Lens and Ciliary Body

What are they?

The lens is a completely clear, fairly flat sphere inside your eye used to focus light to a point, called the macula (where your center of vision is), in the back of your eye. It is enclosed in a thin bag, with connective ligaments that attach it to a muscle structure called the ciliary body.

The ciliary body can pull the lens or fatten it, as well as produces aqueous humor (liquid that makes the cornea bulge). Damage to the lens is irreversible and cannot be repaired, but only replaced by an implant lens. Over time, especially in old people, old cells of the bag encasing the lens will die and accumulate on the lens, causing cataracts.

What do they do?

We control the lens to see near and far objects by changing the size of the lens. The ciliary body is a muscle structure around the lens that constrict to pull on the ligaments and fatten the lens so we can see close up. It also can pull away from the lens, causing the lens to flatten out to allow us to view distant objects.

When a baby is born, the lens is almost all round. They have to learn to focus light just like they have to learn to talk. This means that babies are not born with clear vision.

All of us have looked into a spoon and saw ourselves upside-down. The lens does the same thing to images that pass through it. In fact, all images are upside down until it gets to the brain. The brain just flips it the other way around.