COMPOSITE FIBER, TEXTILE PRODUCT COMPRISING SUCH A COMPOSITE FIBER, METHOD FOR INSCRIBING OPTICAL CODE ELEMENTS, ARRANGEMENT FOR CARRYING OUT SAID METHOD, AND READING DEVICE
In order to make textile products (32) counterfeit-proof, a composite fiber is disclosed which comprises a core (2) extending at least along part of the fiber length and a shell (3) surrounding the core (2). The shell is made of a plastic which can be locally modified, especially melted, with the help of light radiation or laser radiation. Furthermore, the shell is provided with optical code elements (4) at least along part of the length thereof, said optical code elements (4) being formed by locally modifying or melting the shell by means of the light radiation or laser radiation.