What to Expect at an Eyeglass Fitting
If you’ve never had eyeglasses before, you may not know what to expect when you leave the optometrist’s office with your prescription. Knowing what to expect from an eyeglass fitting can help you be better prepared to find the pair of prescription eyeglasses that will look right on your face and help you see properly.
In order to ensure that your eyeglasses will properly correct your vision, there are a few measurements the optician will need to craft your glasses. While you may find some of these measurements on your eyeglass prescription from the optometrist, this part of the form is often left blank.
The first important measurement is the pupillary distance (PD) and represents the distance between your pupils. Since not everyone has a perfectly symmetrical face, it may also be necessary to get your monocular pupillary distance. For instance, if your PD is 32 millimeters, it’s possible that your monocular PD could be 15 millimeters on the left and 17 millimeters on the right instead of a symmetrical 16 millimeters on both sides.
The final measurement you’ll need to get is your pupil height. This is simply the distance in millimeters between the center of your pupil and the bottom edge of your eyeglass lens. As with the PD, this won’t always be the same for each eye.
The way you get these measurements will depend a great deal on where you go to get your prescription eyeglasses. In many eyeglass retail stores, the staff will use a piece of handheld equipment that you look into. While you focus on an object such as a hot air balloon or a certain color dot, they can look into the other side to get your pupillary distance. In other places, you may find that they simply hold a millimeter ruler up to your face to get the numbers the old fashioned way.
Note: If you plan to order your prescription eyeglasses online and your PD wasn’t on the prescription, the ruler method may be your best bet for getting accurate measurements.
The final set of measurements you’ll need are those of your eyeglasses themselves. While you may not be aware of it when you pick up a pair to try on, each set of glasses has three unique measurements. These represent the frame size (the part that circles your eyes), the bridge size (the part that goes over your nose) and the temple length (the pieces that go over your ears).
Knowing these measurements can be helpful when you’re looking for a pair of glasses that don’t slip forward or don’t pinch your nose so much. Depending on the maker of your eyeglasses, the measurements could be fully printed on the inside of the temple. In other cases, you may have to get the bridge and frame size from the inside of the bridge and the temple length from the inside of the temple. If you see 50/12/135, for example, this means that your frames are size 50, the bridge is 12 and the temples are 135 millimeters long.