Laser-induced breakdown spectroscopy; remote LIBS; standoff LIBS; spatial heterodyne spectrometer; remote spectroscopy;IN-SITU ANALYSIS; RAMAN-SPECTROSCOPY; QUANTITATIVE-ANALYSIS; SOLID-SURFACES; SAMPLES; PLATFORM; PLASMA; SENSOR; PROBE

A spatial heterodyne spectrometer (SHS) is described for standoff laser-induced breakdown spectroscopy (LIBS) measurements. The spatial heterodyne LIBS spectrometer (SHLS) is a diffraction grating based interferometer with no moving parts that offers a very large field of view, high light throughput, and high spectral resolution in a small package. The field of view of the SHLS spectrometer is shown to be similar to 1 degrees in standoff LIBS measurements. In the SHLS system described here, the collection aperture was defined by the 10mm diffraction gratings in the SHS and standoff LIBS measurements were made up to 20m with no additional collection optics, corresponding to a collection solid angle of 0.2 mu sr, or f/2000, and also using a small telescope to increase the collection efficiency. The use of a microphone was demonstrated to rapidly optimize laser focus for 20m standoff LIBS measurements.