Showing posts with label IPD. Show all posts
Showing posts with label IPD. Show all posts

Friday, July 22, 2011

How Do You Get Your PD?


What is Pupillary Distance?

Pupillary Distance (PD) is the distance in millimeters between the center of your eyes’ pupils. The typical PD range is between 54 and 74 mm. (Exceptions are there)
Your PD is needed for ordering glasses because it is used to custom-fit your glasses’ lenses to focus directly over your pupils, allowing you to see your personal best.

Measuring Your PD Yourself

If you can’t get to the eye doctor and still need your PD, follow these steps to measure your PD yourself.
Have ready: a straight ruler, a pencil, and a mirror
  1. Facing the mirror, place the mirror on the bridge of your nose, bringing the start of the ruler directly below the center of one eye’s pupil.
  2. Looking straight into the mirror, hold the ruler (keeping it steady and parallel to the floor!) and mark the location on the ruler of the other eye’s pupil.
  3. Measure the distance in millimeters between the two marks. This is your PD.
  4. Repeat this process a couple of times to ensure you have an accurate measurement.
If you have a willing assistant, you can simplify the process even further by having your friend measure your PD using a ruler. (Your job will be to stand still.)
Whether measuring with someone or alone, be sure to hold the ruler steady and parallel to the floor!




Monday, July 18, 2011

Simplified way to find diameter for a single vision lens!



NB: In case of different PD in right and left, use mono ocular PD and double it instead of taking IPD.