Luxeon 1w versus array of 10000mcd Leds

Is possible to obtain luxeon performance from an array of 10000mcd leds?

And with an array of overdriven leds (say @ 50ma)?

cheers
/ubbthreads/images/graemlins/blush.gif

A LS typically has better color than a Nichia. you can match the total light output of a LS by a bundle of Nichias, but you may have to add some filter to match the color. Also the optic design will be more difficult when you spread the light source out.

but beside color likes/dislikes, can you obtain more from a bunch of leds than with a LS?

cheers

Sure,
This is brighter than the LS
http://ledmuseum.home.att.net/ex60.htm

i don't think small leds are better than 1W lux in terms of both brightness and color (and efficiency).
taking for example, led driven at 30 mA produces about 2 lumens. lux at 350 mA gives about 30 lumens. that means it needs at least 15 leds to get that same brightness. so multiply the 30 mA by 15 we get 450 mA. need more power to produce same brightness. Beside, it would be a more circuit challenging to put an array of leds to replace luxeon.

but then again, at low power, leds will be more efficient. just don't try to match the output of lux using array of leds. They just simply not worth it. An array of leds is better suited as signalling light, IMHO. So some leds can be dimmed or blinked to liking.

just my 2 cents

But nichia has just upped their efficiency 50% so 10 B1S nichias = 1 Luxeon in terms of lumens out. Heat sinking is easier and the lens is the LED so there are some advantages.

For a flood, you can get a fairly good result using multiple nichias, asuming that you don't care about the color. When comparing luxeons, there are a VERY wide range of outputs. An R binned 1 watt can produce up to 51 lumens from 350 ma.

If you want a hot-spot, you can more easily focus a single light source such as a luxeon.

Even assuming 3 lumens per led at 30ma, 10 of the new nichia will still be only 30 lumens and harder to collimate. That's still a lot of light.


Daniel

i don't think an array of LED's is compatable with a reflector like a luxeon is..

There are also space-efficiency issues with LED arrays.

Although, if they get the output on multi-chip 8 and 10mm LEDs up, it might be a more viable alternative since heat won't be quite the consideration it is with high power-density Luxeons.

If you shop around for your LEDs and other components, you can probably make a LED array for less than a Luxeon that's equally bright.

[ QUOTE ]
idleprocess said:
If you shop around for your LEDs and other components, you can probably make a LED array for less than a Luxeon that's equally bright.

[/ QUOTE ]

Theeere you go!, I purchased 100 leds from besthonkong and the whole package was less than $30 shipped to Argentina. For that kind of money I can only afford 2 x 1w luxeons+shipping from the sandwitch shoppe (and their prices are niice).

I still want to know what happens when you compare an array of leds vs a LS at say 10 meters (aprox 30 feet) /ubbthreads/images/graemlins/smile.gif

I don't know where you guys are buying your Luxeons, but you are apparently paying way too much.

I haven't priced 1W Luxeons from Future Electronics, but the 3W Luxeons are $8, and the 5W Luxeons are $24... I would expect the 1W Luxeons to be substantially less than $8.

Scott

Um, I believe the 1W's are $8 and the 3W are $15.
Taken from the FA site:

1+ :15.75
10+ :14.00
250+ :12.25
1000+ :8.75
5000+ :8.14

You're right, then... if I buy more than 5000 /ubbthreads/images/graemlins/wink.gif

Well, apparently they don't have their "real" prices on their web page.

I ordered 10 Luxeon V's a while back and paid $24 per led. I ordered 2 Luxeon V's just a few weeks ago and paid $24 per led. They have been listed on their web page as $43.20 for a long time.

I ordered 2 Luxeon III's about 2 months ago and paid $8 per led.

Perhaps they just like me or something.

Scott

Hmmmm, this is very possible. I DID buy a 5W over the phone for $24, even though the listed price was almost double that.

Hm. I just participated in a group buy and paid ~$15 for LS III stars (they were pulled from a known bin, so paying a bit over retail is allright), but at ~$8/ LS III, I'd be willing to play the lottery a bit...

Oh, and as far as LED arrays go... if you go with SMD leds, high-flux "spider" LEDs, or some of the 5mm "rectangular" LEDs (I have a small handful of these - 280mcdX120 - hell of a lot of light), you can get far better emitter density than you can with round 3/5mm parts.

Does anyone know a good cheap place to buy the Luxeon LED 1W and 5W? If you do, please let me know. I found the cost of the typical 1W @ $11 and 5W @ $45.

Thanks

LEDsupply sells 1W LSs (and specifies the bins they came from) for ~$9-$10 each.