RUMBA

Orientation measurements for
Straightness & Alignment studies

RUMBA Hair care alignment orientation styling testing claims research polarization vitro vivo

Features

RUMBA polarization modulation angle orientation alignment hair frizz curl curly static messy principle infrared lab setup in-vivo in-vitro logo High resolution fast 2

90° ORIENTATION SCALE

Can differentiate hair orientation from -45° to +45° with a 0.1° precision

RUMBA polarization modulation angle orientation alignment hair frizz curl curly static messy principle infrared lab setup in-vivo in-vitro logo High resolution fast

FAST MEASUREMENT

Images acquisition takes less than 1 second

RUMBA polarization modulation angle orientation alignment hair frizz curl curly static messy principle infrared lab setup in-vivo in-vitro logo High resolution

HIGH RESOLUTION

4 M pixels camera that allows hair fibers differentiation

RUMBA polarization modulation angle orientation alignment hair frizz curl curly static messy principle infrared lab setup in-vivo in-vitro logo

LAB SETUP

Enclosure to block external light and
air flow

Overview

RUMBA has been specifically designed to measure the orientation of hair fibers, and compute straightness and alignment coefficient for product efficiency analysis. It is used in the cosmetic industry for claims and development of product such as straightening irons, conditioners, hair sprays, etc.  It works for any type of hair, from straight to curly, from black to blond and white. 

RUMBA comes as a turn-key system including the imaging sensor and its controller box, a computer with a dedicated software as well as a lab setup.  The measurement can be made on hair tresses or directly on a consumer’s head, thanks to an acquisition time of less than 1 second

RUMBA polarization modulation angle orientation alignment hair frizz curl curly static messy principle infrared lab setup in-vivo in-vitro

A user-friendly software allows the user to easily set the parameters of the acquisition, and do the measurement in one click. A complete analysis of the distribution of the hair fiber orientation (mean angle, standard deviation, etc.) of the hair is delivered in seconds. Numerical data (straightness, alignment, spatial analysis, etc.), and images can be quickly compared and exported for reports, presentations or post processing.

Principle

RUMBA is a polarization imaging system that takes successive images of a hair sample illuminated with infrared LED  and under several polarization states using a rotating polarizer (image below). Those images gives a modulated intensity on each pixel. This modulation is caused by the birefringence of the hair fiber and contains the angle signature that we can extract to build an orientation image of the sample.

RUMBA polarization modulation angle orientation alignment hair frizz curl curly static messy principle infrared
RUMBA polarization modulation angle orientation alignment hair frizz curl curly static messy

We can therefore map the orientation on a 2D image to visualize the whole sample. An example of the color-coded image of the orientation of a hair sample is displayed on the adjacent figure (left image) : each orientation is identified by a specific color.

From this orientation data, we can define a coefficient that relates to straightness : the straighter the hair fibers in your swatch are, the closer to a single angle value the distribution of your orientation will be. The standard deviation of such a distribution is therefore inversely proportional to the perception of straightness.

The same process is done for the alignment, as we define the alignment of a  hair swatch as the fact that hair fibers are “locally straight”. We essentially compute a straightness coefficient on a small scale of the 2D mapping of the orientation, which allow us to get a straightness coefficient on every pixel of the image.

Orientation/Alignment images

From those coefficients calculated in every point of the image, we can reconstruct an alignment image (above figure – right image). Such an image visually enhances the contrast between low-alignment area – like frizz – and high-alignment area.

Specifications

HAIR SAMPLE SPECIFICATIONS
Hair type
Any Color - Any Shape
Hair sample
Hair swatch - Mannequin head -
Consumer head
DATA
Data format
Raw Images (Monochrome)
Processed Images (Color-coded)
Histogram
Numerical data
Measurement uncertainty
1% over 24h
Data repeatability
< 1%
GENERAL SPECIFICATIONS
Image resolution
4M pixels
Illumination
Pulsed LEDs @850nm (eye-safe)
Spatial resolution
130 microns (stand-off=23")
down to 80 microns (stand-off=12")
Area of measurement
12" x 8" at 23" stand-off
Acquisition time
< 1 second - allows in-vivo measurements
Computer
Laptop or All-in-One
Windows 10
Excel 2016
Weight-dimensions
Sensor
7" x 10" x 9 " - 10 lbs
(178mm x 254mm x 229mm) - 5 kgs
Dimensions
Lab setup
72"L x 24"W x 31 "H
(185cm x 65cm x 80cm)
Power requirements
110/220 V - 50/60 Hz

Resources

Scientific publications​