PSYB51H3 Chapter Notes - Chapter 2: Strabismus, Angular Distance, Thalamus
Document Summary
Contrast: the difference in luminance btwn an object & the background, or btwn lighter and darker parts of the same object. Acuity: the mallest spatial detail that can be resolved at 100% contrast. Cycle: for a grating, a pair consisting of one dark bar and one bright bar: repetition of black and white stripe. Visual angle: the angle subtended by an object at the retina: lines going from top to bottom, or left to right (depending on orientation of stripes) of a cycle on a page. Passes thru the centre of the lens, and ends on the retina: to calculate visual angle. Size of cycle / viewing distance where you can just barely make out the orientation of the gratings. Then take the arctenngent of the ratio. Humans w v good vision can resolve gratings when one cycle subtends an angle of approx. 1 minute of arc: this resolution acuity represents one of the fundamental limits of spatial vision.
