A ray-tracing analysis of cat’s-eye retroreflectors for use in active open-path Fourier-transform-infrared (OP/FT-IR) spectrometry and the results of testing <i>f</i>/0.5 and <i>f</i>/1.75 cat’s-eye retroreflectors built in our laboratory with a commercial active OP/FT-IR spectrometer are presented. The ray-tracing model is based on the optical characteristics of a commercial single-telescope monostatic OP/FT-IR spectrometer and explores trends in cat’s-eye behavior in practical but rigorous field conditions encountered during transportable outdoor use. All mirrors modeled are paraboloids for which the focal ratios of the primary mirror are <i>f</i>/0.5, <i>f</i>/1.75, and <i>f</i>/3. The effect of the focal ratio of the primary mirror, the focal length of the secondary mirror, and the off-axis alignment of the primary and the secondary mirror have been evaluated as a function of path length, including variable input-beam divergence, between the spectrometer and the cat’s-eye. The paraboloidal mirrors comprising the primary and secondary of the cat’s-eye retroreflectors tested were made in our laboratory by spin casting liquid epoxy-graphite composite mixtures followed by <i>in situ</i> polymerization with no postpolishing.
© 2002 Optical Society of America
Robert L. Richardson and Peter R. Griffiths, "Design and Performance Considerations of Cat’s-Eye Retroreflectors for Use in Open-Path Fourier-Transform-Infrared Spectrometry," Appl. Opt. 41, 6332-6340 (2002)