Optical models for colored surfaces

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Optical models
for colored surfaces
Mathieu Hébert
Institut d’Optique – Graduate School
Université Jean Monnet de Saint-Etienne, Master Optique, Image, Vision
2014 - 2015
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1.
The art of shaping light
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Origin of colors
"Physical" or
"chemical" colors ?
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Physical (or structural) colors
Diffraction
Diffusion
(Rayleigh)
Dispersion
Interférences
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Chemical colors
Pigments / colorants
FeO(OH) ochre
CdS Cadmium yellow
Cd(S,Se) cadmium red
…
Carotene
Garance red
Gems
Al2O3 Corindon
Al2O3::Cr rubis
alizarin
Chlorophyll
Glass
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 Absorption
Glass and stained glass
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Nanoparticles in glass
Oxydation of metallic ions creates nanoparticles
spectral absorption due to plasmon resonance
Different colors are obtained with different temperatures of
annealing
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Nanoparticles in glass
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Roman vase, 5th century
Illuminated from inside
© Jacques Lafait, INP
Illuminated from outside
Nanoparticles in glass
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Lusterware
© PhD thesis by Vincent Reillon, INP, 2008
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Lusterware
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Nanoparticle layers appears by
annealing
Under directional light
© PhD thesis by Vincent Reillon, INP, 2008
viewed at 20°
Under diffuse light
viewed at 60°
Laser induced lusterware
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Interferential colors are produced by scanning a layer containing
Ag2+ ions with a Laser
Under directional light
Under diffuse light
 Absorption (plasmon resonance), diffraction, interferences.
© Renée Charrière, Nathalie Destouche, Laboratoire Hubert Curien, 2012
Art painting
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Art Glaze
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Color chart using one pigmented binder, by painter Jean-Pierre Brazs
 Absorption (pigmented layers)
 Diffuse reflection (backing)
 Slight scattering (pigments)
© PhD Thesis by Lionel Simonot, 2003
Art glaze
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Van Eyck (XVth c.)
The Arnolfini portrait, 1434.
Glaze on wood
Art glaze
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Art glaze
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Van Eyck
The Ghent Altarpiece
finished 1432
24 glaze painting panels.
Most influent painting in history of art.
Also most stolen masterpiece
(13 times ! and still one missing…)
Image synthesis at the end
of the Middle Age: wood, stone,
textile, fur, skin, hair, paper, pearls,
gems, metals…
Art glaze
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Art glaze
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Art glaze
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Art glaze
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Multispectral imaging
A technique to study masterpieces
© Pascal Cotte
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Spectra  pigments  original colors
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Simulation of the original Mona Lisa painting from pigment mixtures
detected by multispectral imaging (Mady Elias & Pascal Cotte)
Woodcut print (ukiyo-e)
Hokusai
The great wave of Kanagawa
1828-29
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Hiroshige
Atake under sudden rain
100 view of Edo series
1856-58
Woodcut print (ukiyo-e)
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Wood cut
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Alfonse Maria Mucha
(1896)
Spring
Summer
Automn
Winter
Skin colors in art
Spectral reflectance
of human skin
(Caucasian)
Mona Lisa
without varnish
© M. Elias, P. Cotte
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Photographs
Lippmann process (from 1892)
 Interferences (satding waves)
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Gabriel Lippmann
Nobel Prize in Physics in 1908
Photographs
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Analog photographic films
Film base
Subbing layer
Red light sensitive layer
Green light sensitive layer
Yellow filter
Blue light sensitive layer
UV Filter
Protective layer
 Pure absorption
© wikipedia
Visible light
Analog photographs and prints
Continous tones (contone)
Woodcut prints
Analog photographs
Painting
Discrete tones (halftones)
Engraving
Digital printing
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Printing technologies
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Silkscreen printing (sérigraphie)
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Offset
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Inkjet
Système à jet continu
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Système à la demande
Electrophotography (laserjet)
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Electrophotographie (laserjet)
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Special printing and effects
Guilloches
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Special printing and effects
Custom inks
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Special printing and effects
Fluorescing inks
© Lab. Systèmes Périphériques (EPFL)
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