Terahertz Imaging (IMAGE) California Institute of Technology Caption This is a metal key tucked inside an envelope. Inset: the terahertz image obtained with the silicon chip. Credit Kaushik Sengupta/Caltech Usage Restrictions None License Licensed content 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.