Have you ever tried to read the prescription your eye doctor or certified Titan Eye Plus optometrist has given you? The one with all the numbers and letters, not to mention the plus and minus signs? Things can get a bit confusing if you don’t know what you’re looking at. Apart from gaining the know-how, being able to read your prescription will help you order the right pair of eyeglasses.

Reading The Grid

Our eyes function independently of each other. It’s our brain that combines the two perceptions into a single, three-dimensional vision. As such, they can have different responses to our environment and lifestyle stresses. This is why they are tested separately with each eye having its own values. To begin with, you need to know what each eye stands for on that piece of paper. OD, OS and OU are used to identify your eyes. OD, short for oculus dexter from Latin is used for your right eye and OS, oculus sinister, refers to your left. When referring to both eyes, OU or oculus uterque is used.

Usually, you’ll find five column headings in an eye prescription; Spherical, Cylinder, Axis, Prism and Base. The column under Spherical denotes the lens power required in each eye. That’s the most basic kind of correction your vision needs. A higher number in this column indicates a higher lens power and needs more correction. There’s a plus or minus sign before each of these numbers that will show you whether you are near-sighted (poor distance vision) or far-sighted (poor near vision), respectively. A “plus” (+) sign in front of the number means you are far-sighted, and a “minus” (-) sign means you are near-sighted. 

An irregular curvature of the cornea, is measured under the Cylinder column. The bigger the number under this, the more your vision is distorted. The Axis values directly correlate with those under Cylinder. They help determine how your lenses will be positioned.

While we understand that all this information can overwhelm you, we recommend that you visit our stores and have our team take you through the process.

The Technical Details

The next set of numbers guide your optometrist in customising your lenses so that you can enjoy clear, undistorted vision. Eyeglass lenses are designed to direct your vision through an ideal spot on them. So, the optometrist at your Titan Eye Plus store will need to know if you have any alignment problems that need to be compensated for. Prism values are usually used to correct double vision resulting from muscle imbalance in the eyes like a squint for example. These misalignment values appear under the Prism column; while the Base value is used to indicate where thickest edge of the prism is, to correct any misalignments.

When a person reaches the age of 40, it’s natural to have difficulty in reading and that’s when ADD column comes in to play. Additionally, any number under the ADD column is used for the magnifying power that will help you read. It will always have a plus sign before it and is only added to multifocal lenses. Generally, the value will be the same for both your eyes.

All prescriptions will have the measurement of Pupillary Distance (PD), that is the distance between the centre of the right eye’s pupil to the centre of the pupil of the left eye. These centres help to position the lenses at the appropriate spot to ensure proper vision and visual comfort.

If you still have any questions regarding your eyeglass prescription, reach out to the qualified optometrists at Titan Eye Plus stores who can help you decipher these terms and numbers, and guide you while ordering eyeglasses.