Abstract: A security device is disclosed, including: a substrate having opposing first and second surfaces; on the first surface of the substrate, a surface relief structure formed of one or more cured, at least semi-transparent material(s); and on the second surface of the substrate, a print layer. In at least a first region of the security device in at least part of which the substrate is transparent or translucent, the surface relief structure and the print layer are each defined in accordance with a common image and are in alignment with one another, the surface relief structure exhibiting a first set of feature(s) of the common image and the print layer exhibiting a second set of feature(s) of the common image. The common image is exhibited by the surface relief structure and the print layer in combination with one another and the surface relief structure provides tactility to the common image.

Abstract: 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.

Abstract: A security device is provided, comprising one or more surface relief structure(s), each formed of one or more cured material(s), the surface relief structure(s) being disposed on a substantially flat substrate and defining a plurality of raised elements spaced from one another, the raised elements corresponding to elements of an image, whereby the plurality of raised elements varies across the surface relief structure(s) so as to exhibit a multi-tonal version of the image. Methods of manufacturing such devices are also disclosed.

Abstract: Presented are mutable cryptographic digital multimedia assets, methods for creating, transferring, updating, and playing such cryptographic digital multimedia assets, and decentralized computing systems with blockchain control logic for tracking the accessing, playing, displaying, transfer, or other consumption of those assets, and consequently altering them by digitally updating, altering, limiting, degrading, watermarking, or eventually destroying those digital multimedia assets.

Abstract: A method of inspecting a substantially transparent light control layer for an optically variable security device and a corresponding inspection apparatus, the substantially transparent light control layer including a surface relief defined by an array of substantially transparent refractive microstructures. The method includes: directing a beam of substantially collimated light towards a first region that is expected to contain the surface relief of the light control layer so as to generate an inspection light pattern; providing reference data that is indicative of a light control layer that meets a predetermined quality threshold; comparing the inspection light pattern with the reference data; and determining whether the light control layer meets the predetermined quality threshold based on the comparison.

Abstract: A security device is provided, comprising: a colour shifting element that exhibits different wavelengths of light at different viewing angles, and; an at least partially transparent light control layer covering at least a part of the colour shifting element and comprising a surface relief adapted to modify the angle of light from the colour shifting element, wherein; a first region of the light control layer comprises a first optical characteristic, whereby light at a first viewing angle from the first region of the light control layer is perceived to have a resultant optical effect that is the resultant of the wavelength of light exhibited at that viewing angle due to the combination of the colour shifting element and the surface relief of the light control layer, and the first optical characteristic, and; a second region of the light control layer either: (i) is substantially colourless such that light at the first viewing angle from the second region is perceived to have a resultant optical effect exhibite

Abstract: There is described a printing press (100***; 100****) adapted to carry out printing on a sheet-like or web-like substrate (S), in particular for the production of security documents such as banknotes, comprising a printing unit (2*; 2**; 2***; 2****) designed to print a first side (I) and/or a second side (II) of the substrate (S). The printing press (100***; 100****) further comprises an in-line casting device (80; 80*; 80**; 80***) adapted to apply a layer of material acting as an optical medium on a portion of a first side (I, II) of the substrate (S) and to replicate and form a micro-optical structure (L) in the layer of material acting as optical medium.

Abstract: A security device includes a luminescent material arranged in a first region, wherein the material luminesces in response to irradiation one excitation wavelength wherein the first region exhibits a luminescent visible colour; an array of viewing elements; and a masking layer positioned between the decorative layer and the array of viewing elements, the masking layer partially overlaps with first region, including first pattern elements defined by the masking material, and second pattern elements defined by the absence of the masking material wherein the decorative layer is visible through the second pattern elements; the masking material is non-luminescing in response to one excitation wavelength, and when the security device illuminates by at least one wavelength, where the array of pattern elements overlaps with the first region, the second pattern elements exhibit the luminescent visible colour, and the first pattern elements exhibit a visual appearance that's different to the luminescent visible colour.

Abstract: A security document and a method of forming a security document are disclosed. The method comprises: (a) providing a security document substrate having a security article integrated within or attached thereto, the security article being exposed within an aperture region in the security document substrate, the security article comprising a first optical effect layer that is visible within the aperture region, and; (b) applying, in said aperture region within which the security article is exposed, an array of substantially transparent refractive structures on the exposed security article, wherein the array of refractive structures cooperates with the first optical effect layer to exhibit a first optically variable effect.

Abstract: A security device and method of making thereof. The security device includes a colour shifting element that exhibits different colours dependent on the angle of incidence of light impinging upon the colour shifting element, and; an at least partially transparent light control layer covering at least a part of the colour shifting element and including a surface relief adapted to modify the angle of light incident upon the light control layer, wherein; the light control layer includes at least first and second functional regions having different refractive indices such that light incident upon the first functional region impinges upon the colour shifting element at a first angle of incidence, and light incident upon the second functional region impinges upon the colour shifting element at a second, different, angle of incidence.

Abstract: An optical device is disclosed, comprising; a colour shifting layer that exhibits different colours dependent on the angle of incidence of incident light, and; an array of substantially transparent microstructures covering at least a part of the colour shifting layer and configured to modify the angle of light incident to, and reflected from, the colour shifting layer, said array of microstructures arranged in accordance with a plurality of pixels of a colour image to be exhibited by the optical device, each pixel exhibiting a uniform colour, wherein; the array of microstructures comprises at least first and second sub-arrays of microstructures corresponding to respective first and second colour channels, each sub-array covering an area within a pixel corresponding to the proportion of the respective colour channel within the pixel such that the pixel exhibits the uniform colour, and further wherein; the microstructures of the first sub-array are configured to modify the angle of light incident to, and reflec

Abstract: An optical device including: a colour shifting layer that exhibits different colours dependent on the angle of incidence of incident light; first and second arrays of at least partially transparent microstructures covering at least part of the layer, configured to modify angle of light to generate a first optically variable effect, wherein: the first array is arranged as a set of image elements that cooperate to exhibit a first image, and the second is arranged to exhibit a second image, wherein the elements of the first array are interlaced with those of the second, and, the microstructures have at least one face that reflects incident light, whereby the first array is configured so, when viewed along a first viewing direction the device exhibits the first image, and the second is configured so, when viewed along a second direction the device exhibits the second image. Also, methods of manufacturing the device.

Abstract: A downhole acoustic transmitter has a piezoelectric transducer, an enclosure in which the piezoelectric transducer is housed, a transducer preload means which applies a selected compressive force against the transducer such that a mechanical preload is applied to the transducer, and an acoustic tuning element which has a first end coupled to the transducer preload means or the transducer, and an open second end. The acoustic tuning element is not coupled to anything but the transducer preload means or transducer, so the transducer preload means effectively has a second open end and thus can maintain the same preload compressive force on the transducer even when the transmitter is subjected to tension and compressive forces during operation.

Abstract: A method of forming an array of microimage elements that vary in their material composition is provided.

Abstract: A security device and method of making thereof. The security device includes a colour shifting element that exhibits different colours dependent on the angle of incidence of light impinging upon the colour shifting element, and; an at least partially transparent light control layer covering at least a part of the colour shifting element and including a surface relief adapted to modify the angle of light incident upon the light control layer, wherein; the light control layer includes at least first and second functional regions having different refractive indices such that light incident upon the first functional region impinges upon the colour shifting element at a first angle of incidence, and light incident upon the second functional region impinges upon the colour shifting element at a second, different, angle of incidence.

Abstract: A method of manufacturing a security document, including: providing a polymer substrate having first and second surfaces; and: applying an array of focussing elements to the first surface of the polymer substrate across a first region; forming an image array by: providing a die form having a surface including an arrangement of raised areas and recessed areas defining the pattern; applying a first curable material to the surface of the die form so it substantially fills the recessed areas; bringing a pattern support layer in contact with the surface of the die form so it covers the recessed areas; separating the pattern support layer from the surface of the die form so the first curable material in the recessed areas is removed from the recessed areas and retained on the pattern support layer; and at least partly curing the first curable material in one or more curing steps.

Abstract: A security device is disclosed, comprising an array of focussing elements with regular periodicity in at least a first direction, each focusing element having an optical footprint of which different portions will be directed to the viewer in dependence on the viewing angle; and an array of image elements with regular periodicity in at least the first direction overlapping the array of focusing structures, the image elements representing portions of at least two respective images, and at least one image element from each respective image being located in the optical footprint of each focusing structure.

Abstract: A downhole acoustic transmitter has a piezoelectric transducer, an enclosure in which the piezoelectric transducer is housed, a transducer preload means which applies a selected compressive force against the transducer such that a mechanical preload is applied to the transducer, and an acoustic tuning element which has a first end coupled to the transducer preload means or the transducer, and an open second end. The acoustic tuning element is not coupled to anything but the transducer preload means or transducer, so the transducer preload means effectively has a second open end and thus can maintain the same preload compressive force on the transducer even when the transmitter is subjected to tension and compressive forces during operation.

Abstract: A method of forming a polymer substrate for a security sheet includes: providing first and second overlapping polymer layers each providing outwardly facing surfaces, and a colour shifting element positioned between the first and second polymer layers adapted to provide a first optical effect to a viewer, wherein the first polymer layer includes a region substantially transparent to visible light such that the colour shifting element is viewable through the first polymer layer, and; joining together the first and second polymer layers in order to generate a polymer substrate wherein, during the joining step, a surface relief is formed in the outwardly facing surface of the first layer, the surface relief being adapted to interact with light from the colour shifting element in order to modify the first optical effect to provide a second optical effect different from the first optical effect.

Abstract: A method of forming a security device includes a colour shifting element, wherein the colour shifting element provides a first optical effect, the method includes; providing a light control layer over at least a part of the colour shifting element, the light control layer including a functional region and at least one non-functional region, wherein the functional region includes a surface relief adapted to modify the angle of light from the colour shifting element so as to generate a second optical effect different from the first optical effect, and wherein the non-functional region does not substantially modify the angle of light from the colour shifting element, and; wherein the at least one non-functional region is not discernible to the naked eye.