Low-repetition-rate laser excites multiple fluorescence signals. (IMAGE) SPIE--International Society for Optics and Photonics Caption Low-repetition-rate laser excites multiple fluorescence signals. Credit Courtesy of T. Qiao (HKU). 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.