| 摘要 |
Retroreflective articles provide modulating retroreflection using a front surface that includes at least first and second areas having different transmission characteristics and a back surface that includes retroreflective areas and separation areas. The first and second areas on the front surface are arranged relative to the retroreflective areas and the separation areas on the back surface such that a substantial portion of light incident on the first areas of the front surface at a first angle is transmitted through the first areas of the front surface to the retroreflective areas on the back surface where it is retroreflected back through the front surface. In addition, a substantial portion of light incident on the first areas of the front surface at a second angle is transmitted through the first areas on the front surface to the separation areas. Together, the front and back surfaces manipulate light such that the retroreflective articles provide modulating retroreflection of incident light where the modulation or variation can be between, e.g., retroreflection or no retroreflection, retroreflection of different colors, retroreflection at different brightness levels, etc. In other words, when subjected to incident light from a steady light source, relative movement between the retroreflective article and the light source can result in variations or modulation in the retroreflection of light from the light source. When retroreflective articles provide modulating retroreflection, the variations or changes will tend to increase the conspicuity of an object or person on which the retroreflective article is located. <IMAGE> |
