We start off measuring the placement of your eyes with a pupilometer. There are many different versions of pupilometers in the optical industry. Illustrated below is a picture of an Essilor pupilometer. It is always nice to start with a pupilometer to obtain a pupilary distance as a reference point. The pupilometer sits on the bridge of your nose and does not fit like an eyeglass frame.     People who have experienced nose injuries may have it sitting crooked on their faces giving inaccurate readings. I use a pupilometer only as a starting point in my fitting of eyeglasses. A pupilometer is definitely not an accurate way of measuring a person’s monocular pupilary distance. Don’t misunderstand what we are saying here; they are definitely good machines and very helpful. A pupilometer can be relied upon for most single vision orders. However, when it comes to fitting progressive and invisible lenses, the margin of error in monocular pupilary distance is much less and you have to go to the second step of doing the fitting crosses on the lenses to ensure the accuracy of the placement of the eyeglass lenses. The placement of the eyeglass lenses is so important to tap into the optics of these beautiful eyeglass lenses. If you are in a dispensary that does not have a pupilometer, you can always start by using a PD ruler and then switch over to the fitting cross method.   © 1997-2008 VISIONFOREGOLFING.COM AND TIMED DESIGNS, INC. ALL RIGHTS RESERVED