Detection of Defect on Navel Orange Using Hyperspectral Reflectance Image
A hyperspectral imaging system for detecting defect on navel orange was demonstrated. The hyperspectral imaging system, which was a line-scan imaging system, consisted of a hyperspectral camera, a halogen lighting unit, a computer and a translation stage. The imaging system operated from 400 to 1000nm. Principal component analysis (PCA) was performed using the hyperspectral images data (from 500 to 700nm); 2nd principal component (PC) image exhibited differential responses between normal and defect spots on the surface of navel orange. The combined use of the PC-2 images demonstrated the detection of defect spots with minimal false positives. Based on the PC-2 weighing coefficients, the dominant wavelengths were 528,529,530,673,674 and 675nm. This research demonstrated the potential of multispectral image for online applications for detection of defect on navel oranges.
Jun Hu and Qi Luo
J. Li et al., "Detection of Defect on Navel Orange Using Hyperspectral Reflectance Image", Advanced Materials Research, Vol. 320, pp. 569-573, 2011