Device and method to optically authenticate an object
Abstract
The device has a set of nanometric pads distributed at a surface of a support e.g. object, for forming a homogeneous planar array, where each pad is a non-linear optical diffraction and diffusion pad. Each pad extends remote from the support along an axis. The pads, which are non centro-symmetric, are distributed on the support along different orientations for creating a constructive interference between non-linear optical responses of the pads. Each pad includes multiple parts, where one of the parts includes gold or silver. An independent claim is also included for a method for optical authentication of an object.