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:
An improved optical film having a continuous/disperse phase morphology and a method for making the same is provided. At least one of the continuous and disperse phases comprises a blend of homopolymers which are inter-reacted, as by transesterification. The resulting films exhibit a higher degree of birefringence for a given level of strain than analogous films in which the blend is replaced by a random copolymer.
摘要:
An improved optical film having a continuous/disperse phase morphology and a method for making the same is provided. At least one of the continuous and disperse phases comprises a blend of homopolymers which are inter-reacted, as by transesterification. The resulting films exhibit a higher degree of birefringence for a given level of strain than analogous films in which the blend is replaced by a random copolymer.
摘要:
An improved optical film having a continuous/disperse phase morphology and a method for making the same is provided. At least one of the continuous and disperse phases comprises a blend of homopolymers which are inter-reacted, as by transesterification. The resulting films exhibit a higher degree of birefringence for a given level of strain than analogous films in which the blend is replaced by a random copolymer.
摘要:
A backlight that includes a front reflector and a back reflector that form a hollow light recycling cavity including an output surface is disclosed. The backlight further includes one or more light sources disposed to emit light into the light recycling cavity. The front reflector includes an on-axis average reflectivity of at least 90% for visible light polarized in a first plane, and an on-axis average reflectivity of at least 25% but less than 90% for visible light polarized in a second plane perpendicular to the first plane.
摘要:
A backlight that includes a front reflector and a back reflector that form a hollow light recycling cavity including an output surface is disclosed. The backlight further includes one or more light sources disposed to emit light into the light recycling cavity. The front reflector includes an on-axis average reflectivity of at least 90% for visible light polarized in a first plane, and an on-axis average reflectivity of at least 25% but less than 90% for visible light polarized in a second plane perpendicular to the first plane.
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:
A backlight unit (10) has a hollow cavity (16) instead of employing a light guide. One or more light sources (24a-c), such as LEDs, are arranged to emit light into the cavity, which is formed by a front (12) and a back reflector (14). The backlight is typically of the edge-lit type. The backlight can have a large area, is thin and consists of fewer components than conventional devices. Its design permits light recycling. The unit emits light of a predefined polarisation and can be arranged to have desired horizontal/vertical viewing angle properties. Light is uniformly distributed within the guide and the light output (20b, 2Od) is substantially collimated. Such backlights occupy a specific region in a parameter space defined by two parameters: first, the ratio of the output emission area to the total source emission area should lie in the range 0.0001 to 0.1; and second, the ratio of the SEP to the height of the cavity (H) should be in the range 3 to 10, where the SEP is an average plan view source separation, a special measure of the average spacing of light sources in the plane of the unit. There is also a discussion on the required number of light sources N, their arrangement near the periphery of the cavity, as well as the shape and size of the output emission area. A required minimum brightness uniformity (VESA) value to be maintained, when a subset of Madjacent sources is switched off (where M is at least 0.1 N or M>2 or both), is also disclosed. The backlight can be used for a display or for general lighting purposes.
摘要:
An optical device includes a dichroic polarizer and a multilayer optical film, such as a reflective polarizer or mirror. The multilayer optical film is made using polymers which may allow for the simultaneous orientation of the dichroic and reflective polarizers. The multilayer optical film often contains a set of birefringent first layers and a set of second layers, which may have an isotropic index of refraction. The dichroic polarizers is a polyvinyl alcohol film with a dichroic dye. The multilayer optical film and dichroic polarizer can be stretched at temperatures of 130° C. or less to orient the two films without substantial cracking of the dichroic polarizer. When an optional second polymer is combined with the polyvinyl alcohol, the multilayer optical film and dichroic polarizer can be stretched at temperatures of about 160° C. without substantial cracking of the dichroic polarizer.
摘要:
An optical device includes a dichroic polarizer and a multilayer optical film, such as a reflective polarizer or mirror. The multilayer optical film is made using polymers which may allow for the simultaneous orientation of the dichroic and reflective polarizers. The multilayer optical film often contains a set of birefringent first layers and a set of second layers, which may have an isotropic index of refraction. The dichroic polarizers is a polyvinyl alcohol film with a dichroic dye. The multilayer optical film and dichroic polarizer can be stretched at temperatures of 130.degree. C. or less to orient the two films without substantial cracking of the dichroic polarizer. When an optional second polymer is combined with the polyvinyl alcohol, the multilayer optical film and dichroic polarizer can be stretched at temperatures of about 160.degree. C. without substantial cracking of the dichroic polarizer.