The USGS has been collaborating closely with the National Institute for Standards and Technology (NIST) and the Mitre Corporation on the development of a full-range hyperspectral microscope to support remote sensing research. Over the past 20 years, hyperspectral microscopy has grown into a robust field of analysis for a number of applications, mostly related to medical diagnostics. Development of a hyperspectral imaging microscope is aimed at material characterization to complement traditional stand-off hyperspectral remote sensing applications. USGS scientists have combined commercial off-the-shelf (COTS) technology along with a tunable laser in order to collect spectral data from 405–2500 nanometers. Hyperspectral imagery (HSI) microscopy allows for target material to be examined at the sub-centimeter spatial scale, and provides a means to collect more than 10,000 spectra from both pure substances and mixtures. The large abundance of spectra allows for a more detailed understanding of the distribution and variability of spectra. This additional information may aid in understanding the variability observed in ground-truth spectra collected from portable spectrometers. Additionally, the datacubes collected can serve as proxies for airborne and spaceborne collected datasets for test and evaluation purposes.
Most hyperspectral reflectance measurements are point samples made on field materials or synoptic, overhead imagery pixels. Imaging spectroscopy at the microscopic level offers the same material and process identification advantages as overhead, imaging spectroscopy. There exists a need in the remote sensing community to characterize materials based on pure spectral reflectance over the full solar-reflected (350–2500 nm) range without the spatial or spectral distortions that are inherent in most imaging applications.