RUMBA
Orientation measurements for
Straightness & Alignment studies
CURRENTLY UNAVAILABLE
Features
90° ORIENTATION SCALE
Can differentiate hair orientation from -45° to +45° with a 0.1° precision
FAST MEASUREMENT
Images acquisition takes less than 1 second
HIGH RESOLUTION
4 M pixels camera that allows hair fibers differentiation
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.
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.
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
Consumer head | |
Processed Images (Color-coded) Histogram Numerical data | |
down to 80 microns (stand-off=12") | |
Windows 10 Excel 2016 | |
Sensor | (178mm x 254mm x 229mm) - 5 kgs |
Lab setup | (185cm x 65cm x 80cm) |
Resources
Scientific publications
