Lumens and photon flux density

Thread starter DMS-Aberdeen
Start date Aug 20, 2012
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Density Flux Flux density Photon

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Calculating photon flux density from lumens produced by a fluorescent tube is not straightforward. It requires knowledge of the spectral power distribution (SPD) of the light and its radiation pattern. The SPD can typically be obtained, while the radiation pattern may need to be estimated. Without these specifics, an accurate calculation cannot be made. Understanding these factors is essential for precise measurements of photon flux density.

Aug 20, 2012

DMS-Aberdeen

Is there a simple way of calculating photon flux density from the lumens produced by a fluorescent tube?

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Aug 20, 2012

Rap

Not exactly. You need to know the spectrum (spectral power distribution, or SPD) of the fluorescent light, and the radiation pattern. The SPD should be available, and you could estimate the radiation pattern.

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