Earns highest degree in lighting field at RPI

By Jessica M. Pasko
The Record

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TROY — A Shanghai native is the first person to graduate from the doctoral program at Rensselaer Polytechnic Institute’s Lighting Research Center, and her work could eventually lead to reducing the amount of electricity consumption that lighting accounts for each year.

Yiting Zhu graduated last month with a doctorate in architectural science with a concentration in lighting and is staying on as a faculty member at the center, where she will continue her research into light-emitting diodes, better known as LEDs.

Zhu’s degree is the highest available in the field of lighting, and it’s the first of its kind in the lighting industry, according to RPI officials. Until a few years ago, the center only offered one- and two-year master’s program, but a Ph.D. program was launched a few years ago to take these studies to an even higher level. While Zhu is the first to graduate from the program, seven other students are currently enrolled in doctoral studies at the lighting research center.

Zhu came to RPI for her master’s degree after earning a bachelor’s degree in illumination engineering from Fudan University in Shanghai, China.

“I’ve always been very good in science and engineering,” said Zhu. “I always wanted to go to school for engineering.”

The college she chose didn’t have a lot of engineering options, which led her to the illumination program. From there, she decided to pursue a master’s in the field at RPI. The 27-year-old now lives in Troy with her husband, who is pursuing his doctorate in electrical engineering at RPI.

“RPI’s lighting program was cutting-edge and it had a worldwide reputation,” she said. “It was the premier lighting research center.”

The Lighting Research Center at RPI began in 1988 as a place to investigate lighting issues and education the next generation of lighting leaders, and it’s widely-known as the leading university-based research center devoted to lighting. The center’s focus is on advancing the effective use of light, and programs include laboratory testing of lighting products and real-world demonstration and evaluation of lighting products and designs. The center collaborates with numerous industry partners and municipalities on a wide variety of projects. Projects there don’t just focus on commercial applications for light, however. Work is also being done in areas such as using ultraviolet lights to disinfect water as well as light therapy, which involves using exposure to specific wavelengths of light to treat ailments such as acne, neonatal jaundice, seasonal affective disorder and delayed sleep phase syndrome.

Zhu’s research focuses on solid-state lighting, a type of lighting that uses light-emitting diodes as sources of illumination rather than electrical filaments, gas or plasma. Specifically, she’s been working with what are more commonly known as LEDs, which use semiconductors, with an emphasis on using phosphor technology to improve the color quality and efficacy of white LEDs. To put it more simply, the problem with current white LED lighting is that it often appears more like blue-ish light, which hampers the use of this type of lighting for many applications.

The best commercial white LED lighting systems provide more than twice the luminous efficacy of incandescent bulbs, which can add up to a lot of energy savings, but researchers believe they can be made even better. LEDs have been around for more than 40 years, but until recently were only used in electronic devices as indicator lamps. Nowadays, they’re commonly used in signal devices such as traffic light and exit signs. Researchers at places like RPI’s lighting research center are now working to make them useful for general illumination, both on the residential and commercial level.

LEDs also last much longer than regular incandescent light bulbs. LED can last 50,000 hours, as opposed to the approximately 1,000-hour lifespan of an incandescent light bulb. They’re also smaller and more durable, making them ideal for things like freezer case lighting. Though compact fluorescent lights are also more efficient than incandescent bulbs, researchers feel that the possibilities of LEDs are much more extensive. Getting costs down is another factor in the lights’ commercial viability.

Increasing the efficiency of the lighting we use, while also maximizing the efficacy and reducing energy costs, is a major end goal of research like Zhu’s. The U.S. Energy Information Administration estimates that in 2007, lighting accounted for 14 percent of total electricity consumption in the U.S. In the residential sector, lighting made up 15 percent of all residential electricity consumption, while it accounted for 23 percent of commercial sector electricity consumption.

Creating white light with LEDs can be done in one of two ways – either by combining red, green and blue LED lights in just the right way, or by using a phosphor coating over a blue LED. One downfall of the latter method is that phosphor based LEDs have a lower efficiency. These issues are the crux of Zhu’s research. There’s a lot that goes into it, and it can be very complicated. Some of this work was begun during her master’s degree program.

“I like to take challenges,” said Zhu of her decision to pursue a doctorate. “This research is very interesting…It’s a rapidly growing field because of the energy efficiency issues.”

In her new position at RPI as the manager of technology evaluation and testing, Zhu will continue her research while also working closely with manufacturers to ensure her technical efforts support the integration of LEDs into every day applications. That will involve a lot of testing and evaluations in real-world environments. She’ll also be working to test the lights as part of a system, and help test available products in hopes of making improvements.

Jessica M. Pasko can be reached at 270-1288 or by e-mail at jpasko@troyrecord.com.

earns highest degree in lighting field at RPI

Jessica M. Pasko

The Record

TROY — A Shanghai native is the first person to graduate from the doctoral program at Rensselaer Polytechnic Institute’s Lighting Research Center, and her work could eventually lead to reducing the amount of electricity consumption that lighting accounts for each year.

Yiting Zhu graduated last month with a doctorate in architectural science with a concentration in lighting and is staying on as a faculty member at the center, where she will continue her research into light-emitting diodes, better known as LEDs.

Zhu’s degree is the highest available in the field of lighting, and it’s the first of its kind in the lighting industry, according to RPI officials. Until a few years ago, the center only offered one- and two-year master’s program, but a Ph.D. program was launched a few years ago to take these studies to an even higher level. While Zhu is the first to graduate from the program, seven other students are currently enrolled in doctoral studies at the lighting research center.

Zhu came to RPI for her master’s degree after earning a bachelor’s degree in illumination engineering from Fudan University in Shanghai, China.

“I’ve always been very good in science and engineering,” said Zhu. “I always wanted to go to school for engineering.”

The college she chose didn’t have a lot of engineering options, which led her to the illumination program. From there, she decided to pursue a master’s in the field at RPI. The 27-year-old now lives in Troy with her husband, who is pursuing his doctorate in electrical engineering at RPI.

“RPI’s lighting program was cutting-edge and it had a worldwide reputation,” she said. “It was the premier lighting research center.”

The Lighting Research Center at RPI began in 1988 as a place to investigate lighting issues and education the next generation of lighting leaders, and it’s widely-known as the leading university-based research center devoted to lighting. The center’s focus is on advancing the effective use of light, and programs include laboratory testing of lighting products and real-world demonstration and evaluation of lighting products and designs. The center collaborates with numerous industry partners and municipalities on a wide variety of projects. Projects there don’t just focus on commercial applications for light, however. Work is also being done in areas such as using ultraviolet lights to disinfect water as well as light therapy, which involves using exposure to specific wavelengths of light to treat ailments such as acne, neonatal jaundice, seasonal affective disorder and delayed sleep phase syndrome.

Zhu’s research focuses on solid-state lighting, a type of lighting that uses light-emitting diodes as sources of illumination rather than electrical filaments, gas or plasma. Specifically, she’s been working with what are more commonly known as LEDs, which use semiconductors, with an emphasis on using phosphor technology to improve the color quality and efficacy of white LEDs. To put it more simply, the problem with current white LED lighting is that it often appears more like blue-ish light, which hampers the use of this type of lighting for many applications.

The best commercial white LED lighting systems provide more than twice the luminous efficacy of incandescent bulbs, which can add up to a lot of energy savings, but researchers believe they can be made even better. LEDs have been around for more than 40 years, but until recently were only used in electronic devices as indicator lamps. Nowadays, they’re commonly used in signal devices such as traffic light and exit signs. Researchers at places like RPI’s lighting research center are now working to make them useful for general illumination, both on the residential and commercial level.

LEDs also last much longer than regular incandescent light bulbs. LED can last 50,000 hours, as opposed to the approximately 1,000-hour lifespan of an incandescent light bulb. They’re also smaller and more durable, making them ideal for things like freezer case lighting. Though compact fluorescent lights are also more efficient than incandescent bulbs, researchers feel that the possibilities of LEDs are much more extensive. Getting costs down is another factor in the lights’ commercial viability.

Increasing the efficiency of the lighting we use, while also maximizing the efficacy and reducing energy costs, is a major end goal of research like Zhu’s. The U.S. Energy Information Administration estimates that in 2007, lighting accounted for 14 percent of total electricity consumption in the U.S. In the residential sector, lighting made up 15 percent of all residential electricity consumption, while it accounted for 23 percent of commercial sector electricity consumption.

Creating white light with LEDs can be done in one of two ways – either by combining red, green and blue LED lights in just the right way, or by using a phosphor coating over a blue LED. One downfall of the latter method is that phosphor based LEDs have a lower efficiency. These issues are the crux of Zhu’s research. There’s a lot that goes into it, and it can be very complicated. Some of this work was begun during her master’s degree program.

“I like to take challenges,” said Zhu of her decision to pursue a doctorate. “This research is very interesting…It’s a rapidly growing field because of the energy efficiency issues.”

In her new position at RPI as the manager of technology evaluation and testing, Zhu will continue her research while also working closely with manufacturers to ensure her technical efforts support the integration of LEDs into every day applications. That will involve a lot of testing and evaluations in real-world environments. She’ll also be working to test the lights as part of a system, and help test available products in hopes of making improvements.

Jessica M. Pasko can be reached at 270-1288 or by e-mail at jpasko@troyrecord.com.