SAMBAHAIR SYSTEM - HAIR VISUAL APPEARANCE ...

SAMBA HAIR SYSTEM
- HAIR VISUAL APPEARANCE
CHARACTERIZATION-
N. Lechocinski,M. Ikeda, P. Clemenceau, S. Breugnot
Bossa Nova Technologies, Venice, CA, USA
CITE Tokyo, March 09

• Bossa Nova Technologies company profile
• Technical background :
• Polarization, Interaction between light and sample, Hair visual appearance
• Hair measurement setup :
• Setup, Images acquired, Angular profiles
• Luster parameter
• Usual luster formulae, issue with polarization, new luster formula
• Experimental results
• On black, red and blond hair
• Color analysis allows full understanding of light scattering
• Comparison with goniophotometry
• Video
• Conclusion
Table of contents

� LLC Created in 2002. Located in California, USA
� Team of engineers and scientists specialized in optics, electronics,
imaging and software development
� Bossa Nova Technologies manufactures sensors, non destructive testing
systems, and visual appearance measurement systems
Systems for the cosmetic industry
SAMBA
Face System
SAMBA
Hair System
Company profile

Light can be characterized by three fundamental properties :
• its intensity
• its spectrum (visible spectrum (color), also infrared, UV, …)
• its polarization
Technical background: Polarization of light
Related to amplitude of light vibration
Related to frequency/wavelength of light vibration
Related to orientation of light vibration

Light source
Vertical Polarizer
Pigments
Sample (Skin, hair…)
DIFFUSED/SCATTERED LIGHT
Depolarized Light
Polarization is a tool to study light scattering.
Technical background: light scattering
It allows to separate reflections (specular light) from diffusion.
We use it to characterize the visual appearance of hair.
SPECULAR
Polarization is
preserved

Technical background: interaction of light with hair fibers
POLARIZED
Chroma= Colored band
coming from the internal
reflection
Shine= White band
coming from the
reflection on the surface
UNPOLARIZED
Diffused light: uniform
background color coming
from internal scattering
Visual appearance of hair can be measured by measuring the light scattering

The setup used is based on three main elements:
• A polarized illumination (2)
• A cylinder on which the sample is positioned (3)
• A polarization camera (1)
Hair System setup
Polarized illumination and polarization camera allow
measuring independently reflections and diffusion.
Cylinder is used to record angular distribution profiles
The cylinder also reproduces the human head
curvature
SAMBA Hair System is a visual setup based on polarization imaging

Hair System setup
Each section on the image
corresponds to an angle of
incidence on the cylinder.
Using a cylinder allows recording
all angles on a single image,
without moving the cylinder.
This is a visual setup.

Polarization imaging physically separates reflections from diffusion on a complete
hair tress in just seconds.
Intensity image
(seen by the eye)
Specular image
(reflections only)
= +
Acquisition of the images (data)
Diffused image
(internal scattering)
Diffused light and reflections
are physically separated
without using fits or
mathematical decomposition.
As reflections are
responsible of the luster
sensation, polarization is a
useful tool to help quantify
luster.

Cross sections
N orm a lize d units
50
40
30
20
10
0
-45 -30 -15 0 15 30 45
Angle (deg)
From the images to the profiles and numerical data
Specular image Diffused image
Specular angular distributions
(Luminance and color)
Averaging
along the
hair tress
L
R
G
B
N orm alized units
6
5
4
3
2
1
0
Diffused angular distributions
(Luminance and color)
-45 -30 -15 0 15 30 45
Angle (deg)
Characterization of the
profiles with numerical
parameters such as maxima,
integrals and width
L
R
G
B
LUSTER

Luster qualifies the visual appearance of the object.
Luster is strongly linked to the idea of quality and beauty of an object.
Scientists have tried to compute a parameter that would quantify the visual luster
sensation.
Luster sensation is considered to depend on 3 main parameters:
The amount of
reflected light
Higher
luster
The more reflected light
there is, the higher the
luster is
The sharpness of the
reflection
Higher
luster
The sharper the reflection is,
the higher the luster is
Luster parameter
The background on which
the reflection is observed
Higher
luster
The darker the
background is, the higher
the luster is

Usual Luster formulae
Several Luster formulae have been developed and published by scientists using
goniometers and other instruments to tentatively quantify human perception of
Luster.
The parameters used in the formulae are :
• S the total amount of the specular light
• D the total amount of the diffused light
•θ1/2
the width of the specular light distribution
The 4 most used formulae are:
LRe ich − Robbins
=
S
D*θθθθ
1/
2
L
TRI
=
S
S + D
θθθθ ref
θθθθ 1/
2
Examples of luster formulae
L Stamm
S − D
S
These formulae were designed with a mathematical separation of specular
and diffused light (curve fitting and other method).
They can be used with the physical separation of diffused and specular light
distribution with polarization.
=
L Guiolet =
S
D

Usual Luster formulae
Bossa Nova Technologies luster:
L
New formula adapted to polarization imaging
Using the existing formulae with polarization imaging does not always gives a good
correlation with visual assessment (especially for dark hair).
We developed a formula that is adapted to polarization imaging.
It gives more dynamic range and better-correlated measurements.
It works on every type of hair and especially on dark samples where other formula
tended to lack sensitivity.
BNT
=
Sin
( D + S ) * W
out
visual
Presented at the TRI conference in 2008.
Article to come in the Journal of Cosmetic Science
Small
visual
width
large
angular
width

Experimental results: black hair
Black hair
Reflectance
(Arbitrary Units)
30
25
20
15
10
5
0
Reich-Robbins
+ 15.5 %
TRI
+ 26.8 %
Black Hair
-45 -30 -15 0 15 30 45
Angle (deg)
Specular Light Untreated
Diffused Light Untreated
Specular Light Treated
Diffused Light Treated
Bossa Nova Technologies
+ 116.1 %

Red hair
Reflectance
(Arbitrary Units) Experimental results: red hair
40
35
30
25
20
15
10
5
0
Reich-Robbins
+ 62.7 %
TRI
Red Hair
-45 -30 -15 0 15 30 45
Angle (deg)
+ 33.5 %
Specular Light Untreated
Diffused Light Untreated
Specular Light Treated
Diffused Light Treated
Bossa Nova Technologies
+ 84.5 %

Experimental results: blond hair
Reflectance
(Arbitrary Units)
50
45
40
35
30
25
20
15
10
5
0
Reich-Robbins
+ 80.1 %
Blond Hair
-45 -30 -15 0 15 30 45
Angle (deg)
TRI
+ 43.7 %
Specular Light Untreated
Diffused Light Untreated
Specular Light Treated
Diffused Light Treated
Bossa Nova Technologies
+ 109.5 %

intensity
Color analysis allows further understanding
Usual Luster formulae
Mathematical algorithm based on
color information
(Assuming that shine is white)
Images calculated from profiles
Color analysis allows a full decomposition
of light scattering in hair fibers
Intensity
Shine
Chroma
Diffused
Intensity= Shine + Chroma + Diffused
New research focused on internal reflection ?
New lusters taking into account chroma?

Color analysis allows further understanding
The internal reflection (chroma) plays a big part in the visual appearance of hair
Black Brown Red Blond
Dark Bright
• On untreated healthy hair, the shine (surface reflection) is comparable for all samples
• As the hair becomes brighter, the chroma (internal reflection) increases as well as the diffused light
• Chroma and diffused (carrying color information) play an important part on the visual appearance

Set-up
Data
Measurement
process
Shine-
Chroma-
Diffuse
components
separation
GONIOPHOTOMETER
Black box
Angular Profiles only
• Slow
• On single fiber (or a few)
• 1 angle at a time
Use of mathematical fits and
strong assumptions to
separate shine-chromadiffuse
components
Comparison with goniophotometer
SAMBA
SAMBA
SAMBA HAIR SYSTEM
Visual (verifiable with the eye)
Angular Profiles + Images
• On real tresses
• All angles in one shot
• No Mathematical fit
• Physical extraction of diffuse
component using polarization
• Physical separation of shinechroma
using color analysis

• SAMBA HAIR SYSTEM is a cutting-edge instrument that objectively quantifies visual
appearance of hair
• It uses a visual configuration (measurement verifiable with the human eye)
• Easy to operate (one button operation, seconds for a measurements)
• Well-known luster formulae are calculated in seconds on a complete hair tress
• The system offers numerical data as well as images
• A new BNT luster formula was developed to adapt to measurements made with polarization
imaging
• A powerful color analysis allows to fully understand light scattering on all types of hair.
• SAMBA HAIR SYSTEM provides a new physical analysis of the internal reflection (chroma).
New research should be conducted to evaluate the importance of chroma, leading to new lusters
taking into account chroma in the formula.
• A great tool widely used in the cosmetic industry to evaluate product efficacy, improve
formulations and substantiate claims.
Conclusion

Thank you
Come see us on boothH-06(タレスレーザー株式会社)
(Live demo of SAMBA Hair and Face systems)
東京都大田区大森北2-16-4 大阪府吹田市広芝町9-12
Bossa Nova Technologies
606 Venice Blvd, Suite B
Venice, CA 90291
タレスレーザー タレスレーザー株式会社 株式会社
USA
東京都大田区大森北 大阪府吹田市広芝町 東京都大田区大森北
Tel. 03-5753-4541(東京
Tel.
Tel. 310 577
東京 東京)
06-6192-7111(大阪
info@thaleslaser.co.jp
www.thaleslaser.co.jp
8114 大阪 大阪) 大阪
Email:
info@bossanovatech.com
www.bossanovatech.com