A security document comprises a substrate (1) and an optical waveguide (7). Couplers (10a, 10b) are provided in the waveguide (7) for coupling light into and out of the waveguide. The couplers (10a, 10b) can e.g. by gratings, scattering objects, holograms, luminescent dyes or perforations. The authenticity of the document can be verified using methods based on the properties of the waveguide.

A method of producing an apparent etched or embossed effect in a print purely by the use of printing and lamination processes, in which a varnish 3 is pressed into to selected areas of a softer coating 2 to produce indentations in the coating layer 2 as during lamination of a printed article comprising a substrate 1 and an optional overlay 4, and a printed article obtainable using the method.

The invention relates to a method of aligning magnetic flakes, which includes: coating a substrate with a carrier having the flakes dispersed therein, moving the substrate in a magnetic field so as to align the flakes along force lines of the magnetic field in the absence of an effect from a solidifying means, and at least partially solidifying the carrier using a solidifying means while further moving the substrate in the magnetic field so as to secure the magnetic flakes in the carrier while the magnetic field maintains alignment of the magnetic flakes. An apparatus is provided, which has a belt for moving a substrate along a magnet assembly for aligning magnetic flakes. The apparatus also includes a solidifying means, such as a UV- or e-beam source, and a cover above a portion of the magnet assembly for protecting the flakes from the effect of the solidifying means.

The invention relates to a card-shaped data carrier (1) comprising a card body (2) provided with a graphical element (6) displayed thereon. The card body (2) is made of a plastic material for converting irradiated light into secondary light and for retransmitting the secondary light within the plastic material to the graphical element (6) or to a portion of the graphical element (6). The inventive card-shaped data carrier (1) is characterized in that the card body (2) is provided with a light source (18) for irradiating light into a shaped body (12) formed by the plastic material.

A surveillance system comprising an electronic identity card holder 100 and corresponding identity card 170. The card holder 100 comprises a slot 150 for receiving an identity card 170. The slot 150 has a first side 150a and an opposing second side 150b. The first side 150a of the slot 150b comprising a viewing window 140 positioned to allow viewing of the second side 150b of slot 150. The card holder 100 also has a camera housed within the holder 100, and the camera has a camera aperture 196 provided on the second side 150b of the slot 150. The corresponding identity card 170 comprises an optically transparent region 175 that is configured to overlie the camera aperture 196 when the identity card 170 is received in the slot 150 of the holder 100.

Disclosed herein is an optical device having a light source, a viscoelastic lightguide and a retroreflective film suitable for retroreflecting light. Light from the light source enters the viscoelastic lightguide and is transported within the lightguide by total internal reflection. The transported light is extracted from the lightguide and retroreflected at a structured surface of the retroreflective film. The optical device may have a front lit or a back lit configuration depending on the relative positioning of the lightguide and the retroreflective film. The retroreflective film may include prismatic retroreflective sheeting, holographic film or film structured with diffraction gratings. The optical device may be used, for example, as a sign or marking, a license plate assembly, a tail light assembly for vehicles, a security laminate for protection of documents against tampering, or an illumination device.