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Nanotech Coating Prevents Fogging
MilSF1 writes "MIT scientists have applied for a patent on a coating process that reduces or eliminates fogging on glass surfaces (car windshields, eyeglasses, etc). The new coating was described today at the 230th national meeting of the American Chemical Society."
I, for one, don't have glass lenses. Normally, that's a good thing, as it keeps me from getting shards in my eyes as much, but now I'm not so sure.
Note to mods: I'm probably being sarcastic.
Ever wanted a shave in the shower but your hand-held mirror fogs up? Rather than buying this patented glass you can resort to a low-tech solution: Rub a little shaving foam over the glass and the wash the excess off so you have a thin, clear, greasy film on the glass.You'll find that the mirror no longer steams up.
The reason this works is because the greasy film causes much larger drops to coalesce on the mirror than you would normally get. These larger drops don't refract the light nearly and as a result are essentially transparent. This simple trick allows me to insure my sideburns are the same length even when under the most horrendous time presure.
See, who says that Physics can't be useful in everyday situations?
Simon
XP + Nanotech coating = Transparent Windows! Probly explains the long delay in releasing LongHorn...
If you keep throwing chairs, one day you'll break windows....
Develop a coating for glasses that prevents greasy smudging from eating chips and other junk food. The anti-fogging stuff sounds OK for a nasal spray straight to the brain on those mornings after.
And want a cheaper solution for keeping your bathroom mirror fog free, before you get in the shower/bath/whatever, rub some shaving foam into the glass. not alot - about a cm^2 blob. then rub with a very damp cloth so it dissapears and u can see your reflection.
Have the shower!
Get out, go to shave, and voila! No foggy window!
This nanotech gaff will definately work wonders in the car. Hey, it will mean I wont have to bust my gut when I get in having to clean every window of fog while my gf drives. now that I mention it, I should really learn to drive...
I won't believe any of this until there is a Podcast released on it.
The people who make rain-x, which works rather well itself to deflect rain, also make fog-x, which I've tested on a steamy bathroom mirror, and it works perfectly.
Who do they think they're foolin'?
More light than comes from through the glass??
if it makes a smoother surface, it could allow more light through
MIT scientists have applied for a patent on a coating process that reduces or eliminates fogging on glass surfaces. The new coating consists of a highly acidic chemical that melts the glass into a thick green goo. While the glass (now known as green goo) possesses none of its original qualities including transparency, it has also been shown to provide a 5% or greater resistance to fog.
I'm a big tall mofo.
The transparent coating can be applied to eyeglasses, camera lenses, ski goggles ... even bathroom mirrors, they say
It seems clear to me that this thingie is applied on existing surfaces.
Therefore applied on glass.
Now can one explain, if the glass allows X% of light to pass, how can this "coating" amplify it to X+?
And no, I'm not trolling.
gtkaml.org
I wonder if it can be applied to motherboard, if you plan using liquid nitrogen, dry ice or such for cooling :) Air humidity condensation on nearby elements is one of the worst problems with high-efficiency CPU cooling.
Anagram("United States of America") == "Dine out, taste a Mac, fries"
...they simply spit in their masks to prevent fogging.
Fogging of glasses is a problem. The visor problem's been largely solved what with Foggy Masks, Fog City films but it's still a problem for those who wear glasses.
Deleted
One of the worst things about wearing glasses up north is the fogging.. being outside in -25c temperatures for even a few minutes and glasses get cold enough that they fog up when paying for gas, or shovelling snow, etc.. pain in the ass. I welcome this new technology :)
May be this will finally replace the old method of spit and rinse, because all those special glasses on the scuba masks had no effect until now. For those who don't know, if you want your scuba mask to be perfectly clean of fog, you have to spit inside it when it is dry, then rinse very fast with sea water (just to make the glass clear enough but probably without rinsing all the substances in the saliva from the glass) then put it on the face and dive immediately. For those who forgot doing this, even the best tempered glass became foggy in a few minutes in cold water.
"My crew chief applied a coating of Drene Shampoo to the windshield. For some unknown reason it worked as an effective antifrost device, and we continued using it even after the government purchased a special chemical that cost eighteen bucks a bottle."
Basically, they take a glass/plastic mix of microscopic particles, coat the glass and then subject it to high heat, making a glass sponge (Very simplified explination).
I always think of nanotech as something more novel. If this were thousands of billions of tiny squeegee bulldozers one micron across moving the water to the edge of the glass, then I'd consider it nanotech.
The simple truth is that interstellar distances will not fit into the human imagination
- Douglas Adams
Motor helmet screens come with this kind of anti-fog layer for several years already, see for example: http://www.bellmotorsports.com/helacc.shtml or http://ecom1.sno-ski.net/goggles.html for fog free goggles. So did MIT do their background research before starting this patents application?
My wife's sketchblog Blob[p]: Gastrono-me
Because most of the light that does not pass through the glass is not "absorbed" inside the the glass but instead reflected at the air/glass and glass/air boundary layers.
Coating glass with stuff to minimize the reflection is a really old thing. Ever wonder why the lenses of (good) binoculars seem have a bluish or reddish tint to them ? Because they're coated to increase light transmission.
Does it work for any kind of smoke?
lick your mirror. you'll find it wont fog for a while after that.
Their claim is valid. Anytime light passes through an abrupt change in the index of refraction (e.g., from air to glass), a percentage of the light it reflected back. That's why you see a ghost image of yourself in even "transparent" pieces of glass. On ordinary glass, about 4% of the light is reflected (removed) by each air-to-glass or glass-to-air interface (8% for each pane).
Adding a anti-reflective coating that has an intermediate index of refraction can reduce this. Nonlinearities in the reflection process mean that two interfaces of lesser change reflect far less than one big change. Camera lens makers do this all the time because many lens have 6 to 20 pieces of glass and thus a dozen or more interfaces that each would to attenuate light and create multiple internal reflections between the lens elements.
It may not be much, but that antifog coating probably lets a couple extra percent of the light through.
Two wrongs don't make a right, but three lefts do.
I have glasses and I have tried everything to keep the darned things from fogging up in the winter when I am outside.
:)
It's ANNOYING.
I'd like to beta test this stuff... I wonder if they'd send me a batch.
'Twixt Light and Darkness... S S H A D O W
I'm not a raging anti-patent looney screaming about the need for a free utopioan society, but if funding for this was provided by the public, surely the results belong to the public and the methods belong in the public domain rather than to MIT for the next 17-34 years.
woof.
Blind people need glasses too! X-D
Karma: It's all a bunch of tree-huggin' hippy crap!
Applying a patent for a sponge just doesn't sound good enough. And hey, maybe later they can extend the explanation of the patent to include the standard sponges used to wash your windows.
You pay MIT every time you buy a sponge!
My wife's sketchblog Blob[p]: Gastrono-me
-William Brendel
Just the other week I was nearly driven crazy by a layer of fog that had snuck in-between the two lenses of my ski goggles. It took several days of sitting them next to a heater before the problem was fixed. Presumably this couldn't happen with totally fog-free lenses.
Easy. Regular glass surface in air reflects back about 4% of the incoming light. Reduce this to 1% and you'll get 3% more light through. That is why most optics is coated.
Since the silica coating will prevent water droplets from condensing on glass wouldn't that also prevent frost from freezing on a windshield? Of course that would require coating the outside of the windshield.
01/20/09
Neither do I. Mine are plastic and they're mounted inside my eyeballs! I also have a totally artificial metal tooth bolted into my jawbone. All I'm missing is a bolt protruding from my neck to complete my bionic image. ;-)
P.S. I had cataract surgery with lens replacement in both eyes a few years ago probably because of long term cortisone use.
9/11 Eyewitnesses to Explosive WTC Demolition 1 of 2
I look forward for swimming glasses which do
not fog up. They usually do, evenso the packages
claim they have a coating which should prevent that. When swimming competitively, we had a low-tech solution: spit on the inside of the goggles would prevent fogging up.
I don't know why they're bandying the term "nanotechnology" around, because it's not. It's a silica coating that prevents fogging. In fact, the only reason this made it to slashdot is because the term "nanotechnology" was used in the title of the original press release. You'd think the people at MIT and the ACS would know better.
This does not meet those criteria.
What is humor if not pain tempered by time?
I am pretty much ready to sell my soul to get a windshield with that treatment, trying to drive a volvo 745 with a crappy heater is downright dangerous when you can't see worth s*** and the roads are slippery.
From the article: "The new coating prevents this process from occurring, primarily through its super-hydrophilic, or water-loving, nature [...]"
I recall this being one of the properties of nano-coated self-cleaning glass such as Pilkington Activ or PPG SunClean, so does that not already provide the same anti-fog advantages?
The explanation is not quite right.
Antireflection coatings have a thickness of 1/4 lambda so that half the light that would normally be reflected is reflected with 180degrees phase shift. Thus for a single wavelength (v-Coating) it is possible to reduce reflection from 4% to less than 0.1%. For a broader range of wavelengths (U-coating) a number of coatings of different thicknesses are used.
The coating itself (typically CaF) is chosen because it is relatively easy to vapour-deposit to controlled thickness and because its refractive index is halfway between that of air and glass.
Somehow I don't believe that the same effect could be achieved by a thin film of water, though it's probably better than nothing.
Too late! Quatro razors already come with a non-fog mirror. Works, too.
And if you wish for a slightly higher tech solution, your local auto parts store sells a product called Fog-X which when applied to glass, prevents fogging.
Just use soap, works better and is cheaper than shaving foam.
The explanation is not quite right.
Antireflection coatings have a thickness of 1/4 lambda so that half the light that would normally be reflected is reflected with 180degrees phase shift. Thus for a single wavelength (v-Coating) it is possible to reduce reflection from 4% to less than 0.1%. For a broader range of wavelengths (U-coating) a number of coatings of different thicknesses are used.
Yes, a 1/4 lambda film maximizes antireflection but a thicker film also works -- reducing reflection from 4% to 2%.
The coating itself (typically CaF) is chosen because it is relatively easy to vapour-deposit to controlled thickness and because its refractive index is halfway between that of air and glass.
Actually CaF2 doesn't have a very good index (1.44). MgF2 is a bit better at 1.38. Neither are half-way for normal glass, but they do work well with higher index glasses.
Somehow I don't believe that the same effect could be achieved by a thin film of water, though it's probably better than nothing.
Water's index of 1.33 makes it better than MgF2 or CaF2 as an anti-reflective coating. I'm not sure how the anti-fog coating changes the index, though.
Two wrongs don't make a right, but three lefts do.
Fogging ski goggles is a real safety issue. Your breath always manages to get up into them, especially if you are wearing a face mask.
When I was climbing Mt Rainier I had to wear goggles on the last half due to strong winds and I was practically blind from the iced up fog. No attempts to rewarm them in my jacket worked, it was a real pain. Same thing happens on winter climbs in the Presidentials in NH. I've even tried applied coatings like "cat crap" but they don't work.
A coating that works on plastic that can stop icing as well as fogging would be a major safety enhancement.
It is by the juice of the coffee bean that thoughts acquire speed, the teeth acquire stains. The stains become a warning
... have applied for a patent...
Which means I'll be old and gray before I ever wear a pair of glasses with this stuff or own a car that has a windshield with it -- even if it's a potentially cheap solution.
An engineer named Richard Hartman developed antifog glasses for whitewater kayaking based on this concept several years ago. He developed a hydrophillic coating that was baked onto the lenses, and which prevented the formation of fog droplets. He even offered them for sale for a time--send him your prescription and he would send back a pair of glasses. I don't think he does that anymore.
Here is a recent post describing his work.
Here is a post from 2001 answering some questions about the glasses.
Here is a search on the Boatertalk forum for most posts about it.
Build a man a fire, he's warm for one night. Set him on fire, and he's warm for the rest of his life.
"Glass containing titanium dioxide also shows promise for reduced fogging, but the method only works in the presence of ultraviolet (UV) light, researchers say." Surely if there's no light then whether the glass is fogged up or not is irrelevant. Ok Ok so it says UV light... which we have loads of now the ozone is dwindling :)
Try toothpaste. Rub it on, wash it off. It may not last forever, but it does prevent fogging and its a lot cheaper. The only drawback is it would take a lot of it for a windshield.
Speaking as an MIT student working on this project, yes it lets more light through- a lot. Uncoated silica reflects about 8% of incident light, as was posted elsewhere. With our coating, this drops below one percent through most of the visible spectrum, and below .2% at a peak wavelength dependent on the number of coating layers (around 550nm for a 14-bilayer coating). It's a pretty nice improvement- you can place a half-coated slide against white paper and the untreated side looks dirty by comparison. I can try to dig up the spectrophotometer measurements I took a few weeks ago, if anyone cares that much.
/.ed. Party in lab today!
Also: Whoa, Rubner got
http://www.cyclegadgets.com/Products/product.asp?I tem=FC
These things are sweet. They don't fog, period, and if you get the UV reactive one, it darkens in sunlight so you don't need to carry two shields. It's not quite as dark a real reflective shield, but it's dark enough.
The president of the Drive-in Movie Enthusiast Organization was left speechless.
Congrats. How large are the nanoparticles? Do you make them in-house or buy them? I assume they are assembled using an LbL technique? jhw3 Swager group alumnus
I have a product called FogX that I've been putting on the inside of my car windshield for years. No fog, no hassle, low cost. I've also been applying it to bathroom mirrors and such. Am I completely missing something, or is this not exactly a breakthrough?
This is great news for slashdotters. Now when you're making out with your girlfriend in the backseat of the car ... oh, wait. Never mind!
10nm gives the best results I've been able to get. Silica particles are much more convenient to buy, though we did end up making a huge batch of titania since the shipping from Japan was being slow. And yeah, the coatings are applied LbL with what's basically an expensive fancy spinning version of a slide stainer. I can't back it up with tons of evidence yet, but the spinning action seems to make it much easier to get a nice even coating.
Apply this to little Timmy's car windows so he can no longer fog up the windows and hide the goings on in parked car. At the very least, could be more amusing for passers-by.
We just called this "chemistry."
I think CmdrTaco had a story about a windshield-wiper hack for motorcycle helmets. All you need is an electrode, a blade, and a blue LED.
Years ago, I read that some Japanese (company) had a very smart solution: Don't make the surface very hydrophobic, but very hydrophilic. No individual droplets will form, but rather a film of water is formed providing near perfect vision (hm, sorry, this foreigner has problems formulating this).
Didn't hear much about it later, though.
Bert
What I finally found that works for me is toothpaste. I always take a tube and just smear a little bit all around and rinse out. The best cheapest anti fog anywhere. Some people will tell you that the grit is bad for the lenses. That may be true but mine is still very clear over several years of use.
TODO create witty sig.
My girlfriends father works for AFG glass industries and he supposedly already did this and has the patent? Maybe I just dont understand the particulars but they've already started production of fog-less glass and are shipping the product next week.
Why is it that every time any dope at MIT creates or invents some invention, we all have to hear about it. I am sure if it was invented at University of Southwestern South Dakota A & M, we would never have heard of the damn thing. I know MIT has a lot of smart people, but for godsakes we are talking about fogging of glass. This is not Nobel Prize work. P.S.--Yes I am bitter those assholes rejected me from their Phd program.
When I was a kid, snake-oil salesmen at county fairs sold "no fog" spray for mirrors.
It worked. Sort of.
I once bought a mirror that came "fog free" from the factory and when I tried to clean it, the result was like if I put vaseline on it. Ewwww.
My captcha is "polish." No joke.
Nice work. Now can you make something that will shock the hell out of my cube mate when she puts her greasy fingers all over my laptop screen? I'm thinking something along the lines of a cross between a cattle prod and a taser. Maybe throw in a paintball gun for good measure.
Would this work as a anti-dew coating on a telescope?
It would be nice to rid my set up of dew heaters and the attendant cables and power needs.
SteveM
I race triathlons. When you're swimming in 55-degree ocean water, but your eyes are at body temperature, the goggles fog so badly that it can become next-to-impossible to see the damn buoy you're aiming for. And the last thing you want is to be lost, swimming a zigzag and adding 35% to your distance.
I stole this sig from someone cleverer than me.
I submit that an appropriate domain for the term "nanotechnology" is something more in line with Eric K. Drexler's ("Engines of Creation" is a great layman's read!) work: sub-micron scale machines. To clarify: "In physics, a simple machine is any device that only requires the application of a single force to work" ( http://en.wikipedia.org/wiki/Simple_machine ). Perhaps such a definition would need some small modification as atomic forces factor in much more prominently at the nano-level, yet I think it is a solid starting point.
It clearly follows that the technology cited in this article, while noble, novel and useful, is not nanotech, as it is not machinery, at least not by this initial suggested definition.
It amazes me that this kind of thing slips by the slashdo[tt] editors regularly. Bad science masquerading as legitimate theory. But I really don't see how nanoparticles are going to prevent people from getting flogged. On the one hand you've got a bunch of inanimate particles on the nano level and on the other hand you've got a guy in an executioner's hood holding a cat-o-nine tails above you. What possible match is there? The guy in the executioner's hood is going to win every time. Trust me. I know from experience, I went to catholic school fer crissakes! So... oh? What? Ohhhh... "fogging" not "flogging". Oh. Sorry for the mix up. Oh geez. Now I feel silly. I think I'm gonna blush... Bye. ;P
-"...bad old ideas look confusingly fresh when they are packaged as technology" - Jaron Lanier (Digital Maoism on Edge.o
I had no idea that /. could actually report on worthwhile patents! On a more serious note, this really is worthy of a patent, and it's pretty cool. I'd like such a windshield down here in humid Georgia.
I am Spartacus
Firemen and HAZMAT workers have to open a 'de-fogging' vent on their SCBA's to dissipate fog from their facemasks, wasting air. This coating could add minutes to a workers time on scene.
Already installed in my car (a 1994 model), and requiring no re-application or chemicals, no electricity, and once activated it stays activated until manually deactivated. Even in a deactivated state this amazing invention provides an invisible barrier to dangerous atmospheric gas -- such as carbondioxide and powerful solvents such as dihydrogenmonoxide often found in highly toxic acid rain.
This device is designed with macro technology (buzzword: MacroTech) -- which is not plagued by the extremely dangerous problems associated with nano techology.
What is this incredible device? It's called a drivers side window. Once "opened" 3" to 4", my windshield is not only cleared of any fog, but it says clear until the device is "closed" again!
Required reading for internet skeptics
Don't forget all of the wonderful applications this could serve in the field of paintball! I hate when my goggles fog up and people shoot me :0
~@~
It seems to me that people have all kinds of solutions to keep surfaces from fogging or to make the water that does condense on the surface to remain clear. However there are two things that seem to be difficult to do with any of these solutions.
They are to make the solution permanent and durable and...
To make the solution of a material that will not distort your vision when looking through the surface of the material.
So yes, you could apply rain-X every month or wipe shaving cream on your surface or even make sure the surface is vented or heat the surface. However having a permanent coating on it that prevents fogging and makes it easy to see through is the best solution.
Wow, I've never driven with un-fogged beer gogs before. This is going to be great!!
Join the Slashcott! Feb 10 thru Feb 17!
And how many newbie divers have you gotten to spit on themselves with that one?
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?