Lt Col Reynolds
The lens, which is located behind the iris, works together with the cornea to refract light rays. It’s also responsible for changing the focal distance of the eye to create clear images of objects at various distances. Dr. Flemings, can you tell us more about the lens?

Lt Col Flemings
Of course, Dr. Reynolds. The lens is in the shape of an ellipsoid, or a stretched-out sphere, like an olive. It’s also biconvex, meaning it’s rounded outward on both sides. The shape and size of the lens varies as it changes its focus.

The lens consists of the lens capsule, the lens epithelium, and the lens fibers. The lens capsule is a smooth, transparent membrane composed of collagen that completely surrounds the lens. The capsule is extremely elastic.

The lens epithelium makes up the next layer. The cells of the lens epithelium continuously create new lens fibers for the lifelong growth of the lens. The lens epithelium is also responsible for maintaining stable function of the lens.

Finally, the bulk of the lens is made up of lens fibers. These are long, thin, transparent cells that are layered like an onion. As the lens epithelium generates new lens fibers, they are added to the outermost layer, called the cortex. The oldest layers, located at the core of the lens, form the nucleus.