Eyes detect light through a process called vision. When light enters the eye, it first passes through the cornea, a clear, protective outer layer. The cornea refracts the light and directs it to the pupil, which controls the amount of light entering the eye. The light then reaches the retina, a thin layer of tissue at the back of the eye, where specialized cells called photoreceptors convert the light into electrochemical signals that are sent to the brain for interpretation.
