Hyperspectral Imaging
Definition
An imaging technique that captures a full reflectance spectrum (typically hundreds of narrow wavelength bands from UV to near-IR) at every pixel of an image, producing a three-dimensional data cube analysed by spectral unmixing algorithms.
- Spectral range
- Typically UV through near-infrared
- Band count
- Hundreds of narrow, contiguous wavelength bands
- Output
- Three-dimensional data cube: two spatial axes plus wavelength
- Analysis method
- Spectral unmixing algorithms
Common questions
What can hyperspectral imaging reveal that ordinary photography cannot?+
Because each pixel carries a full reflectance spectrum rather than three broad color channels, the technique can distinguish materials that look identical to the eye, such as two inks or bloodstains on differently dyed fabric, based on their distinct spectral signatures.
Is hyperspectral imaging destructive to the evidence?+
No, it is a non-contact optical method, which makes it attractive for document and pattern evidence where sampling would damage or alter the item before other tests can be performed.
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