On your prescription, you’ll see some letters followed by a series of numbers. The letters “OD” indicate that the prescription is for your right eye; “OS” represents your left eye. Your prescription, including both eyes, will generally look something like this:
OD – 4.00 -1.50 x 180
The first number in the series identifies your degree of nearsightedness (myopia) or farsightedness (hyperopia). A plus sign (+) indicates you are farsighted, a minus sign (-) indicates you are nearsighted. This number is called your spherical correction.
The second number in your prescription identifies what degree of astigmatism you have i.e. how well or poorly your eye focuses light onto the retina. The number can be written either with a (+ sign) or a (- sign). This number is called your cylindrical correction.
The third number indicates the direction of your astigmatism. For example, an axis of 180 degrees means the astigmatism is horizontal. If your prescription doesn’t have a second or third number, you most likely don’t have astigmatism.
An additional number may be present that indicates an add power that will assist
DV Your prescription might also contain the abbreviations DV (distance vision). DV is the portion of your prescription which corrects your ability to see things far away.
NV means your prescription is for reading only.
Your prescription may only require part time wear for distance or near activities, especially small print.