There are three main types of refractive errors:
1) Myopia (nearsightedness): This occurs when the eyeball is too long or the cornea is too curved, causing light to focus in front of the retina instead of on it. This results in difficulty seeing objects far away.
2) Hyperopia (farsightedness): This occurs when the eyeball is too short or the cornea is too flat, causing light to focus behind the retina instead of on it. This results in difficulty seeing objects up close.
3) Astigmatism: This occurs when the cornea or lens is not perfectly round, causing light to focus in more than one spot on the retina. This can result in blurred vision at all distances.
Refractive errors are usually diagnosed during a comprehensive eye exam. The eye doctor will use a variety of tests to measure the shape of the eye, the curvature of the cornea, and the distance between the pupil and the retina.
Refractive errors can be corrected with glasses, contact lenses, or refractive surgery.
Glasses work by changing the way light enters the eye. Convex lenses are used to correct nearsightedness, while concave lenses are used to correct farsightedness. Cylindrical lenses are used to correct astigmatism.
Contact lenses work in the same way as glasses, but they are placed directly on the eye. This can provide better vision correction than glasses, and it can also be more comfortable for some people.
Refractive surgery is a permanent solution for refractive errors. It involves reshaping the cornea using a laser to improve the way light focuses on the retina. Refractive surgery can be effective for nearsightedness, farsightedness, and astigmatism.
The type of refractive error correction that is best for you will depend on your individual needs and preferences. Talk to your eye doctor about the different options available to you.
