Your prescription is split into three sections, Sphere, Cylinder and Axis. You will most commonly see this written as, Sph, Cyl and Axis.
Sphere: Is always a number in 0.25 jumps (i.e. 0.25, 0.50, 0.75, 1.00, 1.25). This can either be written in minus or plus (- or +).
IMPORTANT: You must select the correct symbol when ordering (minus or plus, - or +) as selecting the wrong sign will create the completely wrong prescription required to correct your vision.
Cyl - Is always a number in 0.25 jumps (i.e. 0.25, 0.50, 0.75, 1.00, 1.25). This can either be written in minus or plus.
IMPORTANT: You must select the correct symbol when ordering (minus or plus, - or +) as selecting the wrong sign will create the completely wrong prescription required to correct your vision.
Axis - Is a number between 0 and 180, it can also be written to point five (0.5) of a degree. This simply happens if the optometrist can't decide wether you prefer for example 79 or 80 so they simply write your axis as 79.5. In this case lets get your glasses as accurate as possible so please provide us with the 79.5. If there is no axis please leave it blank.
The instances when a prescription doesn't have a value for the Cyl section please leave the Axis blank (or some opticians write this as 0.00), the Axis is indicating what degree the Cyl figure sits at so if there is no Cyl there is no Axis required.
Add - This is a value which is added to your distance vision to create your reading (near) vision prescription. If purchasing single vision eyewear we do not require this figure. If purchasing varifocals you will need to enter the Add value as well as your distance prescription.
Prism - If you have Prism in your prescription we ask that you place an order leaving the prism out and leave a note in the checkout comments box stating 'Prescription has prism will forward a copy of my prescription'. Once your order has been processed please send a photo of your prescription via the contact us page. We do this because there are many ways to write the prism and we want to make sure its ordered correctly for you.
Infinity Symbol ∞ - this is another way of writing zero (no prescription) so simply select 0.00 into the corresponding section for either sphere or cyl.
Plano - this is another way of writing zero (no prescription) so simply select 0.00 into the corresponding section for either sphere or cyl.
You typically start to get the add part to a prescription when you hit 40+ and it is a measure of the amount of magnification you require to read.
The add is a plus (+) power which identifies how much extra addition (magnification) a glasses wearer requires (on top of their distance prescription) in order to read comfortably at close up distances, such as reading.
If you require reading glasses you take the addition value and add it onto the Sphere value of your distance prescription.
If you are unsure on your prescription you can upload a photo and send it into us to info@extreme-eyewear.co.uk and we can help you with your order.