Pupillary Distance (PD)
How do I obtain my PD?
The Pupillary Distance (PD or sometimes referred to as Optical Centres - OC) is the horizontal measurement between your pupil centres. We need the PD so that we can accurately place the lens in the correct position in front of your eyes to ensure maximum clarity of vision.
- Ask your Optician for it. Although he is NOT obliged to write it on your prescription, your PD (or OC) will be written somewhere on your sight test details or your last spectacle dispensing. The optician is OBLIGED BY GDPR RULES to supply these documents free of charge when requested.
- Measure it yourself or ask a friend to help. Use the guidelines below.
Help to measure your own PD (Pupillary Distance)
Firstly, to measure your own PD you will need a ruler on which the scale can be seen easily. Rather than trying to measure the distance between your pupil centres, it is far easier to measure the distance between the edge of the coloured parts of your two eyes as shown by the red arrows in the diagram below.
Method to measure your PD yourself:
- Stand about a foot away from a well lit mirror without spectacles.
- Hold the ruler horizontally and firmly against the bridge of your nose.
- Align the zero on the ruler scale with the outside edge of the coloured part of one eye. (see diagram)
- Glance across and look at where the inside of the coloured part of the other eye lines up with the ruler. (see diagram)
- Repeat a few times to ensure some consistency and improve accuracy.
If you cannot see yourself and the ruler clearly in the mirror, ask a friend to help.
Method for your friend to measure your PD:
- Ensure you are standing or sitting directly in front of the person to be measured, about a foot away and at roughly the same height.
- Place the ruler so it rests on the bridge of the nose and firmly against the forehead.
- Ask the person to look directly at your eyes.
- Align the zero on the ruler scale with the outside of the coloured part of one eye (see diagram).
- Keep your head still and just glance across to where the inside of the coloured part of the other eye lines up with the ruler.
- Repeat a few times to improve accuracy.
Typically, a woman would have a PD of about 61mm whilst a man would have a PD of about 64mm, but this can vary. For example, Adrian’s PD is 68mm, whilst his wife’s is 64mm.
NOTE: If your PD is greater than 70mm, insert options will not be suitable for you because you would be looking through the extreme edge of the optical lens (the insert is too small for you). A Direct Glaze spectacle is the best option for you.