Abstract: A method for marking a surface by controlled periodic nanostructures includes: a step (500) of coding an item of information in the form of an image including values representative of the coded information and a step (506 to 514) of marking, dot by dot, an area of the surface with a polarized laser beam to form oriented nanostructures on or in the surface, by modulating the laser beam's polarization for each marking dot according to the value of a dot of the image. In embodiments, during the marking step, a pulsed laser is utilized with a duration of less than 10×10?12 seconds and an element of polarizing the light coming from the laser source and reaching the surface, designed to polarize the light according to a polarization axis that can vary according to a signal received by the polarization element, is utilized.

Abstract: A material marking method includes: generating a code; randomly selecting at least one area of the material; and marking by laser shot on the surface of, or inside the material in each the area of the material to represent the code there in a way that cannot be detected by the naked eye. Preferentially, the randomly selecting step is performed for each item of material to be marked. Preferentially, during the code generating step, a two-dimensional bar code is generated, and during the marking step, the two-dimensional bar code is represented. Preferably, the method includes marking the material in order to represent a mark visible to the naked eye, at least one part of a marking area of a mark visible to the naked eye is selected randomly and/or the visible mark bears an item of information representative of the position of at least one area where the code that cannot be detected by the naked eye is represented.

Abstract: A material marking method includes: generating a code; randomly selecting at least one area of the material; and marking by laser shot on the surface of, or inside the material in each the area of the material to represent the code there in a way that cannot be detected by the naked eye. Preferentially, the randomly selecting step is performed for each item of material to be marked. Preferentially, during the code generating step, a two-dimensional bar code is generated, and during the marking step, the two-dimensional bar code is represented. Preferably, the method includes marking the material in order to represent a mark visible to the naked eye, at least one part of a marking area of a mark visible to the naked eye is selected randomly and/or the visible mark bears an item of information representative of the position of at least one area where the code that cannot be detected by the naked eye is represented.

Abstract: A method for marking a surface by controlled periodic nanostructures includes: a step (500) of coding an item of information in the form of an image including values representative of the coded information and a step (506 to 514) of marking, dot by dot, an area of the surface with a polarized laser beam to form oriented nanostructures on or in the surface, by modulating the laser beam's polarization for each marking dot according to the value of a dot of the image. In embodiments, during the marking step, a pulsed laser is utilized with a duration of less than 10×10?12 seconds and an element of polarizing the light coming from the laser source and reaching the surface, designed to polarize the light according to a polarization axis that can vary according to a signal received by the polarization element, is utilized.

Abstract: The device comprises a laser-type coherent light radiation source transmitting ultrashort pulses, a dynamic beam shaping arrangement and an arrangement for using and processing a laser beam. The dynamic beam shaping arrangement comprises an optical system including a part for actively modifying the laser beam wavefront and a detecting part, excepting a phase meter, used for three-dimensionally shaping the beam. These parts are connected by a feed-back circuit and the active modifying part comprises a first fixed or active component and a second active component.