Very nice white light from my red, green & Blue LS's.

[flash....]

Very nice white light from my red, green & Blue LS\'s.

I wired up three 1 watt stars (Red, Green & Blue) and look at this very nice white spot they cast.
I think I can do even a nicer spot if I took a little time and made slight alignments using shims.
This shot is close at 5 feet! (Anything closer and you start to see the seperate colors... My hand.)
And of course the farther you go away the nicer the white light gets.
I think I'm gonna make this into a single head 3D light. Can you fit three stars in a 3D Mag???
It looks really cool from a distance too!

 

[ikendu]

Re: Very nice white light from my red, green & Blue LS\'s.

I used to wonder how this would work out with three 5mm LEDs. Look's like a pretty cool result!

 

[James S]

Re: Very nice white light from my red, green & Blue LS\'s.

I was experimenting with this also, it's great fun Somewhere while surfing LED info pages I found a page that listed how many of each color of different kinds of LED's you would need to make a decent white. Needless to say buying multiple exotic LED's was not in the budget of my original experiment. So I just went to radio shack. They didn't have a high brightness red that would work, so I got 2 yellows and a blue. After all, yellow is already red and green mixed together.

It actually worked pretty good. You can see it on my LED page below. It would be very dim compared to yours though!

I really like the idea of using luxeons for this! Nice work.

James

 

[r2]

Re: Very nice white light from my red, green & Blue LS\'s.

Greater efficiency is an advantage of this setup as is control over the exact tint, but the tint thing is also a tricky part. Variation in individual LEDs is great enough to cause headaches getting a consistent white. Also, the different colors respond differently to diminishing current. As the batteries fade, the tint will vary. I think you'll still see loss of brightness over time (though not as much as whites since there is no phosphor) which will of course happen at different rates with different LEDs so that will affect your tint as well.

It's an appealing idea that has come up before but there are some difficult issues to overcome. The beam pattern isn't as nice with colored LEDs either so even if you get the different emitters with just the right amount of power you'll see artifacts in the composite beam.

Two main approaches come to mind: allow manual control over the three component colors so the user can tweak the tint easily or attempt to regulate the output. You'd have to address all of the above problems (emitter variations, different response curves to power variations, different aging characteristics) to make an automatic regulator. In the end, you still wouldn't get as nice a beam as a phosphor coated emitter since the phosphor has a smoothing effect.

- Russ

 

[rlhess]

Re: Very nice white light from my red, green & Blue LS\'s.

look at Color Kinetics (I believe it's http://www.colorkinetics.com/ )

They are doing this and have control circuitry to boot!

Cheers,

Richard

 

[hank]

Re: Very nice white light from my red, green & Blue LS\'s.

Or this:
http://www.emanator.demon.co.uk/bigclive/rgb.htm

 

[papasan]

Re: Very nice white light from my red, green & Blue LS\'s.

man, i'm getting a headache just looking at the picture, i think the real thing would drive me insane in short order.

try some of those old 3D glasses, you know the red and blue lenses, and see what happens =).

 

[r2]

Re: Very nice white light from my red, green & Blue LS\'s.

You could probably get great results in area lighting. For a flashlight I think the typical CPFer is too picky about beam quality to be easily satisfied with an RGB solution, though.

I'd be interested to see how well this works with bare LS emitters used as flood lights like the Inretech 3D maglite 6 LS adapter.

- Russ

 

[shipinretech]

Re: Very nice white light from my red, green & Blue LS\'s.

I'm not saying yes, and I'm not saying no. But we have thought about it. It won't be quite as good as the LS with phosphor because the phosphor does wonderful things for diffusing the light from the dies. I think it would be unacceptable with a collimnated solution, but with emitters only, it might be worth persuing. I would LOVE to do this with 5W parts while waiting for the white emitters to come out, but they don't make a red or yellow 5W yet, so there you go.

If you want to buy a three color "white" 1W Super6, we'll sell it to you.

 

[hotfoot]

Re: Very nice white light from my red, green & Blue LS\'s.

Originally posted by r2:
You could probably get great results in area lighting. For a flashlight I think the typical CPFer is too picky about beam quality to be easily satisfied with an RGB solution, though.

I'd be interested to see how well this works with bare LS emitters used as flood lights like the Inretech 3D maglite 6 LS adapter.

- Russ

<font size="2" face="Verdana, Arial">I've tried a RGB experiment as shown above with bare 1W batwings emitters and even with a emitter spacing of only about 15mm (which, according to Lumileds, will require extraordinary thermal management beyond even that detailed in AB05), the various colored LEDS will cast their own shadows, each one slightly offset from the others, giving you that same pyschedelic effect pictured above. Funky for parties, but very disorientating if you're trying to read or work. This effect is utterly horrible particularly at the fringes of both the beam itself, as well as any shadow cast within that beam.

Color-wise, my setup used varistor-knobs to control current (although in somewhat large increments) to each LED and I was able to achieve some very nice "in-between" colors and various shades of white. Tricky and fun in getting the desired colors, but I'm having a hard time figuring out how someone would cheaply be able to replicate this sort of setup en-masse.

Luminous efficiency-wise, a tri-color emitter setup seems less bright than an all-white emitter trio. I was hoping that since colored LEDs weren't doped with light-smothering phosphor, they'd put out more. Alas, I was disappointed. Its even dimmer if you tweak to get those more incandescent, "warmer" shades of white.

As expected, color rendering is quite good and mimics incandescent lighting effects rather well since the spectral content is fuller.

To eliminate color fringed multi-shadows, I think the Color Kinetics way of using a large array of 5mm LEDs works better than putting a thick diffuser as would be necessary with a luxeon color array. And diffusers cut light output further. Maybe that's why there simply aren't that many RGB LED lighting solutions for mainstream users like us - its still complex, expensive, hard to manufacture consistently and relatively inefficient.

 

[darkgear.com]

Re: Very nice white light from my red, green & Blue LS\'s.

Someone ask Eternalight to make LS versions of the Rave'n 2. That would be really cool.

 

[Albany Tom]

Re: Very nice white light from my red, green & Blue LS\'s.

Am I right in guessing that an advantage of this is that they shouldn't dim, as some (all?) white LED's may do? Direct light from the LED, rather than a phosphor. More efficient, maybe?

Anyway, very cool. Now we need one that has knobs on it so you can make any color. Time to start building....

 

[B@rt]

Re: Very nice white light from my red, green & Blue LS\'s.

Originally posted by Albany Tom:

Now we need one that has knobs on it so you can make any color. Time to start building....

<font size="2" face="Verdana, Arial">Cool.
How about using the electronics of a Sauce Lightwand for control? would it be possible?