Improved Light Extraction from Micro-LEDs

Display panels with high-efficiency micro-LED structures for high resolution, high brightness displays. The micro-LED design has a conductive side arm that contacts the bottom layer of the LED stack to improve the p-type ohmic contact and avoid shadowing of emitted light. The LED also has a composite reflective layer under the bottom contact to maximize light extraction. The micro-LED structure includes a bottom conductive layer, a light emitting layer, top contact, a dielectric layer, and the conductive side arm connecting the bottom layer. The composite reflective layer includes insulating and metallic layers.

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An optical device with improved light extraction efficiency and manufacturing method. The method involves forming spacers on the sidewalls of a sacrificial mesa, depositing a reflective metallic layer on the spacers, removing the mesa to create a pocket between the spacers, and installing a die with vertical sidewalls into the pocket. The spacers and reflective layer help direct and reflect light generated in the die toward the top surface for extraction. This improves extraction compared to conventional LEDs, where light can be trapped and absorbed in the sidewalls. The spacers and reflective layer provide an optical cavity around the die to enhance light's internal reflection and extraction.

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Micro-LED arrays are formed using vertical sidewall spacers to enhance light extraction. The devices have a light-emitting structure with vertical sidewalls, an optically transparent spacer layer with an internal face facing the sidewalls to enhance light extraction and a reflective conducting mirror layer on the external face of the spacer.

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Micro-LED display panel with improved efficiency and fabrication method. The micro-LED structure has a unique design to enhance light extraction efficiency. It includes a conductive side arm that connects the bottom layer of the LED to the bottom contact layer. This creates a vertical current path that avoids current crowding and improves uniform current spreading. The LED also has a composite reflective layer underneath the bottom contact to increase reflectivity. This helps trap and redirect oblique angle light for extraction. The micro-LED structure uses a transparent isolation layer to cover the sidewalls and protrude the top of the LED layers, allowing a top contact to be added over the transparent layer.

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Double color micro LED display panel for increasing light output rate and resolution. The panel has pixels with a first light emitting layer and a second light emitting layer that emit different colored light. Barrier components between pixels block light transmission between pixels. The second light emitting layers are bonded using non-metallic material to prevent electrical shorting.

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A method to optimize light extraction efficiency of small micro-LEDs and improve their brightness. The method involves forming spacers on the sidewalls of the LED mesa using an insulating material. A transparent conducting oxide layer is then deposited on the top surface of the mesa, followed by a reflective conducting layer. The spacers and transparent oxide layer act as an optical cavity to enhance light extraction. The insulating spacers prevent electrical leakage between the transparent and reflective layers. This prevents damage to the active region while maximizing light extraction.

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Micro-LED design with high extraction efficiency for displays. The LED has a conductive bottom layer, a light-emitting layer, and a top conductive layer. It includes a protruding section on the bottom layer that extends beyond the other layers. A transparent isolation layer covers this protrusion. A side arm connects the bottom layer to the bottom conductive layer. The bottom conductive layer also has a composite reflective layer underneath.

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Micro-LED display panels with high-efficiency pixels for high resolution, high brightness displays like AR and VR devices. The micro-LED pixels have a unique structure with improved light extraction efficiency, high reflectivity, and good ohmic contacts. The key features are a conductive side arm that contacts the bottom layer of the LED stack, a composite metal-dielectric reflective layer beneath the LED stack, and a protruding top layer covered by a transparent isolation layer. This design reduces light trapping, improves reflectivity, and allows better electrical contacts.

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A micro-LED structure for AR/VR displays with improved light patterns uses optical structures like lenses and reflective cups over each micro-LED chip. The micro-LED structure includes multiple micro-LED chips arranged in a line, each with a reflective coating around the sidewalls. Optical structures, such as asymmetric lenses and reflective cups, are placed over each micro-LED chip to shape and direct the light output.

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An LED assembly to improve micro-LEDs' light efficiency, brightness, and integration. The assembly involves vertically aligning micro-LEDs into the substrate through holes rather than laying flat. This optimized alignment significantly improves light efficiency, brightness, and integration of the micro-LEDs compared to horizontal alignment.

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Display panels with integrated micro-lens arrays and pixel structures for high resolution, high brightness displays with reduced power consumption. The display panels include micro-lenses aligned to pixel light sources to reduce light divergence and improve extraction efficiency. The pixel structures have multi-color LEDs stacked vertically with reflective layers to prevent crosstalk. The stacked LEDs are bonded with dielectric layers and connected to a common electrode. The vertical arrangement allows high resolution within each pixel while the micro-lenses increase overall brightness. The reduced divergence and improved extraction efficiency provide high brightness for better viewing angles and reduced power waste.

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Micro-LED display technology with high light extraction efficiency for improved efficiency and reduced power consumption compared to OLED displays. High-efficiency micro-LED displays are particularly useful in mobile devices with critical battery life. The micro-LEDs are made from nanowires with textured semiconductor materials to scatter and extract more light.

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Display devices using micro-LEDs with improved light extraction efficiency and a manufacturing method for the same. The micro-LEDs have protrusions on their surface, roughness, and nanoparticles that scatter light, allowing more efficient extraction. The protrusions are formed by coating the LED with an organic layer containing nanoparticles and etching the layer to leave behind the protrusions and roughness. This simple and inexpensive organic layer process enhances light extraction compared to conventional dry or wet etching methods.

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Micro LED structure that improves efficiency and brightness of micro-LED devices. The micro-LED structure has a light emitting layer that extends horizontally beyond the top and bottom electrodes, unlike conventional designs where the light emitting layer is sandwiched strictly between the electrodes. This allows more light extraction and reduces absorption losses. The micro-LED structure can also include shared spacers and isolation structures between multiple micro-LEDs on a chip to further enhance efficiency.

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Micro-LED structure with enhanced brightness. The micro-LED structure includes a first conductive layer, a second conductive layer, and a light emitting layer between them. The light emitting layer extends horizontally away from the edges of the conductive layers without contacting them. This allows the light emitting layer to extend further and emit more light compared to conventional micro-LED designs where the light emitting layer is sandwiched between the conductive layers.

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MicroLED structure with improved light extraction efficiency for use in displays, using shared light emitting layer. The structure includes microLEDs with a top and bottom contact layer and a continuous light emitting layer in between. The LEDs share the same emission layer. This allows the layer to be optimized for light extraction efficiency. The shared layer extends horizontally beyond the contact layers to avoid contact and improve extraction.

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Micro-sized face-up LED device for visible light communication applications. The device has a high efficiency micro-hole array structure that allows more light extraction. The LED is prepared from a GaN-based epitaxial layer with a central current spreading layer and etched N-GaN layer surrounded by passivation.

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Micro light emitting diode (LED) that boosts light extraction and efficiency, and a manufacturing method of the micro LED. The micro LED has a vertical side surface for better light extraction and a tilted side surface to increase LED density. By surrounding the sides with insulating and reflective layers, light emitted from the tilted side is reflected and extracted from the vertical side. This improves light extraction efficiency. The manufacturing method involves etching the vertical side after the tilted side is formed.

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Micro-LED display technology that enables mass production of high efficiency, high brightness micro-LED displays. The display uses nanorod-type micro-LEDs with a functional material layer that increases light extraction. The functional layer has gradually decreasing refractive index away from the LED surface to reduce total internal reflection. The display further uses pixel plates containing multiple subpixels with differently composed nanorod LEDs to emit different colors.

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Micro-LED arrays and micro-lens arrays to improve the efficiency of micro-LED-based displays. The micro-LEDs have optimized mesa shape and back reflectors to increase extraction efficiency. The micro-LEDs are combined with micro-lenses that extract and direct the light for improved coupling into display systems and user eyes.

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