At present, a review has been conducted on the history, definition, and technical challenges of Micro LED display technology, with a focus on summarizing the technical challenges of Micro LED in the engineering field. Finally, the future development direction of Micro LED technology has been discussed. Micro LEDs still face technological challenges in terms of chips, massive transfer, and full color conversion. However, their outstanding characteristics such as high resolution, fast response, low energy consumption, and long lifespan can meet the needs of ultra small and ultra large displays, such as virtual/enhanced displays and electronic billboards. They have shown enormous application potential and have attracted extensive research in academia and industry.

Micro LED displays utilize micron sized inorganic LED devices as luminescent pixels to achieve active emission matrix display. From the perspective of display technology principles, Micro LED, organic light-emitting diode OLED, and quantum dot light-emitting diode QLED belong to active light-emitting display technology. However, the difference is that Micro LED displays use inorganic GaN and other LED chips, which have excellent luminous performance and long lifespan. Due to the excellent performance and potential application value of Micro LEDs, there has been a wave of related technological research in the academic community since their proposal.

With the continuous development of Micro LED display technology, its industrialization has also received increasing attention. Apple, Samsung, Sony, LG, CSOT, BOE Technology and other companies have joined the development of Micro LED display. In addition, many start-up companies engaged in Micro LED display technology have also been established, such as Ostendo, Luxvue, PlayNitride, etc.

Starting from Apple’s acquisition of Luxvue in 2014, Micro LED display technology has entered a rapid development stage. After 2018, it entered an explosive period. Meanwhile, domestic terminal and chip manufacturers have also joined the Micro LED camp. Although the display application prospects of Micro LED are gradually becoming clear, there are still many technical challenges to be solved at this stage.