Abstract: A method for characterizing particle objects comprises generating a radiation beam, illuminating with the radiation beam an observation region transited by a particle object, collecting an interference image determined by an interference between a transmitted fraction and a part of the scattered fraction of the radiation beam that propagates around the direction of the optical axis, collecting a part of the scattered fraction that propagates at the scattering angle, and measuring at least one scattered radiation intensity value determined by the part of the scattered fraction, calculating, from the interference image, a pair of independent quantities that define the complex field of the first part of the scattered fraction, calculating, starting from the pair of independent quantities, a theoretical value of scattered radiation intensity, and comparing the measured value with the theoretical scattered radiation intensity value.

Abstract: Yarn is disclosed including textile fibers and metallic fibers. The textile fibers are either natural or artificial fibers. The cut length of the textile fibers is between 50 and 100 millimeters. The metallic fibers are fabricated from Group VIII metals or their alloys. In addition, the metallic fibers have a cut length measuring between 20 and 80 millimeters.