How Did We Come to On-Line NIR Imaging

An example of this occurred during the 1990s, when a NIR imager was developed for canning companies that could detect stone pieces in peach halves. In the canning plant, when the peaches are pitted automatically the stone may be broken by the saw of the stoner a sorting step is then required to remove the residual stone pieces. The RGB cameras proved to be totally ineffective for this purpose as the stone contaminants were located in a concave area, generating shadows. When the task was performed manually it proved to be especially tedious as the colors of the stone and irmer flesh were very similar. However, as the water content of 

When bruise causes damage to the internal structure of the apple flesh, the cells are destroyed and the cytoplasm invades the intercellular space this leads to a change in diffusion and absorption coefficients, creating easily detected black spots. 

In addition to differences in scattering, NIR lighting/imaging also allows advantage to be taken of more subtle chemical differences between objects, although in this case more sophisticated systems based on multispectral or hyperspectral imaging are required. 

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