Most people over the age of about 45 who wear glasses for distance gradually find it more difficult to focus on near objects. Reading becomes more difficult and they also require reading glasses. These are great for reading, but make everything in the distance blurred. One solution is to wear bifocal lenses. The top of the lens allows you to see in the distance while the bottom of the lens gives you clear near vision. This gives you clear distance and near vision in one pair of glasses.