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Unformatted text preview: Acuity
• Retina contains approximately 100 million photoreceptors and 1
million ganglion cells – CONVERGENCE!!!
• Peripheral retina: convergence = 100:1 periphery--100:1 • Fovea: convergence can be 1:1 photorecptros to ganglion cells fovea---1:1
Vs. More convergence →
larger receptive field and
lower acuity (resolution) Less convergence →smaller
receptive field and higher
acuity (resolution) eccentricity is how far we are away from the fovea of the eye Visual Acuity it just shows you the frequency of rods and cones in relation to
where you are in the retina optic disc is a blind spot!!!----KNOW THIS !!!!!! Blind spot X http://faculty.washington.edu/chudler/chvision.html 6
! So what kind of information
does visual scene provide?
Depth Perception interposition----not physilogically determines Depth Perception --blocking means infront Interposition – an object
blocking part of another
object is nearer just know these depth cues----like 5 of them i think--its heuristic knowledge- we bring in cognition now with this. it not
physiological its knowlegde wehave through living in the world. Depth Perception Relative Size – objects of
similar sizes at varying distance
cast different retinal image sizes 7
! Depth Perception Luminance Gradient –
brighter is perceived
nearer Shadows – three dimensional
form and source of light Depth Perception Linear Pe...
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This document was uploaded on 03/28/2014 for the course KNES 385 at Maryland.
- Fall '08