US Patent 7382500 Variable reflectance cover

A variable reflectance cover for a scanning system. The cover comprises a backing moveable through a plurality of positions. Moving the backing through the plurality of positions varies the reflectance of the cover. In one embodiment, the backing is an endless rotatable belt. In a second embodiment, the backing is a removable panel having a first side with a first reflectance and a second side with a second reflectance. In yet a third embodiment, the backing includes polarizers placed adjacent to a reflective panel. Rotating one polarizer relative to another varies the reflectance of the cover.