Monofocal Intraocular Lenses (IOLs) are the traditional lenses used for cataract surgery. This type of lens is very effective at restoring functional distance vision. They have one point of focus. While distance vision is improved, most patients still need to wear glasses for other distances, like reading and computer work. Monofocal IOLs don’t correct astigmatism, so people who have astigmatism may still need to wear distance glasses.