Abstract: The present disclosure describes light delivery and distribution components of a ducted lighting system having a cross-section that includes at least one curved portion and a remote light source. The delivery and distribution system (i.e., light duct and light duct extractor) can function effectively with any light source that is capable of delivering light which is substantially collimated about the longitudinal axis of the light duct, and which is also preferably substantially uniform over the inlet of the light duct.

Abstract: Brightness enhancing films with embedded diffusers are described. More specifically, films including a birefringent substrate, a prismatic layer carried by the substrate having linear prisms, and an embedded structured surface disposed between the substrate and the prismatic layer are disclosed. The embedded structured surface may include closely-packed structures. Processes for producing embedded structured surfaces having particular topographies are also disclosed.

Abstract: A brightness enhancement film includes a plurality of linear prisms disposed on a birefringent substrate. A light ray that enters the film from the substrate side and exits the film from the linear prisms side undergoes substantially a same phase retardation for mutually orthogonal polarization states while travelling within the film. The light ray exits the film at an angle from a normal to the substrate that is greater than 20 degrees.

Abstract: Optical diffusing films are made by microreplication from a structured surface tool. The tool is made using a 2-part electroplating process, wherein a first electroplating procedure forms a first metal layer with a first major surface, and a second electroplating procedure forms a second metal layer on the first metal layer, the second metal layer having a second major surface with a smaller average roughness than that of the first major surface. The second major surface can function as the structured surface of the tool. A replica of this surface can then be made in a major surface of an optical film to provide light diffusing properties. The structured surface and/or its constituent structures can be characterized in terms of various parameters such as optical haze, optical clarity, Fourier power spectra of the topography along orthogonal in-plane directions, ridge length per unit area, equivalent circular diameter (ECD), and/or aspect ratio.

Abstract: A backlight system includes an extended area light guide (120) and crossed first (128) and second (130) prismatic recycling films. The light guide provides a first light distribution that has a maximum luminance at a first polar angle, e.g., from 70 to 90 degrees, relative to the optical axis (116) of the system. The recycling films provide a second light distribution. No diffuser film is provided between the light guide and the recycling film disposed nearest the light guide. Instead, light is specularly transmitted from the output surface (120a) of the light guide to the input surface (128a) of the recycling film nearest the light guide. The recycling films comprise prisms having refractive indices tailored to provide the second light distribution with a maximum luminance at a polar angle of 10 degrees or less. The prisms preferably have a refractive index from 1.63 to 1.76. Related methods and articles are also disclosed.

Abstract: A microreplicated optical film (919) for use in optical displays, backlights, and the like includes a prismatic layer (950) carried by a substrate (920). In use, the optical film may be combined in a system with other components such that the optical film is positioned between an extended light source (902) and a polarizer (904). In such cases, if the substrate has an appreciable birefringence, a subtle but characteristic colored pattern known as substrate color mura (SCM) may be detected by a user of the system. To reduce or eliminate the SCM with little or no adverse effect on brightness enhancement capabilities of the optical film, the optical film may include an embedded structured surface (933) between the substrate and the prismatic layer. In order to avoid another optical artifact known as sparkle, at least 80% of the embedded structured surface is preferably occupied by features such as defocusing lenslets or random planar facets.

Abstract: A display system includes a switchable display screen comprising a first transparent substrate, a first transparent conductive layer disposed upon the first transparent substrate, a second transparent substrate, and a second transparent conductive layer disposed upon the second transparent substrate. The display screen further includes a polymer-stabilized cholesteric texture layer and spacer elements disposed between and in contact with the first transparent conductive layer and the second conductive layer. The display screen comprises a plurality of addressable regions, each region capable of being switched from a transparent state to a diffuse state.

Abstract: Example light management films including a plurality of tapered protrusions are described. In many embodiments, a film includes a reflective polarizer layer and a plurality of tapered protrusions disposed on and tapering away from the reflective polarizer layer. At least one tapered protrusion in the plurality of tapered protrusions has a first lateral cross-section at a first location along a height of the tapered protrusion and a second lateral cross-section at a second location along the height of the tapered protrusion. The first cross-section has a first shape and the second cross-section has a different second shape.

Abstract: Example light management films are described. In one example, an optical stack comprises a first light directing film comprising a structured major surface opposite a second major surface, the structured major surface comprising a plurality of linear structures extending along a first direction, the light directing film having an average effective transmission of at least 1.3; and an asymmetric light diffuser disposed on the light directing film and being more diffusive along a second direction and less diffusive along a third direction orthogonal to the second direction, the second direction making an angle with the first direction that is greater than zero and less than 60 degrees.

Abstract: Lightguide is disclosed. The lightguide includes a light guiding layer for propagating light by total internal reflection, and an optical film that is disposed on the light guiding layer. The optical film includes a plurality of voids, an optical haze that is not less than about 30%, and a porosity that is not less than about 20%. Substantial portions of each two neighboring major surfaces in the lightguide are in physical contact with each other.

Abstract: A brightness enhancement film includes a plurality of linear prisms disposed on a birefringent substrate. A light ray that enters the film from the substrate side and exits the film from the linear prisms side undergoes substantially a same phase retardation for mutually orthogonal polarization states while travelling within the film. The light ray exits the film at an angle from a normal to the substrate that is greater than 20 degrees.

Abstract: Lightguides are disclosed. More particularly, lightguides that include a lightguiding layer and a light extracting layer having a structured surface are disclosed. The light guiding layer is optically coupled to a first set of structures of the structured surface at given locations, and is not optically coupled to a second set of structures at given locations, thereby producing total internal reflection at the second locations. The selective optical coupling may be achieved by a number of different contemplated means as discussed herein. The lightguides allow for distribution of light along with redirection towards an image viewer without a number of commonly required optical elements in backlights.

Abstract: Example light management films including a plurality of tapered protrusions are described. In some examples, the disclosure relates to a film comprising a reflective polarizer layer and a plurality of tapered protrusions disposed on and tapering away from the reflective polarizer layer, where the tapered protrusions include at least one of a plurality of substantially conical shaped protrusions or a plurality of pyramidal shaped protrusions including at least four side faces. The plurality of tapered protrusions may be configured to reduce the divergence of incident light and redirect a majority of incident light propagating along a first direction to a second direction different from the first direction.

Abstract: Superhydrophobic films (200, 400) are disclosed. More particularly, durable superhydrophobic films (200, 400) having discrete flat faces (206, 406) spaced apart by valleys (208, 408) where the valleys and faces are covered by nanostructures or nanoparticles (424) are disclosed. Various methods of making such films are also disclosed.

Abstract: Lightguides are disclosed. More particularly, lightguides that include a lightguiding layer and a light extracting layer having a structured surface are disclosed. The light guiding layer is optically coupled to a first set of structures of the structured surface at given locations, and is not optically coupled to a second set of structures at given locations, thereby producing total internal reflection at the second locations. The selective optical coupling may be achieved by a number of different contemplated means as discussed herein. The lightguides allow for distribution of light along with redirection towards an image viewer without a number of commonly required optical elements in backlights.

Abstract: A lightguide (3690) is disclosed. The lightguide includes a light guiding layer (3610) for propagating light by total internal reflection, and an optical film (3640) that is disposed on the light guiding layer. The optical film includes a plurality of voids, an optical haze that is not less than about 30%, and a porosity that is not less than about 20%. Substantial portions of each two neighboring major surfaces (3614, 3642) in the lightguide are in physical contact with each other. The lightguide can be used as blacklight in a display system.

Abstract: A backlight system includes an extended area light guide (120) and crossed first (128) and second (130) prismatic recycling films. The light guide provides a first light distribution that has a maximum luminance at a first polar angle, e.g., from 70 to 90 degrees, relative to the optical axis (116) of the system. The recycling films provide a second light distribution. No diffuser film is provided between the light guide and the recycling film disposed nearest the light guide. Instead, light is specularly transmitted from the output surface (120a) of the light guide to the input surface (128a) of the recycling film nearest the light guide. The recycling films comprise prisms having refractive indices tailored to provide the second light distribution with a maximum luminance at a polar angle of 10 degrees or less. The prisms preferably have a refractive index from 1.63 to 1.76. Related methods and articles are also disclosed.

Abstract: A liquid crystal device comprises of a pair of opposed substrates defining a cell gap. Each substrate has an electrode disposed on a surface facing the other substrate. A plurality of spacers are randomly disposed in the cell gap and extend from one substrate to the other substrate, wherein a polymerization enhancing or initiating compound is not disposed on the surface of the spacers. Polymer columns are randomly disposed between the opposed substrates, extending from one substrate to the other, at least a portion of which are disposed around and immobilize the spacers in the cell gap. A liquid crystal material is disposed in the cell gap. A method for making a liquid crystal device is also provided. The internal columnar structures provide stability against mechanical pressure enabling the fabrication of durable, flexible LC display devices using plastic substrates for applications in portable and handheld devices.

Abstract: An apparatus (10, 10?) for producing an alignment surface on an associated substrate (12, 12?) of a liquid crystal display. An electron source (40) produces a collimated electron beam (50). A substrate support (20, 20?) supports the associated substrate (12, 12?) with a surface normal (80) of the substrate arranged at a preselected angle (?) relative to the collimated electron beam (50). The collimated electron beam (50) is rastered across the associated substrate (12, 12?) at the preselected angle (?) while the substrate moves through the electron beam.

Abstract: A liquid crystal device comprises of a pair of opposed substrates defining a cell gap. Each substrate has an electrode disposed on a surface facing the other substrate. A plurality of spacers are randomly disposed in the cell gap and extend from one substrate to the other substrate, wherein a polymerization enhancing or initiating compound is not disposed on the surface of the spacers. Polymer columns are randomly disposed between the opposed substrates, extending from one substrate to the other, at least a portion of which are disposed around and immobilize the spacers in the cell gap. A liquid crystal material is disposed in the cell gap. A method for making a liquid crystal device is also provided. The internal columnar structures provide stability against mechanical pressure enabling the fabrication of durable, flexible LC display devices using plastic substrates for applications in portable and handheld devices.