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The specular image only shows the light reflected by the surface of the glossy cylinder,
allowing an easy analysis of the paper gloss. In this example, a narrow shine band is
extracted. The diffuse image only contains the information coming from the scattered
light from the volume.
5.2.
Interaction of light with hair
When polarized light illuminated a hair tress, it interacts in such a way that three
different types of light are observed:
The first reflection (also called
shine
) is a white polarized surface reflection. It
carries the same polarization as the incident light.
The second reflection (also called
chroma
) is a colorful polarized reflection
coming from the bottom surface of hair.
The diffused light (hair color) consists of unpolarized light coming from the
internal scattering.
Light scattering in a human hair fiber
(Simple model)
Hair Cuticle
Hair
Cortex
Incident light
First reflection
(shine)
Diffused light
Diffused light
First reflection
(
shine
)
Second reflection
(
chroma
)
Diffused light
Second reflection
(chroma)