Eye

An eye is a sensory organ that enables a human to perceive light. It is round. Humans generally have two eyes. An eye has a lens and a retina. The retina is the image sensor of the eye. The retina is largely a flat but curved surface that has little depth.

An eye can focus.

The eyes give signals to the brain, which picks up on depth cues and provides us with depth perception.

There are multiple ways to conceptually represent a human eye, particularly in the optics of the eye.

Eyes connect to the brain using the optical nerve.

The optical center of the eye is not the same as the rotational center, giving rise to ocular parallax, which has been accounted for by some researchers who have built an eye tracking system to automatically change the rendering of a VR scene slightly according to someone's gaze.