Texas Tech University

MicroLED: Small Size, Big Impact

By: Kaitlyn Hale 

Hongxing Jiang and Jingyu Lin knew when they filed their patent more than 18 years ago that the future of LED will be micro-size. It just took the rest of the world more than a decade to catch up.

“Everybody else was working on normal size LEDs,” Lin said. “So, we thought there would be many applications by making it smaller.”

It's no surprise that such illuminating technology has come from this power couple. Married for 35 years, Jiang and Lin moved their research group and microLED research to Texas Tech in 2008. Now, they are both Horn professors in the Department of Electrical and Computer Engineering, as well as co-directors of the Center of Nanophotonics. Each researcher has more than 400 publications.

Now, the microLED technology they invented is opening doors to new innovations, from next generation microLED large screen TVs to wearable and mobile displays.

Micro-size Light Emitting Diodes (MicroLEDs)

Originally invented while Jiang and Lin were at Kansas State University, “Micro-size LED and detector arrays for mini-displays, hyperbright light emitting diodes, lighting, and UV detector and imaging sensor applications” were first targeted for lighting and microdisplays, Jiang said. 

Current LED TVs are actually liquid-crystal displays (LCDs) that are backlit with LED lights, Lin said. Unlike traditional LEDs, microLEDs produce their own light and are small enough that multiple microLEDs of three primary colors can fit in one pixel, producing a much better picture than traditional technology.

“For the next generation microLED large TVs, you have millions of tiny pixels,” Jiang said. “Each pixel comes with three microLEDs, one blue, one green and one red. Because they're so tiny, they can give you a very high resolution and contrast, leading to more beautiful images. They're also very bright, and the dark areas are really dark. In the old technology, the dark areas of a display are not really as dark because some light still leaks through.”

MicroLED displays last longer and can operate in temperatures between minus 150 degrees to 250 degrees Fahrenheit. They also are more shock resistant and produce light more efficiently and so use less energy than current LED TV and display technologies. This means that not only are microLED smart phone displays brighter, but they use less energy and require charging less frequently.  Combined with its fast turn on/off speed, microLEDs are proving to be a lucrative piece within the tech industry, including applications in augmented reality (AR), virtual reality (VR) and three-dimensional (3D) displays. 

The microLED market is estimated to become a multi-billion dollar industry by 2025, which has led to the creation of thousands of jobs with the potential for thousands more in the coming years. Technology giants like Apple, Samsung, Sony, LG, Huawei and Google are all racing to use microLEDs for their next-generation TVs and mobile and wearable devices.

Projecting the Future

Eighteen years ago, Jiang and Lin imagined microLEDs could transform wearable tech and screen displays. Today, they know the technology can go well beyond that.

“It's going to open a lot of new products consumers have never seen before,” Lin said.

Jiang and Lin can see a time, eventually, when microLED technology could shrink and eliminate a computer or phone screen altogether. “This technology can also be used for image projection. You can display all the information on a wall, on a window, on a car windshield,” Jiang said, “Imagine a computer shrinks to a pen that can project the images.”

Lin said right now screen size really limits what can be done with computers. Computers continue to shrink, but the screen can never be smaller than what the average consumer can comfortably see. MicroLEDs and their ability to project anywhere solves that problem.

MicroLEDs have also allowed developers to think larger.  In 2018, Samsung unveiled its first microLED television, “The Wall” 4K TV, that measures 146-inches. Additionally, microLEDs are the most suitable technology for the emerging 3D and virtual reality applications. 

Outside of the entertainment industry, microLEDs are starting to be studied for their potential medical applications. Lin said microLEDs are close to the size of a neuron, which could have an impact on how some illnesses are monitored and treated.

“People are researching how to use this technology to control specific neurons,” Lin said. “So eventually it can be adapted to medical applications for controlling pain or seizures.”

As the world begins to recognize and build upon microLEDs, Jiang said he and Lin are very satisfied with their innovation. 

“In most research, you don't see this kind of excitement and outcome or getting it to commercial products within your lifetime,” Jiang said. “The microLED technology looks like it will have a very big impact to the market for many different applications, so it's really satisfying.”