Abstract: A novel rubber band powered balloon is presented. No spine, frame, or other support member is used to resist the tension of the rubber band. Instead, the balloon, formed from a substantially non-elastomeric material, is sufficiently rigid when inflated such that supports for the rubber band can be directly connected to the balloon's outer skin. In addition, one embodiment of the present invention includes a novel flapping-vane propulsion system in which the rotational motion of the rubber band is converted into reciprocating motion of the vane.

Abstract: The present invention provides a projector having particular application for use in front projection composite photographic systems. In particular, the present invention relates to composite color photography, whether still, motion picture, or video in which foreground and background scenes are separately recorded and subsequently combined, using known "blue screen" or special background color techniques, to form a single image. The present invention includes a high pressure, short arc, mercury-xenon lamp in an optical system to produce a high intensity beam at wavelengths of either: 436 n.m. (blue); 545 n.m. (green); 589 n.m. (yellow) or 650+ n.m. (red). The selected color beam is then manipulated by optical elements into close correspondence to the viewing angle of a camera lens, and made coincident with the camera view by means of a beam splitter. Unwanted light is removed from the system through a "light trap" which traps and systematically absorbs incident light.

Abstract: An improved projection screen is provided having particular application for use in front projection composite photography. A substrate screen backing is provided onto which a plurality of tiles of screen material is attached. Each of the tiles of screen material is formed in the shape of a regular, concave hexagon whose connective line segment edges describe a concave arc from a first segment point "A" to a midpoint "M", wherein the concave arc has a radius of curvature R equal to the distance between segment point A and the midpoint M. A convex arc is described having a radius R from the midpoint M to a second segment point "B". Each of the tiles of screen material are attached to the substrate backing in a regular periodic fashion, such that the backing is tessellated with tiles of screen material. In the present embodiment, the edges of each tile of screen material are overlapped with adjacent tiles of material, in order to form a homogenous projection screen.