The best possible vision is achieved by setting your eyes to see clearly in the distance with a standard IOL, and to wear glasses for near work. However, some people who don’t want to wear glasses elect to have mono-vision.nOne eye is set to see well in the distance and the other eye is set to see clearly at near. This allows clear distance vision with one eye and near vision with the other. However, not everyone can tolerate a difference between the eyes. Therefore, a trial of mono-vision with contact lenses is required prior to undertaking surgery.