Display panel, display device and luminance decay detection and compensation method

Abstract

The application provides a display panel, a display device and a brightness attenuation detection and compensation method. By setting the preset service life of the sub-pixel and the reverse matching of the channel geometric characteristics of the corresponding photosensitive element, the amplitude of the photoelectric current generated by each photosensitive element is basically consistent, which is conducive to the comparison of the photoelectric current corresponding to each sub-pixel by the subsequent algorithm, reduces the noise interference, improves the accuracy of the brightness attenuation detection, and thus more accurate brightness compensation is realized.

Description

Technical Field

[0001] This application relates to the field of display technology, and in particular to a display panel, display device, and method for detecting and compensating for brightness attenuation. Background Technology

[0002] OLED (Organic Light-Emitting Diode) display devices have advantages such as self-illumination, high contrast, wide color gamut, and flexibility, and have been widely used in mobile phones, tablets, TVs, automotive displays and other fields.

[0003] In existing technologies, the degree of pixel brightness decay is determined by collecting the photocurrent of the photosensitive TFT (Thin-Film Transistor), and then brightness compensation is performed.

[0004] However, existing light-sensing detection solutions are inaccurate and prone to false compensation. Summary of the Invention

[0005] The main technical problem addressed by this application is to provide a display panel, display device, and brightness attenuation detection and compensation method, thereby solving the problem that the detection results of the existing light sensing detection scheme are inaccurate and prone to false compensation.

[0006] To address the aforementioned technical problems, the first technical solution provided in this application is: to provide a display panel, comprising: Multiple self-illuminating sub-pixels of different colors; and Multiple photosensitive elements are set up one-to-one with sub-pixels; the photosensitive elements are configured to receive the light emitted by the corresponding sub-pixel and generate photocurrent based on the intensity of the light; The preset lifetimes of multiple sub-pixels are arranged in ascending order, and the channel geometry features of the photosensitive elements corresponding to the multiple sub-pixels are arranged in descending order, so that the photocurrent amplitude generated by each photosensitive element is basically the same; wherein, the channel geometry features include the effective conductive area of ​​the channel or the width-to-length ratio of the channel.

[0007] In some embodiments, the photosensitive element is a coplanar thin-film transistor, and the channel geometry includes the channel width-to-length ratio.

[0008] In some embodiments, the photosensitive element is a three-dimensional thin-film transistor, and the channel geometry includes the effective conductive area of ​​the channel.

[0009] In some embodiments, the display panel includes three sub-pixels of different colors: a red pixel, a green pixel, and a blue pixel. The ratio of the channel geometry features of the photosensitive elements corresponding to the blue, green, and red pixels is (2.5~3.5):(1.5~2.5):1.

[0010] In some embodiments, the photosensitive element includes an active layer and an optical functional layer disposed on the surface of the active layer, wherein the number of optical functional layers is one or two. The optical functional layer is configured to regulate the propagation characteristics of incident light in order to improve the light absorption efficiency of the photosensitive element.

[0011] In some embodiments, the surface of the optical functional layer away from the active layer is recessed towards the interior of the optical functional layer to form a concave surface.

[0012] In some embodiments, the optical functional layer includes a first insulating layer and a second insulating layer sequentially stacked on the active layer along the thickness direction of the active layer, wherein the refractive index of the second insulating layer is greater than the refractive index of the first insulating layer, and the refractive index of the first insulating layer is greater than the refractive index of the active layer.

[0013] In some embodiments, at least one of the first and second insulating layers has its surface away from the active layer recessed towards the interior of the insulating layer to form a concave surface.

[0014] To address the aforementioned technical problems, the second technical solution provided in this application is: a brightness attenuation detection and compensation method for detecting and compensating the brightness of sub-pixels in the aforementioned display panel, comprising: The photocurrent output by the photosensitive element corresponding to each color sub-pixel is collected multiple times simultaneously. Calculate the brightness attenuation of the corresponding sub-pixel and determine the actual attenuation slope; The preset attenuation slope of the sub-pixel is compared with the actual attenuation slope to determine the attenuation status of the corresponding sub-pixel, and compensation is performed based on the attenuation status.

[0015] To solve the above-mentioned technical problems, the third technical solution provided in this application is: to provide a display device, which includes a detection compensation module and the above-mentioned display panel; The detection and compensation module is used to perform the brightness attenuation detection and compensation method described above.

[0016] The beneficial effects of this application are as follows: Unlike existing technologies, this application provides a display panel, a display device, and a method for detecting and compensating brightness attenuation. The display panel includes multiple self-emissive sub-pixels of different colors and multiple photosensitive elements. Each photosensitive element is configured to correspond one-to-one with a sub-pixel. The photosensitive elements are configured to receive light emitted from the corresponding sub-pixel and generate photocurrent based on the light intensity. The preset lifetimes of the multiple sub-pixels are arranged in ascending order, and the channel geometry features of the photosensitive elements corresponding to the multiple sub-pixels are arranged in descending order, so that the photocurrent amplitude generated by each photosensitive element is substantially consistent. The channel geometry features include the effective conductive area of ​​the channel or the channel width-to-length ratio. By setting the preset lifetime of the sub-pixels to be inversely matched with the channel geometry features of the corresponding photosensitive elements, the photocurrent amplitude generated by each photosensitive element is substantially consistent. This facilitates subsequent algorithm comparison of the photocurrent corresponding to each sub-pixel, reduces noise interference, improves the accuracy of brightness attenuation detection, and thus achieves more precise brightness compensation. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of a display panel according to an embodiment of the present application from a certain perspective; Figure 2 This is a structural schematic diagram of another embodiment of the display panel provided in this application; Figure 3 This is a schematic diagram of the structure of an embodiment of the photosensitive element provided in this application; Figure 4 This is a schematic diagram of another embodiment of the photosensitive element provided in this application; Figure 5 This is a schematic diagram of the structure of an embodiment of the photosensitive element corresponding to each color sub-pixel provided in this application; Figure 6 yes Figure 5 A cross-sectional view of an embodiment of FF; Figure 7 This is a flowchart illustrating one embodiment of the brightness attenuation detection and compensation method provided in this application; Figure 8 This is a schematic diagram of an embodiment of the display device provided in this application.

[0019] Explanation of icon numbers: 3. Display device; 2. Detection and compensation module; 1. Display panel; 10. Sub-pixel; 20. Photosensitive element; 21. Active layer; 22. Optical functional layer; 221. First insulating layer; 222. Second insulating layer; 23. Source; 24. Drain; 25. Isolation layer; 30. Driving transistor; 40. Substrate; 50. Encapsulation layer; 60. Data line; 70. Scan line; 80. Pixel area; 90. Channel; R. Red pixel; G. Green pixel; B. Blue pixel; L. Channel length; W. Channel width. Detailed Implementation

[0020] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0021] In the following description, specific details such as particular system architectures, interfaces, and technologies are presented for illustrative purposes rather than for limiting purposes, in order to provide a thorough understanding of this application.

[0022] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0023] The terms "first," "second," and "third" in this application are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first," "second," or "third" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified. All directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of this application are only used to explain the relative positional relationships and movements between components in a specific orientation (as shown in the figures). If the specific orientation changes, the directional indications also change accordingly. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or devices.

[0024] In this document, the term "exemplary" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one of the embodiments in this application. In the embodiments. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0025] Based on the principle of semiconductor photoelectric conversion, the core calculation formula for the operating current in the saturation region of a photosensitive TFT is: .

[0026] The parameters in the formula are defined as follows: : Current induced in the saturation region of the photosensitive TFT (unit: A); Photoelectric semiconductor carrier mobility (unit: ); Gate oxide capacitance (unit: ); : Channel width of photosensitive TFT (unit: μm); : TFT channel length (unit: μm); Gate-source drive voltage (unit: V); : Threshold voltage of photosensitive TFT (unit: V).

[0027] In existing planar light incidence structures, the light intensity is insufficient to effectively excite charge carriers, resulting in a small equivalent channel width and low charge carrier mobility. Single optical focusing can only utilize the forward incident light, and the light energy transmitted through the optoelectronic semiconductor is completely wasted, ultimately failing to meet the requirements for high-precision detection in the induced current.

[0028] Existing technologies in the field of display panel brightness decay detection have the following four significant drawbacks: 1. Weak blue light signal, resulting in a weak detection foundation: Blue pixels have lower brightness and faster aging and decay rates, causing the intensity of their emitted light signal to be significantly weaker than that of other color pixels. Given the limited size of photosensitive thin-film transistors (TFTs), the collected photocurrent is extremely weak, making it difficult to meet the minimum signal threshold requirements for high-precision detection.

[0029] 2. Low signal-to-noise ratio, limiting detection accuracy: The weak photocurrent directly leads to a low signal-to-noise ratio (SNR), significantly increasing the interference of environmental noise or circuit background noise on the detection signal. This high noise level severely reduces the accuracy and reliability of the detection results, easily leading to misjudgments.

[0030] 3. Channel signal imbalance, leading to erroneous algorithm compensation: Due to the differences in physical characteristics of the red, green, and blue (RGB) sub-pixels, the amplitude of their detected signals exhibits significant inconsistencies. The algorithm struggles to effectively distinguish between the true brightness decay trend and random noise fluctuations in low signal-to-noise ratio environments, resulting in errors in the compensation logic and leading to overcompensation or undercompensation.

[0031] 4. Limited hardware optimization impacts display performance: Attempting to enhance signal acquisition capabilities by increasing the size of the photosensitive TFT will directly reduce the effective aperture ratio of the pixels. This will not only further reduce the overall brightness of the display panel but also increase driving power consumption, thus negatively restricting the display effect and creating a dilemma between "improving detection accuracy" and "maintaining display performance".

[0032] Please see Figures 1 to 4 , Figure 1 This is a schematic diagram of the structure of a display panel according to an embodiment of the present application from a certain perspective. Figure 2 This is a schematic diagram of the structure of an embodiment of the display panel provided in this application from another perspective. Figure 3 This is a schematic diagram of the structure of an embodiment of the photosensitive element provided in this application. Figure 4 This is a schematic diagram of another embodiment of the photosensitive element provided in this application.

[0033] This application provides a display panel 1, wherein the display panel 1 includes a plurality of self-emissive sub-pixels 10 of different colors and a plurality of photosensitive elements 20. The plurality of photosensitive elements 20 are respectively disposed in one-to-one correspondence with the sub-pixels 10; the photosensitive elements 20 are configured to receive light emitted from the corresponding sub-pixel 10 and generate photocurrent based on the intensity of the light; wherein the preset lifetimes of the plurality of sub-pixels 10 are arranged in ascending order of shortest, and the channels 90 of the photosensitive elements 20 corresponding to the plurality of sub-pixels 10 (see...) Figure 5 The geometric features are arranged in descending order so that the photocurrent amplitude generated by each photosensitive element 20 is basically the same; wherein, the geometric features of the channel 90 include the effective conductive area of ​​the channel 90 or the width-to-length ratio of the channel 90.

[0034] The preset lifetimes of multiple sub-pixels 10 are arranged in ascending order, and the channel 90 geometric features of the corresponding photosensitive elements 20 are arranged in descending order. That is, the preset lifetime of sub-pixels 10 and the channel 90 geometric features of the corresponding photosensitive elements 20 are inversely matched. The preset lifetime of sub-pixels 10 refers to the time, calculated based on accelerated aging test data and using a mathematical model (such as an exponential decay model or the Arrhenius equation), corresponding to the time when the luminous intensity of sub-pixels 10 decays to a predetermined proportion (e.g., 95%, 70%, or 50%) of the initial brightness under specific standard initial brightness and environmental conditions.

[0035] By setting the preset lifespan of sub-pixel 10 to be inversely matched with the geometric features of the channel 90 of the corresponding photosensitive element 20, the photocurrent amplitude generated by each photosensitive element 20 is basically consistent. This is beneficial for subsequent algorithms to compare the photocurrent corresponding to each sub-pixel 10, reduce noise interference, improve the accuracy of brightness attenuation detection, and thus achieve more accurate brightness compensation.

[0036] Specifically, the sub-pixels 10 with shorter preset lifetimes correspond to larger channel 90 geometric features, thus generating sufficient photocurrent amplitude even when the light signal is weak, improving the signal-to-noise ratio under weak light conditions. At the same time, the sub-pixels 10 with longer preset lifetimes correspond to smaller channel 90 geometric features, avoiding photocurrent saturation when the light signal is strong, and achieving a balance of multi-path photocurrent amplitudes.

[0037] "The photocurrent amplitude is basically consistent" means that the difference in photocurrent amplitude is within the allowable error range, such as within ±5%, or within the signal-to-noise ratio tolerance allowed by the circuit.

[0038] For example, the photocurrent amplitude generated by each photosensitive element 20 is consistent, which can further improve the accuracy of brightness decay detection.

[0039] For example, sub-pixel 10 is an organic light-emitting diode (OLED).

[0040] For example, sub-pixel 10 is a top-emitting structure, and photosensitive element 20 is located on the side of sub-pixel 10 and on the backlight side of sub-pixel 10. The backlight side is the surface directly opposite the main emitting surface of sub-pixel 10.

[0041] In some specific embodiments, the display panel 1 includes multiple data lines 60 and multiple scan lines 70, which intersect to define multiple pixel regions 80. Sub-pixels 10 and corresponding photosensitive elements 20 are disposed within the pixel regions 80.

[0042] In some embodiments, the display panel 1 further includes a driving transistor 30, which is connected to the sub-pixel 10 to control the light emission of the sub-pixel 10.

[0043] For example, the photosensitive element 20 is located on the side of the driving transistor 30 and between the photosensitive element 20 and the sub-pixel 10.

[0044] Furthermore, specifically, the display panel 1 also includes a substrate 40 and an encapsulation layer 50. A driving transistor 30 is disposed on the substrate 40, and a photosensitive element 20 is offset from the driving transistor 30 in the thickness direction of the substrate 40. The photosensitive element 20 is located on the side of the driving transistor 30 away from the substrate 40. A sub-pixel 10 is located on the side of the photosensitive element 20 away from the substrate 40 and is offset from the photosensitive element 20 in the thickness direction of the substrate 40. The encapsulation layer 50 covers the substrate 40 and is located on the side of the sub-pixel 10 away from the substrate 40.

[0045] The encapsulation layer 50 can be a single-layer or multi-layer structure, which is not limited here and can be selected according to actual needs. In some embodiments, the substrate 40 is a rigid substrate, such as a glass substrate; in other embodiments, the substrate 40 is a flexible substrate, such as a flexible polyimide substrate. Exemplarily, the photosensitive element 20 can be a photosensitive device with a thin-film transistor structure.

[0046] The photosensitive element 20 is configured to receive light emitted from the corresponding sub-pixel 10. The light shines on the photoelectric conversion region (i.e., active layer 21) of the photosensitive element 20, and a photocurrent is generated based on the intensity of the light. The magnitude of the photocurrent is proportional to the intensity of the received light.

[0047] The aspect ratio of the channel 90 of the photosensitive element 20 refers to the channel width W (see...). Figure 5 ) and channel length L (see Figure 5 The ratio of ).

[0048] The effective conductive area of ​​the channel 90 of the photosensitive element 20 refers to the effective area of ​​the photosensitive element 20 that actually participates in photoelectric conversion.

[0049] In some embodiments, the photosensitive element 20 is a coplanar thin-film transistor, and the geometry of the channel 90 includes the width-to-length ratio of the channel 90.

[0050] A coplanar thin-film transistor structure typically includes an active layer 21, a gate (not shown), a source 23, and a drain 24 located on a substrate 40. The source 23 and drain 24 are located on opposite sides of the active layer 21, while the gate is located above the active layer 21 and isolated by a gate dielectric layer. The channel 90 is the conductive region of the active layer 21 formed between the source 23 and drain 24 by the gate electric field. The coplanar structure is advantageous for manufacturing using standard semiconductor processes, and its channel 90 plane is parallel to the substrate 40. The channel length L refers to the effective conductive distance of the active layer 21 between the source 23 and drain 24 along the current direction, while the channel width W refers to the effective widening of this conductive region perpendicular to the current direction. By adjusting the dimensions of the channel width W and channel length L, the aspect ratio of the channel 90 of the photosensitive element 20 can be precisely controlled.

[0051] The defined 90-degree aspect ratio of the channel allows for precise control of the photocurrent gain of the photosensitive element 20 by adjusting the ratio of the channel width W to the channel length L. For weak light signals, a larger 90-degree aspect ratio increases the effective photosensitive area or carrier transport channels, thereby increasing the photocurrent amplitude and improving the signal-to-noise ratio. For strong light signals, a smaller 90-degree aspect ratio limits the photocurrent amplitude and prevents signal saturation. This differentiated design based on the 90-degree aspect ratio of the coplanar thin-film transistor channel enables the photosensitive elements 20 corresponding to different color sub-pixels 10 to output photocurrent signals with similar amplitudes. This facilitates the subsequent circuitry to synchronously acquire and compare multiple photocurrents, reduces noise interference, improves the accuracy of brightness attenuation detection, and thus achieves more precise brightness compensation.

[0052] In other embodiments, the photosensitive element 20 is a three-dimensional thin-film transistor, and the geometry of the channel 90 includes the effective conductive area of ​​the channel 90.

[0053] For example, three-dimensional thin-film transistors include vertical thin-film transistors (TFTs), FinFET-style thin-film transistors (TFTs), or stacked or multi-layer thin-film transistors (TFTs).

[0054] Three-dimensional thin-film transistors (TFTs) possess a three-dimensional channel 90 structure, such as a fin structure or a nanosheet structure, allowing the channel 90 region to exist not only on the surface of the active layer 21 but also extend vertically. The effective conductive area of ​​the channel 90 refers to the total physical surface area within the light-irradiated region that actually participates in photoelectric conversion and forms a carrier transport channel. In the three-dimensional structure, due to the presence of the sidewalls and top surface of the channel 90, the effective conductive area of ​​the channel 90 is significantly larger than that of a planar structure with the same projected area. For example, a photosensitive layer can be placed on the side of the fins of the three-dimensional TFT, allowing light to enter from the side and excite carriers. Alternatively, a nanosheet structure can be used, allowing light to enter simultaneously from both above and below, fully utilizing light energy.

[0055] By configuring the photosensitive element 20 as a three-dimensional thin-film transistor, its three-dimensional channel 90 structure increases the effective conductive area of ​​the channel 90, enabling the capture of more photons and the generation of photogenerated carriers per unit projected area, thereby achieving a larger photocurrent amplitude under the same low-light conditions. This structure allows the photosensitive element 20 corresponding to the short-lifespan sub-pixel 10 to improve signal strength by increasing the effective photosensitive area without increasing the planar footprint, effectively improving the signal-to-noise ratio under low brightness or high attenuation conditions, and helping to reduce noise interference with the detection results. At the same time, the large conductive area brought by the three-dimensional structure makes the adjustment of the channel 90 geometry more flexible. The effective conductive area can be precisely controlled by adjusting the fin height, number, or number of nanosheet layers, thereby achieving fine matching of multi-path photocurrent amplitudes and improving the accuracy of brightness attenuation detection and the precision of compensation.

[0056] Furthermore, this application suppresses noise interference by optimizing the geometric features of the channel 90 of the photosensitive element 20, thereby effectively improving the detection signal-to-noise ratio and accuracy without uniformly increasing the size of the photosensitive element 20. This solution avoids squeezing the effective aperture ratio of pixels due to increasing the device area, and successfully achieves a balance between "improving detection accuracy" and "maintaining display performance".

[0057] Furthermore, in some embodiments, the photosensitive element 20 includes an active layer 21 and an optical functional layer 22 disposed on the surface of the active layer 21, wherein the number of optical functional layers 22 is one or two; wherein the optical functional layer 22 is configured to regulate the propagation characteristics of incident light to improve the light absorption efficiency of the photosensitive element 20.

[0058] In some specific embodiments, such as Figure 3 As shown, there is one optical functional layer 22, located on the side of the active layer 21 facing the sub-pixel 10. In some other embodiments, there are two optical functional layers 22, located on opposite sides of the active layer 21 along its thickness direction.

[0059] For example, the photosensitive element 20 also includes a source 23 and a drain 24, the source 23 passing through the optical functional layer 22 and connected to the active layer 21, and the drain 24 passing through the optical functional layer 22 and connected to the active layer 21.

[0060] The active layer 21 is the semiconductor region in the photosensitive element 20 where photoelectric conversion occurs. It is used to absorb photons and generate electron-hole pairs, thereby forming a photocurrent.

[0061] The optical functional layer 22 is configured to modulate the propagation characteristics of incident light. This means that the optical functional layer 22 optimizes the distribution and path of light inside the photosensitive element 20 by changing the reflection, refraction, scattering or absorption behavior of light, thereby increasing the capture probability of photons by the active layer 21, that is, improving the light absorption efficiency of the photosensitive element 20.

[0062] By setting the optical functional layer 22 on the surface of the active layer 21, the incident light undergoes propagation characteristic modulation before reaching the active layer 21, reducing reflection and scattering losses at the interface and improving the transmission efficiency of light energy to the active layer 21. Simultaneously, by controlling the focusing or guiding effect of the incident light, the light is more concentrated in the effective photosensitive area of ​​the active layer 21, increasing the probability of photon interaction with the semiconductor material and thus improving light absorption efficiency. This structure enables the photosensitive element 20 to generate a stronger photocurrent response when receiving weak light signals, further improving the signal-to-noise ratio under weak light conditions. This facilitates more accurate detection of attenuation in weak light sources such as blue pixel B, achieving low-noise detection. Furthermore, the introduction of the optical functional layer 22 optimizes the optical path distribution, making the photosensitive element 20 more stable in its sensitivity to the angle and position of the incident light, which helps improve the consistency and reliability of detection results, thereby enabling more accurate execution of brightness compensation algorithms.

[0063] In some embodiments, the surface of the optical functional layer 22 away from the active layer 21 is recessed towards the interior of the optical functional layer 22 to form a concave surface.

[0064] The optical functional layer 22 has a single-layer or multi-layer structure.

[0065] The surface of the optical functional layer 22 away from the active layer 21 is set as a concave surface. This concave surface design can convert the incident light into large-angle oblique light to improve the light absorption efficiency of the active layer 21 in the photosensitive element 20.

[0066] This concave design utilizes the principle of light refraction at curved interfaces to refract light rays entering the optical functional layer 22 from different incident angles, altering their propagation paths. When light strikes the optical functional layer 22, the concave structure allows parallel or divergent light rays to converge towards the central axis, or reduces total internal reflection at specific angles, thereby guiding more light energy to the underlying active layer 21. The convergence angle of the light rays can be precisely adjusted by controlling the radius of curvature and depth of the concave surface to match the photosensitive area of ​​the photosensitive element 20, reducing light escape from the sidewalls.

[0067] This structure utilizes the geometric properties of a concave surface to increase the ability to capture non-perpendicular incident light, enabling the effective utilization of light from different emission angles of the sub-pixel 10, thereby improving the overall light absorption efficiency.

[0068] Furthermore, in some embodiments, the optical functional layer 22 includes a first insulating layer 221 and a second insulating layer 222 sequentially stacked on the active layer 21 along the thickness direction of the active layer 21. The refractive index of the second insulating layer 222 is greater than the refractive index of the first insulating layer 221, and the refractive index of the first insulating layer 221 is greater than the refractive index of the active layer 21.

[0069] For example, the first insulating layer 221 is a silicon dioxide layer.

[0070] The first insulating layer 221 is located on the surface of the second insulating layer 222 near the active layer 21.

[0071] The refractive index of the second insulating layer 222 is set to be greater than that of the first insulating layer 221, which in turn is greater than that of the active layer 21, thus forming a refractive index gradient that decreases sequentially from the second insulating layer 222 to the first insulating layer 221 and the active layer 21. This refractive index gradient design causes the propagation path of light to be deflected when it travels from a high-refractive-index medium to a low-refractive-index medium. Specifically, when light is incident on the surface of the second insulating layer 222 at a certain angle, its propagation speed decreases due to the higher refractive index of the second insulating layer 222. When light enters the first insulating layer 221, which has a lower refractive index, it is further deflected towards the normal or its propagation angle is changed. This angle adjustment helps to guide the incident light more concentratedly to the photosensitive area of ​​the active layer 21.

[0072] For example, a small roughness or microstructure may be designed at the interface between the second insulating layer 222 and the first insulating layer 221 to achieve more complex light scattering or total internal reflection control in conjunction with the refractive index gradient.

[0073] By setting a first insulating layer 221 and a second insulating layer 222 with specific refractive index gradient distributions, the incident light is guided and modulated by the refractive index change during propagation. This allows the light to converge more concentratedly onto the photosensitive area of ​​the active layer 21, increasing the path density and interaction probability of photons within the active layer 21, thereby further improving light absorption efficiency. The combination of the high refractive index of the second insulating layer 222 and the low refractive index of the first insulating layer 221 facilitates the formation of an optical waveguide effect or focusing effect, effectively capturing and guiding light that might otherwise be scattered or reflected into the active layer 21, reducing interface reflection losses. This structure enables the photosensitive element 20 to generate a stronger photocurrent response when receiving weak light signals, significantly improving the signal-to-noise ratio under weak light conditions. This facilitates more accurate detection of attenuation in weak light sources such as blue pixel B, achieving low-noise detection. Meanwhile, the design of the refractive index gradient optimizes the optical path distribution, making the sensitivity of the photosensitive element 20 to the angle and position of the incident light more stable. This is beneficial to improving the consistency and reliability of the detection results, thereby enabling more accurate execution of the brightness compensation algorithm and avoiding false compensation caused by excessive differences in photocurrent amplitude.

[0074] Furthermore, in some embodiments, at least one of the first insulating layer 221 and the second insulating layer 222 has its surface away from the active layer 21 recessed toward the interior of the insulating layer itself to form a concave surface.

[0075] The first insulating layer 221 is in contact with the second insulating layer 222.

[0076] The surface of the first insulating layer 221 away from the active layer 21 is recessed towards the interior of the first insulating layer 221 to form a concave surface, and / or the surface of the second insulating layer 222 away from the active layer 21 is recessed towards the interior of the second insulating layer 222 to form a concave surface.

[0077] For example, the surface of the first insulating layer 221 away from the active layer 21 is recessed towards the interior of the first insulating layer 221 to form a concave surface, and the surface of the second insulating layer 222 away from the active layer 21 is recessed towards the interior of the second insulating layer 222 to form a concave surface. Specifically, the concave surface is an arc surface, and in the thickness direction of the active layer 21, the distance between the lowest points of the two oppositely disposed surfaces of the second insulating layer 222 is greater than the distance between the lowest points of the two oppositely disposed surfaces of the first insulating layer 221.

[0078] By setting at least one of the insulating layers 221 and 222 to a concave surface away from the active layer 21, incident light rays converge and refract as they pass through this surface. The light rays are guided and concentrated onto the photosensitive area of ​​the active layer 21, increasing the light intensity density on the photosensitive surface of the active layer 21, thereby further enhancing the photocurrent signal intensity. This concave structure, combined with the refractive index gradient, forms a compound lens effect, enabling weak light signals (especially the weak light emitted by blue pixel B) to be captured and enhanced more effectively. This significantly improves the signal-to-noise ratio under low-light conditions and facilitates more accurate identification of attenuated signals.

[0079] Please see Figures 1 to 6 , Figure 5 This is a schematic diagram of the structure of an embodiment of the photosensitive element corresponding to each color sub-pixel provided in this application. Figure 6 yes Figure 5 A cross-sectional view of an embodiment of FF.

[0080] In some embodiments, the display panel 1 includes three sub-pixels 10 of different colors, namely red pixel R, green pixel G and blue pixel B; the ratio of the geometric features of the channel 90 of the photosensitive element 20 corresponding to each of the blue pixel B, green pixel G and red pixel R is (2.5~3.5):(1.5~2.5):1.

[0081] For example, the photosensitive element 20 is a coplanar thin-film transistor, and the aspect ratio of the channel 90 of the photosensitive element 20 corresponding to the blue pixel B, green pixel G, and red pixel R is 3:2:1. For example, as Figure 5 As shown, the channel length L of each sub-pixel 10 is the same, and is 8 micrometers. The channel width W of the sub-pixels 10 of different colors is different. The channel width W of the photosensitive element 20 corresponding to the blue pixel B, green pixel G and red pixel R are 12 micrometers, 8 micrometers and 4 micrometers respectively.

[0082] In other embodiments, the channel width W corresponding to sub-pixels 10 of different colors may be different, and / or the channel length L corresponding to sub-pixels 10 of different colors may be different.

[0083] In other embodiments, the effective conductive area ratio of the channel 90 of the photosensitive element 20 corresponding to the blue pixel B, green pixel G, and red pixel R is 3.5:2:1, or it can be 2.5:1.5:1.

[0084] In other embodiments, the ratio of the geometric features of the channel 90 of the photosensitive element 20 corresponding to each of the blue pixel B, green pixel G, and red pixel R is 2.5:1.5:1, or the ratio of the geometric features of the channel 90 of the photosensitive element 20 corresponding to each of the blue pixel B, green pixel G, and red pixel R is 2.5:2:1; or the ratio of the geometric features of the channel 90 of the photosensitive element 20 corresponding to each of the blue pixel B, green pixel G, and red pixel R is 3.5:2.5,1.

[0085] Because blue pixels (B) decay rapidly and have a short preset lifespan, they emit weaker light signals. Therefore, the corresponding photosensitive element 20 uses a larger aspect ratio or a larger effective conductive area of ​​the channel 90 to generate a larger photocurrent in low light. Conversely, red pixels (R) decay slowly and have a long preset lifespan, emitting stronger light signals. The corresponding photosensitive element 20 uses a smaller aspect ratio or a smaller effective conductive area of ​​the channel 90 to avoid excessive photocurrent. This differentiated design makes the photocurrent amplitude output by the photosensitive element 20 corresponding to different color sub-pixels tend to be consistent. This helps to eliminate algorithm judgment errors caused by excessive differences in photocurrent amplitude, thereby achieving more accurate contrast attenuation detection and reducing the probability of false compensation.

[0086] In some embodiments, such as Figure 6 As shown, in the photosensitive element 20, an isolation layer 25 is further disposed between the source electrode 23 and the active layer 21, and / or an isolation layer 25 is further disposed between the drain electrode 24 and the active layer 21, to suppress dark current and enhance photoresponse. In other embodiments, the isolation layer 25 may be omitted.

[0087] Please see Figure 1 and Figure 7 , Figure 7 This is a flowchart illustrating one embodiment of the brightness attenuation detection and compensation method provided in this application.

[0088] This application provides a brightness attenuation detection and compensation method for detecting and compensating the brightness of sub-pixels in the aforementioned display panel. The brightness attenuation detection and compensation method includes: Step S1: Simultaneously acquire the photocurrent output by the photosensitive element corresponding to each color sub-pixel multiple times; Step S2: Calculate the brightness attenuation of the corresponding sub-pixel and determine the actual attenuation slope; Step S3: Compare the preset attenuation slope and the actual attenuation slope of the sub-pixel to determine the attenuation status of the corresponding sub-pixel, and perform compensation based on the attenuation status.

[0089] For example, within the same frame or the same refresh cycle, the photocurrent output by the photosensitive element 20 corresponding to multiple sub-pixels 10 of different colors is simultaneously acquired. Simultaneous acquisition eliminates time difference errors caused by inter-frame flicker or brightness fluctuations. Timing analysis is then performed on the photocurrent data acquired continuously across multiple frames.

[0090] Specifically, in some embodiments, multiple sub-pixels 10 of different colors constitute a pixel unit. There are multiple pixel units. Within each pixel unit, there is one sub-pixel 10 of the same color. For example, a pixel unit includes three sub-pixels 10, namely a red pixel R, a blue pixel B, and a green pixel G. Exemplarily, within the same frame or the same refresh cycle, the photocurrent output by the photosensitive element 20 corresponding to each sub-pixel 10 within the same pixel unit is synchronously acquired. Within the same refresh cycle, the data of the photosensitive element 20 corresponding to each sub-pixel 10 within the pixel unit is synchronously read. This "unit-level synchronization" strategy not only improves detection efficiency but also ensures that the color data required for white balance correction has a high degree of correlation at the same time.

[0091] During the factory manufacturing or initialization phase of the display panel 1, an initial reference current value (i.e., an initial photocurrent value) is established for the photosensitive element 20 corresponding to each sub-pixel 10, serving as a reference for subsequent attenuation judgment. The initial reference current value reflects the photoelectric conversion efficiency of the sub-pixel 10 in a healthy state.

[0092] The photocurrent of the photosensitive element 20 corresponding to different color sub-pixels 10 at the current moment is collected in real time, and the real-time photocurrent corresponding to each sub-pixel 10 is compared with its corresponding initial reference current value. By calculating the difference or ratio between the two, the brightness decay at the current moment is obtained. The implementation method provided in this application does not rely solely on a single measurement, but performs time-series analysis on photocurrent data collected continuously over multiple frames, and constructs a brightness decay curve that changes over time through data fitting techniques (such as linear regression or curve fitting). The actual decay slope is extracted from this brightness decay curve. This actual decay slope intuitively reflects the rate at which brightness decreases with usage time (e.g., the percentage of brightness loss per unit time).

[0093] The calculated actual attenuation slope is compared with its corresponding preset attenuation slope to determine the health status of sub-pixel 10, and a differentiated compensation strategy is executed accordingly.

[0094] The preset attenuation slope is a standard reference value pre-set based on the aging characteristic curve of the sub-pixel 10 material (such as OLED organic light-emitting material). Due to differences in material stability, the preset slope of different color sub-pixels 10 can be set independently.

[0095] For example, if the actual attenuation slope of sub-pixel 10 falls within the allowable preset slope deviation range, it is determined that sub-pixel 10 is in a normal natural aging process. If the actual attenuation slope of sub-pixel 10 exceeds the allowable preset slope deviation range (for example, if the actual attenuation slope is too large, it indicates a sudden drop in brightness), it is determined that sub-pixel 10 has an abnormal fault or accelerated degradation.

[0096] Based on the judgment results, the system dynamically generates compensation coefficients and adjusts the driving voltage or current output by the driver chip to achieve brightness restoration and white balance correction.

[0097] For example, when the overall aging is determined to be normal, the average brightness decay ratio of all sub-pixels 10 is calculated, a global brightness compensation coefficient is generated, and the overall luminous intensity of sub-pixels 10 is increased by increasing the driving current to restore it to the target initial brightness level.

[0098] Given that the aging rates of different color sub-pixels (10) often differ (e.g., blue pixel B typically ages faster than red pixel R), a simple global gain would lead to white balance shifts (making the image appear warmer or cooler). Based on white balance correction requirements, independent color gain coefficients are generated for each sub-pixel (10). For example, if blue pixel B is detected to be aging faster than red pixel R, the algorithm will apply greater gain compensation to blue pixel B and less to red pixel R. This asymmetric compensation mechanism improves overall brightness while precisely offsetting color shifts caused by color temperature drift, ensuring that the color coordinates of white images remain constant.

[0099] The final generated global brightness compensation coefficient and the color gain coefficient of each color sub-pixel 10 are written into the display driver chip. The display driver chip corrects the drive signal output to each sub-pixel 10 according to the compensation coefficient, completing the closed-loop operation from detection to compensation.

[0100] By acquiring the photocurrent output from the photosensitive element 20 and calculating the actual attenuation slope, the dynamic trend of the brightness change of sub-pixel 10 over time can be obtained, making the monitoring of brightness attenuation more continuous and accurate. By comparing the preset attenuation slope with the actual attenuation slope, a standardized judgment criterion can be established, enabling the system to quantify the aging degree of sub-pixel 10 and further improving the objectivity and consistency of the detection results. The design of photosensitive elements 20 with differentiated sizes ensures that the photocurrent amplitude generated by sub-pixels 10 of different colors is on the same order of magnitude, which helps improve the signal-to-noise ratio. This allows for effective elimination of noise interference when comparing the preset attenuation slope with the actual attenuation slope, making the determined attenuation situation more reliable and avoiding misjudgments caused by differences in signal strength.

[0101] Please see Figure 1 and Figure 8 , Figure 8This is a schematic diagram of an embodiment of the display device provided in this application.

[0102] This application provides a display device 3, wherein the display device 3 includes a detection compensation module 2 and the aforementioned display panel 1; the detection compensation module 2 is used to perform the aforementioned brightness attenuation detection and compensation method.

[0103] The display device 3 may also include one or more of the following components (not shown in the figures): memory, power supply component, processing component, multimedia component, audio component, input / output (I / O) interface, sensor component, and communication component. The specific structure and function of these components are the same as or similar to those in related technologies; please refer to the related technologies for details, which will not be repeated here. The display device 3 may be a computer, digital broadcasting terminal, messaging device, game console, medical device, fitness equipment, personal digital assistant, mobile phone, tablet, television, vehicle display, etc. This application does not limit its scope; the device may be selected according to actual needs.

[0104] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0105] The above are merely embodiments of this application and do not limit the scope of patent protection of this application. Any equivalent structural or procedural changes made using the content of this application’s specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of this application.

Claims

1. A display panel, characterized in that, include: Multiple self-illuminating sub-pixels with different colors; as well as Multiple photosensitive elements are respectively arranged in a one-to-one correspondence with the sub-pixel; the photosensitive elements are configured to receive light emitted by the corresponding sub-pixel and generate photocurrent based on the intensity of the light. The preset lifetimes of the multiple sub-pixels are arranged in ascending order, and the channel geometry features of the photosensitive elements corresponding to the multiple sub-pixels are arranged in descending order, so that the photocurrent amplitude generated by each photosensitive element is basically the same; wherein, the channel geometry features include the effective conductive area of ​​the channel or the width-to-length ratio of the channel.

2. The display panel according to claim 1, characterized in that, The photosensitive element is a coplanar thin-film transistor, and the channel geometry includes the channel width-to-length ratio.

3. The display panel according to claim 1, characterized in that, The photosensitive element is a three-dimensional thin-film transistor, and the channel geometry includes the effective conductive area of ​​the channel.

4. The display panel according to claim 1, characterized in that, The display panel includes three sub-pixels of different colors: a red pixel, a green pixel, and a blue pixel. The ratio of the channel geometry features of the photosensitive elements corresponding to the blue pixel, the green pixel, and the red pixel is (2.5~3.5):(1.5~2.5):

1.

5. The display panel according to claim 1, characterized in that, The photosensitive element includes an active layer and an optical functional layer disposed on the surface of the active layer, wherein the number of optical functional layers is one or two; The optical functional layer is configured to regulate the propagation characteristics of incident light in order to improve the light absorption efficiency of the photosensitive element.

6. The display panel according to claim 5, characterized in that, The side of the optical functional layer away from the active layer is recessed towards the interior of the optical functional layer to form a concave surface.

7. The display panel according to claim 5, characterized in that, The optical functional layer includes a first insulating layer and a second insulating layer sequentially stacked on the active layer along the thickness direction of the active layer. The refractive index of the second insulating layer is greater than that of the first insulating layer, and the refractive index of the first insulating layer is greater than that of the active layer.

8. The display panel according to claim 7, characterized in that, At least one of the first insulating layer and the second insulating layer has its surface away from the active layer recessed towards the interior of the insulating layer to form a concave surface.

9. A method for detecting and compensating for brightness attenuation, used to detect and compensate for the brightness of sub-pixels in a display panel according to any one of claims 1 to 8, characterized in that, include: The photocurrent output by the photosensitive element corresponding to each color sub-pixel is collected multiple times simultaneously. Calculate the brightness attenuation of the corresponding sub-pixel and determine the actual attenuation slope; The preset attenuation slope of the sub-pixel is compared with the actual attenuation slope to determine the attenuation status of the corresponding sub-pixel, and compensation is performed based on the attenuation status.

10. A display device, characterized in that, Includes a detection compensation module and a display panel as described in any one of claims 1 to 8; The detection and compensation module is used to execute the brightness attenuation detection and compensation method as described in claim 9.

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