Abstract

In optics, the intensity, which represents the square of the module of a optical complex field |f(x)|², is the only measurable quantity, but the complex field itself, f(x) = f_r(x) + f_i(x), is more interesting for investigating the source or scatterer as an inverse problem, A modified 180° rotational shearing interferometer¹ with perpendicular polarization in each arm was built for separating the real and imaginary parts of its Fourier spectrum.² The quantities |f_r(x)|² and |F_i(x)|² can be measured experimentally, and their correct signs can be determined through the derivative of the real power spectrum with respect to an optical path difference S introduced into the interferometer experimentally.

© 1990 Optical Society of America