RGBrainbow

Hi,
have a look at this:
http://www.laminaceramics.com/news/101804.aspx
regards
joachim

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plot

I... want.



And I want it right now. :cry:

Oznog

Nice! I looked at their emitters they're already got in production. Luxeon is still the king of power emitters on a per-device and per-watt basis, however. The Laminas might be easier to mount in many cases, Luxeons have a thermal slug in back which has to be heatsinked but can't be connected to anode or cathode and conventional insulators (silicone pad, mica, etc) won't work, and there's no screw holes etc to mechanically bolt the device down either.

http://www.digikey.com/scripts/dksea...=us&vendor=521

plot

Luxeons arn't cheap either, and are sometimes hard to find. Wish I could get my hands on a few 5w white Luxeon stars...

Oznog

http://www.luxeonstar.com

Not hard to get ahold of at all, they're in stock. Now a 5W Luxeon Star white is $41, but the numbers just don't make sense over the $15 3W. The 3W can do 65 lumens @ 2.6W, or 80 lumens @ 3.9W. 5W can put out 120 lumens. Problem is, that 5W emitter is harder to keep cool, and that light output rating is only for a cold emitter. As the die warms up, it generates less light while using the same amount of power.

So, in addition to costing more than it should, you may find it difficult to sink that much heat and thus make the light output more similar to the 3W.

williB

go Jersey..! . . lol

jrz126

oh no, am I going to have to redo the leds in my roof again :wink:
Thats some cool stuff right there. If they can make something like that, then why are we still using power hogging incandescent bulbs? LED bulbs would save you a ton on your electric bill and they would last a super long time

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Jeff Zimmerman
To the optimist, the glass is half full.
To the pessimist, the glass is half empty.
To the engineer, the glass is twice as big as it needs to be.

Phasor

This is why there is a big push towards using compact fluorescent lightbulbs (CFLs). An 11W CFL is apparently equivalent to a 60W incandescent bulb, though in my experience, they are nowhere near as bright, and the colour rendition is crappy.

plot

well, in my experience i've never come across a 120v or a 220v LED... and stepping it down to 3volts probably wouldn't be efficient at all.

but we can always hope.

williB

we all arent using power sucking incandescents..
i use three CFL's ,...two 11W and a 28W most of the time ..they work well
those LED arrays look sweet..

williB

OMG i got bleeped..

jrz126

why would it have to be a single led, why not have multiple leds wired in series?

__________________
Jeff Zimmerman
To the optimist, the glass is half full.
To the pessimist, the glass is half empty.
To the engineer, the glass is twice as big as it needs to be.

plot

becuase when that 120 volts worth of current hit's that first LED... *poof*

never wire LEDs in series :wink:

jrz126

You can wire them in series. As long as you have a current limiting resistor, you'll be ok.
The current is the same throughout the whole string. the voltage drop across the leds would reduce the 120V down to a small value then a small resistor is also placed in series to limit the current.

__________________
Jeff Zimmerman
To the optimist, the glass is half full.
To the pessimist, the glass is half empty.
To the engineer, the glass is twice as big as it needs to be.