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ToSeek
2005-Oct-24, 05:01 PM
Accidental Invention Points to End of Light Bulbs (http://www.livescience.com/technology/051021_nano_light.html)


The main light source of the future will almost surely not be a bulb. It might be a table, a wall, or even a fork.

An accidental discovery announced this week has taken LED lighting to a new level, suggesting it could soon offer a cheaper, longer-lasting alternative to the traditional light bulb. The miniature breakthrough adds to a growing trend that is likely to eventually make Thomas Edison's bright invention obsolete.

LEDs are already used in traffic lights, flashlights, and architectural lighting. They are flexible and operate less expensively than traditional lighting.

Glom
2005-Oct-24, 05:32 PM
The old order of incandescent light bulbs and cathode ray tubes is falling. Heating up elements is so last century.

WaxRubiks
2005-Oct-24, 05:50 PM
this can only go one way..

edit-:wink:

The Supreme Canuck
2005-Oct-24, 07:03 PM
I want to be able to buy LED lights for my home. Do you have any idea how much money that would save?

Just give it twenty years...

Swift
2005-Oct-24, 07:57 PM
That didn't seem to be a well written article. For example, they say

Quantum dots contain anywhere from 100 to 1,000 electrons. They're easily excited bundles of energy, and the smaller they are, the more excited they get. Each dot in Bower's particular batch was exceptionally small, containing only 33 or 34 pairs of atoms.
While the first sentence is true, I've never seen a quantum dot described by the number of electrons in it. I'm not sure what the second sentence even means - are the small bundles of energy the quantum dots or the electrons?

This (http://www.physorg.com/news7421.html) article from physorg.com is a little better - I was able to at least figure out the quantum dots are made from CdSe. It also seems to imply that, unlike the quote about "the smaller they are, the more excited they get", that the dots made of 33 or 34 molecules had a particularly favorable structure.

The particulars of this may be an "accident", but many research groups have been looking at the optical properties and fluorescence of quantum dots; here (http://www.llnl.gov/str/Lee.html) is a 1999 webpage from Lawreence Livermore Labs about them.

Swift
2005-Oct-24, 08:01 PM
I want to be able to buy LED lights for my home. Do you have any idea how much money that would save?

Just give it twenty years...
This (http://www.enluxled.com/) company is making them and seems to have a calculator to calculate your savings.

NEOWatcher
2005-Oct-24, 08:13 PM
This (http://www.enluxled.com/) company is making them and seems to have a calculator to calculate your savings.
For normal light around my house (of course virtually no labor to install) I got "Months until break even point: 87 months". Now I haven't priced light bulbs lately, but I think you can get them for less than $3. But even so, is my fixture going to last that long? If a break a bulb, I have to wait another 8 years for a pay-back.
This looks like it's ready for commercial applications, and I do applaud that, just not for your average shmoe.

WaxRubiks
2005-Oct-24, 08:16 PM
good for the environment too, it's not just the cost of the thing.

Swift
2005-Oct-24, 10:13 PM
For normal light around my house (of course virtually no labor to install) I got "Months until break even point: 87 months". Now I haven't priced light bulbs lately, but I think you can get them for less than $3. But even so, is my fixture going to last that long? If a break a bulb, I have to wait another 8 years for a pay-back.
This looks like it's ready for commercial applications, and I do applaud that, just not for your average shmoe.
I absolutely agree and that was my impression from the website; some of the numbers you had to input were labor costs to replace. For home use, compact fluorescents currently make much more sense. I suspect it will be years (5-10?) before the price of the LED lights comes down enough to be practical for residential use. And I'm not sure coating the lamp with CdSe quantum dot goop will drive the cost down - I think cheaper LEDs are the key. But LED lamps do exist now as devices.

RBG
2005-Oct-25, 06:12 AM
LED light bulbs are now going for sale in local big box hardware stores (up here in Canada). I don't know much at all about them other than I did a double take at its listed 1.5 Watts (!!)

RBG

Eroica
2005-Oct-25, 07:55 AM
Thomas Edison's bright invention
Sigh...

mugaliens
2007-Oct-31, 11:59 AM
For normal light around my house (of course virtually no labor to install) I got "Months until break even point: 87 months". Now I haven't priced light bulbs lately, but I think you can get them for less than $3. But even so, is my fixture going to last that long? If a break a bulb, I have to wait another 8 years for a pay-back.
This looks like it's ready for commercial applications, and I do applaud that, just not for your average shmoe.

The cost for a 100-lumen LED Edison screw-based bulb is now down to just $25, about twice that of it's flourescent equivalent, and still less than 10 times that of it's incandescent equivalent.

Just two years ago, it was four to five times the price of the flourescents.

It's been my experience that most household bulbs die between the 1.5 and 2 year point when used regularly.

For a per-year cost equivalent, that appears to mean that the LEDs should last between around 12 and 20 years.

Unfortunately, finance doesn't work that way, as you could be investing the difference ($22), right now, at 5%, which over just 12 years would yield a $17 profit. Of course there's the electricity savings, but that's a future income stream, not a lump sum we can invest at full value, now.

Where LEDs help is reduced cooling costs during the summer. Where they hurt is increased heating costs during the winter. For most climes, it averages out, but those living in, say, Texas, will gain more than those living in Seattle.

Why did I resurrect this? Because the prices have come down so much that for some, LEDs are starting to make sense, and this fact will only improve over time.

Meanwhile, the quantum dot progress marches on... Imagine - an entire cieling and four walls which simply turn on!

Talk about even lighting... But I've known people who've had spot lights which they'd position to reflect off many different wall and ceiling areas around the room. It created tons of indirect lighting, but I found that beyond a certain point, it's a little unnerving, like living inside a translucent gold-fish bowl.

I prefer a mixture of lighting styles around the room, each for it's own purpose.

Ivan Viehoff
2007-Oct-31, 12:18 PM
At present prices, the main use of LED lights in the home is for fittings that might be reached by inquisitive small children.

triplebird
2007-Oct-31, 12:59 PM
At present prices, the main use of LED lights in the home is for fittings that might be reached by inquisitive small children.

:confused:

In what way do you mean? If you're referring to the heat given off and said small child burning himself, CFLs work just as well as they're not hot to the touch compared to an incandescent. As far as breaking if the lamp is dropped, LEDs themselves are more durable, but the bulbs usually have electronics (as do CFLs) which are fragile.

JohnD
2007-Oct-31, 01:22 PM
The end of light bulbs?

Good question. Some say it's the metal end, as that where the current goes in, and out. Others prefer the rounded end ....

John

dgavin
2007-Oct-31, 01:51 PM
One good EMP blast from a Lighting Storm, and there go all your LED light bulbs.

While LED lights make sense i can think of that draw back, as well as the fact they haven't figured ot multi spectrum white LED's yet.

The latter would be useful in my arboretum during the winter months.

Ivan Viehoff
2007-Oct-31, 03:20 PM
In what way do you mean? If you're referring to the heat given off and said small child burning himself, CFLs work just as well as they're not hot to the touch compared to an incandescent. As far as breaking if the lamp is dropped, LEDs themselves are more durable, but the bulbs usually have electronics (as do CFLs) which are fragile.
It was the heat I had in mind, and I do know that CFLs are cool. But in some fittings CFL's burn themselves out. Also they don't work very well as spotlights/reading lights. In general one is recommended to use halogen bulbs instead of CFLs for these applications, but halogens are hot.

samkent
2007-Oct-31, 07:11 PM
The last time I check fluorescents were still more energy efficent than LEDs for the same light output.
In my home all of my lights are and have been for years, cfls or long tube fluorescent, except for two small base decorative lamps (8 watts ea).

Van Rijn
2007-Oct-31, 07:58 PM
While LED lights make sense i can think of that draw back, as well as the fact they haven't figured ot multi spectrum white LED's yet.


When CFLs first came out, one of the big problems was that their light was very harsh. Hopefully, they'll eventually be able to adjust the light output properly for these things.

By the way, I remember an article in Popular Science in the '70s (!) that predicted that white LEDs would eventually overtake regular lighting, and they predicted that it might go on walls, and so forth. They were just then starting to make LEDs with light output other than red, and there were efficiency and longevity problems.

Ronald Brak
2007-Nov-01, 08:45 AM
I wouldn't be surprised if in a year you could buy LED bulbs at a reasonable price low enough to make them worthwhile to many businesses.


One good EMP blast from a Lighting Storm, and there go all your LED light bulbs.

Are LEDs susceptable to lightning storms? I haven't noticed any problems with hand held LED torches.

Ken G
2007-Nov-03, 06:58 PM
The article says: The main light source of the future will almost surely not be a bulb. It might be a table, a wall, or even a fork.
I don't see this point at all-- it's not like the stuff glows on its own, you still have to excite it with other light. All it does is convert blue LED light to white LED light, which may be nice for aesthetics, but is hardly some new kind of source of light energy. How is this glowing fork supposed to work, exactly? I think you'll still see lamps, they'll just be more efficient and last longer.

Noclevername
2007-Nov-03, 07:03 PM
Whever anyone says "The _____ of the future will ______", you can usually wager money they'll be wrong. Historically, that statement has almost always turned out to be the kiss of death.

Tucson_Tim
2007-Nov-03, 07:24 PM
When CFLs first came out, one of the big problems was that their light was very harsh. Hopefully, they'll eventually be able to adjust the light output properly for these things.


The new ones are quite nice - warm light. We've replaced almost all our incandescent bulbs, even the overhead spots, with CFLs - a noticeable decrease in our electric bill. Plus the lesser heat produced is great here in the SW. Only drawback we've seen is that they take 30 sec to 1 min to fully brighten - not a real problem for us.

ETA: For the spot lights, the CFLs can be purchased in any color, from cold to warm.

BUT: The cats don't like them as much now that cooler temps are here . . . :)

neilzero
2007-Nov-03, 10:29 PM
We have a small Christmas tree with about 90 red LED lights (All in series I suspect) that have been connected to 120 volts ac during numerous near by lightening strikes. All are still lit. That may not indicate insensitive to EMP as they likely receive less than 1/10 th watt each, while newer light are typically operated at the edge of disaster. Hopefully the new brighter LEDs are surge protected. Neil

dgavin
2007-Nov-03, 10:48 PM
I wouldn't be surprised if in a year you could buy LED bulbs at a reasonable price low enough to make them worthwhile to many businesses.



Are LEDs susceptable to lightning storms? I haven't noticed any problems with hand held LED torches.

Most IC's, Transitors. However as LED's are a diode, perhaps a rectifier is safe from EMP disruption. I'm assuming mose micro electric devices have isses with EMP.

I think Diode's are natualy resistant to Surge damage, again because they only allow for a one way flow of current.

dgavin
2007-Nov-04, 08:46 PM
Perhaps i spoke too soon about White LED's.

I just picked up a string of rather bright LED Xmas lights. With all colors, including White (not bright blue/white)

GE is the manufacturer