We propose a methodology to mitigate angular color variation in full-color micron-scale LED arrays. By simulating light field distribution for red (AlGaAs) and green/blue (GaN) light across various RGB micro-LED sizes, we can select matching light field patterns for RGB chips, reducing angular color variation from 0.0201 to 0.
View Article and Find Full Text PDFA simulation scheme was developed to explore the light distribution of full-color micron-scale light-emitting diode (LED) arrays. The influences of substrate thickness, patterning, and cutting angle of the substrate on several important features, such as light field pattern, light extraction efficiency, and color variation, were evaluated numerically. An experiment was conducted; the results were consistent with simulation results for a 225 × 125 µm miniLED and those for an 80 × 80 µm microLED.
View Article and Find Full Text PDFFar-field distributions of GaN-based photonic crystal (PhC) film-transferred light-emitting diodes (FT-LEDs) were investigated. The thickness of the device is about 840 nm. The emission wavelength is around 520 nm.
View Article and Find Full Text PDFAngular distribution of light diffracted out of the plane of two-dimensional photonic crystals (PhC) has been studied in the azimuthal direction with a specially designed waveguide structure. The optical images of the light extraction patterns from the guided photoluminescence light are obtained with laser excitation in the center of the annual structure made on GaN multilayer. For increasing lattice constant, symmetric patterns with varying number of petals according to the symmetry of the PhC are observed.
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