摘要:
A process for stretching films is described. The process preferably stretches films in a uniaxial fashion. Preferably, optical films are stretched including multilayer optical films. Other aspects of the invention include a roll of stretched film and an apparatus for stretching films.
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. In the first zone the layers provide a first reflective polarizer characteristic, and in a second zone the layers provide a substantially different reflective polarizer characteristic. The second zone is characterized by at least some of the layers having a reduced birefringence relative to their birefringence in the first zone. In some cases the first reflective polarizer characteristic may have a pass axis that is substantially orthogonal to that of the second reflective polarizer characteristic. The film may have substantially the same thickness in the first and second zones, or a substantially reduced thickness in the second zone relative to the first zone.
摘要:
A light directing film includes a back major surface having light reflection regions and light transmission regions and being planar, and a front major surface opposing the back surface. The front surface is planar and a plurality of lenses is disposed between the front surface and the back surface. At least selected light transmission regions are registered with selected lens elements. A method for forming the light directing film and illuminated signs utilizing the light directing films are also described.
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:
A reflective film includes interior layers arranged to selectively reflect light by constructive or destructive interference, the layers extending from a first zone to a second zone of the film. The film has a first thickness and the interior layers provide a first reflective characteristic in the first zone; the film has a second thickness and the interior layers provide a second reflective characteristic in the second zone. The difference between the first and second reflective characteristics is not substantially attributable to any difference between the first and second thicknesses, which difference may be zero. Rather, the difference in the reflective characteristics is substantially attributable to reduced birefringence of at least some of the interior layers in one zone relative to the other zone. The film may also incorporate absorbing agents to assist in the manufacture or processing of the film. Related methods and articles are also disclosed.
摘要:
Retarder film combinations generally include a retarder film connected to another optical component such that light transmitted by the retarder film can impinge on the optical component, the combination being configured to allow independent patterning of the retarder film and the optical component by selective birefringence reduction. The patterning can change a first light retardation to a third light retardation in a first zone without substantially changing optical characteristics of the optical component in the first zone. The optical component may be a second retarder film having a second light retardation, and the patterning may change the second light retardation to a fourth light retardation, without substantially changing the first light retardation, in a second zone. The optical component may also be a multilayer optical film, or a diffusely reflective optical film having a blended layer of first and second distinct phases.
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. In the first zone the layers provide a first reflective polarizer characteristic, and in a second zone the layers provide a substantially different reflective polarizer characteristic. The second zone is characterized by at least some of the layers having a reduced birefringence relative to their birefringence in the first zone. In some cases the first reflective polarizer characteristic may have a pass axis that is substantially orthogonal to that of the second reflective polarizer characteristic. The film may have substantially the same thickness in the first and second zones, or a substantially reduced thickness in the second zone relative to the first zone.
摘要:
A stretcher for substantially uniaxially orienting a film includes a plurality of gripping members to hold opposing edge portions of the film, paths along which the gripping members travel to stretch the film in a stretching region, and a drive mechanism to convey the film and gripping members along a machine direction. At least a portion of the paths in the stretching region define diverging, curvilinear courses disposed in-plane. The paths are configured such that during the stretching an extent of uniaxial character, U, is between zero and unity and a minimum value of an extent of uniaxial character, U, is at least 0.70 over a final portion of the stretching after achieving a TDDR of 2.5. U is defined as U=(1/MDDR−1)/(TDDR1/2−1), wherein TDDR is greater than 4 at an end of the stretching region.
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 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).