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function [val_UWattsPerCm2,limit_UWattsPerCm2] = ISO2007MPEComputeType1ContinuousAntConvrgUnweightedValue(S,irradiance_UWattsPerCm2,stimulusDurationSecs)
% [val_UWattsPerCm2,limit_UWattsPerCm2] = ISO2007MPEComputeType1ContinuousAntConvrgUnweightedValue(S,irradiance_uWattsPerCm2,stimulusDurationSecs)
%
% Compute the unweighted radiation for anterior segment convergent beam value, for Type 1 instruments as given on page 8, Table 2,
% 5.4.1.5. This limit applies only to convergent beams, whatever they are. I'm guessing this is what a Maxwellian view produces,
% however, as in that case the beam is brought to a waist inside the eye. In this case, the limit applies to the irradiance
% at the beam waist over the 1 mm diameter aperture with the highest irradiance.
%
% Unlike all the other routines in this suite, the key quantity is probably not best passed as stimulus radiance. Rather, for
% this type of optical system, the relevant irradiance should be measured directly.
%
% NOTE: This routine has not been tested, since I (DHB) don't have any instrument currently that produces the relevant type of
% stimulus. I added it as a placeholder for convenience. There is an error statement to keep it from being used
% until it is tested.
%
% Input spectrum is radiance in units of UWatts/[m2-wlinterval].
%
% Also return the exposure limit for this quantity.
%
% See page 6 for a definition of a Type 1 instrument. As far as I can tell, the key
% criterion is that it doesn't put out more light that exceeds the Type 1 limits.
%
% If the exposure time is longer than 2 hours the specified limits should be reduced by
% 1/exposureDuration in hours. This routine implements that adjustment for its returned
% limit value. It does not implement a further reduction of of the limit (by a factor of 2)
% for microscopes and endoilluminators.
%
% ****************************************************************************
% IMPORTANT: Before using the ISO2007MPE routines, please see the notes on usage
% and responsibility in PsychISO2007MPE/Contents.m (type "help PsychISO2007MPE"
% at the Matlab prompt.
% ****************************************************************************
%
% 6/28/13 dhb Wrote it.
%% Error statement to indicate draft status of this routine.
fprintf('\tISO2007MPEComputeType1ContinuousAntConvrgUnweightedValue\n');
fprintf('\t\tThis routine has been drafted but not tested. It might\n');
fprintf('\t\tbe correct. Or it might not. Develop a reasonable\n');
fprintf('\t\ttest before using.\n');
error('Not yet ready for use');
%% Specify the limit (from table)
%
% Limit in table is in Watts, we convert to uWatts
% for consistency with the weighted routine.
exposureDurationHours = stimulusDurationSecs/3600;
if (exposureDurationHours <= 2)
limit_UWattsPerCm2 = 4*(10^6);
else
limit_UWattsPerCm2 = 4*(10^6)/(exposureDurationHours/2);
end
%% Get sum betwen 380 and 1200.
wls = SToWls(S);
index = find(wls >= 380 & wls <= 1200);
if (isempty(index))
error('Should not call this routine with no spectral sampling between 380 and 1200');
end
val_UWattsPerCm2 = sum(irradiance_UWattsPerCm2(index));
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