Pixel unit, display panel and control system and control method thereof

Abstract

The application belongs to the technical field of semiconductors, and discloses a pixel unit, a display panel, and a control system and control method thereof. The pixel unit comprises an anode, sub-anodes corresponding to different color sub-pixels, each color pixel corresponding to the sub-anode comprising at least two mutually isolated sub-electrodes; and a driving circuit for independently controlling the on-off state of each sub-electrode to dynamically adjust the effective light-emitting area of each sub-pixel. By independently controlling the on-off state of each sub-electrode, the effective light-emitting area of each sub-pixel is dynamically adjusted, thereby solving the defect that the power consumption proportion of a blue light pixel is excessively high in a low brightness scenario, and effectively solving the problem of light-emitting area redundancy in the scenario.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor technology, specifically relating to pixel units, display panels, and their control systems and methods. Background Technology

[0002] In existing silicon-based OLED (OLED on Silicon) microdisplay technology, each color sub-pixel has only one anode structure, and the corresponding anode structure has a fixed aperture ratio, meaning that the effective light-emitting area is fixed regardless of the display brightness.

[0003] For example, in low-brightness (0-300 nit) design applications, for a single-layer emitting layer combined with a color filter (Single white light + CF) scheme, due to the low efficiency of blue light materials, a larger aperture ratio (e.g., R:G:B=13%:13%:26%) is usually required for blue light sub-pixels to balance the white field brightness. As a result, the power consumption ratio of blue light pixels is abnormally high.

[0004] For example, in a dual-layer light-emitting layer combined with a color filter (Tandem white light + CF), the RGB aperture ratio is usually the same (e.g., 18%). However, at low brightness, the excessively large effective light-emitting area becomes redundant, resulting in low carrier utilization. Furthermore, in the dark, the reflected light from the non-light-emitting area reduces the display contrast.

[0005] As shown above, both solutions suffer from efficiency imbalances and power consumption issues. Summary of the Invention

[0006] The purpose of this invention is to provide a pixel unit, a display panel, and a control system and method thereof to solve the technical problem of efficiency imbalance and power consumption in low-brightness application scenarios caused by the inability to dynamically adjust the effective light-emitting area of ​​each color sub-pixel.

[0007] The pixel unit includes an anode, including sub-anodes corresponding to different color sub-pixels, and the sub-anode corresponding to each color pixel includes at least two mutually isolated sub-electrodes; A driving circuit is used to independently control the on / off state of each sub-electrode in order to dynamically adjust the effective light-emitting area of ​​each sub-pixel.

[0008] The present invention also provides a display panel, including a driving chip and pixel units arranged in an array as described above. The driving chip includes a control unit and the driving circuit arranged in an array. The control unit is used to control the on or off state of multiple switching elements in the driving circuit according to the target brightness of the display panel and a preset mapping relationship between brightness and aperture ratio of each color pixel area, so as to dynamically adjust the effective light-emitting area of ​​each pixel unit.

[0009] The present invention also provides a control system for regulating the display panel as described above, the control system comprising: The identification module is used to call the first preset mapping table or the second preset mapping table according to the type of the display panel; The detection module is used to collect the real-time brightness of the display panel; The algorithm module is used to receive the real-time brightness of the display panel collected by the detection module, and to match the real-time brightness with a preset brightness range in the called mapping table to determine the preset aperture ratio range; The control module is used to generate on or off instructions for switching elements according to a predetermined preset aperture ratio range. The instructions control the on or off of each switching element in each pixel unit through a gate line.

[0010] The present invention also provides a control method for the display panel as described above, the display panel comprising an array of pixel units, each color sub-pixel of each pixel unit having at least two mutually isolated sub-electrodes, each sub-electrode being independently controlled by a corresponding switching element; the control method comprising the following steps: The first or second preset mapping table is invoked based on the type of the display panel; The panel brightness is collected at a preset frequency to eliminate noise interference and obtain a stable real-time brightness value. The corresponding preset aperture ratio range is determined by calling the first preset mapping table or the second preset mapping table based on the real-time brightness value; Based on the determined preset aperture ratio range, a switch element turn-on or turn-off command is generated and sent to the switch array of each sub-pixel. The gate line controls the turn-on or turn-off of each switch element in each pixel unit.

[0011] The technical advantages of this invention are as follows: This invention divides the sub-anode of each sub-pixel into several independently controlled sub-electrodes. By independently controlling the on / off state of each sub-electrode, the effective light-emitting area of ​​each sub-pixel can be dynamically adjusted. In low-brightness scenarios, by dynamically reducing the effective light-emitting area under low brightness, the carrier injection efficiency and utilization rate are improved, significantly reducing the overall display power consumption. For single-layer white light devices, this invention can solve the defect of excessively high power consumption of blue light pixels in this case; while for multi-layer white light devices, this invention can effectively solve the problem of redundant light-emitting area in this case. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the sub-electrode partitioning of a sub-pixel in a pixel unit according to Embodiment 1 of the present invention; Figure 2 This is a schematic diagram of the sub-electrode partitioning of a sub-pixel in a pixel unit according to Embodiment 2 of the present invention; Figure 3This is a cross-sectional schematic diagram of the blue sub-pixel in the pixel unit of Embodiment 1 of the present invention; Figure 4 This is a schematic diagram of the switching array circuit corresponding to the blue sub-pixel in the pixel unit of Embodiment 1 of the present invention; Figure 5 This is a flowchart illustrating the control method for the display panel according to Embodiment 1 of the present invention. Detailed Implementation

[0013] The following detailed description of the embodiments, with reference to the accompanying drawings, will further illustrate the specific implementation of the present invention, in order to help those skilled in the art to have a more complete, accurate, and in-depth understanding of the inventive concept and technical solution of the present invention.

[0014] This invention addresses the issues of efficiency imbalance, significant color shift, and driving redundancy by controlling the anode structure and effective light-emitting area, thereby effectively adjusting the effective light-emitting area of ​​each color sub-pixel based on real-time display brightness. The invention provides a pixel unit comprising an anode, sub-anodes corresponding to different color sub-pixels, and each sub-pixel comprising at least two mutually isolated sub-electrodes. A driving circuit is used to independently control the on / off state of each sub-electrode in order to dynamically adjust the effective light-emitting area of ​​each sub-pixel.

[0015] Traditional silicon-based OLEDs use a CMOS constant current source to drive each pixel, controlling brightness by adjusting the current. Under low brightness requirements, the fixed emitting area forces the driving circuit to operate at extremely low current levels. At this point, non-ideal factors such as transistor subthreshold characteristics and OLED turn-on voltage become more pronounced, leading to low power efficiency and energy waste.

[0016] In this embodiment, the maximum effective light-emitting area (total aperture ratio) of each sub-pixel is equal to the sum of the effective light-emitting areas of each sub-electrode. Therefore, by independently controlling the on / off state of each sub-electrode, the effective light-emitting area of ​​each sub-pixel can be dynamically adjusted. In low-brightness (0-300nit) application scenarios, the effective light-emitting area of ​​the sub-pixel can be reduced by turning off some sub-electrodes, thereby reducing the overall display power consumption. This also reduces electrode reflection in non-light-emitting areas, improving display contrast and the "integrated black" effect.

[0017] The sub-electrodes are isolated from each other by an insulating layer, the insulation resistance of which is ≥10 Ω. 12 Ω. Optionally, the insulating layer is made of silicon dioxide, and the number of independent sub-electrodes ranges from 2 to 5.

[0018] In one embodiment, the sub-electrodes are isolated by a 50nm thick silicon dioxide (SiO2) insulating layer, fabricated using a PECVD process, to prevent leakage and crosstalk between the sub-electrodes. Optionally, the driving circuit is integrated into the silicon substrate and includes a pixel driving circuit and a switch array. The switch array includes multiple parallel and independently configured switching elements. The output terminal of the pixel driving circuit is electrically connected to the first electrode of each of the switching elements; each sub-electrode is electrically connected to the second electrode of one of the switching elements.

[0019] In this embodiment, each sub-pixel has at least two sub-electrodes, and each sub-electrode has an independent switching element, realizing true independent control and providing a hardware foundation for dynamic aperture ratio adjustment. The switching array and pixel driving circuit are both integrated on the silicon substrate, which can be fabricated using standard CMOS processes, is highly compatible with existing silicon-based OLED mass production lines, and increases cost only slightly.

[0020] Optionally, the different color subpixels include red subpixels, green subpixels, and blue subpixels.

[0021] In this embodiment, different color subpixels may include common RGB values ​​to facilitate applicability to most products.

[0022] Optionally, the different color subpixels may further include white subpixels in RGBW technology and cyan subpixels in RGBC technology.

[0023] Optionally, the light-emitting layer of the pixel unit is a single layer; The total aperture ratio of both the red and green sub-pixels is not less than 12% and not more than 20%. The total aperture ratio of the blue sub-pixels is not less than 18% and not greater than 39%.

[0024] A single-layer emitting layer constitutes a Single White Light + CF (Cryogenic Filter) scheme. In this embodiment, to address the inherent drawback of the low efficiency of blue light materials in the Single White Light + CF scheme, a larger total aperture ratio is assigned to the blue light to balance the white field brightness. The aforementioned range of total aperture ratio balances the brightness output capability at high brightness and the adjustment space at low brightness, representing a balanced design; it enables optimal matching between the effective emitting area and current density at low brightness, reducing overall power consumption by more than 30%.

[0025] Optionally, the sub-anodes corresponding to the red sub-pixel and the green sub-pixel each include two sub-electrodes; and the corresponding pixel aperture ratios are both not less than 4% and not greater than 16%. The sub-anode corresponding to the blue sub-pixel includes three sub-electrodes, and the corresponding pixel aperture ratio is not less than 5% and not greater than 17%.

[0026] In this embodiment, at least two sub-electrodes are provided for red and green sub-pixels to adjust the aperture ratio, and at least three sub-electrodes are provided for blue to adjust the aperture ratio, with the latter offering finer adjustment granularity. The blue sub-pixels have the most partitions, reflecting their highest power consumption, thus providing the most flexible control capabilities. The aperture ratio range of each sub-electrode is moderate, avoiding excessively large adjustment steps due to an overly large individual sub-electrode area, and also avoiding excessively small areas that increase manufacturing complexity.

[0027] Optionally, the plurality of parallel-arranged switching elements are seven; the switching elements are field-effect transistors; The gates of the two field-effect transistors electrically connected to the two sub-electrodes of the red sub-pixel are electrically connected to the first gate line; The gates of the two field-effect transistors electrically connected to the two sub-electrodes of the green sub-pixel are electrically connected to the second gate line; The gates of the three field-effect transistors electrically connected to the three sub-electrodes of the blue sub-pixel are electrically connected to the third gate line.

[0028] All switches for subpixels of the same color are controlled by the same gate line, ensuring synchronized on / off and avoiding visual unevenness caused by partial illumination within the same color. Only three gate lines are required, simplifying the control logic and reducing the complexity of wiring and driver chip design. The seven switches correspond to a partitioned layout of the sub-electrodes, matching the sub-electrode design of a single-layer light-emitting layer.

[0029] Optionally, the light-emitting layer of the pixel unit is double-layered; The total aperture ratio of the red sub-pixel, the green sub-pixel, and the blue sub-pixel is not less than 12% and not greater than 26%.

[0030] The luminescent layer is a double-layer scheme, namely the Tandem white light + CF scheme. In this embodiment, taking advantage of the consistent RGB aperture ratio in the Tandem white light + CF scheme, a balanced aperture ratio range for each color is given. Since the luminous efficiency of the double-layer device is higher than that of the single-layer device, the upper limit of the total aperture ratio (26%) is lower than that of the single-layer blue (39%), and the parameters are reasonable. Furthermore, the effective luminescent area can be dynamically reduced at low brightness by using sub-electrodes, thus solving the problem of redundant luminescent area in stacked devices at low brightness.

[0031] Optionally, the sub-anodes corresponding to the red sub-pixel, the green sub-pixel, and the blue sub-pixel each include three sub-electrodes; and the corresponding pixel aperture ratios are all not less than 4% and not greater than 9%.

[0032] The red, green, and blue colors are all divided into three equal parts, which can achieve three levels of aperture ratio. The adjustment is symmetrical and the algorithm is unified. This adjustment is matched with the basic design of consistent RGB aperture ratio of dual-layer devices, ensuring the symmetry of the design.

[0033] Optionally, the plurality of parallel-arranged switching elements may be nine.

[0034] Each color subpixel has three independently controlled sub-electrodes, all with equal color adjustment capabilities and symmetrical control algorithms, reducing the design complexity of the driver chip. The switching element settings correspond to the partitioned layout of the sub-electrodes, matching the sub-electrode design of the dual-layer light-emitting layer.

[0035] Specifically, the pixel unit provided by this invention is fabricated through the following process steps: fabrication of a silicon-based CMOS driving array on a silicon substrate, integration of an NMOS switch array, integration of a PD sensor, anode partitioning photolithography and etching, deposition of a SiO2 insulating layer, OLED light-emitting layer evaporation (Single / Tandem white light), cathode evaporation, thin-film encapsulation (TFE), fabrication of a color filter, and dicing and testing. The driving circuit and switch array are integrated during the fabrication process.

[0036] In the sub-anode fabrication process, the ITO (indium tin oxide) anode of each RGB sub-pixel is patterned into multiple physically independent sub-electrodes through photolithography and etching processes.

[0037] All hardware structures of the pixel unit (partition electrodes, MOS switches, PD sensors) can be fabricated using standard CMOS processes, making it highly compatible with existing silicon-based OLED mass production lines with limited cost increases.

[0038] This embodiment also provides a display panel, including a driving chip and pixel units arranged in an array as described above. The driving chip includes a control unit and the driving circuit arranged in an array. The control unit is used to control the on or off state of multiple switching elements in the driving circuit according to the target brightness of the display panel and a preset mapping relationship between brightness and aperture ratio of each color pixel area, so as to dynamically adjust the effective light-emitting area of ​​each pixel unit.

[0039] In this embodiment, a novel display panel is provided based on the innovation of a single pixel unit. The control unit realizes intelligent control based on a preset mapping table. The preset mapping table introduces mapping relationships for control. The control strategy can be pre-configured and optimized, and the optimal aperture ratio is automatically matched for different brightness ranges.

[0040] Optionally, when the light-emitting layer of the pixel unit is a single layer, the control unit stores a first preset mapping table that is relatively set with preset brightness and preset aperture ratio; the first preset mapping table includes a first range, a second range and a third range; The first range includes a preset brightness range of not less than 0 nits and less than 50 nits, corresponding to a preset aperture ratio range of: the aperture ratio of both red and green sub-pixels is not less than 4% and not greater than 16%, and the aperture ratio of both blue sub-pixels is not less than 5% and not greater than 17%. The second range includes a preset brightness range of not less than 50 nits and less than 200 nits, corresponding to a preset aperture ratio range of: the aperture ratio of both red and green sub-pixels is not less than 4% and not greater than 16%, and the aperture ratio of both blue sub-pixels is not less than 5% and not greater than 17%. The third range includes a preset brightness range of not less than 200 nits and not more than 300 nits, corresponding to a preset aperture ratio range of: the aperture ratio of red sub-pixels and green sub-pixels is not less than 12% and not more than 20%, and the aperture ratio of blue sub-pixels is not less than 18% and not more than 39%.

[0041] This embodiment is adapted to situations where the emitting layer of the pixel unit is a single layer. The low brightness range of 0-300 nits is subdivided into three levels, with reasonable adjustment granularity, balancing power consumption optimization and smooth brightness transition. In the first and second levels, the lower limit of the red-green aperture ratio is as low as 4%, and the blue aperture ratio is as low as 5%, ensuring maximum carrier utilization at extremely low brightness. The third level restores a larger aperture ratio close to that of traditional designs, guaranteeing brightness output capability during high-brightness periods.

[0042] Optionally, when the light-emitting layer of the pixel unit is double-layered, the control unit stores a second preset mapping table formed by a preset brightness and a preset aperture ratio, the second preset mapping table including a fourth range, a fifth range and a sixth range; The fourth range includes a preset brightness range of not less than 0 nits and less than 50 nits, corresponding to a preset aperture ratio range of: the aperture ratio of sub-pixels for red, green and blue colors is not less than 4% and not greater than 9%; The fifth range includes a preset brightness range of not less than 50 nits and less than 200 nits, corresponding to a preset aperture ratio range of not less than 8% and not more than 18% for sub-pixels of red, green and blue colors; The sixth range includes a preset brightness range of not less than 200 nits and not more than 300 nits, corresponding to a preset aperture ratio range of not less than 12% and not more than 26% for the sub-pixels of red, green and blue colors.

[0043] This embodiment is adapted to cases where the pixel unit has a dual-layer emitting layer. The low brightness range of 0-300 nits is also subdivided into three levels. The aperture ratios for red, green, and blue light remain consistent across all levels, conforming to the symmetrical design of the Tandem white light + CF scheme. The aperture ratio in the first level is as low as 4%~9%, minimizing low-brightness power consumption and reflectivity, with reflectivity reduced to below 1.2%. Compared to a single-layer mapping table, the overall aperture ratio is higher within the same brightness range, consistent with the higher luminous efficiency of dual-layer devices.

[0044] Optionally, the driving chip further includes a photoelectric sensor for real-time acquisition of brightness data of the display panel and feedback to the control unit to assist the control unit in adjusting the brightness.

[0045] This embodiment uses the brightness data of the display panel to assist the control unit in adjusting the brightness, forming a closed-loop feedback mechanism, which can achieve real-time brightness monitoring without relying on external testing equipment.

[0046] This embodiment also provides a control system for regulating the display panel as described above, the control system comprising: The identification module is used to call the first preset mapping table or the second preset mapping table according to the type of the display panel; The detection module is used to collect the real-time brightness of the display panel; The algorithm module is used to receive the real-time brightness of the display panel collected by the detection module, and to match the real-time brightness with a preset brightness range in the called mapping table to determine the preset aperture ratio range; The control module is used to generate on or off instructions for switching elements according to a predetermined preset aperture ratio range. The instructions control the on or off of each switching element in each pixel unit through a gate line.

[0047] In this embodiment, the control system automatically identifies single-layer / double-layer device types and calls the corresponding mapping table through the identification module, making one system compatible with both architectures. The various modules work together to form a closed-loop control scheme from detection and algorithm to control, achieving full-chain automation from brightness acquisition to command issuance. Control commands are directly transmitted through the grid lines, utilizing the existing display driver architecture.

[0048] Optionally, the control system may also include: The color shift compensation module is used to simultaneously fine-tune the driving current of the blue light pixel when the aperture ratio is switched, in order to compensate for the color shift value in the low brightness range. The reflectivity monitoring module is used to monitor the panel's dark reflectivity in real time, and when the reflectivity exceeds a set threshold, the corresponding preset aperture ratio range is lowered by one level.

[0049] The color shift compensation module includes a current fine-tuning module integrated into the CMOS driver chip, an adder circuit, and color shift calculation logic. Its workflow is as follows: the PD sensor acquires the RGB three-color spectrum in real time; the driver chip calculates the current color shift value ΔE; and based on the calculation result, it is output to the constant current source input of the blue light pixel via a DAC converter.

[0050] In this embodiment, on the one hand, the color shift compensation module compensates for the color shift that may be caused by the aperture ratio switching, especially by synchronously fine-tuning the blue light current, thereby limiting the degree of color shift and meeting the professional-grade color accuracy requirements; on the other hand, the reflectivity monitoring module monitors the dark reflectivity in real time, and automatically lowers the aperture ratio by one level when the reflectivity exceeds the standard, further optimizing the "integrated black" effect; the two modules complement each other, taking into account both color accuracy and image quality contrast.

[0051] This embodiment also provides a control method for a display panel, the display panel including pixel units arranged in an array, each color sub-pixel of each pixel unit having at least two mutually isolated sub-electrodes, each sub-electrode being independently controlled by a corresponding switching element; the control method includes the following steps: The first or second preset mapping table is invoked based on the type of the display panel; The panel brightness is collected at a preset frequency to eliminate noise interference and obtain a stable real-time brightness value. The corresponding preset aperture ratio range is determined by calling the first preset mapping table or the second preset mapping table based on the real-time brightness value; Based on the determined preset aperture ratio range, a switch element turn-on or turn-off command is generated and sent to the switch array of each sub-pixel. The gate line controls the turn-on or turn-off of each switch element in each pixel unit.

[0052] This embodiment achieves sub-electrode control of the display panel under low light conditions by sequentially calling the mapping table, collecting brightness, determining aperture ratio, and generating and issuing commands through the above control method. At the same time, it can also eliminate noise interference to ensure the accuracy of brightness values ​​and avoid frequent or erroneous switching caused by noise. The control path from switch array to grid line control is also simple and efficient, enabling high-speed switching.

[0053] Optionally, the control method of the display panel further includes: while switching the aperture ratio, acquiring the RGB three-color spectrum of the pixel unit in real time, calculating the current color deviation value, determining the direction and amplitude of color deviation compensation, generating a fine-tuning instruction for the driving current of the blue sub-pixel, and outputting it to the constant current source input terminal of the blue sub-pixel after conversion by a DAC converter.

[0054] In this embodiment, compensation and switching are performed simultaneously, avoiding the transient color shift that may occur if compensation is performed after switching. The RGB three-color spectrum is acquired in real time, and the color shift value is calculated in real time, effectively improving the real-time performance of accuracy compensation. The fine-tuning command is output to the constant current source input terminal via DAC, directly acting on the light source, resulting in a fast response speed.

[0055] Optionally, the control method for the display panel further includes: after switching the aperture ratio, performing reflectivity detection; if the reflectivity is greater than a set threshold, then lowering the corresponding preset aperture ratio range by one level and re-executing the aperture ratio switching.

[0056] In this embodiment, after the aperture ratio is switched, a closed-loop control design is formed that sequentially switches, detects, and corrects, which can be used to handle transient disturbances. Each re-execution of the switch ensures that the correction always takes effect, improving the robustness of the system. Adjusting only one level down during adjustment avoids over-adjustment.

[0057] Optionally, the control method for the display panel further includes: after the display panel enters a steady-state display, continuously monitoring the reflectivity; if the reflectivity is greater than a set threshold three times in a row, then the corresponding preset aperture ratio range is lowered by one level, and aperture ratio switching is performed.

[0058] In this embodiment, the use of three consecutive judgment conditions effectively avoids false triggering caused by single, occasional fluctuations. This control method can cope with long-term drift, and continuous monitoring after steady-state operation demonstrates the system's adaptive capability during long-term operation, ensuring image quality consistency. When parameters are stable, the current settings are maintained to reduce system overhead and balance performance and power consumption.

[0059] For the Single white light + CF solution and the Tandem white light + CF solution, the present invention provides the following specific embodiments: Example 1 Single white light + CF solution: such as Figure 1 , Figure 3 As shown in Embodiment 1, a pixel unit is provided, wherein the light-emitting layer of the pixel unit is a single layer. The pixel unit includes red sub-pixels, green sub-pixels, and blue sub-pixels. The sub-anodes corresponding to different colored sub-pixels include two or three sub-electrodes, and the sub-electrodes are isolated from each other by a 50nm thick silicon dioxide (SiO2) insulating layer.

[0060] Specifically, the total aperture ratios of each sub-pixel are R: 13%, G: 13%, and B: 26%, where R, G, and B represent the red, green, and blue sub-pixels, respectively. Specifically, in the sub-anodes corresponding to the red and green sub-pixels, one independent sub-electrode has an aperture ratio of 5%, and the other independent sub-electrode has an aperture ratio of 8%. In the sub-anodes corresponding to the blue sub-pixels, the two independent sub-electrodes have an aperture ratio of 10%, and the remaining sub-electrode has an aperture ratio of 6%. Thus, both the red and green sub-pixels can be independently controlled by the on / off state of their sub-electrodes, dynamically adjusting their effective light-emitting area to achieve aperture ratios of 5%, 8%, and 13% for the corresponding sub-pixels. Similarly, the blue sub-pixels can dynamically adjust their effective light-emitting area in a similar manner, achieving aperture ratios of 10%, 16%, and 26% for the corresponding sub-pixels.

[0061] The pixel unit also includes a driving circuit for independently controlling the on / off state of each sub-electrode to dynamically adjust the effective light-emitting area of ​​each sub-pixel. The driving circuit is integrated into the silicon substrate and includes a pixel driving circuit and a switch array. The switch array includes multiple parallel and independently configured switching elements, which are MOS switches. The switch array also includes a circuit for generating switching control signals for the sub-electrodes.

[0062] This embodiment can significantly reduce the reflection of the high proportion of blue light electrodes and solve the problem of excessive power consumption of blue light pixels in the Single white light device by adjusting the effective light-emitting area of ​​each sub-pixel in the Single white light device.

[0063] The driving circuit uses a standard CMOS process to fabricate a driving backplane on a single-crystal silicon substrate. The pixel driving circuit uses a constant current driving circuit, including a compensation structure of 2T1C or more transistors to provide a stable driving current I_out; it also includes a storage capacitor Cst to keep the gate voltage stable.

[0064] In the pixel driving circuit, the MOS switch specifically uses NMOS transistors. Their drains (D) are connected in parallel to the current output node I_out of the pixel driving circuit, their sources (S) are connected to the corresponding sub-electrode, and their gates (G) are connected to an independent switch control signal. The device parameters of the switching element are: threshold voltage Vth = 0.8V, switch response time ≤ 0.2ms, and fabricated using the same process as the CMOS driving circuit. In terms of control logic, in the above switch array, all NMOS transistors of each sub-pixel are selected by the scan line (Gate line) of the same pixel to ensure synchronous response. The entire aperture ratio switching process can be completed within 1ms, avoiding visual stuttering or flickering. The switch array circuit corresponding to the sub-electrode in the blue sub-pixel is shown below. Figure 4 As shown.

[0065] The aperture ratio switching refers to the process by which the instruction controls the switching elements in each pixel unit to be turned on or off via the gate line.

[0066] In this embodiment, where the light-emitting layer of the pixel unit is a single layer, a display panel is also provided. The display panel includes a driving chip and pixel units arranged in an array as described in Embodiment 1. The driving chip includes a control unit and the driving circuit arranged in an array. The control unit is used to control the on or off state of multiple switching elements in the driving circuit according to the target brightness of the display panel and based on a preset mapping relationship between brightness and aperture ratio of each color pixel area, so as to dynamically adjust the effective light-emitting area of ​​each pixel unit.

[0067] The driving chip also includes a photoelectric sensor for real-time acquisition of brightness data of the display panel and feedback to the control unit to assist the control unit in adjusting the brightness.

[0068] In this embodiment, the photoelectric sensor is an integrated photodiode (PD) sensor, which enables the detection of brightness. The spectral response range is 400-700nm in the visible light band, the sampling frequency is 120Hz, and the brightness data is fed back to the driver chip using an I²C digital interface.

[0069] This embodiment also provides a control system for regulating the display panel as described in Embodiment 1, the control system comprising: The identification module is used to call the first preset mapping table according to the type of the display panel; The detection module is used to collect the real-time brightness of the display panel; The algorithm module is used to receive the real-time brightness of the display panel collected by the detection module, and to match the real-time brightness with a preset brightness range in the called mapping table to determine the preset aperture ratio range; The control module is used to generate on or off instructions for switching elements according to a determined preset aperture ratio range. The instructions control the on or off of each switching element in each pixel unit through a gate line. The color shift compensation module is used to simultaneously fine-tune the driving current of the blue light pixel when the aperture ratio is switched, in order to compensate for the color shift value in the low brightness range. The reflectivity monitoring module is used to monitor the panel's dark reflectivity in real time, and when the reflectivity exceeds a set threshold, the corresponding preset aperture ratio range is lowered by one level.

[0070] In this embodiment, the color shift compensation module includes a current fine-tuning module integrated into the CMOS driver chip, an addition circuit, and color shift calculation logic. Its workflow is as follows: the PD sensor acquires the RGB three-color spectrum in real time; the driver chip calculates the current color shift value ΔE; and based on the calculation result, it is output to the constant current source input terminal of the blue light pixel via a DAC converter.

[0071] This embodiment also provides a control method for a display panel as described in Embodiment 1. The display panel includes pixel units arranged in an array, and each color sub-pixel of each pixel unit has at least two mutually isolated sub-electrodes, each sub-electrode being independently controlled by a corresponding switching element; Figure 5 As shown, the control method includes the following steps: Step 1: Call the first preset mapping table according to the type of display panel.

[0072] In this embodiment, this step is performed during system initialization. Upon power-up, the device type is identified as a Single white light device with a single-layer light-emitting layer by the configuration register, and then the corresponding first preset mapping table is loaded into the cache.

[0073] In the first preset mapping table, the specific correspondence can be as follows: First setting: Preset brightness range: [0, 50], aperture ratio of R / G / B sub-pixels: 5% / 5% / 10%; Second setting: Preset brightness range: [50, 200], R / G / B sub-pixel aperture ratio: 8% / 8% / 16%; Third setting: Preset brightness range: [200, 300], aperture ratio of R / G / B sub-pixels: 13% / 13% / 26%.

[0074] The regulatory objectives for the above-mentioned correspondence are as follows: First priority: Maximize carrier utilization and minimize power consumption; Second level: Balance luminous efficiency and color purity; Third level: Matches the basic design to ensure uniform brightness.

[0075] Step 2: Collect panel brightness at a preset frequency to eliminate noise interference and obtain a stable real-time brightness value.

[0076] In this embodiment, the integrated photodiode (PD) sensor collects panel brightness at a frequency of 120Hz. Then, Gaussian filtering is applied to the eight consecutive frames of data collected to eliminate noise interference, resulting in a stable real-time brightness value L_real.

[0077] Step 3: Determine the corresponding preset aperture ratio range from the first preset mapping table based on the real-time brightness value.

[0078] This step determines the level corresponding to the real-time brightness value based on the real-time brightness value L_real measured in step 2, and thereby determines the aperture ratio of the R / G / B sub-pixels.

[0079] Step 4: Generate on or off instructions for the switching elements according to the determined preset aperture ratio range, and send them to the switching array of each sub-pixel. Control the on or off of each switching element in each pixel unit through the gate line.

[0080] In this embodiment, the response time for switching the aperture ratio of the full screen or a local area is ≤1ms.

[0081] Optionally, the control method further includes: while switching the aperture ratio, acquiring the RGB three-color spectrum of the pixel unit in real time, calculating the current color deviation value, determining the direction and magnitude of color deviation compensation, generating a fine-tuning instruction for the driving current of the blue sub-pixel, and outputting it to the constant current source input terminal of the blue sub-pixel after conversion by a DAC converter.

[0082] In response to the high blue light aperture ratio of Single white light devices, this embodiment simultaneously fine-tunes the driving current of the blue light pixel (adjustment range ±3%) when switching aperture ratios to ensure that the color deviation value ΔE in the low brightness range is less than 1.5.

[0083] The color deviation value ΔE is calculated according to the CIE 1976 Lab color space, as follows: Where L1, a1, and b1 are the Lab values ​​of the target color, corresponding to lightness, red-green axis, and yellow-blue axis, respectively; L2, a2, and b2 are the Lab values ​​of the measured actual displayed color, corresponding to lightness, red-green axis, and yellow-blue axis, respectively.

[0084] The luminous efficiency of OLED materials exhibits a non-linear relationship with current density, especially at extremely low current densities, where the efficiency decay curves of the RGB materials show significant differences. A fixed aperture ratio design cannot compensate for this efficiency difference caused by variations in driving conditions, resulting in noticeable color shifts (increased ΔE value) in the displayed image at low brightness, thus affecting color accuracy.

[0085] This invention combines a control method with a color deviation compensation mechanism to control the color difference value ΔE within 1.5, thus meeting the color accuracy requirements of professional-grade display devices.

[0086] The control method described in Example 1 further includes: after switching the aperture ratio, performing reflectivity detection; if the reflectivity is greater than a set threshold, then lowering the corresponding preset aperture ratio range by one level and re-executing the aperture ratio switching. The adjustment range and response speed of this mode correspond to the correction of transient interference. After the display panel enters steady-state display, the reflectivity is continuously monitored; if it is greater than the set threshold three times consecutively, then lowering the corresponding preset aperture ratio range by one level and executing the aperture ratio switching. The adjustment range and response speed of this mode correspond to the correction of long-term drift.

[0087] An example of the control method described in Example 1 is as follows: The PD sensor detects L_real = 30 nit, matching the [0, 50 nit] range, i.e., the first setting, with corresponding sub-electrode aperture ratios of: R = 5%, G = 5%, B = 10%. Control commands are generated accordingly: for R / G sub-pixels, turn on one sub-electrode with an aperture ratio of 5% and turn off one sub-electrode with an aperture ratio of 8%; for B sub-pixels, turn on one sub-electrode with an aperture ratio of 6% and turn off two sub-electrodes with an aperture ratio of 10%. Then, based on the above algorithm, the color shift value is calculated, thereby determining the compensation scheme: synchronously fine-tuning the blue light current by -2% to compensate for aperture ratio changes. If the detected reflectance is not greater than the set threshold, no further aperture ratio switching adjustment is performed.

[0088] After adjusting the effective light-emitting area, the above example, compared with the existing traditional single white light device, reduces power consumption by about 35% when the real-time brightness value is reduced to 30 nits, and keeps the color deviation value ΔE <1.3.

[0089] Example 2 Tandem white light + CF solution: such as Figure 2 As shown in Example 2, a pixel unit is provided, wherein the light-emitting layer of the pixel unit is double-layered. The pixel unit includes a red sub-pixel, a green sub-pixel, and a blue sub-pixel. The sub-anodes corresponding to the different colored sub-pixels include at least three sub-electrodes, and the sub-electrodes are isolated from each other by a 50nm thick silicon dioxide (SiO2) insulating layer.

[0090] Specifically, the total aperture ratios of each sub-pixel are R: 18%, G: 18%, and B: 18%, respectively, where R, G, and B represent the red, green, and blue sub-pixels, respectively; that is, the total aperture ratio of each color sub-pixel is 18%. For any color sub-pixel, the aperture ratio of the three sub-electrodes is 6%. The effective light-emitting area of ​​the color sub-pixel is independently controlled by the on / off state of the sub-electrodes, resulting in three aperture ratios of 6%, 12%, and 18%.

[0091] The pixel unit also includes a driving circuit for independently controlling the on / off state of each sub-electrode to dynamically adjust the effective light-emitting area of ​​each sub-pixel. The driving circuit is integrated into the silicon substrate and includes a pixel driving circuit and a switch array. The switch array includes multiple parallel and independently configured switching elements, which are MOS switches. The switch array also includes a circuit for generating switching control signals for the sub-electrodes.

[0092] This embodiment solves the problem of redundant effective light-emitting areas of sub-pixels of different colors in the Tandem white light device by adjusting the effective light-emitting area of ​​each sub-pixel.

[0093] In this embodiment, the structure and device parameters of the driving circuit are the same as in Embodiment 1, the difference being the number of switching elements corresponding to the sub-electrodes.

[0094] With the pixel unit having a double-layer light-emitting layer, this embodiment also provides a display panel. The display panel includes a driving chip and pixel units arranged in an array as described in Embodiment 2. The driving chip includes a control unit and the driving circuit arranged in an array. The control unit is used to control the on or off state of multiple switching elements in the driving circuit according to the target brightness of the display panel and based on a preset mapping relationship between brightness and aperture ratio of each color pixel area, so as to dynamically adjust the effective light-emitting area of ​​each pixel unit.

[0095] The driver chip also includes a photoelectric sensor. In this embodiment, the type and parameters of the photoelectric sensor are the same as in Embodiment 1.

[0096] This embodiment also provides a control system for regulating the display panel as described in Embodiment 2, the control system comprising: The identification module is used to call the second preset mapping table according to the type of the display panel; The detection module is used to collect the real-time brightness of the display panel; The algorithm module is used to receive the real-time brightness of the display panel collected by the detection module, and to match the real-time brightness with a preset brightness range in the called mapping table to determine the preset aperture ratio range; The control module is used to generate on or off instructions for switching elements according to a determined preset aperture ratio range. The instructions control the on or off of each switching element in each pixel unit through a gate line. The reflectivity monitoring module is used to monitor the panel's dark reflectivity in real time, and when the reflectivity exceeds a set threshold, the corresponding preset aperture ratio range is lowered by one level.

[0097] Compared to Example 1, this example does not include a color shift compensation module.

[0098] This embodiment also provides a control method for a display panel as described in Embodiment 2. The display panel includes pixel units arranged in an array, and each color sub-pixel of each pixel unit has at least two mutually isolated sub-electrodes, each sub-electrode being independently controlled by a corresponding switching element; the control method includes the following steps: Step 1: Call the second preset mapping table according to the type of display panel.

[0099] In this embodiment, this step is performed during system initialization. Upon power-up, the device type is identified as a Tandem white light device with a dual-layer light-emitting layer by the configuration register, and then the corresponding second preset mapping table is loaded into the cache.

[0100] The specific correspondences in the second preset mapping table are as follows: First setting: Preset brightness range: [0, 50], aperture ratio of R / G / B sub-pixels: 6% / 6% / 6%; Second setting: Preset brightness range: [50, 200], R / G / B sub-pixel aperture ratio: 12% / 12% / 12%; Third setting: Preset brightness range: [200, 300], aperture ratio of R / G / B sub-pixels: 18% / 18% / 18%.

[0101] The regulatory objectives for the above-mentioned correspondence are as follows: First priority: Maximize carrier utilization and minimize power consumption; Second level: Balance luminous efficiency and color purity; Third level: Matches the basic design to ensure uniform brightness.

[0102] Step 2: Collect panel brightness at a preset frequency to eliminate noise interference and obtain a stable real-time brightness value L_real.

[0103] Step 3: Determine the corresponding preset aperture ratio range from the second preset mapping table based on the real-time brightness value.

[0104] This step determines the level corresponding to the real-time brightness value based on the real-time brightness value L_real measured in step 2, and thereby determines the aperture ratio of the R / G / B sub-pixels.

[0105] Step 4: Generate on or off instructions for the switching elements according to the determined preset aperture ratio range, and send them to the switching array of each sub-pixel. Control the on or off of each switching element in each pixel unit through the gate line.

[0106] In this embodiment, the process of reflectivity detection by the control method is the same as in Embodiment 1.

[0107] An example of the control method described in Example 2 is as follows: The PD sensor detects L_real = 150 nit, matching the [50, 200 nit] range, i.e., the second setting, with corresponding sub-electrode aperture ratios of R = 12%, G = 12%, and B = 12%. A control command is then generated: for each color sub-pixel, two sub-electrodes with an aperture ratio of 6% are turned on, and one sub-electrode with an aperture ratio of 6% is turned off. If the detected reflectivity is not greater than a set threshold, no further aperture ratio adjustment is performed.

[0108] After adjusting the effective light-emitting area, the above example shows that, compared to existing traditional Tandem white light devices, power consumption is reduced by about 25% and reflectivity is reduced to 1.1% at a real-time brightness of 150 nits.

[0109] This invention can dynamically reduce the aperture ratio under low brightness, effectively reducing the dark reflectivity of the panel to below 1.2%, thereby achieving a purer black display effect and higher visual contrast.

[0110] Existing technological improvements primarily focus on the precise calibration and compensation of the driving current, such as improving the compensation circuitry of the internal driving transistors of the pixel, or performing digital gamma correction using external chips. However, these methods do not address the physical dimension of the "effective light-emitting area of ​​the pixel," failing to fully utilize the precise controllability of electrode patterns inherent in silicon-based CMOS processes. Especially in the low-brightness range, simply adjusting the current cannot fundamentally resolve the contradictions between efficiency, color shift, and reflectivity.

[0111] This invention, through innovative hardware design and intelligent control algorithms, achieves dynamic aperture ratio adjustment of silicon-based OLEDs in the low-brightness range, effectively solving the technical bottleneck of traditional fixed aperture ratio designs and providing an optimized solution for low-power micro-display applications such as AR glasses. Furthermore, this invention provides specific embodiments for both Single and Tandem white light device architectures, demonstrating strong versatility.

[0112] The present invention has been described above by way of example with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvements made using the inventive concept and technical solution of the present invention, or the direct application of the inventive concept and technical solution of the present invention to other occasions without modification, are all within the protection scope of the present invention.

Claims

1. A pixel unit, characterized in that, include: The anode includes sub-anodes corresponding to different color sub-pixels, and the sub-anode corresponding to each color pixel includes at least two mutually isolated sub-electrodes; A driving circuit is used to independently control the on / off state of each sub-electrode in order to dynamically adjust the effective light-emitting area of ​​each sub-pixel.

2. The pixel unit according to claim 1, characterized in that, The driving circuit is integrated in the silicon substrate and includes a pixel driving circuit and a switch array. The switch array includes multiple switch elements arranged in parallel and independently configured. The output terminal of the pixel driving circuit is electrically connected to the first pole of each of the switch elements. Each of the sub-electrodes is electrically connected to a corresponding second electrode of one of the switching elements.

3. The pixel unit according to claim 1, characterized in that, Different colored subpixels include red subpixels, green subpixels, and blue subpixels.

4. The pixel unit according to claim 3, characterized in that, The light-emitting layer of the pixel unit is a single layer; The total aperture ratio of both the red and green sub-pixels is not less than 12% and not greater than 20%. The total aperture ratio of the blue sub-pixels is not less than 18% and not greater than 39%.

5. The pixel unit according to claim 4, characterized in that, The sub-anodes corresponding to the red sub-pixel and the green sub-pixel each include two sub-electrodes; and the corresponding pixel aperture ratios are both not less than 4% and not greater than 16%. The sub-anode corresponding to the blue sub-pixel includes three sub-electrodes, and the corresponding pixel aperture ratio is not less than 5% and not greater than 17%.

6. The pixel unit according to claim 4 or 5, characterized in that, The plurality of parallel-arranged switching elements number seven; the switching elements are field-effect transistors; The gates of the two field-effect transistors electrically connected to the two sub-electrodes of the red sub-pixel are electrically connected to the first gate line; The gates of the two field-effect transistors electrically connected to the two sub-electrodes of the green sub-pixel are electrically connected to the second gate line; The gates of the three field-effect transistors electrically connected to the three sub-electrodes of the blue sub-pixel are electrically connected to the third gate line.

7. The pixel unit according to claim 3, characterized in that, The light-emitting layer of the pixel unit is double-layered; The total aperture ratio of the red sub-pixel, the green sub-pixel, and the blue sub-pixel is not less than 12% and not greater than 26%.

8. The pixel unit according to claim 7, characterized in that, The sub-anodes corresponding to the red sub-pixel, the green sub-pixel, and the blue sub-pixel each include three sub-electrodes; and the corresponding pixel aperture ratios are all not less than 4% and not greater than 9%.

9. The pixel unit according to claim 7 or 8, characterized in that, The number of parallel-arranged switching elements is nine.

10. A display panel, characterized in that, The pixel unit according to any one of claims 1-9 includes a driving chip and an array arrangement. The driving chip includes a control unit and the driving circuit arranged in the array. The control unit is used to control the on or off state of multiple switching elements in the driving circuit according to the target brightness of the display panel and a preset mapping relationship between brightness and aperture ratio of each color pixel area, so as to dynamically adjust the effective light-emitting area of ​​each pixel unit.

11. The display panel according to claim 10, characterized in that, When the light-emitting layer of the display panel is a single layer, the control unit stores a first preset mapping table that is relative to a preset brightness and a preset aperture ratio; the first preset mapping table includes a first range, a second range, and a third range; The first range includes a preset brightness range of not less than 0 nits and less than 50 nits, corresponding to a preset aperture ratio range of: the aperture ratio of both red and green sub-pixels is not less than 4% and not greater than 16%, and the aperture ratio of both blue sub-pixels is not less than 5% and not greater than 17%. The second range includes a preset brightness range of not less than 50 nits and less than 200 nits, corresponding to a preset aperture ratio range of: the aperture ratio of both red and green sub-pixels is not less than 4% and not greater than 16%, and the aperture ratio of both blue sub-pixels is not less than 5% and not greater than 17%. The third range includes a preset brightness range of not less than 200 nits and not more than 300 nits, corresponding to a preset aperture ratio range of: the aperture ratio of red sub-pixels and green sub-pixels is not less than 12% and not more than 20%, and the aperture ratio of blue sub-pixels is not less than 18% and not more than 39%.

12. The display panel according to claim 10, characterized in that, When the light-emitting layer of the display panel is double-layered, the control unit stores a second preset mapping table formed by preset brightness and preset aperture ratio. The second preset mapping table includes a fourth range, a fifth range and a sixth range. The fourth range includes a preset brightness range of not less than 0 nits and less than 50 nits, corresponding to a preset aperture ratio range of: the aperture ratio of sub-pixels for red, green and blue colors is not less than 4% and not greater than 9%; The fifth range includes a preset brightness range of not less than 50 nits and less than 200 nits, corresponding to a preset aperture ratio range of not less than 8% and not more than 18% for sub-pixels of red, green and blue colors; The sixth range includes a preset brightness range of not less than 200 nits and not more than 300 nits, corresponding to a preset aperture ratio range of not less than 12% and not more than 26% for the sub-pixels of red, green and blue colors.

13. The display panel according to any one of claims 10-12, characterized in that, The driving chip also includes a photoelectric sensor for real-time acquisition of brightness data of the display panel and feedback to the control unit to assist the control unit in adjusting the brightness.

14. A control system, characterized in that, The control system for regulating the display panel according to any one of claims 10-13 includes: The identification module is used to call the first preset mapping table or the second preset mapping table according to the type of the display panel; The detection module is used to collect the real-time brightness of the display panel; The algorithm module is used to receive the real-time brightness of the display panel collected by the detection module, and to match the real-time brightness with a preset brightness range in the called mapping table to determine the preset aperture ratio range; The control module is used to generate on or off instructions for switching elements according to a predetermined preset aperture ratio range. The instructions control the on or off of each switching element in each pixel unit through a gate line.

15. The control system according to claim 14, characterized in that, Also includes: The color shift compensation module is used to simultaneously fine-tune the driving current of the blue light pixel when the aperture ratio is switched, in order to compensate for the color shift value in the low brightness range. The reflectivity monitoring module is used to monitor the panel's dark reflectivity in real time, and when the reflectivity exceeds a set threshold, the corresponding preset aperture ratio range is lowered by one level.

16. A method for controlling a display panel, characterized in that, The display panel includes pixel units arranged in an array, and each sub-pixel of each color in the pixel unit has at least two mutually isolated sub-electrodes, each sub-electrode being independently controlled by a corresponding switching element; the control method includes the following steps: The first or second preset mapping table is invoked based on the type of the display panel; The panel brightness is collected at a preset frequency to eliminate noise interference and obtain a stable real-time brightness value. The corresponding preset aperture ratio range is determined by calling the first preset mapping table or the second preset mapping table based on the real-time brightness value; Based on the determined preset aperture ratio range, a switch element turn-on or turn-off command is generated and sent to the switch array of each sub-pixel. The gate line controls the turn-on or turn-off of each switch element in each pixel unit.

17. The control method for the display panel according to claim 16, characterized in that, Also includes: While switching the aperture ratio, the RGB three-color spectrum of the pixel unit is acquired in real time, the current color deviation value is calculated, the direction and magnitude of color deviation compensation are determined, and a fine-tuning instruction for the driving current of the blue sub-pixel is generated. After being converted by the DAC converter, the instruction is output to the constant current source input terminal of the blue sub-pixel.

18. The control method for the display panel according to claim 16, characterized in that, Also includes: After switching the aperture ratio, reflectivity is detected; if the reflectivity is greater than the set threshold, the corresponding preset aperture ratio range is lowered by one level, and the aperture ratio switching is performed again.

19. The control method for the display panel according to claim 16 or 18, characterized in that, Also includes: After the display panel enters a steady state, the reflectivity is continuously monitored. If the reflectivity is greater than the set threshold three times in a row, the corresponding preset aperture ratio range is lowered by one level, and the aperture ratio is switched.

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