PD's and Lens Measurements
We'll measure your PD if your buying in-store !
Your Pupil Distance measurement (PD) is an important measurement measured in mm, and is the distance between one pupil to the other. When you are buying glasses or prescription lenses from us in-store you can rest assured that we will accurately take all the measurements needed including pupil distance measurements and fitting heights for setting Bifocal or Varifocal lenses.
PD's can be measured as a whole,
ie: 60mm in total from one pupil to the other,
or one eye at a time,
ie: Right 30mm and left 30mm totalling 60mm
although PD's differ from person to person.
An average PD would total 63mm for distance or multifocal wearers and 60mm for near or reading glasses requirements. PD's for an adult can range from 58mm in total to 70mm in total or there about. Your Optician may be able to help with this measurement for a small fee. We rely on this measurements accuracy which will provide best vision.
More helpful information about your prescription
What is a Sph or Sphere ?
Your Sph measurement is the magnifying power of your prescription lens.
What is a Cyl or Cylinder ?
Not all prescriptions have a Cyl measurement indicated but Cyl's are very common on most prescriptions. The Cyl is a curve on the prescription lens that fine tunes and makes vision appear sharp and clear.
What is an Axis ?
Not all prescriptions have an Axis, but if you have a Cyl indicated on your prescription, then you will also have an Axis measurement indicated too.
Axis measurements are in degree's from 1 to 180. Again, these work in conjunction with a Cyl measurement to give crisp sharp clear vision.
What is an Add or Reading Add ?
An Add is an extra amount of power needed to be added to the long distance
prescription for a Wearer of Varifocals, Bifocals, and sometimes reading glasses.
What is a Prism ?
Prism's are rare but some prescriptions include them. If you need a prism your prescription will indicate so, and this could be measured as a movement of the lens before mounting to the frame ie: 1 prism base out or in. 3 prism up or down, etc.
If you have a prism indicated on your prescription it is essential that it is include when your glasses are made. To save error you must use the upload prescription function on our site sending us a picture.