Table 7.

Comparison of calculated photon flux densities $(PF{D}_{\mathit{calc}}$) from Eq. 6 and “approximated” photon flux densities $(PF{D}_{\mathit{approx}}$) using Eq. 8 for four single coloured LEDs and two white light sources

central wavelength	$E_R=1\mathrm{W}{\mathrm{m}}^{-2}$
${\lambda }_c$/ nm	$PF{D}_{\mathit{calc}}$/$\mu \mathrm{mol}{\mathrm{s}}^{-1}{\mathrm{m}}^{-2}$	$PF{D}_{\mathit{approx}}$/$\mu \mathrm{mol}{\mathrm{s}}^{-1}{\mathrm{m}}^{-2}$
425 (violet LED)	3.7	3.6
530 (green LED)	4.4	4.4
550 (white, fluorescent tube)	4.7	4.6
550 (white, LED)	4.6	4.6
600 (amber LED)	4.9	5.0
630 (red LED)	5.3	5.4

For both white light sources, a central wavelength of ${\lambda }_c=550\mathrm{nm}$ was assumed. For the single coloured LEDs, the peak wavelength was set the central wavelength