Your Prescription Explained

At the end of your eye test we'll give you a glasses prescription if you need one. Here's what it means. (Contact lenses require a separate assessment and a special prescription.)

R and L

‘R’ refers to your right eye, ‘L’ to your left.

SPH (sphere)

The amount of power required to correct your vision.
Plus (+) lenses are used to correct long sight.
Minus (-) lenses to correct short sight. The higher the number, the stronger the lens required.

CYL (cylinder)

Amount of correction (if required) to remove any visual distortion, caused by an irregularly shaped cornea known as an astigmatism.


The direction that the cylinder (if required) will be built into your lenses to correct your astigmatism. It is measured in degrees between 0 and 180


Any correction (if required) to help balance your eye muscles so they work as a pair more comfortably.


The direction that the prism (if required) will be built into your lenses.

ADD Inter

The amount of correction that needs to be added to your prescription to enable you to cope with intermediate distances, such as working at a computer or reading music.

ADD Near

This is the amount of correction that must be added to your distance prescription to enable you to see near objects clearly, such as reading a book or map.

Special Offers
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£10 eye check
Plus get 10% off glasses

Customer Comments:

The best eye test I ever had, excellent. When it came to choosing frames they were very honest, helpful and let me make my own decision. I was very pleased with the all round service.
S. Ince, Mansfield

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