If Your Eyes Have Astigmatism, You Read

Astigmatism is a common eye condition that’s usually corrected by eyeglasses, contact lenses, or surgery.
Astigmatism is caused by an eye that is not completely round and occurs in nearly everybody to some degree. For vision problems due to astigmatism, glasses, contact lenses, and even vision correction procedures are all possible treatment options.
A person’s eye is naturally shaped like a sphere. Under normal circumstances, when light enters the eye, it refracts, or bends evenly, creating a clear view of the object. However, the eye of a person with astigmatism is shaped more like a football or the back of a spoon. For this person, when light enters the eye it is refracted more in one direction than the other, allowing only part of the object to be in focus at one time. Objects at any distance can appear blurry and wavy.
Astigmatism is a natural and commonly occurring cause of blurred vision that is usually associated with an imperfectly shaped cornea. The exact cause in not known.

Types of Astigmatism

There are three primary types of astigmatism:

Regular or Irregular Astigmatism

Astigmatism also is classified as regular or irregular. In regular astigmatism, the principal meridians are 90 degrees apart (perpendicular to each other). In irregular astigmatism, the principal meridians are not perpendicular. Most astigmatism is regular corneal astigmatism, which gives the front surface of the eye a football shape.

Eye Test for Astigmatism

Place yourself at approximately 1m from the screen.
Cover one eye with your hand, without pressing on the lid, and take the test. Cover the other eye and begin the test again.

If some of the lines appear grayer and some blacker, you probably have an astigmatism – consult your eye care specialist.

Reference

http://www.webmd.com/eye-health/astigmatism-eyes

http://www.allaboutvision.com/conditions/astigmatism.htm

http://www.essilor.com/en/EyeHealth/LensesForYourVision/TestyourEyes/Pages/EyetestforAstigmatism.aspx

http://www.aoa.org/patients-and-public/eye-and-vision-problems/glossary-of-eye-and-vision-conditions/astigmatism?sso=y