Abstract: Particle (1) which comprises a core (2) made of copper, of a copper alloy, of aluminium or of an aluminium alloy, covered with an external layer (3), where the external layer (3) is formed from metal nanoparticles or carbon nanotubes.

Abstract: Particle (1) which comprises a core (2) made of copper, of a copper alloy, of aluminium or of an aluminium alloy, covered with an external layer (3), where the external layer (3) is formed from metal nanoparticles or carbon nanotubes.

Abstract: The invention concerns a biometric capture optical device (1) comprising a prismatic optical element (2) having one side (4) appearing in a window (3) to provide a support surface for a bodily limb and illuminating means (6) designed to illuminate the side (4) from within the element (2) and form by total reflection a biometric image of the bodily limb; in addition, luminous information display means are located beneath the element (2) opposite the window (3) so as, in the absence of the bodily limb on the side (4), to transmit, without total reflection, through the window (3) a luminous information image visible from outside (15).

Abstract: The invention relates to a method of checking the authenticity of biometric sensing performed optically, in which a body organ (6) placed on a main face (2) of a prismatic optical element (1) is illuminated (8) with total internal reflection, and then the reflected radiation carrying the biometric image of said body organ is picked up (9). The method comprises the steps of superposing on the main illumination (8) on the main face (2) of the prismatic optical element (1), encoding illumination (14) in such a manner that it is the encoded combined radiation that is reflected by said main face (2) and picked up (9), and comparing (17) the encoded combined radiation with the encoding of the encoding illuminating radiation; thereby detecting the authenticity of the reflected radiation conveying the biometric image associated with the body organ placed on the main face.

Abstract: The invention concerns a biometric capture optical device (1) comprising a prismatic optical element (2) having one side (4) appearing in a window (3) to provide a support surface for a bodily limb and illuminating means (6) designed to illuminate the side (4) from within the element (2) and form by total reflection a biometric image of the bodily limb; in addition, luminous information display means are located beneath the element (2) opposite the window (3) so as, in the absence of the bodily limb on the side (4), to transmit, without total reflection, through the window (3) a luminous information image visible from outside (15).

Abstract: The invention relates to a method of checking the authenticity of biometric sensing performed optically, in which a body organ (6) placed on a main face (2) of a prismatic optical element (1) is illuminated (8) with total internal reflection, and then the reflected radiation carrying the biometric image of said body organ is picked up (9). The method comprises the steps of superposing on the main illumination (8) on the main face (2) of the prismatic optical element (1), encoding illumination (14) in such a manner that it is the encoded combined radiation that is reflected by said main face (2) and picked up (9), and comparing (17) the encoded combined radiation with the encoding of the encoding illuminating radiation; thereby detecting the authenticity of the reflected radiation conveying the biometric image associated with the body organ placed on the main face.