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replacement for fresnel integral.
Try this:
function E = rectan(amm,bmm,Wmm,smm,Mask2Sensor,lambda,t)
a = amm*sqrt(2/(lambda*Mask2Sensor));
b = bmm *sqrt(2/(lambda* Mask2Sensor));
W = Wmm*sqrt(2/(lambda*Mask2Sensor));
s = smm*sqrt(2/(lambda*Mask2Sensor));
[Cu2, Su2] = fcs(a:s:W+a);
[Cu1, Su1] = fcs(-a:s:W-a);
[Cv2, Sv2] = fcs(b:s:W+b);
[Cv1, Sv1] = fcs(-b:s:W-b);
% Cu2 = mfun('FresnelC',a:s:W+a);
% Cu1 = mfun('FresnelC',-a:s:W-a);
% Su2 = mfun('FresnelS',a:s:W+a);
% Su1 = mfun('FresnelS',-a:s:W-a);
% Cv2 = mfun('FresnelC',b:s:W+b);
% Cv1 = mfun('FresnelC',-b:s:W-b);
% Sv2 = mfun('FresnelS',b:s:W+b);
% Sv1 = mfun('FresnelS',-b:s:W-b);
A = (Cu1-Cu2).^2+(Su1-Su2).^2;
B = (Cv1-Cv2).^2+(Sv1-Sv2).^2;
B = B';A = A';
n = length(B);B = repmat(B(:,1),1,n);
A = repmat(A(:,1),1,n);A = (A)';
D = B*A;
D = t*D/max(D(:));
m = 2*fix(((2*W)/s)/2);
E = zeros(m+1,m+1);
for q = 1:(m/2+1)
for p = 1:(m/2+1)
E(((m/2)+2-p),(q+(m/2))) = D(p,q);
end
end
for q = (m+1):-1:((m/2)+2)
for p = 1:((m/2)+1)
E(p,(-q+2+m)) = E(p, q);
end
end
for q = 1:(m+1)
for p = 1:(m/2)
E((-p+2+m),q) = E(p,q);
end
end
y = -W:s:W;
ymm = y*sqrt((lambda*Mask2Sensor)/2);
imagesc(ymm,ymm,E,[0 1]);colormap(gray);
