function y=W1(lambda);
% 2005.12
% Emmanuel Boss
% emmanuel.boss@maine.edu
% School of Marine Sciences, University of Maine, USA
%
% Calculates the wavelength weighting function for Eco-type sensors.
%
% INPUT
% Incident wave wavenumber                      (lambda) [nm] 
% NB: the LED output and filter wavelengths response are loaded from the files LED_spectra
% (computed by us for our sensor) and Wetlabs (where the receiver filters
% are). Photodiode responsivity curve is a digitazation of a curve found on
% the WWW at http://beammeasurement.mellesgriot.com/tut_photo_det.asp

% OUTPUT
% integrand value                               (y)

%LED output spectra. 
%center wavelength.
mean=650;
%standard deviation around the wavelength
sd=10;

y=exp(-(lambda-mean).^2./(2*sd^2));

