Night vision: There’s an app for that

Krista D. Zanolli, contributing editor

A paper-thin device that uses energy-efficient organic LED technology similar to that found in flat-screen TV and laptop computer screens soon could be made into a night vision application for cell phone cameras.

“Really, this is a very inexpensive device,” said Franky So, a University of Florida researcher and professor of materials science and engineering. “Incorporating it into a cell phone might not be a big deal.”

Conventional night vision devices use massive amounts of electricity. The technology entails converting invisible infrared light photons into electrons via a photocathode. The electrons then are accelerated under high voltage and driven into a phosphorous screen, producing greenish images – the color to which the human eye is most sensitive – of objects not visible to the human eye in darkness. Turning photons into thousands of volts of electrons requires a vacuum tube similar to a cathode-ray tube. The vacuum tube is made of thick, heavy glass, which is why night vision goggles tend to be bulky and heavy.

As described in a recent issue of the journal Advanced Materials, So replaced the heavy glass with lighter, thinner plastic, eliminating the need for the vacuum tube. Co-author of the paper was Do Young Kim, a postdoctoral associate in materials science and engineering. The project was funded in part by DARPA.

The night vision device uses several layers of organic semiconductor thin-film materials and can range in diameter from a few millimeters to the size of a nickel.

“This device can convert any infrared image into a visible image and would weigh no more than a pair of eyeglasses,” So said in an interview with Discovery News. “Ten years ago, when people talked about putting cameras in cell phones, people asked: Why would you want to do that? Now you cannot find a cell phone without a camera. In the future, you might not be able to find a cell phone without night vision.”

So said that other applications could include night vision technology for car windshields or for standard eyeglasses for night use. He said his team plans to create cell phones that also can measure heat. A thermal vision application could, for example, check a patient’s body temperature for a fever or, if applied to a windshield, could help a driver detect and avoid pedestrians crossing the street.

His research also was funded by Nano-holdings LLC, a Rowayton, Conn.-based company that licenses and develops nano-energy discoveries in partnership with universities, scientists and DARPA.

A University of Florida startup, Nir-Vision, a portfolio company of Nanoholdings, was formed recently to further develop and commercialize the technology, which is expected to take about 18 months for practical applications.

krista.zanolli@photonics.com