Evaluation and characterization of a laboratory VNIR spectrometer for use in the calibration of field radiometers

Recently, NASA Goddard Space Flight Center Biospheric Science Laboratory (Code 618) Field Calibration Lab acquired a new laboratory spectrometer system. With the intention of becoming a standard transfer spectrometer for the lab, the system is comprised of 4 separate units covering the spectral range of 185-2500nm. The Field Calibration Lab has been serving the Earth Sciences Division and specializing in spectral radiometric measurements with Field spectrometers and radiometers. This new system was acquired as a complimentary lab standard to the fieldwork and other transfer work performed by the laboratory’s field spectrometer working standard. This work details the initial lab characterizations of two of the four units that cover the spectral range of 185-740nm and 655-1100nm respectively, with a narrow-band LED-driven light source and a standalone silicon reference detector. The results will be discussed, with some comparisons to a widely used commercially available field spectrometer system. We have found that the new laboratory system can be comparable to the historically used field spectrometer in most circumstances, but with key differences in spectral resolution and sensitivity. As a result, the new system has potential use as an absolute transfer standard, in characterization of fine spectral features and exploration of low-level light sources and environments.