We consider now the simplest case of a composite detector. It will be an incoherent composition of two simple ones. Thus we will take:

** Remark** Notice that if , then coherent and incoherent
compositions are indistinguishable, as in this case, with
we have that

For we have now the formula:

and to compute the complex amplitudes we will use the Laplace transform method as in the case of one detector. To this end one applies from the left and from the right to Eq. (11) and solves the resulting system of two linear equations to obtain:

where we used the notation

and where stands for

The probability density is then given by

where is the inverse Fourier transform

of

By the Parseval formula we have that is given by:

Thu Feb 22 09:58:31 MET 1996