How to read eyeglass prescriptions from your doctor and optician

When you feel a disturbance in your vision, such as a slightly blurry vision or you are unable to see over long distances, this could be a sign that you may need glasses. So, before buying glasses, of course, you need to undergo an examination and get an eyeglass prescription from a doctor. However, do you understand how to read an eyeglass prescription?

The easy way to read eyeglass prescriptions

Symptoms such as blurry eyes and not being able to see far can indicate that your eye health has deteriorated. Vision problems like this make you need glasses.

Before buying glasses, your eyes will be checked so that the glasses you use match the needs of your eyes. You can get your eyes checked by a doctor and you will also get an eyeglass prescription from the doctor.

There are various disorders of vision, such as nearsightedness, farsightedness, cylindrical eyes, and so on. This eye disorder also has strengths, such as -1, +2, -2.5, and others. From an eyeglass prescription, you can find out the strength of your eye irritation.

However, the problem lies in how to read the eyeglass prescription because of the many abbreviations and numbers in the prescription table. For that, you should pay attention to which recipe for right eye and left eye first.

In the leftmost column and row, it will usually say OD and OS or R and L. Here's how to read the abbreviations on your eyeglass prescription:

• OD (Oculus Dextra): is the Latin term for the right eye. This is the same as R, which stands for Right (right in English).
• OS (Oculus Sinistra): which is the Latin term for the left eye. This is the same as L for Left (left). Sometimes, you may also find the inscription OU, which stands for Oculus Uterque and means both eyes.

After you know which recipe for the right and left eye, then you can move on to the next table column. There, you will find the words SPH, CYL, AXIS, ADD, and PRISM. What do these abbreviations mean?

1. SPH

SPH on an eyeglass prescription stands for sphere. It shows the amount of lens power required by your eye, it can be a plus lens or a minus lens.

If the number written in that column has a minus sign (-), it means that you are nearsighted. If the number written in the column is followed by a plus sign (+), it means you are nearsighted.

The bigger the number you write (regardless of the minus or plus sign), the thicker the lens your eye will need.

2. CYL

CYL stands for cylinder. On an eyeglass prescription from a doctor, CYL shows whether you have a cylinder eye or not, along with the amount of lens power for the cylinder.

If no numbers are written in this column, it means you don't have cylinder eyes or you have very few cylinders so you don't need to wear glasses with cylindrical lenses. If the number in this column is written followed by a minus sign (-), it means the lens power for nearsighted cylinders. And, if the number is followed by a plus sign (+) it means for farsighted cylinders.

3. AXIS

AXIS is the orientation of the cylinder, which is shown from 0 to 180 degrees. If your eye is cylindrical, the AXIS value should also be written according to the cylinder power.

Usually, the AXIS value is written preceded by "x". Example: x120, meaning that the angle of the cylinder lens is 120 degrees to correct the cylinder eye.

4. ADD

In an eyeglass prescription, ADD means a magnifying force added to the bottom of a multifocal lens to correct presbyopia (myopia) or for reading needs.

Numbers written in this column are always in plus strength (although they may not be marked with a plus sign). Generally, this number ranges from +0.75 to +3, and is usually the same strength for each eye.

5. PRISM

This indicates the amount of correction some people may need to align the eyes so that vision looks straight.

If any, the number of prisms will be written as a fraction or decimal followed by the direction of the prism. There are four abbreviations for the prism direction, namely BU (base up = above), BD (base down= down), BI (base in= towards the user's nose), and BO (base out= towards the user's ear).

Can an eyeglass prescription be used for contact lenses?

After knowing how to read an eyeglass prescription from a doctor, you may wonder whether it is okay to use the prescription for wearing contact lenses. Sometimes, there are some people who also need contact lenses because they are more practical and can support their daily activities.

However, it is important to remember that most eyeglass prescriptions are not the same as contact lens prescriptions. According to information from the GP Contact Lenses site, this is because the positions of the glasses and contact lenses are quite different. Given this distance, the size of the lens strength listed on the prescription table will be different.