Contact lenses provide a number of convenience advantages over glasses, but one they come up short in one area—you can’t get contacts that automatically adjust to the sun’s UV light and darken, like the photochromic lenses many bespectacled people enjoy. But that could soon change: Researchers in Singapore led by Jackie Ying have now created a contact lens that responds to UV light.
Transition lenses for glasses are coated with a dye that is transparent when out of the sun, but responds to UV light by changing shape and darkening. Few previous attempts have been made to design transition contact lenses, largely because it’s difficult to apply dye coatings uniformly to the delicate, soft surface of a contact lens. Ying and her colleagues got around this by developing a contact lens that embeds dyes uniformly throughout the material [Technology Review].
The scientists crafted their contacts with a structure that includes nano-sized tunnels to hold the dye. The lens’ porous structure allows the dye to change shape quickly, which team member Edwin Chow says reduces response time. “When your car suddenly goes into a tunnel, the amount of light is very dim, so you need your lenses to transform back immediately,” says Chow. [Technology Review].
First things first: the team tested its lenses on rabbits to make sure they were bio-compatible, and tests continue test to make sure the lenses don’t leak dye. However, there’s no word yet on whether near-sighted rabbits prefer contacts to glasses.
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Image: Institute for Bioengineering and Nanotechnology

November 10th, 2009 at 2:52 pm
So instead of looking like you are wearing sunglasses, as you would with transition lenses in glasses, with these contacts you would look like you had cloudy sclera? Doesn’t sound as nice
November 10th, 2009 at 6:16 pm
There are definitely going to be a few social hurdles to get around when marketing these.
November 10th, 2009 at 7:27 pm
This is revolutionary!! I can’t beilve it. this is too cool.
November 10th, 2009 at 8:42 pm
Considering that I have extremely light-sensitive eyes and could not wear contacts because one or the other eye would ‘roll’ up out of the light and knock the contacts out….
This is AWE-SOME! Go, researchers, GO!!! :)
I’d love to ditch the glasses….
November 11th, 2009 at 2:25 am
D Thakur, don’t forget that these lenses were developed in Singapore, where majority of the people have black or dark-colored iris. I’m sure if it resonates well in the Asian countrys (no side effects, no major complains etc), they will come up with lenses of other colors :)
November 11th, 2009 at 8:32 am
that could be too expensive! i wanna buy one
November 11th, 2009 at 10:23 am
how do i get in contact with them i’ll be a human guinea pig to test them contact lenses out
November 11th, 2009 at 1:26 pm
It’s about bloody time!
I tried contacts briefly, but had to go back to glasses because of sensitivity. I wasn’t too heart-broken as I missed my transition lenses and didn’t like always trying to remember to grab sun glasses before going out (my eyes are pretty sensitive to sunlight too).
It’s great to hear that maybe someday I’ll be able to comfortably wear contacts again sans sun glasses!!!
November 11th, 2009 at 10:37 pm
Does NOBODY here have S.A.D.??? Or live where it is cloudy?
I accidentally got transition lenses in my glasses ONCE. I took them back within 3 weeks—I would go out on a cloudy day to work in the yard, and despite a drizzle, the things would darken . Yes, I know, UV rays are out on cloudy days too…but the whole point of going OUTSIDE was to get more of what little sunlight there was, not be even more depressed! If you can’t see the garden you’re trying to weed it’s rather pointless! It gets dark enough here in the midwest for most of the year without my glasses or contacts adding the the eternal sense of doom. augh! And in NOVEMBER, to write about this, no less. I can feel my soul shriveling just thinking about dark contacts….ugh. ick. Off to go sit under my light therapy lamp.
May 10th, 2010 at 8:55 pm
these sound amazing. i have nearly perfect vision cept for when i walk outside on a cloudy day and i am blinded by the little light. just think how bad it is on a sunny day
October 26th, 2010 at 8:45 pm
Jessica:
I have the same thing! I have 20/20, but even if its really cloudy and the clouds are grey I still have to squint and my eyes water really bad. It even happens when Im inside under flourecsent lights at school.
March 16th, 2011 at 4:40 pm
This is awesome! I am always sailing and I can’t deal with sunglasses. Where can I get them though????