EIGENVALUE FORMULATION OF INVERSE THEORY OF SCALAR DIFFRACTION.

The Shewell-Wolf inverse theory of scalar diffraction treated as an eigenvalue problem is formulated and some mathematical and physical consequences of this formalism are discussed. The relations between Slepian, Pollack and Landau problem and the inverse theory of diffraction are analysed. The additive model of noise used in Slepian et al. problem is adapted to scalar theory of diffraction.