Rods and Cones in the Human Eye (image) NIH/National Eye Institute Share Print E-Mail Caption This is a confocal microscope image of rod and cone photoreceptors in a human retina. Fluorescent probes have been used to identify rod photoreceptors (green) and cone photoreceptors and horizontal cells (red). Credit National Eye Institute 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.