A method and system for forming a holographic structure in a material. The holographic structure is configured to project a selected target image in the far field under illumination of the holographic structure by a laser. The method calculates a modified design for the holographic structure that encodes a unique identifier within the holographic structure for projecting the target image. The method modifies the material by mapping features corresponding to the modified design into the material so as to form the holographic structure. A basic check of the authenticity of the material is performed by checking whether a projected replica of the target image is as expected. A more detailed check of the authenticity of the material is performed by directly inspecting the features in the holographic structure.

An apparatus for producing an optically variable film includes a laser configured to emit a beam, a telescoping lens section having a first lens and a second lens spaced apart by a first distance and an interferometer configured to direct the beam toward a workpiece. The laser may be operated at a predetermined power level and the first and second lenses are sized and spaced relative to one another to direct the beam onto the workpiece at about 200-230 dots per inch. The workpiece may include a polyethylene terephthalate (PET) layer configured to be ablated by the beam, forming a microstructure in the surface of the layer. The microstructure may be randomized and used to present non-chroma visual effects.

An apparatus for producing an optically variable film includes a laser configured to emit a beam, a telescoping lens section having a first lens and a second lens spaced apart by a first distance and an interferometer configured to direct the beam toward a workpiece. The laser may be operated at a predetermined power level and the first and second lenses are sized and spaced relative to one another to direct the beam onto the workpiece at about 200-230 dots per inch. The workpiece may include a polyethylene terephthalate (PET) layer configured to be ablated by the beam, forming a microstructure in the surface of the layer. The microstructure may be randomized and used to present non-chroma visual effects.

The present disclosure discloses a method and apparatus for preparing a femtosecond optical filament interference direct writing volume grating/chirped volume grating. The method is characterized in that optical filaments are formed in glass by using femtosecond pulse laser, and plasma is controlled to quickly scan in the glass and etch a volume grating or chirped volume grating structure by adjusting the focal length of convex lens, laser energy and movement of motor machine. The apparatus includes a femtosecond pulse laser module, a pulse chirp management module, a pulse time domain shaping module, a laser separation and interference module, a glass volume grating processing platform module and a camera online imaging module.

The electronic card with printed circuit comprises at least one diffraction structure (DS) having a cavity (15) and a diffraction plate (17). In accordance with the invention, the diffraction structure is incorporated in the thickness of the electronic card with printed circuit, the cavity being formed, by removal of material, in the thickness of the electronic card with printed circuit and the diffraction plate being formed in a plate which is arranged on the electronic card with printed circuit and closes the cavity.

The disclosure provides a method for fabricating a metallic optical metasurface having an array of hologram elements. The method includes forming a first copper layer protected with a conducting or dielectric barrier layer over a backplane structure by a damascene process. The first copper layer comprises a plurality of nano-gaps vertically extending from the backplane structure. The plurality of nano-gaps is filled with a dielectric material. The method also includes removing the dielectric material and a portion of the conducting or dielectric barrier layer to expose the portions in the nano-gaps of the first copper layer. The method may further include depositing a dielectric coating layer over the top portion and exposed side portions of the first copper layer to form a protected first copper layer, and filling the gaps with an electrically-tunable dielectric material that has an electrically-tunable refractive index.

A mirror and information image display assembly (300) for a vehicle, a holographic information image display system (300, 106, 104), a vehicle (100) comprising such an assembly, and a method of providing image information to an occupant of a vehicle are disclosed. The assembly has a reflective layer (302) and an image display means (304, 306), for displaying image information to an occupant of the vehicle. The image display means comprises a hologram (304), and a lighting means comprising a light source (306) for illuminating the hologram.

An instrument panel for a motor vehicle is provided. The instrument panel includes an instrument panel surface and a plurality of indicia disposed on the instrument panel surface. The plurality of indicia comprises holographic ink.