If you have an eyeglasses prescription, you may notice there are OS, OD and other abbreviations on the prescription chart. So, what do they mean? This post will give you a full explanation.
What Are OD and OS?
The abbreviation OD is frequently used in eye care and has two distinct meanings and it is the abbreviation for the Latin term Ocular Dexter, which means right eye. When OD is written next to your eye doctor’s name, it is the professional abbreviation for Doctor of Optometry. At the same time, OS is the abbreviation for Ocular Sinister and is Latin for the left eye.
Sometimes, you may see OU in your prescription, which is an abbreviation for Oculus uterque, Latin for both eyes.
Although OS and OD are traditional abbreviations used in the prescription for eyeglasses, contact lenses, and eye medicines, there are some doctors who have modernized their prescription forms by replacing OD with RE and OS with LE.
Other Abbreviations on Eyeglasses Prescription
SPH, an abbreviation of the sphere, which indicates the power of the lens your doctor is prescribing to correct your vision. If you are myopia, there will be a minus sign before the number. If you are hyperopia, there will be a plus sign before the number.
CYL, an abbreviation of the cylinder, which indicated the lens power your doctor is prescribing to correct astigmatism. If there is no number in this column, then your doctor has not found astigmatism or your astigmatism does not need to be corrected.
Axis is a number from 1 to 180. If your doctor has included cylinder power, there will also be an axis value to indicate positioning. Axis is measured in degrees and refers to where the astigmatism is located on the cornea.
Add is used in multifocal lenses to indicate the additional magnifying power for the bottom part of the lens.
Prism only appears when the prescription is too low. It is used when your doctor feels that compensation for eye alignment is necessary.
To sum up, this post from Koalaeye Optical has shown what OS and OD are. If you have any different ideas for OS vs OD, share them in the comment zone. If you have any problems with glasses, please feel free to contact us via the email firstname.lastname@example.org and we will reply to you as soon as possible.