In order to measure the Pupillary-Distance of your old glasses, you need to have something ready firstly, including a mirror, a millimeter ruler and sometimes markers and erasers. Now, look straight at the mirror, and then place a dot in middle of each lens or at the mirror at your pupil's center. Secondly, you can take your measurement by using the ruler to measure the two dots. keep it in mind that you need to keep your face muscles relax and the help of your friends will be perfect. In general, eye doctor will provide the current prescription and PD of your old glasses if you need. By the way, the common males' PD ranges from 55 to 65, while women are around 60.
Well, there are some tips you can just follow. First, you can apply a ruler, so that you can measure the overall width at the widest point. In common, it should be the temple of an old pair of glasses. Of course, you should lay your glasses on a table with the arms open and lay a ruler across the arms with the millimetres nearest the front of your glasses to measure. In that way, the number can be accurate. And then, just remove the lenses from your old glasses by unscrewing the screws that hold the frame together. But on the other hand, you need to remember that you should not force them out with your thumbs or fingers in case of injury. Anyway, just have a try.
Step 1: Stand with a friend facing you and place a millimeter ruler on the bridge of your nose. Keep the rule "0" measurement is exactly in line with the center of your left pupil. Hold the ruler straight.
Step 2: Let your friend read the measurement between the left pupil and the right pupil while you look straight ahead.
Step 3: For measuring a PD with high accuracy, please do it 3 times and take an average number of them as the final PD measurement.
For those requiring bifocal or progressive lenses, we strongly recommend you get this information from your optician to ensure the accuracy of your glasses.
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