Define the term visual accommodation

Question

Define the term visual accommodation?

Answer 1

Visual accommodation is the phenomenon of varying curvature of crystalline lens to form possible variation of its refractivity to adjust the images of objects precisely onto the retina. Visual accommodation is accomplished by the action of ciliary muscles.

The nitid vision based on the visual accommodation as, when the images are not projected onto the retina however in front or behind it, they will emerge blurred. The closer an object is, more ciliary muscles should compress the crystalline lens (raising its curvature); the more distant an object is, more the ciliary muscles should relax.