摘要:
Techniques are described for forming microlens sheeting having composite images that appear to float with respect to the plane of the sheeting. As one example, a method comprises forming one or more images within a sheeting having a surface of microlenses, wherein at least one of the images is a partially complete image, and wherein each of the images is associated with a different one of the microlenses, wherein the microlenses have refractive surfaces that transmit light to positions within the sheeting to produce a plurality of composite images from the images formed within the sheeting so that each of the composite images appears to float with respect to the plane of the sheeting, and wherein forming the one or more images comprises forming the one or more images such that each of the composite images is associated with a different viewing angle range.
摘要:
A process for making a microlens array or a microlens array masterform comprises (a) providing a photoreactive composition, the photoreactive composition comprising (1) at least one reactive species that is capable of undergoing an acid- or radical-initiated chemical reaction, and (2) at least one multiphoton photoinitiator system; and (b) imagewise exposing at least a portion of the composition to light sufficient to cause simultaneous absorption of at least two photons, thereby inducing at least one acid- or radical-initiated chemical reaction where the composition is exposed to the light, the imagewise exposing being carried out in a pattern that is effective to define at least the surface of a plurality of microlenses, each of the microlenses having a principal axis and a focal length, and at least one of the microlenses being an aspherical microlens.
摘要:
A method for forming a color shifting film on a support, the film comprising a reflective stack disposed adjacent to the support and an image is disclosed. The reflective stack comprises an at least partially transparent spacer layer comprising a substituted acrylamide polymer disposed between a partially reflective first layer and a reflective second layer. The acrylamide layer has a thickness sufficient to produce an interference color.
摘要:
A reflective film includes a first optical stack that provides a first reflective characteristic and a second optical stack that provides a second reflective characteristic. The optical stacks also have first and second absorptive characteristics that are suitable to absorptively heat the respective stacks upon exposure to light including a write wavelength while maintaining the structural integrity of the stacks. The absorptive heating can change the first and second reflective characteristics to third and fourth reflective characteristics, respectively. A blocking layer that at least partially blocks light of the write wavelength may also be provided between the optical stacks to permit absorptive heating of any selected one of the optical stacks. The reflective characteristics of the optical stacks can thus be independently modified in any desired patterns by appropriate delivery of light beams that include the write wavelength.
摘要:
A reflective film includes interior layers that selectively reflect light by constructive or destructive interference, the layers extending from a first to a second zone of the film. The interior layers include a first set of layers composed of a first material and a second set of layers composed of a different second material. The first and second sets of layers are both birefringent in the first zone, but at least some of the layers have reduced birefringence in the second zone. The reduced birefringence produces a second reflective characteristic in the second zone that differs from a first reflective characteristic in the first zone, this difference not being substantially attributable to any thickness difference between the first and second zones. The film may also incorporate absorbing agents to assist in the manufacture or processing of the film.
摘要:
Laser-personalizable security articles include multi-layer security documents. The multi-layer security document includes an optically transparent cover layer, a composite image and an imagable layer adjacent to the cover layer. The first surface of the cover layer is at least partially a microstructured surface, where the microstructured surface forms microlenses or a lenticular surface. The composite image is made by a collection of complete or partial images viewed through the microstructured surface of the cover layer. The composite image is located on or within the second surface of the cover layer. The imagable layer is a laser imagable layer. When imaged, a personalized second composite three dimensional image is created on or in the imagable layer.
摘要:
A retarder film provides a first light retardation and can be heat processed in one or more selected areas to provide a second light retardation in the selected area(s). The retarder film may have an absorption characteristic such that the heat processing can be carried out by selectively exposing the film to a suitable radiant beam. The retarder film is composed of a stack of contiguous ultrathin layers configured to provide an effective optical medium for visible light. Visible light propagates through the stack as an effective medium having effective refractive indices along principal x-, y-, and z-axes. At least some of the ultrathin layers possess intrinsic birefringence, and the effective indices of the stack are functions of the intrinsic refractive indices of the constituent ultrathin layers. The heat processing is carried out so that the ultrathin layer stack structural integrity is not substantially altered in the processed area(s).
摘要:
Multi-layer articles are described that are capable of forming color images. The articles include at least six layers, four thermally activatable layers (layers 1-4) and two blocking layers (layer 5 and 6). The layers are arranged such that layer 5 is disposed between layers 1 and 2 and layer 6 is disposed between layers 3 and 4. Thermally activatable layers 1 and 2 are activatable upon exposure to light of a first write wavelength, and blocking layer 5 is adapted to at least partially block light of the first write wavelength. Thermally activatable layers 3 and 4 are activatable upon exposure to light of a second write wavelength, and blocking layer 6 is adapted to at least partially block light of the second write wavelength. At least one, and possibly all of the thermally activatable layers include a light to heat convertor composition and a color changing compound. Some of the thermally activatable layers may be a group of layers arranged to selectively reflect light by constructive or destructive interference to provide a first reflective characteristic, the group of layers also having a first absorption characteristic suitable to, upon exposure to light comprising a write wavelength, absorptively heat the first group of layers by an amount sufficient to change the first reflective characteristic to a second reflective characteristic while maintaining the structural integrity of the group of layers.
摘要:
Multi-layer articles are described that are capable of forming color images. The articles may contain at least two layers, a thermally activatable layer and a blocking layer, or at least three layers with two thermally activatable layers and a blocking layer between. The thermally activatable layers absorb light of a write wavelength and have an absorption threshold for activation. The blocking layer blocks light of the write wavelength at certain incident angles or polarization states and permits light of the write wavelength and certain incident angles or polarization states to pass through. The thermally activatable layers may be layers with a light to heat convertor composition and a color changing compound or they may be a group of layers arranged to change its reflective characteristic upon exposure to light while maintaining the structural integrity of the group of layers
摘要:
Certain patternable reflective films are used as masks to make other patterned articles, and one or more initial masks can be used to pattern the patternable reflective films. An exemplary patternable reflective film has an absorption characteristic suitable to, upon exposure to a radiant beam, absorptively heat a portion of the film by an amount sufficient to change a first reflective characteristic to a different second reflective characteristic. The change from the first to the second reflective characteristic is attributable to a change in birefringence of one or more layers or materials of the patternable film. In a related article, a mask is attached to such a patternable reflective film. The mask may have opaque portions and light-transmissive portions. Further, the mask may have light-transmissive portions with structures such as focusing elements and/or prismatic elements.