Abstract: Systems and methods described for embossing micro-scale features are provided. On various substrates. Micro-scaled features can contain nanometer to micrometer structural features. Various embodiments may relate to methods and systems that may allow substrates, non-limiting examples of which may include metals such as silver, copper, tin, gold, or the like, to be embossed to diffract light into various colors that can be refracted at various perspective angles. High-quality grooves can be machined down to the sub-micron or nanometer regime to generate embossment moulds for fast, single-step, repeated (e.g. in the order of tens to thousands) replication of gratings on bulk metallic substrates using a same embossing die without significant loss of embossing quality.

Abstract: A colorimetric sensor including: a substrate; and a periodic array of nanostructures provided to the substrate, wherein the periodic array of nanostructures is configured to provide a change in color based on a medium being within a predetermined distance of the colorimetric sensor. The periodic array of nanostructures may be configured (width, height, spacing) to provide optical wave-guide properties or surface Plasmon resonance in order to effect a distinct change in color based on the medium being sensed. In some cases, the colorimetric may include a reflective surface to reflect light from the sensor. Further, the reflective surface may be metallic.