Anatomy of the eye

Anatomy of the eye

An eye consists of several parts that work together to ensure good vision.

Eyelids: Eyelids protect our eyes from drying out, dirt, and bright light. We blink about 20,000 times a day. Blinking keeps our eyes moist, which prevents them from drying out. We blink, just like squinting is a reflex.

Sclera: The sclera provides the eye with strength. The sclera is the outermost layer of the eye and transitions into the cornea.

Cornea: The cornea is the transparent part at the front of the eye. Light enters our eye through the cornea. The cornea functions as a kind of lens. The cornea does not contain blood vessels, so there is no supply of oxygen and nutrients. Because the cornea does need oxygen, it gets it from the outside air. That is why it is important for people with contact lenses that the lenses allow sufficient oxygen to pass through.

Iris: The iris ensures that the right amount of light enters the eye. The iris is a sphincter muscle that can enlarge the pupil (in low light) or reduce it (in high light). In addition, the iris (also called the iris) determines the color of the eye.

Pupil: The pupil is the opening in the iris where light enters. When there is a lot of (bright) light, the pupil becomes smaller. When there is less light, the pupil enlarges.

Eye lens: Behind the pupil is the eye lens. The eye lens and the cornea work together to project incoming light rays onto the retina. This is necessary for sharp vision. In order to see well both near and far, the lens adjusts its curvature.

Anterior and posterior chambers: The chambers are located between the cornea and the iris (anterior chamber) and behind the iris near the lens (posterior chamber). Both chambers are filled with aqueous humor. The aqueous humor provides oxygen and nutrients.

Vitreous: Behind the lens of the eye is a cavity filled with vitreous. Vitreous ensures that the eye maintains its round shape. This is important for the correct refraction of light (and therefore for good vision).

Retina: The retina ensures that the projected images are converted into electrical signals. These signals are sent to the brain via the optic nerve.

Choroid: The choroid lies between the retina and the white of the eye. This membrane consists of small blood vessels that supply the eye with nutrition. The choroid continues into the iris.

The yellow spot: The yellow spot (macula) is located on the retina and ensures that we can see fine details. How well we can do this is expressed in visual acuity.

Optic nerve: The optic nerve (a collection of nerve fibers) is located at the back of the eyeball. The nerve fibers transmit a signal that is transmitted to the brain via the optic nerve pathway.

Tear gland: The tear glands are located on the outside above the eye. Tear glands produce tear fluid. This fluid is spread over the eye when we blink. This protects our eyes from drying out.