Calibration of Imaging Spectrometry System for Inspection of Contaminated Poultry Carcasses

Abstract

A method to calibrate a hyperspectral imaging system had been demonstrated. Themethod consists of a modified geometric control point correction to remove smile and keystoneeffect from the system and applying both wavelength and distance calibrations to reduce thewavelength and distance errors to less than 1 pixel value. Next, a pixel-by-pixel percentreflectance calibration was performed at all wavelengths with dark current and 99% reflectancecalibration-panel measurements, and results were verified with measurements on a certifiedgradient Spectralon panel with nominal values ranging from 12% to 99%. Results indicate thesystem is capable of calibrating the hyperspectral system across the entire spectral range of thedetector, but errors increase significantly below 420 nm and above 840 nm. Further researchshould be performed to evaluate the stability of the calibration over time, and techniques mustbe developed to implement the calibration for real-time analysis.