You must be talking about Transitions. I have a pair of them and they do darken outside, but its according to the UV, not the light, which prevents them from changing indoors and also prevents them from getting real dark in the car. Most windows in cars have a UV filter built in, so Transitions won't get as dark as most people would like for sunglasses while driving. I like my Transitions for when I'm in and out. They darken almost immediately as soon as the sun hits them, but it takes longer for them to clear up once you're inside. But for when I'm driving, I have a second set of prescription sunglasses for when my Transitions lenses aren't dark enough.
Years ago, Photogrey Xtra lenses were very popular. These are glass lenses (instead of plastic or ploycarbonate) and they darken according to the light, which means they DO darken inside and they DO darken in your car. The problem with the PGX lenses is that they are extremely heavy, and lenses made of glass at the least safest when it comes to shattering. Most people want their glasses to be comfortable and light weight and glass does not offer that, especially to those who have stronger prescriptions. Where I work, we see a few people who still ask for the old PGX glass lenses because they ARE more durable when it comes to scratching. We have quite a few people who work in foundries, or in environments where they can't really be choosy about what they use to clean their lenses, so they opt for glass because they grab anything to wipe them and they don't scratch.
Ask your eye care professional about Transitions lenses and see if they are right for you...
2007-05-29 03:19:11
·
answer #1
·
answered by ♥♥Mrs SSG B♥♥ 6
·
2⤊
0⤋
Yes they definitely exist; I have two pair! They have been around for quite awhile - you can even get them over here in the Middle East where I live. I forget the optical name for them, but you need to go to a good optician (look in phone book) and inquire about them. My glasses are prescription, because I need a correction for near-sightedness, and I asked my doctor to add the tinting option to the lens as well. It may be that you need a prescription to buy them. Not sure, but the place to start is at an optician's store and ask about them. You don't need the name; they'll know what you mean when you describe them. It is pretty cool to be able to walk out in the sun and have the lens darken immediately, then walk back inside and have them go clear. They are a bit spendy however.
2007-05-29 00:13:45
·
answer #2
·
answered by Jan N 4
·
0⤊
0⤋
The main player in this is Transitions-turns to 87% sunglass tint in about 38 seconds...but beware, it needs ultraviolet light to change, so it won't change in the car. Your car windows are UV protected.
2007-05-29 03:08:03
·
answer #3
·
answered by kartouche 4
·
2⤊
0⤋
Photo tinted lenses. I have them.
Most opticians stock them. I've never noticed mine taking a long time to change.
2007-05-29 00:12:15
·
answer #4
·
answered by True Blue Brit 7
·
1⤊
0⤋
These have been available for decades and yes, they really do work. You can get them at any eye doctor -- optician, ophthalmologist, whatever.
2007-05-29 00:17:06
·
answer #5
·
answered by luvrats 7
·
0⤊
0⤋
Photo-chromatic lenses. Trouble is they take a loooooooooong time to change - not like on the ads!
2007-05-29 00:13:08
·
answer #6
·
answered by Anonymous
·
0⤊
2⤋