摘要:
A diffractive optical element (DOE) and various methods of producing such a DOE are provided in which a diffractive optical microstructure is formed with encrypted data on at least one side of a transparent substrate or in a layer applied to the substrate. The diffractive optical microstructure when illuminated with collimated light, generates a far field interference pattern corresponding to the encrypted data which may be decrypted with suitable optical detectors and processing equipment.
摘要:
A method of producing a personalized security document or article includes providing a substrate which is transparent at least to visible light. A diffractive optical microstructure is formed in a substantially opaque layer disposed on a surface of the substrate. The diffractive structure comprises a plurality of apertures formed in the opaque layer, such that when the structure is suitably illuminated, for example by a beam of collimated light, a projected image is generated which is unique to a particular individual. Also, personalized security documents or articles made in accordance with the method.
摘要:
A method of producing a security document or article including a substrate (100), which is transparent at least to visible light, and a diffractive optical microstructure (112). The method includes applying an opacifying layer (102) to at least one surface of the transparent substrate (100). An area of the opacifying layer (102) is exposed to laser radiation (108) to ablate apertures (110) in selected portions of the opacifying layer (102), thereby forming a diffractive optical microstructure (112) on the surface of the substrate (100). The laser radiation may be patterned prior to exposing the opacifying layer (102), for example by passing the radiation through a mask (104). Alternatively, a focussed or collimated laser beam (206) may be directed onto the selected portions of the opacifying layer (102). Laser radiation may be directed onto the opacifying layer (102) either directly, or through the transparent substrate (100). Security documents or articles made in accordance with the method are also provided.
摘要:
Various methods of producing a security document or article including a diffractive optical microstructure are disclosed. One method includes applying an opacifying layer (102) to at least one surface of a transparent substrate (100). An area of the opacifying layer (102) is exposed to laser radiation (108) to ablate apertures (110) in selected portions of the opacifying layer (102), thereby forming a diffractive optical microstructure (112) on the surface of the substrate (100). The laser radiation may be patterned prior to exposing the opacifying layer (102), for example by passing the radiation through a mask (104). Alternatively, a focussed or collimated laser beam (206) may be directed onto the selected portions of the opacifying layer (102). Laser radiation may be directed onto the opacifying layer (102) either directly, or through the transparent substrate (100). Security documents or articles made in accordance with the method are also provided.
摘要:
A security document and a method of manufacturing a security document are provided in which a radiation curable ink is applied to at least one side of a substrate including at least one region of transparent plastics material forming a window or half-window area. The ink is embossed while soft and cured with radiation to form an embossed security device within the window or half-window area including one or more of a diffractive structure, a lens structure or other security element having a relief structure.
摘要:
A method and apparatus for inspection of a security article (10) is provided in which a substantially collimated light beam (15) from a point light source (14) is directed onto a diffractive optical projection element (DOE) (11). The light beam is transformed by the DOE (11) into a patterned beam (17) which is reconstructed to form a projected image at a particular position in space remote from the surface of the security article 910). An optical detection device 916) is located at which the patterned beam (17) is reconstructed to detect the projected image. The inspection method and apparatus may be used in equipment for handling, sorting, counting or otherwise processing security articles, in particular security documents such as banknotes. The apparatus may include a processor for generating a signal when the absence or poor quality of a DOE is detected and which is used to isolate or mark the security article.
摘要:
A security document and a method of manufacturing a security document are provided in which a radiation curable ink is applied to at least one side of a substrate including at least one region of transparent plastics material forming a window or half-window area. The ink is embossed while soft and cured with radiation to form an embossed security device within the window or half-window area including one or more of a diffractive structure, a lens structure or other security element having a relief structure.
摘要:
A security document (1) is provided having a substrate (4) and an integral security device (10) which includes an image layer (12) and a focussing layer (11). each formed from a radiation curable ink layer embossed with relief formations (13; 15). The first radiation curable layer embossed with relief formations (13) to form the image layer (12) is provided on a first surface of the document, and the second radiation curable layer (11) embossed with focussing element relief formations (15) is provided on a second surface of the document. The first and second surfaces are separated by a predetermined distance D to produce a visible optical effect when viewing the image layer (12) through the focussing layer (11). In preferred embodiments, at least one of the first and second radiation curable layers is embossed with diffractive relief structures and high refractive index or reflective coatings may be applied to the embossed relief formations in the image layer (12) and/or the focussing layer (11). The invention allows security devices to be integrated in a security document, such as a banknote, in a cost-effective manner, without substantially increasing the thickness of the document.
摘要:
A security document or device is provided which incorporates one or more optical components. Each component includes at least one orientating layer, preferably a photo-orientated polymer network (PPN), and at least one liquid crystal polymer (LCP) layer, and either or both of the orientating layers and LCP layers include a cross-linker to improve the robustness of the document or device without detracting from the desired optical properties. Such a document or device can be authenticated using an external polariser, or using a polariser integral to the document or device itself.
摘要:
A method and apparatus for inspection of a security article (10) is provided in which a substantially collimated light beam (15) from a point light source (14) is directed onto a diffractive optical projection element (DOE) (11). The light beam is transformed by the DOE (11) into a patterned beam (17) which is reconstructed to form a projected image at a particular position in space remote from the surface of the security article 910). An optical detection device 916) is located at which the patterned beam (17) is reconstructed to detect the projected image. The inspection method and apparatus may be used in equipment for handling, sorting, counting or otherwise processing security articles, in particular security documents such as banknotes. The apparatus may include a processor for generating a signal when the absence or poor quality of a DOE is detected and which is used to isolate or mark the security article.