End retract device for completing spherically shaped reflective film

摘要

Apparatus for shaping the end portions of a reflective film to conform to a spherical shape comprising attaching the end portions of the film to flexible stretch blocks so the film wraps over a surface of the blocks which can be bent to arc positions matching the arc of curvature at the ends of the frame which carries the film in its final spherical configuration, and forcing the stretch blocks to flex about a neutral axis so the surface of the blocks which bend to match the arc of curvature at the ends of the frame move about fixed end points from a chord configuration to an arc configuration matching that of the ends of the frame thereby substantially uniformly stretching the film into its final spherical configuration.