Prescription Guide



Everything you need to know to understand and send your prescription.

Sometimes prescriptions can be confusing, so we?ll explain the most common formats.

Your prescription might look like these examples:

Here?s what prescription terms mean:

RE or OD Right eye (R)
LE or OS Left eye (L)
SPH Spherical power (you will find numbers like -0.50,-0.75, 1.50, +1.50, etc)
CYL Cylindrical power (you will find numbers like -0.50,-0.75, 1.50, +1.50, etc)
AXIS It is axis of cylindrical power (you will find numbers between 1 to 180
PD Pupillary Distance, It is the distance between the left and right pupil. (usually it ranges between 48mm to 73mm for adults and 41mm to 55mm for children for both eyes. )
D.V Distance Vision
N.V Near Vision

Sphere (SPH):This indicates the amount of lens power, measured in diopters (D), prescribed to correct the refractive errors

Cylinder (CYL):This indicates the amount of lens power for astigmatism. If nothing appears in this column, you have no astigmatism.


Axis:The axis is defined with a number from 1 to 180.
If an eyeglass prescription includes cylinder power, it must include an axis value, which follows the cyl power.

Add: This is the added power applied to the bottom part of progressive or bifocal lenses to correct presbyopia. The number appearing in this section of the prescription is always a "plus" power, even if it is not preceded by a plus sign. Generally, it will range from +0.75 to +4.00 D.