In terms of eye glasses, many choices are now out to consider. Technology has became active in many areas and when you are looking forward to know the correct lens for your eye glasses, it is important to have an idea about PD or Pupillary Distance. What is PD? PD is important because without it, corrected lens eyeglasses cannot be made. It is said to be useful in seeing the position the optical center of the lens when it is made. If interested in ordering for prescription eyeglasses, you need to request for PD if there is No PD for you from Opticians. You are welcome to shop and enjoy your new eye wear and all you need is to trust Zenni: the #1 online eyeglasses store.