Waveguide (IMAGE) Vienna University of Technology Caption The light can travel back and forth in the two closely spaced waveguides (red and blue) and is partially reflected at their ends. Credit TU Wien Usage Restrictions none License Original 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.