Pelli-Robson Chart (image) University of Rochester Share Print E-Mail Caption This is a Pelli-Robson chart showing decreasing contrast from upper left to lower right. True contrast varies between monitors. Credit University of Rochester Usage Restrictions None Share Print E-Mail 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.