Abstract: An analogical mark printed on a document that includes a distribution of dots defined by a digital file, having, as a result of unanticipated unknowns in printing, an unpredictable variation, dot by dot, of at least one geometric characteristic of the printed dots where dots of the distribution of dots have, in the digital file, at least one geometric characteristic that digitally varies among dots, the geometric amplitude of the digital variation having the order of magnitude of said unpredictable variation and being less than an average dimension of the dots of the distribution of dots.

Abstract: A document securization method includes: a first step of forming a first mark (205, 210) on a first surface of a document by utilizing a first marking element, a second step of forming a second mark (215) on another surface of the document or in the depth of the document by utilizing a second marking element, the two marks are superimposed when the document is illuminated by back-lighting and at least one (215) of the marks is a mark whose copy, made using marking elements identical to those utilized for forming the mark, causes an error rate, measured dot by dot, that is greater than a predefined value.

Abstract: The method for authenticating a code with geometric areas whose shapes and/or colors vary according to a message includes: a step (115) in which the code with variable geometric areas is generated, according to a message, to provide geometric areas; a step (120 to 130) in which a digital authentication code is generated to provide numeric values and a step (135) in which an image of the geometric code areas is formed, including a part of the digital authentication code in at least some of its geometric areas and/or in at least one space between geometric areas.

Abstract: A process for securing a document including a step of printing a distribution of dots on said document, said printing, as a result of unanticipated unknowns in printing, causing an unpredictable variation, dot by dot, of at least one geometric characteristic of the printed dots and prior to said print step, a step generating said distribution of dots so that at least half the dots of said distribution are not laterally juxtaposed to four other dots of said dot distribution, and at least one dimension of at least one part of the dots of said distribution of dots is of the same order of magnitude as the average for the absolute value of said unpredictable variation. In embodiments, during the step generating the dot distribution, more than half the dots do not touch any other dot of said distribution.

Abstract: The document securization method includes: a step of printing a distribution of dots on the document, the printing, as a result of unanticipated unknowns in printing, causing an unpredictable variation, dot by dot, of at least one geometric characteristic of the printed dots and prior to the print step, a step of generating the distribution of dots so that dots of the distribution have at least one geometric characteristic that varies among dots, the geometric amplitude of the generated variation having the order of magnitude of the unpredictable variation. Preferably during the generation step, in the dot distribution: at least half the dots of the distribution are not laterally juxtaposed to four other dots of the dot distribution, and at least one dimension of at least one part of the dots of the dot distribution is of the same order of magnitude as the average for the absolute value of the unpredictable variation.

Abstract: A process for securing a document including a step of printing a distribution of dots on said document, said printing, as a result of unanticipated unknowns in printing, causing an unpredictable variation, dot by dot, of at least one geometric characteristic of the printed dots and prior to said print step, a step generating said distribution of dots so that at least half the dots of said distribution are not laterally juxtaposed to four other dots of said dot distribution, and at least one dimension of at least one part of the dots of said distribution of dots is of the same order of magnitude as the average for the absolute value of said unpredictable variation. In embodiments, during the step generating the dot distribution, more than half the dots do not touch any other dot of said distribution.

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 method for identifying a printing plate for a document includes: printing at least one document with the plate, capturing, at high resolution, at least one image of at least one part of the document, extracting a geometric characteristic of at least one captured image, storing the geometric characteristic extracted, for a candidate document where one seeks to determine whether the printing plate was used to print it, capturing, at high resolution, an image of the part of the candidate document corresponding to the part of the document for which a geometric characteristic has been stored, extracting the geometric characteristic of the image of the candidate document corresponding to the stored geometric characteristic; and determining whether a correlation measurement of the geometric characteristic for the candidate document and the stored geometric characteristic is greater than a pre-defined limit value.

Abstract: The method for authenticating a code with geometric areas whose shapes and/or colors vary according to a message includes: a step (115) in which the code with variable geometric areas is generated, according to a message, to provide geometric areas; a step (120 to 130) in which a digital authentication code is generated to provide numeric values and a step (135) in which an image of the geometric code areas is formed, including a part of the digital authentication code in at least some of its geometric areas and/or in at least one space between geometric areas.

Abstract: The document identification method comprises: a step of marking the document with an anti-copy mark that is identical for a plurality of documents, a step of reading an anti-copy mark, a step of generating an identification mark that can vary from one document to another and according to the reading of the anti-copy mark and a step of marking said document to form said identification mark on said document. In embodiments the method comprises, in addition, a step of printing a uniform area and the step of marking the document to form the identification mark comprises a step of emitting light with a laser in the uniform area. In embodiments the method comprises, in addition, a step of invisibly marking the identification mark on said document.

Abstract: The document identification method includes: a step of generating an image, a step of marking a plurality of documents to form the image on each document with unique variations on each document, the majority of the images formed on the documents presenting a physical anti-copy characteristic satisfying a predefined criterion such that the characteristic of the majority of the copies that can be produced based on these images do not satisfy the pre-defined criterion, a step of characterizing the variations to form a unique imprint of the mark formed, for each document and a step of memorizing the unique imprint.

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: The authentication process comprises: a step of transferring a holographic matrix onto a base, a step of marking the holographic matrix by laser shot, in order to produce a digital code that cannot be interpreted by the human eye preserving the optical diffraction properties of the holographic matrix, and designed to enable the detection of a copy of a document realized using the holographic matrix. Preferentially, during the marking step, the impact of each laser shot presents a greater dimension and a depth allowing the hologram's optical diffraction properties to be preserved.