摘要:
Films having a structured surface with an engineered feature, such as prism grooves, to be used in displays having a backlight. The films can be arranged in a stack having one or more of the following: birefringent brightness enhancement films, non-birefringent brightness enhancement films, polarizers, diffusers, birefringent turning films, and non-birefringent turning films. Those films can be arranged in any order from the backlight to a viewer.
摘要:
An exemplary roll of film includes an oriented optical film comprising a birefringent material characterized by an effective orientation axis and a normalized difference between a refractive index for light polarized along TD and a refractive index for light polarized along ND being less than 0.06. The optical film has a width of greater than 0.3 m and a length a length greater than 10 m, and the effective orientation axis is aligned along the length of the optical film (MD).
摘要:
Exemplary methods include includes providing a film comprising at least one polymeric material; widening the film under a first set of processing conditions in a first draw step along the crossweb direction such that in-plane birefringence, if any, created in the film is low; and drawing the film in a second draw step along a downweb direction, while allowing the film to relax along the crossweb direction, under a second set of processing conditions, wherein the second set of processing conditions creates in-plane birefringence in at least one polymeric material.
摘要:
A backlight (120) that includes a front reflector (130) and a back reflector (160) that form a hollow light recycling cavity (162) having an output surface (164) is disclosed. The front reflector includes at least four directional recycling films (132). The backlight also includes a semi-specular diffuser disposed between the front reflector and the back reflector, and one or more light sources (166) disposed to emit light into the light recycling cavity.
摘要:
A backlight (120) that includes a front reflector (130) and a back reflector (160) that form a hollow light recycling cavity (162) having an output surface (164) is disclosed. The front reflector includes at least four directional recycling films (132). The backlight also includes a semi-specular diffuser disposed between the front reflector and the back reflector, and one or more light sources (166) disposed to emit light into the light recycling cavity.
摘要:
Backlighting systems are disclosed, which include a lightguide with at least one light source optically connected to an edge of the lightguide for supplying light into its interior and a reflective cavity with at least one light source optically connected to the reflective cavity for supplying light into its interior. The reflective cavity may include a first reflector and a second reflector and at least one source may be disposed at an edge of the reflective cavity. Alternatively, the reflective cavity may include a back reflector portion and light sources may be disposed at the back reflector portion.
摘要:
A direct-lit backlight includes a diffuse reflector disposed in front of a light source. The diffuse reflector has a continuous phase material and a disperse phase material, at least one of which is birefringent, and the disperse phase material is formed into particles having a transverse dimension less than 1 micrometer for efficient visible light scattering. The continuous and disperse phases have refractive indices tailored so the diffuse reflector transmits light from the light source substantially more strongly for obliquely incident light than for normally incident light to provide bulb-hiding characteristics.
摘要:
A polarizer construction is disclosed that includes a reflective polarizer disposed on a first side of the construction to transmit light having one polarization and reflect light having an orthogonal polarization, and one or more colored dichroic polarizers disposed on a second side of the construction. The one or more colored dichroic polarizers are arranged so that when the construction is illuminated from the first side, an observer viewing the construction from the second side will observe a first spectral distribution of visible light, and when the construction is illuminated from the second side, an observer viewing the construction from the second side will observe a second spectral distribution of visible light different from the first spectral distribution. Various display constructions using colored polarizers to achieve color changing and image reversal effects are also disclosed.
摘要:
An optical film includes a reflective polarizing element and a particle-containing layer. The reflective polarizing element substantially reflects light having a first polarization state and substantially transmits a second polarization state. The particle-containing layer is disposed on the reflective polarizing element and in a same optical path as the reflective polarizing element. The particle-containing layer is configured and arranged to transmit light and includes a plurality of particles that roughen an exterior surface of the optical film. Preferably, using the optical film in an optical device does not substantially reduce the gain advantage of the optical device when compared with an optical device utilizing the same optical film without particles in the surface layer. Also described are optical devices using the optical film and methods of making and using the optical films.
摘要:
In a display backlight (120, 220, 420) a specular partial reflector (250, 450) is placed between a circular-mode reflective polarizer (242, 442) and an illumination device (230, 430). The specular partial reflector (450) recycles otherwise unused polarized light (468L) reflected from the circular-mode reflective polarizer (442) which results in an optimized backlight brightness. The main application of the backlight (120) is in liquid crystal displays (100)