The eye’s natural lens, located inside the eye (beneath the cornea, the iris and the pupil), is responsible for focusing close up, so we can read and focus on nearby objects. The natural lens is surrounded by a muscle that squeezes it to make it more convex; this increases the eye’s refractive power so we can read fine print, for instance. As we reach our 40s and 50s, this mechanism will gradually stop functioning, and we will note a progressive inability to focus on nearby objects. The condition is referred to as presbyopia. For those who have distance vision that is still good, reading glasses will now be required. For those who also have difficulty focusing in the distance, progressive, bifocal or trifocal lenses may be needed. Laser vision correction can be used to reduce the inability to focus close up, turning back the clock to restore adequate reading vision.
