27 patents in this list

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Micro-LED displays face critical challenges in achieving precise color control at the pixel level. Individual LED elements exhibit inherent variations in peak wavelength emission, with shifts of 2-3nm common across a single wafer, while maintaining consistent brightness requires careful management of different forward voltage requirements—typically 2.0V for red, 2.5V for green, and 3.0V for blue emitters.

The fundamental engineering trade-off involves balancing color accuracy, power efficiency, and manufacturing yield while maintaining precise control over each subpixel's spectral output across varying brightness levels.

This page brings together solutions from recent research—including current-balanced driving architectures, stacked subpixel configurations, wavelength-compensation techniques, and adaptive pulse-width modulation schemes. These and other approaches focus on achieving consistent color reproduction while addressing manufacturing scalability and power management requirements.

1. Micro LED Display with Stacked Sub-Pixel Structure and Integrated Reflective Top LEDs

Seoul Viosys Co., Ltd., 2023

Micro LED display with stacked sub-pixels to reduce interference and improve brightness. The display uses stacked sub-pixels, each containing multiple LEDs, instead of individual LEDs for sub-pixels. This allows higher pixel density with fewer LEDs per substrate. The stacked sub-pixels are arranged in a pixel with the bottom LED emitting through the top LEDs. The top LEDs reflect back emitted light from bottom LEDs to avoid color mixing. This eliminates the need for color filters. The stacked sub-pixels are electrically connected with vias. The stacked sub-pixel structure reduces interference compared to side-by-side LEDs.

2. Display Device with Subpixel LED Driving Current Pulse Amplitude and Width Control

Lextar Electronics Corporation, 2022

Display device with adjustable color performance by selectively controlling the driving current pulse amplitude and width for each subpixel's LED. This allows compensating for variation in LED peak wavelengths and improving color fidelity and reducing color deviation. The subpixels each have a LED and control circuit. The circuits provide different driving current pulse amplitudes to make the LEDs emit at the target wavelength. They also provide varying pulse widths to adjust LED brightness.

US20220398973A1-patent-drawing

3. Micro LED Display with Independently Driven Dual-Color Subpixels and Grayscale-Dependent Current Ratio Adjustment

PlayNitride Inc., 2022

Micro LED display with improved color accuracy at high brightness levels. The display has subpixels with two micro LEDs of different colors driven independently. The current ratio between the micro LEDs is adjusted based on grayscale level. This prevents color shift as driving current increases. At low grayscale, only the shorter wavelength micro LED is on. At high grayscale, only the longer wavelength micro LED is on. In between, the longer wavelength micro LED current increases relative to the shorter wavelength micro LED. This maintains consistent color appearance at all grayscales by matching dominant wavelengths.

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4. Micro LED Color Display Device with Independent Subpixel Optimization Structure

Shenzhen China Star Optoelectronics Technology Co. Ltd, 2018

Micro LED color display device with improved color uniformity and stability. The display has blue, green, and red subpixels sandwiched between a driving substrate and a package substrate, with a support in between. This sandwich structure allows independent optimization of each color subpixel without affecting the others. This improves color uniformity by reducing deviations from LED binning and allows easier control of green color stability compared to traditional RGB displays.

5. MicroLED Display with Multi-Sub-LED Pixel Structure and Light Crosstalk Barrier

LEIYU OPTOELECTRONICS TECH SUZHOU CO LTD, LEIYU OPTOELECTRONICS TECHNOLOGY CO LTD, 2024

MicroLED display with individually controllable pixel brightness. The display uses a unique pixel structure with multiple sub-LEDs surrounded by a barrier. Some sub-LEDs emit the main color while others emit a secondary color. Driving individual sub-LEDs allows controlling the overall pixel brightness by selectively turning on sub-LEDs. This avoids the issue of brightness regulation in conventional MicroLEDs where all subpixels are driven together. The barrier prevents light crosstalk between adjacent pixels.

6. Micro-LED Display Module with White Light Emission and Integrated Color Conversion Filters

NANCHANG SILICON BASED SEMICONDUCTOR TECH CO LTD, NANCHANG SILICON-BASED SEMICONDUCTOR TECHNOLOGY CO LTD, NANCHANG UNIV, 2023

Micro-LED full-color display module and preparation method that improves color purity and stability compared to traditional microLED displays. The method involves generating white light microLED arrays on a drive substrate through spontaneous emission. Then, color conversion filters are added to each group of microLEDs to separate the white light into red, green, and blue pixels. This allows periodic arrangement of red, green, and blue subpixels in each cycle to create full-color pixels. It eliminates the need for precise microLED transfer and color conversion media like phosphors or quantum dots.

7. Micro LED Display Panel with Unequal RGB LED Distribution for Uniform Current Drive

GM GLOBAL TECH OPERATIONS LLC, GM GLOBAL TECHNOLOGY OPERATIONS LLC, 2023

Micro LED display panels with improved color accuracy and robustness by having each pixel contain different numbers of red, green, and blue LEDs to drive them with the same current level. This allows the pixel to emit a predetermined color when all LEDs receive the same current. This simplifies LED driving and improves color consistency compared to using different currents for each LED color.

8. Circuit for Real-Time Chromaticity Calculation and Adjustment in Mixed LED Light Systems

SHENZHEN XIAOYANG ENG CONSULTING CO LTD, SHENZHEN XIAOYANG ENGINEERING CONSULTING CO LTD, 2022

Circuit for real-time adjustment and control of mixed LED light colors. The circuit uses a main control module to analyze and calculate mixed light information to obtain accurate chromaticity coordinates. This data is then used by the LED driver module to calculate precise chromaticity values for the LEDs to mix the light with more accurate colors. Additionally, the main control module can adjust the mixed light information in real-time for scene-specific color conversion needs. This allows more precise and dynamic mixed LED light color capabilities compared to fixed color LED arrays.

9. Display Device with Multiple LED Groups and Adjustable Current Drivers for Color Uniformity

SHENZHEN TCL NEW TECH CO LTD, SHENZHEN TCL NEW TECHNOLOGY CO LTD, 2021

Display device with improved color uniformity using multiple LED groups and adjustable driving currents. The display has multiple LED groups, each with LEDs in the same BIN range. Dedicated drivers connect 1:1 to each group. By adjusting the drivers' output currents, the LED groups' emission wavelengths can be matched to reduce color variation. This allows using LEDs from different BIN ranges in a display instead of all matching. It improves cost vs uniformity tradeoff compared to using same-BIN LEDs in each group.

10. Integrated Color MicroLED Display with Patterned Blue LED Layer and Color Conversion

FACEBOOK TECHNOLOGIES LLC, 2021

Low-power, high-brightness integrated color microLED display. The display is fabricated by a method involving growing a blue LED epitaxial layer on a sapphire substrate, patterning openings in the blue LED layer to expose the underlying substrate, forming ohmic contacts on the exposed substrate, and transferring the blue LED array onto a receiving substrate with drivers. A color conversion layer is added to change the blue light to other colors. This provides a compact, self-contained microLED display with integrated color conversion.

11. Micro LED Display with Individually Controllable Subpixels for Independent Emission Time and Duty Cycle Adjustment

VueReal Inc., 2020

Micro LED display system and method for improving dynamic range, power consumption, and color accuracy. The display has individually controllable subpixels in each pixel. This allows independent adjustment of emission time and duty cycle for each subpixel. This enables optimizing power consumption and color accuracy without affecting gamma. By dynamically adjusting subpixel emission times, it tunes display color without affecting gamma.

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12. Five-Primary Color LED Display with Independent Dimming Control for Expanded Color Reproduction

SHENZHEN DART ILLUMINATION CO LTD, 2020

Five-primary color LED display device with improved color gamut compared to traditional three-primary color displays. The display uses red, yellow, green, cyan, and blue LEDs. A control circuit with dimming allows independent adjustment of each primary color. This expands the display's color reproduction capabilities to better match real-world colors and meet high-end requirements for wide color gamut. The separate control of each primary color allows more accurate reproduction of a wider range of colors compared to just varying the intensity of the three primaries.

CN112017586A-patent-drawing

13. Active Display with Individually Controllable RGB LED Subpixels for Expanded Color Gamut

IMAX Theatres International Limited, 2020

Active display with increased color gamut using individually controllable RGB LED subpixels to overcome limitations of fixed color bins. The display has a pixel made of multiple RGB LED subpixels. Each subpixel has individually adjustable red, green, and blue LEDs. By varying the intensity of each LED, the pixel can output light in a wider color gamut than any individual subpixel LED could achieve on its own. This allows using more LEDs from a production batch to cover a desired display color space like DCI-P3 or Rec. 2020.

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14. Monolithic LED Display Panel with Common Multi-Quantum Well Structure and Adjustable Subpixel Emission

The Hong Kong University of Science and Technology, 2020

Monolithic full-color LED display panel with improved color gamut and simplified fabrication compared to prior art. The panel has pixels with red, green, and red subpixels, where each subpixel uses a common multi-quantum well structure. The subpixel compositions are adjusted at different current densities to emit primary colors. A conversion layer changes the third subpixel's color. This allows full-color without color conversion layers or complex assembly. The common structure simplifies fabrication versus individual RGB LEDs.

15. Color PLED Display with Stacked Micro LED Layers and Alternating Voltage Color Selection

FUZHOU UNIVERSITY, UNIV FUZHOU, 2019

Color PLED display with individual color pixels to eliminate the need for separate red, green, and blue subpixels or color conversion. The display has micro LEDs with stacked layers emitting different colors. A blocking layer separates the color layers. By applying alternating voltage to drive the pixels, carriers are selectively compounded in each layer to emit the desired color. This avoids transferring and aligning multiple subpixels and simplifies manufacturing compared to traditional RGB displays.

16. LED Pixel Device with Defined Chromaticity Ranges for Enhanced Color Matching

上海三思电子工程有限公司, 上海三思科技发展有限公司, 三思光电科技有限公司, 2019

LED pixel device, display screen, and method that improves color accuracy and matches LED displays to video signals without losing color gamut. The LED pixel device has red, green, and blue LEDs with specific chromaticity ranges. The red falls between (0.682, 0.301) to (0.700, 0.299), green between (0.21, 0.65) to (0.28, 0.65), and blue between (0.136, 0.040) to (0.146, 0.056). This matching reduces color difference compared to standard LEDs. The display mixes the LED lights at predetermined ratios to create primary colors from the matched LEDs instead of trying to convert video primaries to LED primaries.

17. LED Pixel Lamp with Central White and Peripheral RGB LEDs Under Integrated Lens for Uniform Color Transition

深圳爱克莱特科技股份有限公司, 2019

A color-changing full-color LED pixel lamp with uniform color transition and improved durability. The lamp has a substrate with white light LEDs in the center and RGB LEDs on either side. An integrated lens covers all the LEDs. A microcontroller on the substrate controls the color temperature by adjusting the RGBW values. The integrated lens provides secondary light distribution for uniform color mixing. The lamp has a containing cavity with a lens window for exposed light. The substrate clips into the cavity and sealing glue fills gaps. The integrated lens and substrate are fixed to the cavity walls for protection.

CN208951978U-patent-drawing

18. Micro LED Display with Independent Subpixel Brightness and Duty Cycle Control

VUEREAL INC, 2019

Micro LED display optimization technique to improve dynamic range, power consumption, and color accuracy. The technique involves independently controlling the brightness and duty cycle of each subpixel in a micro LED display. This is done by providing separate light-emitting control signals to each subpixel of each pixel in the array. The signals can independently control the light-emitting time and duty ratio of each subpixel. This allows more precise and optimized brightness control compared to driving the whole pixel. It also enables better color accuracy and gamma correction. By separately controlling each subpixel, it allows mixing of primary colors with different duty cycles to achieve desired white points. This mitigates the efficiency drop at lower currents seen in some micro LEDs.

CN109493744A-patent-drawing

19. MicroLED Display with Subpixel Wavelength Conversion Layer for Consistent Color Across Brightness Modes

AU OPTRONICS CORP, 2018

MicroLED display with reduced color shift between low and high brightness modes. The display uses subpixels with a wavelength conversion layer covering a lower current microLED and not covering a higher current microLED. In low brightness mode, the conversion layer emits light with colors close to the higher current microLED in high brightness mode, reducing color shift between modes.

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20. Micro LED Display with Sequential Subpixel Arrangement and Independent Electrode Addressing Modules

广东迅扬科技股份有限公司, 清华大学深圳研究生院, 2018

Micro LED color display structure with separate electrode addressing modules for each subpixel to precisely control color emission. The red, green, and blue subpixels are arranged in sequence on a transparent substrate. This eliminates the need for complicated transfer of discrete colored microLEDs, simplifying manufacturing and reducing defects compared to transferring pre-made microLEDs of different colors. The separate electrode modules allow independent driving of each subpixel using a driving circuit board.

CN108172591A-patent-drawing

21. LED Light Source with Separate White, Red, Green, and Blue Units for Precise Color Parameter Adjustment

22. LED Light Source with Individually Adjustable RGBW Units for Precise Color Parameter Control

23. Mixed Light Generating Device with Independently Controlled RGB LEDs and Network-Connected Microprocessor

24. Display System with Sub-Pixels Incorporating Heterogeneous Light Emitters with Distinct Attributes

25. Multi-Group LED Emitter on Ceramic Substrate with Independently Adjustable Broad-Spectrum Phosphor-Coated and Narrow-Band LED Arrays

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