Interpreting your optician’s prescription is fairly straightforward once you know some of the terms used. It will be written in the format below and providing your optician’s prescription has not expired then it can be used to order your glasses.
Distance Prescriptions
This is a typical prescription for someone who is “Short sighted”;
| | Sphere | Cylinder | Axis | Prism | Base |
| Right Eye | -3.25 | -1.75 | 5 | | |
| Left Eye | -3.25 | -0.75 | 175 | | |
And this is an example of a prescription for someone who is “Long sighted”;
| | Sphere | Cylinder | Axis | Prism | Base |
| Right Eye | +3.00 | +1.25 | 175 | | |
| Left Eye | +2.50 | +0.75 | 75 | | |
| | Sphere |
| Reading Addition | +2.00 |
| Intermediate Addition | +1.25 |
If you have an optician’s prescription for distance it may be written or printed as illustrated above. So what does it mean?
Sphere (or Sph)
Sphere or spherical. The minus (-) sign or plus (+) signs indicates whether you’re short sighted (-) or long sighted (+) and the number indicates the degree of correction that’s required, the larger the number the more short or long sighted you are.
Cylinder (or Cyl)
Cylinder this part of the prescription is required if you have astigmatism, you may recall being told that your eyes are rugby ball shaped as apposed to a football. Amounts of astigmatism up to 3.00 are not uncommon. The minus (-) or plus (+) signs are very important to us as they indicate how we must make your lenses.
Axis.
The Axis is the direction that the Cylinder must be positioned in front of your eye to give you optimum vision. The Axis will be a number between 5 and 180 usually in 5° steps. Occasionally you will see steps of 2.5° or even steps of 1°.
Please note that if the Cylinder and Axis boxes are empty then you don’t have astigmatism at this stage in your life.
When entering the details in the Your Prescription section please ensure that the numbers are accurately entered into their corresponding boxes. Please take care that the correct signs are used, minus (-) or plus (+).
The Reading Addition is used to configure your glasses for reading comfortably. The Intermediate Addition is to allow for mid range use such as Computer Display etc. These applications can be selected as you configure your glasses during the order process on our website.
Your Pupilary Distance (PD) is the distance between the centres (pupils) of each of your eyes, measured in millimetres. Your PD measurement is used when we take a lens with your prescription and customise it to both fit your frame and you. To be effective, a lens must be cut so the centre is directly in front of your pupil. Without your PD it is difficult to work out where that point is for you. Your PD can be provided in minutes by your optician or doctor, and so we highly recommend that you ask for it when you have your eyes tested. Alternatively, you may also choose to use an average PD, which is provided for you as a default when ordering.