STF for pushbroom spectral imaging

From Optical Imaging and Spectroscopy (Wiley - OSA 2009)
By David J. Brady
www.opticalimaging.org
Figure 10.47

stf for pushbroom spectrometer
LoF=Lambda/F
sW slit width
SI units

sW=10^(-4);Delta=10^(-5);fN=2;LoF=10^(-4);lambda=10^(-6);

H[u_]:=(2/Pi) Re[ArcCos[Abs[u]]-Abs[u] Sqrt[1-u^2]];

STF[u_,w_]:=Sinc[sW*(u-w*LoF)]*Sinc[w*LoF*Delta]*H[w*LoF*lambda/fN];

Plot[STF[u,0],{u,0,10^5},PlotRange->All]

Plot[STF[0,w],{w,0,10^9},PlotRange->All]

DensityPlot[STF[10^3*u,10^9*w],{u,-500,500},{w,-10,10},PlotRange->All,PlotPoints->200,ColorFunction->Function[{dt,tl,z},GrayLevel[z]],
FrameLabel->{ u , w}]