Understanding an Eyeglass Prescription:
OD is the right eye
OS is the left eye
There are 3 parts to an Eyeglass RX
Spherical or SPH
Cylinder or CYL
If the patient has Astigmatism, their RX will contain CYL & AXIS
If the patient does not have Astigmatism, there are only numbers following the Spherical or SPH areas on the RX Sheet.
Eyewear Prescriptions are measured in diopters.
Eyewear Prescriptions are either +Plus Powers or -Minus Powers.
-1.00 is read: Minus 1 Diopter
+0.50 is read: Plus half Diopter
Attached is an image to help understand every area of a written prescription