The invention provides a powerful design strategy towards next-generation, multiplexed, lifetime-encoded tags via engineering intermetallic energy transfer in heterometallic metal-organic frameworks based on nonanuclear metal clusters. Precise manipulation of the luminescence decay dynamics over a wide microsecond regime can be achieved owing to the control over metal ordering in these systems. As an example of the invention, a novel, dynamic double encoding method that uses the braille alphabet was achieved by incorporating the materials into photocurable inks patterned on glass and interrogated via digital high-speed imaging. The facile synthesis and interrogation of these heterometallic metal-organic frameworks having complex and tunable optical properties enables next-generation, multiplexed optical tags.

In a general aspect, unique unclonable physical identifiers are applied and used. A method of applying the unique marker can include receiving an object having a surface feature and forming a unique marker on the surface feature of the object. The unique marker includes a distribution of elements and conforms with a morphology of the surface feature. The method further includes extracting orientation information from the unique marker. The orientation information can indicate relative spatial orientations of the respective elements. The method additionally includes generating a unique code for the object based on the orientation information. The surface feature can be facets, surface patterns, textures, or other indentations of the object. The surface feature can include a region of the object that is susceptible to tampering.

For identifying an original object comprising a surface essentially made of a first substance in a forgery-proof way, atoms of a second substance not soluble in the first substance are deposited on the surface. The surface is subjected to a beam of energized atoms providing movability to the atoms of the second substance in the surface to allow for a nucleation of a phase separation of a phase, in which the atoms of the second substance are concentrated. Then, an image of a surface pattern originating from the nucleation of the phase separation is taken and stored as a identifier for the original object. When a comparison image of a surface pattern of some object supposed to be the original object is compared to the identifier, the object is confirmed as being the original object, if the surface patterns in the identifier and the comparison image are identical.

In some embodiments, an apparatus includes a tag that may include an encapsulant and a plurality of three-dimensional objects randomly oriented within the encapsulant. Each three-dimensional object may include a plurality of characteristics defining at least one statistically unique signature. At least one of the characteristics may be dependent on the orientation of the object. In some instances, the plurality of three-dimensional objects may also be randomly distributed within the encapsulant, and at least one of the characteristics defining at least one statistically unique signature may be dependent on the distribution of the objects.

An optical multilayer body (100) according to the present invention has a first main surface and a second main surface that is on the reverse side of the first main surface. This optical multilayer body (100) comprises: an optical filter layer (110) which transmits infrared light, while diffusely reflecting visible light; and a recording medium layer (120) which is arranged on the second main surface side of the optical filter layer, while having a pattern that can be read with infrared light through the optical filter layer. This optical multilayer body is configured such that the pattern is not visible through the optical filter layer.

An optically variable device uses a data storage layer with a nano-optical bit system to store data. The optically variable device encodes the data using spectral signatures (such as colors) as variables. In some embodiments, the optically variable device uses angle multiplexing to store machine-readable data and an image. The optically variable device can be used as a secure data storage medium for a large volume of data. The storage capacity can be increased by increasing the number of color variables and by introducing additional variables such as intensity and polarization.

A color image display device comprising arrays of structural color pixels, where said structural color pixels may be formed on a single substrate layer or multiple substrate layers and are patterned by selective material deposition to display a color image in accordance with input color images or patterns. The structural color pixels comprise a plurality of microstructures and/or nanostructures, including without limitation, diffraction gratings, sub-wavelength structures, to display colors in red, green, blue in RGB color space or cyan, magenta, yellow in CMY color space. Examples include methods of activating and/or deactivating structural pixels using selective material deposition onto at least one layer of the color display device to form a color image. Further examples include product labels, authentication devices and security documents carrying customized or personalized information and methods for their manufacture.

Printer activatable environmental exposure indicators utilizing chemical encapsulation are disclosed herein. An example activatable environmental exposure indicator includes a substrate, an environmental indicator material configured to respond to a predetermined environmental stimulus, a plurality of microcapsules on or embedded in the substrate, and a bar code layer containing a bar code symbol and a viewing area. The microcapsules contain the environmental indicator material and are configured to respond to at least one of an activation temperature and an activation pressure by allowing the environmental indicator material to be released from the microcapsules. The environmental indicator material, after being released from the microcapsules, is configured to respond to exposure to the predetermined environmental stimulus by causing a detectable response.

In a general aspect, unique unclonable physical identifiers are applied and used. A method of applying the unique marker can include receiving an object having a surface feature and forming a unique marker on the surface feature of the object. The unique marker includes a distribution of elements and conforms with a morphology of the surface feature. The method further includes extracting orientation information from the unique marker. The orientation information can indicate relative spatial orientations of the respective elements. The method additionally includes generating a unique code for the object based on the orientation information. The surface feature can be facets, surface patterns, textures, or other indentations of the object. The surface feature can include a region of the object that is susceptible to tampering.

A meta-label includes an object and a plurality of nanostructures formed on one surface of the object and including a material including a water-soluble polymer and dielectric nanoparticles, wherein the plurality of nanostructures are arranged to display characters or patterns, and the characters or patterns include information about the object.