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  • 2013-03-06 15:40:00
  • Article ID: 600023

Student Innovator at Rensselaer Polytechnic Institute Seeks Brighter, Smarter, and More Efficient LEDs

  • Credit: Rensselaer

    Rensselaer Polytechnic Institute student Ming Ma has developed a new method to manufacture light-emitting diodes (LEDs) that are brighter, more energy efficient, and have superior technical properties than those on the market today. His patent-pending invention holds the promise of hastening the global adoption of LEDs and reducing the overall cost and environmental impact of illuminating our homes and businesses. For this innovation, Ma, a doctoral student in the Department of Materials Science and Engineering, has been named the winner of the prestigious 2013 $30,000 Lemelson-Rensselaer Student Prize.

Michael Mullaney

518-276-6161

mullam@rpi.edu

News from Rensselaer Polytechnic Institute

March 5, 2013

www.rpi.edu/news

$30,000 Lemelson-MIT Collegiate Student Prizes Awarded to Inventive Students at Three Leading Universities

Troy, N.Y.—Rensselaer Polytechnic Institute student Ming Ma has developed a new method to manufacture light-emitting diodes (LEDs) that are brighter, more energy efficient, and have superior technical properties than those on the market today. His patent-pending invention holds the promise of hastening the global adoption of LEDs and reducing the overall cost and environmental impact of illuminating our homes and businesses.

For this innovation, Ma, a doctoral student in the Department of Materials Science and Engineering, has been named the winner of the prestigious 2013 $30,000 Lemelson-Rensselaer Student Prize. He is among the three 2013 $30,000 Lemelson-MIT Collegiate Student Prize winners announced today.

“For more than 175 years, Rensselaer has produced some of the world’s most successful engineers and scientists, explorers and scholars, innovators and entrepreneurs. Doctoral student Ming Ma, with his groundbreaking invention of GRIN LEDs, honors and continues this tradition of excellence,” said David Rosowsky, dean of the School of Engineering at Rensselaer. “Rensselaer and the School of Engineering offer a hearty congratulations to Ming for his achievement. We also applaud all of the winners, finalists, and entrants of the Lemelson-MIT Collegiate Student Prize for using their talent and passion to engineer a better world and a better tomorrow.”

Ma is the seventh recipient of the Lemelson-Rensselaer Student Prize. First given in 2007, the prize is awarded annually to a Rensselaer senior or graduate student who has created or improved a product or process, applied a technology in a new way, redesigned a system, or demonstrated remarkable inventiveness in other ways.

“Invention is critical to the U.S. economy. It is imperative we instill a passion for invention in today’s youth, while rewarding those who are inspiring role models,” said Joshua Schuler, executive director of the Lemelson-MIT Program. “This year’s Lemelson-MIT Collegiate Student Prize winners and finalists from the Massachusetts Institute of Technology, Rensselaer Polytechnic Institute, and the University of Illinois at Urbana-Champaign prove that inventions and inventive ideas have the power to impact countless individuals and entire industries for the better.”

For videos and photos of Ma and other award finalists, please visit: www.eng.rpi.edu/lemelson

Seeking Brighter, Smarter LEDs

Conventional incandescent and fluorescent light sources are increasingly being replaced by more energy-efficient, longer-lived, and environmentally friendlier LEDs, but LEDs still suffer from challenges related to brightness, efficiency, and performance With his project, “Graded-refractive-index (GRIN) Structures for Brighter and Smarter Light-Emitting Diodes,” Ma faced these problems head-on and tackled a fundamental, well-known technical shortcoming of LED materials.

LEDs are hampered by low light-extraction efficiency—or the percentage of produced light that actually escapes from the LED chip. Currently, most unprocessed LEDs have a light-extraction efficiency of only 25 percent, which means 75 percent of light produced gets trapped within the device itself.

One solution that has emerged is to roughen the surface of LEDs, in order to create nanoscale gaps and valleys that enable more light to escape. While surface roughening leads to brighter and more efficient light emission, the roughening process creates random features on the LED’s surface that do not allow for a complete control over other critical device properties such as surface structure and refractive index.

Freeing Trapped Light with GRIN LEDs

Ma’s solution to this problem was to create an LED with well-structured features on the surface to minimize the amount of light that gets reflected back into the device, and thus boost the amount of light emitted. He invented a process for creating LEDs with many tiny star-shaped pillars on the surface. Each pillar is made up of five nanolayers specifically engineered to help “carry” the light out of the LED material and into the surrounding air.

Ma’s patent-pending technology, called GRIN (graded-refractive-index) LEDs, has demonstrated a light-extraction efficiency of 70 percent, meaning 70 percent of light escaped and only 30 percent was left trapped inside the device—a huge improvement over the 25 percent light-extraction efficiency of most of today’s unprocessed LEDs. In addition, GRIN LEDs also have controllable emission patterns, and enable a more uniform illumination than today’s LEDs.

Overall, Ma’s innovation could lead to entirely new methods for manufacturing LEDs with increased light output, greater efficiency, and more controllable properties than both surface-roughened LEDs and the LEDs currently available in the marketplace.

Impactful Researcher

Ma joined Rensselaer in 2008 as a member of Professor E. Fred Schubert’s research team. In his time at Rensselaer, Ma has been the first author on five research papers, published in Applied Physics Letters, Journal of Applied Physics, and Optics Express, and co-author of several studies in other journals. He is also a reviewer for Optics Letters and Optics Express.

“Ming Ma is an outstanding student—strongly motivated, creative, intelligent, and highly skilled,” said Schubert, the Wellfleet Senior Professor in the Future Chips Constellation at Rensselaer and a faculty member of the university’s Department of Electrical, Computer, and Systems Engineering and Department of Physics, Applied Physics, and Astronomy. “Ming’s technical accomplishments are innovative, and have had a significant impact on the LED materials research community. The innovation of GRIN LEDs should not be underestimated—Ma’s invention is the first viable approach for high-efficiency LEDs with a controllable far-field emission pattern. This is an important development for LED lighting, and it is already capturing the attention of industry.”

Growing up in Jiangxi Province in southeast China, Ma fostered an early love of science. This fascination was fostered by his father, a newspaper editor, and his mother, a mechanical engineer at a pharmaceutical manufacturer. Ma became interested in advanced materials as an undergraduate student at Fudan University in Shanghai, which inspired him to study LEDs as a graduate student at Rensselaer.

Upon completing his doctoral degree from Rensselaer later this year, Ma plans to continue researching materials and LEDs in academia or industry.

Lemelson-MIT Collegiate Student Prizes

Winners of the $30,000 Lemelson-MIT Collegiate Student Prize were also announced today at their respective universities:

• Lemelson-MIT Student Prize Winner Nikolai Begg has developed medical devices to make “puncture access” medical procedures, such as laparoscopic surgeries and epidurals, less risky. Many minimally invasive procedures use puncture access devices that plunge forward after breaking through tissue. Begg’s “force sensing” mechanism has a blade that retracts the moment it passes through tissue, significantly lowering the risk of damage to underlying organs when creating a pathway into the patient’s body.

• Lemelson-Illinois Student Prize Winner Eduardo Torrealba has created Plant Link, which monitors the moisture needs of specific plants and can deliver water on an as needed basis using smart valves. The evolution of this wireless product will make agricultural water resource management easier and more affordable than ever on a global scale. Ranging from home lawns and gardens to farms in emerging economies, this technology has a huge potential to impact the sustainability and costs of water usage.

About the $30,000 Lemelson-Rensselaer Student Prize

The $30,000 Lemelson-Rensselaer Student Prize is funded through a partnership with the Lemelson-MIT Program, which has awarded the $30,000 Lemelson-MIT Student Prize to outstanding student inventors at MIT since 1995.

About The Lemelson-MIT Program

Celebrating innovation, inspiring youth

The Lemelson-MIT Program celebrates outstanding innovators and inspires young people to pursue creative lives and careers through invention.

Jerome H. Lemelson, one of U.S. history’s most prolific inventors, and his wife, Dorothy, founded the Lemelson-MIT Program at the Massachusetts Institute of Technology in 1994. It is funded by The Lemelson Foundation and administered by the School of Engineering. The Lemelson Foundation uses the power of invention to improve lives by inspiring and enabling the next generation of inventors and invention-based enterprises to promote economic growth in the United States and social and economic progress for the poor in developing countries. http://web.mit.edu/invent/

Read about past winners of the $30,000 Lemelson-Rensselaer Student Prize:

• Student Innovator Uses Graphene Foam To Detect Subtle Traces of Hazardous Gases and Explosives

Fazel Yavari’s graphene innovation is a new sensor to detect extremely small quantities of hazardous gases

http://news.rpi.edu/update.do?artcenterkey=3005

• Student Innovator Uses Sound Waves, T-Rays for Safer Detection of Bombs and Other Dangerous Materials

Benjamin Clough’s invention increases distance between first responders and potential threats

http://news.rpi.edu/update.do?artcenterkey=2840

• Helping Hydrogen: Student Inventor Tackles Challenge of Hydrogen Storage

Javad Rafiee’s graphene innovation could lead to more efficient hydrogen-powered vehicles

http://news.rpi.edu/update.do?artcenterkey=2690

• Student Developer of Versatile “G-gels” Wins $30,000 Lemelson-Rensselaer Prize

Yuehua “Tony” Yu’s innovation could lead to new medical devices, drug-delivery technologies

http://news.rpi.edu/update.do?artcenterkey=2538

• Student Develops New LED, Wins $30,000 Lemelson-Rensselaer Prize

Martin Schubert’s polarized LED could improve LCD displays, save energy

http://news.rpi.edu/update.do?artcenterkey=2406

• Handheld “T-Ray” Device Earns New $30,000 Lemelson-Rensselaer Student Prize

Brian Schulkin’s “Mini-Z” spots cracks in space shuttle foam, detects tumors in tissue

http://news.rpi.edu/update.do?artcenterkey=1944

Contact

Michael Mullaney

Rensselaer Polytechnic Institute

Troy, NY

518-276-6161

mullam@rpi.edu

Visit the Rensselaer research and discovery blog: http://approach.rpi.edu

Follow us on Twitter: www.twitter.com/RPInews

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