What is my refractive error?
Myopia
or commonly nearsightedness
is the inability to see distant objects well. Hyperopia
or in common terms farsightedness
is the difficulty to see close objects clearly. If near vision difficulty
occurs in a normal-sighted person over 40 years, then it is called
presbyopia. Sometimes
both close and distant objects are seen blurred or ghosted. This might
be caused by astigmatism
(very severe myopia or hyperopia may cause blurred vision for both
distances). If you can not decide, the easiest way is to look at your
prescription.
At your prescription, you will notice 2 main columns:
One titled with OD or R (RE) which means your right eye and the other
OS or L (LE) which means your left eye. Under this OD or R title you
will see 3 sub-titles (or columns) which are labelled as Sph. (spherical),
Cyl (cylindrical) and Axis. Sph values show the magnitude of the lens
you need to put on in order to compansate for your hyperopia or myopia.
By the way, the unit of the lens magnitude or power is diopter (D).
It shows the focusing power of the lens: 1 D means the lens focuses
at 1 meter, 2 D means ½ meters, 4 D means ¼ meters. If there is +
sign before that value, it means that you are hyperopic, if it is
a - value, then you are a myopic person. If you are over 40, there
may be three lines under the sph column, and at one line you might
be myopic but at the others you might be hyperopic. Due to aging,
the eye can not accommodate for close distance (presbyopia). This
extra line is for "near / add" or "reading glasses".
The other columns Cyl and Axis describes the lens you need to neutralise
your astigmatism. Cyl shows the magnitude and axis is the orientation
of the cylindrical lens in degrees.
Still confused? Fax-us your prescription or fill out our info-request
form, we will be happy to inform you about your refraction error
or eye problem.
