Nichia to Ship Green Diode Laser

Read my posts. I never said laser projectors won't happen. Actually I said they would. When high power RGB diodes become available. DLP will go the way of the CRT. It'll be replaced by raster scanning beams.. pretty much larger higher powered pico projectors. I've said a couple of times I actually look forward to this, because while these units will likely only have singular diodes, which means the per diode cost will never sink as low as the 445's have.. it will mean that cheap high speed galvo's will come on the market with them.. which is awesome.. Pointers get old after a while honestly. Scanners are where the fun is.

What i've said about a dozen times now... is that you won't see high powered red or green diodes in DLP projectors. Meaning there won't be devices with craploads in them like the casio's with the blue's. If they're having to be scavenged from devices with only one of each color.. The per diode cost will probably average around $200 each.. assuming projector prices stay about the same. Which is fine by me. That's still reasonable while being higher than the average non-thinking 'tard will be willing to pay to be able to laze their buddies in the eyes as a practical joke or helpfully illuminate helicopters and planes showing off for their friends...

I thought I read somewhere that Sony was releasing a projector with R,G & B diodes, in the 6-8 watt range? Or was that just a rumor?

I haven't heard that anywhere.... but maybe. If what qumefox said is correct, probably not.

Sounds like just a rumor. Direct green is just now coming on the market in low powers. So it'll be a little while before it's power levels get strong enough to make it worth while unless it uses DPSS. Red, even multimode, hasn't made it much over 600mw

Also what kind of projector was this supposed to be? DLP? Scanning beam? 6-8W sounds awfully low for DLP. The casio's drive the blue alone at over 30W to get 2500 lumen.

qumefox said:

Sounds like just a rumor. Direct green is just now coming on the market in low powers. So it'll be a little while before it's power levels get strong enough to make it worth while unless it uses DPSS. Red, even multimode, hasn't made it much over 600mw

Also what kind of projector was this supposed to be? DLP? Scanning beam? 6-8W sounds awfully low for DLP. The casio's drive the blue alone at over 30W to get 2500 lumen.

Click to expand...

There are red diodes well over 600mW. The Sony "diodes" are just that, a diode array. Most likely way too expensive for any of us. Not to mention the beam specs would be insanely horrible...
If you two insist on bickering, at least know what you are talking about.

Pontiacg5 said:

There are red diodes well over 600mW. The Sony "diodes" are just that, a diode array. Most likely way too expensive for any of us. Not to mention the beam specs would be insanely horrible...
If you two insist on bickering, at least know what you are talking about.

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:crackup:
Lol, exactly, we have 635nm diodes well over a watt, they're just a pain in the @ss to use. You're not gonna stick one of those in a handheld :na:

Fine. So I was wrong on the reds. I was just going by the highest powered reds I remember being discussed.. Since i'm not in the market for red, I haven't looked to see what's available.

However if 1W reds are available, it's kinda more proof that what I was talking about earlier is correct.

But I think i'll just quit 'bickering' and unsubscribe from this thread.

No more 'bickering'??
May I be the first to say... Yay!

Wait... now what will I have to read?

That Sony referenced above was/is going to use red and blue multi-emitter laser diodes with a big green DPSS. There are posts about it on here somewhere, and elsewhere on the 'tubes.

But the multi-emitter diodes are a whole other level of complicated above and beyond the single-emitter, multimode diodes that we're getting with the 445nm stuff currently.

Sony seems to like that multi-emitter stuff, I've seen several papers on that stuff from them. I think it was going to be a DLP system, with how awful the output can be on those multi-emitter diodes.

For a DLP system, it can come down purely to $/lumen, but on top of that are also things like size, efficiency, effectiveness, etc. If laser diodes give you better $/lumen, then they're better than LED. If the laser array necessary is smaller than the LED array necessary, that might also be advantageous if size might be more important than cost. For some demographics, like the major videophiles, the tiny marginal improvement in performance from laser to LED might be worth extra money, and a laser DLP could give marginally better color performance than an otherwise-equivalent LED-lit DLP for the most demanding videophiles, I don't know. Lots of engineering and cost/benefit analysis going into these decisions, looking at the problem from multiple angles.

Is there any news on the 510nm greens?

I have on my desk a single emitter 1/2 watt 636 nm red in a 5.56 mm package. Intended use, displays such as picoprojectors. Cost, 65 cents a milliwatt in singles.

Downside, emitter is 2 x 50 uM, emission angles are about 5 x 55 degrees.

If you thought a high power Nichia blue was hard to collimate, no amount of low cost correction optics will turn this one into a pointer beam, not even ramming it through a fiber. The state of the art red on my desk is worse then a Casio Blue by a factor of 3.


I can get 1 watt single chip 640 nm reds, microlensed, about 650$, fiber coupled, about 900$. Output fiber is 225 uM fiber, so the beam diameter is horrid.

All are intended for DMD displays, because the first thing that happens, no matter what source,even arc lamp or led, it needs to go down a bounce tunnel to make the beam uniform. So a wide angle, big chip diode is just fine for video, but lousy for laser show or pointers.

I would expect the new direct green to be a wide chip as well, there is no reason to make a SLM, Tem00 beam for displays.

BTW, Hene and air cooled Argon sales are actually up the past two years. The investor driven development of 488 nm and 520 nm lasers with a quality beam has kept the price up on the DPSS blue with high beam quality. Thus making air cooled Argon still cost effective for many lab instruments. Hene is still going into semiconductor inspection because of narrow line width and beam quality. Its hard to beat inherent TEM00, few diodes can achieve it.

So sorry pointer folks, but the newer high power visible diodes have beams that just plain suck for your application, and for the most part are beyond correction, even if you throw 2/3rds of the beam power away.

There is no market right now for a 250 mW or 500 mW red less then 650 nm with a gaussian, classic beam profile.

I'm NOT going to name part numbers, I'm under NDA. The numbers I did give are slightly distorted but fairly accurate, within 5%. I cant give the actual numbers out, I cannot afford to give away my client's slight advantage in competition.

BTW, the less then 650 nm high power reds are running at such a high intracavity power density, that less then 1% back reflection can blow the emitter face off. The newest high power red diodes have a small piece of a highly heat conductive material that is transparent pressed against the emitter face, without that, they expire very rapidly.

Making a high power direct diode red pointer at short wavelengths above 150 mW is highly unlikely in the near future, if ever.

I just slightly bent quite a few rules to post this, so enjoy.. But NO questions will be answered.

Steve

Thanks for the news, even if depressing.

Bummer.... but then why would nichia make the 445nm diodes have such a relatively decent beam quality, if they were intended solely for projector use?

There's a BIG difference between those red diodes and the blue/green diodes though: the materials involved.

The 445nm diodes we see here have a 15um-wide ridge and can put out 1 watt of power. As you say, the red diode needs a 50um ridge to get half a watt of power. Clearly, violet and blue diodes can get more power out of narrower ridges than the red diodes. This has also been seen in optical storage laser diodes, which are forced to be narrow ridge to get single fundamental mode operation.

It very much remains to be seen what will be available in the green diodes in the future, as that work is mostly still just beginning. Heck, the Nichia stuff is still on polar GaN, along with everything else that has been commercialized in violet/blue/green. When/if semi-polar GaN becomes commercially available, all these things will change again, and steps forward will be taken.

And there are still other areas of research yet to be reached with violet/blue/green diodes. The technology is a decade younger than red diodes, it still has places to go.

ossumguywill said:

Bummer.... but then why would nichia make the 445nm diodes have such a relatively decent beam quality, if they were intended solely for projector use?

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Decent beam quality, ROFLAMO!

You probably didn't know the history///

Um, you know they make a very expensive SLM TEM00 blue diode don't you? With much better quality then the projector diodes? They made it long before the projector diodes came out. Going to the big chip with the ugly beam is what brought the price down for the projector.

This is why the projector diodes were priced at 700$ when they came out, as samples of the older, tem00 diode were 2800-3200$!!! I tried for years to get a sample of the Nichia blue, then imagine my disgust when the multimode ones dropped to 70$ over night. C'est la Vie..

Steve

LSRFAQ said:

Decent beam quality, ROFLAMO!

You probably didn't know the history///

Um, you know they make a very expensive SLM TEM00 blue diode don't you? With much better quality then the projector diodes? They made it long before the projector diodes came out. Going to the big chip with the ugly beam is what brought the price down for the projector.

This is why the projector diodes were priced at 700$ when they came out, as samples of the older, tem00 diode were 2800-3200$!!! I tried for years to get a sample of the Nichia blue, then imagine my disgust when the multimode ones dropped to 70$ over night. C'est la Vie..

Steve

Click to expand...

Well, you know... perhaps not "decent", but why didn't they just go with the crappy huge die you're describing with your red diode?


And I seem to remember on ebay a while back, for a few hundred bucks I think someone was selling single mode 445 diodes...