Abstract: A solar energy concentrator comprising a cylindrical Fresnel lens, a specially shaped and positioned reflecting mirror, and a shaped tubular receptor for conveying the collected energy to terminals is described. These concentrators are arrayed parallel and contiguous to each other and oriented generally along an East-West line to receive the sun's radiant energy, and the lenses together with the special reflectors and designed to accomodate large elevation angle variations of the sun. The large acceptance angles achieved with the image collapsing concentrator, while at the same time maintaining a high concentration ratio, improves the reception of diffused as well as direct sunlight and the small surface area of receiving tubes diminishes the thermal radiation losses. A method for determining the shape and location of the special image collapsing reflector is described and applied to solar concentrators employing both lenses and reflectors of cylindrical and three dimensional forms.

Abstract: A light reflective signaling and warning device shaped and arranged relative to an encompassing reference sphere so that light directed toward the signaling and warning device from any area on the reference sphere is reflected toward the same area, self-articulated to intensify light reflection therefrom, color coded to indicate the disposition of the signaling and warning device relative to a source of light, and restorably deformable under the temporary application of excessive force thereto, widely useful in diverse different applications.