If you really need eyesight correction following an eye exam, the optometrist or ophthalmologist will tell you if you are farsighted or nearsighted. They also explain how you can get rid of astigmatism.

With any medical diagnosis, you will be provided a prescription for a remedial eyeglass. You will see a prescription may have some abbreviated terms, for example:


Do you know what these terms are? We described below.

OD vs OS

The first thing about comprehending the prescription from the optometrist is understanding OS and OD. These are actually abbreviations for Latin words:

OS or “oculus sinister,” is for “left eye.”
OD or “oculus dexter,” is for “right eye.”

The prescription may also have a field for OU, which means “oculus uterque,” for both eyes.

Despite the fact that Oculus Sinister and Oculus Dexter are conventional abbreviations used in prescriptions for glasses, eye medicines, and contact lenses, there are many eyes professional who’ve improved their prescription by changing OS with LE (left eye) and OD with RE (right eye).

If you are going to buy prescription glasses online, then buying it from Firmoo.com is actually quite easy. Choosing the frame that you like and ordering the lenses according to the prescription from your eye doctor both occur hand in hand. When you buy your eyeglasses from firmoo, you’d have the chance to select from a variety of frames in different colors, styles, and designs. You’d have the vintage frames as well as the cooler and newer frames.

Other Terms on Eyeglass Prescription

Other terms you might see on the eyeglass prescription include CYL, SPH, Prism, Add, and Axis. So, let us know what all these terms are.


SPH means “sphere,” which signifies the strength of the particular lens your eye doctor is recommending to fix your eyesight.

If you have myopia (nearsightedness), the number may have a minus sign. If you have hyperopia (farsighted), the number may have a plus sign.


CYL means “cylinder,” which signifies your lens power an eye doctor prescribed to cure your astigmatism. In case there is no number in this particular column, then the doctor could not find astigmatism or astigmatism doesn’t have to be remedied.


Axis is usually a figure from 1-180. In case your doctor has incorporated cylinder strength, there’ll also be an axis number to show placement. Axis is actually evaluated in some levels and represents exactly where the astigmatism is positioned on your cornea.


Add is usually used for multifocal lenses to point the extra magnification for the lower part of the lens.


Prism exclusively is found on a lower number of prescriptions. It is actually used when the doctor has the opinion that adjustment of eye positioning is important.

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Notes on The Eyeglass Prescription

When reviewing the eyeglass prescription, you might see particular lens suggestions that the doctor has incorporated. These are generally recommended and may have extra charges:

Progressive lenses: These types of lenses are multifocal lenses with zero lines.

Anti-reflective coating: Also known as anti-glare coating, this particular coating cuts down glare, which means that more light can pass through the lenses.

Photochromic lenses: Generally known as light-adaptive lenses and variable tint lenses, this will make the lenses darken while exposed to natural light.

Don’t Confuse Contact Lens Prescription with Eyeglasses Prescription

Although the eyeglass prescription has all the details important for you to purchase eyeglasses, it does not have details required for buying contact lenses.

These details consist of:

lens brand name and manufacturer
lens size in diameter
the contour of the surface of the lens

Your eye doctor may also change the amount of remedial power between eyeglasses and contact lenses depending on the distance your lens will be from your eye. Eyeglasses have to do with twelve mm (millimeters) away from the surface area of your eye while contacts are specifically on the surface area of your eye.

According to your particular condition – currently wearing corrective eyeglasses, risk factors, and age, – the majority of eye doctors recommend having a detailed eye check-up every year.