Device and method for measuring complex reflectance using a light source for generating a light beam with known polarization state, a lens for focusing the beam onto a sample surface such that various rays within the focused beam create a spread of angles of incidence .theta., a waveplate for retarding one polarization state of the beam, a polarizer for generating interference between beam polarization states, and a detector with a two dimensional array of detector elements for generating intensity signals in response to the beam, wherein each detector element corresponds to a unique angle of incidence .theta. and azimuthal angle .phi. of the reflected beam. A processor calculates magnitude and phase values for the reflected beam by using the intensity signals corresponding to at least one incident angle .theta. and a plurality of azimuthal angles .phi. within the at least one incident angle .theta. sufficient to enable a meaningful Fourier analysis thereof.