s_humanSafetyLuminance

Sometimes we only have a meter to measure the luminance of a light. If the light is monochromatic, then we can still calculate the safety function by converting the monochrome light luminance to radiance.

An example is in here. For more documentation see s_humanSafety.

See also s_humanSafety

Contents

Start with a monochromatic light luminance

% Suppose we measure a monochromatic source and it has these parameters
lum     = 200;     % Luminance of the monochromatic source
thisWave    = 405;    % Mean wavelength of the monochromatic source
dLambda = 10;     % Spectral band width

% We convert the luminance to energy
% watts/sr/nm/m2
[radiance,wave] = ieLuminance2Radiance(lum,thisWave,'sd',dLambda);

% Now read the hazard function (Actinic) of the safety standard.  For more
% information read the comments in s_humanSafety.
fname = which('Actinic.mat');
Actinic = ieReadSpectra(fname,wave);

% Convert radiance to irradiance and calculate the hazard for 1 sec
% duration
duration = 1;                  % Seconds
hazardEnergy = dot(Actinic,radiance*pi) * dLambda * duration;

% Convert the hazard energy into maximum daily allowable exposure in
% minutes using the formula from the standard.
fprintf('Maximum exposure duration per eight hours:  %f (min)\n',(30/hazardEnergy)/60)

Maximum exposure duration per eight hours:  5.056498 (min)

END

Published with MATLAB® R2024a