Environmental monitors for monitoring a predetermined environmental exposure, for example, an historical heat exposure such as a cumulative ambient heat exposure and/or a peak ambient heat exposure may include an environmental indicator material and a security material. The environmental monitor may be configured to attach to a host product for monitoring the predetermined environmental exposure of the host product, and additionally serve as an anti-counterfeiting indicator.

A security feature for safeguarding a document of value, includes an organometallic luminescent substance which, on excitation with radiation in the UV-A range, has emission of radiation in the visible wavelength range, especially with green and/or red light, wherein the luminescent substance is based on a polynuclear, heteroleptic lanthanoid complex of the formula (I) [Mx(NN ligand)a(OO ligand)b] (I) where x, a and b are natural numbers, where x2, a2 and b6; M is a lanthanoid selected from the group consisting of Eu and Th; the OO ligand is a ligand that coordinates via oxygen atoms and the NN ligand is a nitrogen ligand having a phenanthroline base skeleton.

A security or identification system including the application of two or more marker portions that include one or more compounds or mixture of compounds that fluoresce under exposure to electromagnetic radiation. The marker portions emit light at different wavelengths to each other when exposed to said electromagnetic radiation.

A security or identification system including the application of two or more marker portions that include one or more compounds or mixture of compounds that fluoresce under exposure to electromagnetic radiation. The marker portions emit light at different wavelengths to each other when exposed to said electromagnetic radiation.

A security device is provided, including: a surface relief structure formed of one or more cured materials on a substantially flat substrate, the surface relief structure defining a primary set of relief elements at a first scale and a secondary set of relief elements at a second scale which is smaller than the first, the primary set of relief elements including a plurality of raised protrusions spaced by recesses and the secondary set of relief elements being disposed on the tops of at least one of the raised protrusions and/or in at least one of the recesses. A security device including a structure formed of cured material(s) and an embossed structure is also provided. Methods of manufacture are also disclosed.

A security device is provided, including: a surface relief structure formed of one or more cured materials on a substantially flat substrate, the surface relief structure defining a primary set of relief elements at a first scale and a secondary set of relief elements at a second scale which is smaller than the first, the primary set of relief elements including a plurality of raised protrusions spaced by recesses and the secondary set of relief elements being disposed on the tops of at least one of the raised protrusions and/or in at least one of the recesses. A security device including a structure formed of cured material(s) and an embossed structure is also provided. Methods of manufacture are also disclosed.

Provided is a sheet recognition unit including: a light source capable of irradiating a sheet to be recognized with light having a specific wavelength; a light sensor that includes a plurality of light receiving elements respectively including a plurality of color filters that transmit infrared light and have different visible light transmission characteristics, receives, at the plurality of light receiving elements, light arriving from the sheet to be recognized, based on the light from the light source, and outputs light detection signals; and processing circuitry that performs arithmetic on light amount data based on the light detection signals output from the light sensor, depending on a ratio of genuine reference data to calculate an amount of at least one color in visible light and an amount of infrared light and recognize the sheet to be recognized based on calculated results.

Provided is a sheet recognition unit including: a light source capable of irradiating a sheet to be recognized with light having a specific wavelength; a light sensor that includes a plurality of light receiving elements respectively including a plurality of color filters that transmit infrared light and have different visible light transmission characteristics, receives, at the plurality of light receiving elements, light arriving from the sheet to be recognized, based on the light from the light source, and outputs light detection signals; and processing circuitry that performs arithmetic on light amount data based on the light detection signals output from the light sensor, depending on a ratio of genuine reference data to calculate an amount of at least one color in visible light and an amount of infrared light and recognize the sheet to be recognized based on calculated results.