Commercially viable Light emitting diodes or LEDs date back almost fifty years, when red LEDs were used in calculator displays. The breakthrough in LED commercialization took place when the blue LED was developed by Isamu Akasaki, Hiroshi Amano, and Shuji Nakamura in the early 1990s, making white light possible. Over the last decade, rapid developments in LED package miniaturizations (mini LEDs) have been driven by direct emitting larger format displays and dynamic backlights for TVs and monitors. Smaller packages allow for more densely packed LEDs in the panels of direct emitting displays, hence a higher resolution. For dynamic TV and monitor backlights, a higher number of LEDs enables precise control for high-contrast images.
The next revolution will be micro LEDs, a necessary step towards direct emitting TVs and monitors. MicroLEDs are no longer used as backlights but as individual pixels emitting Red-Green-Blue (RGB) light directly without color filters and LCD light valves. There are many challenges in the industrializing of microLED consumer products. Sizes of micro LEDs can vary between 2um to 30um. Such dimensions are difficult to handle even in state-of-the-art pick and place processes.