Masonry
Stone does not pass much light and the reflection depends
on the surface coarseness. For this reason, HORIBA Gloss
Checkers are used to measure surface finish, polish,
scratch and corrosion besides glossiness.
Painted surface
The figure below shows how light reflects off a coated
surface. Incident light is separated into
1) Specular reflection at the coating surface,
2) Scattered diffuse reflection due to coating surface
imperfections and
3) Random diffuse reflection off pigments below the
coating surface.
The first 2 types of refection are independent of the paint
color and its absorbing property and depend on the
refraction index and surface uniformity. Intralayer diffuse
reflection, on the other hand, is subject to absorption and
the color, brightness, and other properties have effects.
This complexity of any painted surface makes it important to
consider the tone and clarity of specular reflection and not
just its intensity.
Floor tile
Office and store floors are periodically cleaned and waxed
to maintain beauty. But visually assessing how clean the
floor leaves room for ambiguity. Horiba Gloss Checkers are
being widely used as a tool to provide objective, more
scientific means to floor maintenance. The figures below
describe reflection off floor tiles.
Paper
Papers typically have a simple single layer structure as in
the figure below, but coated paper such as high gloss-paper
have a 2-layer structure having a complex reflection
pattern. Some paper with very high retroreflection and/or
intralayer diffuse reflection properties gives counterintuitive
readings. Thickness and material of the coating affects
measurement also; however, HORIBA Gloss Checkers
have high data reproducibility and stability. They can be
used to detect irregularities of the same paper type or in
finding deviations from a standard.
Specular
reflection
Diffuse
reflection
Floor tile
Incident light
Specular
reflection
Diffuse
reflection
Polished finish
Incident light
Diffuse
reflection
Rough finish
Paper
Waxed floor tile
Specular
reflection
Retroreflection
Diffuse
reflection
Wax
Surface
diffuse
reflection
Intralayer diffuse
reflection
Painting film
Pigments
Specular
reflection
Surface
diffuse
reflection
Retroreflection
Coating
Intralayer diffuse reflection
2-Layer structure
of coated paper
Specular
reflection
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