On the problem of phase from intensity measurements*

Abstract

An approach is presented for computing from intensity measurements the spatial (relative) phase of a one-dimensional optical field across an aperture. Both single measurements in the focal plane and simultaneous measurements in the aperture and focal planes are considered. In each case, the reason for nonuniqueness of the solutions is presented and interpreted. Methods for removing the ambiguity of the apparent phase solution are examined and are shown to be, in general, physically unjustified. Thus for arbitrary fields none of the schemes presented can practically be used to obtain phase from intensity measurements.