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Candela and photons

  1. Oct 17, 2013 #1
    Hello everyone,

    My issue is regard a conversion from lumens to ~photons or energy at varying wavelengths. I am trying to find a way to determine the amount of energy an led can emit at different wavelengths. I figured because E = (h*c)/λ all I would need is to determine an photon emission. Most of the data sheets give Lm/W and the viewing angle. I know that Cd = Lm /(2π(1-cos(θ/2)), but thats as far as I got. I need a definite way to calculate the theoretical energy being emitted at different wavelengths. If anyone can help me finish what I started or help me discern a better way of find this it would be much appreciated. Also what would I do for wavelength out of the visible spectrum? For most UV or IR leds I have mW/sr @ mA, viewing angle and the basic electrical properties.
  2. jcsd
  3. Oct 17, 2013 #2


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    Last edited: Oct 18, 2013
  4. Oct 17, 2013 #3


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    would you like to fix your link so it gets to the correct page please
    as I have done in the quote of yours :smile:

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