Your Prescription
Your prescription contains various information to ensure you get the best vision possible out of your spectacles. Don't worry if your prescription doesn't contain all of the following values, not everyone has an astigmatism for instance.
The sphere specifies the strength of lens required to correct your focus - a plus sphere to correct long-sightedness (hyperopia - difficulty focusing on close objects) and a minus to correct short sightedness (myopia - difficulty focusing on distant objects.)
The cyl and axis compensate for an astigmatism. So what's an astigmatism? An astigmatism is where the eye is shaped slightly like a rugby ball not a perfect sphere like a football. This just means the eye has difficulty focusing at certain angles.
The Add, short for Reading Addition, is the additional correction required for reading, this can be used to make either reading glasses or bi/vari-focal glasses.
A Prism is to try and correct a muscle imbalance (lazy eye) and some other conditions and indicates a more delicate condition. If your prescription contains a prism we recommend you have your frames glazed at your opticians because accurate measurements will need to be taken when you're wearing the frames. We are happy to sell you the frames unglazed of course.
The PD, or Pupilliary Distance, is the distance in millimeters between the center of your pupils, it's not such a major factor at low prescriptions but is very important for stronger prescriptions and bi/vari-focals. We always recommend providing an accurate PD and if your optician won't provide it we now have an online pupilometer you can use
You will sometimes see two values, one PD at distance and one PD for near vision (reading.) If you do just put the details in the notes section of your prescription.
Prescriptions come in many different formats, probably the most common is the GOS2 which can be a little unclear. The following example shows how to interpret it
Problems Entering Your Prescription Details?
If there are any other details on your prescription include them in the notes (or contact us on 0208 123 6858 or info@specsonthenet.com) and we'll do our best to accomodate you - but unfortunately we can't handle every prescription.
