In cataract surgery, the natural lens has to be removed from the eye. In most cases a permanent intraocular lens (IOL) is implanted for replacing the natural lens in order to restore the focusing power. Traditional IOLs are monofocal, i.e. offer vision at one distance only (near, far or intermediate). But traditional IOLs mean that you must wear eyeglasses or contact lenses for reading for viewing objects etc. The new multifocal intraocular lens (IOL) offer the possibility of viewing at more than one distance, without using eyeglasses or contacts.