摘要:
A reflective article has a multilayer film covering a patterned retroreflective layer. In one embodiment the patterned retroreflective layer includes a separate indicia layer covering a retroreflective substrate. The indicia are substantially hidden under normal viewing conditions but easily detectable under retroreflective lighting conditions. Various types of retroreflective layers are disclosed. The article can also include microstructured relief patterns which produce holographic images under ambient lighting but which disappear under retroreflective conditions. The multilayer film includes alternating layers of at least a first and second polymer, and has a relatively high reflectivity for normally incident light within a first spectral range which is approximately coextensive with the visible spectrum, and a relatively low reflectance for normally incident light within a second spectral range. The second spectral range can include a transmission window of 15% or less fractional bandwidth located at least partially in the visible spectrum. Film constructions are disclosed which achieve sharper spectral transitions than previously attainable. Film constructions are also disclosed which preserve such sharp transitions even at high entrance (tilt) angles.
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:
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:
Multilayer polymeric films and other optical bodies are provided which is useful in making colored mirrors and polarizers. The films are characterized by a change in color as a function of viewing 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:
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 illumination system including a light source, light guides coupled to the light source, each including an input surface and an output surface, emissive material positioned to receive light from at least one light guide, and a first interference reflector positioned between the emissive material and the output surfaces of the light guides is disclosed. The light source emits light having a first optical characteristic. The emissive material emits light having a second optical characteristic when illuminated with light having the first optical characteristic. The first interference reflector substantially transmits light having the first optical characteristic and substantially reflects light having the second optical characteristic.
摘要:
An illumination system including a light source, a light guide including an output surface, emissive material positioned to receive light from the output surface of the light guide, and an interference reflector positioned such that the emissive material is between the output surface of the light guide and the interference reflector is disclosed. The light source emits light having a first optical characteristic. The emissive material emits light having a second optical characteristic when illuminated with light having the first optical characteristic. The interference reflector substantially transmits light having the second optical characteristic and substantially reflects light having the first optical characteristic.
摘要:
An illumination system including a light source, a light guide including an output surface, a first interference reflector positioned between the light source and the output surface of the light guide, and emissive material positioned between the first interference reflector and the output surface of the light guide is disclosed. The light source emits light having a first optical characteristic. The first interference reflector substantially transmits light having the first optical characteristic and substantially reflects light having a second optical characteristic. The emissive material emits light having the second optical characteristic when illuminated with light having the first optical characteristic.