Generalized gamma distribution

The centre wavelength is the power-weighted mean wavelength:

$\lambda _{c}={\frac {1}{P_{total}}}\int p(\lambda )\lambda \,d\lambda$

And the total power is:

$P_{total}=\int p(\lambda )d\lambda$

where $p(\lambda )$ is the power spectral density, for example in W/nm.

The above integrals theoretically extend over the entire spectrum, however it is usually sufficient to perform the integral over the spectrum where the spectral density $p(\lambda )$ is higher than a fraction of its maximum.

See also

• peak wavelength
• dominant wavelength

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