Display panel and driving method therefor, and display apparatus
By introducing auxiliary pixels into the OLED display panel and adjusting the driving parameters, the problems of ghosting, temperature drift, and brightness activation in low grayscale displays were solved, improving the display effect of low-brightness images while maintaining stable performance in normal brightness mode.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- BOE TECHNOLOGY GROUP CO LTD
- Filing Date
- 2025-12-04
- Publication Date
- 2026-07-09
Smart Images
Figure CN2025140059_09072026_PF_FP_ABST
Abstract
Description
Display panel, driving method thereof, and display device Technical Field
[0001] This disclosure pertains to the field of display technology, specifically relating to a display panel, its driving method, and a display device. Background Technology
[0002] OLED (Organic Light-Emitting Diode) displays have attracted widespread attention due to their advantages such as self-illumination, low power consumption, thinness, flexibility, vibrant colors, high contrast, and fast response speed. Summary of the Invention
[0003] In a first aspect, embodiments of this disclosure provide a display panel having a display area, wherein a plurality of pixel units are located in the display area;
[0004] The pixel unit includes a main pixel and an auxiliary pixel; the aperture area of the main pixel is larger than the aperture area of the auxiliary pixel;
[0005] A driving circuit, electrically connected to the pixel unit, is used to drive the main 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 remain off during the initial stage of low-brightness screen display.
[0008] The second set of parameters is used to drive both the main pixel and the auxiliary pixel in the pixel unit to light up in the subsequent stage of the low-brightness screen display;
[0009] The low-brightness screen refers to a screen with a brightness of less than 2 nits.
[0010] In some embodiments, a substrate and a pixel defining layer are also included.
[0011] The pixel defining layer is located on one side of the substrate, and the pixel defining layer has a plurality of first openings and a plurality of second openings;
[0012] The main pixel includes a first sub-pixel, a second sub-pixel, and a third sub-pixel with different colors;
[0013] The first sub-pixel, the second sub-pixel, and the third sub-pixel are each located in a different first opening;
[0014] The auxiliary pixels include a first auxiliary sub-pixel, a second auxiliary sub-pixel, and a third auxiliary sub-pixel with different colors;
[0015] The first auxiliary sub-pixel, the second auxiliary sub-pixel, and the third auxiliary sub-pixel are each located in a different second opening;
[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] The opening area of the third sub-pixel is larger than the opening area of the third auxiliary sub-pixel.
[0022] In some embodiments, the main 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 stacked sequentially along a direction away from the substrate and their orthogonal projections on the substrate at least partially overlap.
[0023] The auxiliary pixel includes 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 stacked sequentially along a direction away from the substrate and their orthogonal 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 15% or more.
[0026] In some embodiments, the aperture ratio of the first sub-pixel, the second sub-pixel, and the third sub-pixel in the main pixel is the same as the aperture ratio of the first auxiliary sub-pixel, the second auxiliary sub-pixel, and the third auxiliary sub-pixel 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] Where N ranges from 1.1 to 2.0; and M ranges from 1.8 to 3.0.
[0030] Alternatively, N can range from 1.2 to 1.5, and M can range from 2.0 to 2.6.
[0031] In some embodiments, the orthographic projection shape of the main pixel on the substrate includes any one of triangle, rectangle, circle, ellipse, polygon, and regular polygon;
[0032] The orthographic projection shape of the auxiliary pixel on the substrate includes any one of triangle, rectangle, circle, ellipse, polygon, and 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 and second light-emitting layers may include quantum dots and organic light-emitting materials.
[0035] In some embodiments, both the first set of parameters and the second set of parameters are Gamma2.2 curves.
[0036] This disclosure also provides a display device, which includes the above-described display panel.
[0037] This disclosure also provides a driving method for a display panel, wherein the display panel includes a plurality of pixel units located in the display area;
[0038] The pixel unit includes a main pixel and an auxiliary pixel; the aperture area of the main pixel is larger than the aperture area of the auxiliary pixel;
[0039] A driving circuit, electrically connected to the pixel unit, is used to drive the main pixel and the auxiliary pixel in the pixel unit to light up;
[0040] The driving method includes: programming a first set of parameters and a second set of parameters into the driving circuit;
[0041] When the display panel displays a low-brightness image, in the initial stage, the first set of parameters drives the main pixel in the pixel unit to light up, while the auxiliary pixels do not light up.
[0042] In a subsequent stage, the second set of parameters drives both the main pixel and the auxiliary pixel in the pixel unit to light up;
[0043] The low-brightness screen refers to a screen with a brightness of less than 2 nits.
[0044] 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, while the auxiliary pixel does not light up;
[0045] In a subsequent stage, the second set of parameters drives both the main pixel and the auxiliary pixel in the pixel unit to light up;
[0046] When the display panel displays a low-brightness image under high and low temperatures, the first set of parameters drives the main pixel in the pixel unit to light up, while the auxiliary pixels remain off.
[0047] In some embodiments, the initial stage is the first 1 to 5 frames at the start of the low-brightness screen display;
[0048] The subsequent stage refers to other frames displayed during the low-brightness screen display.
[0049] In some embodiments, the ambient 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 its driving method provided in this disclosure, by using a first set of parameters to drive the main pixels in the pixel unit to light up while the auxiliary pixels remain off during the initial stage of low-brightness screen display, and a second set of parameters to drive both the main pixels and auxiliary pixels in the pixel unit to light up during the subsequent stage of low-brightness screen display, can reduce the capacitance of pixels in the pixel unit during the initial stage of low-brightness screen display, increase the brightness of the first frame when the pixels are lit, improve the problems such as ghosting, temperature drift, green tinge, and on-hook during low-brightness screen switching, and optimize the image quality of low-brightness screens. At the same time, it ensures that the display optical performance (such as color shift, lifespan, efficiency, reliability, etc.) of the display panel does not change in normal brightness mode (i.e., display brightness of approximately 350-800 nits).
[0053] The display device provided in this embodiment improves the display device's performance in low-brightness screen switching by adopting the above-described display panel, thus improving issues such as ghosting, temperature drift, green tint, and screen-on defects, and optimizing the image quality of low-brightness screens. At the same time, it ensures that the display optical performance of the display device does not change in normal brightness mode. Attached Figure Description
[0054] The accompanying drawings are provided to further illustrate the embodiments of this disclosure and form part of the specification. They are used together with the embodiments of this disclosure to explain the disclosure and do not constitute a limitation thereof. The above and other features and advantages will become more apparent to those skilled in the art from the detailed description of exemplary embodiments with reference to the accompanying drawings, in which:
[0055] Figure 1a is a schematic diagram of the distribution of pixel units in a display panel according to an embodiment of the present disclosure.
[0056] Figure 1b is a schematic cross-sectional view of the structure along the AA' section line in Figure 1a.
[0057] Figure 2a shows the low grayscale trailing curve of a display panel with only main pixels in the pixel unit of the related technology.
[0058] Figure 2b shows the low grayscale trailing curve of the display panel in an embodiment of this disclosure.
[0059] Figure 2c is a color shift trajectory diagram of the display panel in normal brightness mode in this embodiment and related technologies.
[0060] Figure 3a shows the temperature drift results of a display panel with only the main pixel in the pixel unit of the related technology.
[0061] Figure 3b is a diagram showing the temperature drift results of the display panel in an embodiment of this disclosure.
[0062] Figure 4 shows the lifespan curve of the display panel at 500 nits brightness in the embodiments of this disclosure and related technologies. Detailed Implementation
[0063] To enable those skilled in the art to better understand the technical solutions of the embodiments of this disclosure, the following describes in further detail a display panel, its driving method, and a display device provided in the embodiments of this disclosure, in conjunction with the accompanying drawings and specific implementation methods.
[0064] Embodiments of this disclosure will be described more fully below with reference to the accompanying drawings; however, the embodiments shown may be embodied in different forms and should not be construed as limited to the embodiments set forth in this disclosure. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will enable those skilled in the art to fully understand the scope of this disclosure.
[0065] This disclosure is not limited to the embodiments shown in the accompanying drawings, but includes modifications to the configuration based on the manufacturing process. Therefore, the areas illustrated in the drawings are schematic, and the shapes of the areas shown illustrate specific shapes of the areas, 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 strict. Display defects that occur in low grayscale display (i.e., low brightness display, such as display brightness below 2 nits) mainly include ghosting, temperature drift (color drift with temperature), greening, and on-hook (low brightness of monochrome subpixels at low grayscale, resulting in the color of the low brightness display screen being different from the standard color of the screen).
[0067] Low grayscale displays are closely related to the light-emitting devices (LEDs) in addition to the thin-film transistor (TFT) pixel circuit and voltage settings. Reducing the capacitance of the LEDs allows for faster charging, resulting in quicker startup and improving ghosting and poor startup in low grayscale displays. Furthermore, temperature drift occurs due to two main reasons: firstly, the capacitance of monochromatic LEDs changes at high or low temperatures with inconsistent trends, causing white displays to change to other colors; secondly, the repeated resets of the LED anode by the TFT pixel circuit cause temperature variations in the LEDs, making the current igniting them more sensitive to temperature changes and resulting in color shifts in the displayed image.
[0068] In summary, the capacitance of the light-emitting device has a significant impact on the low grayscale display of OLED products. Optimizing the image quality of low grayscale images in OLED products by controlling the capacitance of the light-emitting device is a current research direction.
[0069] To address the problems in the related technologies, in a first aspect, embodiments of this disclosure provide a display panel, referring to FIG1a, wherein the display panel has a display area 100, and the display panel includes a plurality of pixel units 1 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; a 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 being used to drive the main pixel 11 in the pixel unit 1 to light up and the auxiliary pixel 12 to remain off in the initial stage of displaying a low-brightness image; the second set of parameters being used to drive both the main pixel 11 and the auxiliary pixel 12 in the pixel unit 1 to light up in the subsequent stage of displaying a low-brightness image; the low-brightness image is an image with a display brightness of less than 2 nits.
[0070] In related technologies, pixel units only have main pixels and no auxiliary pixels. In this embodiment, the total aperture ratio and total aperture proportion of the main pixel 11 and auxiliary pixel 12 in pixel unit 1 are the same as those of the main pixel in pixel units of related technologies. In this embodiment, both the main pixel 11 and auxiliary pixel 12 are organic light-emitting devices (OLEDs) or quantum dot organic light-emitting devices (QD-OLEDs). The capacitance of the light-emitting device is C = εS / 4πkd, where ε is the dielectric constant of the medium, S is the 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 to the design in related technologies where only the main pixel exists in the pixel unit, in this embodiment, the total aperture ratio and total aperture proportion of the main pixel 11 and auxiliary pixel 12 in pixel unit 1 are the same as those of the main pixel in the pixel unit of related technologies. In this embodiment, by using the first set of parameters in the initial stage of low-brightness screen display, the main pixel 11 in pixel unit 1 is driven to light up while the auxiliary pixel 12 is not lit up; in the subsequent stage of low-brightness screen display, the second set of parameters drives both the main pixel 11 and the auxiliary pixel 12 in pixel unit 1 to light up. This can reduce the capacitance of the pixels in pixel unit 1 in the initial stage of low-brightness screen display, increase the brightness of the first frame when the pixels are lit up, improve the problems such as ghosting, temperature drift, greening and start-up when switching displays in low-brightness screens, and optimize the image quality of low-brightness screens. At the same time, it ensures that the display optical performance (such as color shift, lifespan, efficiency, reliability, etc.) of the display panel does not change in the normal brightness mode (i.e., the display brightness is about 350-800 nits).
[0072] In some embodiments, both the first set of parameters and the second set of parameters are Gamma 2.2 curves. That is, both the first set of parameters and the second set of parameters refer to the relationship curves between different gray levels and brightness. The Gamma 2.2 curve is a curve used to describe the brightness response characteristics of a display, and its exponent is 2.2. The Gamma value is used to characterize the brightness response characteristics of a display. The response characteristics with a Gamma value of 2.2 are more consistent with the visual characteristics of the human eye. The Gamma 2.2 curve exhibits a non-linear relationship between display brightness and input signal.
[0073] In some embodiments, referring to Figures 1a and 1b, the display panel further 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 provided 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 sub-pixel 121 are the same color. The second sub-pixel 112 and the second auxiliary sub-pixel 122 are the same color. The third sub-pixel 113 and the third auxiliary sub-pixel 123 are the same color.
[0074] In some embodiments, referring to FIG1a, 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, second sub-pixels 112 and third sub-pixels 113 are arranged in an array; the first auxiliary sub-pixels 121, second auxiliary sub-pixels 122 and third auxiliary sub-pixels 123 are arranged in an array; the first auxiliary sub-pixels 121, second auxiliary sub-pixels 122 and third auxiliary sub-pixels 123 surround a second sub-pixel 112.
[0075] It should be noted that there are no restrictions on the number and distribution of the first sub-pixel 111, the second sub-pixel 112, and the third sub-pixel 113 in pixel unit 1; they can be any number and any distribution. Similarly, there are no restrictions 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 pixel unit 1; they can be any number and any distribution.
[0076] In some embodiments, referring to FIG1a, 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, referring to FIG1a, the aperture area of the first sub-pixel 111 is larger than the aperture area of the first auxiliary sub-pixel 121; the aperture area of the second sub-pixel 112 is larger than the aperture area of the second auxiliary sub-pixel 122; and the aperture area of the third sub-pixel 113 is larger than the aperture area of the third auxiliary sub-pixel 123. With this configuration, the main pixel 11 in pixel unit 1 can be driven to light up while the auxiliary pixel 12 remains off during the initial stage of low-brightness screen display using the first set of parameters. This reduces the capacitance of the pixels during the initial stage of low-brightness screen display, thereby improving the image quality of the low-brightness screen. Simultaneously, it ensures that the display optical performance (such as color shift, lifespan, efficiency, reliability, etc.) of the display panel remains unchanged in normal brightness mode (display brightness approximately 350-800 nits).
[0078] In some embodiments, referring to FIG1b, 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 stacked sequentially in a direction away from the substrate 2, and their orthogonal 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 stacked sequentially in a direction away from the substrate 2, and their orthogonal 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 are single light-emitting functional layers, or the main pixel 11 and the auxiliary pixel 12 are stacked structures of multiple light-emitting functional layers, i.e., a stacked light-emitting device.
[0082] In some embodiments, the first electrode 11A and the third electrode 12A are respectively independently provided, and the second electrode 11C and the fourth electrode 12C can be respectively independently provided, or they can be an integral structure.
[0083] In some embodiments, the total aperture ratio of the main pixel 11 and the auxiliary pixel 12 in pixel unit 1 is 15% or more.
[0084] In this embodiment, the structures of the main pixel 11 and the auxiliary pixel 12 are the same as those of the main pixel in the pixel unit of the related technology. The total aperture ratio and total aperture proportion of the main pixel 11 and the auxiliary pixel 12 are the same as those of the main pixel in the pixel unit of the related technology. This configuration facilitates the improvement of poor image quality of the display panel when displaying low-brightness images by setting the first set of parameters and the second set of parameters in the driving circuit.
[0085] In some embodiments, the aperture ratio of the first sub-pixel 111, the second sub-pixel 112, and the third sub-pixel 113 in the main pixel 11 is the same as the aperture 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.
[0086] In some embodiments, the aperture ratio of the first sub-pixel 111, the second sub-pixel 112, and the third sub-pixel 113 in the main pixel 11 may be different from the aperture 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.
[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 aperture 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 of N ranges from 1.1 to 2.0; the value of M ranges from 1.8 to 3.0; or, the value of N ranges from 1.2 to 1.5; the value of M ranges from 2.0 to 2.6.
[0088] In some embodiments, the aperture 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 aperture 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 aperture ratio of the first sub-pixel 111 in the main pixel 11 is 4%-6%, the aperture ratio of the second sub-pixel 112 is 7%-10%, and the aperture ratio of the third sub-pixel 113 is 11%-15%; the aperture ratio of the first auxiliary sub-pixel 121 in the auxiliary pixel 12 is 1%-1.25%, the aperture ratio of the second auxiliary sub-pixel 122 is 1.5%-2%, and the aperture ratio of the third auxiliary sub-pixel 123 is 3%-5%.
[0089] In some embodiments, the aperture ratios of the first sub-pixel 111, the second sub-pixel 112, and the third sub-pixel 113 in the main pixel 11 are 5%, 7%, and 12%, respectively; the aperture ratios 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 are 1.25%, 1.75%, and 3%, respectively; the total aperture ratio of the main pixel 11 and the auxiliary pixel 12 in the pixel unit 1 is 30%. Correspondingly, in related technologies, 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 pixels of different colors 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 triangle, rectangle, circle, ellipse, polygon, and regular polygon; the orthographic projection shape of the auxiliary pixel 12 on the substrate 2 includes any one of triangle, rectangle, circle, ellipse, polygon, and regular polygon.
[0091] Based on the display panel in the above embodiments, this disclosure also provides a driving method for the display panel. The display panel includes multiple pixel units located in the display area; each 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 is electrically connected to the pixel unit and is used to drive the main pixel and auxiliary pixel in the pixel unit to light up; the driving method includes: programming a first set of parameters and a second set of parameters into the driving circuit; when the display panel displays a low-brightness image, in the initial stage, the first set of parameters drives the main pixel in the pixel unit to light up, while the auxiliary pixel does 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; the low-brightness image is an image with a brightness of less than 2 nits.
[0092] In related technologies, pixel units only have main pixels and no auxiliary pixels. In this embodiment, the total aperture ratio and total aperture proportion of the main and auxiliary pixels in the pixel unit are the same as those of the main pixels in the pixel units of related technologies. In this embodiment, in the initial stage, the first set of parameters drives the main pixels in the pixel unit to light up, while the auxiliary pixels remain off. According to the capacitance formula for light-emitting devices, C = εS / 4πkd, 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 decreases by 20% respectively.
[0093] In this embodiment, by using the first set of parameters in the initial stage of low-brightness screen display, the main pixel in the pixel unit is driven to light up while the auxiliary pixels are not; and by using the second set of parameters in the subsequent stage of low-brightness screen display, both the main pixel and the auxiliary pixels in the pixel unit are driven to light up. This reduces the capacitance of the pixels in the pixel unit in the initial stage of low-brightness screen display, increases the brightness of the first frame when the pixels are lit, and improves defects such as ghosting, temperature drift, green tinge, and on-hook during low-brightness screen switching, thus optimizing the image quality of low-brightness screens. At the same time, it ensures that the display optical performance (such as color shift, lifespan, efficiency, reliability, etc.) of the display panel does not change in normal brightness mode (i.e., display brightness of approximately 350-800 nits).
[0094] In some embodiments, the initial stage consists of the first 1 to 5 frames when the low-brightness screen begins to be displayed; the subsequent stage consists of other frames during the low-brightness screen display.
[0095] In this embodiment, referring to Figure 2a, which shows the low grayscale ghosting curve of a display panel with only main pixels in the pixel unit of the related technology, and Figure 2b, which shows the low grayscale ghosting curve of the display panel in this embodiment, it can be seen that the coverage area of the initial three peaks of the low grayscale ghosting curve in this embodiment is significantly larger than that of the initial three peaks of the low grayscale ghosting curve in the related technology in the initial stage of low brightness image display. The actual measurement results show that the ghosting WFFR (i.e., the ratio of the brightness of the first frame of the low brightness image to the average brightness of the first 5 frames) of the low grayscale ghosting curve of the display panel in this embodiment is improved by 27.9% compared with the ghosting WFFR (i.e., the ratio of the brightness of the first frame of the low brightness image to the average brightness of the first 5 frames) of the low grayscale ghosting curve of the display panel in the related technology. That is, the pixel design and driving method of the display panel in this embodiment significantly improve the ghosting defects that occur when displaying low brightness images. Meanwhile, referring to Figure 2c, the color shift level (color shift level in the CIE1931 color space) of the display panel in this embodiment and the display panel in the related technology is no different from that in the normal brightness mode (i.e., the display brightness is about 350-800 nits). Furthermore, the lifespan of the display panel in this embodiment and the display panel in the related technology is no different when the pixel aperture ratio is the same. Under the same brightness and the same chromaticity, the white light efficiency of the two is no different.
[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, while the auxiliary pixel does 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 temperature and low temperature, the first set of parameters drives the main pixel in the pixel unit to light up, while the auxiliary pixel does not light up.
[0097] In some embodiments, the normal temperature range is 0℃ to 35℃; the high temperature range is greater than 35℃; and the low temperature range is less than 0℃.
[0098] By driving the low-brightness screen 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. This not only improves the ghosting problem when switching between low-brightness screens, but also improves the temperature drift problem when displaying low-brightness screens at high temperature and low temperature.
[0099] In this embodiment, referring to Figure 3a, which shows the temperature drift result of a display panel with only main pixels in the pixel unit of the related technology, and Figure 3b, which shows the temperature drift result of the display panel in this embodiment, it can be seen that the temperature drift result of this embodiment is significantly improved compared to the related technology display panel when displaying low-brightness images. As can be seen from Figure 3a, the temperature drift (i.e., chromaticity shift) ΔWy of the low-brightness image of the display panel in the related technology at low temperature is 0.2 to 0.3 (this ΔWy is the difference between Wy at low temperature and Wy at room temperature in the CIE1931 color space); as can be seen from Figure 3b, the temperature drift (i.e., chromaticity shift) ΔWy of the low-brightness image of the display panel in this embodiment at low temperature is 0 to 0.04 (this ΔWy is the difference between Wy at low temperature and Wy at room temperature in the CIE1931 color space); this embodiment and the related technology Compared with the structure and driving scheme of the display panel during surgery, the display effect of low brightness image at low temperature is significantly improved from greenish to white light or slightly bluish. At the same time, as can be seen from Figures 3a and 3b, the temperature drift ΔWx (where ΔWx is the difference between Wx at high temperature and Wx at room temperature in the CIE1931 color space) and ΔWy (where ΔWy is the difference between Wy at high temperature and Wy at room temperature in the CIE1931 color space) of the display panel in this embodiment are also significantly reduced compared with the temperature drift ΔWx (where ΔWx is the difference between Wx at high temperature and Wx at room temperature in the CIE1931 color space) and ΔWy (where ΔWy is the difference between Wy at high temperature and Wy at room temperature in the CIE1931 color space) of the display panel in related technologies.
[0100] In this embodiment, Table 1 below 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] In Table 1, no optically related defects were found after 240 hours of operational tests such as 8585 (high temperature and high humidity operation test), THO (high temperature and high humidity operation test), LTO (low temperature operation test), and HTO (high temperature operation test). Similarly, no optically related defects were found 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), UV testing (light obstruction test), and HAST (high voltage accelerated aging test). Furthermore, referring to Figure 4, compared to the display panel design in related technologies, since the total aperture ratio and total aperture proportion of the pixels in the display panel of this embodiment are the same as those in related technologies, the lifespan of the display panel in this embodiment is consistent with that of the display panels in related technologies at the same brightness (e.g., 500 nits).
[0103] The display panel driving method provided in this embodiment drives the main pixels in the pixel unit to light up while the auxiliary pixels remain off during the initial stage of low-brightness screen display using a first set of parameters; and drives both the main pixels and auxiliary pixels in the pixel unit to light up during the subsequent stage of low-brightness screen display using a second set of parameters. This reduces the capacitance of the pixels in the pixel unit during the initial stage of low-brightness screen display, increases the brightness of the first frame when the pixels are lit, and improves issues such as ghosting, temperature drift, green tinge, and screen-on defects during low-brightness screen switching, thus optimizing the image quality of low-brightness screens. At the same time, it ensures that the display optical performance (such as color shift, lifespan, efficiency, reliability, etc.) of the display panel does not change in normal brightness mode (i.e., display brightness of approximately 350-800 nits).
[0104] This disclosure also provides a display device, including the display panel described in the above embodiments.
[0105] By adopting the display panel in the above embodiments, the display device improves defects such as ghosting, temperature drift, green tint, and on-hook when switching between low-brightness screens, and optimizes the image quality of low-brightness screens; at the same time, it ensures that the display optical performance of the display device does not change in normal brightness mode.
[0106] The display device provided in this disclosure can be any product or component with display function, such as an OLED panel, a QD-OLED panel, an OLED TV, an OLED billboard, a monitor, a mobile phone, or a navigator.
[0107] It is understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of this disclosure, and this disclosure is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and substance of this disclosure, and these modifications and improvements are also considered to be within the scope of protection of this disclosure.
Claims
1. A display panel having a display area, wherein, It includes multiple pixel units located in the display area; The pixel unit includes a main pixel and an auxiliary pixel; the aperture area of the main pixel is larger than the aperture area of the auxiliary pixel; A driving circuit, electrically connected to the pixel unit, is used to drive the main 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 remain off during the initial stage of low-brightness screen display. The second set of parameters is used to drive both the main pixel and the auxiliary pixel in the pixel unit to light up in the subsequent stage of the low-brightness screen display; The low-brightness screen refers to a screen with a brightness of less than 2 nits.
2. The display panel according to claim 1, wherein, It also includes the substrate and the pixel defining layer. The pixel defining layer is located on one side of the substrate, and the pixel defining layer has a plurality of first openings and a plurality of second openings; The main pixel includes a first sub-pixel, a second sub-pixel, and a third sub-pixel with different colors; The first sub-pixel, the second sub-pixel, and the third sub-pixel are each located in a different first opening; The auxiliary pixels include a first auxiliary sub-pixel, a second auxiliary sub-pixel, and a third auxiliary sub-pixel with different colors; The first auxiliary sub-pixel, the second auxiliary sub-pixel, and the third auxiliary sub-pixel are each located in a different second opening; 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; The opening area of the third sub-pixel is larger than the opening area of the third auxiliary sub-pixel.
4. The display panel according to claim 2, wherein, The main pixel includes a first electrode, a first light-emitting layer, and a second electrode. The first electrode, the first light-emitting layer, and the second electrode are stacked sequentially along a direction away from the substrate, and their orthogonal projections on the substrate at least partially overlap. The auxiliary pixel includes 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 stacked sequentially along a direction away from the substrate and their orthogonal 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 15% or more.
6. The display panel according to claim 2, wherein, The aperture ratio of the first sub-pixel, the second sub-pixel, and the third sub-pixel in the main pixel is the same as the aperture ratio of the first auxiliary sub-pixel, the second auxiliary sub-pixel, and the third auxiliary sub-pixel 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; Where N ranges from 1.1 to 2.0; and M ranges from 1.8 to 3.
0. Alternatively, N can range from 1.2 to 1.5, and M can range from 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 triangle, rectangle, circle, ellipse, polygon, and regular polygon; The orthographic projection shape of the auxiliary pixel on the substrate includes any one of triangle, rectangle, circle, ellipse, polygon, and 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 and second light-emitting layers may include quantum dots and organic light-emitting materials.
10. The display panel according to claim 1, wherein, Both the first set of parameters and the second set of parameters are Gamma 2.2 curves.
11. A display device, wherein, Includes the display panel as described in any one of claims 1-10.
12. A method for driving a 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 aperture area of the main pixel is larger than the aperture area of the auxiliary pixel; A driving circuit, electrically connected to the pixel unit, is used to drive the main pixel and the auxiliary pixel in the pixel unit to light up; The driving method includes: programming a first set of parameters and a second set of parameters into the driving circuit; When the display panel displays a low-brightness image, in the initial stage, the first set of parameters drives the main pixel in the pixel unit to light up, while the auxiliary pixels do not light up. In a 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 screen refers to a screen with a brightness of less than 2 nits.
13. The driving method for a display panel according to claim 12, wherein, 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, while the auxiliary pixels do not light up. In a 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 under high and low temperatures, the first set of parameters drives the main pixel in the pixel unit to light up, while the auxiliary pixels remain off.
14. The driving method for a display panel according to claim 13, wherein, The initial stage refers to the first 1 to 5 frames of the low-brightness screen display at the start of the display. The subsequent stage refers to other frames displayed during the low-brightness screen display.
15. The driving method for a display panel according to claim 13, wherein, The ambient temperature range is 0℃~35℃; The temperature range of the high temperature is greater than 35°C; The low temperature range is less than 0°C.