@article{chen02a,
  author = {Yin-Chu Chen and Sean J. Kirkpatrick and Scott A. Prahl},
  title = {Refractive Index Measurements with a {R}ayleigh Interferometer},
  journal = {Proceedings of the Oregon Academy of Science},
  volume = {38},
  pages = {44},
  year = {2002 abstract only},
  abstract = {Optical interferometry expoits the interference of light by creating the fringe patterns that result from small optical changes. Interferometers are sensitive to external influences such as vibrations or refractive-index fluctuations of the optical media. A Rayleigh interferometer was constructed that consists of two slits that create two separate beams. These beams are recombined to form an interference pattern that is expanded onto a video camera for visualization. Mirrored prisms and mirrors were used to increase the physical separation between the two beams. Samples were placed only in the upper portion of one beam, thereby altering only the upper portion of the interference or fringe pattern. The lower portion of the fringe pattern served as a reference. Small changes in the refractive index of the sample were measured by comparing the upper and lower fringe patterns. Two methods were used to measure shifts between the upper and lower fringe patterns. One method used a Fourier transform and the other method used a least squares technique. The robustness and accuracy of both methods is presented.},
}