Optical Modules for Micro-LED Displays

Micro-LED display pixels to improve color purity and efficiency by collimating emitted light and reducing cross-talk between sub-pixels. Each pixel has multiple sub-pixels with lenses and reflectors that contain and redirect the emitted light. The reflectors reflect pump light and transmit converted light. They also have apertures to limit cross-talk. This improves efficiency by preventing unconverted pump light from escaping the pixel. The lenses collimate the light to increase collection efficiency. The reflectors and lenses are designed to match and optimize the sub-pixel emissions.

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MicroLED pixel configuration and display panel design to avoid dispersion and color inconsistency problems in small angle microLED displays. Multiple microLEDs of different colors are arranged on a circular arc with a common center point. The microLEDs emit light towards an optical component that collects and emits the light at a preset angle. The microLEDs are positioned so their light beams coincide after rotating around the center point. This ensures the emitted light from all microLEDs enters and exits the optical component at the same angle, preventing dispersion and color variation when using optical components to narrow the viewing angle.

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Micro-LED display module with built-in color conversion function to improve efficiency and simplify manufacturing of micro-LED displays without separate color conversion layers. The display has a micro-lens array above the micro-LEDs. The lenses focus and direct the light while the array's barriers and color converters between the lenses convert the LED colors. This eliminates the need for separate color conversion films. The converters are formed in the barriers using quantum dot ink. The array also has absorber layers to prevent cross-talk and reflection layers to increase efficiency.

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Micro LED structure for AR/VR displays with improved light patterns using 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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Backlight unit for displays that uses mini-LEDs or micro-LEDs as light sources for improved contrast and power efficiency. The backlight has a color conversion sheet to convert the LED light, a first diffusion lens sheet with triangular pyramid lenses aligned in one direction, and a second diffusion lens sheet with triangular pyramid lenses aligned in another direction at an angle to the first. This separates and diffuses the LED light to reduce hot spots and improve uniformity.

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LED display panel with integrated micro lenses for improving brightness and reducing crosstalk in LED displays. The panel has an array of pixel driver circuits, an array of LED dies, an array of micro lenses, and an optical spacer between the LED and micro lens arrays. The micro lenses are formed on the LEDs to collimate the light emission and reduce divergence. This improves display brightness, reduces light crosstalk between pixels, and allows using projection lenses with smaller apertures.

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Micro-LEDs with micro-lenses for improving efficiency of micro-LED displays and eye tracking. Micro-LEDs with mesa structures and backside reflectors are paired with micro-lenses. The lenses extract light from the LEDs and direct it in desired directions. This optimizes the beam profiles for efficient coupling into waveguide displays and onto users' eyes. The lenses have offsets from the LED centers that vary across the array. This causes the lens chief rays to propagate at angles that counteract walk-off in the display optics. The LEDs themselves have narrow beam profiles for high extraction efficiency.

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Micro light emitting diodes (μLEDs) used as a light source for displays and other applications suffer from poor collimation of the emitted light due to their small size. Waveguides made of transparent crystalline semiconductor material are used as secondary optics to reduce the beam divergence of μLEDs. The waveguides capture and confine the light from the LED to transmit it with reduced divergence. This allows efficient collimation without using lenses. The waveguides are fabricated from crystalline semiconductor materials like GaN that are transparent to the LED's emission wavelengths.

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Optical film for diffusing and collecting light from mini or micro LEDs that efficiently and uniformly diffuses and collects the light from mini LEDs or micro LEDs. The film includes a first diffusing sheet with a bead diffusion layer on one surface and a pattern diffusion layer on the other surface, and a prism sheet to collect the diffused light. The bead layer difuses light more than the pattern layer to optimize diffusion from mini LEDs.

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Semiconductor light emitting devices like LEDs with planar optical components to more precisely modify the emission pattern using epitaxial growth and lateral oxidation/etching techniques. The components are formed from multiple semiconductor layers with varying compositions that oxidize/etch at different rates. Trenches are formed and the layers oxidized/etched to create optical components like micro-lenses or prisms. The layer thickness and composition are precisely controlled to fabricate the components using standard semiconductor processing. This allows integrated and efficient fabrication of devices with tailored light emission.

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Techniques for extracting light from a micro-LED array using a micro-lens array to improve efficiency over conventional methods. The micro-lens array is formed with a pitch different from the LED array pitch. This allows each micro-lens to collimate, focus, and direct light from its corresponding LED across the array in different directions. The offsetting focuses the collimated rays of each LED. The micro-lens array can be formed by reflowing patterned polymers like photoresist.

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A high light-extraction efficiency light-emitting diode (LED) design that uses asymmetric protruding microstructures on the LED surface to increase light extraction. The protruding microstructures improve light extraction by reducing internal reflection and increasing the escape cone angle. The microstructures can be on the substrate surface, the LED layer surface, or both. They are asymmetric and angled to scatter and redirect light outwards. This boosts the LED's overall brightness and efficiency.

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Improving the efficiency of light-emitting diode (LED) devices. The LEDs are integrated with lenses and mirrors that shape and direct the emitted light. The optics improve efficiency by reducing light trapping and reflection within the LED package. The integrated LED/optics arrays are manufactured using techniques like dispensing and curing encapsulation material over multiple LEDs simultaneously and mounting pre-fabricated LED die onto a packaging substrate before laminating molded micro-mirror reflectors around them.

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Self-aligning optical structures over printed, pre-formed light emitting diodes (LEDs). It involves printing a very thin layer of omniphobic liquid over the LEDs. The liquid wicks off the bumps of the underlying LED tops and only resides in the low areas of the conductive layer between the bumps. The cured liquid layer then exposes the bumps through the omniphobic layer above each of the LEDs. The exposed portion is about the same size as the underlying LED. This provides a self-aligned opening for subsequent printing steps to accurately place optical structures over individual LEDs in the random array.

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A high angular resolution light field display using micro-LED devices with directional collimating parabolic mirrors. The display has arrays of micro-LEDs where each micro-LED has a parabolic mirror that collimates the light output into a narrow angular range. This provides each pixel with angular resolution instead of just spatial resolution. The parabolic mirrors are formed on top of the micro-LEDs using lithography and deposition techniques. This allows the display to capture and reproduce the full angular information of a light field camera without needing user head tracking.

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Micro-LED 3D display module that provides 3D images without needing glasses. The module uses a specific arrangement of first and second micro-LED pixels with polarization films. The first pixels have a polarization film to pass images through the right lens of 3D glasses, while the second pixels have a different polarization film to pass images through the left lens. The first pixels are arranged in (2N-1) columns and the second pixels in (2N) columns. This layout allows 3D depth perception when viewing without glasses.

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Encapsulating micro LED displays to protect and enhance the performance of the LEDs. The encapsulation structure is a transparent plate on top of the micro LED array, with vias above each LED filled with a UV resin microlens that covers the LED. This protects the LEDs and allows control of the light emitted.

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MicroLED lighting devices with integrated optics to control and modulate the light output. The devices use microLEDs combined with tiny electrowetting cells. The electrowetting cells contain conductive and nonconductive fluids with different refractive indices. Applying voltage to the cell changes the shape of the fluid interface and thereby modulates the light beam from the microLED. The microLEDs themselves can collimate the light, and the electrowetting cells provide additional beam shaping.

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A 3D display that provides naked-eye 3D viewing without glasses or other aids. It uses a regular micro-LED display panel with an added layer of micro lenses on top. The micro lenses refract the light from the LEDs in different directions, creating separate left and right-eye views. This enables 3D display using only the naked eye.

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