摘要:
A light source comprises an electroluminescent panel and a reflective polarizer that is preferably polymeric, birefringent, or both. The reflective polarizer is positioned to receive light generated by the light generating layer. The reflective polarizer transmits light of a first polarization and reflects light of a second polarization back to the light generating layer. The light generating layer diffusely reflects and randomizes the polarization state of the reflected light and recirculates the reflected light back to the reflective polarizer.
摘要:
A display includes a liquid crystal display panel, an optical cavity producing substantially collimated light and a birefringent reflective polarizer.
摘要:
Various combinations of retroreflective sheeting and multilayer polymeric reflective films are disclosed. The reflective film includes alternating layers of at least a first and second polymer, the alternating layers being configured to exhibit a high reflectance for light within a first spectral range and a low reflectance for light within a second spectral range. At least two of the alternating layers can have out-of-plane indices of refraction which differ by no more than 50% of the maximum in-plane refractive index difference. The polymeric layers can define optical repeating units arranged in a sequence to have a specific thickness profile designed to give sharpened spectral transitions. The retroreflective layer preferably exhibits retroreflectance in all planes of incidence, but alternately it can be retroreflective in at least one plane of incidence but not in at least one other plane of incidence.
摘要:
A multilayer film including multiple polymeric layers designed and made to enable the film to reflect light in the near infrared (IR) portion of the visible spectrum. Depending on the amount and range of red light that is reflected, the film of the present invention appears under certain conditions to exhibit a visible color, commonly cyan. The film appears to be substantially clear when viewed against a diffuse white background from approximately a zero degree observation angle, and appears to be cyan when viewed against that background from an observation angle that is greater than a predetermined shift angle.
摘要:
Multilayer optical films having one or more reflection bands are provided. The films include alternating polymeric layers configured to selectively reflect and transmit visible light at a design angle of incidence, where the selective reflection includes first and second visible reflection bands. At least one of the first and second visible reflection bands is a first-order reflection.
摘要:
Multilayer optical films having one or more reflection bands are provided. The films include alternating polymeric layers configured to selectively reflect and transmit visible light at a design angle of incidence, where the selective reflection includes first and second visible reflection bands. At least one of the first and second visible reflection bands is a first-order reflection.
摘要:
Multilayer polymeric films and other optical bodies are provided which is useful in making colored mirrors and polarizers. The films are characterized by a highly uniform change in color as a function of viewing angle.
摘要:
A liquid crystal display (LCD) projection system including a projection panel, a light source, and a reflector. The projection panel includes an LCD and a polarizer on one side of the LCD and a reflective polarizer on the other side. The reflective polarizer is a multilayer stack of pairs of adjacent material layers. Each of the layer pairs exhibits a refractive index difference between the adjacent layers in a first direction in the plane of the reflective polarizer and exhibits essentially no refractive index difference between adjacent layers in a second direction in the plane of the reflective polarizer and orthogonal to the first direction. A quarter-wave plate is secured to the reflective polarizer. Light rays from the light source either pass through the reflective polarizer, and on to the LCD, or are reflected back toward the light source, depending on their polarization. Light which is reflected by the reflective polarizer is reflected by the reflector back toward the LCD again. The use of the quarter-wave plate and the reflector help to recycle what would typically be regarded as wasted light, while at the same time reducing heat build-up within the LCD.
摘要:
An optical film is provided which comprises a disperse phase of polymeric particles disposed within a continuous birefringent matrix. The film is oriented, typically by stretching, in one or more directions. The size and shape of the disperse phase particles, the volume fraction of the disperse phase, the film thickness, and the amount of orientation are chosen to attain a desired degree of diffuse reflection and total transmission of electromagnetic radiation of a desired wavelength in the resulting film.
摘要:
An optical film is provided which comprises a disperse phase of polymeric particles disposed within a continuous birefringent matrix. The film is oriented, typically by stretching, in one or more directions. The size and shape of the disperse phase particles, the volume fraction of the disperse phase, the film thickness, and the amount of orientation are chosen to attain a desired degree of diffuse reflection and total transmission of electromagnetic radiation of a desired wavelength in the resulting film.