The design, fabrication, and calibration of a fiber filter spectrometer

A fiber filter spectrometer (FFS) is a novel imaging spectrometer design concept which uses the proximity filter method to create small, lightweight, and cost effective instruments with no detectable spectral crosstalk. An FFS sensor is created by coating the ends of a fiber optic image guide (FIG) with a spectral filter, the FIG is then coupled to a detector array. Using the FIG as the spectral filter substrate reduces the optical crosstalk to the point that it is inconsequential. This work describes the modeling, fabrication, and calibration of a hyperspectral FFS sensor. The image and spectral quality performance metrics are successfully predicted by the FFS model. The laboratory calibration of the instrument validates that the FIG has no substantial impact on the instrument image quality and spectral performance. The FFS concept eliminates the potential for spectral crosstalk and provides the advantages of a less complex imaging spectrometer instrument design with low mass and volume.