摘要:
This application describes a front-lit reflective display assembly including a reflective display and an illumination article for front-lighting the display when the article is optically coupled to a light source. The illumination article includes a variable index light extraction layer optically coupled to a lightguide. The variable index light extraction layer has first and second regions, the first region comprising nanovoided polymeric material, the second region comprising the nanovoided polymeric material and an additional material, the first and second regions being disposed such that for light being transported at a supercritical angle in the lightguide, the variable index light extraction layer selectively extracts the light in a predetermined way based on the geometric arrangement of the first and second regions. Front-lit reflective display devices including the front-lit reflective display assembly optically coupled to a light source are also described.
摘要:
Direct-lit backlights and associated methods and components are disclosed in which a transflector that partially transmits and partially reflects incident light is shaped to form at least one concave structure facing a back reflector of the backlight. This provides at least one recycling cavity therebetween, the at least one recycling cavity substantially filling the output area of the backlight. At least one light source is disposed behind the output area to inject light into each cavity, and can be positioned in the recycling cavity or behind an aperture in the back reflector. The cavities are preferably shallow and wide, having a width-to-depth ratio of at least 5 or 10, and can provide uniform brightness and color at the output area with sparsely distributed light sources and in a thin profile backlight.
摘要:
This application describes a back-lit transmissive display including a transmissive display (620) and a variable index light extraction layer (640) optically coupled to a lightguide (630). The variable index light extraction layer has first regions (140) of nanovoided polymeric material and second regions (130) of the nanovoided polymeric material and an additional material. The first and second regions are disposed such that for light being transported at a supercritical angle in the lightguide, the variable index light extraction layer selectively extracts the light in a predetermined way based on the geometric arrangement of the first and second regions. The transmissive display may be a transmissive display panel or a polymeric film such as a graphic.
摘要:
A backlight that includes a front reflector (120) and a back reflector (130) that form a hollow light recycling cavity including an output surface (104) is disclosed. At least a portion of the back reflector is non-parallel to the front reflector. The backlight also includes at least one semi-specular element disposed within the hollow light recycling cavity, and one or more light sources (140) disposed to emit light into the hollow light recycling cavity, where the one or more light sources are configured to emit light into the hollow light recycling cavity over a limited angular range.
摘要:
The present disclosure generally relates to patterned gradient polymer films and methods for making the same, and more particularly to patterned gradient optical films that have regions that include variations in optical properties such as refractive index, haze, transmission, clarity, or a combination thereof. The variation in optical properties can occur across a transverse plane of the film as well as through a thickness direction of the film.
摘要:
A film construction (610) includes a group of microlayers that reflect normally incident light polarized along a first axis more than normally incident light polarized along a second axis. The microlayers are arranged into optical repeat units (ORUs) that have a layer thickness distribution along a thickness axis perpendicular to the first and second axes that provides the group of microlayers with an intermediate reflectivity over an extended reflection band for a given incidence condition. The ORUs include thinner ORUs whose thicknesses are less than an average thickness, and thicker ORUs whose thicknesses are greater than the average thickness. The group of microlayers is optically immersed in a medium having a refractive index greater than air, such that “supercritical light” can propagate through the microlayers. The microlayers are oriented such that, on average, the thinner ORUs are closer than the thicker ORUs to an output surface of the construction. By “supercritical light” is meant that travels through the film at an angle that is more oblique than can be achieved by illumination from air using a flat, smooth air/film interface.
摘要:
Light sources are disclosed. A disclosed light source includes an optically reflective cavity that includes an input port for receiving light and an output port for transmitting light, a lamp that is disposed at the input port, and an optical stack that is disposed at the output port. The optical stack includes a forward scattering optical diffuser that is disposed at the output port and has an optical haze that is not less than about 20%, and an optical film that is disposed on the optical diffuser. The optical film enhance total internal reflection at the interface between the optical film and the optical diffuser. The optical film has an index of refraction that is not greater than about 1.3 and an optical haze that is not greater than about 5%. The optical stack also includes a reflective polarizer layer that is disposed on the optical film. Substantial portions of each two neighboring major surfaces in the optical stack are in physical contact with each other.
摘要:
An edge-lit backlight comprises a front and back reflector forming a hollow light recycling cavity having a cavity depth H and an output region of area Aout, and one or more light sources disposed proximate a periphery of the backlight to emit light into the light recycling cavity. The light sources have an average plan view source separation of SEP collectively having an active emitting area Aemit, wherein a first parameter equals Aemit/Aout and a second parameter equals SEP/H. The first parameter is in a range from 0.0001 to 0.1, and by the second parameter is in a range from 3 to 10. The front reflector has a hemispherical reflectivity for unpolarized visible light of Rfhemi, and the back reflector has a hemispherical reflectivity for unpolarized visible light of Rbhemi, and Rfhemi*Rbhemi is at least 0.70.
摘要:
Optical stack is disclosed. The optical stack includes a first optical stack that includes, a first optical adhesive layer, and a reflective polarizer layer that is disposed on the first optical adhesive layer. The reflective polarizer layer substantially reflects light of a first polarization state and substantially transmits light of a second polarization state orthogonal to the first polarization state. The optical stack also includes a second optical stack that includes a second optical adhesive layer, a low index layer that is disposed on the second optical adhesive layer and includes a plurality of voids dispersed in a binder, and a light directing film that is disposed on the low index layer and includes a plurality of unitary discrete structures. Portions of each unitary discrete structure penetrate into the first optical adhesive layer. Portions of each unitary discrete structure do not penetrate into the first optical adhesive layer. Each unitary discrete structure defines a penetration depth and a penetration base at the interface between the penetrating and non-penetrating portions of the unitary discrete structure. The penetration base has a minimum penetration base dimension. The plurality of unitary discrete structures has an average penetration depth and an average minimum penetration base dimension. The ratio of the average penetration depth to the average minimum penetration base dimension is at least 1.5. The peel strength between the first and second optical stacks is greater than about 30 grams/inch.
摘要:
Optical constructions use a low index of refraction layer (120) disposed between a low absorption layer (101) and a high absorption layer (103) to increase confinement of light to the low absorption region of the optical constructions. Low index layers can be used in optical constructions that have multi-tiered light confinement. In these constructions, a first tier of reflection is provided when light is reflected at the surface of a low index optical film which is disposed directly or indirectly on a light guide (110). A second tier of reflection occurs at the surface of a light redirecting film having appropriately oriented refractive structures.