Abstract: A concentrator having a reflective surface (1) and a pair of flexible members (2) supporting the deformable reflective surface so as to define its shape. A mechanism (3) is movably mounted to a vertical support and has one end of each of the flexible members (2) attached thereto. A controller drives rotation-changing linkage and tension-varying linkage so as to move the mechanism (3) to impart a toric shaped curvature on the reflective surface (1). This toric shaped curvature minimizes astigmatic aberration due to obliquely incident radiation and changes as the solar point moves throughout the day.

Abstract: As the concentration of electromagnetic radiation, especially solar radiation, can be utilized for constructive purposes it becomes desirable to concentrate the radiation in an economical manner. An essentially fixed concentrating reflector whose shape is generated by gravity's effect on flexible members provides an efficient means to collect and concentrate radiation. Historically in optical science aberrations are to be avoided or eliminated, however this device utilizes the aberration of astigmatism. By taking advantage of the astigmatic foci created by obliquely incident radiation falling upon a substantially sphere-like primary, a comparatively large fixed concentrator can be constructed inexpensively. The resulting tangential and sagittal astigmatic foci are linear. The length of the astigmatic foci can be a substantial portion of the diameter of the concentrator, especially at times of lower solar elevation.