Accurate wavelength calibration in the near-infrared for multielement analysis without the need for reference spectra

A new technique has been developed for an instant, precise, and accurate wavelength calibration over a wide pixel array for simultaneous, multielement spectral analysis based on an inverse numerical solution to the grating dispersion function. This technique is applicable to multielement analytical applications such as laser-induced breakdown spectroscopy (LIBS), particularly when using high-density gratings in the upper visible and in the near-infrared, where nonmetallic elements are detected. This application overcomes the need to use reference spectra for each window of observation and is tested on a commercially available LIBS instrument.