elliptically polarized light located below the equatorial EQT. Position 4 represents the polarization state of the first elliptically polarized light after passing through the second sublayer 372; this light is also far from the equatorial EQT position. It can be seen that after the compensation effect of the second sublayer 372, the elliptically polarized light is converted into elliptically polarized light located below the equatorial EQT. Position 5 represents the polarization state of the second elliptically polarized light after passing through the third sub-layer 373, and this light is located near the equatorial EQT position. It can be seen that after compensation by the third sub-layer 373, the second elliptically polarized light is roughly converted into second linearly polarized light located near the equatorial EQT. When this second linearly polarized light is incident on the second polarizing layer 362, less light is emitted, resulting in less light leakage and a lower degree of color shift in the display panel.

[0169] In addition, the inventors also tested the color shift and light leakage of the display panel provided in another possible implementation and the embodiments of this disclosure. The test results are shown in Tables 1 and 2.

[0170] Table 1

[0171] Table 2

[0172] Table 1 is a graph showing the color coordinates and brightness of the display panel in another possible implementation and several display panels in some embodiments of this disclosure; Table 2 is a graph showing the difference between the color coordinates and brightness of the display panel in another possible implementation and several display panels in some embodiments of this disclosure and the color coordinates and brightness at a normal viewing angle.

[0173] In Tables 1 and 2, the polarization angle is the deflection angle of the liquid crystal molecules in the first liquid crystal layer, which is 60° here. x and y are color coordinates, and y is the display brightness. +A+C indicates that in another possible implementation, the first compensation layer 371' in the display panel is a +A type compensation layer and the second compensation layer 372' is a +C type compensation layer. +A+CC indicates that in some embodiments of this disclosure, the first sub-layer 371 is a +A type compensation layer, the second sub-layer 372 is a +C type compensation layer, and the third sub-layer 373 is a -C type compensation layer in the display panel. +B+CC indicates that in some embodiments of this disclosure, the first sub-layer 371 is a +B type compensation layer, the second sub-layer 372 is a +C type compensation layer, and the third sub-layer 373 is a -C type compensation layer in the display panel. -B+CC indicates the detection results of the first sub-layer 371 being a -B type compensation layer, the second sub-layer 372 being a +C type compensation layer, and the third sub-layer 373 being a -C type compensation layer in the display panel of some embodiments of this disclosure. +C-C+A indicates the detection results of the first sub-layer 371 being a +C type compensation layer, the second sub-layer 372 being a -C type compensation layer, and the third sub-layer 373 being a +A type compensation layer in the display panel of some embodiments of this disclosure. -C+C+B indicates the detection results of the first sub-layer 371 being a -C type compensation layer, the second sub-layer 372 being a +C type compensation layer, and the third sub-layer 373 being a +B type compensation layer in the display panel of some embodiments of this disclosure. Azimuth angle refers to different angles located in the four quadrants. Table 1 shows the color coordinates and luminance values ​​of different display panels at different azimuth angles, and Table 2 shows the differences between the color coordinates and luminance of the display panels at different azimuth angles and the color coordinates and luminance at the normal viewing angle. At a normal viewing angle, the color coordinates and brightness of the display panel are: x=0.2958, y=0.2867, y=0.0207.

[0174] As can be seen from Table 2, the difference between the color coordinates of the display panel and the coordinates of the viewer looking directly at the screen is larger in another possible implementation, while the difference between the color coordinates of the display panel and the coordinates of the viewer looking directly at the screen is relatively smaller in the embodiments of this disclosure. This indicates that the display panel provided by the embodiments of this disclosure has a lower degree of color shift, and the color shift phenomenon is alleviated. The difference between the brightness of the display panel and the brightness at the viewing angle is larger in another possible implementation, while the difference between the brightness of the display panel and the brightness at the viewing angle is relatively smaller in the embodiments of this disclosure. This indicates that the display panel provided by the embodiments of this disclosure has less light leakage, and the light leakage phenomenon is effectively alleviated.

[0175] In some examples, the material of the aforementioned -C type compensation layer in compensation layer 37 includes cellulose triacetate.

[0176] Therefore, compared with the above-mentioned possible implementation, the use of acrylic or COP materials can be reduced, thereby alleviating the problem of raw material supply shortage and reducing the manufacturing cost of display panel 3.

[0177] For example, a membrane containing cellulose triacetate material can be stretched laterally or longitudinally to form a -C type compensation layer.

[0178] In some of the examples above, the first sublayer 371 or the second sublayer 372 in the compensation layer 37 is a +C type compensation layer, wherein the +C type compensation layer includes a cured second liquid crystal film.

[0179] Therefore, by using a cured second liquid crystal film material to form a +C type compensation layer, compared with the above-mentioned possible implementation method, the use of acrylic or COP materials can be reduced, thereby alleviating the problem of raw material supply shortage and reducing the manufacturing cost of display panel 3.

[0180] For example, the above-mentioned +A type compensation layer also includes a cured second liquid crystal film, thereby further reducing the use of acrylic or COP materials, which can alleviate the problem of tight raw material supply and reduce the manufacturing cost of display panel 3.

[0181] The aforementioned +C type compensation layer can also be made of COP material or TAC material. The -B type compensation layer can also be made of COP material or TAC material.

[0182] The above description is merely a specific embodiment of this disclosure, but the scope of protection of this disclosure is not limited thereto. Any variations or substitutions conceived by those skilled in the art within the scope of the technology disclosed in this disclosure should be included within the scope of protection of this disclosure. Therefore, the scope of protection of this disclosure should be determined by the scope of the claims.

Claims

1. A display panel, characterized in that, include: The first polarizer, the array substrate, the first liquid crystal layer, the opposing substrate, and the second polarizer are stacked in sequence. Both the first polarizer and the second polarizer include a polarizing layer, and the optical axis direction of the polarizing layer in the first polarizer is perpendicular to the optical axis direction of the polarizing layer in the second polarizer. One of the first polarizer and the second polarizer further includes: a compensation layer; the compensation layer is located on the side of the polarizer closer to the first liquid crystal layer; the compensation layer is used to compensate for the phase delay of light transmitted through the compensation layer; The compensation layer includes a first sub-layer, a second sub-layer, and a third sub-layer stacked sequentially, wherein the third sub-layer is the sub-layer closest to the light-emitting side of the display panel; the optical axis direction of the first sub-layer intersects with the optical axis direction of the polarizing layer in the first polarizer, the optical axis direction of the second sub-layer is perpendicular to the optical axis direction of the polarizing layer in the first polarizer, and the optical axis direction of the third sub-layer intersects with the optical axis direction of the polarizing layer in the second polarizer.

2. The display panel according to claim 1, characterized in that, One of the first sublayer and the third sublayer is the first target sublayer; the first target sublayer is a +A type compensation layer; the refractive index of the first target sublayer satisfies: n x >n y =n z ; where n x Let n be the refractive index of light in the X direction of the plane containing the first target sublayer. y Let n be the refractive index of light in the Y direction of the plane containing the first target sublayer. z Let Z be the refractive index of light in the thickness direction Z of the first target sublayer.

3. The display panel according to claim 2, characterized in that, The in-plane retardation value of the first target sublayer is λ / 4, and the thickness retardation value of the first target sublayer is λ / 8; where λ is the wavelength of visible light.

4. The display panel according to claim 2 or 3, characterized in that, The first sub-layer is the first target sub-layer; The second sublayer is a +C type compensation layer, and the refractive index of the second sublayer satisfies: n z >n x =n y ; The third sublayer is a -C type compensation layer; the refractive index of the third sublayer satisfies: n x =n y >n z .

5. The display panel according to claim 4, characterized in that, The sum of the thickness delay values ​​of the second sublayer and the third sublayer ranges from -109nm to -178nm.

6. The display panel according to claim 2 or 3, characterized in that, The third sub-layer is the first target sub-layer; The first sublayer is a +C type compensation layer, and the refractive index of the first sublayer satisfies: n z >n x =n y ; The second sublayer is a -C type compensation layer; the refractive index of the second sublayer satisfies: n x =n y >n z .

7. The display panel according to claim 6, characterized in that, The sum of the thickness retardation values ​​of the first sublayer and the second sublayer ranges from -94nm to -187nm.

8. The display panel according to claim 1, characterized in that, One of the first sub-layer and the third sub-layer is the second target sub-layer; the second target sub-layer is a dual-optical-axis compensation layer.

9. The display panel according to claim 8, characterized in that, The first sub-layer is the second target sub-layer, and the first sub-layer is a -B type compensation layer; The refractive index of the first sublayer satisfies: n x >n y >n z .

10. The display panel according to claim 9, characterized in that, The in-plane retardation value of the first sublayer ranges from 89nm to 156nm; the thickness retardation value of the first sublayer ranges from 53nm to 129nm.

11. The display panel according to claim 9 or 10, characterized in that, The second sublayer is a +C type compensation layer; the refractive index of the second sublayer satisfies: n z >n x =n y ; The third sublayer is a -C type compensation layer; the refractive index of the third sublayer satisfies: n x =n y >n z .

12. The display panel according to claim 11, characterized in that, The sum of the thickness retardation values ​​of the second sublayer and the third sublayer ranges from -117nm to -194nm.

13. The display panel according to claim 8, characterized in that, The third sub-layer is the second target sub-layer, and the third sub-layer is a +B type compensation layer; The refractive index of the third sublayer satisfies: n z >n x >n y .

14. The display panel according to claim 13, characterized in that, The in-plane retardation value of the third sublayer ranges from 32nm to 98nm; the thickness retardation value of the third sublayer ranges from -259nm to -334nm.

15. The display panel according to claim 13 or 14, characterized in that, The first sublayer is a -C type compensation layer; the refractive index of the first sublayer satisfies: n x =n y >n z ; The second sublayer is a +C type compensation layer; the refractive index of the second sublayer satisfies: n z >n x =n y .

16. The display panel according to claim 15, characterized in that, The sum of the thickness retardation values ​​of the first sublayer and the second sublayer ranges from -185nm to -293nm.

17. The display panel according to claim 1, characterized in that, In the compensation layer, at least one sublayer is made of cellulose triacetate.

18. The display panel according to claim 1, characterized in that, In the compensation layer, the material of the -C type compensation layer includes cellulose triacetate.

19. The display panel according to claim 1, characterized in that, In the compensation layer, the first sub-layer or the second sub-layer is a +C type compensation layer, and the +C type compensation layer includes a cured second liquid crystal film.

20. The display panel according to claim 1, characterized in that, The other of the first polarizer and the second polarizer further includes a protective layer; the protective layer is located on the side of the polarizer close to the first liquid crystal layer; the material of the protective layer includes cellulose triacetate.

21. A display device, characterized in that, include: The display panel as described in any one of claims 1 to 20, and the backlight module located on the non-light-emitting side of the display panel.

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