abstract |
A sheeting includes a layer of a shape-memory polymer material having a surface of microlenses, wherein each of the microlenses is associated with one of a plurality of images within the sheeting. The layer of the shape-memory polymer material is responsive to an external stimulus; e.g., temperature, solvent, or moisture; by transitioning from a first state in which an optical property of the microlenses has a first value to a second state in which the optical property of the microlenses has a second value. The microlenses have refractive surfaces that transmit light to positions within the sheeting to produce a composite image from the images formed within the sheeting when the layer of the shape-memory polymer material is in one of the first state and the second state. At least one of the images is a partially complete image, and each of the images is associated with a different one of the microlenses. |