Abstract:
Disclosed herein is an optical device having a light source, a viscoelastic lightguide and a retroreflective film suitable for retroreflecting light. Light from the light source enters the viscoelastic lightguide and is transported within the lightguide by total internal reflection. The optical device may have a “front lit” configuration such that light being transported within the lightguide is extracted and retroreflected by the film toward a viewer. The optical device may have a “back lit” configuration such that light being transported within the lightguide is extracted and transmitted through the film toward a viewer. The retroreflective film may comprise beaded retroreflective sheeting such as that used in traffic signs and markings.
Abstract:
A display film includes a transparent polymeric substrate layer and a transparent aliphatic cross-linked polyurethane layer disposed on the transparent polymeric substrate layer. The transparent aliphatic cross-linked polyurethane layer has a glass transition temperature in a range from 11 to 27 degrees Celsius and a Tan Delta peak value in a range from 0.5 to 2.5. The display film has a haze value of 1% or less.
Abstract:
A display film includes a transparent polymeric substrate layer and a transparent aliphatic cross-linked polyurethane layer disposed on the transparent polymeric substrate layer. The transparent aliphatic cross-linked polyurethane layer has a glass transition temperature in a range from 11 to 27 degrees Celsius and a Tan Delta peak value in a range from 0.5 to 2.5. The display film has a haze value of 1% or less.
Abstract:
Variable index light extraction layers (100) that contain a plurality of microreplicated posts (120) are described. The variable index light extraction layers contain a plurality of microreplicated posts (120), a first region including a first lower-index substance (130) and a second region including a second higher-index substance (140). Optical films can use the variable index light extraction layers (100) in front lit or back lit display devices.
Abstract:
Cover tapes for securing electronic parts in a carrier tape are provided. The cover tape includes opposing edges extending along a longitudinal direction of the cover tape orthogonal to a transverse direction, and first and second layers. The first layer is stretch-oriented along the longitudinal direction at a first stretch ratio, and the first and second layers are stretch-oriented along the transverse direction at a second stretch ratio greater than the first stretch ratio. The cover tape further includes a first major surface extending along the longitudinal direction and between the opposing edges, the first major surface including a plurality of linear depressions extending along the longitudinal direction. The cover tape is hand-tearable along each linear depression. Also, assemblies and methods for making cover tapes are provided.
Abstract:
Optical devices include a light source and an optical article, where the optical article is an acid-free, non-yellowing pressure sensitive adhesive light guide. The light source is optically coupled to the light guide such that light emitted by the light source enters the light guide and is transported within the light guide by total internal reflection. The light guide includes a plurality of features oriented to extract light being transported within the light guide.
Abstract:
Hybrid signage capable of self illumination and having an active backlight. The signage includes a turning film having a structured surface for redirecting light in order to passively illuminate a printed graphic or shaped sign when the backlight is off. In the shaped sign, the shape provides the content, such as letters, to be conveyed to the viewer instead of a graphic. The signage can be actively illuminated when the backlight is on to supplemental the passive illumination.
Abstract:
Heat de-bondable optical articles include two optical substrates and a heat de-bondable adhesive article disposed between them. The adhesive article includes a heat-shrinkable substrate and an optically clear adhesive proximate to the heat-shrinkable substrate. Optical articles can be prepared by disposing the heat-shrinkable substrate and the optically clear adhesive between two optical substrates. The optically clear adhesive covers a majority of the surface area of the optical substrates, and the heat-shrinkable substrate is located near the edge of the optical substrates.
Abstract:
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.