Many patients confuse progressives and transitions lenses.
Transitions lenses help you ”transition” from light environments to dark. These lenses, the descendents of photogrey glass lenses, are plastic lenses that change from clear to dark gray when exposed to ultraviolet light (U.V.). Some transitions lenses turn brown instead. Unlike the old photogrey lenses they take just a few minutes to turn completely clear when coming in from the outdoors. Transitions lenses never stay dark leaving the wearer with that raccoon appearance common with the older glass photogrey lenses. The only limitation of this lens type is that they rely on UV light to turn dark. When driving your car the windshield forms a barrier to UV so the lenses often do not darken to an acceptable level while driving. Polarized sunwear is still the best for driving.
In a progressive lens, the amount of reading power “progressively” increases, as the wearer looks through lower portions of the lens. These lenses are a great replacement for old-fashioned bifocal lenses with a line and are perfect for general use. In addition to providing suitable powers for reading, progressive lenses provide intermediate powers that are useful for the instruments in a vehicle, sheet music, or the edge of the grocery store shelf from 3 feet. While many people wear a progressive lens for computer use, this usually requires the user to tip their head back to see a desk top monitor, which can lead to neck pain, numbness in the hands and other problems. While a progressive may be adequate for use with a lap top computer, specialty computer lenses are preferred for use with desktop computers because they help to protect the user from the neck and back pain associated with tipping the head back.
