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 colourful with a cataract. Cataract surgery removes this cloudy lens and replaces it with a clear IOL to improve your vision.