Apodization truncation error

Apodization can be used to artificially broaden the narrower resonances in a spectrum and thus to remove the visually disturbing aesthetic caused by truncation error. 

Now, let us consider phase errors. As already pointed out, an error arises when the true origin of the interferogram is missed by a small path difference b <. As (Fig. 40 a) where Js is the sampling interval. This error is called a linear phase error because 2nvB means an erroneous phase shift in the interferogram function, which is linear with respect to the wave number v. Including the effects of truncation and apodization, we obteiin for the cosine transform of the double-sided interferogram with a phase error e approximately ss.es.vo) ... 

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