Abstract: The invention relates to a device (4) in the form of a medical prosthesis (9, 17), medical osteosynthesis device, hearing aid or hearing aid housing, essentially made of metal, wherein the device (4, 9, 17) comprises at least one optical diffractive element with a grating (6) which is directly embossed in an exposed metal surface in the form of a security and/or identification element. The invention furthermore relates to methods for making such devices and to uses of such devices.

Abstract: The invention relates to a method for producing a metal stamp for embossing a nano- or microstructure on a metal device (4), comprising the following steps for producing a 3D structured embossing area (3) on the stamp: a) providing a master (30) having a structured surface (30a), and replicating said master (30a) in the surface of a soft stamp (31); b) forming an imprint (32) on the soft stamp (31a) using a cross-linkable material to form an imprint structured surface (32a), before, while or after contacting an opposite side of the imprint (32) with said surface portion of the metal stamp, and removing said soft-stamp (31) exposing said imprint structured surface (32a); c) etch-opening said surface (32a) using a first set of etching conditions; d) using a second set of etching conditions, different from the first ones, etching the surface of the metal stamp to form said embossing area (3).