Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
Transcript of Transition Lenses
are lenses that darken on exposure to ultraviolet radiation. Once the UV ray is removed, for example when you walk inside, the lenses will gradually return to their clear state. They can be made out of several different materials, including glass, polycarbonate, or another plastic. How do they work? The glass version of transition lenses are able to work correctly through the embedding of microcrystalline silver halides (like silver chloride), or molecules in a glass substrate. Plastic transition lenses must use organic photochromic molecules in order for them to change back to their clear state. The reason these lenses darken in sunlight but not indoors, is that room light does not contain the UV (which is a short wavelength light) found in sunlight. Automobile windows also block UV so these lenses would darken less in a car. Photochromic lenses are not entirely transparent, specifically they filter out UV light, which our eyes cannot see anyways.
Who came up with it? The glass version of this type of lenses was first developed by Corning Inc. in the 1960s. More recently, plastic versions of these lenses have been commercialized. The first of these was the Photolite lens sold in the early 1980s by American Optical Corporation. But the first commercially successful plastic photochromic lens was introduced by Transitions Optical in 1991. Conclusions Without UV protection, your eyes are exposed to
the harmful and damaging rays from the sun. Too much exposure to UV rays can damage parts of your eye, like the lens, cornea, and retina. Transition lenses block 100% of all UVA and UVB rays, helping to decread the risk of any damage to your eyes. Therefore, Transition lenses are proven to help you to not only have sharper vision, but better protected from other factors that may limit your ability to see.