DIN EN 4731:2018 pdf free.Aerospace series -Spectral quality of LED luminaires used with photoluminescent marking systems.
4 Spectraiquality
4.1 Method for determination of Ce for a luminaire
4.1.1 Single colour LED luminaires
The excitation coefficient Ce for single colour LED luminaires shah be determrned according to the following steps:
1. Record the luminaire’s spectral irradiance EA(A) in steps of 1 nanometer (1 nrn) in a steady state condition with a spectrometer in the wavelength range of 360 nm to 780 nm and an optical bandwidth not greater than 5 nm;
2. Calculate the photometrically weighted spectral irradiance EJA(2) by multiplying the spectral irradiance EA(2) and photopic luminosity function V(A) in steps of every nanometer;
3. Calculate the approximated weighted spectral excitation irradiance £4A(A) by multiplying the spectral irradiance EA(A) and the approximated excitation spectrum A 2(A) in steps of every nanometer;
4. Calculate the photometrically weighted irradiance EVwithin in the range of 360 nm to 780 nm;
5. Calculate the approximated weighted excitation irradiance EA within the range of 360 nm to
490 nm;
6. Calculate Ce by dividing the approximated weighted excitation irradiance EA by the sum of EA and photometrically weighted irradiance EV.
4.1.2 Multiple colour LED luminaires
The excitation coefficient Ce for multiple colour LED Luminaires shall be determined according to the following steps:
1. Define the parameters of a colour scenario that is dedicated to charging photoluminescent products;
2. Record the luminaire’s spectral irradiance EA(2) in steps of 1 nanometer (1 nm) with the luminaire set to the colour scenario defined per step 1 in a steady state condition with a spectrometer in the wavelength range of 360 nm to 780 nm and an optical bandwidth not greater than 5 nm;
3. Calculate the photometrically weighted spectral irradiance EVA(A) by multiplying the spectral irradiance EA(A) and photopic luminosity function V(A) in steps of every nanometer;
4. Calculate the approximated weighted spectral excitation irradiance EAA(A) by multiplying the spectral irradiance EA(A) and the approximated excitation spectrum AA(A) in steps of every nanometer;
5. Calculate the photometrically weighted irradiance EVwithin in the range of 360 nm to 780 nm;
6. Calculate the approximated weighted excitation irradiance EA within the range of 360 nm to 490 nm;
7. Calculate Ce by dividing the approximated weighted excitation irradiance EA by the sum of EA and photometrically weighted irradiance EV.DIN EN 4731 pdf download.