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LED Guru On InGaN-Based LEDs And The Future
Mayor Quimby writes: "EETimes reports that LED guru Shuji Nakamura predicts
White LEDs to overtake the light bulb
Mr. Nakamura is an amazing guy who is given substantial credit in the
development of blue and white LEDs. Other articles about him can be found
here and
here.
He "works from 7 a.m. to 7 p.m., 355 days a year, and says he has never taken a vacation." Also, check out this circuit board
found in an LED flashlight that uses a single AA battery. It'll be nice when low cost knockoffs start flooding in from the Far East." I can vouch for the life of white-LED flashlights -- the ones I purchased more than a year ago from Holly Solar are still on their first sets of AA batteries. Not as bright as incandescents, but plenty for lighting up a tent or to keep from stumbling on a trail.
Back in MY day, we worked all 365 days of the year.
- I don't care if they globalize against free speech. All my best free thoughts are done in my head.
Does this mean we will have *super* photon lights in the future?
If you combined this with a transmeta chip, the power savings would be enormous!! If one of those regenerative keyboards was thrown into the mix, these things would last forever.
LED lights certainly have their places. I own a Petzl Tikka headlamp that runs off three AAA batteries. I use this headlamp (along with a Princeton Tec Quest and a premier carbide lamp) for the caving i do here in the Northeast (specifically around the Albany NY area).
Anyway, the LED lamp uses three white LED's and doesn't put off anywhere near the light of the 2-AA princeton tec with a standard bulb. However, by way of comparison, it produces a more disperse light and it will last up to 150 hours on a single set of batteries, compared with 6-8 on the Princeton Tec.
The light is certainly whiter than most anything but maybe a xenon bulb (which uses tons of power). It has virtually no range, though. It lights up a nice hemisphere in front of me for a good 6 feet whereas the carbide and Princeton Tec can send a light several dozen.
I keep thinking that if they made a headlamp that had so many LED's in it that it sucked as much power as the standard bulb, it would be fucking bright indeed.....
Oh yeah, and the Tikka was almost $40 and the Quest was $15.
Did you ever realize there were no laptop computers before LEDs were invented? That's no coincidence. The little green-power-is-on incandescent light sucked too much power and made laptops a worthless concept. Thank LEDs for solving that bottleneck!
Yup, and 'round about these parts (San Francisco peninsula), they're starting to retrofit the green traffic lights as well, and man that shade of green is gorgeous to behold...
Schwab
Editor, A1-AAA AmeriCaptions
Lovely LED's letting luscious luminence lift lonely lives. Light leaves love's lost luminairies lamenting, languishing, listlessly listening lest loveless labor limit life.
Lo! Love leverages light. Light limits love. Love learns light lessens lucidity. Loss lies lurking, luring lovers 'long looping lanes lacking love, leaving little. Less. Lust.
-Intense introspection
-Into interesting interpretations
-Involving intellectual indulgences
Any one have any info about the range of light they put out?
Cuz I was thinking, no heat and low power, these would make good grow lamps . . .
Fire Jon Katz. Hire Neal Stephenson. (make this your sig too)
LED museum
All Rights Reversed.
I was thinking of how household lighting might be implemented with white LED's---
I guess you'd need a lot more LED's (or banks of them) then bulbs. Since LED's are also DC beasts, you'd need to convert to DC with a rectifier circuit from the standard 110 VAC. I guess this would be best done once (instead of having a rectifier at each lighting location), and seperate 5 V (or 12 V or whatever) circuits for lighting only done throughout a house. This would be best applied to new houses only. Having a seperate rectifier at each light location (i.e. to replace traditional bulbs) would probably be wasteful and expensive.
So why haven't floresent light taken over?
The light from floresent lamps is, emotionally speaking, "cold" and "unpleasant". I have an Inova light (a cheap clone of the photon light), and the light from it by itself is cold and harsh compared to tungsten lights.
- Sam
The secret to enjoying Slashdot is to realize that it should not be taken too seriously.
The real place for the white, or colored LEDs is in locations where replacing the light is a pain in the *ss. Think about it. If you need to replace a traffic light, you need to turn off the light, put a cop there, and drag out the truck and the guys to replace the bulb. Instead of incandescent, by using LEDs you can have replacements every 5+ years (because you'll have 40+ LED's and a few burned out ones won't be a problem). This makes perfect sense, and makes the added cost of the LEDs an excellent investment. (trust me, traffic cops on overtime make way more for the hour plus it takes to replace a bulb than the cost of 50 green LEDs.) This is why in the Bay Area, almost all red lights are already LEDs, and more and more yellows and greens are being changed.
Similarly, think about lights in places where they are difficult to replace. Embedded lights in offices come to mind. Anywhere were work has to stop to replace a light, it makes sense to pay $30 for a bulb. In the home, on the other hand, the cost of replacement is negligible. So, LEDs probably won't take over until they are almost as cheap as standard bulbs. On the other hand, I'd love to replace the pool lights with LEDs, because I have to lower the water level, which is a complete pain, to replace those lights.
Thalia
If you don't have a LED light, go get one - it's compact, durable, extremely bright, and battery life is awesome. Quite enjoyable! I personally love the Photon II, but be sure to read Brock's LED Flashlight Page first, before buying a dud like the NightHawk, which is not bright at all.
Now that I'm done with links - I'll say this - while LED lights are great for directional lighting, they are not good at all for omni-directional lighting. This is because the reflector is housed inside the LED itself, and the light will always be facing the direction of the LED plate.
Now... I wonder how difficult it would be to get that LED plate inside the plastic/resin housing into a shape of a cylinder, and install it in place of a standard tungsten filament? If that is possible, then the LED light will truly be able to replace all lightbulbs... Not just the directional ones.
Hmm, I guess I don't have much to say other than the good links up top, and my hope for tomorrow's LED, household lightbulb. If you experts have something to say about the possibility of the cylindrical LED plate, I'm all ears. I surely don't know if it's possible or not.
"It'll be nice when low cost knockoffs start flooding in from the Far East."
Why? Because the product you end up with will be flimsy? Because you'll have to return the first three before finding one that works? Because the company that developed this product will stop receiving any return on their R&D? Because your Uncle is some slave-labor king in Malaysia? You sure won't be "vouching for the life" of any low-cost knockoff.
If you think about the success of the MAG light, you will realize that low-cost knockoffs probably wouldn't even be attractive to most people.
The Infinity task light linked to is a good little light. If I could only have one LED light it would be the Photon Micro Light, but the Infinity is still a good option if you don't want to use button cells. It could benefit from some reflective material around the LED perhaps, as the light output is much less than the Photon. Maybe I'll polish the metal around the LED... hmmm.
>> over his blue chip to get a white light."
Is this really a white "LED"? Sounds like a blue
led activating phosphorous to me, which hardly
seems would be the holy grail.
Don't get me wrong, it's great about Nakamura
developing the blue led, I just don't think we
should call this a white "LED".
Of course, these were very popular among certain folks who were stocking up for the Y2K crisis last year. (Everyone who remembers the end of Western Civilization, raise your hands).
Actually not a bad technology, but a little pricey if you do not have a real need for it.
C. Crane company has some cool things, although they are more oriented towards the radio geeks
"It is a greater offense to steal men's labor, than their clothes"
a friend of mine works at a top notch NYC lighting design firm. When I sent him the EE Times article, he replied: "LED can be electronically dimmed and when in an array for red, blue and green LEDs, you can simulate full spectrum color mixing. The low-tech way to do a seamlessly color changing lightbox, for example, would be to use dimmable fluorescent with color sleeves or three colors of neon." "If you find yourself at the Shoreham Hotel Bar, or Stueben Glass Showroom, you will see some of our work. The only problem with LED is that is prohibitively expensive. There were only a handful of quality LED suppliers 2 years ago. I'm glad it's catching on though, hopefully prices will go down." "Neon is $30/ linear foot installed in NYC. Raw LED strips can cost a minimum of $150/ft. sans necessary programming and playback devices." "Colorcorp and Color Kinetics are doing some interesting display lighting with LED."
I think the proponents of LED lighting linked above may have streached a little when they state:
A standard incandescent bulb will typically burn out in less than 40 hours.
That sees a little bit low to me... unless you mean 'standard' being the homemade lightbulb created with a vacuum pump and a piece of yarn.
Ah, but with the ability to make red, green, blue, yellow, and white LEDs, couldn't the combined light produced be tuned to emulate natural light?
-Nev
No, because the spectrum of sunlight is continuous, so you would need an infinite number of LED's at wavelengths between 400 and 700 nm.
From 7 am to 7 pm, 355 days a year and no vacation? What's so big on this. Does this makes his LEDs better? I know LOTS of people, in well known "lazy" Russia working 12-16 hours a day. From 10 am to 11 pm, 1pm to 4am, 7pm to 7am. Or like "dusk to dawn" (HEY we are not vampires! It's just no one BOTHERS you). And many work one, two, three years without vacations, on holidays and Sundays. On the screen I am seeing the reflection of one guy with 6 years work in a row (oh daaaaamn! Yeap, need vacation!..)
Yeah fellow Japanese and Chinese are traditional workaholists. But frankly I believe that our fellow americans and europeans have also such epidemy catching their lifes... At least some friends say things like "sorry I'm in the 14th hour, going to sleep". So I don't think that workaholism will made his LEDs shine brighter...
LED's are terrific. Increased reliability, higher efficiency, lower power consumption, higher peak output, and better heat dissipation.
BUT, one 'negative' side effect of greater LED usage is the NTSB will have less forensic evidence after aircrashes (at least with smaller private planes without a flight data recorder)...
At moment-of-impact, the filament from a lit bulb breaks apart differently from an already-burned out bulb or from an operable-but-not-lit bulb.
Here's an article that describes filament analysis. And two reports, one where LED's prevent filament analysis (search for "filament analysis") and another where analysis showed the status of indicators (search for "filament stretching")
Slightly off-topic, but interesting, I think.
An infinite number of LED's at wavelengths between 400 and 700 nm is not required to emulate sunlight for humans. How do you think TV, film, and printing work? Humans have only 3 separate color sensors and therefore the earlier poster is correct, a sunlight color could be achieved with 3 LED's. However, this is not how most white LED's work anyway (read the recent Technology Review article for explanations), and the white LED's I've seen have more blue content than sunlight. For flashlight applications, I've found this to be acceptable and perhaps even preferable.
LED's are not going to do well in home lighting for quite some time if ever. Fluorescent lighting is more efficient, reasonably color balanced, and much much cheaper per lumen output.
He "works from 7 a.m. to 7 p.m., 355 days a year, and says he has never taken a vacation."
And this is supposed to be a good thing? Obsessing about anything to the verge of lunacy, and sacrificing all the other things that really make life worth living, is hardly a healthy way to live. The quality of life on this planet is only going to get worse as long as people keep praising this kind of unreasonable work ethic.
- "It's just a matter of opinion!" - PRIMUS
Hey, I love LEDs as much as the next geek, and I believe they could take over regular lighting (for a long time I wondered why they were only used on the third brake light, and nowhere else, then the turn signal and brake lights for commercial vehicles came on the market, and now one of the Cadillacs have them - should trickle down to regular vehicles soon). Still, I think there is another option not too many people know about:
Tesla bulbs.
These bulbs work in a similar fashion as a flourescent bulb. Essentially, the bulb looks like a normal bulb, but with a wire running up the middle in a glass tube, tipped with a small metal sphere. The inside of the bulb is "coated" with a material that flouresces in the presense of intense radio waves. When Tesla was experimenting with them, simply holding one in the presence of a Tesla coil was enough to get them to light, but they were really meant to be "directly" connected to the Tesla coil output.
IIRC, Tesla's original bulbs weren't very bright, but they showed the concept well. Later inventors have experimented with the system, and built bulbs in which the Tesla coil formed part of the "filament", with some of the electronics in the base of the bulb - meant to be screwed into an ordinary socket and run off of normal houshold current. These bulbs were much brighter, and supposedly last for over 50 years of continuous operation.
I don't know if they were ever manufactured on a large scale. They were VERY expensive, supposedly costing over $30 each, but given their longevity over ordinary bulbs, this wasn't a real issue. They were meant for commercial installations, where changing a bulb was difficult or dangerous.
Does anyone know more about these bulbs, and whether they still exist (I tend to wonder if the new compact flourecents have taken over)?
Worldcom - Generation Duh!
Reason is the Path to God - Anon
This won't be the first time that the Japenese help the White LED (the third letter stands for death). I seem to remember a little incident called World War II.
I think the Japanese got to see more than enough white light during WWII. Maybe that served as the inspiration for the white LED?
Around here, most Jews seem to drive German cars; most Chinese people seem to be driving Japanese cars.
Personally, while I wouldn't touch a Japanese car with a ten meter cattleprod, but speaking as a former tech at a TV station, no one has ever made a better TV set than Sony. As long as the Japanese allow North American manufacturers to sell their products there, I have no problem with the Japanese selling their products here. Competition and innovation are mutually beneficial.
Forgiveness is an interesting thing. And a good thing.
Fire and Meat. Yummy.
Am I crazy, or does that have implications for long-term space flight?
You're probably crazy, but yes, it does.
Fluorescent lights are not as efficient as LEDs, though they're still more practical for the moment. And they're bulky, the ballasts are heavy, and they're fragile. The LED will first see general lighting use in space, but I don't think it's ready for that yet.
And yes, it's another one of those evolutionary improvements that will improve the technology of space travel. I'm still holding out for the revolutionary ones, like superluminal travel and gravity manipulation.
Fire and Meat. Yummy.
Actually LED screens would be pretty sweet, if they could build them pixel-sized. They're bright, don't require crazy voltage like back-lights do, refresh super fast, black blacks and white whites....
White LEDs are already being adopted as replacements for the fluorescent tubes or electroluminescent sheets being used as notebook backlights. You can now get large (notebook display sized) sheets of frosted white plastic with white LED junctions embedded for use as backlighting in new notebooks. It will basically work like an electroluminescent backlight but without the inefficient and failure-prone inverter. I saw them advertised in an electronics engineering trade magazine that I get.
Fire and Meat. Yummy.
I have always preferred Light Emitting EPROMs, though they're a lot more expensive and don't last as long. (plug one into your breadboard backwards)
Or try programming it on the wrong voltage. (Ooops.)
Fire and Meat. Yummy.
Hondas today are high-quality, low-maintenance, reasonable price -- a net customer benefit.
Sure. Disposable and expendable, like their owners.
Fire and Meat. Yummy.
So that's my car. It's messy right now, need to clean it and would if it weren't raining here. It's not flashy, but the tape deck works and I have a nubby cover on the steering wheel
Listen, I'm not a Saab fan, and I'm not an Escort fan. Neither is a car that I like.
But to compare the reliability of a 14 year old turbocharged luxury car against a 5 year old econobox is patently unfair.
Because of its age, it's probable that the Saab had more miles on it. It's also probable that the Saab, being a turbocharged alleged sports car was also driven harder. It's a luxury car, too - more complicated, with more things to break or wear out.
And, it's definite that because the car was nine years older than the Escort, there was a lot of decay to little things that nickel-and-dime you to death unless you know how to fix them yourself. Insulation on wire decays. Rubber breaks down. Gaskets dry up. Contacts get corroded. Keep your Escort around another 9 years and you'll learn all about that.
I drive a 24-year-old Dodge Ram pickup truck. The other day, the connector to my voltage regulator failed. It was corroded. The regulator didn't have a reference for the voltage on the battery, so it assumed the battery voltage was zero, and therefore pegged the charging current. +50A charge on my gauge - I pulled over as soon as I could, because my battery was boiling and my electrical system was running at 22 volts. (Only blew a headlight, though.) I pulled out my multimeter, checked a few connections against the service manual (kept stashed under the seat), found the bad connection, cleaned it with a pencil eraser, and the problem was fixed.
This is the sort of thing that will happen with *any* older vehicle. Period. There's no escaping it. If you like older vehicles and choose to drive them, you have to know what to do and be prepared to do it.
It's nice, though. Driving older vehicles has taught me to be resourceful, a skill useful everywhere. And I can diagnose a problem quickly, and have a lot of practice in assessing the severity of a situation.
The truck is insured for liability only, and pickup trucks are cheap to insure. $34/mo gets me $1,000,000 coverage in a city almost as big as Chicago. Besides that, I'm not paying out monthly car payments, so that money can instead go to fund other things - like a 401(k).
And besides, I just like the thing.
With a good tune-up, my truck is also the only vehicle I know that doesn't need to be plugged in to a block heater on a cold winter's night - it'll still start, first shot, on the coldest morning of the year. I frequently have to jump-start my boss's 2-year-old Integra. Why? Because, while my truck may be crude, it was built to last, and I take good care of it. The Acura was built to perform flawlessly for the first 100,000 miles and then be scrapped.
My truck gets an oil change - cheapest 10W30 oil and filter I can find - every month (3,000 miles). Every month, I also pop off all the wheels, check the brake linings, lubricate the parking brake cable with silicone grease, check the wheel bearings and balljoints looking especially for looseness or torn dust boots, and grease all the suspension. Takes about 2 hours every month. New air filter if it's visibly dirty or every three months, whichever comes first. I clean and regap the spark plugs every three months, checking the compression, timing and vacuum advance at the same time. (I'm impressed with the Bosch Platinum plugs I put in early this summer!) And while I've got the motor warmed up and I'm in my coveralls, I pop a vacuum gauge on the old Carter BBD carburetor and balance the metering rods, and re-set the idle.
Every fall, I spray another coat of paint on the underside of the body to prevent the floor and frame from rusting in the salty wet snow. Every week when there's snow on the ground, the whole underside gets washed off with hot water at a car wash. And every summer, I set aside at least one project that I'd like to do, usually because I enjoy them. Last year, I gave my truck the gift of air conditioning. This year, I'm going to repair some old rust damage on the truck, replace the windshield (there's a small chip in it), tap a couple of small dents out of the body and then treat Methusulah to another coat of Chrysler Forest Green Metallic paint.
Fire and Meat. Yummy.