Color Variation (image) The Optical Society Caption This three-dimensional image of a small patch of a painted surface shows that the paint is non-uniform, consisting of four different layers. Credit Applied Research & Photonics. Usage Restrictions Include caption and credit. 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.