We use corrective lenses to improve vision in cases of refractive problems.
Once the refractive error has been assessed and measured, a prescription is required to manufacture the corrective lenses. Below you can see what the numbers in your easee prescription mean.
The terms OD and OS specify which eye the correction is meant for. OD, from Latin Oculus Dexter, means right eye while OS, Oculus Sinister is Latin for left eye.
The term Sphere (S) refers to the lens’s spherical power, which is measured in dioptres (dpt) and is equal in all meridians. This is used to correct nearsightedness (myopia) or farsightedness (hyperopia). If the sign appearing before the number is minus (-), you are nearsighted. If it is plus (+), or has no sign at all, you are farsighted.
Cylinder (Cyl) indicates the lens power required to correct astigmatism. The cylinder value always follows the sphere value in your prescription. If you do not have astigmatism or you have a very slight astigmatism, your prescription will not include a cylinder value. Cylinder can be documented with a minus or plus sign. At easee we use the minus sign.
The Axis (AX) always follows the cylinder in a prescription. The axis is documented in degrees and refers to the direction that the cylinder power is located to correct the astigmatism.