A nano-patterned GaN/InGaN quantum well metasurface with high unidirectional photoluminescence that can be used for the development of compact LEDs with high directional emissions.
GaN light emitting diodes (LEDs) are state of the art solutions for display applications. Imparting directionality or collimating the light coming out of these LEDs is an essential requirement for efficient implementation in display and lighting devices. Controlling the direction of spontaneous emission is an extremely challenging and long sought-after property from light emitting diodes (LEDs). Various bulk optical packaging, nano-patterning and surface roughening techniques have been used previously to efficiently collect and collimate the light coming out of LEDs, with accompanying losses in the extraction of light. All of these current approaches require external bulk optical components (e.g. lenses) to ultimately collimate the light extracted from the LEDs, which is not a feasible solution for thin free-form display elements currently in development.
Researchers at the University of California, Santa Barbara have created a nano-patterned GaN/InGaN quantum well metasurface with high unidirectional photoluminescence that can be used for the development of compact LEDs with high directional emissions. The optical functionality of directing light is integrated directly into the semiconductor structure, which is particularly advantageous in the development of ultra-compact optical components for the virtual, augmented, and mixed reality space that requires high directional and highly efficient light sources, including mobile near-eye augmented reality display. This technology offers unique advantages in display efficiency. The unidirectional emission greatly extends the battery life of AR-wearable devices and the highly polarized light can be combined with LCDs to yield a 3x improvement over existing non-polarized LEDs.
photoluminescense, indfeat, indled, light-emitting diodes, microLED, augmented reality, virtual reality, mixed reality, display