OLED display panel, display device and preparation method thereof

Abstract

The invention relates to the technical field of display panels, in particular to a display panel and a preparation method thereof, and aims to solve the problem that an existing display panel applying a CLC technology is large in color difference. In order to achieve the purpose, a hue adjusting layer is arranged in the display panel, the transmittance of the hue adjusting layer to first color light is larger than the transmittance of the hue adjusting layer to second color light and third color light, and the transmittance of a cholesteric liquid crystal layer to the first color light is smaller than the transmittance of the cholesteric liquid crystal layer to the second color light and the third color light. After external ambient light passes through the hue adjusting layer and the cholesteric liquid crystal layer, the light intensity of red light, blue light and green light in reflected light of the OLED screen can be equivalent, and the purpose of improving the reflected hue is achieved.

Description

Technical Field

[0001] The present disclosure relates to the technical field of display panels, and specifically provides a display panel and a method for manufacturing the same. Background Art

[0002] In order to reduce the reflection of the screen to ambient light, an OLED display panel generally has a polarizer disposed on the light-emitting side, and the polarizer is used to reduce the reflection intensity of external ambient light on the screen. However, the polarizer also reduces the light-emitting efficiency of the OLED device.

[0003] In order to improve the light-emitting efficiency of the OLED device, the industry has proposed the CLC (Cholesteric Liquid Crystals) technology. Cholesteric liquid crystal is a liquid crystal phase with a self-assembled helical structure, and has a high transmittance for visible light in a specific wavelength band. This causes the light in the wavelength band with a high transmittance to be stronger after the external ambient light first passes through the cholesteric liquid crystal and then is reflected by the OLED device layer, resulting in a large color difference in the display panel. Summary of the Invention

[0004] The present disclosure aims to solve the above technical problems, that is, to solve the problem of large color difference in the existing display panel using the CLC technology.

[0005] In a first aspect, the present disclosure provides an OLED display panel, including: a substrate; an OLED device layer, including a first-color light-emitting element, a second-color light-emitting element, and a third-color light-emitting element, located on the display side of the substrate; a cholesteric liquid crystal layer, located on a side of the OLED device layer away from the substrate, the cholesteric liquid crystal layer being configured to have a transmittance for the first-color light less than the transmittances for the second-color light and the third-color light; a polarizer, located on a side of the cholesteric liquid crystal layer away from the substrate; and a hue adjustment layer, located on a side of the OLED device layer away from the substrate, the hue adjustment layer being configured to have a transmittance for the first-color light greater than the transmittances for the second-color light and the third-color light.

[0006] In some exemplary embodiments, the orthographic projections of the first-color light-emitting element, the second-color light-emitting element, and the third-color light-emitting element on the substrate do not overlap with the orthographic projection of the hue adjustment layer on the substrate.

[0007] In some exemplary embodiments, the display panel further includes a black matrix, the black matrix is disposed on a side of the first-color light-emitting element away from the substrate, and the orthographic projection of the black matrix on the substrate surrounds the orthographic projection of the first-color light-emitting element on the substrate.

[0008] In some exemplary embodiments, the black matrix is located between the hue adjustment layer and the substrate.

[0009] In some exemplary embodiments, at least a part of the positive projection of the first color light-emitting element on the substrate falls within the positive projection range of the hue adjustment layer on the substrate, and the positive projections of the second color light-emitting element and the third color light-emitting element on the substrate do not overlap with the positive projection of the hue adjustment layer on the substrate.

[0010] In some exemplary embodiments, the hue adjustment layer is located between the OLED device layer and the cholesteric liquid crystal layer.

[0011] In some exemplary embodiments, the display panel further includes a touch layer, the touch layer is located between the cholesteric liquid crystal layer and the substrate; the hue adjustment layer is located between the touch layer and the cholesteric liquid crystal layer; or, the hue adjustment layer is located between the touch layer and the substrate; or, the hue adjustment layer is located within the touch layer.

[0012] In some exemplary embodiments, the display panel further includes a packaging layer, the packaging layer is located on a side of the OLED device layer away from the substrate, and the hue adjustment layer is located on a side of the packaging layer away from the substrate; and / or, the display panel further includes a planarization layer, the planarization layer is located on a side of the hue adjustment layer away from the substrate.

[0013] In some exemplary embodiments, the first color light is any one of red light, green light, and blue light.

[0014] In a second aspect, the present disclosure provides a method for manufacturing an OLED display panel, including: providing a substrate; forming an OLED device layer, the OLED device layer includes a first color light-emitting element, a second color light-emitting element, and a third color light-emitting element located on a display side of the substrate; forming a cholesteric liquid crystal layer, the cholesteric liquid crystal layer is located on a side of the OLED device layer away from the substrate and is configured to have a transmittance of the first color light less than the transmittances of the second color light and the third color light; forming a polarizer, the polarizer is located on a side of the cholesteric liquid crystal layer away from the substrate; forming a hue adjustment layer, the hue adjustment layer is located on a side of the OLED device layer away from the substrate and is configured to have a transmittance of the first color light greater than the transmittances of the second color light and the third color light.

[0015] In a third aspect, the present disclosure provides a display device, including the OLED display panel as described above or the OLED display panel manufactured by the method as described above.

[0016] Compared with the prior art, the present disclosure has at least the following beneficial effects:

[0017] A hue adjustment layer is set in the display panel. The transmittance of the hue adjustment layer to the first color light is greater than that to the second color light and the third color light. The transmittance of the cholesteric liquid crystal layer to the first color light is less than that to the second color light and the third color light. After the external ambient light passes through the hue adjustment layer and the cholesteric liquid crystal layer, the light intensities of red light, blue light, and green light in the reflected light of the OLED screen can be made equivalent, achieving the purpose of improving the reflected hue. Description of the Drawings

[0018] The preferred embodiments of the present disclosure will be described below with reference to the accompanying drawings, in which:

[0019] Figure 1 is a cross-sectional view of a display panel;

[0020] Figure 2 is a cross-sectional view of a display panel provided by the present disclosure;

[0021] Figure 3 is a cross-sectional view of another display panel provided by the present disclosure;

[0022] Figure 4 is a cross-sectional view of yet another display panel provided by the present disclosure;

[0023] Figure 5 is a cross-sectional view of still another display panel provided by the present disclosure;

[0024] Figures 6A to 6B is Figure 2 a cross-sectional view of the shown display panel during the manufacturing process.

[0025] Description of the Reference Numerals:

[0026] 1. Substrate; 2. Driving device layer; 3. OLED device layer; 31. Pixel defining layer; EL1. First color light-emitting element; EL2. Second color light-emitting element; EL3. Third color light-emitting element; 32. Anode; 33. Electroluminescent layer; 34. Cathode; 4. Encapsulation layer; 5. Touch layer; 6. Black matrix; 7. Hue adjustment layer; 71. Flat layer; 8. Cholesteric liquid crystal layer; 9. Polarizer. Detailed Embodiments

[0027] The preferred embodiments of the present disclosure will be described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are only used to explain the technical principles of the present disclosure and are not intended to limit the protection scope of the present disclosure.

[0028] It should be noted that in the description of the present disclosure, the terms indicating directions or positional relationships such as "upper", "lower", "left", "right", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings. This is only for convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation on the present disclosure. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0029] In addition, it should also be noted that in the description of the present disclosure, unless otherwise clearly specified and limited, the terms "mounted", "set", "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, and can also be the communication inside two elements. For those skilled in the art, the specific meanings of the above terms in the present disclosure can be understood according to specific situations.

[0030] Figure 1 It is a cross-sectional view of a display panel.

[0031] As Figure 1 shown, the display panel includes a substrate 1, and a driving device layer 2, an OLED device layer 3, a cholesteric liquid crystal layer 8, and a polarizer 9 are sequentially arranged on the display side of the substrate 1.

[0032] The polarizer 9 uses the principle of polarized light and can transmit light with the same polarization direction as the polarizer 9. The light with a polarization direction inconsistent with the polarizer 9 is absorbed and converted into heat energy or other forms of energy after being absorbed. After the external ambient light enters the display panel through the polarizer, the light intensity will be reduced by half, thereby reducing the reflection intensity of the ambient light.

[0033] The cholesteric liquid crystal in the cholesteric liquid crystal layer 8 is a liquid crystal phase with a self-assembled helical structure, and the liquid crystal molecules in it are arranged in a rotating manner along the helical axis. Because the cholesteric liquid crystal molecules have a high birefringence, the periodic arrangement of such liquid crystal molecules makes the effective refractive index of the liquid crystal also show periodic changes, thereby forming a photonic band gap, which is equivalent to a one-dimensional photonic crystal. The cholesteric liquid crystal layer 8 can transmit circularly polarized light with a helicity opposite to its own and reflect circularly polarized light with the same helicity as its own. The light emitted by the OLED device, the circularly polarized light with a helicity opposite to that of the cholesteric liquid crystal layer 8, can all pass through the polarizer 9 and be emitted after passing through the cholesteric liquid crystal layer 8. The circularly polarized light with a helicity opposite to that of the cholesteric liquid crystal layer 8 is reflected and directed towards the OLED device, and then is reflected by the cathode 34 in the OLED device again to change its helicity, so that it can pass through the cholesteric liquid crystal layer 8 and the polarizer 9, achieving the purpose of improving the light extraction efficiency of the OLED device and reducing the power consumption of the OLED device on the premise of achieving the same light emission intensity.

[0034] While the cholesteric liquid crystal layer 8 increases the transmittance of the emitted light in certain wavelength bands, the transmittance of the light in this wavelength band in the external ambient light through the polarizer 9 and the cholesteric liquid crystal layer 8 will also increase. The light passing through the polarizer 9 and the cholesteric liquid crystal layer 8 is reflected between the cathode 34 and the cholesteric liquid crystal layer 8 and then transmitted out from the cholesteric liquid crystal layer 8 and the polarizer 9. For example, if the transmittance of the cholesteric liquid crystal layer 8 to green light and blue light is greater than that to red light, then the proportion of green light and blue light in the external ambient light passing through the polarizer 9 and the cholesteric liquid crystal layer 8 is relatively large. After being reflected by the cathode 34 and then emitted from the cholesteric liquid crystal layer 8 and the polarizer 9, the hue of the reflected light of the OLED screen is bluish-green, resulting in a relatively large difference in reflected color phase.

[0035] Based on this, the present disclosure provides an OLED display panel, including: a substrate; an OLED device layer, including a first-color light-emitting element, a second-color light-emitting element, and a third-color light-emitting element, located on the display side of the substrate; a cholesteric liquid crystal layer, located on the side of the OLED device layer away from the substrate, the cholesteric liquid crystal layer being configured to have a transmittance to the first-color light less than that to the second-color light and the third-color light; a polarizer, located on the side of the cholesteric liquid crystal layer away from the substrate; and a hue adjustment layer, located on the side of the OLED device layer away from the substrate, the hue adjustment layer being configured to have a transmittance to the first-color light greater than that to the second-color light and the third-color light.

[0036] Hereinafter, the display panel and the manufacturing method according to some embodiments of the present disclosure will be described through several specific embodiments.

[0037] Figure 2 is a cross-sectional view of a display panel provided by the present disclosure.

[0038] As Figure 2 shown, the display panel includes a substrate 1, on which a driving device layer 2 and an OLED device layer 3 are provided. A pixel driving circuit is provided in the driving device layer 2, and the pixel driving circuit is used to drive the OLED device layer 3 to emit light.

[0039] The OLED device layer 3 has a light-emitting element and a pixel defining layer 31. The light-emitting element includes an anode 32, an electroluminescent layer 33, and a cathode 34. The pixel defining layer 31 defines an opening exposing the anode 32. The electroluminescent layer 33 is located within the opening, and the cathode 34 is disposed over the entire surface to cover the pixel defining layer 31 and the electroluminescent layer 33. Among them, the light-emitting elements are divided into a first-color light-emitting element EL1, a second-color light-emitting element EL2, and a third-color light-emitting element EL3. The pixel driving circuit and the corresponding light-emitting element (one of the first-color light-emitting element EL1, the second-color light-emitting element EL2, and the third-color light-emitting element EL3) are called sub-pixels, and each pixel region has sub-pixels of three colors (such as red, green, and blue).

[0040] It should be specifically noted that the cathode 34 provided on the entire surface is used as a common electrode. Unless otherwise specified, the area where the light-emitting element is located in the present disclosure refers to the electroluminescent layer 33, the part of the cathode 34 located thereon, and the part of the anode 32 located thereunder.

[0041] On the side of the OLED device layer 3 away from the substrate 1, a hue adjustment layer 7, a cholesteric liquid crystal layer 8, and a polarizer 9 are sequentially provided. The cholesteric liquid crystal layer 8 is configured such that the transmittance of the first color light is less than the transmittance of the second color light and the third color light. The hue adjustment layer 7 is configured such that the transmittance of the first color light is greater than the transmittance of the second color light and the third color light. Among them, the first color light can be any one of red light, green light, and blue light.

[0042] Since the transmittance of the first color light through the cholesteric liquid crystal layer 8 is less than the transmittance of the second color light and the third color light, after the external ambient light passes through the polarizer 9 and the cholesteric liquid crystal layer 8, the light intensity of the first color light is weaker, and the light intensity of the second color light and the third color light is stronger. Also, since the transmittance of the first color light through the hue adjustment layer 7 is greater than the transmittance of the second color light and the third color light, after the external ambient light passes through the hue adjustment layer 7, the light intensity of the first color light is stronger, and the light intensity of the second color light and the third color light is weaker. Under the combined action of the cholesteric liquid crystal layer 8 and the hue adjustment layer 7, it is possible to make the light intensities of red light, blue light, and green light in the reflected light of the OLED screen equivalent, achieving the purpose of improving the reflected hue.

[0043] For example, a packaging layer 4 is provided on the side of the OLED device layer 3 away from the substrate 1, and the hue adjustment layer 7 is located on the side of the packaging layer 4 away from the OLED device layer 3. For example, a planarization layer 71 is provided on the side of the hue adjustment layer 7 away from the substrate 1 to planarize the surface, facilitating the subsequent setting of the cholesteric liquid crystal layer 8 and the polarizer 9.

[0044] Figure 3 It is a cross-sectional view of another display panel provided by the present disclosure.

[0045] For example, as Figure 5 shown, the display panel further includes a touch layer 5, and the touch layer 5 is located between the cholesteric liquid crystal layer 8 and the substrate 1. For example, the hue adjustment layer 7 is located between the touch layer 5 and the cholesteric liquid crystal layer 8. Of course, the hue adjustment layer 7 can also be provided between the touch layer 5 and the substrate 1, or the hue adjustment layer 7 is located within the touch layer 5.

[0046] In some possible examples, as Figure 2As shown, the orthographic projections of the first-color light-emitting element EL1, the second-color light-emitting element EL2, and the third-color light-emitting element EL3 on the substrate 1 do not overlap with the orthographic projection of the hue adjustment layer 7 on the substrate 1. That is, the hue adjustment layer 7 covers the pixel defining layer 31 and exposes the first-color light-emitting element EL1, the second-color light-emitting element EL2, and the third-color light-emitting element EL3, ensuring that the hue adjustment layer 7 does not reduce the light extraction efficiency of the first-color light-emitting element EL1, the second-color light-emitting element EL2, and the third-color light-emitting element EL3.

[0047] Figure 4 is a cross-sectional view of another display panel provided by the present disclosure.

[0048] In some other possible examples, as Figure 4 shown, the orthographic projections of the first-color light-emitting element EL1, the second-color light-emitting element EL2, and the third-color light-emitting element EL3 on the substrate 1 do not overlap with the orthographic projection of the hue adjustment layer 7 on the substrate 1, and the display panel further includes a black matrix 6. The black matrix 6 is disposed on a side of the first-color light-emitting element EL1 away from the substrate 1, and the orthographic projection of the black matrix 6 on the substrate 1 surrounds the orthographic projection of the first-color light-emitting element EL1 on the substrate 1. For example, the black matrix 6 is located between the hue adjustment layer 7 and the substrate 1.

[0049] Since the hue adjustment layer 7 exposes the first-color light-emitting element EL1, the second-color light-emitting element EL2, and the third-color light-emitting element EL3, the external ambient light that passes through the polarizer 9 and the cholesteric liquid crystal layer 8 and is incident on the first-color light-emitting element EL1, the second-color light-emitting element EL2, and the third-color light-emitting element EL3 does not pass through the hue adjustment layer 7, and the color of this part of the light tends to the second color and the third color. The black matrix 6 can reduce the ambient light incident on the first-color light-emitting element EL1, and at the same time can also reduce the ambient light reflected from the first-color light-emitting element EL1 to the outside, reducing the intensity of the second-color light and the third-color light in the light reflected from the first-color light-emitting element EL1, thereby further improving the hue of the reflected light.

[0050] Figure 5 is a cross-sectional view of yet another display panel provided by the present disclosure.

[0051] In still some other possible examples, as Figure 5As shown, at least a part of the positive projection of the first-color light-emitting element EL1 on the substrate 1 falls within the range of the positive projection of the hue adjustment layer 7 on the substrate 1, and the positive projections of the second-color light-emitting element EL2 and the third-color light-emitting element EL3 on the substrate 1 do not overlap with the positive projection of the hue adjustment layer 7 on the substrate 1. That is, the hue adjustment layer 7 covers at least a part of the first-color light-emitting element EL1 and the pixel definition layer 31 and exposes the second-color light-emitting element EL2 and the third-color light-emitting element EL3. Since the hue adjustment layer 7 covers the pixel definition layer 31 and at least a part of the first-color light-emitting element EL1, the external ambient light incident on at least a part of the first-color light-emitting element EL1 and the pixel definition layer 31 will pass through the polarizer 9, the cholesteric liquid crystal layer 8, and the hue adjustment layer 7 simultaneously, making the light intensities of red, blue, and green in the reflected light of the OLED screen equivalent, achieving the purpose of improving the reflected hue.

[0052] For example, the transmittance of the hue adjustment layer 7 to the first-color light is close to 100%, and the transmittances to the second-color light and the third-color light are close to 0. At this time, the hue adjustment layer 7 can completely transmit the light emitted from the first-color light-emitting element EL1 without reducing the light extraction efficiency of the first-color light-emitting element EL1.

[0053] To facilitate understanding of the content of the present disclosure, several specific examples are provided below for comparison.

[0054] Example 1

[0055] As Figure 1 shown, the display panel includes a substrate 1, on which a driving device layer 2, an OLED device layer 3, a packaging layer 4, a cholesteric liquid crystal layer 8, and a polarizer 9 are sequentially provided. Among them, the transmittance of the cholesteric liquid crystal layer 8 to red light is less than the transmittances to blue light and green light.

[0056] After the external ambient light is incident on the display panel, it first passes through the polarizer 9 and the cholesteric liquid crystal layer 8, then is reflected by the cathode 34 in the OLED device layer 3, and then passes through the cholesteric liquid crystal layer 8 and the polarizer 9 and exits, forming the reflected light of the display panel. Since the transmittance of the cholesteric liquid crystal layer 8 to red light is less than the transmittances to blue light and green light, the reflected light is bluish-green.

[0057] In the LAB (Lab color space) chromaticity space, the hue of the reflected light is a* = -16.66, b* = -3.34. Among them, a* represents the hue deviation from green to red, a negative value indicates that the hue is greenish, and a positive value indicates that the hue is reddish; b* represents the hue deviation from blue to yellow, a negative value indicates that the hue is bluish, and a positive value indicates that the hue is yellowish.

[0058] Example 2

[0059] As Figure 2As shown in the figure, the display panel includes a substrate 1, on which a driving device layer 2, an OLED device layer 3, a packaging layer 4, a hue adjustment layer 7, a planarization layer 71, a cholesteric liquid crystal layer 8, and a polarizer 9 are sequentially arranged. Among them, the transmittance of the cholesteric liquid crystal layer 8 to red light is less than that to blue light and green light, and the transmittance of the hue adjustment layer 7 to red light is greater than that to blue light and green light. The hue adjustment layer 7 covers the pixel defining layer 31 and exposes the red light-emitting element, the green light-emitting element, and the blue light-emitting element.

[0060] The external ambient light incident on the non-light-emitting area (i.e., the area where the pixel defining layer 31 is located) first passes through the polarizer 9, the cholesteric liquid crystal layer 8, and the hue adjustment layer 7, and then is reflected by the cathode 34 in the OLED device layer 3. After passing through the hue adjustment layer 7, the cholesteric liquid crystal layer 8, and the polarizer 9 again, it is emitted to form the reflected light of the display panel. Since the transmittance of the cholesteric liquid crystal layer 8 to red light is less than that to blue light and green light, and the transmittance of the hue adjustment layer 7 to red light is greater than that to blue light and green light, the intensities of the red light, blue light, and green light of the ambient light after passing through the cholesteric liquid crystal layer 8 and the hue adjustment layer 7 are comparable, which helps to improve the hue of the reflected light of the display panel.

[0061] In the LAB color space, the hue of the reflected light is a* = -2.5 and b* = 0.

[0062] Example 3

[0063] As Figure 4 As shown in the figure, the display panel includes a substrate 1, on which a driving device layer 2, an OLED device layer 3, a packaging layer 4, a hue adjustment layer 7, a planarization layer 71, a cholesteric liquid crystal layer 8, and a polarizer 9 are sequentially arranged. Among them, the transmittance of the cholesteric liquid crystal layer 8 to red light is less than that to blue light and green light, and the transmittance of the hue adjustment layer 7 to red light is greater than that to blue light and green light. The hue adjustment layer 7 covers the pixel defining layer 31 and exposes the red light-emitting element, the green light-emitting element, and the blue light-emitting element.

[0064] A black matrix 6 is provided on the red light-emitting element of the display panel. The orthographic projection of the black matrix 6 on the substrate 1 surrounds the orthographic projection of the red light-emitting element on the substrate 1, that is, the black matrix 6 is provided on the red light-emitting element and exposes the red light-emitting element.

[0065] The external ambient light incident on the non-emitting region (i.e., the region where the pixel defining layer 31 is located) first passes through the polarizer 9, the cholesteric liquid crystal layer 8, and the hue adjustment layer 7, and then is reflected by the cathode 34 in the OLED device layer 3. After passing through the hue adjustment layer 7, the cholesteric liquid crystal layer 8, and the polarizer 9 again, it is emitted, forming the reflected light of the display panel. Since the transmittance of the cholesteric liquid crystal layer 8 to red light is less than that to blue light and green light, and the transmittance of the hue adjustment layer 7 to red light is greater than that to blue light and green light, the intensities of red light, blue light, and green light of the ambient light after passing through the cholesteric liquid crystal layer 8 and the hue adjustment layer 7 are comparable, which helps to improve the hue of the reflected light of the display panel.

[0066] The external ambient light incident on the red light-emitting element first passes through the polarizer 9 and the cholesteric liquid crystal layer 8, and then part of the light is blocked and absorbed by the black matrix 6, and the remaining light is incident on the cathode 34 and reflected by the cathode 34. Then, part of the light is absorbed by the black matrix 6 again, and the remaining light is emitted from the opening of the black matrix 6. The hue of this part of the light is bluish-green. By setting the black matrix 6, the intensity of the reflected light of the ambient light at the red light-emitting element can be reduced, thereby improving the hue of the reflected light as a whole.

[0067] In the LAB color space, the hue of the reflected light is a* = -1.8 and b* = -0.3.

[0068] Example 4

[0069] As Figure 5 shown, the display panel includes a substrate 1, on which a driving device layer 2, an OLED device layer 3, a packaging layer 4, a hue adjustment layer 7, a flat layer 71, a cholesteric liquid crystal layer 8, and a polarizer 9 are sequentially arranged. Among them, the transmittance of the cholesteric liquid crystal layer 8 to red light is less than that to blue light and green light, and the transmittance of the hue adjustment layer 7 to red light is greater than that to blue light and green light. The hue adjustment layer 7 covers the pixel defining layer 31 and the red light-emitting element and exposes the green light-emitting element and the blue light-emitting element.

[0070] The transmittance of the hue adjustment layer 7 to red light is close to 100%, and the transmittance to blue light and green light is close to 0.

[0071] The external ambient light incident on the non-emitting region (i.e., the region where the pixel defining layer 31 is located) and the red light-emitting element first passes through the polarizer 9, the cholesteric liquid crystal layer 8, and the hue adjustment layer 7, and then is reflected by the cathode 34 in the OLED device layer 3. After passing through the hue adjustment layer 7, the cholesteric liquid crystal layer 8, and the polarizer 9 again, it is emitted, forming the reflected light of the display panel. Since the transmittance of the cholesteric liquid crystal layer 8 to red light is less than that to blue light and green light, and the transmittance of the hue adjustment layer 7 to red light is greater than that to blue light and green light, the intensities of red light, blue light, and green light of the ambient light after passing through the cholesteric liquid crystal layer 8 and the hue adjustment layer 7 are comparable, which helps to improve the hue of the reflected light of the display panel.

[0072] In the LAB color space representation, the hue of the reflected light is a* = -1.3 and b* = 0.2.

[0073] According to Example 1 and Example 2, it can be seen that the setting of the hue adjustment layer 7 can reduce the proportion of blue light and green light in the reflected light of the external ambient light on the display panel, thereby achieving the purpose of significantly improving the hue of the reflected light.

[0074] According to Example 2 and Example 3, it can be seen that only the ambient light reflected at the red light-emitting element, blue light-emitting element, and green light-emitting element passes through the cholesteric liquid crystal layer 8 and does not pass through the hue adjustment layer 7, and the hue deviation of the reflected light mainly exists due to this. By providing a black matrix 6 on the red light-emitting element, the light intensity of the external ambient light entering and exiting at the red light-emitting element can be reduced, thereby reducing the light intensity of the light reflected from the red light-emitting element to further improve the hue of the reflected light.

[0075] According to Example 2 and Example 4, it can be seen that covering the cholesteric liquid crystal layer 8 on the red light-emitting element as well can increase the coverage range of the cholesteric liquid crystal layer 8, and the proportions of red light, green light, and blue light in the ambient light reflected from the red light-emitting element are quite equal, which can further improve the hue of the reflected light.

[0076] The present disclosure also provides a method for manufacturing an OLED display panel, including: providing a substrate; forming an OLED device layer, the OLED device layer including a first color light-emitting element, a second color light-emitting element, and a third color light-emitting element located on the display side of the substrate; forming a cholesteric liquid crystal layer, the cholesteric liquid crystal layer being located on the side of the OLED device layer away from the substrate and being configured to have a transmittance of the first color light less than the transmittance of the second color light and the third color light; forming a polarizer, the polarizer being located on the side of the cholesteric liquid crystal layer away from the substrate; forming a hue adjustment layer, the hue adjustment layer being located on the side of the OLED device layer away from the substrate and being configured to have a transmittance of the first color light greater than the transmittance of the second color light and the third color light.

[0077] Next, taking Figure 2 the display panel with the structure shown as an example, the method for manufacturing the display panel will be described.

[0078] As Figure 6A shown, a substrate 1 is provided, and a driving device layer 2, an OLED device layer 3, and a packaging layer 4 are sequentially formed on the substrate 1. Among them, the OLED device layer 3 includes a pixel definition layer 31, the pixel definition layer 31 defines a first color light-emitting element EL1, a second color light-emitting element EL2, and a third color light-emitting element EL3, and the driving circuit layer is used to drive the first color light-emitting element EL1, the second color light-emitting element EL2, and the third color light-emitting element EL3 to emit light.

[0079] For example, when the display panel is a flexible display panel, the provided substrate 1 can be a flexible substrate such as polyimide (PI). When the display panel is a rigid display panel, the substrate 1 can be a rigid substrate such as glass or quartz.

[0080] As Figure 6B As shown, a hue adjustment layer 7 is formed on the encapsulation layer 4 by a patterning process. The hue adjustment layer 7 covers the pixel definition layer 31, exposing the first color light-emitting element EL1, the second color light-emitting element EL2, and the third color light-emitting element EL3. The transmittance of the hue adjustment layer 7 to the first color light is greater than the transmittance to the second color light and the third color light. For example, the first color light is any one of red light, green light, and blue light. For example, one patterning process includes processes such as coating, exposure, development, and etching of photoresist.

[0081] A planarization layer 71 is formed on the hue adjustment layer 7 to planarize the hue adjustment layer 7. For example, the material of the planarization layer 71 is a transparent organic material.

[0082] As Figure 2 As shown, a cholesteric liquid crystal layer 8 and a polarizer 9 are formed on the planarization layer 71. The cholesteric liquid crystal layer 8 and the polarizer 9 cover the pixel definition layer 31, the first color light-emitting element EL1, the second color light-emitting element EL2, and the third color light-emitting element EL3. The transmittance of the cholesteric liquid crystal layer 8 to the first color light is less than the transmittance to the second color light and the third color light.

[0083] At least one embodiment of the present disclosure further provides a display device including the above-mentioned display panel. The display device can be any product or component with a display function such as a mobile phone, a tablet computer, a television, a monitor, a laptop computer, a digital photo frame, a navigator, an in-vehicle display screen, etc., and the embodiments of the present disclosure do not limit this.

[0084] There are also the following points to note:

[0085] (1) The drawings of the embodiments of the present disclosure only relate to the structures involved in the embodiments of the present disclosure, and other structures can refer to the general design.

[0086] (2) For clarity, in the drawings used to describe the embodiments of the present disclosure, the thickness of layers or regions is enlarged or reduced, that is, these drawings are not drawn to actual scale. It can be understood that when an element such as a layer, a film, a region, or a substrate is referred to as being "on" or "under" another element, the element can be "directly" on or under the other element or there can be an intermediate element.

[0087] (3) Without conflict, the embodiments of the present disclosure and the features in the embodiments can be combined with each other to obtain new embodiments.

[0088] As described above, this is only a specific embodiment of the present disclosure. However, the protection scope of the present disclosure is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present disclosure can easily think of changes or substitutions, which should all be covered within the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure shall be subject to the protection scope of the claims.

Claims

1. An OLED display panel, characterized in that: include: Substrate (1); An OLED device layer (3), comprising a first color light-emitting element, a second color light-emitting element and a third color light-emitting element, and located on the display side of the substrate (1); A cholesteric liquid crystal layer (8) is located on a side of the OLED device layer (3) away from the substrate (1), and the cholesteric liquid crystal layer (8) is configured to have a transmittance to the first color light that is lower than the transmittance to the second color light and the third color light; a polarizer (9), located on a side of the cholesteric liquid crystal layer (8) away from the substrate (1); A hue adjustment layer (7) is located on a side of the OLED device layer (3) away from the substrate (1), and the hue adjustment layer (7) is configured to have a transmittance to the first color light greater than the transmittance to the second color light and the third color light.

2. The OLED display panel according to claim 1, characterized in that: The orthographic projections of the first color light-emitting element, the second color light-emitting element and the third color light-emitting element on the substrate (1) do not overlap with the orthographic projection of the hue adjustment layer (7) on the substrate (1).

3. The OLED display panel according to claim 2, characterized in that: The display panel further comprises a black matrix (6), wherein the black matrix (6) is arranged on a side of the first color light-emitting element away from the substrate (1), and an orthographic projection of the black matrix (6) on the substrate (1) surrounds an orthographic projection of the first color light-emitting element on the substrate (1).

4. The OLED display panel according to claim 3, characterized in that: The black matrix (6) is located between the hue adjustment layer (7) and the substrate (1).

5. The OLED display panel according to claim 1, characterized in that: The orthographic projections of at least part of the first color light-emitting elements on the substrate (1) fall within the orthographic projection range of the hue adjustment layer (7) on the substrate (1), and the orthographic projections of the second color light-emitting elements and the third color light-emitting elements on the substrate (1) do not overlap with the orthographic projection of the hue adjustment layer (7) on the substrate (1).

6. The OLED display panel according to claim 1, characterized in that: The hue adjustment layer (7) is located between the OLED device layer (3) and the cholesteric liquid crystal layer (8).

7. The OLED display panel according to claim 6, characterized in that: The display panel further comprises a touch layer (5), wherein the touch layer (5) is located between the cholesteric liquid crystal layer (8) and the substrate (1); The hue adjustment layer (7) is located between the touch control layer (5) and the cholesteric liquid crystal layer (8); or, The hue adjustment layer (7) is located between the touch layer (5) and the substrate (1); or, The hue adjustment layer (7) is located inside the touch control layer (5).

8. The OLED display panel according to claim 1, characterized in that: The display panel further comprises an encapsulation layer (4), the encapsulation layer (4) being located on a side of the OLED device layer (3) away from the substrate (1), and the hue adjustment layer (7) being located on a side of the encapsulation layer (4) away from the substrate (1); and / or, The display panel further comprises a flat layer (71), wherein the flat layer (71) is located on a side of the hue adjustment layer (7) away from the substrate (1).

9. The OLED display panel according to claim 1, characterized in that: The first color light is any one of red light, green light and blue light.

10. A method for preparing an OLED display panel, characterized in that: include: Providing a substrate (1); Forming an OLED device layer (3), the OLED device layer (3) comprising a first color light-emitting element, a second color light-emitting element and a third color light-emitting element located on the display side of the substrate (1); forming a cholesteric liquid crystal layer (8), the cholesteric liquid crystal layer (8) being located on a side of the OLED device layer (3) away from the substrate (1) and being configured to have a transmittance to the first color light that is lower than a transmittance to the second color light and the third color light; forming a polarizing plate (9), wherein the polarizing plate (9) is located on a side of the cholesteric liquid crystal layer (8) away from the substrate (1); A hue adjustment layer (7) is formed. The hue adjustment layer (7) is located on a side of the OLED device layer (3) away from the substrate (1) and is configured to have a transmittance to the first color light greater than the transmittance to the second color light and the third color light.

11. A display device, characterized in that: It comprises the OLED display panel according to any one of claims 1 to 9 or the OLED display panel prepared by the method according to claim 10.

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