Kubelka-Munk Model
Definition
A diffuse-reflectance theory relating the measured reflectance of a scattering-plus-absorbing layer to its absorption and scattering coefficients; used in forensic paint and ink spectrophotometry.
- Type
- Diffuse-reflectance theory
- Relates
- Reflectance to absorption and scattering coefficients
- Applied to
- Forensic paint and ink spectrophotometry
- Layer assumption
- Scattering-plus-absorbing layer
Common questions
Why not just compare raw reflectance spectra of paint or ink directly?+
Raw reflectance mixes absorption and scattering effects together, so two samples with the same colorant but different particle size or layer thickness can look different; the Kubelka-Munk transform separates out the absorption behaviour that actually reflects composition.
What is a limitation of applying the Kubelka-Munk model to real evidence?+
It assumes a diffusely scattering, optically homogeneous layer, an assumption that breaks down for glossy, layered, or very thin coatings, so results need care when the sample departs from those conditions.
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