It is one of the main reasons for having blurred vision which many people are not aware of. It is stated to be one of the common reasons for having eyesight problems. This condition brings nearsightedness or farsightedness along with it.
It is caused mainly due to irregular shape of the cornea or of the lens which is located behind the cornea and is called as lenticular astigmatism. The problem can be corrected by use of eyeglasses, contact lenses or refractive surgery.
To put it in lay man