<div class="_help_font_site selected-art-author"> <p><strong>What is PD?</strong><br /> &nbsp;</p> <p>PD stands for Pupillary Distance, which is the distance between your pupils in millimeters. PD is very important for accurately fitting your lenses to achieve visual clarity.</p> <p>Generally, PD numbers do not change for adults. The average PD range for adults is 55-75 mm and for kids is about 42-55 mm. A difference of 2-3 mm is acceptable.</p> <p>&nbsp;</p> <p><strong>How to measure PD?</strong><br /> &nbsp;</p> <p><iframe height="315" src="https://www.youtube.com/embed/KpcN94kf5j0" width="500"></iframe></p> <p>We highly recommend checking your PD with your doctor, especially for bifocal or progressive lenses.&nbsp;</p> <p>You can also measure the PD by yourself.</p> <p><strong>Download a printable PD ruler and check how to measure the PD <a href="https://df5apg8r0m634.cloudfront.net/email/2020/0513/MKmAzAK9pUjy4dEX.pdf">HERE</a>.&nbsp;</strong></p> <p>&nbsp;</p> <p><strong>How to read PD?</strong><br /> &nbsp;</p> <div id="intact_31"> <p>Your PD may be written in three ways:<br /> 1. PD (OU), written as &quot;64&quot;, means the Binocular PD which is for both eyes.&nbsp;</p> <p><img alt="" src="https://df5apg8r0m634.cloudfront.net/images/2019/0322/fBdfyaqAZu.jpg" /></p> <p>2. DUAL PD,&nbsp;or monocular PD, consists of two numbers and is the distance between the centers of each pupil to the bridge of the nose<br /> Dual PD is written as two numbers, for example, &quot;32/32&quot;, the first one &quot;32&quot; represents the PD for the right eye, and the second one &quot;32&quot; represents the PD for the left eye.&nbsp;</p> <p><img alt="" src="https://df5apg8r0m634.cloudfront.net/images/2019/0322/iHqmaWSh5P.jpg" /></p> <p>3. Sometimes PD is written as &quot;62/59&quot; or they are labeled &quot;Far&quot; and &quot;Near&quot;. Your PD is usually measured for distance vision, which is &#39;Far PD&quot;, or &quot;62&quot; in this example. For reading glasses, doctors measure your &quot;Near PD&quot; or &quot;59&quot; in the example.<br /> Always enter your &quot;Far PD&quot; for distance vision eyeglasses and enter your &#39;Near PD&quot; for your reading glasses only. For most people, the difference between Far PD and Near PD is about 2-3mm.<br /> <br /> <strong>How to fill in PD?</strong><br /> <br /> 1. If you only have one PD number, such as &quot;64&quot;, please select 64&nbsp;when fill in your prescription.&nbsp;<br /> <img alt="" src="https://df5apg8r0m634.cloudfront.net/email/2020/0421/PppBOeVpJQYo4ZmB.png" /><br /> <br /> 2.&nbsp;If your prescription provides Dual PD, such as &quot;32/32,&quot;&nbsp;please click &quot;Two PD numbers?&quot; and fill in 32/32.<br /> <br /> <img alt="" src="https://df5apg8r0m634.cloudfront.net/email/2020/0421/NrFpnCSU4FfQ7U7a.png" /><br /> <br /> 3. If your PD is written as &quot;62/59,&quot;&nbsp;then &quot;62&quot; is your far PD and &quot;59&quot; is your near PD. Please enter your &quot;Far PD&quot; for distance vision eyeglasses and enter your &quot;Near PD&quot; for reading glasses.</p> </div> </div>
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