Decorative sheets comprising metallized or iridescent plastic flakes

摘要

The present invention relates to a method and device for measuring at least one transverse dimension of a textile thread by means of an optical system. & br / the measurement device comprises a source of coherent light (s), which emits a beam ′ (10) on a cylindrical lens (11). Two blades (12,13) to move axially defined on either side of the thread (14), two identical slots (15, 16) to form two secondary sources arranged to interfere with the aid of an optical system (17). It is possible to deduce the transverse dimension of the wire of the difference between the fringes (18) of the resulting interference pattern.