Screen Door Effect Elimination in Micro-LED Displays
Micro-LED displays face distinct visual challenges at viewing distances under 30cm, where the physical gaps between pixels become perceptible as a screen door effect. Current designs achieve pixel densities of 200-300 PPI, but even at these resolutions, the inactive areas between emitters can create visible mesh patterns that degrade image quality and viewer immersion.
The fundamental challenge lies in maximizing the active emission area while maintaining the electrical isolation and thermal management requirements of densely packed micro-LED arrays.
This page brings together solutions from recent research—including curved light diffusion layers, anisotropic optical stacks, optimized sub-pixel LED distributions, and multi-layer diffusion techniques. These and other approaches focus on practical methods to improve perceived image continuity without compromising display brightness or reliability.
1. Micro LED Display Panel with Uniformly Distributed Sub-Pixel Micro LED Array
SHENZHEN CHINA STAR OPTOELECTRONICS TECHNOLOGY CO., LTD., 2018
Micro LED display panel with improved resolution, reduced screen door effect, and lower cost compared to conventional micro LED displays. The panel has an array of sub-pixel areas on the substrate, each filled with uniformly distributed micro LEDs. This allows higher resolution by packing more LEDs in each sub-pixel without increasing inter-pixel gaps. By optimizing the number of LEDs per sub-pixel, it balances resolution, screen door effect, and cost compared to using a single large LED per sub-pixel. The micro LEDs are transferred using a process like micro transfer printing.
2. Emissive Display Pixel Arrangement with Diffusers and Polarized Lenses for Enhanced Image Uniformity and Reduced Pixelation
IMAX CORP, 2025
Light conditioning and angular management techniques for emissive displays like LED walls to improve image quality and reduce pixilation in applications like cinema. The techniques involve modifying the light emission characteristics of the display pixels to mimic the randomness and uniformity of film projection. This is done by adding diffusers in front of the pixels, randomizing the pixel brightness centers, and using lenses with polarizers to fill the gaps between pixels. The goal is to reduce the visible pixel structure and screen door effect in close viewing distances like cinema. The techniques also enable stereoscopic 3D displays using polarization, spectral separation, or time multiplexing.
3. Display Panel with Microprism Light Concentration for Enhanced Resolution and Aperture Ratio
TCL CHINA STAR OPTOELECTRONICS TECHNOLOGY CO LTD, 2025
Display panel and device with improved resolution and aperture ratio by using microprisms to concentrate light from individual LED pixels. The display panel has LED chips, driving circuitry, and an encapsulation layer. Microprisms are arranged above the LEDs, with one prism corresponding to each LED. The prisms have protrusions that focus the LED light. This reduces the angle of emitted light, minimizing mixing with neighboring pixels and eliminating the need for black matrix. It also brings the prism closer to the LED for better focusing. The prisms can be disposed on the encapsulation layer or directly above the LEDs. This reduces color shift, improves aperture ratio, and decreases pixel pitch compared to conventional displays with black matrix.
4. Micro LED Array with Stacked Semiconductor Layers, Metal Pads, Reflective Coatings, and Integrated Optical Structures
LEXTAR ELECTRONICS CORP, 2025
Micro LED structure and display device with optical structures for improved light patterns in applications like augmented reality and virtual reality. The micro LED structure has multiple micro LED chips, each with a stacked semiconductor layer, metal pad, and reflective coating. Optical structures are placed over each micro LED chip. A planarization layer surrounds the micro LEDs. The optical structures enhance the light extraction efficiency from the micro LEDs for better AR/VR performance.
5. Display Device with Micro LED Sub-Pixels Incorporating Planarization and Optical Layers for Enhanced Light Containment
LG DISPLAY CO LTD, 2025
Display device using micro LEDs with improved light efficiency and display performance. The display has sub-pixels with emitting areas and non-emitting areas. Each sub-pixel has multiple micro LEDs covered by a planarization layer with openings. Optical layers fill the openings to cover the micro LEDs. This design allows light emission from the micro LEDs to be trapped and guided by the optical layers instead of escaping through the sides. The planarization layer and optical layers prevent light leakage through the gaps between the micro LEDs.
6. Display Device with Micro-LEDs Surrounded by Non-Overlapping Scattering Layer
LG DISPLAY CO LTD, 2025
Display device using micro-LEDs with improved brightness uniformity and reduced power consumption by surrounding the micro-LEDs with a scattering layer. The scattering layer surrounds the bonding layers connecting the micro-LEDs to the substrate. This prevents the micro-LEDs and scattering layer from overlapping when transferring the micro-LEDs, which can cause misalignment and uniformity issues. By surrounding the bonding layers with scattering, it extracts more light from the micro-LEDs and provides consistent brightness from all viewing angles.
7. Sidewall Suppression and Top Surface Enhancement of Light Extraction Efficiency in Vertically Stacked Full‐Color Micro‐LEDs Based on L‐Shaped Metal Walls
h x guo, jun he, jie sun - Wiley, 2025
Abstract Micro lightemitting diodes (MicroLEDs) are regarded as the core of nextgeneration display technology due to their high brightness and energy efficiency. However, reduction in size MicroLEDs has led increased manufacturing challenges exacerbated issues such sidewall emission, which hinder development highpixeldensity displays. This paper proposes a vertically stacked MicroLED design based on an Lshaped metal wall structure, aiming suppress emission enhance top light extraction efficiency (LEE). Through parameter scanning, dimensions thickness epitaxial layer optimized. Combined with inclined sidewalls reflective structure wall, optical characteristics red, green, blue analyzed using raytracing simulations. The is significantly reduced (with maximum 68.04% compared without walls), enhanced (the LEE within 90 direction for blue, red by 196.18%, 51.69%, 3.45%, respectively, walls). simulation results demonstrate potential fullcolor displays, providing new approach suppressing crosstalk improving performance.
8. Display Device with Central Optical Module and Light Blocking Layer for Distortion Mitigation
SAMSUNG DISPLAY CO LTD, 2025
Display device with an optical module that provides an improved image by mitigating distortion and artifacts. The display has a lower substrate with areas around an optical module area. The optical module is in the center area. An upper substrate covers the light emitting area. A filling layer between the upper and lower substrates fills the center area. A light blocking layer surrounds the center area on the upper substrate. This configuration reduces external light introduction into the optical module while preventing wavefront distortion.
9. Light Emitting Element Arrangement with Shared Lens for Uniform Appearance
MAKITA CORP, 2025
Arranging multiple light emitting elements for a display device or work machine in a way that reduces differences in appearance when viewed through a shared lens. The display device has a support structure inside the housing that holds two or more light emitting elements emitting light in the same direction. A shared lens propagates the light from the emitting elements to the outside. This allows communization of the lens between the emitting elements, reducing efficiency losses from individual lenses. But by arranging the emitting elements with similar characteristics, it minimizes differences in the displayed lighting appearance viewed through the shared lens.
10. Display Substrate with Pixel Circuits Incorporating Sequential Light Emission and Shared Current Control for Enhanced Resolution
BOE TECHNOLOGY GROUP CO LTD, 2025
Display substrate for near-eye displays like AR/VR headsets with improved resolution and reduced screen door effect. The display has a matrix of pixel circuits with multiple connected light emitting devices per circuit. Each pixel circuit has a current control sub-circuit and a light emitting selection sub-circuit. The current control sub-circuit provides drive current to a shared node. The light emitting selection sub-circuit sequentially connects the node to multiple light emitting devices of the same color. This allows higher resolution by connecting multiple light emitting devices per circuit instead of one per pixel. The selection sub-circuit prevents simultaneous light emission. The display also has features like stacked transistors, overlapping connections, and separated color emitting devices to further optimize resolution and performance.
11. Display Device with Stacked Structure and Graded Refractive Index Insulating Layers
SAMSUNG DISPLAY CO LTD, 2025
Display device with improved light extraction efficiency and display quality by reducing internal reflections. The display has a stacked structure with a substrate, transistor, light emitting element, encapsulation layer, sensing electrode, and insulating layers. The insulating layers have progressively increasing refractive indices from the bottom to the top. This graded index structure helps light rays escape the device by reducing total internal reflections at the interfaces between layers.
12. Origin of reduced efficiency in GaN-based micro-LEDs studied by scanning near-field optical microscopy
rinat yapparov, matthew s wong, tanay tak - American Institute of Physics, 2025
The quantum efficiency of micro-light emitting diodes (micro-LEDs) is lower than that large area LEDs. This reduction typically attributed to the nonradiative ShockleyReadHall recombination at surface defects and current leakage through sidewall region without a clear distinction between these effects. In this work, we attempt find out which phenomena most critical for reduced micro-LEDs. has been done by mapping electroluminescence (EL) photoluminescence (PL) measuring PL dynamics in blue GaN micro-LEDs fabricated dry etching. It found as-etched device, EL intensity much devices with KOH etching atomic layer deposition SiO2. effect especially pronounced close sidewalls. On other hand, decay times are similar passivated devices, both their center allows concluding main mechanism not recombination. be efficient means eliminate leakage.
13. Monolithic Micro LED Display Element with Flip-Chip Mount and Absorbing Structure
TOYODA GOSEI CO LTD, 2025
Flip-chip mounted monolithic micro LED display element with improved contrast. The element has a substrate, n-type, light-emitting, and p-type layers. Each light-emitting part has a first electrode on the p-type layer. An absorbing structure is above the first electrode with alternating dielectric and metal layers. A through hole connects the absorbing structure to a second electrode above. This prevents light transmission between pixels and reduces reflection/contrast loss.
14. Display Substrate with Light Dimming and Fixing Layers for MicroLED Arrays
BOE TECHNOLOGY GROUP CO LTD, BOE MLED TECHNOLOGY CO LTD, 2025
A display substrate design with improved contrast, light mixing reduction, and device fixation for microLED displays. The display substrate has a first light dimming layer between groups of microLEDs that absorbs external light and emitted light to improve contrast and prevent light mixing. A first fixing layer on the microLED side absorbs light and fixes the microLEDs to prevent falling. The light dimming and fixing layers are formed using inkjet printing.
15. Color Conversion Substrate with Overlapping Layer Light Blocking Structure
SAMSUNG DISPLAY CO LTD, 2025
Color conversion substrate for displays that prevents or reduces side light leakage. The substrate has a base with display area and peripheral area. A color filter is in the display area. A front light blocking member with overlapping colored layers is in the peripheral area. A side light blocking member outside the front member surrounds it. The side blocking member has overlapping colored layers. This effectively traps light from the front blocking member to prevent side light leakage.
16. Display Device with Grooved Substrate for Reduced Light Reflection in Transmission Areas
SAMSUNG DISPLAY CO LTD, 2025
Display device with reduced light reflection from transmission areas to improve image quality. The display has a substrate with grooves corresponding to the transmission areas. This reduces diffraction and reflection of light passing through the transmission areas compared to a plain substrate. The grooves can have varying widths to constructively interfere with light passing through protrusions on the substrate. This constructive interference reduces light loss as it travels from the display elements to the substrate and back.
17. Display Device with Stacked Insulation Layers Featuring Selective Openings and Refractive Index Variation
SAMSUNG DISPLAY CO LTD, 2025
Display device with improved light extraction efficiency and display quality by optimizing the internal structure around the pixels. The display has multiple color subpixels (RGB) on a substrate. Insulation layers are stacked above the subpixels. The lower insulation layer has openings overlapping some subpixels. A higher refractive index upper insulation layer is filled in these openings. This prevents light reflection at the interface between the two insulation layers. The openings are placed strategically to avoid overlapping some subpixels. This prevents light trapping when exiting the display. By selectively modifying the insulation layer stack around some subpixels, overall light extraction is increased while preserving color accuracy.
18. MicroLED Structure with Extended Active Layer Beyond Electrode Edges for Enhanced Light Extraction and Uniformity
JADE BIRD DISPLAY LTD, 2025
MicroLED structure and chip design that enables efficient manufacturing of microLED displays with reduced yield loss and improved uniformity. The microLED design involves extending the active light emitting layer beyond the edges of the top and bottom electrodes. This prevents the active layer from being completely covered by the electrodes, allowing the emitted light to spread out horizontally. The electrode edges align vertically to maintain contact, but the active layer extends laterally. This prevents light confinement and improves extraction efficiency. Sharing the active layer between multiple microLEDs also reduces variations in material quality and thickness. Isolation structures between microLEDs can be formed in the shared active layer to prevent light crosstalk.
19. Display Panel Cutting Method with Offset Substrate Lines for Reduced Edge Light Leakage
FUZHOU BOE OPTOELECTRONICS TECHNOLOGY CO LTD, BOE TECHNOLOGY GROUP CO LTD, 2025
Cutting a display panel to reduce light leakage at the edges and eliminate white borders or bright borders. The cutting method involves cutting the color-film substrate along a first line and the array substrate along a second line, with the second line moved inward by a preset distance relative to the first line. This reduces the exposed area of the array substrate edge if there are cutting errors, preventing light leakage from metal parts.
20. Display Panel with Block-Patterned Light-Transmitting Regions and Varying Structural Attributes
SHANGHAI TIANMA MICRO-ELECTRONICS CO LTD, 2025
A display panel and display device with reduced diffraction in transparent regions to improve display quality. The display panel has light-transmitting regions arranged in a block pattern with adjacent regions of different types. This prevents clustering of identical regions that can cause diffraction. The block layout with varying regions reduces diffraction artifacts when viewing objects through the transparent panel. The panel can have multiple blocks with varying arrangements in rows and columns. The blocks can also have different thicknesses, materials, or sub-film layers.
Get Full Report
Access our comprehensive collection of 23 documents related to this technology