Display panel, driving method thereof, and display device

Abstract

A display panel, a driving method thereof, and a display device. The display panel comprises a display area, including a plurality of pixel units located in the display area; the pixel units comprise primary pixels and auxiliary pixels; the aperture area of ​​the primary pixels is larger than the aperture area of ​​the auxiliary pixels; a driving circuit is electrically connected to the pixel units and is used to drive the primary and auxiliary pixels in the pixel units to illuminate; the driving circuit stores a first set of parameters and a second set of parameters, wherein the first set of parameters is used to drive the primary pixels in the pixel units to illuminate and the auxiliary pixels to de-illuminate during the initial stage of displaying a low-brightness image; and the second set of parameters is used to drive both the primary and auxiliary pixels in the pixel units to illuminate during the subsequent stage of displaying a low-brightness image; a low-brightness image is an image with a display brightness of less than 2 nits. This display panel can improve defects such as smearing, temperature drift, greening, and brightening when switching between low-brightness images, thereby optimizing the image quality of low-brightness images.

Description

Technical Field

[0001] The embodiments of the present disclosure belong to the field of display technology, and particularly relate to a display panel, a driving method thereof, and a display device. Background Art

[0002] OLED (Organic Light-Emitting Diode) displays have attracted widespread attention due to their advantages such as self-luminescence, low power consumption, lightness, flexibility, brilliant colors, high contrast, and fast response rate. Summary of the Invention

[0003] In a first aspect, an embodiment of the present disclosure provides a display panel having a display area, wherein the display panel includes a plurality of pixel units located in the display area;

[0004] The pixel unit includes a main pixel and an auxiliary pixel; the opening area of ​​the main pixel is larger than the opening area of ​​the auxiliary pixel;

[0005] a driving circuit, electrically connected to the pixel unit, and configured to drive the primary pixel and the auxiliary pixel in the pixel unit to light up;

[0006] The driving circuit stores a first set of parameters and a second set of parameters.

[0007] The first set of parameters is used to drive the main pixel in the pixel unit to light up and the auxiliary pixel to not light up in the initial stage of low-brightness image display;

[0008] The second set of parameters is used to drive the primary pixel and the auxiliary pixel in the pixel unit to light up in a subsequent stage of displaying the low-brightness image;

[0009] The low brightness image is an image with a display brightness below 2 nit.

[0010] In some embodiments, a substrate and a pixel defining layer are further included.

[0011] The pixel defining layer is located on one side of the substrate, and a plurality of first openings and a plurality of second openings are formed in the pixel defining layer;

[0012] The main pixel includes a first sub-pixel, a second sub-pixel and a third sub-pixel of different colors;

[0013] The first sub-pixel, the second sub-pixel, and the third sub-pixel are respectively located in different first openings;

[0014] The auxiliary pixel includes a first auxiliary sub-pixel, a second auxiliary sub-pixel and a third auxiliary sub-pixel of different colors;

[0015] The first auxiliary sub-pixel, the second auxiliary sub-pixel, and the third auxiliary sub-pixel are respectively located in different second openings;

[0016] The first sub-pixel and the first auxiliary sub-pixel have the same color;

[0017] The second sub-pixel and the second auxiliary sub-pixel have the same color;

[0018] The third sub-pixel and the third auxiliary sub-pixel have the same color.

[0019] In some embodiments, the opening area of ​​the first sub-pixel is larger than the opening area of ​​the first auxiliary sub-pixel;

[0020] The opening area of ​​the second sub-pixel is larger than the opening area of ​​the second auxiliary sub-pixel;

[0021] An opening area of ​​the third sub-pixel is larger than an opening area of ​​the third auxiliary sub-pixel.

[0022] In some embodiments, the primary pixel includes a first electrode, a first light-emitting layer, and a second electrode, wherein the first electrode, the first light-emitting layer, and the second electrode are sequentially stacked in a direction away from the substrate, and their orthographic projections on the substrate at least partially overlap;

[0023] The auxiliary pixel comprises a third electrode, a second light-emitting layer, and a fourth electrode, wherein the third electrode, the second light-emitting layer, and the fourth electrode are sequentially stacked in a direction away from the substrate, and their orthographic projections on the substrate at least partially overlap;

[0024] The first light-emitting layer and the second light-emitting layer can emit light of the same wavelength.

[0025] In some embodiments, the total aperture ratio of the main pixel and the auxiliary pixel in the pixel unit is greater than 15%.

[0026] In some embodiments, an opening ratio of the first subpixel, the second subpixel, and the third subpixel in the main pixel is the same as an opening ratio of the first auxiliary subpixel, the second auxiliary subpixel, and the third auxiliary subpixel in the auxiliary pixel.

[0027] In some embodiments, the first sub-pixel is red, the second sub-pixel is green, and the third sub-pixel is blue;

[0028] The aperture ratio of the first sub-pixel, the second sub-pixel and the third sub-pixel in the main pixel is 1:N:M;

[0029] Among them, the value range of N is 1.1~2.0; the value range of M is 1.8~3.0;

[0030] Alternatively, the value range of N is 1.2 to 1.5; the value range of M is 2.0 to 2.6.

[0031] In some embodiments, the orthographic projection shape of the primary pixel on the substrate includes any one of a triangle, a rectangle, a circle, an ellipse, a polygon, and a regular polygon;

[0032] The orthographic projection shape of the auxiliary pixel on the substrate includes any one of a triangle, a rectangle, a circle, an ellipse, a polygon and a regular polygon.

[0033] In some embodiments, the materials of the first light-emitting layer and the second light-emitting layer include organic light-emitting materials;

[0034] Alternatively, the materials of the first light-emitting layer and the second light-emitting layer include quantum dots and organic light-emitting materials.

[0035] In some embodiments, the first set of parameters and the second set of parameters are both Gamma 2.2 curves.

[0036] An embodiment of the present disclosure further provides a display device, which includes the above-mentioned display panel.

[0037] An embodiment of the present disclosure further provides a method for driving a display panel, wherein the display panel includes a plurality of pixel units located in a display area;

[0038] The pixel unit includes a main pixel and an auxiliary pixel; the opening area of ​​the main pixel is larger than the opening area of ​​the auxiliary pixel;

[0039] a driving circuit, electrically connected to the pixel unit, and configured to drive the primary pixel and the auxiliary pixel in the pixel unit to light up;

[0040] The driving method comprises: burning a first set of parameters and a second set of parameters in the driving circuit;

[0041] When the display panel displays a low-brightness image, in an initial stage, the first set of parameters drives the primary pixel in the pixel unit to light up, and the auxiliary pixel to not light up;

[0042] In a subsequent stage, the second set of parameters drives both the primary pixel and the auxiliary pixel in the pixel unit to light up;

[0043] The low brightness image is an image with a display brightness below 2 nit.

[0044] In some embodiments, when the display panel displays a low-brightness image at room temperature, in an initial stage, the first set of parameters drives the primary pixel in the pixel unit to light up, and the auxiliary pixel to not light up;

[0045] In a subsequent stage, the second set of parameters drives both the primary pixel and the auxiliary pixel in the pixel unit to light up;

[0046] When the display panel displays a low-brightness image at high and low temperatures, the first set of parameters drives the main pixel in the pixel unit to light up, and the auxiliary pixel to not light up.

[0047] In some embodiments, the initial stage is the first 1 to 5 frames of images when the low-brightness image starts to be displayed;

[0048] The subsequent stage is other frame images when the low-brightness image is displayed.

[0049] In some embodiments, the normal temperature range is 0°C to 35°C;

[0050] The temperature range of the high temperature is greater than 35°C;

[0051] The low temperature range is less than 0°C.

[0052] The display panel and driving method provided by the embodiments of the present disclosure drive the main pixels in the pixel unit to light up and the auxiliary pixels to not light up in the initial stage of low-brightness image display by using the first set of parameters; and drive both the main pixels and the auxiliary pixels in the pixel unit to light up in the subsequent stage of low-brightness image display by using the second set of parameters; it is possible to reduce the capacitance of the pixels in the pixel unit in the initial stage of low-brightness image display, increase the brightness of the first frame of pixel lighting, improve defects such as ghosting, temperature drift, greening and start-up when switching between low-brightness images, and optimize the image quality of low-brightness images; at the same time, ensure that the display optical performance (such as color deviation, lifespan, efficiency, reliability, etc.) of the display panel does not change in normal brightness mode (i.e., a mode with a display brightness of approximately 350-800 nit).

[0053] The display device provided in the embodiment of the present disclosure improves defects such as ghosting, temperature drift, greening, and brightening when the display device switches to display low-brightness images by adopting the above-mentioned display panel, thereby optimizing the image quality of low-brightness images; at the same time, it ensures that the display optical performance of the display device does not change in normal brightness mode. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] The accompanying drawings are used to provide a further understanding of the embodiments of the present disclosure and constitute a part of the specification. Together with the embodiments of the present disclosure, they are used to explain the present disclosure and do not constitute a limitation of the present disclosure. The above and other features and advantages will become more apparent to those skilled in the art by describing the detailed exemplary embodiments with reference to the accompanying drawings, in which:

[0055] Figure 1a A schematic diagram of the distribution of pixel units in a display panel provided in an embodiment of the present disclosure.

[0056] Figure 1b For the Figure 1a Schematic diagram of the structural section along the AA' section line.

[0057] Figure 2a This is a low grayscale smear curve of a display panel designed with only main pixels in the related art pixel unit.

[0058] Figure 2b is a low grayscale smear curve of the display panel in the embodiment of the present disclosure.

[0059] Figure 2c Graph showing color shift trajectories of the display panel in this embodiment and the display panel in related art in normal brightness mode.

[0060] Figure 3a This is a diagram showing the temperature drift results of a display panel designed with only main pixels in the related art pixel unit.

[0061] Figure 3b Graph showing the temperature drift results of the display panel in an embodiment of the present disclosure.

[0062] Figure 4 The lifespan curve of the display panel in the embodiment of the present disclosure and the display panel in the related art at a brightness of 500 nit. DETAILED DESCRIPTION

[0063] To enable those skilled in the art to better understand the technical solutions of the embodiments of the present disclosure, a display panel, a driving method thereof, and a display device provided by the embodiments of the present disclosure are further described in detail below with reference to the accompanying drawings and specific implementation plans.

[0064] The embodiments of the present disclosure will be described more fully below with reference to the accompanying drawings, but the illustrated embodiments may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully enable those skilled in the art to understand the scope of this disclosure.

[0065] The embodiments of the present disclosure are not limited to the embodiments shown in the drawings, but include modifications of the configurations formed based on the manufacturing process. Therefore, the regions illustrated in the drawings are schematic in nature, and the shapes of the regions shown in the drawings illustrate specific shapes of the regions, but are not intended to be limiting.

[0066] With the development of OLED display technology and the actual application scenarios of products, people's requirements for low-grayscale display of mobile products are becoming increasingly stringent. The display defects that occur in low-grayscale display (i.e. low-brightness display, such as display brightness below 2nit) mainly include smear, temperature drift (chromaticity drift with temperature changes), green tinting, and brightening (the brightness of monochrome sub-pixels is low at low grayscale, resulting in the color of the low-brightness display screen being different from the standard color of the screen).

[0067] In addition to being related to thin-film transistor (TFT) pixel circuits and voltage settings, low-grayscale display is also closely related to light-emitting devices. Reducing the capacitance of the light-emitting device can make the charging speed of the light-emitting device capacitance faster, achieve faster lighting, and improve the smearing and poor lighting during low-grayscale display. In addition, the reason for the temperature drift phenomenon is that on the one hand, the capacitance of the monochrome light-emitting device changes at high or low temperatures and the change trend is inconsistent, causing the white display screen to change from white to other colors; on the other hand, the thin-film transistor (TFT) pixel circuit repeatedly resets the anode of the light-emitting device, causing the temperature of the light-emitting device to change. The current that lights up the light-emitting device is more sensitive to temperature changes, causing the color of the display screen to change.

[0068] In summary, the size of the light-emitting device capacitance has a significant impact on the low-grayscale display of OLED display products. Optimizing the image quality of low-grayscale images of OLED display products by controlling the capacitance of the light-emitting device is a current research direction.

[0069] In order to solve the problems in the related art, in a first aspect, an embodiment of the present disclosure provides a display panel, referring to Figure 1a , wherein the display panel has a display area 100, and the display panel includes a plurality of pixel units 1, which are located in the display area 100; the pixel unit 1 includes a main pixel 11 and an auxiliary pixel 12; the opening area of ​​the main pixel 11 is larger than the opening area of ​​the auxiliary pixel 12; the driving circuit (not shown in the figure) is electrically connected to the pixel unit 1, and is used to drive the main pixel 11 and the auxiliary pixel 12 in the pixel unit 1 to light up; the driving circuit stores a first set of parameters and a second set of parameters, the first set of parameters is used to drive the main pixel 11 in the pixel unit 1 to light up and the auxiliary pixel 12 to not light up in the initial stage of low-brightness picture display; the second set of parameters is used to drive the main pixel 11 and the auxiliary pixel 12 in the pixel unit 1 to light up in the subsequent stage of low-brightness picture display; the low-brightness picture is a picture with a display brightness below 2nit.

[0070] Among them, in the related art, only main pixels are provided in the pixel unit, and no auxiliary pixels are provided. The total aperture ratio and total aperture ratio of the main pixel 11 and the auxiliary pixel 12 in the pixel unit 1 of this embodiment are the same as the aperture ratio and aperture ratio of the main pixel in the pixel unit of the related art. In this embodiment, the main pixel 11 and the auxiliary pixel 12 both adopt organic electroluminescent devices (OLEDs) or quantum dot organic electroluminescent devices (QD-OLEDs). The capacitance C of the light-emitting device is C=εS / 4πkd, where ε is the dielectric constant of the medium, S is the facing area of ​​the capacitor plates (such as the anode and cathode of the light-emitting device), and d is the distance between the plates.

[0071] Compared with the design of only a main pixel in the pixel unit in the related art, when the total aperture ratio and total aperture ratio of the main pixel 11 and the auxiliary pixel 12 in the pixel unit 1 of this embodiment are the same as the aperture ratio and aperture ratio of the main pixel in the pixel unit of the related art, in this embodiment, by making the first set of parameters drive the main pixel 11 in the pixel unit 1 to light up and the auxiliary pixel 12 not to light up in the initial stage of low-brightness image display; and the second set of parameters drive the main pixel 11 and the auxiliary pixel 12 in the pixel unit 1 to light up in the subsequent stage of low-brightness image display; it is possible to reduce the capacitance of the pixel in the pixel unit 1 in the initial stage of low-brightness image display, increase the brightness of the first frame of pixel lighting, improve the defects such as ghosting, temperature drift, greening and starting when switching low-brightness images, and optimize the image quality of low-brightness images; at the same time, ensure that the display optical performance (such as color deviation, life, efficiency, reliability, etc.) of the display panel in normal brightness mode (i.e., a mode with a display brightness of approximately 350-800nit) does not change.

[0072] In some embodiments, both the first and second sets of parameters are Gamma 2.2 curves. That is, both the first and second sets of parameters refer to curves that relate different grayscale levels to brightness. A Gamma 2.2 curve is used to describe the brightness response characteristics of a display, with an exponent of 2.2. The Gamma value characterizes the brightness response characteristics of a display, and a Gamma value of 2.2 closely matches the visual characteristics of the human eye. The Gamma 2.2 curve exhibits a nonlinear relationship between display brightness and input signal.

[0073] In some embodiments, reference Figure 1a and Figure 1bThe display panel also includes a substrate 2 and a pixel defining layer 3, the pixel defining layer 3 is located on one side of the substrate 2, and a plurality of first openings 31 and a plurality of second openings 32 are opened in the pixel defining layer 3; the main pixel 11 includes a first sub-pixel 111, a second sub-pixel 112 and a third sub-pixel 113 of different colors; the first sub-pixel 111, the second sub-pixel 112 and the third sub-pixel 113 are respectively located in different first openings 31; the auxiliary pixel 12 includes a first auxiliary sub-pixel 121, a second auxiliary sub-pixel 122 and a third auxiliary sub-pixel 123 of different colors; the first auxiliary sub-pixel 121, the second auxiliary sub-pixel 122 and the third auxiliary sub-pixel 123 are respectively located in different second openings 32; the first sub-pixel 111 and the first auxiliary pixel 121 have the same color; the second sub-pixel 112 and the second auxiliary pixel 122 have the same color; the third sub-pixel 113 and the third auxiliary pixel 123 have the same color.

[0074] In some embodiments, reference Figure 1a , the number of second sub-pixels 112 is twice the number of first sub-pixels 111; the number of second sub-pixels 112 is twice the number of third sub-pixels 113; the number of second auxiliary sub-pixels 122 is twice the number of first auxiliary sub-pixels 121; the number of second auxiliary sub-pixels 122 is twice the number of third auxiliary sub-pixels 123; the first sub-pixels 111, the second sub-pixels 112 and the third sub-pixels 113 are arranged in an array; the first auxiliary sub-pixels 121, the second auxiliary sub-pixels 122 and the third auxiliary sub-pixels 123 are arranged in an array; the first auxiliary sub-pixels 121, the second auxiliary sub-pixels 122 and the third auxiliary sub-pixels 123 surround one second sub-pixel 112.

[0075] It should be noted that there is no limitation on the number and distribution of the first sub-pixel 111, the second sub-pixel 112 and the third sub-pixel 113 in the pixel unit 1, and they can be any number and any distribution; there is no limitation on the number and distribution of the first auxiliary sub-pixel 121, the second auxiliary sub-pixel 122 and the third auxiliary sub-pixel 123 in the pixel unit 1, and they can be any number and any distribution.

[0076] In some embodiments, reference Figure 1a The pixel unit 1 includes a first sub-pixel 111 , two second sub-pixels 112 , a third sub-pixel 113 , a first auxiliary sub-pixel 121 , two second auxiliary sub-pixels 122 and a third auxiliary sub-pixel 123 .

[0077] In some embodiments, reference Figure 1aThe opening area of ​​the first sub-pixel 111 is larger than the opening area of ​​the first auxiliary sub-pixel 121; the opening area of ​​the second sub-pixel 112 is larger than the opening area of ​​the second auxiliary sub-pixel 122; and the opening area of ​​the third sub-pixel 113 is larger than the opening area of ​​the third auxiliary sub-pixel 123. With this arrangement, the first set of parameters can be used to drive the primary pixel 11 in the pixel unit 1 to illuminate and the auxiliary pixel 12 to de-illuminate during the initial stage of low-brightness image display. This reduces the capacitance of the pixel during the initial stage of low-brightness image display, thereby improving the image quality of the low-brightness image while ensuring that the display optical performance (such as color shift, lifespan, efficiency, reliability, etc.) of the display panel in normal brightness mode (display brightness of approximately 350-800 nits) remains unchanged.

[0078] In some embodiments, reference Figure 1b The main pixel 11 includes a first electrode 11A, a first light-emitting layer 11B, and a second electrode 11C. The first electrode 11A, the first light-emitting layer 11B, and the second electrode 11C are sequentially stacked in a direction away from the substrate 2, and their orthographic projections on the substrate 2 at least partially overlap. The auxiliary pixel 12 includes a third electrode 12A, a second light-emitting layer 12B, and a fourth electrode 12C. The third electrode 12A, the second light-emitting layer 12B, and the fourth electrode 12C are sequentially stacked in a direction away from the substrate 2, and their orthographic projections on the substrate 2 at least partially overlap. The first light-emitting layer 11B and the second light-emitting layer 12B can emit light of the same wavelength.

[0079] In some embodiments, the first light-emitting layer 11B and the second light-emitting layer 12B may be made of the same material or different materials.

[0080] In some embodiments, the materials of the first light-emitting layer 11B and the second light-emitting layer 12B include organic light-emitting materials; or, the materials of the first light-emitting layer 11B and the second light-emitting layer 12B include quantum dots and organic light-emitting materials.

[0081] In some embodiments, the main pixel 11 and the auxiliary pixel 12 have the same structure, and both the main pixel 11 and the auxiliary pixel 12 have a structure of a single light-emitting functional layer, or both the main pixel 11 and the auxiliary pixel 12 have a stacked structure of multiple light-emitting functional layers, that is, a light-emitting device with a stacked structure.

[0082] In some embodiments, the first electrode 11A and the third electrode 12A are independently provided, and the second electrode 11C and the fourth electrode 12C can be independently provided or can be an integrated structure.

[0083] In some embodiments, the total aperture ratio of the primary pixel 11 and the auxiliary pixel 12 in the pixel unit 1 is greater than 15%.

[0084] In this embodiment, the structures of the primary pixel 11 and the auxiliary pixel 12 are identical to those of the primary pixel in the related art pixel unit. The total aperture ratio and total aperture ratio of the primary pixel 11 and the auxiliary pixel 12 are identical to those of the primary pixel in the related art pixel unit. This arrangement facilitates improving poor image quality of the display panel when displaying low-brightness images by setting the first and second sets of parameters in the driver circuit.

[0085] In some embodiments, the opening ratios of the first, second, and third subpixels 111, 112, and 113 in the main pixel 11 are the same as the opening ratios of the first, second, and third auxiliary subpixels 121, 122, and 123 in the auxiliary pixel 12.

[0086] In some embodiments, the opening ratios of the first subpixel 111 , the second subpixel 112 , and the third subpixel 113 in the main pixel 11 may be different from the opening ratios of the first auxiliary subpixel 121 , the second auxiliary subpixel 122 , and the third auxiliary subpixel 123 in the auxiliary pixel 12 .

[0087] In some embodiments, the first sub-pixel 111 is red, the second sub-pixel 112 is green, and the third sub-pixel 113 is blue; the opening ratio of the first sub-pixel 111, the second sub-pixel 112, and the third sub-pixel 113 in the main pixel 11 is 1:N:M; wherein the value range of N is 1.1 to 2.0; the value range of M is 1.8 to 3.0; or, the value range of N is 1.2 to 1.5; the value range of M is 2.0 to 2.6.

[0088] In some embodiments, the opening ratio of the first sub-pixel 111, the second sub-pixel 112 and the third sub-pixel 113 in the main pixel 11 is 1:1.4:2.2; the opening ratio of the first auxiliary sub-pixel 121, the second auxiliary sub-pixel 122 and the third auxiliary sub-pixel 123 in the auxiliary pixel 12 is 1:1.4:2.2; the opening rate of the first sub-pixel 111 in the main pixel 11 is 4%-6%, the opening rate of the second sub-pixel 112 is 7%-10%, and the opening rate of the third sub-pixel 113 is 11%-15%; the opening rate of the first auxiliary sub-pixel 121 in the auxiliary pixel 12 is 1%-1.25%, the opening rate of the second auxiliary sub-pixel 122 is 1.5%-2%, and the opening rate of the third auxiliary sub-pixel 123 is 3%-5%.

[0089] In some embodiments, the aperture ratios of the first subpixel 111, the second subpixel 112, and the third subpixel 113 in the primary pixel 11 are 5%, 7%, and 12%, respectively; the aperture ratios of the first auxiliary subpixel 121, the second auxiliary subpixel 122, and the third auxiliary subpixel 123 in the auxiliary pixel 12 are 1.25%, 1.75%, and 3%, respectively; and the total aperture ratio of the primary pixel 11 and the auxiliary pixel 12 in the pixel unit 1 is 30%. Correspondingly, in related art, the aperture ratio of the red pixel in the pixel unit is 6.25%, the aperture ratio of the green pixel is 8.75%, and the aperture ratio of the blue pixel is 15%. The total aperture ratio of the different color pixels in the pixel unit is also 30%.

[0090] In some embodiments, the orthographic projection shape of the main pixel 11 on the substrate 2 includes any one of a triangle, a rectangle, a circle, an ellipse, a polygon and a regular polygon; the orthographic projection shape of the auxiliary pixel 12 on the substrate 2 includes any one of a triangle, a rectangle, a circle, an ellipse, a polygon and a regular polygon.

[0091] Based on the display panel in the above embodiment, the embodiment of the present disclosure also provides a driving method for the display panel, wherein the display panel includes multiple pixel units located in the display area; the pixel unit includes a main pixel and an auxiliary pixel; the opening area of ​​the main pixel is larger than the opening area of ​​the auxiliary pixel; the driving circuit is electrically connected to the pixel unit, and is used to drive the main pixel and the auxiliary pixel in the pixel unit to light up; the driving method includes: burning a first set of parameters and a second set of parameters in the driving circuit; when the display panel displays a low-brightness picture, in the initial stage, the first set of parameters drives the main pixel in the pixel unit to light up, and the auxiliary pixel is not lit; in the subsequent stage, the second set of parameters drives both the main pixel and the auxiliary pixel in the pixel unit to light up; the low-brightness picture is a picture with a display brightness below 2nit.

[0092] In the related art, only a primary pixel is provided in the pixel unit, and no auxiliary pixel is provided. The total aperture ratio and total aperture ratio of the primary and auxiliary pixels in the pixel unit of this embodiment are the same as the aperture ratio and aperture ratio of the primary pixel in the pixel unit of the related art. In this embodiment, in the initial stage, the first set of parameters drives the primary pixel in the pixel unit to light up, and the auxiliary pixel to not light up. According to the capacitance formula C = εS / 4πkd of the light-emitting device, it can be seen that due to the reduction in the area of ​​the red, green, and blue pixels in the pixel unit, the capacitance of the red, green, and blue pixels is reduced by 20% respectively.

[0093] In this embodiment, by making the first set of parameters drive the main pixels in the pixel unit to light up and the auxiliary pixels not to light up in the initial stage of low-brightness image display; the second set of parameters drive the main pixels and auxiliary pixels in the pixel unit to light up in the subsequent stage of low-brightness image display; it is possible to reduce the capacitance of the pixels in the pixel unit in the initial stage of low-brightness image display, increase the brightness of the first frame of pixel lighting, improve the defects such as ghosting, temperature drift, greening and starting when switching the low-brightness image, and optimize the image quality of the low-brightness image; at the same time, ensure that the display optical performance (such as color deviation, life, efficiency, reliability, etc.) of the display panel in normal brightness mode (i.e., the mode with display brightness of approximately 350-800nit) does not change.

[0094] In some embodiments, the initial stage is the first 1 to 5 frames when the low-brightness image starts to be displayed; the subsequent stage is the other frames when the low-brightness image is displayed.

[0095] In this embodiment, refer to Figure 2a , is the low grayscale smear curve of the display panel designed with only main pixels in the related art pixel unit, Figure 2b This is the low grayscale smear curve of the display panel in the embodiment of the present disclosure. By comparison, it can be seen that the coverage area of ​​the low grayscale smear curve in the initial stage of low brightness picture display, such as the initial three peaks, is significantly larger than the coverage area of ​​the initial three peaks of the low grayscale smear curve in the related art. The measured results show that the smear WFFR (i.e., the ratio of the brightness of the first frame of the low brightness picture to the average brightness of the first 5 frames) of the low grayscale smear curve of the display panel in the present embodiment is increased by 27.9% compared with the smear WFFR (i.e., the ratio of the brightness of the first frame of the low brightness picture to the average brightness of the first 5 frames) of the low grayscale smear curve of the display panel in the related art. That is, the pixel design and driving method of the display panel in the present embodiment significantly improve the bad smear that occurs when displaying low brightness pictures. At the same time, referring to Figure 2c There is no difference in the color shift level (color shift level in the CIE1931 color space) between the display panel in this embodiment and the display panel in the related art in normal brightness mode (i.e., a mode in which the display brightness is approximately 350-800 nit), and there is no difference in the lifespan level between the display panel in this embodiment and the display panel in the related art when the pixel aperture ratio is the same, and there is no difference in the white light efficiency between the two under the same brightness and the same chromaticity.

[0096] In some embodiments, when the display panel displays a low-brightness image at room temperature, in the initial stage, the first set of parameters drives the main pixel in the pixel unit to light up, and the auxiliary pixel to not light up; in the subsequent stage, the second set of parameters drives both the main pixel and the auxiliary pixel in the pixel unit to light up; when the display panel displays a low-brightness image at high and low temperatures, the first set of parameters drives the main pixel in the pixel unit to light up, and the auxiliary pixel to not light up.

[0097] In some embodiments, the temperature range of normal temperature is 0°C to 35°C; the temperature range of high temperature is greater than 35°C; and the temperature range of low temperature is less than 0°C.

[0098] By driving the low-brightness image of the display panel in this way, the size of the pixel capacitance in the pixel unit can be adjusted at normal temperature, high temperature and low temperature, thereby not only improving the poor ghosting when switching the low-brightness image, but also improving the poor temperature drift when displaying the low-brightness image at high and low temperatures.

[0099] In this embodiment, refer to Figure 3a , which is a temperature drift result diagram of a display panel designed with only main pixels in the related art pixel unit. Figure 3b The figure is a temperature drift result diagram of the display panel in the embodiment of the present disclosure; by comparison, it can be seen that the low-temperature temperature drift result of the display panel in the embodiment is significantly improved when displaying low-brightness images compared with the related art; Figure 3a As can be seen from the figure, the temperature drift (i.e., chromaticity drift) ΔWy of the low-brightness image of the display panel at low temperature in the related art is 0.2-0.3 (the ΔWy is the difference between Wy at low temperature and Wy at room temperature in the CIE1931 color space); Figure 3b As can be seen from the figure, the temperature drift (i.e., chromaticity drift) ΔWy of the low-brightness image of the display panel in this embodiment at low temperatures is 0-0.04 (ΔWy is the difference between Wy at low temperatures and Wy at room temperature in the CIE1931 color space); compared with the structure and driving scheme of the display panel in this embodiment and the related art, the display effect of the low-brightness image at low temperatures is significantly optimized from green to white or slightly bluish; at the same time, Figure 3a and Figure 3b It can be seen that the temperature drift △Wx (△Wx is the difference between Wx at high temperature and Wx at normal temperature in the CIE1931 color space) and △Wy (△Wy is the difference between Wy at high temperature and Wy at normal temperature in the CIE1931 color space) of the low-brightness image of the display panel at high temperature in this embodiment is also significantly reduced compared with the temperature drift △Wx (△Wx is the difference between Wx at high temperature and Wx at normal temperature in the CIE1931 color space) and △Wy (△Wy is the difference between Wy at high temperature and Wy at normal temperature in the CIE1931 color space) of the low-brightness image of the display panel at high temperature in the related art.

[0100] In this embodiment, the following Table 1 shows the reliability test results of the display panel in the related art and the display panel in this embodiment under different test conditions.

[0101] Table 1

[0102]

[0103] In Table 1, after 240 hours of operation tests such as 8585 (high temperature and high humidity operation test), THO (high temperature and high humidity operation test), LTO (low temperature operation test), HTO (high temperature operation test), etc., there are no optical related defects. After 240 hours of storage tests such as HTS (high temperature storage test), LTS (low temperature storage test), THS (high temperature and high humidity storage test), TST (temperature shock test), UVtesting (light obstruction test), HAST (high voltage accelerated aging test), etc., there are no optical related defects. In addition, refer to Figure 4 Compared with the design of the display panel in the related art, since the total aperture rate and total aperture ratio of the pixels in the display panel of this embodiment are the same as those of the display panel in the related art, the lifespan level of the display panel in this embodiment and the display panel in the related art at the same brightness (such as 500nit brightness) is consistent.

[0104] The driving method of the display panel provided in this embodiment drives the main pixels in the pixel unit to light up and the auxiliary pixels to not light up by using the first set of parameters in the initial stage of low-brightness image display; and drives both the main pixels and the auxiliary pixels in the pixel unit to light up in the subsequent stage of low-brightness image display by using the second set of parameters. This method can reduce the capacitance of the pixels in the pixel unit in the initial stage of low-brightness image display, increase the brightness of the first frame of pixel lighting, improve defects such as ghosting, temperature drift, greening, and start-up when switching between low-brightness images, and optimize the image quality of low-brightness images. At the same time, it ensures that the display optical performance (such as color deviation, lifespan, efficiency, reliability, etc.) of the display panel does not change in normal brightness mode (i.e., a mode with a display brightness of approximately 350-800 nit).

[0105] An embodiment of the present disclosure further provides a display device, comprising the display panel in the above embodiment.

[0106] By adopting the display panel of the above embodiment, defects such as ghosting, temperature drift, greening and brightening when the display device switches to display low-brightness images are improved, and the image quality of low-brightness images is optimized; at the same time, it is ensured that the display optical performance of the display device in normal brightness mode does not change.

[0107] The display device provided in the embodiments of the present disclosure may be any product or component with a display function, such as an OLED panel, a QD-OLED panel, an OLED TV, an OLED billboard, a monitor, a mobile phone, a navigator, or the like.

[0108] It is understood that the above embodiments are merely exemplary embodiments for illustrating the principles of the present disclosure, and the present disclosure is not limited thereto. Those skilled in the art may make various modifications and improvements without departing from the spirit and substance of the present disclosure, and such modifications and improvements are also considered to be within the scope of protection of the present disclosure.

Claims

1. A display panel having a display area, wherein: comprising a plurality of pixel units, located in the display area; The pixel unit includes a main pixel and an auxiliary pixel; the opening area of ​​the main pixel is larger than the opening area of ​​the auxiliary pixel; a driving circuit, electrically connected to the pixel unit, and configured to drive the primary pixel and the auxiliary pixel in the pixel unit to light up; The driving circuit stores a first set of parameters and a second set of parameters. The first set of parameters is used to drive the main pixel in the pixel unit to light up and the auxiliary pixel to not light up in the initial stage of low-brightness image display; The second set of parameters is used to drive the primary pixel and the auxiliary pixel in the pixel unit to light up in a subsequent stage of displaying the low-brightness image; The low brightness image is an image with a display brightness below 2 nit.

2. The display panel according to claim 1, wherein Also includes a substrate and a pixel definition layer, The pixel defining layer is located on one side of the substrate, and a plurality of first openings and a plurality of second openings are formed in the pixel defining layer; The main pixel includes a first sub-pixel, a second sub-pixel and a third sub-pixel of different colors; The first sub-pixel, the second sub-pixel, and the third sub-pixel are respectively located in different first openings; The auxiliary pixel includes a first auxiliary sub-pixel, a second auxiliary sub-pixel and a third auxiliary sub-pixel of different colors; The first auxiliary sub-pixel, the second auxiliary sub-pixel, and the third auxiliary sub-pixel are respectively located in different second openings; The first sub-pixel and the first auxiliary sub-pixel have the same color; The second sub-pixel and the second auxiliary sub-pixel have the same color; The third sub-pixel and the third auxiliary sub-pixel have the same color.

3. The display panel according to claim 2, wherein: The opening area of ​​the first sub-pixel is larger than the opening area of ​​the first auxiliary sub-pixel; The opening area of ​​the second sub-pixel is larger than the opening area of ​​the second auxiliary sub-pixel; An opening area of ​​the third sub-pixel is larger than an opening area of ​​the third auxiliary sub-pixel.

4. The display panel according to claim 2, wherein: The primary pixel comprises a first electrode, a first light-emitting layer, and a second electrode, wherein the first electrode, the first light-emitting layer, and the second electrode are sequentially stacked in a direction away from the substrate, and their orthographic projections on the substrate at least partially overlap; The auxiliary pixel comprises a third electrode, a second light-emitting layer, and a fourth electrode, wherein the third electrode, the second light-emitting layer, and the fourth electrode are sequentially stacked in a direction away from the substrate, and their orthographic projections on the substrate at least partially overlap; The first light-emitting layer and the second light-emitting layer can emit light of the same wavelength.

5. The display panel according to claim 1, wherein: The total aperture ratio of the main pixel and the auxiliary pixel in the pixel unit is greater than 15%. The display panel according to claim 2 , wherein: The aperture ratio of the first subpixel, the second subpixel, and the third subpixel in the main pixel is the same as the aperture ratio of the first auxiliary subpixel, the second auxiliary subpixel, and the third auxiliary subpixel in the auxiliary pixel.

7. The display panel according to claim 6, wherein: The first sub-pixel is red, the second sub-pixel is green, and the third sub-pixel is blue; The aperture ratio of the first sub-pixel, the second sub-pixel and the third sub-pixel in the main pixel is 1:N:M; Among them, the value range of N is 1.1~2.0; the value range of M is 1.8~3.0; Alternatively, the value range of N is 1.2 to 1.5; the value range of M is 2.0 to 2.

6.

8. The display panel according to claim 2, wherein: The orthographic projection shape of the main pixel on the substrate includes any one of a triangle, a rectangle, a circle, an ellipse, a polygon and a regular polygon; The orthographic projection shape of the auxiliary pixel on the substrate includes any one of a triangle, a rectangle, a circle, an ellipse, a polygon and a regular polygon.

9. The display panel according to claim 4, wherein: The materials of the first light-emitting layer and the second light-emitting layer include organic light-emitting materials; Alternatively, the materials of the first light-emitting layer and the second light-emitting layer include quantum dots and organic light-emitting materials.

10. The display panel according to claim 1, wherein The first set of parameters and the second set of parameters are both Gamma 2.2 curves.

11. A display device, wherein: The display panel comprises the display panel according to any one of claims 1 to 10.

12. A method for driving a display panel, wherein: The display panel includes a plurality of pixel units located in a display area; The pixel unit includes a main pixel and an auxiliary pixel; the opening area of ​​the main pixel is larger than the opening area of ​​the auxiliary pixel; a driving circuit, electrically connected to the pixel unit, and configured to drive the primary pixel and the auxiliary pixel in the pixel unit to light up; The driving method comprises: burning a first set of parameters and a second set of parameters in the driving circuit; When the display panel displays a low-brightness image, in an initial stage, the first set of parameters drives the primary pixel in the pixel unit to light up, and the auxiliary pixel to not light up; In a subsequent stage, the second set of parameters drives both the primary pixel and the auxiliary pixel in the pixel unit to light up; The low brightness image is an image with a display brightness below 2 nit.

13. The method for driving a display panel according to claim 12, wherein: When the display panel displays a low-brightness image at room temperature, in an initial stage, the first set of parameters drives the primary pixel in the pixel unit to light up, and the auxiliary pixel to not light up; In a subsequent stage, the second set of parameters drives both the primary pixel and the auxiliary pixel in the pixel unit to light up; When the display panel displays a low-brightness image at high and low temperatures, the first set of parameters drives the main pixel in the pixel unit to light up, and the auxiliary pixel to not light up.

14. The method for driving a display panel according to claim 13, wherein: The initial stage is the first 1 to 5 frames of images when the low-brightness image starts to be displayed; The subsequent stage is other frame images when the low-brightness image is displayed.

15. The method for driving a display panel according to claim 13, wherein: The temperature range of the normal temperature is 0°C to 35°C; The temperature range of the high temperature is greater than 35°C; The low temperature range is less than 0°C.

Images