The hyperspectral imaging and multispectral imaging brings information to light. Both technologies uses the spatial and wavelength-separated detection in different electromagnetic wavelength-ranges (spectrum).
| ultraviolet light (UV) | spectral range 50 nm – 400 nm |
|---|---|
| visual light | spectral range 400 nm – 750 nm |
| near infrared light | spectral range 750 nm – 2500 nm |
| mid-infrared (MIR) | spectral range 2500 nm – 10000 nm |
The difference between multispectral and hyperspectral imaging is the number of the acquired spectral points. For a ‚real‘ hyperspectral imaging 100 spectral points should be acquired at least. Hyperspectral systems works in most cases – due to a line-wise scanning – as pushbroom imager, whereas the most multispectral imager record the whole image in one shot. The spectrum is then generated by the propagation of light through different optical filters (‚multichannel‘), sub-pixel-structures (‚Filter-on-Chip‘) or special prisms.
In accordance to the detector technolgy, hyperspectral and multispectral cameras will be often differentiated in respect to the usable wavelength ranges:
| UV |
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|---|---|
| VNIS (abbrev.: VIS-NIR) |
|
| NIR |
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| SWIR (abbrev.: short wave infrared) |
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| MIR |
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Perceiving more than the eye can see.
Fraunhofer Institute for Material and Beam Technology IWS