/usr/share/psychtoolbox-3/PsychRadiometric/TrolandsToRetIrradiance.m is in psychtoolbox-3-common 3.0.14.20170103+git6-g605ff5c.dfsg1-1build1.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 | function [irradianceWattsPerUm2, irradianceS] =...
TrolandsToRetIrradiance(relativeSpectrum, relativeSpectrumS, trolands, photopic, species, source)
% [radianceWattsPerM2Sr, irradianceS] =...
% TrolandsToRetIrradiance(relativeSpectrum, relativeSpectrumS, trolands, [photopic], [species], [source])
%
% The assumption underlying this routine is that the relative spectrum of a light
% is available, as well as the retinal illuminance in trolands.
%
% The routine computes the irradiance (watts/um^2-wlinterval) from the relative spectrum
% (relative power, not relative quanta) and the number of trolands.
%
% See Wyszecki and Stiles, 1982, p. 103 for the conversions.
%
% Input variables: relativeSpectrum - the relative power as a function of wavelength.
% relativeSpectrumS - the wavelength sampling information for the relativeSpectrum.
% trolands - the number of trolands.
% photopic - what kind of trolands: 'Photopic' (Default), 'JuddVos', 'Scotopic'.
% species - what species determins eye length: 'Human' (Default), 'Monkey'.
% source - source for eye length estimate, passed directly to EyeLength and inherits its default.
%
% 07/18/03 dhb Wrote it.
% 1/26/04 ly, dhb Fix JuddVos path through switch.
% 7/16/13 dhb Comment and code cleaning, minor.
% Fill in default values
if (nargin < 4 || isempty(photopic))
photopic = 'Photopic';
end
if (nargin < 5 || isempty(species))
species = 'Human';
end
S = relativeSpectrumS;
% Load appropriate V_lambda for phot/scot
switch (photopic)
case 'Photopic'
load T_xyz1931;
T_vLambda = SplineCmf(S_xyz1931,T_xyz1931(2,:),S);
clear T_xyz1931 S_xyz1931
magicFactor = 2.242e12;
case 'JuddVos'
load T_xyzJuddVos;
T_vLambda = SplineCmf(S_xyzJuddVos,T_xyzJuddVos(2,:),S);
clear T_JuddVos S_JuddVos
magicFactor = 2.242e12;
case 'Scotopic'
load T_rods;
T_vLambda = SplineCmf(S_rods,T_rods,S);
magicFactor = 5.581e12;
end
% Convert relative spectrum into watts/deg^2 on retina.
% We know that trolands = k*(T_vLambda*relativeSpectrum)*magicFactor,
% were k is a factor that puts the relative spectrum into units of
% retinal irradiance in watts/deg^2-wlinterval
k = trolands/(T_vLambda*relativeSpectrum*magicFactor);
irradianceDeg2 = k*relativeSpectrum;
% Convert to units of um2
eyeLengthMM = EyeLength(species,source);
mmPerDeg = DegreesToRetinalMM(1,eyeLengthMM);
mm2PerDeg2 = mmPerDeg^2;
irradianceMM2 = irradianceDeg2/mm2PerDeg2;
irradianceWattsPerUm2 = irradianceMM2*1e-6;
irradianceS = S;
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