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Finally, a True Green Laser

timothy posted about 5 years ago | from the greenwashing-is-everywhere dept.

Displays 274

dusty writes "Remember those green lasers from Star Wars? Turns out that faking green lasers has been easy for years, but making true green laser diodes has been the stuff of science fiction. Until recently, that is. Now researchers from Japan have created the world's first true green laser diode. Until now, only red and blue laser diodes were available, and now with the addition of green, new TVs and projectors that are more efficient can be produced. And if you were wondering how green lasers pointers are already produced, it is a hack that involved doubling the frequency of an infrared laser. The new true green laser diodes have much higher efficiency than the current 6%, leading many to expect big time laser display breakthroughs in the near future. Ars Technica has a well-written article on this breakthrough."

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Robustness, too! (4, Interesting)

Sockatume (732728) | about 5 years ago | (#28850679)

A laser diode is much more robust than a laser diode and the frequency-doubling package of nonlinear crystals.

Re:Robustness, too! (5, Funny)

kusanagi374 (776658) | about 5 years ago | (#28850711)

A laser diode is much more robust than a laser diode

 

*head explodes*

Re:Robustness, too! (5, Informative)

Mr. Underbridge (666784) | about 5 years ago | (#28850795)

*head explodes*

"A laser diode is much more robust than (a laser diode and the frequency-doubling package of nonlinear crystals).

Re:Robustness, too! (1)

maxume (22995) | about 5 years ago | (#28850899)

Well, illiteracy is hilarious.

Or something.

Re:Robustness, too! (2, Funny)

alexj33 (968322) | about 5 years ago | (#28851301)

Just like in the academy. -Wesley Crusher

Re:Robustness, too! (1)

Richard_at_work (517087) | about 5 years ago | (#28852089)

Better, but you are still missing a closing quotation :) Have one on me: "

Re:Robustness, too! (5, Funny)

Allicorn (175921) | about 5 years ago | (#28850807)

(laser diode).robustness > ( (laser diode)+(frequency-doubling package of nonlinear crystals) ).robustness

Better?

Re:Robustness, too! (5, Funny)

Anonymous Coward | about 5 years ago | (#28850857)

expected ;

Re:Robustness, too! (5, Funny)

dmbasso (1052166) | about 5 years ago | (#28850995)

it was Python, you insensitive clod!

Re:Robustness, too! (0)

Anonymous Coward | about 5 years ago | (#28851071)

if sorry:
     forceMeToIndent()
else:
     missOutOnBraces()

Re:Robustness, too! (2, Funny)

Anonymous Coward | about 5 years ago | (#28851135)

I don't like the use of public fields, please use a getter method.

After that, please wrap the entire algorithm within a business rules engine so that it can be understood by business analysts.

Re:Robustness, too! (5, Funny)

noundi (1044080) | about 5 years ago | (#28851169)

Do it yourself, it's open source.

Re:Robustness, too! (4, Funny)

CarpetShark (865376) | about 5 years ago | (#28851545)

frequency-doubling package of nonlinear crystals
^ frequency not defined
      ^ doubling not defined
              ^ the reserved word "package" cannot be used in this context
                  ^ the reserved word "of" cannot be used in this context
                        ^ the reserved word "nonlinear" cannot be used in this context
                              ^ chamber in use, dilithium crystals cannot be accessed at this time
                                    ^ expected ;

Re:Robustness, too! (1)

Sockatume (732728) | about 5 years ago | (#28851165)

This is why I don't take wishes from genies. One recursive slip-up like that and laser diodes are indestructible.

Re:Robustness, too! (1)

C0vardeAn0nim0 (232451) | about 5 years ago | (#28852027)

you forgot operator precence. logical operators like AND/OR/XOR/NOT have precedence over arithmetic ones like + - * /

A laser diode is much more robust than a laser diode and the frequency-doubling package of nonlinear crystals.

see ?

Re:Robustness, too! (1)

sharperguy (1065162) | about 5 years ago | (#28852047)

If you remove the necessity for the frequency-doubling package of non-linear crystals, you also regain the lost robustness caused by having a more complex system.

Re:Robustness, too! (5, Funny)

Anonymous Coward | about 5 years ago | (#28850747)

A laser diode is much more robust than a laser diode and the frequency-doubling package of nonlinear crystals.

How waterproof are they? I've a few military applications regarding applying said diodes to a member of the selachimorpha order. Attached between it's snout and first dorsal fin would be the ideal configuration.

Re:Robustness, too! (4, Funny)

Eevee (535658) | about 5 years ago | (#28851759)

Would you settle for a member of the perciformes order with an attitude?

Re:Robustness, too! (1)

Smegly (1607157) | about 5 years ago | (#28850775)

And its application? A green laser makes a better laser sight than other colors. [gunsholstersandgear.com] . Progress... or not.

Re:Robustness, too! (1)

BubbaDave (1352535) | about 5 years ago | (#28851123)

And its application? A green laser makes a better laser sight than other colors. [gunsholstersandgear.com] . Progress... or not.

Killing people is going to be a regrettable necessity for some centuries to come.

Dave

BubbaDave has a problem. (0)

Anonymous Coward | about 5 years ago | (#28851823)

Well, thanks for your wisdom, BubbaDave. Are you volunteering to be killed?

Oh... You mean other people will be killed, and Bubbas like you will do the killing. In that case, you have a mental problem, don't you?

Re:Robustness, too! (2, Funny)

hobbit (5915) | about 5 years ago | (#28851921)

Killing people is going to be a regrettable necessity for some centuries to come.

[CITATION NEEDED]

Re:Robustness, too! (3, Funny)

BubbaDave (1352535) | about 5 years ago | (#28852045)

Geneva Accords, 32 Nations Summit, April 2039, Section 329, Paragraph 27.

Dave

Re:Robustness (1)

philpalm (952191) | about 5 years ago | (#28850849)

So will the Television industry bring back laser television technology now that they got a true green laser?

sweet! (5, Funny)

gEvil (beta) (945888) | about 5 years ago | (#28850689)

I can't wait to get my new RGB Laser TV(TM)! Finally all those myths about how you'll go blind from staring at the TV will be reality!

Re:sweet! (0)

Anonymous Coward | about 5 years ago | (#28850997)

Ineresting.

It could make a hell of a projection TV!

Re:sweet! (5, Funny)

Jurily (900488) | about 5 years ago | (#28851027)

I can't wait to get my new RGB Laser TV(TM)! Finally all those myths about how you'll go blind from staring at the TV will be reality!

Warning: don't watch TV with remaining eye.

Re:sweet! (3, Insightful)

impaledsunset (1337701) | about 5 years ago | (#28851361)

I don't think you need lasers to do this. Recently I made the mistake to turn a TV on, and what I saw and heard, can certainly make you deaf, blind and stupid.

as a physicist and a canadian it is only right for (4, Funny)

ILongForDarkness (1134931) | about 5 years ago | (#28850691)

me to be the first to say: "laaayyser".

Re:as a physicist and a canadian it is only right (1)

multipartmixed (163409) | about 5 years ago | (#28851151)

....what do other people say?

Re:as a physicist and a canadian it is only right (0)

Anonymous Coward | about 5 years ago | (#28851295)

Freakin' sharks with lazers on their heads.

Re:as a physicist and a canadian it is only right (4, Funny)

autocracy (192714) | about 5 years ago | (#28851907)

They say the same thing, but they say it after the Canadian physicist.

This means green jobs (5, Funny)

Teresita (982888) | about 5 years ago | (#28850705)

I'm sure Al Gore is thrilled with this news of green laser technology.

next step (1)

tverbeek (457094) | about 5 years ago | (#28850731)

This brings us one step closer to producing a Power Ring!*

*GL Corps version, of course. Making a Power Ring like the original Green Lantern's is just a matter of using the right kind of ancient magic.

Why are shorter wavelengths cooler? (1)

sakdoctor (1087155) | about 5 years ago | (#28850733)

Blue > Green > Red

At this rate, the next generation games consoles will need a UV power light.

Re:Why are shorter wavelengths cooler? (2, Funny)

fridaynightsmoke (1589903) | about 5 years ago | (#28850913)

Blue > Green > Red

At this rate, the next generation games consoles will need a UV power light.

I'm way ahead of the curve.. the front of my computer has a frickin' gamma ray emitter as ITS power light.

Re:Why are shorter wavelengths cooler? (1)

jeffasselin (566598) | about 5 years ago | (#28851061)

So? You only did that so you would turn green yourself. Green really IS better.

Re:Why are shorter wavelengths cooler? (0)

Anonymous Coward | about 5 years ago | (#28851307)

"It's not easy being green" - Kermit the frog

Re:Why are shorter wavelengths cooler? (2, Funny)

Cro Magnon (467622) | about 5 years ago | (#28852145)

*sigh* As usual, I'm way behind the times. I'm still using infrared, but I do plan to upgrade to the visible spectrum in the near future.

Fantastic (4, Funny)

Rik Sweeney (471717) | about 5 years ago | (#28850737)

All we need now is some true frickin' sharks and we're in business.

Lasers? Star Wars? (1)

pjt33 (739471) | about 5 years ago | (#28850739)

Were the energy weapons in Star Wars actually called lasers? That sounds uncharacteristically unimaginative.

Re:Lasers? Star Wars? (1)

ArcherB (796902) | about 5 years ago | (#28850773)

Were the energy weapons in Star Wars actually called lasers? That sounds uncharacteristically unimaginative.

They were called "Blasters", although "Light Sabre" can sound an awful lot like Laser if you say it fast enough and they did come in green.

Re:Lasers? Star Wars? (1)

Broken scope (973885) | about 5 years ago | (#28850845)

There were lasers, blasters, and turbo lasers.

Re:Lasers? Star Wars? (5, Funny)

Anonymous Coward | about 5 years ago | (#28850967)

Hate to break it to you. They were props.

Re:Lasers? Star Wars? (1)

Comboman (895500) | about 5 years ago | (#28851521)

Props don't have names?

Re:Lasers? Star Wars? (1)

CarpetShark (865376) | about 5 years ago | (#28851657)

But that's only because it all happened a long time ago, in a galaxy far away, right? And the real one all rusted? Right?

Re:Lasers? Star Wars? (1)

buchner.johannes (1139593) | about 5 years ago | (#28851851)

Imagine your paper is published on /., the first 10 minutes you are all excited and everything; then you can only facepalm ...

Re:Lasers? Star Wars? (1)

Nick Number (447026) | about 5 years ago | (#28850803)

They usually referred to them as blasters, but not every time. Going into the asteroid field in The Empire Strikes Back, Han said, "That was no laser blast; something hit us!"

Re:Lasers? Star Wars? (1)

Max Gene (1388439) | about 5 years ago | (#28850951)

Sounds to me like a laser blast was considered to be nothing, then, so they were hit by something more intense. Similar to how my friend wouldn't care if I took a laser pointer and aimed it at him...

Re:Lasers? Star Wars? (1)

multipartmixed (163409) | about 5 years ago | (#28851179)

Yeah, they were hit by matter instead of light. You know, like asteroids. In an asteroid field. The kind created, when, say, a big weapons platform annihilates a planet.

Re:Lasers? Star Wars? (1)

Bakkster (1529253) | about 5 years ago | (#28851505)

Or that they were hit by something that contained kinetic energy (a fast moving rock), rather than electromagnetic or heat energy (laser/blaster/etc).

Seems more to me like the difference between being burned and being hit: both hurt, might have each had the same energy, but you can tell the difference.

Re:Lasers? Star Wars? (1)

thisnamestoolong (1584383) | about 5 years ago | (#28850973)

If so there is something weird going on, considering the fact that whatever they fire from their guns moves considerably slower than even a bullet, never mind light. Some sort of charged particle, maybe? If they refer to it as a laser, could that just be a common misuse of the term by the uneducated masses a long time ago in a galaxy far, far away? Or have I just had too much coffee this morning?

Snow Crash (4, Interesting)

Derek Pomery (2028) | about 5 years ago | (#28850755)

Sweet. Now we just need it to draw on your eyeball.
And not blind you.
" Down inside the computer are three lasers - a red one, a green one, and
a blue one. They are powerful enough to make a bright light but not powerful
enough to burn through the back of your eyeball and broil your brain, fry
your frontals, lase your lobes. As everyone learned in elementary school,
these three colors of light can be combined, with different intensities, to
produce any color that Hiro's eye is capable of seeing.
          In this way, a narrow beam of any color can be shot out of the innards
of the computer, up through that fisheye lens, in any direction. Through the
use of electronic mirrors inside the computer, this beam is made to sweep
back and forth across the lenses of Hiro's goggles, in much the same way as
the electron beam in a television paints the inner surface of the eponymous
Tube. The resulting image hangs in space in front of Hiro's view of Reality."

Re:Snow Crash (2, Informative)

MukiMuki (692124) | about 5 years ago | (#28851419)

Sweet. Now we just need it to draw on your eyeball. And not blind you.

You mean like this [wikipedia.org] ?

Re:Snow Crash (1)

hobbit (5915) | about 5 years ago | (#28852021)

In primary school, I was taught that the primary colours are red, yellow and blue. I suppose what they really meant was magenta, yellow and cyan.

Re:Snow Crash (2, Informative)

Sockatume (732728) | about 5 years ago | (#28852201)

RGB is the additive set of primary colours, CMY is subtractive.

Re:Snow Crash (3, Insightful)

Lumpy (12016) | about 5 years ago | (#28852103)

I had that image hanging in view of reality for a while.

wearable computing and a decent HUD. Looks like sunglasses, and I'm just staring and grinning. I'm actually typing profanity at you, taking your photo, and surfing the net.

Problem is that wearable computers are not as useful as a nice fast pocket one. my Nokia 810 and iphone kicks the crap out of any wearable I have had over the past 15 years in my personal research.

Snow Crash tech is only useful for plugging in when you are a blob of goo at home never leaving your chair. The raging BS about logging in while riding his motorcycle will never exist as I could not even stand the speed and status info in my helmet when I used to race. Visual distractions while driving fast are not a good idea.

Just a tidbit from a guy that has had that tech in his life, it's not all glamorous or as useful as you think. I found auditory cues to be far more useful. I switched at the end of my racing to beeps to let me know when I was at the shift point and speed ranges. It worked great.

What Headline/Summary Nonsense (5, Interesting)

Anonymous Coward | about 5 years ago | (#28850779)

Firstly, I really don't see how the solid state lasers using frequency doubling are "fake" lasers.

Even so, outside the realm of small laser pointers, there are such a thing as gas lasers and they can produce a true green emission.

The possible breakthrough is the production of more efficient semiconductor lasers that emit in the green range, not the production of the first "True Green Laser".

Yeah, this is Slashdot...Whatever

Re:What Headline/Summary Nonsense (5, Informative)

wigaloo (897600) | about 5 years ago | (#28851173)

Let me add to what you have said: Green beams can be obtained from solid-state infrared lasers (e.g., Nd:YAG) by using KTP or KDP crystals, which combine two photons into one (!) with twice the energy/frequency. The resulting beam is collimated and coherent - i.e., the same as the original and any other laser beam. The technique was first demonstrated in 1961 [wikipedia.org] , predating this new discovery by almost half a century. Green laser diodes are most definitely interesting and useful, but to suggest that the green lasers from before were "fake" is incorrect. The new part here is having green as the fundamental frequency from a solid-state laser.

Re:What Headline/Summary Nonsense (1)

Kazymyr (190114) | about 5 years ago | (#28852111)

Even more, there are dye-based green lasers which are tunable too. Have been around for decades.

Also, I don't see how the existence of a (tentative) commercially available green diode laser will impact the development of "laset TVs". Unless of course you are talking of projectors.

Not doubling the infrared, but slowing by half... (-1)

JRHelgeson (576325) | about 5 years ago | (#28850821)

Green lasers have been created by using an infrared diode and running the light through a crystal that would slow the emitted light waves down to the 510nm wavelength to obtain green light. The side effect is that all the extra light energy being absorbed by the crystal generates tremendous heat, nevertheless, the emitted beam still has enough energy to pop balloons and start fires even at 90mw output.

Re:Not doubling the infrared, but slowing by half. (3, Interesting)

Dyslexicon (639846) | about 5 years ago | (#28850923)

If you were slowing down light to make it green you'd need to start with ultra-violet light, not infrared.

The real physics is well documented on Wikipedia. I recommend reading their page on non-linear optics. [wikipedia.org]

Re:Not doubling the infrared, but slowing by half. (1, Informative)

UnHolier than ever (803328) | about 5 years ago | (#28851085)

Nothing is slowed down. Light always goes at the same speed. Guess its name.

What happens in a non-linear crystal is that two infrared photons combine to make one more energetic photon. If you can achieve 100% efficiency, then you start with a beam of power P in the infrared and end up with a beam of the same power in green, but only half the number of photons, each photon having double the energy, at the same speed.

The heating comes from inefficiency (transparency is never 100%) of the crystal, not from slowing down.

This is all, of course, well-documented in the page you have linked to, but not read. A more specific page might be

http://en.wikipedia.org/wiki/Second_harmonic_generation [wikipedia.org]

Re:Not doubling the infrared, but slowing by half. (1)

noundi (1044080) | about 5 years ago | (#28851225)

The heating comes from inefficiency (transparency is never 100%) of the crystal, not from slowing down.

On the other hand 100% transparency would be completely useless as it wouldn't alter the wavelenght at all, right?

Re:Not doubling the infrared, but slowing by half. (1)

pjt33 (739471) | about 5 years ago | (#28851321)

Nothing is slowed down. Light always goes at the same speed. Guess its name.

Fred? John? Amelia? Wait, how many guesses do I get?

(As an aside, the speed of light depends on the medium through which it's travelling).

Re:Not doubling the infrared, but slowing by half. (3, Informative)

Hognoxious (631665) | about 5 years ago | (#28851353)

Light always goes at the same speed. Guess its name.

Let me c [wikipedia.org] .

Hang on a minute, the article says light travels at the same speed in a vacuum. Stupid intarwebs. I'll fix Wikipedia and you can do all the others, OK?

Re:Not doubling the infrared, but slowing by half. (1)

AndrewNeo (979708) | about 5 years ago | (#28851493)

Let me c [wikipedia.org].

+1 groaaan

Re:Not doubling the infrared, but slowing by half. (3, Insightful)

amorsen (7485) | about 5 years ago | (#28851363)

Nothing is slowed down. Light always goes at the same speed. Guess its name.

True in a vacuum, not true in practically anything else.

Re:Not doubling the infrared, but slowing by half. (4, Informative)

necro81 (917438) | about 5 years ago | (#28851579)

Nothing is slowed down. Light always goes at the same speed. Guess its name

That is not fully correct. It is true that the speed of light [wikipedia.org] , in a vacuum, is a constant. But, the speed of light through a transparent medium is something less than c. How much light gets slowed down by a medium is frequency-dependent, as described by snell's law [wikipedia.org] , which is how lenses are able to bend light.

The fact that the speed of light through a medium is less than c also allows for some more exotic phenomena, such as Cherenkov radiation [wikipedia.org] , created when a particle's velocity through a medium exceeds that medium's speed of light (but definitely remains less than c).

Re:Not doubling the infrared, but slowing by half. (0)

Anonymous Coward | about 5 years ago | (#28851719)

Nothing is slowed down. Light always goes at the same speed. Guess its name.

We're not talking about light in a vacuum you know. Did you really not know that the speed of light in a transparent medium varies inversely with its refractive index? So (for example) the speed of light in diamond is about c/2.4 (2.4 is the approximate refractive index of diamond).

In some specially constructed materials light can be slowed down to near walking pace or even temporarily halted.

True green laser? (5, Informative)

actionbastard (1206160) | about 5 years ago | (#28850835)

Title should read "True green laser diode". 'Green' laser output has been achievable for for more than three decades with Argon ion, Krypton ion, and Copper vapor lasers. This just makes it more 'convenient' to achieve green output.

Re:True green laser? (1)

RaymondKurzweil (1506023) | about 5 years ago | (#28850887)

You must be new here.

Re:True green laser? (1)

Loomismeister (1589505) | about 5 years ago | (#28851079)

The author of that article actually mentioned that we have been able to make green lasers, but that they are not efficient enough to be used. This true green diode really makes laser projection screens inevitable because it can become just as efficient as our red and blue colored lasers.

Green lasers, old news [Re:True green laser?] (1)

Geoffrey.landis (926948) | about 5 years ago | (#28851249)

The author of that article actually mentioned that we have been able to make green lasers, but that they are not efficient enough to be used.

Actually, the author of that summary mentioned that we have been able to make green diode lasers, but they are not efficient enough to be used for applications that need high efficiency. (they're used all the time for applications that don't need high efficiency-- laser pointers, for example-- take a look at google [google.com] ).

The author of the summary failed to point out that green lasers using technologies other than semiconductor diode lasers have been avalable for decades.

Copper vapor lasers [repairfaq.org] are quite efficient [wikipedia.org] , actually, although argon ion lasers [rp-photonics.com] efficiencies are indeed pretty low. Doubled YAG lasers are very commonly used for green-- a diode-pumped doubled YAG can get a wallplug efficiency of around 20%, IIRC.

Re:True green laser? (1)

lxs (131946) | about 5 years ago | (#28851199)

You forgot dye lasers. Those babies can be tuned to any color you want (within the range of the organic dye used of course) although CW dye lasers require powerful pump lasers and plenty of plumbing.

Re:True green laser? (1)

marciot (598356) | about 5 years ago | (#28851811)

> Even so, outside the realm of small laser pointers, there are such a thing as gas lasers and they can produce a true green emission.

Yeah, but you'ld look like a total dork showing up to do your PowerPoint presentation lugging around something that looked like this:

    http://www.walshcomptech.com/repairfaq/sam/sghi3ph1.jpg [walshcomptech.com]

Plus, they'ld throw you in jail for being a terrorist.

Re:True green laser? (1)

LatencyKills (1213908) | about 5 years ago | (#28852087)

Convenient? As in portable? As in more durable? Diode pumped 1.06um YAG lasers frequency-doubled to 530nm can fit in a pen, run off two watch batteries, and take a 5g impact. Portable, cheap, durable, and even scalable to a certain extent. Argon Ion lasers output a secondary line at 514nm, but admittedly they take about 70kW input power and require 8gpm or so cooling water, but they can be really durable, supporting years of operation in poor conditions. The only real difference I see these lasers providing is that it could be used to produce direct emission displays. Neat, but already entering the crowded field of plasma and LCD units.

Not fake (2, Interesting)

avandesande (143899) | about 5 years ago | (#28850893)

I am sure the guys building this laser [llnl.gov] would be more than a little pissed that you consider their laser 'fake' because it uses frequency doubling....

Re:Not fake (1)

thisnamestoolong (1584383) | about 5 years ago | (#28851251)

I am sure the guys writing this article [slashdot.org] would be more than a little pissed if you considered their article 'wrong' because you didn't read it...

Re:Not fake (1)

Volante3192 (953645) | about 5 years ago | (#28851337)

Way to take something out of context.

It's not a fake laser that produces green, it's a real laser that produces fake green. The lasers in current green laser lights emit infared, not green that just get filtered through emerald glasses from Oz.

What's so special about green? (1)

Candid88 (1292486) | about 5 years ago | (#28850921)

The linked wikipedia article states:

Green laser pointers[4] appeared on the market circa 2000, and are the most common type of DPSS lasers

Why? Whats so special about green laser pointers?

Re:What's so special about green? (1)

physburn (1095481) | about 5 years ago | (#28851075)

Its the best color for taking someones eye out. Adsorbed very well by your poor red retina. Rembember not to look into Laser beam with you remaining good eye.

---

Gadgets [feeddistiller.com] Feed @ Feed Distiller [feeddistiller.com]

Re:What's so special about green? (1)

betterunixthanunix (980855) | about 5 years ago | (#28851145)

The problem is that there was no known material that would act as a laser diode that emits green light -- that is, the materials which emit green light as LEDs are not suitable for emitting lasers.

Re:What's so special about green? (1)

Candid88 (1292486) | about 5 years ago | (#28851399)

But why are green laser pointers more popular than red or blue ones?

The implications of completing the RGB chart must be huge, but why are green laser pointers specifically better selling than other laser pointers? (unless ofcourse the Wikipedia article is wrong)

Re:What's so special about green? (1)

marciot (598356) | about 5 years ago | (#28851953)

Our eyes are very sensitive to green, hence green lasers appear to be a *lot* brighter than red or blue ones. With green lasers, the beam itself is often visible (due to dust particles in the air), giving it that old-school sci-fi laser effect you don't get with the red ones. If you actually were to compare a red and green laser, you would know why green was by far the most popular. I've never actually seen a blue laser, but I guess it would be even dimmer than the red.

Re:What's so special about green? (1)

lxs (131946) | about 5 years ago | (#28851305)

Green is very visible, plus the fact that 1064nm->532nm crystals were already in production for frequency doubling the output of Nb-YAG solid state lasers. (These crystals only work efficiently over a narrow range of wavelengths)

Re:What's so special about green? (0)

Anonymous Coward | about 5 years ago | (#28851967)

There's a difference between a Laser Diode and a Diode Pumped Solid State Laser, and therein lies your answer.

The most popular laser diodes are red, but you don't need any tricks to produce a red laser, it's reasonably straightfoward. Green and blue laser diodes use frequency doubling, and are thus DPSS lasers. So what the Wiki actually says is that green lasers sell better than blue ones, which is unsurprising, given how expensive blue lasers are at the moment.

Yay (1)

Setheck (1317019) | about 5 years ago | (#28850931)

So when can I buy my working Light Saber?

Re:Yay (1)

Tordre (1447083) | about 5 years ago | (#28851297)

silly jedi, if you went to the dark side your colour would have been available for years (650nm ftw). Mine is almost working i just need to use the force to tell the laser where to stop.

The Laser Display Board has existed for years. (1)

EWAdams (953502) | about 5 years ago | (#28850937)

Every fan of I'm Sorry, I Haven't a Clue knows all about it.

Next you'll be telling us that Japanese scientists have given Samantha a voice.

My eyes! (2, Funny)

karnal (22275) | about 5 years ago | (#28850971)

The goggles do nothing!

Sharks (1)

AdmiralXyz (1378985) | about 5 years ago | (#28851063)

There, I said it. Now we can get on with useful comments.

Green (1)

macbuzz01 (1074795) | about 5 years ago | (#28851109)

This is wonderful news! I should have the backing of environmentalists behind my plan of attaching lasers to sharks!

Blackadder (3, Funny)

kyriosdelis (1100427) | about 5 years ago | (#28851277)

Oh, Edmund... can it be true? That I hold here, in my mortal hand, a nugget of purest Green?

Greener Sharks (1)

jlebrech (810586) | about 5 years ago | (#28851377)

And don't forget to mention more ecofriendly sharks.

Been nice knowing ya... (3, Interesting)

rayharris (1571543) | about 5 years ago | (#28851451)

Goodbye DLP and LCD TVs and projectors.

Laser TVs:
- Have higher contrast ratios (talk about true black)
- Produce a range of colors broader than HDTV
- Use less energy

Unfortunately, they're still expensive. The only one that's available that I know of is the Mitsubishi Laservue. It's $7000 over at Amazon (http://www.amazon.com/dp/B001IAAD3K).

Hopefully, this green laser will make Laser TVs more of an (afforable) reality.

This is a pulsed laser, not continuous wave (4, Informative)

rcb1974 (654474) | about 5 years ago | (#28851679)

From the article it says, "At Sumitomo Electric, they have overcome this problem by developing a GaN crystal which inhibits the efficiency drop, resulting in room temperature pulse operation of a laser diode emitting in the pure-green region at 531nm." Having worked on development of GaN blue lasers, there are a lot of challenges to getting a reliable, continuous wave (CW) diode laser that operates at this wavelength. My guess is they hammered their green diode laser with very short high power pulses just to get it to lase. So it is probably not a very useful laser if it cannot operate in CW mode.

In other news.. (1)

haploc (57693) | about 5 years ago | (#28851755)

Clearchannel has developed a new business income stream after it finally found the means to project its posters on the moon!

Why not InGaN? (1)

Fujisawa Sensei (207127) | about 5 years ago | (#28851909)

Could somebody elaborate a little bit more on this?

What is the issue with just using Indium to tune the band gap of GaN laser to the green and just having an InGaN laser?

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