Optical images with spectral resolution in the order of 10 nanometers are called hyperspectral images.
Hyperspectral sensors, i.e. imaging spectrometers, mounted on different space platforms (like airplanes, UAV and satellites), simultaneously image the target region in the ultraviolet, visible, near-infrared and mid-infrared bands of the electromagnetic spectrum with dozens to hundreds of continuous and subdivided spectral bands.
While obtaining the spatial information of earth surface, hyperspectral images also obtain the spectral information. Compared with multispectral Remote sensing images, hyperspectral images not only greatly improve the information richness, but also provide a more reasonable and effective analysis and processing of this type of spectral data in processing technology.
According to the different performance of different substances in different bands of spectral signals, a curve about the spectral bands and spectral values can be drawn. According to the difference of the curves, we can classify different substances in hyperspectral images.