I think it's beginning: Direct Greens (almost) in the Wild

With CES going on down in Vegas, we've got new Picos popping up left right and center. Most notably, two that I've found thus far are using Direct Greens:

WOWee ONE Launches Green, Laser-Based Pico Projector at CES | News & Opinion | PCMag.com

MicroVision Goes Direct Green to Spark Projection Revolution - MarketWatch

Pricing will be a big question mark. But as far as pico projectors go, these laser-based units actually fall relatively low on the brightness scale. My gut says that you can't charge more than $349 for a low-brightness pico projector intended for mobile phones and other portable media gadgets, in short-throw single-viewer environments. If there's a single mode blue ($50 value) and single mode red ($50+ value at least) inside, then these might be good harvesting resources.

Awesome. Nice Find.:beer:

Given the current price of $250 for a direct green diode, a projector at $350 with $100 of other diodes in it is pretty sweet. I can't wait until they start coming down in price even more. Besides, it would be nice to have one of those projectors, haha.

I just finished my first green build tonight. Im excited to see much smaller ones in the near future

Sigurthr said:

Given the current price of $250 for a direct green diode, a projector at $350 with $100 of other diodes in it is pretty sweet. I can't wait until they start coming down in price even more. Besides, it would be nice to have one of those projectors, haha.

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Keep in mind the $250 price tag for direct greens is the price for single diodes. The companies making these pico projectors will be placing huge orders for diodes. When ordering 10s of thousands of diodes they get the diode price down to between $35 and $90 each. As was said if the price for these projectors is around $300-$350 then it will still be economically feasible to harvest diodes and pieces from them. But we also have to keep in mind how much people who do the harvesting are going to charge. With the k@$10 projectors you could sell the fans, the lenses, the mirrors, the red LED phlatlight etc which helped recoup the costs. These pico projectors don't have as much of that stuff that would be "sellable".

I'm really hoping for (and I'm sure everyone else is) another k@$10 type of situation where a manufacturer uses green diodes in a full size projector but several things have to happen for that to be feasible first.
1. Green diodes need to be more powerful, at least 250-450mW
2. The price of the diodes needs to go down to the point of being a better option than the current green technology.

sassafrass686 said:

I just finished my first green build tonight. Im excited to see much smaller ones in the near future

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We're talking about actual direct green diodes. Not DPSS greens. Big difference

sopark4000 said:

We're talking about actual direct green diodes. Not DPSS greens. Big difference

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Yeah The big difference is the size... (and price, and obviously the physics since the direct greens aren't infrared diodes)

Thats why I'm looking forward to smaller green builds.

sopark4000 said:

I'm really hoping for (and I'm sure everyone else is) another k@$10 type of situation where a manufacturer uses green diodes in a full size projector but several things have to happen for that to be feasible first.
1. Green diodes need to be more powerful, at least 250-450mW
2. The price of the diodes needs to go down to the point of being a better option than the current green technology.

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I disagree:

1) Why do green diodes need to output 250-450 mW before they could be used in a KasEO type scenario? Take the example of a projector running 445s at ~750mw. The dot produced is equivalent in brightness to around 45mW of 510 (Raleigh doesn't matter either).
Dot: (445nm 750mw) vs. (510nm 44.43mw)

At the very least, you'd expect that we're already at the point where they could toss 24x of the direct greens that we have now, into a projector, and you've got adequate power. But it's actually a bit better than that, because remember that half the purpose of those current 24x 445s is to create green via the phosphor disc. So you'd need fewer than the current 24x 445s if you had 510s, which also suggests that you'd need fewer than 24x 510s, since we're really only balancing less than 24x 445s. Long story short, even present power levels for DG diodes are fine for a KasEO type scenario.

2) Cost is already fine if you used the 510s. The "retail" on DG diodes is already less than half the "retail" on 445s from Nichia. Assuming similar bulk-purchase discounts, the DG diodes should actually be cheaper than 445s to someone like KasEO, right now.

sassafrass686 said:

Yeah The big difference is the size... (and price, and obviously the physics since the direct greens aren't infrared diodes)

Thats why I'm looking forward to smaller green builds.

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There's much bigger differences than the size.
There's power consumption, heat dissipation, power stability, and the "abuse" the laser can take. Drop a DPSS green on concrete and chances are the crystals will either have dislodged or shattered. Drop a 445nm diode laser on concrete chances are you can pick it up and it will be fine. I'm still interested in getting one of the direct greens right now but I'm getting my 1,300mW+ 532nm soon and a 1,000mW+ 650nm right after that. If the 505-520nm diodes are still available after that then I'd like to buy one.

Wow $250.00 or even $350.00 is not that bad for 3 laser diodes and one green one at that when you
consider we used to buy the whole Bluray writer for $210.00+ just to get one 12x Bluray diode :crackup:

thanks for sharing :beer:

Side note
if you look at the Ka5io green Phosphor wheel you will notice that~3/4th is green with the rest clear to allow ~1/4 of the 445 nm to pass thru to the dichros and FS mirrors so more than 'half' of the 445s power is used to make the green. So I am thinking that way more than a single DG would be needed to make the green in a full size pj.


hak's dos entavos.

It's probably not quite this simplistic, but if we took a very rough look at this, just to "get a sense" for the powers involved, we could actually work backwards.

- If 3/4 of the blue goes to create green, then 1/4 of the blue is there for blue's sake.
- If blue diodes didn't need to worry about creating green via the phosphor, then we might only need 6 blue 445 diodes.
- If those 6 blues were running at 750mW each, we'd be looking to balance out about 4500mW of blue.
- 4500mW of blue is balanced in brightness by a bit under 300mW of 510nm.
- 300mW of 510 would imply... 6 diodes.

So perhaps we'll actually see 6x 445 and 6x 510 diodes in future projectors.

I would note, that while this seems far-fetched, remember that phosphor creation of green is very inefficient at present. I would further remind everyone that as the 510s become 520s, we'll need less of them.

Finally, in reality, it will probably be a long time before KasEO moves to DGs. There's just not likely a huge motivation for them until they run out of present stock.

^^^ my thoughts too.

rhd said:

It's probably not quite this simplistic, but if we took a very rough look at this, just to "get a sense" for the powers involved, we could actually work backwards.

- If 3/4 of the blue goes to create green, then 1/4 of the blue is there for blue's sake.
- If blue diodes didn't need to worry about creating green via the phosphor, then we might only need 6 blue 445 diodes.
- If those 6 blues were running at 750mW each, we'd be looking to balance out about 4500mW of blue.
- 4500mW of blue is balanced in brightness by a bit under 300mW of 510nm.
- 300mW of 510 would imply... 6 diodes.

So perhaps we'll actually see 6x 445 and 6x 510 diodes in future projectors.

I would note, that while this seems far-fetched, remember that phosphor creation of green is very inefficient at present. I would further remind everyone that as the 510s become 520s, we'll need less of them.

Finally, in reality, it will probably be a long time before KasEO moves to DGs. There's just not likely a huge motivation for them until they run out of present stock.

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Agreed. Thats what I was trying to explain (sort of) in another post. A full size projector using direct green diodes wouldn't need that many of them because of greens visibility. Plus they will only end up using green diodes if the powers can be increased thus reducing the number of diodes needed even more.

But back to the subject at hand. $350 for one of these pico projectors isn't bad at all. Like FP said. You used to have to pay $210+ just to get one BR 405 diode.

Important question. Do we have any idea how much these projectors are actually going to cost? Does anyone have a cited source for the $350 number. Is it just an estimate based on the current price of pico projectors? :anyone:

rhd said:

It's probably not quite this simplistic, but if we took a very rough look at this, just to "get a sense" for the powers involved, we could actually work backwards.

- If 3/4 of the blue goes to create green, then 1/4 of the blue is there for blue's sake.
- If blue diodes didn't need to worry about creating green via the phosphor, then we might only need 6 blue 445 diodes.
- If those 6 blues were running at 750mW each, we'd be looking to balance out about 4500mW of blue.
- 4500mW of blue is balanced in brightness by a bit under 300mW of 510nm.
- 300mW of 510 would imply... 6 diodes.

So perhaps we'll actually see 6x 445 and 6x 510 diodes in future projectors.

I would note, that while this seems far-fetched, remember that phosphor creation of green is very inefficient at present. I would further remind everyone that as the 510s become 520s, we'll need less of them.

Finally, in reality, it will probably be a long time before KasEO moves to DGs. There's just not likely a huge motivation for them until they run out of present stock.

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There's also the possibility of them using 12x 445 and 12x green. Not that 6000+ lumens are really required from a projector but who knows?