Patent classifications
G03H1/0244
HOLOGRAM STRUCTURE
A main object of the present disclosure is to provide a hologram structure having excellent forgery preventability and designability. The present disclosure achieves the object by providing a hologram structure comprising: a hologram layer including a reflection type hologram forming region carrying a recorded phase type Fourier transform hologram that transforms an incident light from a point light source into a desired optical image; and a vapor deposition layer formed so as to come into contact with a concavo-convex surface of the reflection type hologram forming region of the hologram layer, and a size of the reflection type hologram forming region in plan view is in a range of 5 mm square or more and 50 mm square or less.
DIFFRACTION GRATINGS FORMED BY METASURFACES HAVING DIFFERENTLY ORIENTED NANOBEAMS
Metasurfaces provide compact optical elements in head-mounted display systems to, e.g., incouple light into or outcouple light out of a waveguide. The metasurfaces may be formed by a plurality of repeating unit cells, each unit cell comprising two sets or more of nanobeams elongated in crossing directions: one or more first nanobeams elongated in a first direction and a plurality of second nanobeams elongated in a second direction. As seen in a top-down view, the first direction may be along a y-axis, and the second direction may be along an x-axis. The unit cells may have a periodicity in the range of 10 nm to 1 ?m, including 10 nm to 500 nm or 300 nm to 500 nm. Advantageously, the metasurfaces provide diffraction of light with high diffraction angles and high diffraction efficiencies over a broad range of incident angles and for incident light with circular polarization.
METHOD FOR HOLOGRAPHIC MASTERING AND REPLICATION
A method for producing holograms with a multiplicity of holographic prescriptions from a single master is provided. A multiplicity of holographic substrates each having a first hologram is stacked on a second holographic recording medium substrate. The first hologram is designed to diffract light from a first direction into a second direction. When expose to illumination from the first direction zero order and diffracted light from each first hologram interfere in the second holographic recording medium substrate forming a second hologram. The second hologram is then copied into a third holographic recording medium substrate to provide the final copy hologram.
Recording holographic data on reflective surfaces
Lighting information comprising at least the reflectance data of a plurality of regions of an object surface is generated and printed out as a series of relightable holograms. Each of the printed holograms comprises the reflectance data of a corresponding region of the object. A model of the object is generated such that the model also comprises a plurality of portions corresponding to the regions of the object surface. The series of holograms are each affixed to a portion of the model such that a particular hologram of the series which encodes the reflectance data of a particular region of the object is affixed to the corresponding portion of the model. In an embodiment, the model of the object is generated from a metal. The series of holograms is engraved directly onto the metallic model such that a particular hologram of the series which encodes the reflectance data of a particular region of the object is engraved onto the corresponding portion of the metallic model.
Multilayer Body and Method for Producing a Security Element
A multilayer body (1, 2, 3) and a method for producing a security element are described. The multilayer body has a metal layer (21). An optically active surface relief is molded at least in areas in a first surface of the metal layer (21) facing the upper side of the multilayer body or forming the upper side of the multilayer body and/or in a second surface of the metal layer (21) facing the underside of the multilayer body or forming the underside of the multilayer body. In at least one first area (31 to 39) of the multilayer body the surface relief is formed by a first relief structure (61). In at least one direction (617) determined by an allocated azimuth angle, the first relief structure (61) has a sequence of elevations (612) and depressions (614), the elevations (612) of which follow on from each other with a period P which is smaller than a wavelength of visible light, wherein the minima of the depressions (614) lie on a base surface and the first relief structure (61) has a relief depth t which is determined by the spacing of the maxima of the elevations (612) of the first relief structure (61) from the base surface in a direction perpendicular to the base surface. The profile shape and/or the relief depth t of the first relief structure (61) is chosen such that the colored appearance of the light (52, 53) incident on the first area (31 to 39) at least at a first angle of incidence and directly reflected by the metal layer (21) in the first area or directly transmitted through the metal layer is modified, in particular is modified by plasmon resonance of the metal layer with the incident light.
DISPLAY MEMBER
A display member including a light transmission layer having a principal surface including a plurality of pixels; and a metal layer covering the principal surface, one or more of the pixels include a first region, one or more of the pixels include a second region, the first region has a plurality of first grooves or ridges each of which extends in a longitudinal direction in a first angle range of about 10 to +10 with respect to a first direction, the second region has a plurality of second grooves or ridges each of which extends in a longitudinal direction in a second angle range of about 65 to +65 with respect to a second direction perpendicular to the first direction, the second grooves or ridges form a diffraction structure, and the metal layer does not cover at least part of the first region and covers the second region.
SECURITY ELEMENT WITH PATTERN AND DOUBLE-SIDED HOLOGRAPHIC EFFECT
A security element is described includes a transparent first layer having a holographic surface structure, a first metal layer arranged on the first layer in a first pattern having transparent and non-transparent regions and a holographic surface structure, a second layer having a second holographic surface structure, and a second metal layer arranged on the second layer in a second pattern having transparent and non-transparent regions and a holographic surface structure. The, transparent regions of the first metal layer and the second metal layer are arranged to at least partly overlap each other and the non-transparent regions of the metal layers develop holographic effects on both sides of the security element which effects may be different. A process is described for making the security element, wherein an embossable radiation-sensitive polymer material is used to form the second layer.
Decorative element and security document comprising a decorative element
A decorative element (2), in particular in the form of a transfer film, a laminating film or a security thread, as well as a security document with a decorative element and a method for producing same is described. The decorative element (2) has a microstructure (4) which generates an optical effect in incident light and/or with light passing through. In a first area (32), the microstructure (4) has a base surface (40) and several base elements (41) which have in each case an element surface raised or lowered compared with the base surface (40) and a flank arranged between the element surface and the base surface (40). The base surface (40) of the microstructure defines a base plane spanned by coordinate axes x and y. The element surfaces of the base elements (41) in each case run substantially parallel to the base plane. In at least one or more first zones of the first area (32), the element surfaces of the base elements (41) and the base surface (40) are spaced apart in a direction running perpendicular to the base plane (40) in the direction of a coordinate axis z by a first distance which is chosen such that a color is generated in the one or more first zones in particular by interference of the light reflected at the base surface and the element surfaces in incident light and/or in particular by interference of the light transmitted through the element surfaces and the base surfaces with light passing through.
BROADBAND META-OPTICAL DEVICE
The present invention provides an optical component comprising a dielectric layer and a nanorod array; the nanorod array is formed on a surface of the dielectric layer and extends along a lateral direction and a vertical direction. The nanorod array comprises a plurality of nanorods extending along the dielectric layer. The nanorods have a gap between one another, and an angle is defined by two adjacent nanorods. A bump is formed at each of two ends of the nanorod.
Method of manufacturing a structure on a substrate
A method includes dividing a single beam emitted from a coherent light source into at least two branch beams, and causing the branch beams to cross each other at a predetermined interference angle thereby generating interference pattern. The method also includes irradiating a target surface of a substrate with the interference pattern. The method also includes dividing the target surface of the substrate into a plurality of predetermined shapes, and repeating a first substep of irradiating each predetermined shape with every shot of the interference pattern, and a second substep of conveying the substrate in a stepwise manner such that the predetermined shapes overlap each other in the stepwise manner. The method also includes causing a line-to-line pitch of the interference fringes in one of the predetermined shapes to align with the line-to-line pitch of the interference fringes in a next predetermined shape upon repeating the first and second substeps.