A Rainbow for the Palm of Your Hand (IMAGE) University at Buffalo Caption This is a rainbow-colored grating, about 25 millimeters wide, under sunlight. Enlarged microscope images show the graded surface, with the black bars indicating a length of 10 microns. Credit University at Buffalo 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.