Factors That Are Important In Buying Spectacles Online – Pupillary Distance
Measuring your pupillary distance:
This measurement is the distance between the centre of your pupils that is measured in millimetres.
Opticians do not tend to give out this measurement as it encourages patients to buy their spectacles from them whereas you can buy cheap spectacles online or designer glasses at a fraction of the price online. It is usually recorded as 1 measure for example 60 (60mm) but can also be shown as R 29 L 31. When written in this way it is the individual distance from your right and left pupils to the center of your nose.
When Varifocals, High Prescriptions or Prisms are ordered the measurement is ordinarily split separately. On the whole, if you have a single vision prescription, it will be written down as one value.
If you do not know this measurement and don’t want to measure it yourself then most online opticians will make your PD the national average (63) for men and (60) for women.
Ask a family member or friend to physically measure your PD:
This is the easiest method for measuring you PD. To do this, ask a friend to sit opposite you and place a ruler against your forehead so that they can read off the markings from the ruler.
Next ask your friend to close their right eye and you then look directly into their left eye. Request your assistant to slide the ruler in order for the zero value is in the center of your right pupil and to hold the ruler very steady across your brow. Subsequently, you will need your associate to shut their own left eye and you will need to look straight into their right eye.
Your friend will then read off the measurement to the centre of your left pupil. And that is it! It really is that easy! Please see the diagram below to help you further.
Using your latest glasses to measure you pupillary distance with assistance from a friend:
You can put your spectacles on to judge for yourself how well they fit. Request your assistant to stand opposite you and mark on your lenses the placement of your pupils with a non lasting marker.
You should now see two lines directly infront of you whilst you are wearing your glasses. Merely, remove your sunglasses and measure the distance between the two markings. And that is it! If the measurement reads 6cm the PD distance will be 60. If the measurement is 6.3cm then your pupillary distance will be 63.
For Varifocal Measurement simply measure from your right eye to the middle of your nose and then from the middle of your nose to your left eye to obtain the required individual readings for your right eye and left eye. When buying non-prescription designer sunglasses this measurement is not applicable.