Disclosed herein is a method comprising: exposing a document to radiation; capturing a first image with a portion of the radiation that has transmitted through the document, with a first characteristic X-ray emitted from the document caused by the radiation, or with both, using a radiation detector; determining a pattern from the first image; determining authenticity of the document based on the pattern.

Using software to process images and/or digital representations of paper currency to determine if currency has a value greater than the face value of the currency to any person or persons. Software that can determine from images and/or digital representations (known or unknown) numismatic value, or value greater than the face value of the currency to any person or persons and indicia of numismatic value, or increased value, including, but not limited to: ink smearing, misaligned serial numbers, misaligned seals on currency, non-matching serial numbers, off center printing, off-center cutting, paper currency of small or limited print runs, fancy serial numbers, missing or off-center watermarks, errors in security features, holograms, ultra-violet features, magnetic features, microprinting, etc. to determine a numismatic value.

Using software to process images and/or digital representations of paper currency to determine if currency has a value greater than the face value of the currency to any person or persons. Software that can determine from images and/or digital representations (known or unknown) numismatic value, or value greater than the face value of the currency to any person or persons and indicia of numismatic value, or increased value, including, but not limited to: ink smearing, misaligned serial numbers, misaligned seals on currency, non-matching serial numbers, off center printing, off-center cutting, paper currency of small or limited print runs, fancy serial numbers, missing or off-center watermarks, errors in security features, holograms, ultra-violet features, magnetic features, microprinting, etc. to determine a numismatic value.

The present invention firstly relates to a security feature for a security or value document. The security feature comprises a zinc sulfide lurninophore in the form of particles. The zinc sulfide lurninophore has the general chemical formula ZnS: Cu.sub.x, M.sub.y, X.sub.z; here, M represents one or more elements from a group comprising the chemical elements Co, In and Ni; X represents one or more elements from a group comprising the halides F, Cl, Br and I; and the following applies: 0 < x < 0.002 and 0 ≤ y < 0.00015 and 0 ≤ z < 0.00050. The particles each have cubic phase portions and hexagonal phase portions. When excited by an electrical field, the zinc sulfide luminophore emits a first radiation in the range of the light spectrum between 580 nm and 780 nm. When excited by heating the luminophore to a temperature between 100° C. and 150° C., the zinc sulfide luminophore emits a second radiation in the light spectrum. Furthermore, the invention relates to a security and value document, which may for example be a bank note or a passport, an identity card, a driving license or a postage stamp. The invention also relates to a method for detecting and/or verifying the security feature according to the invention.

The present invention relates to a method for authenticating a document comprising at least one line of anti-counterfeit patterns spaced from each other, the positions of the anti-counterfeit patterns being random, and a partial anti-counterfeit pattern being provided at an edge line of said document, the method comprising the following steps of:

receiving a digital image of said document, said digital image comprising said partial anti-counterfeit pattern in a first edge area corresponding to said edge line;

selecting said first edge area;

copy-pasting said first edge area adjacent to a second edge area of the digital image to generate a combined digital image, said second edge area being opposite to said first edge area, wherein content, which is comprised in said second edge area and located on the same line as said partial anti-counterfeit pattern, and said partial anti-counterfeit pattern jointly form a combined pattern;

authenticating said document by taking into account said combined pattern.

A method is provided for checking a substrate with a specified luminescent substance incorporated and/or applied areally. A substrate luminescent characteristic value for the substrate is ascertained, for which purpose a number N of luminescence intensity values are captured at respectively different locations on the value document, and the substrate luminescence characteristic value is ascertained in dependence on a rank order of the luminescence intensity values. It can be checked whether the substrate luminescence characteristic value meets a specified criterion.

Described is a chiral liquid crystal polymer (CLCP) layer or pattern which comprises randomly distributed craters of controlled mean diameter and/or density. The density and/or mean diameter of the craters can be controlled, for example, by adjusting the wetting of a substrate by a CLCP precursor composition, the development time of the precursor composition, and the thickness of the applied precursor composition.

A system and associated method, the system including an item including a substrate including a polymer material and a first diffraction feature configured to diffract incident radiation into the substrate at an angle greater than the critical angle and launch the incident radiation into a waveguide transmission mode within the substrate to transmit the incident radiation laterally within the substrate, and a computing device including a radiation source configured to irradiate the item at a location of the first diffraction feature directly or indirectly on or within the substrate such that radiation is transmitted laterally within the substrate and a camera configured to measure emitted radiation from the substrate after lateral transmission of the incident radiation, where, in connection with irradiating with the radiation source and measuring the emitted radiation with the camera, the computing device is disposed in contact with the substrate.

A document forgery detection method comprising using at least one processor for providing at least one histogram of gray level values occurring in at least a portion of at least one channel of an image assumed to represent a document including text, the histogram having been generated by image processing at least a portion of at least one channel of an image assumed to represent a document including text, the image having been sent by a remote end user to an online service over a computer network, evaluating monotony of at least a portion of the at least one histogram; and determining whether the image is authentic or forged based on at least one output of the evaluating.

A method and system for authenticating an item includes providing the item including a polymer substrate comprising a polymer material and a doping material, the polymer material and the doping material configured to transmit radiation laterally through the polymer substrate, and the doping material capable of scattering radiation and absorbing radiation of at least one specific wavelength to generate a spectral signature in a spectral band of wavelengths of the transmitted radiation, irradiating the item with incident radiation characterized by a spectral band of wavelengths spanning a band of wavelengths including the at least one specific wavelength absorbed and scattered by the doping material, detecting the spectral signature after the radiation is transmitted laterally through the polymer substrate, and determining a code associated with the spectral signature.