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Adjustable-Focus Glasses Can Replace Bifocals
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."
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"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
I've been wearing glasses for over 35 years since kindergarten, and about two years ago, I got progressive lenses. Sure, they were a bit strange at first, but within a day, I just "got it" and I think they're great! By simply doing "micro adjustments", I can get pretty much anything into focus very quickly.
I really don't see what the big deal is. Can someone please explain why progressive lenses are so despised?
My mom always said, "Jim, you're 1 in a million." Given the current population, there are 7000 of me. God help us all!
Don't use cleaning fluid, tissues, or even those special cloths. Use soap and water only. Run water over your lenses to get the larger dust particles off, then wet your fingers and apply a couple of drops of dish detergent to them. Use this to get any remaining dust and oily residue off the lenses by rubbing the lenses with your fingers. Rinse the lenses under running water. Repeat as required. You can shake most of the water droplets off, and if you want to get rid of all of them, dab the lenses with a soft cotton towel. You lenses should remain scratch free for years.
and if you want to get rid of all of them, dab the lenses with a soft cotton towel.
Or use distilled water as the final rinse.
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?
They do apply a local anesthetic to the eye, but you are otherwise fully conscious and alert. They merely use a steel contraption to pin your head and shoulders down. ;)
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I was once warned that dish soap damaged some of the coatings applied to the lenses - not sure how accurate that was or how relevant it is today.
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There's also soft toric lenses for astigmatism.
I too have astigmatism and can wear Toric lenses to (mostly) correct it. Been wearing them for several years now, and I'm pretty sure my astigmatism is pretty bad. Never been recommended hard lenses. Perhaps your eye doctor is just old and not up to date? Or maybe I'm wrong in that only mild astigmatism can be corrected in soft lenses.
"Something's wrong with you...and I hope we never do meet again." - Deftones When Girls Telephone Boys
Yes, the lens stiffens with age. (There was a competing theory that it grows with age, and that focus problems arise because the focus mechanism doesn't have enough range of motion to adapt, but that apparently hasn't been borne out by further studies.
No, in general, lens replacement does NOT give you back focusing ability. There's one type of lens (Crystalens, referenced upthread) that restores accommodation for some recipients, but results vary widely, and regular replacement lenses don't accommodate at all.
What I *really* need is a new pair of eyeballs.
Not your eyeballs, just their lenses. They have soft contacts for astigmatism now, but if you have the money for it a CrystaLens is the way to go; I have one in my left eye and it's fantastic.
Its amazing how science has in some cases passed science fiction. In Star Trek IV there's a fictional drug called "retinox" that cures age related presbyopia by (presumably) softening the lens, and since Kirk is allergic to retinox, he has to wear reading glasses. One would think that McCoy could just transport Kirk's crystaline lens out and transport a CrystaLens into it, but the si-fi writers didn't forsee this new tech (it was FDA approved in 2003).
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You're correct; the "certain type of cataract surgery" is a new implant approved by the FDA in 2003. The older implants, the ones insurance covers, won't focus. But by the time you need cataract surgery your eyes won't focus anyway.
I have one of the new ones in my left eye. My surgeon said my outcome was better than average, but I'm better than 20/20 at all distances. I see better than most 20 year olds!
BTW, the new lenses move, on struts, making them devices. This means if you get these implants you're a cyborg.
Resistance is futile.
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Why not try laser correction? I used to have astigmatisms in both eyes (one significantly worse than the other). Laser surgery completely removed my dependency on eyeglasses.
Now that I'm getting older, I'm finding my arms a little too short ;). So a pair of reading glasses that can adjust as my presbyopia progresses would be greatly appreciated.
- Despite popular opinion, I am not perfect.
The Canon EOS 3 (and probably the 1V) had a feature whereby the camera would lock focus depending on where the eye was pointing while using the camera. These were both film cameras as well btw just to show how old this tech is.
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I've already had the surgery. Not keratomy, but a CrystaLens IOL (details at the link). It cured my extreme nearsightedness, my age related farsightedness, and my cataract. I have better vision than most 20 year olds.
They have improved the IOL I had implanted since I had the surgery, but I'm VERY happy with it. My vision is better than 20/20; last eye exam I was 20/16 at distance and 20/12 close up. I was 20/400 before the surgery. Sadly, I only got one eye done. Best thousand dollars I ever spent (insurance paid the rest; if I had one of the old fashioned IOLs they would have paid the whole bill.
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