An intraocular lens (or IOL) is a tiny, artificial lens for the eye. It replaces the eye’s natural lens that is removed during cataract surgery.
The lens bends (refracts) light rays that enter the eye, helping you to see. Your lens should be clear. But if you have a cataract, your lens has become cloudy. Things look blurry, hazy or less colorful with a cataract. Cataract surgery removes this cloudy lens and replaces it with a clear IOL to improve your vision.
Most IOLs are made of silicone or acrylic and come in different focusing powers similar to prescription glasses or contact lenses. They are also coated with a special material to help protect your eyes from the sun’s harmful ultraviolet rays.
There are two types of IOLs, one is monofocal and the other is multifocal. The monofocal lens is a fixed distance and multifocal IOLs provide both distance and near focus at the same time. The lens has different zones set at different powers. It is designed so that your brain learns to select the right focus automatically.