A method of printing authentication indicia by applying an at least amplitude-modulated halftone print in a detection zone to an object uses adjoining halftone cells, in each of which a halftone dot is printed from a matrix of printable halftone elements, individual tone values of the halftone print corresponding in each case to a halftone plane of a halftone mountain for a halftone dot. In this process, the assigned screen plane of the screen mountain is modified in the detection zone in a predetermined manner for a plurality of tone values of screen dots to be printed, so that a predetermined matrix image of the screen elements to be printed is assigned to it while the tone value of the print remains constant.

A system and method for creating latent image indicia that includes a variable mark. The latent image indicia is made of pigmented ink that can only be viewed when illuminated with a specific frequency of light. The pigmented ink is printed in a solid patch by a conventional printing process. The variable mark in the pigmented ink is created by laser ablation of the pigment. The laser ablation is done after the ink printing as a separate step.

Disclosed is a plastic product with authenticity to be determined, the plastic product including: a base made of a plastic material, and a luminescent material included in the base and configured to emit light including a second wavelength with respect to incident light including a first wavelength, in which the determination of the authenticity is performed by irradiating the plastic product with the incident light and then detecting the emitted light. According to the present invention, it is possible to easily determine the authenticity of the plastic product by a simple method of detecting a spectrum of the light emitted from the plastic product.

Disclosed is a plastic product with authenticity to be determined, the plastic product including: a base made of a plastic material, and a luminescent material included in the base and configured to emit light including a second wavelength with respect to incident light including a first wavelength, in which the determination of the authenticity is performed by irradiating the plastic product with the incident light and then detecting the emitted light. According to the present invention, it is possible to easily determine the authenticity of the plastic product by a simple method of detecting a spectrum of the light emitted from the plastic product.

Security article and method for producing a security article. The method includes microprinting on a patch an array of microimages, placing a first translucent layer over the substrate and first patch, and laminating the substrate, the patch, and the first translucent layer using a lamination tool. The resulting security product includes a microlens array is located in the first translucent layer in register with the patch such that microimages have a one-to-one correspondence with lenses of the array of microlenses, wherein when the microimage array is viewed by a viewer through the microlens array, a composite image is visible to a viewer of the security article.

Security article and method for producing a security article. The method includes microprinting on a patch an array of microimages, placing a first translucent layer over the substrate and first patch, and laminating the substrate, the patch, and the first translucent layer using a lamination tool. The resulting security product includes a microlens array is located in the first translucent layer in register with the patch such that microimages have a one-to-one correspondence with lenses of the array of microlenses, wherein when the microimage array is viewed by a viewer through the microlens array, a composite image is visible to a viewer of the security article.

An identification apparatus or system includes an estimation unit that estimates an operating distance between the surface of an optical device and an imaging unit as an estimated value. A reference distance refers to the distance between a first face of an identification target and the imaging unit and at which light diffracted by a diffraction grating is capable of being recorded by the imaging unit. A first determination unit is included that determines whether the estimated value matches the reference distance and a second determination unit that determines whether an image captured by the imaging unit matches a reference image. Conditions for identifying the optical device as the identification target include a condition that the first determination unit determines that the estimated value matches the reference distance and a condition that the second determination unit determines that the image captured by the imaging unit matches the reference image.

A security device includes an array of lenses and a plurality of first and second segments disposed under the array of lenses. At a first viewing angle, the array of lenses presents a first image for viewing without presenting the second image for viewing, and at a second viewing angle different from the first viewing angle, the array of lenses presents for viewing the second image without presenting the first image for viewing. At least one first or second segment can include one or more microstructures or one or more nanostructures configured to produce one or more colors for the first or second image.

A security device includes an array of lenses and a plurality of first and second segments disposed under the array of lenses. At a first viewing angle, the array of lenses presents a first image for viewing without presenting the second image for viewing, and at a second viewing angle different from the first viewing angle, the array of lenses presents for viewing the second image without presenting the first image for viewing. At least one first or second segment can include one or more microstructures or one or more nanostructures configured to produce one or more colors for the first or second image.

An optical device includes an array of lenses and a plurality of segments disposed under the array of lenses. The plurality of segments corresponds to a plurality of images. Upon tilting the device at different viewing angle, the array of lenses presents images sequentially. In some examples, individual ones of the segments can comprise specular reflecting, transparent, diffusely reflecting, and/or diffusely transmissive features. In some examples, individual ones of the segments can comprise transparent and non-transparent regions. Some examples can incorporate more than one region producing an optical effect.