US Patent 7845383 Roman shade with inverted fan shape at its bottom

A window covering in the style of a Roman shade has a straight bottom edge when the shade is lowered and that forms into an inverted fan shape when the shade is raised. Spaced parallel creases in the shade simulate pleats when the shade is in a lowered position and promote accordion-folded pleats when the shade is raised. A pull cord behind the shade lifts the shade from its bottom edge and along its vertical centerline. A two-part bottom rail is secured in the bottom edge of the shade, and each part extends from an outer side edge of the shade to the midportion of the bottom edge, so that when the cord is pulled to raise the shade, the two parts pivot downwardly about the midportion, imparting an inverted fan shape to the bottom edge.