When glasses are initially manufactured, all of the frames are made in a similar, standard way. However, depending on the size, shape, and contour of your face, there may need to be adjustments made to the frame to allow the glasses to fit better.
Frame Shapes
One thing that cannot be adjusted is the shape of the frame. The frame which holds the plastic lens in place can be square, rectangular, circular, or oval.
When choosing the shape of the frame, it is important to consider how the frame shape will impact the way the glasses fit.
For instance, if you choose a square frame and have high cheekbones, the frame may rest on your cheekbones at times. While adjustments can make the frame sit somewhat higher, it is more important to select a frame shape which already works well with your face.
Frame Materials
In addition to the shape of the frame, the material that the frame is made from is also important when considering the possibility of adjustments.
An all-plastic frame is easily adjusted and manipulated in many ways and directions, while a metal frame will require more force and precision to adjust.
Alternative frame materials such as buffalo horn or wood may not be able to be adjusted much at all after production.
Adjustments for Tilt of Frames
A major way to adjust frames is to change the tilt of the frame. A frame will usually be tilted such that the top of the frame is more forward than the bottom and that the sides wrap around to follow the curve of the face.
Both of these tilts can be adjusted to improve the way a pair of glasses is fitting.
If the glasses are sitting too close to the face, the pantoscopic (vertical) tilt can be increased and move the frame further from the face.
If the glasses are not fitting securely and are too loose, the faceform (wrap around) tilt can be increased to have the glasses fit tighter on the face.
Adjustments for Frame Temples
The temples or legs of a pair of glasses are able to be adjusted in many ways and can be used to change how the glasses fit without changing the way the lenses are positioned.
The temples are designed to rest behind the ears and not touch the side of the head until right behind the ear. They should not be heavy on the ears and should not compress the sides of the face.
Adjusting the temples can align the frame to be centered over both eyes by moving one lens up or down.
Bending the ends of the temples is a common way to allow the glasses to be more secure on the face, especially with children.
If the glasses are uncomfortable or are causing pain because of the tight fit, the temples can be adjusted to fit looser and relieve the discomfort.
How to Adjust Your Glasses
Glasses should only be adjusted by a trained professional such as an optician or optometrist.
Bringing your glasses into an optical store will allow the professional to evaluate the fit and make needed adjustments.