Wolfram Demonstrations Projecthttp://demonstrations.wolfram.com/An Open Resource of Interactive Mathematica VisualizationsCopyright 2009 Wolfram Demonstrations Project & ContributorsOptical Model of the Human Eyehttp://demonstrations.wolfram.com/OpticalModelOfTheHumanEye/]]>http://demonstrations.wolfram.com/OpticalModelOfTheHumanEye/Lens Doubletshttp://demonstrations.wolfram.com/LensDoublets/]]>http://demonstrations.wolfram.com/LensDoublets/