PSYB51H3 Chapter Notes - Chapter 3: Retina, Spatial Frequency, Visual Angle
Document Summary
Chapter 3- spatial vision: from spots to stripes. Acuity: the smallest spatial detail that can be resolved. Cycle: for a grating, a pair consisting of one dark bar and one bright bar. Ex. when you"re looking at a picture of black bars on white paper, if there are 25 cycles you will see 25 black bars. Visual angle: the angle subtended by an object at the retina. (an example picture on page 57) Sine wave grating: a grating with a sinusoidal luminance profile. Aliasing: misperception of a grating due to undersampling. This could happen when the lines in a gradient are so thin that one photoreceptor covers the white and black portion. This is when we misperceive the cycles to be longer than they really are. *high contrast sine wave gratings can be distinguished from a uniform gray field, as long as adjacent pairs of light or dark stripes are separated by at least 1 arc minute of visual angle.
