Piezo-Phototronic LED (1 of 2) (image) Georgia Institute of Technology Caption Researchers have developed a sensor device that converts mechanical pressure -- from a signature or a fingerprint -- directly into light signals that can be captured and processed optically. Shown is Professor Zhong Lin Wang of the Georgia Institute of Technology. Credit Georgia Tech Photo: Gary Meek Usage Restrictions None Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.