[2022 Edition: How to Choose Glasses/Sunglasses] PD (Pupillary Distance) I METRONOME

Hello, I'm Yamada from METRONOME-Tokyo Online, the official Japanese online store for METRONOME DESIGN INC., which sells METRONOME®, an eyewear brand founded in London.

Well, today I'll be talking about how to choose glasses/sunglasses again. I think that in many cases, you first choose based on the design and shape, but...

The thing you need to be careful about is the size. If it's a little bit off, it can be fixed, but if it's too big, it can be a strain on your eyes.

Also, there is a possibility that the width may not fit and the item may be too tight to wear. For this reason, our shop always lists the size on each product page.

When trying to find the best sized glasses/sunglasses, you should be aware of how closely the center of your eye matches the center of the glasses lens. Specifically,

It is also important to be aware of the "PD (Pupillary Distance)." This is the distance between your eyes, measured from the center of your eyes when looking straight ahead. When choosing glasses/sunglasses, what is the ideal condition?

The center of the eye is at the center of the lens.

This means that it is the exact center, including the vertical and horizontal widths.

For example, the distance between the centers of my eyes is about 65mm (measured by myself with a ruler). In this case, when choosing glasses/sunglasses, choose frames with lens width and bridge width as close to 65mm as possible.

This is because it is ideal for the lens to be aligned with the center of the eye .

Therefore, it is necessary to know the distance between the centers of the left and right lenses of the eyeglass frame.

The formula for calculating whether a frame matches your PD is: lens radius + bridge width + other lens radius = frame PD.

To put it simply, you just need to check here to see if the lens width and bridge width are close to your PD.

When you organize it, it becomes like this↓

Ideally, the lens and the center of the eye should be aligned.

1) For eyeglass frames, you also need to know the distance between the centers of the left and right lenses. 2) The formula to calculate whether a frame matches your PD is: lens radius + bridge width + other lens radius = frame PD.

In other words, you just need to check here to see if the lens width and bridge width are close to your PD .

For example, let's say the size of a certain pair of glasses/sunglasses is as follows:

Size (mm)
1: Lens width 46
2: Bridge width 22
3: Temple length 138
4: Lens height 38

Looking at the equation above, "lens radius + bridge width + other lens radius = PD of that frame," we get 1) 46 + 2) 22 = 68 (mm)!

The closer this number is to your PD, the better. Conversely, the greater the deviation, the greater the discrepancy in size, so you need to be careful!

It's fine if you don't mind a slight difference in size, but if you want to get prescription lenses, we strongly recommend measuring your PD (Pupillary Distance) .

This is because if prescription lenses are inserted when the PD is misaligned, it can easily lead to eye fatigue, etc. Therefore, if you are planning to get prescription lenses made, be sure to tell your optician that you would like to have your PD measured.

That's how to tell the size of your glasses/sunglasses.

So,

Yamada