PSYCO367 Chapter Notes - Chapter 3: Retina Horizontal Cell, Absorption Spectroscopy, Purkinje Effect
Document Summary
Vision is based on visible light, which is a band of energy within the electromagnetic spectrum. Electromagnetic spectrum: a continuum of electromagnetic energy that is produced by electric charges. Energy in this spectrum can be described by its wavelength: distance between the peaks of the electromagnetic waves. Visible light: the energy within the electromagnetic spectrum that humans can perceive: 400 to 700 nm. Light enters through the pupil and is focused by the cornea and the lens to form sharp images of the object on the retina. Rods and cones, which contain light sensitive chemicals called visual pigments that react to light and trigger a electrical signal. Optic nerve: which conducts signals toward the brain. The cornea (transparent covering of the front of the eye, accounts for about 80% of the eyes focusing power. The lens supplies the remaining 20% of the eyes focusing power.