Understanding your prescription
Your prescription can be written in different ways. Here is a short explanation as to how to interpret your prescription.
The Right and Left
The right eye may be written as right, R, RE or OD. The left eye may be written as left, L, LE or OS.
Sphere (SPH)
The Sphere power is the first number in the prescription. It is usually a + (plus) or - (minus) number, but can be 0.00 (or plano, pl, or just left blank).
Cylinder (CYL)
The Cylinder power is the second number in the prescription. It is not included in every prescription. If included, it is usually a - (minus) number.
Cylinder Axis (Axis)
The Cylinder Axis is the third part of the prescription. If there is a cyl included in your prescription, the cyl power will be followed by an ‘x’ then a number.
Add
Add is the additional power, added on to the sphere power, to give the reading prescription for those who need it.