A method and a device for banknote classification and recognition based on a Lab color space are provided for improving the denomination recognition rate. The method includes obtaining an RGB image of a banknote to be detected; calculating gray values Gray R, Gray G and Gray B of the RGB image in red (R), green (G) and blue (B) wavebands; converting the gray values Gray R, Gray G and Gray B into gray values Gray a and Gray b in the Lab color space; and substituting a product of Gray a and Gray b and a difference between the absolute value of Gray a and the absolute value of Gray b into preset formulas to determine a category of the banknote to be detected.

An improved system and method for reading an upconversion response from nanoparticle inks is provided. A is adapted to direct a near-infrared excitation wavelength at a readable indicia, resulting in a near-infrared emission wavelength created by the upconverting nanoparticle inks. A short pass filter may filter the near-infrared excitation wavelength. A camera is in operable communication with the short pass filter and receives the near-infrared emission wavelength of the readable indicia. The system may further include an integrated circuit adapted to receive the near-infrared emission wavelength from the camera and generate a corresponding signal. A readable application may be in operable communication with the integrated circuit. The readable application receives the corresponding signal, manipulates the signal, decodes the signal into an output, and displays and/or stores the output.

An improved system and method for reading an upconversion response from nanoparticle inks is provided. A is adapted to direct a near-infrared excitation wavelength at a readable indicia, resulting in a near-infrared emission wavelength created by the upconverting nanoparticle inks. A short pass filter may filter the near-infrared excitation wavelength. A camera is in operable communication with the short pass filter and receives the near-infrared emission wavelength of the readable indicia. The system may further include an integrated circuit adapted to receive the near-infrared emission wavelength from the camera and generate a corresponding signal. A readable application may be in operable communication with the integrated circuit. The readable application receives the corresponding signal, manipulates the signal, decodes the signal into an output, and displays and/or stores the output.

A value document with a carrier element and a foil element arranged in a partial region of the carrier element. The carrier element has, at least in the partial region, a luminescence marker which is adapted to give off luminescence radiation which has at least a first wavelength and a second wavelength in each case in the infrared spectral region. The foil element has a reflection layer and a spectral selection layer. The selection layer is arranged between the carrier element and the reflection layer. The reflection layer is configured to reflect infrared radiation and the selection layer is configured to spectrally selectively inhibit transmission of infrared radiation. The inhibition of the transmission of the first wavelength and the inhibition of the transmission of the second wavelength differ by at least 10%.

A value document with a carrier element and a foil element arranged in a partial region of the carrier element. The carrier element has, at least in the partial region, a luminescence marker which is adapted to give off luminescence radiation which has at least a first wavelength and a second wavelength in each case in the infrared spectral region. The foil element has a reflection layer and a spectral selection layer. The selection layer is arranged between the carrier element and the reflection layer. The reflection layer is configured to reflect infrared radiation and the selection layer is configured to spectrally selectively inhibit transmission of infrared radiation. The inhibition of the transmission of the first wavelength and the inhibition of the transmission of the second wavelength differ by at least 10%.

According to a first aspect of the invention, there is provided a method of deriving information from an optically readable security element, comprising: optically reading the optically readable security element, the optically readable security element comprising at least one optically readable structure, optically readable in response to excitation of the optically readable structure; the reading comprising determining data indicative of an optical property of the optically readable security element using first emission electromagnetic radiation, emitted in response to excitation of the optically readable structure; the deriving information further comprising using the determined data indicative of an optical property, in combination with a temporal excitation-emission relationship related to the optically readable structure, to derive the information.

According to a first aspect of the invention, there is provided a method of deriving information from an optically readable security element, comprising: optically reading the optically readable security element, the optically readable security element comprising at least one optically readable structure, optically readable in response to excitation of the optically readable structure; the reading comprising determining data indicative of an optical property of the optically readable security element using first emission electromagnetic radiation, emitted in response to excitation of the optically readable structure; the deriving information further comprising using the determined data indicative of an optical property, in combination with a temporal excitation-emission relationship related to the optically readable structure, to derive the information.

The optical sensor of the present disclosure includes: a light source configured to emit irradiation light to a target; a light receiver configured to receive a first incident light, a second incident light, and a third incident light travelling from the target and having different wavelength bands; and a controller configured to control the light source. The light receiver includes: a first light-receiving element configured to receive the first incident light and the second incident light and not to receive the third incident light; and a second light-receiving element configured to receive the third incident light and to receive neither the first incident light nor the second incident light.

A user device may cause light to be emitted at a security article by one or more light emission devices of the user device. The user device may obtain from a first set of one or more optical sensor devices of the user device first sensor data associated with the security article, and may obtain from a second set of one or more optical sensor devices of the user device second sensor data associated with the security article. The user device may determine, based on the first sensor data and the second sensor data, one or more characteristics of a security feature of the security article. The user device may determine, based on the one or more characteristics of the security feature, whether the security article is authentic. The user device may cause, based on determining whether the security article is authentic, one or more actions to be performed.

A method of obtaining a plurality of infrared images of a banknote that involves simultaneously illuminating the banknote with infrared light at a first wavelength and infrared light at a second wavelength, capturing an image of the banknote with an RGB camera, obtaining from both a first output channel signal and a second output channel signal of the RGB camera sensor where the intensity distribution of the infrared light at the first wavelength and the intensity distribution of the infrared light at the second wavelength uses a first calibration coefficient and a second calibration coefficient of the RGB camera sensor, producing separate infrared images of the banknote at the first wavelength and the second wavelength from the respective intensity distributions.