1. An article, comprising: a first means for mounting said article comprising at least a top rail, a second means for operating said article, comprising one or more pull cords, and a third, tight-controlling means for modifying the passage of light through a base area by its covering and uncovering of said base area, said top rail being fixedly and removably connected to a stable surface, and said top rail being hingedly connected to at least one edge of said tight-controlling means, said pull cords passing slidably through one or more apertures in or near said light-controlling means, each said aperture substantially fixed in position relative to a point on said light-controlling means, said pull cords passing slidably through one or more apertures substantially fixed in position relative to said stable surface, each said pull cord comprising at least a filament, an anchored end of each said filament being fixedly attached to an anchor point, each said anchor point either being substantially fixed in position relative to a predetermined point on a said panel, or being hingedly connected at a fixed distance from a predetermined point on said light-controlling means, a free end of said pull cords being located substantially near an opposite end of said filaments to said anchored end of said filaments, said light-controlling means comprising a plurality of panels and one or more origami folds, said panels being hingedly interconnected by said origami folds, said origami folds being either linear or nonlinear, said light-controlling means and said origami folds thereon having a position, a scale, and an orientation predetermined and resolved with respect to said first and second means whereby said base area is substantially covered and uncovered by the operation of said light-controlling means, each point on said origami folds having a pivot axis around which two adjacent said panels may rotate, any two said pivot axes having an angle between them, at least one said angle being substantially between zero and 180 degrees, said rotation about said pivot axes occurring substantially interdependently by a transmission of forces from one said pivot axis to its adjacent said pivot axes due to said angle(s), or by a transmission of bending forces in said panels to rotational forces about their adjacent pivot axes due to said nonlinear origami folds, wherein the variation of a pulling force on said free end of said pull cords causes said rotation of said panels about said origami folds, thereby expanding or collapsing said light-controlling means, thereby revealing or concealing said base area.