| abstract |
Isolated elements, such as fibers (12), are poured one by one into the flow of a fluid, a nozzle orients these elements so that they are substantially parallel, according to their largest dimension (this is i.e. their length), to the direction of flow of the fluid. The element then enters a sampling area (36) where a sensor records data such as its running speed in this area. In an ideal configuration, a collimated ray of light (34) and two juxtaposed photodetectors (46a, 46b) positioned so as to measure the extinction of the light source caused by the passage of the fibers in the sampling area. There may be another sensor (52) which detects the light scattered forward at an angle of about forty degrees. The signals communicated by the sensors make it possible to prepare data corresponding to parameters such as the length, the width of the fiber ribbon, the fineness, the surface of the cross section, the maturity, the circularity of the cross section, the shape , surface roughness, etc. Optical filtering provides information on the composition (natural or artificial) and appearance (color and polarization). |