The Pupil Distance (PD) is the distance between the centers of each of your pupils of the eye. It can be expressed in two ways: the total deviation and the two half gaps. Normally the opticians need to know your pupillary distance in order to focus your eyeglasses during installation.
The PD will position the lens to mount over your pupils. As Pupil Distance (PD) is the difference between the middle of your two pupils of your eyes, it should be more precise and opticians usually measure the right half-distance (RPD) and the left half-distance (LPD). They represent the distance from the middle of your nose. The pupillary distance usually ranges from 25-30 mm depending on the shape of the face.
There are 4 methods to measure your PD:
- Ask your eye doctor to measure
- Reading on the bill of your last pair of eyeglasses
- Measure with the help of a friend
- Request the optician who made your last pair of glasses
During your consultation, simply ask your eye doctor to measure your PD, this solution is the easiest and safest way to accurately know your pupillary distance. The opticians have a pupilometre at their disposal that allow them to measure your pupil distance. The PD will helps you to get the clear vision from your eyes.