Errors in the refractive indices of solids measured using a 45 degrees angle-of-incidence technique

By measuring the ratio of p- to s-polarized light intensities reflected at an angle of incidence of 45 degrees from a transparent solid, the refractiv e index of that solid can be determined. The critical factors affecting the accuracy of the refractive index measurement using this technique are disc ussed. The extension of this technique to materials which are weakly absorb ing, or that have non-ideal surfaces, is also discussed and the errors that arise from the neglect of these effects are quantified.