Remote-Raman Spectroscopy at Intermediate Ranges Using Low-Power cw Lasers

  title={Remote-Raman Spectroscopy at Intermediate Ranges Using Low-Power cw Lasers},
  author={S. Michael Angel and Thomas J. Kulp and Thomas M. Vess},
  journal={Applied Spectroscopy},
  pages={1085 - 1091}
A portable Raman system is described that has been developed for line-of-site spectral measurements of remotely located samples at intermediate ranges. Raman spectra were measured at distances up to 20 m with the use of a 40-mm-diameter collection optic (f/500) and at 16.7 m with a 22-mm-diameter collection optic (f/750). In all cases, low-power cw lasers were used with powers ranging from 23 to 100 mW. The system consists of a small f/4 image-corrected spectrograph with a liquid-nitrogen… 
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