Myopia, hyperopia, astigmatism, presbyopia … the eye is a complex and fragile organ that can present defects. An eye that’s too long or too short, irregular curvature of the cornea, the slightest flexibility in the crystalline lens… every visual defect has a physiological explanation but also an appropriate corrective lens. These may be divergent or concave lenses for myopia, convergent or convex lenses for hyperopia, toric for astigmatism, near vision or progressive lens for presbyopia.
This widespread visual defect is characterized by a difficulty to see things far away. Today, myopia affects a growing number of people worldwide, particularly in Asia and among younger people. Lack of outdoor activities and intensive screen use may accentuate it.
Someone with hyperopia can see well close-up and at a distance, but has to make a constant effort to do so, which can provoke headache.
Someone who is astigmatic has imprecise near and far vision. In particular, in peripheral vision images can sometimes appear deformed. Astigmatism may be combined with other eyesight problems such as hyperopia, myopia.
Presbyopia is not a visual defect but a natural evolution of our vision. No one is born with presbyopia but we all develop it. It affects both women and men from the early 40's onwards.