We present a simple method! to reconstruct the wave function psi(x) describ
ing the transverse center-of-mass motion of an atomic beam. Our method is b
ased on a dispersive interaction between a classical electromagnetic field
and two-level atoms. Behind the interaction region the atomic position dist
ributions are detected. These position distributions allow us to reconstruc
t the phase of psi(x) due to the phase information contained in interferenc
e terms of the form psi(x)psi*(x + Delta x). Moreover, the influence of sev
eral experimental parameters on the reconstruction quality is studied numer
ically.