Chapter 2: The First Steps in Vision: From Light to Neural Signals. V1 Flashcards
Wave
An oscillation that travels through a medium by transferring energy from one particle or point to another without causing any permanents displace of the medium.
Photon
A quantum of visible light or other form of electromagnetic radiation demonstrating both particle and wave properties.
Absorb
To take up energy and not transmit it at all
Scatter
To disperse light in an irregular fashion.
Reflect
To redirect something that strikes a surface back towards point of origin
transmit
To convey something from one place to another
Refract
- To alter the course of a wave of energy that passes into something from another medium, as water does to light entering it from the air.
- To measure the degree of refraction in a lens/eye.
Cornea
Transparent window into eyeball
Transparent
Allowing light to pass through with no interruption, so that objects on the other side can be clearly seen.
Aqueous Humor
Watery fluid in anterior chamber of eye.
Crystalline Lens
Lens inside eye that enables changing of focus
Pupil
Dark, circular opening at the center of the iris in the eye, where light enters the eye.
Iris
Colored part of eye, consisting of muscular diaphragm surrounding the pupil.
Vitreous humor
Transparent Fluid that fills the vitreous chamber in the posterior part of eye.
Retina
A light-sensitive membrane in the back of the eye that contains rods and cones, which receive an image from the lens and send it to the brain through the optic nerve.
Accommodation
The process by which the eye changes its focus (in which the lens gets fatter as gaze is directed toward nearer objects).
Presbyopia
Old sight. Loss of near vision because of insufficient accommodation.
Cataract
An opacity of the crystalline lens.
Emmetropia
No refractive error because power of eye is perfectly matched to length of eyeball.
Myopia
Nearsightedness, light entering eye is focused in front of retina and distant objects cannot be seen sharply.
Hyperopia
Farsightedness, light entering eye is focused behind the reitna and accommodation is required in order to see near objects clearly.
Astigmatism
Visual defect caused by unequal curving of one or more of the refractive surfaces of the eye, usually cornea.
Transduce
To convert from one form of energy to aother
Fundus
Back layer of retina, what eye doctor sees though scope.