With traditional prescription lenses such as progressives, bifocals and multifocals, different areas in the lenses offer correction for different types of vision: distance, mid-range and near. You look through different parts of the lens to see at different distances.
With adjustable glasses, however, you have one lens that varies depending on where you are looking, and how you adjust it.
These glasses are known as adjustable eyeglasses due to the adjustment dials that help you vary the viewing distance for far- and nearsighted correction in a single pair of glasses. Depending on your specific needs, you can experience improved vision for driving, reading, working on your computer, or using your eyes in a thousand other ways.
How Do Adjustable Eyeglasses Work?
The central mechanism that helps adjustable glasses work is the fluid-filled lens technology that allows a person to adjust the power of the lens based on the type of vision they need for a given situation. The wearer will twist the dial until they see as clearly as possible.
Each lens has a sort of membrane that can be adjusted outward or inward by adding or removing fluid from within it.
The liquid is contained in a small syringe that is attached to each arm of the glasses. Moving the dial will either pump fluid in or remove fluid from the lens. Fluid entering the lens will increase the lens’s power, correcting for farsightedness. Pumping the fluid out corrects nearsightedness.
Advantages and Disadvantages of Adjustable Glasses
Though the affordability of adjustable glasses can be quite attractive, as can the fact that they require no prescription or eye exam, there are a number of drawbacks that may offset these advantages.
Because of the way the frames are constructed, with the dials on the sides and fluid in the lenses, frame selection is low, and they're usually not as attractive as traditional glasses offered by a local optometrist. On top of this, it can be quite difficult to adjust the lenses to exactly meet your visual needs at any given time. This can make vision with these lenses slightly lower in quality compared with most prescription glasses.
Overall, the affordability and ease of access make adjustable glasses a fine option as a back-up, but they certainly shouldn’t be considered your primary form of vision correction day-to-day.
Visit our local eye care clinic for all your vision needs today.