– Ed

The fit of your glasses on your face is vitally important: the reasons will be covered here. On collecting a new pair of spectacles, care should be taken that they are properly aligned and fit comfortably. This is something that should happen as a matter of course at any optometric practice. Spectacles won’t retain shape and remain comfortable indefinitely, and realignment would be necessary from time to time. Most optometrists will provide this service free of charge, and as a rule, no appointment is required.

The Optics

The way the glasses fit can affect the way you see. This is especially true in the higher power prescriptions. The distance the lenses are positioned from the eyes is very important. If the frames are constantly sliding down the nose, it not only moves the lenses further away from the eyes, but it also lowers the position of the optic centres of the lenses. In the case of multi focals, this can cause major irritations. The pantoscopic angle of the frames (see photo), is also important.


Poorly fitting frames can really detract from the overall appearance and the image you want to project. Frames drooping down on one side or fitting closer to one eye than the other, will look ugly. If the pantoscopic angle is wrongly aligned, it can drastically affect the general appearance of the frame.


It can be tough trying to get through a whole day, while spectacle frames are hurting you. Common causes of this are; nose pads poorly aligned, temples (ear pieces) not curling nicely over the ears to ensure a good fit. Sometimes, there may be a bend or twist on the bridge of the frames or the temples start pointing outwards from the taking-off movement with one hand. It is always better to remove spectacles using both hands.

Understanding frame measurements:

If you look on the inside of your glasses, you’ll find a number that looks like: 52 [] 18 135.

Lens diameter: 52mm:
The lens diameter is the width of the lens (in mm), measured from the bridge. It can be a matter of personal choice, but it’s also determined by your frame style.

Bridge width: 18mm
The bridge width is the gap above your nose between the lenses. It’s important that this is comfortable – too tight, and the glasses could pinch your nose; too loose and the glasses won’t be stable on your face.

Side length: 135mm
The length of the side is usually one of three standards – 135, 140 or 145mm. The side should be long enough to sit comfortably over your ears. Glasses with straight sides don’t always have this measurement indicated.

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