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Shuji Nakamura Awarded the 2006 Millennium Prize
Mictian writes "University of California professor Shuji Nakamura, the japanese inventor of the bright green, white and blue GaN LEDs and a blue laser, has been awarded the 2006 Millennium Technology Prize. While blue LEDs are considered cool and thus needful things by most nerds, Nakamura adapted his blue LEDs to make a blue laser in the mid 90s. The next generation optical storage formats, HD-DVD and BluRay, are of course both based on blue laser. Also, his white LEDS need far less energy than normal incandescent lamps and can thus provide plenty of opportunity for energy-saving in the industrialized world. But probably the most significant future application for Shuji Nakamura's invention comes in the form of sterilizing drinking water, since the the water purification process can be made cheaper and more efficient with the use of ultraviolet LEDs. This can improve the lives and health of tens of millions people in developing countries."
Since when does HD-DVD use a blue laser?
Shuji Nakamura got boned by his employer Nichia, and it's got to feel sweet for him that he's getting recognized for his work anyway.
"The court actually valued Nakamura's contribution to the company at 60.4 billion yen, based on Nichia's sales and the revenue that it might theoretically have received from licensing a key patent relating to the epitaxial growth of LED material."
http://www.ledsmagazine.com/articles/news/2/1/5/1
"But probably the most significant future application for Shuji Nakamura's invention comes in the form of sterilizing drinking water, since the the water purification process can be made cheaper and more efficient with the use of ultraviolet LEDs. This can improve the lives and health of tens of millions people in developing countries."
This is absurd. No one with even the slightest clue about such things would ever make such a statement. Nakamura's blue and UV GaN/InGaN/AlInGaN leds and laser diodes are great but they will not be used for this purpose. The all emit in the near UV (350 nm or greater) this sucks for killing microorganisims. You want to cause a kink in a bacteria's dna by dimerizing adjacent thymine molecules, thus inhibiting replication. The germicidal efficacy curve which describes this phenomenon peaks at 260nm way below any LED with any kind of reasonable efficiency. A tenuous mercury plasma in a quartz bulb however, will blast out something like over 80% of its light right at this wavelength! There is no way you are going to beat the hugely efficient and dirt cheap germicidal uv lamps already on the market any time soon.
- "Hear that?! The percolations are imminent! Cease your ingress!"
It's not just the saving in energy consumption, either. LED-based lightbulb alternatives generally have lifespans in the tens of thousands of hours, compared to around 1000 hours for a good quality incandescent bulb. Most of the LED bulbs that I've seen have around 50,000 to 60,000 hour lifespans, which if you do some quick maths will work out to around 6 years of constant use. They're a lot more expensive than a single incandescent bulb, but if you actually sit down and figure everything else, the equivalent number of standard incandescent bulbs will cost you more. That's not even touching on the significant power reduction, either.
TFA explains "blue lasers," summary misquotes as "ultraviolet LEDs". Whatever, same difference.
Nakamura is not just an LED guru, he's more generally a wizard of light and... light, I guess.
Your right, it doesn't.
405nm falls into the category of Violet (380-420nm). Blue would be between 440 and 490nm.
I wonder if/when we'll ever start using ultraviolet lasers to access data? (Maybe someone already does...?)
To be clear, she's a professor at University of California, Santa Barbara (UCSB) and not University of California, which is usually associated with Berkeley, being the 1st UC in the state.
HD Trailers
Actually, the recent energy bill banned the manufacture and import of parts for incandescent signals in the United States as of January 1, 2006. Existing stocks may be used until they run out, but the upgrade to LED signal tech makes sense. One of my co-workers is a councilman for a small municipality with one traffic signal. The recently converted it to LED. He forwarded us the e-mail from the Public Works department telling that the power bill for the signal was $30 for a month of LED instead of the $150 per month with incandescent. One signal will save the town $1200 a year. Multiply that cost and energy savings by the number of traffic signals in the United States and you'll see why LED traffic signals are catching on.
Interestingly enough, white LEDs (as opposed to RGB LEDs) are usually either blue or UV LEDs with a phosphor coating, much like a fluorescent light bulb's. So the LED itself is in fact monochromatic, or as nearly so as LEDs tend to be. The mechanism behind photon emission in LEDs (and diode lasers, which are nearly the same thing) strongly favors emission of photons clustered very tightly around a single energy level.
Ce n'est pas un vrai mouvement de robot!
Originally I believe they were offered as a "forklift upgrade", but now are available as screw-in units at least for some models.
If a town is cash-strapped the best thing for them to do is replace all the red bulbs first, then the green, and the yellow at their leisure. The red bulbs are cheapest and on average they are turned on the most. Once they are replaced the savings from them can be applied towards the more expensive green bulbs. Really power wise most yellow lights aren't that economical to replace, but they get replaced anyway because the LEDs last longer and changing the bulbs is expensive.
Someone had to do it.