Abstract: Optical films for redirecting light are described, and optical systems, such as display systems, incorporating such optical films are described. The optical film may include a first structured surface including a plurality of prismatic structures, and a second structured surface opposing the first structured surface and including a plurality of microstructures. An effective transmission of the optical film is not more than 1% less than a film with a comparable construction except for a smooth, non-structured second surface.

Abstract: According to one embodiment, a method of making an optical film for control of light comprising: positioning a first mixture on a substrate, wherein the first mixture comprises a first plurality of magnetizable particles dispersed in a first resin, assembling the first plurality of magnetizable particles into a desired structure for the control of the light by rotating modulation of at least a first magnetic field relative to the first plurality of magnetizable particles, and vitrifying the first resin while the first plurality of magnetizable particles are in the desired structure.

Abstract: An optical element including an array of microlenses, a pinhole mask, and a wavelength selective filter is described. The pinhole mask includes an array of pinholes with each pinhole in the array of pinholes aligned with a microlens in the first array of microlenses. The wavelength selective filter is adapted to transmit a first light ray having a first wavelength and transmitted from a first microlens in the array of microlenses through a first pinhole in the array of pinholes aligned with the first microlens, and to attenuate a second light ray having the first wavelength and transmitted from the first microlens through a second pinhole in the array of pinholes aligned with a second microlens in the first array of microlenses adjacent to the first microlens.

Abstract: A unitary optical film stack comprising a light redirecting film assembly; a light diffusion film assembly; and an optical adhesive; wherein the light redirecting film assembly and the light diffusion film assembly are physically coupled non-continuously to minimize optical coupling.

Abstract: An optical film having a first surface, an opposing second surface, and a thickness normal to the first and second surfaces is cut. Cutting the film forms a channel at least partially through the thickness of the film. A light control material is printed proximate to a surface of the film. The ink traverses through the channel by capillary motion.

Abstract: A microstructured diffuser is described comprising a light transmissive film comprising a first microstructured surface comprising a plurality of peaks and valleys. A coating is disposed on the first microstructured surface. The coating partially fills the valleys forming a second microstructured surface.

Abstract: An optical film assembly comprises a light redirecting film (110) having a first structured major surface (112) and a second, opposed major surface (114). An optical adhesive layer (120) is disposed on the second major surface of the light redirecting film. A light diffusion film (140) comprises a first major surface (142) comprising a light diffusion surface and a second, opposed major surface (144). A plurality of discrete optical decoupling structures (146) project from the light diffusion surface and contact the optical adhesive layer. An air gap (148) is defined between the first major surface of the light diffusion film and the optical adhesive layer. Embodiments of optical film assemblies described herein are useful, for example, for hiding optical defects and improving the brightness uniformity of light emitted by a light source.

Abstract: An optical film assembly comprising a first optical film, a coupling member, and a second optical film wherein the first optical film comprises a prismatic film, the second optical film comprises a diffuser, wherein the coupling member is bonded to the first optical film and to the second optical film such that the first optical film and second optical film are physically coupled, and the coupling member is bonded to at least one of the first optical film and the second optical film non-continuously such that an optically effective air gap is provided. Also, a method for making such optical film assemblies.

Abstract: A diffuser including opposing structured first and second major surfaces is described. The first major surface includes a first plurality of surface structures providing a uniform first haze. The second major surface includes a first portion adjacent an edge and a second portion adjacent the first portion. The first portion includes a first region and a second region between the first region and the second portion. The second major surface includes a second plurality of surface structures providing a uniform second haze over the second portion and providing a third haze in the first portion. The third haze in the first region is higher than the second haze, and the third haze in the second region is monotonically decreasing. The second portion has a surface area of at least 90 percent of a surface area of the second major surface.

Abstract: An optical film includes a microstructured surface having a plurality of irregularly arranged planar portions forming greater than about 10% of the microstructured surface. The microstructured surface may be configured such that, when the microstructured surface is placed on an emission surface of a lightguide with a first luminous distribution of light exiting the lightguide from the emission surface in a first plane perpendicular to the emission surface, the light emitted by the lightguide is transmitted by the microstructured surface at a second luminous distribution of the transmitted light in the first plane. The first luminous distribution includes a first peak making a first angle greater than about 60 degrees with a normal to the microstructured surface. The second luminous distribution includes a second peak making a second angle in a range from about 5 degrees to about 35 degrees with the normal to the microstructured surface.

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: 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: An optical film (210) includes a microstructured surface (211) comprising a plurality of prismatic structures (230), the microstructured surface (211) defining a reference plane (241-242) and a thickness direction (243) perpendicular to the reference plane; wherein the plurality of prismatic structures includes a plurality of facets (231), each facet having a facet normal direction forming a polar angle with respect to the thickness direction and an azimuthal angle along the reference plane, and wherein the microstructured surface has a surface azimuthal distribution of the plurality of facets that is substantially uniform, and wherein the microstructured surface has a surface polar distribution of the plurality of facets that has an off-axis peak polar distribution.

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: 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: 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: Optical films for redirecting light are described, and optical systems, such as display systems, incorporating such optical films are described. The optical film may include a first structured surface including a plurality of prismatic structures, and a second structured surface opposing the first structured surface and including a plurality of microstructures. An effective transmission of the optical film is not more than 1% less than a film with a comparable construction except for a smooth, non-structured second surface.

Abstract: An optical film having a structured surface is described. At least 90% of the structured surface has a slope magnitude that is less than about 5 degrees. The optical film may have an optical haze of less than about 10% and an optical clarity of less than about 50%, or may have an optical haze of less than about 7.5% and an optical clarity of less than about 60%, or may have an optical haze of less than about 3% and an optical clarity of less than about 65%.

Abstract: An optical film assembly comprising a first optical film, a coupling member, and a second optical film wherein the first optical film comprises a prismatic film, the second optical film comprises a diffuser, wherein the coupling member is bonded to the first optical film and to the second optical film such that the first optical film and second optical film are physically coupled, and the coupling member is bonded to at least one of the first optical film and the second optical film non-continuously such that an optically effective air gap is provided. Also, a method for making such optical film assemblies.

Abstract: A diffuser including opposing structured first and second major surfaces is described. The first major surface includes a first plurality of surface structures providing a uniform first haze. The second major surface includes a first portion adjacent an edge and a second portion adjacent the first portion. The first portion includes a first region and a second region between the first region and the second portion. The second major surface includes a second plurality of surface structures providing a uniform second haze over the second portion and providing a third haze in the first portion. The third haze in the first region is higher than the second haze, and the third haze in the second region is monotonically decreasing. The second portion has a surface area of at least 90 percent of a surface area of the second major surface.