Photochromic lenses are an extremely convenient, cost effective and beneficial purchase for a number of reasons, although, there are some weaknesses. There are pros and cons of photochromic lenses and sunglasses, including those listed below:. Reaction Times — Although photo lenses reaction from clear to sunglasses is quite quick, typically within 30 — 60 secs, the reversal takes a little longer as much as 5 minutes depending upon the temperature of the lens which could be dangerous if entering a dark room or certainly inconvenient at best.
Photochromic Lens Temperature Dependency:. Cold weather also increases the time taken to return to a clear shade. Plastic photochromic lens molecules of silver and halide are usually layered or embedded evenly onto the surface of the lens providing an even shade of tint when darkening.
Glass photochromic lenses have the molecules contained within the glass and this can sometimes cause an uneven tinting effect on a lens with higher prescription due to the different thickness of the lens from one edge to the other. Can I use Photochromic sunglasses for driving? Standard photochromic lenses do not work inside a car due to the windscreen blocking out the UV rays which are needed to active the chemical process which causes the lens to darken.
A new lens has been brought to the market that can react inside a car or behind the windscreen without UV rays and uses daylight alone to trigger the reaction. These lenses are known as ' transition drivewear lenses ' which combine both photochromic and polarisation technology.
As the name suggests, they were invented for use in the car whilst driving and offer full protection from the suns glare during the day which makes them perfect for wearing whilst driving.
This image shows how transitions Drivewear photochromic lenses react in different conditions:. Photochromic lenses are available in many lens types, materials, coatings and designs, such as varifocal lenses , high index lenses and polarised lenses. When the structure of trillions of molecules changes at the same time, the entire surface of the lens appears to darken.
The end result is glasses that turn into sunglasses, then back again, with no intervention at all aside from sun exposure. In the past, this process took up to a full minute to complete.
But thanks to evolving technology, many photochromic lenses now transition from clear to completely darkened in as little as a few seconds. The process works in reverse when you step inside from the bright light outdoors. The dark tint of your photochromic lenses fades to clear over your first few minutes inside.
Yes, Transitions lenses work in virtually any frame and material: plastic, metal, rimless, semi-rimless, or full frames. Transitions lenses are compatible with anti-scratch and anti-fog coatings.
And not only are they compatible with anti-reflective coatings which reduce reflections off the lenses , but Transitions lenses are even better in reducing distracting, discomforting, and disabling glare, both indoors and out. Check with your eyecare professional or eye doctor to see which eyewear and lens options are right for you. Yes, Transitions lenses are a great option for children. Did you know that the average child receives three times the UV exposure as an adult?
Children are also more exposed to Harmful Blue Light than ever before with significant digital device usage and time spent out in the sun. All Transitions lenses help protect from Harmful Blue Light, both indoors and out. Ask your eyecare professional for more details. Also, nonprescription Transitions lenses are also available in some of the products in the Transitions performance sunwear line. Many insurance providers offer coverage for Transitions lenses as part of their vision care plan.
To find out what savings you can enjoy, it is best to contact your insurance provider. If you encounter any difficulties, please call Transitions Optical Customer Service at and someone will help register your lenses for you. What are Transitions Lenses? Are there different types of Transitions Lenses? How has the technology changed over the years? Do I have to worry about the photochromic technology scratching or peeling off my Transitions Lenses?
What affects the performance of Transitions Lenses? Transitions Everyday Lenses Performance. Are Transitions lenses as clear as an ordinary clear lens indoors? How dark do Transitions Lenses get? How quickly do Transitions lenses darken outside? How quickly do Transitions Lenses return to clear? How long do Transitions Lenses last?
Adaptive Lenses vs. Clear Lenses. Why should I wear Transitions lenses instead of ordinary clear lenses? How do Transitions Lenses differ from prescription sunglasses?
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