Transition lenses, which automatically darken when exposed to the ultraviolet (UV) light of the sun and revert back to clear at night or indoors, have all but revolutionized the eyewear industry. For corrective eyewear users, they can eliminate the hassle and expense of two separate pairs of glasses, one for standard use and one that blocks harsh sunlight.
The Pros and Cons of Transition Lenses
Transition (or photochromic) lenses have not, however, rendered traditional lenses obsolete. This is because the benefits of photochromics must be weighed against their potential drawbacks, and they aren’t always the perfect choice for everyone.
To see if they’re the choice for you, let’s examine the pros and cons of transition lenses:
- They automatically adjust to lighting conditions without any effort on behalf of the wearer.
- They come in two different colors, brown and gray. Both styles function exactly the same and the choice of color is strictly a matter of individual preference.
- Regardless of their state – fully clear, fully tinted, or anywhere in between – photochromic lenses provide 100% protection from both UVA and UVB rays.
- They react only to ultraviolet light, so will not accidentally darken when exposed to most forms of artificial lighting, indoor or out.
- Photochromic lenses are fully compatible with Anti-Reflective coatings and are available in virtually every lightweight lens material and design.
- They are available in both and non-prescription form, and in a variety of specialty applications, such as bifocals and progressive lenses.
- Many current automobile windshields are designed to block ultraviolet light. Therefore, photochromic lenses typically do not darken fully when worn inside a vehicle. You may require a separate pair of sunglasses or clip-ons for driving to achieve a comfortable darkness level.
- They do not adjust instantaneously. Your eyes are exposed for a short time when you first encounter sunlight, and shaded for a period when you enter a darkened room from outside
- While most of the transition takes place in the first minute, photochromics can take up to fifteen minutes to reach their fully darkened state and another fifteen minutes to fully clear again.
- They react differently in different climates. Photochromic lenses will reach a darker state at cold temperatures than they will at warmer temperatures.
Consider these pros and cons when purchasing your next set of eyeglasses to determine if transition lenses are the choice for you.