Refractive index retrieval in the UV range using white light spectral interferometry

Continuous refractive index measurement in the UV spectral region and a small part of the Vis region (up to 520 nm) is performed by using white light spectral interferometry. The main limitations of operating in this region are the high dispersion and high absorption. The problems derived from high dispersion are overcome taking the data in several shots, that is, recording several interferograms that must be partially overlapped. Whereas, high absorbers require the use of thinner samples, while still keeping a precise measurement of the sample width. We show the capacity of the technique with well characterized reference materials such as BK7, quartz and deionised water.