Determining Optical Material Parameters With Motion in Structured Illumination

The broad need for determining the optical properties of thin films in a multitude of applications is usually served by ellipsometry. Practical application of ellipsometry generally requires prior constraints, typically in the form of a frequency-dependent model. To provide for a suitable solution of the inverse problem, where film parameters are determined from a set of optical measurements. We present motion in structured illumination as a means to obtain additional information and hence avoid the need for a material response model. Using this approach, inversion for multiple parameters at each wavelength becomes possible, and in a mutual information sense, this is achieved by taking intensity measurements at a known set of displacements in a cavity.