Adjustable-Focus Glasses Can Replace Bifocals 220
Posted
by
kdawson
from the doctor-my-eyes dept.
from the doctor-my-eyes dept.
Hugh Pickens writes "The NY Times reports that inventor Stephen Kurtin has developed glasses with a mechanically adjustable focus that he believes can free nearly two billion people around the world from bifocals, trifocals and progressive lenses. Kurtin has spent almost 20 years on his quest to create a better pair of spectacles for people who suffer from presbyopia — the condition that affects almost everyone over the age of 40 as they progressively lose the ability to focus on close objects. The glasses have a tiny adjustable slider on the bridge of the frame that makes it possible to focus alternately on the page of a book, a computer screen, or a mountain range in the distance. 'For more than 140 years, adjustable focus has been recognized as the Holy Grail for presbyopes,' says Kurtin. 'It's a blazingly difficult problem.' Each 'lens' is actually a set of two lenses, one flexible and one firm. The flexible lens (near the eye) has a transparent, distensible membrane attached to a clear rigid surface. The pocket between them holds a small quantity of crystal-clear fluid. As you move the slider on the bridge, it pushes the fluid and alters the shape of the flexible lens."
How is that an improvement? (Score:5, Insightful)
The glasses have a tiny adjustable slider on the bridge of the frame that makes it possible to focus alternately on the page of a book, a computer screen, or a mountain range in the distance
Whowever designed this has obviously never worn progressive lenses. In real, ordinary life, you don't "decide" to focus on something for a minute and adjust the slider accordingly, you adjust your focal point *all the time*, unconsciously. What progressive lenses do is allow your neck muscle to "emulate" what your eye muscles would normally do if you weren't an old fart.
I just don't see myself (pun intended) spending the day with a finger on the rim of my glasses to do the same. If I want to be comfortable for an extended period of time in front of the computer, or to drive, I put on my near or far glasses. For the rest of the time (90% of my day), I put on the progressive glasses. Perhaps the adjustable lenses would allow me to have one pair of comfy glasses instead of two, but I ain't giving up my progressives. At any rate, my reading glasses are on the table, and my driving glasses are in the car, so it's not really a problem in the first place.
(On a side note, I've just realized I'm talking about my presbyopia on Slashdot, and the dreaded word "middle-aged" comes to my mind.)
Re:Crystalens (Score:2, Insightful)
What's it like to get a shot in the eye? I assume they anesthetize you so that can't flinch or blink. But are you conscious? It seems like a waking nightmare to watch a needle slowly approach your eyeball and there's nothing you can do about it.
I suppose it's a pretty routine operation, but yikes, the needle in the eye...
Re:How is that an improvement? (Score:5, Insightful)
What you're failing to realize is that this is the first step towards glasses that adjust their focus automatically.
Right now it's done manually. Just like we used to manually card wool.
Given time, the electronics needed to measure where you're looking, the distance to it and adjusting the focus will be built in to the glasses.
Great! Lenses that look like a FULL Coke bottle. (Score:4, Insightful)
I really, really want adjustable-focus lenses. But I don't want heavy lenses, and I don't want large, round lenses.
I'm hoping these folks [pixeloptics.com], linked in TFA, can deliver. Electronic focus sounds a lot more appealing and reliable.
tiny slider (Score:5, Insightful)
The glasses have a tiny adjustable slider on the bridge of the frame
Good thing the over-40 crowd is well-known for their dexterity and ability to accurately manipulate tiny adjustable sliders.
Violates the KISS Principal (Score:3, Insightful)
Re:Cool, but... (Score:2, Insightful)
My rigid plastic lenses eventually develop small scratches no matter how careful you are.
I first started wearing glasses half a century ago when there were no plastic lenses in glasses, and when the plastic ones came out I had the same trouble as you - they scratched too easily, so since then I always insisted on glass, despite the fact that they're a whole lot heavier. I got contact lenses in 2002 and surgery in 2006; the surgery is the best route.
If you have a spare $15,000 you can get the surgery that will completely correct your myopia and presbyopia. Glasses suck!
Re:Cool, but... (Score:3, Insightful)
> Use soap and water only.
The problem is, in the real world there's no such thing as "soap". You have to buy a retail product and they contain perfumes, colours, moisturisers, anti-bacterial additives etc... Which ruin your glasses.
I've taken to using a microfibre cloth which somehow seems to suck everything off without needing any liquids. It works quite well, but a good one is hard to find.