Abstract: A brightness enhancement article that includes: (a) a transparent, flexible substrate; (b) a first major surface having an array of prisms with blunted or rounded peaks characterized by a chord width, cross-sectional pitch width, and radius of curvature in which the chord width is equal to about 20-40% of the cross-sectional pitch width and the radius of curvature is equal to about 20-50% of the cross-sectional pitch width; and (c) a second major surface characterized by a plurality of light scattering protrusions. The article has a haze value between about 20-60% and a transmission value no greater than about 94% when measured under conditions in which the first surface has a substantially planar topography.

Abstract: A transflector is described which increases efficiency and brightness under both ambient and supplemental lighting conditions in visual display applications. In one embodiment, the transflector includes a reflective polarizing element that reflects one polarization of light and transmits the other. In an alternate embodiment, the transflector includes a reflective polarizing element and a diffusing element such that the transflector diffusely reflects light of one polarization and transmits the other. The transflector is useful for both reflective and transflective liquid crystal displays.

Abstract: Optical devices such as light pipes which incorporate multilayer optical films in which the refractive indices of two adjacent layers in the thickness direction are substantially matched or are small relative to the difference in refractive indices of said two adjacent layers in an given in-plane direction which is at least 0.05. The multilayer optical film exhibits low absorptivity and can reflect light approaching at shallow angles as well as normal to the film.

Abstract: A transflector is described which increases efficiency and brightness under both ambient and supplemental lighting conditions in visual display applications. In one embodiment, the transflector includes a reflective polarizing element that reflects one polarization of light and transmits the other. In an alternate embodiment, the transflector includes a reflective polarizing element and a diffusing element such that the transflector diffusely reflects light of one polarization and transmits the other. The transflector is useful for both reflective and transflective liquid crystal displays.

Abstract: Optical devices such as light pipes which incorporate multilayer optical films in which the refractive indices of two adjacent layers in the thickness direction are substantially matched or are small relative to the difference in refractive indices of said two adjacent layers in an given in-plane direction which is at least 0.05.

Abstract: A backlight display includes a case having an optical window through which displayed information may be viewed. In addition it includes an electroluminescent panel for providing the backlight. It further includes a structured surface material between the electroluminescent panel and the optical window. The structured surface material has the property of reflecting light entering it while making an angle in a first predetermined group of angles with the axis of the display back to the electroluminescent panel. It further has the property of refracting light entering it while making an angle in a second predetermined group of angles to the axis of the display such that a majority of the light in the second group will exit in an output wedge that is smaller than the input wedge.

Abstract: A multiple layer reflective polarizer 12 is described. This element is placed between and optical cavity 24 and an LCD module 16 to form an optical display. The reflective polarizer reflects some light into the optical cavity 24 where it is randomized and may ultimately emerge with the correct polarization to be transmitted out of the display.

Abstract: Highly efficient diffusely reflecting multilayer mirrors diffusely reflect light incident upon them. Highly efficient diffusely reflecting multilayer polarizers diffusely reflect light of one polarization while diffusely transmitting the other polarization. The diffusely reflecting mirror includes a light diffusing element and a multilayer mirror element. The diffusely reflecting polarizer includes a light diffusing element and a multilayer reflective polarizing element.

Abstract: The present invention includes a structured optical film with variable pitch peaks and/or grooves to reduce the visibility of moire interference patterns and optical displays incorporating one or more layers of the film. The pitch variations can be over groups of adjacent peaks and/or valleys or between adjacent pairs of peaks and/or valleys.

Abstract: A brightness enhancement film has a plurality of linear prisms. The prisms are disposed in pairs, each pair having first and second prisms and each prism has a prism angle and a valley angle. Either the prism angles or the valley angles, but not both, are equal.

Abstract: A brightness enhanced reflective polarizer includes a reflective polarizer and a structured surface material.

Abstract: Highly efficient diffusely reflecting multilayer mirrors diffusely reflect light incident upon them. Highly efficient diffusely reflecting multilayer polarizers diffusely reflect light of one polarization while diffusely transmitting the other polarization. The diffusely reflecting mirror includes a light diffusing element and a multilayer mirror element. The diffusely reflecting polarizer includes a light diffusing element and a multilayer reflective polarizing element.

Abstract: A light directing film including a first surface and a second structured surface. The structured surface includes a repeating pattern of prism zones including at least a first zone having a plurality of prism elements with peaks disposed at a first distance from a reference plane and a second zone having a plurality of prism elements with peaks disposed less than the first distance from a reference plane. The width of the first zone preferably measures less than about 300 microns.

Abstract: The present invention provides a pole light for directing or delivering light in a desired pattern to a surface proximate to the pole light. The present invention also provides a method for lighting a plurality of desired regions on a surface in a precise and predetermined pattern useful, for example, as a traffic management and guidance system.

Abstract: An improved greenhouse comprising a plurality of walls, a light-transmitting roof panel; and an optical system located inside the greenhouse is described. The optical system comprises a plurality of rows of elongate spaced optical panels generally adjacent and extending transversely across the light-transmitting roof panel. Each panel comprises a thin backing portion forming first and second concave, opposite sides, a first light reflecting means including light-reflecting surfaces attached to the first side of the backing and a second light reflecting means including light-reflecting surfaces attached to the second side of the backing such that the light-reflecting surfaces face generally oppositely.Also disclosed is an improved method of growing plants utilizing such a greenhouse construction.

Abstract: A lighting element has a light source positioned so as to provide a beam of light at a grazing angle to a light extractor. The extractor has a plurality linear triangular prism on the side struck by the beam of light. The prisms lie in a smooth arcuate curve.

Abstract: When two hollow tubular light conduits are interconnected at a miter joint, beamed light can be redirected from one of the conduits to the other by a thin transparent prismatic element that is mounted to extend along the plane of the miter joint. When the interconnected conduits are acting as a luminaire, the miter joint can be fully illuminated by the transported light. A luminaire of unlimited length can be obtained by mounting a plurality of lamps and parabolic reflectors along a transparent hollow tubular light conduit and redirecting light from each lamp to be transported along the axis of the conduit in both directions.

Abstract: A light fixture has a housing having an axis and a light source for detecting light into the housing along the housing axis. A first section of the housing occupies a first portion of the housing's perimeter and includes a light guide material. A second section of the housing occupies a second portion of the housing's perimeter and includes light extraction structures and a Fresnel lens for beam shaping.

Abstract: A thin, flexible film made of a transparent polymeric material including a structured surface and an opposite smooth surface, wherein light striking either surface, within certain angular ranges, is totally internally reflected. The structured surface includes a linear array of miniature substantially right angled isosceles prisms arranged side-by-side to form a plurality of peaks and grooves. In addition, the perpendicular sides of the prims make an angle of approximately 45.degree. with the smooth surface, and when the film is curled the smooth surface lies in a smooth continuous arcuate curve without materially affecting the performance of the film. Because of the film's flexibility and its ability to totally internally reflect light, it may be utilized in a variety of ways, for example, as a collector of solar energy or as a light conduit. The performance of the film may be manipulated to permit controlled light leakage.

Abstract: A light extraction film has light extraction structures on one surface and a Fresnel lens for beam shaping on the opposite surface.