Your Glasses Prescription Explained

Deciphering the jargon detailed on your latest prescription is a dilemma that many glasses wearers face. In fact for the majority of individuals who wear glasses and undergo regular eye tests finding lenses that satisfy your prescription would be impossible without the help of your optician.

Understanding the numbers and abbreviations on your prescription is more than just sourcing the right lenses to correct your vision, it can also help you gauge the condition of your eyes and how your sight has improved or deteriorated since your last test. As an Essilor Varilux Consultant Optician, Lenses in Glasses understand the importance of fitting your new prescription with your new eyewear, and here we explain just what the words and numbers on your latest prescription actually mean…

SPH

Sphere, abbreviated as SPH on your prescription, relates to whether you are long or short sighted and just what power is required to correct your vision. A plus (+) means that you are long sighted, whilst a minus (-) means that you are short sighted and can only see things up close without glasses. The number next to this symbol relates to the strength of the lenses needed, the higher the number, the stronger the lenses required.

CYL

CYL stands for cylinder and records the level of visual distortion or astigmatism you are experiencing as a result of the shape of your cornea. A low number means that your eyes are almost round, whilst a high number means that your eyes are oval in shape. This box may be blank if your eyes are perfectly round.

The AXIS reading will also indicate the direction of your astigmatism so lenses can be positioned correctly.

PRISM

If your eyes do not work well together then the level of imbalance will be recorded here. The BASE reading works with this to indicate whether a prism is required to correct this imbalance.