Pillars on Raman-Sensing Chip (image) Princeton University, Engineering School Caption Micrograph of a sensor developed at Princeton for sensing Raman scattering. Pillars support metal components that gather light and amplify Raman signals, wavelengths of light that can be used to identify a substance. Credit Stephen Y. Chou Usage Restrictions Please credit Stephen Y. Chou 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.