METHOD OF MAKING IDENTIFICATION MARK FOR MARKING VALUABLE ARTICLES AND VALUABLE ARTICLE WITH SAID MARK Russian patent published in 2011 - IPC G09F3/00 A44C17/00 G03H1/00 

FIELD: information technology.

SUBSTANCE: marked surface of the mark is polished and a processing layer (PL) is deposited, through which an image of the mark (M) is created on the surface in form of a diffraction structure (DS) which is optically visible in reflected light at diffraction angle. The DS is of the reflective phase grating type and is formed through ion etching of the surface together with the PL. Before formation of M on the surface, the DS is formed in the PL in form of a regular microrelief of a sinusoidal profile through ablation of the material of this layer using a pulse of interfering beams of coherent laser radiation. As a result, a DS is formed in the PL with holographic accuracy. The DS is formed through partial removal of material of the PL within its thickness. The image M in form of DS on the marked surface is also formed with holographic accuracy, which is provided through interfering coherent laser beams. The DS formed in the PLS is exposed to an ion beam. The process cycle for forming the M is carried out using a template mask together with the DS which forms the final image of the mark on the surface of the article.

EFFECT: high contrast of the mark with maximum definition.

7 cl, 7 dwg