I am trying to find the efficiency (electrical power in vs light power power out) to work out efficiency of high power LED (aka emitter) so that I can work out waste power dissipated.

So far not found anything in google - can you help?

That is your challenge for tonight!

[Edited on 21/11/08 by 02GF74]

not more homework

LEDs are usually quoted in candela - the amount of light in a cone. It makes them sound better because of the narrow beam they produce. Candelas are the number of lumens per steridian, a dimensionless unit of a cone. I believe there are 12 PI steradians in a sphere. In any case, lumens - the amount of light, is a form of power and Wikipedia or google will tell you how many lumens there are in a watt. About 600 or so. A bit of maths will therefore convert candelas to watts of light emitted. The rest of the power put into the LED will be heat.

special brew + homework = very low candela + hot sweats = low efficiency

Tee hee not very BRIGHT

[Edited on 21/11/08 by Bigheppy]

is this of any usefullness?

http://en.wikipedia.org/wiki/LED#Efficiency_and_operational_parameters

Vodka - im out!

this has been on my mind too recently as i need to make a VERY bright torch. I was torn between a non-roadlegal 100w headlight bulb running off a car battery, or maybe a zenon bulb.

No idea about efficiency though!

quote:

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Originally posted by JoelP
this has been on my mind too recently as i need to make a VERY bright torch. I was torn between a non-roadlegal 100w headlight bulb running off a car battery, or maybe a zenon bulb.

No idea about efficiency though!

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