Lighting a path for microLEDs beyond display technologies

The extreme luminance, high energy efficiency, low cost, and long lifetime of microLEDs make them ideal for various applications. As their active light emitting areas are scaled down with improved fabrication methods, these devices are primarily used to develop next-generation display technologies, such as augmented reality and virtual reality.

Kumar and Kymissis highlighted the non-display applications of microLEDs, such as projector systems, computational imaging, communication systems, and neural stimulation.

“This review is essential for readers who want to know the extent of possibilities that microLED technology offers beyond the much-anticipated display applications,” Kumar said. “This article covers a range of applications, but I am most excited about microLEDs’ future application in optogenetic stimulation and imaging.”

The use of microLEDs in computational imaging techniques, including structured illumination microscopy and targeted illumination, will enhance opportunities for large-scale neural monitoring and stimulation.

To use microLEDs as light sources in these non-display applications, their electrical and optical properties, such as efficiency, beam shape, light output power, and emission wavelengths, must be adjusted for optimal performance. The authors discussed the electro-optical characteristics required for different non-display applications, as well as fabrication and processing techniques used to achieve these characteristics and integrate microLEDs with advanced structures.

“We hope this review will create interest in the research community to look at microLEDs beyond traditional applications,” Kumar said. “Researchers working in other areas—such as photonic crystals, quantum dots, and more—may see unique applications that combine two technologies and design systems for improved efficiency and performance.”

Source: “MicroLED/LED electro-optical integration techniques for non-display applications,” by V. Kumar and I. Kymissis, Applied Physics Reviews (2023). The article can be accessed at https://doi.org/10.1063/5.0125103 .