When you look at an object, light enters the eye through your pupil. Light passing through the lens is bent (refracted) and focused onto the retina in the back of the eye. The job of the lens is to make sure the light comes into sharp focus. The retina gives us our wide field of vision. It contains millions of rod and cone cells that convert light energy into electrical signals, which are then sent to the brain via the optic nerve. The macula, an area within the retina, allows for focusing on fine detail and the fovea, a small area within the macula, manages central vision. The remaining components of the eye include protective layers (such as the conjunctiva and sclera), nourishing blood vessels (such as the choroid) and systems for managing eye fluid and pressure (such as the Trabecular Meshwork/Canal of Schlemm).

Aqueous
The clear fluid occupying the space between the cornea and the lens of the eye. The aqueous nourishes the lens and epithelial cells. back

Choroid
The choroid is a layer of blood vessels that lies between the retina and sclera. These blood vessels nourish the back of the eye. back

Conjunctiva
The conjunctiva is the thin, transparent tissue that covers the outer surface of the eye. back

Cornea
The cornea is a clear, dome-shaped outer coating that covers the front of the eye. Light passes through the cornea to the lens. The cornea provides much of the eye’s focusing power. back

Fovea
The fovea is the center area of the retina that receives the focus of an object. Nerve cells are more densely packed in this area, which allows the fovea to focus images in greater detail. back

Iris
The iris is the colored part of the eye. Tiny muscles inside the iris dilate (widen) and contract (narrow) the size of the pupil, much like an aperture on a camera. back

Lens
The lens focuses light onto the retina in the back of the eye. back

Macula
The macula is the small and highly sensitive part of the retina responsible for detailed central vision. The macula allows us to appreciate detail and perform tasks that require central vision, such as reading. back

Optic Nerve
The optic nerve transmits electrical light impulses from the retina to the brain for processing. back

Pupil
The pupil is the black, circular opening in the center of the iris. It regulates the amount of light entering the eye. back

Retina
The retina is a very thin layer of light-sensitive tissues that line the inner part of the eye. It is responsible for capturing the light rays that enter the eye, converting them to light impulses and sending them to the brain for processing. back

Retinal Pigmented Epithelium
A layer of pigmented cells that nourishes and supports the retina. back

Sclera
The sclera is the tough, opaque tissue that serves as the eye’s protective outer layer. It is also known as the "white of the eye." back

Trabecular Meshwork/Canal of Schlemm
The passageway in the eye for aqueous fluid to leave the eye. back

Vitreous
The vitreous is a thick, transparent and colorless substance that fills the center of the eye behind the lens. It is composed mainly of water, comprises most of the eye’s volume and gives the eye its form and shape. back

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