Right / Left

The prescription for your right and left eye are usually labeled by an R / Right / OD for the right side and L / Left / OS for the left side.

Sphere

The sphere for correcting nearsighted and farsighted vision is most often labeled with S or SPH. It is usually in 0.25 increments. Pay attention to plus or minus! If neither plus (+) or (-) is explicitly written, it is a plus value.

Cylinder

The cylinder together with the axis corrects astigmatism. It is usually labeled with a Cyl and written in 0.25 increments. Not every prescription has a astigmatism correction. If the CYL column/row on your prescription is empty (or has a sph written in it), you don't have a astigmatism correction and can enter 0.00 in our order form.

Axis

The axis is together with CYL part of astigmatism corrections. It is written in 1 increments in a range of 0 to 180. It is only part of your prescription if you have a CYL too.