Abstract: A technique and apparatus for detection of infrared radiation emitted from a taggant material sample following the excitation of the sample are described. The decay time of the radiation is a function of the particular taggant being used and so, if the decay characteristic or signature is accurately measured, the particular taggant can be accurately identified. The apparatus comprises an electronic controller (10), a pair (12) of illuminating light-emitting diodes, a photo-detector (14), a first amplifier (16), a three-way sampling switch (18), filter/stores (20)(a-c), second amplifiers (22)(a-c) and an output display (26). The infrared emission is excited by repeatedly illuminating the material for a period of microseconds every few milliseconds using a very intense source of infrared light. This light is supplied by the pair of 940 nm, light-emitting diodes (12). Once this light source has been turned off, the sample continues radiating infrared light for a few milliseconds.

Abstract: A tagging material for the production of electronic identification tags. Shown generally at (10) is a continuous tape of thermoplastic plastics material. The tape (10) comprises a film (12) having on an upper surface a coating (14) of release agent, and on a lower surface a coating (16) of adhesive. Below the adhesive coating 16 is a further film (18) having on its upper surface an antenna (20) and, electrically connected thereto an integrated circuit (22). On a lower surface of film (18) is a coating of pressure sensitive adhesive (24). The integrated circuit (22) is completely encapsulated in a flexible protective layer (26) of non-conductive waterproof material, which is preferably UV-curable, such as polyurethane.

Abstract: A conventional cigarette packet in a transparent film of bi-axially oriented polypropylene (BOPP) with a tear tape for removing the film adhered to the inside of the film. The tear tape bears an indicium which is either hidden or which changes according to the viewing angle when the image is viewed through the film. The image on the tear tape may be scrambled or coded. The overwrap film includes a descrambling or decoding region which reveals the hidden image or renders the image visible when viewed through the overwrap portion, or creates the visual effect of changing the image according to the viewing angle. The descrambling or decoding region typically comprises a diffraction structure, such as a grating, the characteristics of which, such as its pitch, are complementary with the scrambled or coded image and/or with the pitch of any grid or matrix from which the image is composed.

Abstract: A laminate 40 for a tamper-resistant identity document, the laminate comprising: a carrier film (10, FIG. 1) having a first adhesive layer 11 on a surface thereof, the first adhesive layer 11 comprising one or more visible registration features 13; and a cover film (20, FIG. 2b) having a first surface (20a, FIG. 2b) removably bonded to the first adhesive layer 11 and a second surface (20b, FIG. 2b) having a printed security feature 41, 42, 43 and a second adhesive layer (32, FIG. 3b) thereon. The cover film may have a thickness of no greater than 12 microns. The printed security feature may be in predetermined registration with the one or more visible registration features of the first adhesive layer.