Adjustable-Focus Glasses Can Replace Bifocals 220
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."
Cool, but... (Score:5, Interesting)
...how do you clean them?
I've had glasses for ages now. I clean them every day. My rigid plastic lenses eventually develop small scratches no matter how careful you are.
So how will these lenses with movin parts hold up when cleaned for every day for N years?
The FAQ claims:
I'm not impressed unless it's been proven over time...
Re:Cool, but... (Score:5, Funny)
My rigid plastic lenses eventually develop small scratches no matter how careful you are.
Sorry. I'll be more careful in the future.
Re:Cool, but... (Score:4, Interesting)
I suspect cleaning these "liquid-filled lenses" is no different than cleaning your liquid-filled calculator or LCD screen.
Not that this will help me. I have astigmatism which makes it virtually impossible to wear anything except hard lenses or hard contacts. What I *really* need is a new pair of eyeballs.
Re:Cool, but... (Score:4, Informative)
There's also soft toric lenses for astigmatism.
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Re:Cool, but... (Score:5, Informative)
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 [crystalens.com] 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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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.
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TruFocals can cure astigmatism [trufocals.com]
Re:Cool, but... (Score:5, Informative)
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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.
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Also, anhydrous alcohol is very useful, it doesn't leave stains and washes dust easily.
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Be cautious in using more aggressive solvents like anhydrous ethanol -- prolonged exposure or repeated use may damage or remove optical coatings from the lenses.
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I prefer uncoated glass lenses, so it's not a problem for me.
But you're correct, of course. Ethanol may damage plastics.
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Funny, but I do use lens cleaning fluid and I do use something supposedly even worse than lens cloth - I use plain Kleenex tissue. And after some 10 years I don't have a single scratch or mark on my lenses.
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Tried that. My lenses were a mess by the time I replaced them. Now, I'm going with the special cleaning pad option. If I wasn't diabetic I'd just get laser surgery, or at least contacts.
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> 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.
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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 wi
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If you are keen on surgery, don't do it yet. Hold out till the intra-ocular lens technology improves further. No point doing the keratomy stuff, since most people's natural eye lenses will harden/stiffen with age.
The current tech is OK, but my guess is the ranges of accommodation (diopters) will increase. You might even be able to get better than 20/20 vision
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I finally took the leap with wavefront Lasik and I see 20/15. When I get old enough to suffer from presbyopia, I'll probably just get ne
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If you had read the article you would know that they developed a *time machine* in tandem with the glasses so that they could prove their long-term durability.
Re:Cool, but... (Score:4, Funny)
Hey. That's why someone tagged this story !Presbyterians :-) Of course, the people who needed to know that couldn't read it... but still, awesome tag!
About time, too (Score:3, Interesting)
My presbyopia is such that I just do without spectacles for close work, and don monofocals for driving, etc. I have bifocals, but they irritate me to no end. If adaptive focus spectacles are reasonably-priced (no more than double the cost of good coated bifocals), then I'll be first in line.
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My PRK cured the myopia and astigmatism. But it turned out that the myopia cancelled the presbyopia, so now I need readers about 50% of the time. Luckily, I can use off-the-shelfs.
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My question is why if this was granted in 1999 [google.com] is it not in production today?
In the boring commodity world of eyeglasses, "they" are smart enough not to fall for an obvious submarine patent, unlike the fast paced world of I.T.
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.)
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Amen. This seems like a good idea...but for the things I do that don't involve sitting in front of a computer or a book, it'd be a disaster. Both driving, and to an even greater extent flying, involve repeated, regular, rapid changes in focus distance from close to far, and especially while flying, my hands have better things to do than stay up at the bridge of my nose adjusting how well I see.
I've worn bifocals since I was 16 years old. (Focus flexibility problems don't always start in middle age.) These n
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.
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Right now it's done manually. Just like we used to manually card wool.
Speaking of getting older, was wool carding the best analogy available or should I get of your lawn?
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It was the first thing that sprang to mind.
And if you think about it, it's quite apt, considering that turning raw wool into any kind of modern clothing is a very demanding process if you do it all by hand, yet you can probably go from sheep to sweater in an hour or less today, making a tedious process (manually adjusting the focus) into a highly automated one.
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was wool carding the best analogy available
Parallel parking (ugh!).
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In the old days you had to turn the engine manually to start it.
Nowadays there's an electric motor that does the dirty work for you.
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That's right -- soon the automatic adjustment will be as fast, accurate, and effective as the autofocus on your camera. Meanwhile, the battery pack and image processing unit on my belt will only have to be recharged twice a day!
Oh. Erm.
I hope you're not planning on driving with these.
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This would be really cool for controlling tint in glasses though. Those transition lenses that do this automatically don't really work well. I would love a pair of glasses that allowed me to manually adjust the tint.
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That problem has been solved for decades, if not longer. Two polarized lenses, one of which can be rotated relative to the other, produce the effect you are looking for.
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Ok, so can you buy them in a standard optometrists?
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That would leave you unable to read LCDs. A single polarized lens is bad enough in this regard: I use polarized sunglasses, and I have to align the LCD to be able to view it. Turn the LCD on its side (PDA or iPhone in landscape mode), and it goes black.
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Is that a function of the LCD, or of the cover screen? If the latter, you've just given me a use for dead LCDs, cuz I could use some polarized filter glass (or something like) over certain windows that presently annoy me. (And I haven't seen, at least not cheap, any large swaths of polarized glass for sale.)
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My wife got transition lenses specifically because she wanted to be able to use them while driving and didn't want a separate pair of prescription sunglasses to have to keep track of. Turns out, the transitions were completely useless for the one thing she wanted
Polarized sunglasses (Score:2)
Even leaves tend to look greener (since most of the reflections are blocked). Plus it's easier to look through the car windscreens to see other cars ahead.
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it works for cyclops...
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The glasses have a tiny adjustable slider on the bridge of the frame
I remember reading about these glasses in National Geographic.
They were designed for [mostly rural] third world markets where dispensing opticians are almost non-existent - and complex lenses priced out of reach.
The village elder would be quick to admit that they look over-weight and dorky even on him.
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I just don't see myself (pun intended) spending the day with a finger on the rim of my glasses to do the same.
When I was in my forties I'd pull my glasses down my nose to focus to read.
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Since they use a fluid lens as part of the design I'm looking forward to all sorts of novelty designs. Put some white sprinkles in it so you think it is snowing all the time. Add some tiny plastic fish and now your world is an aquarium! The possibilities are endless.
Because progressive lenses make me want to vomit (Score:2)
Well not really want to , but I might just vomit anyway. If you are comfortable with tunnel vision maybe progressive lenses are OK, but if you need to look at anything that is large or up close they are beyond awful. I tried them for a whole month and never got used to them , and even if I had adjusted to the point of no nausea or headaches they still would have been useless for anything other than reading business cards.
I have been wanting a pair of these since I first heard about them.
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Welcome to the older generation, slashdot style :)
And here I was going to whine about how progressive lenses never seem to be *quite* in focus, no matter how I bend my neck. I suppose it's a YMMV thing.
My other problem with all of 'em is that I really need glass, or water, or something equally clear. I *never* stop SEEING the plastic, even in the best polycarbonate lenses, and that haze over my vision bothers me. I can actually see my contact lenses as a faint haze (one slightly more blue than the other), m
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Notice how you now require several glasses for several ranges; one pair for close, one for far, and some progressive. You have to switch manually between those glasses. The invention now reduces the switch action to adjusting a slide.
No it doesn't. I'd still have to have progressives and a pair of magic-slider glasses. So instead of three pairs, I'd have two. Unless of course I can have glasses with 3 settings (progressive, fixed/near and fixed/far), in which case I'd gladly buy them.
Don't track accomodation, track vergence. (Score:2)
It would be lovely to track focus based on ciliary tension, but it'll probably be easier to measure vergence [wikipedia.org] and adjust focus correspondingly. We can already do gaze-tracking pretty well, and vergence in principle gives a much large signal with less noise than ciliary muscle tension.
Not a new idea by the way (Score:3, Informative)
Water-based eyeglasses [core77.com]
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Crystalens (Score:5, Interesting)
They're three years too late for me; I had a CrystaLens implanted [slashdot.org] in one eye in 2006. It is an adjustable focus lens that replaces the eye's natural lens, and it uses the eye's focusing muscles to focus.
Its drawbacks are first, you have to have surgery, and second, it's pretty expensive. It's affordable if you have cataracts, where insurance will pay most of the costs and even then the out of pocket expense to cover the difference in price between an old fashioned InterOptical Lens (IOL) and the new one.
Your eye actually has two lenses; the cornea and the crystalline lens. The latter is what focuses, until you reach your forties when it starts becoming stiff, too stiff for the eye's muscle to move.
These new reading glasses would be a boon to anyone with the old fashioned IOL, anyone who is afraid of letting a doctor stick needles in their eyeball, and anyone without about $6,000 to get one eye fixed. I'll bet they're expensive (haven't yet RTFA) but I'm sure they're cheaper than surgery, and like all new technologies, the price will come down in time. In twenty years you'll be able to get them for ten bucks in today's money, I'd be willing to bet.
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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...
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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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You will be assimilated. Resistance is futile! (Score:5, Interesting)
You're only semi-conscious; they drug you into what they call "twilight sleep". They use anesthetic eyedrops to numb the eye and they put an IV in your arm with the "twilight sleep" anesthesia. They tie your arms to the gurney "so you won't try to help the doctor". The only unpleasant part is when the needle actually goes into your eye, but it's not painful, only shocking and wierd. They have some sort of frame over your face that lets them see inside your eye with a microscope (they dose your eye with dialation drops as well as anesthetic) and holds your eyelid open.
You don't see the needle coming towards your eye. I journaled about it; the link is in the comment you responded to. The needle goes through the white of the eye and they shoot ultrasound through it to turn the lens to mush, suck the mush out and insert the prosthetic lens. It sounds bad, but it isn't. The best part is I wore thick glasses all my life, I was severly myopic. The CrytaLens cures myopia (nearsightedness), presbyopia (farsightedness), astigmatism, and cataracts. The eye I have the implant in is now better than 20/20 at all distances, but the surgeon said mine worked out better than most.
Now, a vitrectomy [slashdot.org], that's a nightmare. I wouldn't wish one on anybody, but it sure beats the certainty of absolute blindness. BTW, one slashotter asked me to warn people before I link the vitrectomy journal, it really freaked him out. There's a link to the wikipedia article about victrectomy in that journal, and there's a picture in the wikipedia article that is NOT for the faint of heart. Pray you never have a detached retina!
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While I never had that problem (grow up in an ag area and you think nothing of picking rocks and sticks out of your eyes on a daily basis :) -- I think the trick may be to look in the mirror (I use a magnifying mirror like women use to apply cosmetics) and watch your finger, not your eye. Kinda makes it look like it's not *your* eye, which might be the trick for folks with a (fairly natural) phobia of stuff in their eyes. And then you don't actually SEE the finger coming at your eye, either.
I kinda like the progressive lenses (Score:3, Informative)
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?
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I really don't see what the big deal is. Can someone please explain why progressive lenses are so despised?
I like mine, but my mom can't get used to them. At all. They give her headaches and she just doesn't "get it", as you say. And she doesn't like bifocals much either.
She bought her 6th pair of glasses with progressive lenses about 2 weeks ago, because the optometrist told her it was a "new generation" of lenses for people who just couldn't get used to them. She paid a princely sum for them too. The resu
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The progressive lens I tried out at the optician's only gave clear focus over a five or ten degree horizontal field of view through most of its close-focus range. Anything left or right of center was astigmatically blurred. No way could I live with that, particularly in this day of "wider is better" displays.
I might consider a progressive lens that gave clear focus across the entire width of my FOV, but from what I've seen, that isn't happening.
Reading glasses! (Score:5, Interesting)
Reading glasses: $2 at Northern Tool. Regular prescription glasses: $40 from internet (china). Total cost: $42.
VS.
Trufocals: $895.
Next topic!
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Wow, if you get a cataract that's only a couple hundred bucks cheaper than having a Crystalens Implant (after insurance, which covers the cost of the old fashioned IOLs) and you don't have to wear glasses or use a slider, it focuses normally as if you were 20 years old with good vision. They'll implant them for myopia, presbyopia, and/or astigmatism as well but insurance won't cover it, the surgery is about $6,000 per eye. I have one in my left eye, my out of pocket cost was about a grand. Well worth every
1950 argument to that... (Score:2)
VS.
Trufocals: $895.
Next topic!
Cost of an electrical computer in 1954 : $400,000, not including the power cost for operation, the cost of either a new building to house it or several structural modifications, etc. And then there is highering a couple computers to check the equations going in, technicians to keep it operational, a supply of new tubes as they burn out... Why, you could be s
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.
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I'm 57 and I have no trouble at all with dexterity or manipulating tiny objects. The trouble most over 40s have with that is the fact that you get age related presbyopia (farsightedness) because your eye's focusing lens becomes hard, and it's pretty difficult to manipulate a small object you can't see.
I had one of my eyes fixed; I don't have presbyopia or myopia (I had both) any more.
Violates the KISS Principal (Score:3, Insightful)
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The problem this technology is intended to solve is the shortage of opticians in the remote impoverished villages of the world.
How soon can I get them? (Score:2)
If he's needs some beta testers I want to get on the list. I was prescribed bifocals a year and a half ago, kept them for a couple of months and had to give them up, I just couldn't find the comfort zone with them. So I'm back to single vision glasses, and while I have no problem reading or watching TV (for instance) I can't go back and forth between them. I'd buy this guy a beer if I could try his lenses on for a while.
Wait, what? (Score:2)
Now with these things, I'd have to constantly reach up to my face and adjust a little lever -- all day, every day.
That seems absurd.
Who Needs Bifocals? (Score:3, Funny)
Just get a bigger monitor.
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Just get a bigger monitor.
Just use a lower resolution.
A buddy of mine has a 42 inch LCD TV as his monitor and it gives me eyestrain whenever I read text on it.
I'm sorry (Score:2)
But I'll believe it when I see it.
I want this as a slip-on. (Score:2)
As glasses these will cost a bomb, and won't be covered by insurance for years.
As a lens slipped inside the glasses, they could be made more cheaply and sold OTC at Walgreens... and almost certainly end up making far more money by selling to a much larger market. And I'm sure they've got the patents locked up so nobody's going to be undercutting them with slip-ons.
If you click on the site... (Score:2)
You can see an Airplane pilot, adjusting his glasses to better see the control panel, which presumably means the pilot can't see inside and outside the plane at the same time.
Get me a ticket on that Airline!
Replace the lenses in the eyes! (Score:4, Interesting)
People get that way because the lenses in their eyes stiffen with age and soon the muscles int he eyes can't adjust them properly. People who have had certain type of cataract surgery where they replace the lens inside of the eye usually regain most all of their focusing ability.
Mod parent "only half-right"... (Score:4, Informative)
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.
Re:Replace the lenses in the eyes! (Score:4, Informative)
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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I knew my stiffening was going SOME place~
Do people just like wearing glasses? (Score:2)
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Outdated on invention! (Score:2)
Siemens created tiny lenses out of a drop of oil in a water suspension years ago. They work by the same principles, can be controlled with electrical fields, cost next to nothing, and are built into modern camera phones etc. This thing is just an upscaled version with a "lid". So one should be able to use electronic focusing on it too.
But it is not that new as a technology...
What about thermal effects? (Score:3, Interesting)
I guess I'll watch for this to hit the market, but am simply glad I don't need them yet.
absurd. (Score:2)
this enslaves you to the slider, instead of just shifting your head or your eyes to use a progressive lens.
must have an idiot cousin who has a factory to make little wedges that move lenses.
oh, by the way, prior art exists. see any camera lens. no patent forrrr YOU.
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Almost as absurd as your understanding of what is patentable.
It's NOT the idea, it's the implementation.
This is not new by any means (Score:2)
Yeah, well fro the last 20 years (Score:2)
growing new eyes has been the Holy Grail of eye care.
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There were only two people in the world who ever looked good in round glasses: John Lennon and Mahatma Gandhi.
This poor lady [trufocals.com] looks like she needs a wedgie.
The technology is very interesting, but you can't get any traction unless people are willing to actually buy and wear the glasses. As geeks, sometimes we overlook the attractiveness aspect of new technology. We shouldn't, it's half the battle.
ben franklin, doc hollywood.
the important thing is to purchase a scale proportional to your face (unlike this poor woman in the picture)
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You forgot Corporal Walter "RADAR" O'Reilly [wikimedia.org]
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Right, and that's why glasses never caught on in the first place until frame-makers started thinking 'fashion' and high-index lenses came around. Oh, wait...
Some people actually care about the functional aspect of the device. If these work well, I'd say they're likely to find a market.
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Because you don't want to walk around with huge glasses that goes Bzzz...Bzzzz... all day long, move your head around when the autofocus fails to reckon where the focal point is, and wear a battery-pack on your belt to power the thing.
Try using a manual-focus SLR camera for a day or two, and you'll realize your own autofocus (your brain) works way better than any piece of electronics.
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Laser eye surgery covers very small part of eye related problems.
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Yes, you're missing something. Laser surgery (LASIK) reshapes the cornea to adjust for the irregular shape of the eyeball. If your eye is too long you're nearsighted (and in danger of a detached retina) and too short you're farsighted. When you reach your forties the crystaline lens, the lens inside your eye behind the iris, becomes hard and won't focus.
See, your eye's focusing is so automatic that you don't even realize you're doing it until you reach middle age and can't do it any more.
If you're nearsight