CIS 3365 Lecture Notes - Lecture 11: Mach Bands, Receptive Field, Retina

• School: University of Houston
• Department: Computer Information Systems
• Course: CIS 3365
• Professor: Xuqing Wu

Document Summary

Eye is like a camera: eye has a lens (obeys laws of objects, no flexibility left at age of ~60) and retina is like a film. Acuity and contrast sensitivity: simple acuity (maximal at fovea, about 1") Superacuities (achieved by integrating the output of several retinal receptors, accuracies up to 10"") Contrast sensitivity (acuity is lower at lower contrasts; sensitivity to high frequencies and low contrasts falls by age) The retina is like the film in camera. Roughly: retina must be able to work at varying light levels , all constant stimuli are ignored. For example, contrast is the perception of difference in the brightness. Perceptual contrast and physical contrast (actual difference in the luminance) does not necessarily correspond to each other. Difference of gaussians model fields when light falls at the center of receptive field it emits pulses. Off center of receptive field it emits pulses at lower,