Patent ID: 7550054

Claim:
A method of manufacturing a mirror for a dish reflector of a system for generating electrical power from solar radiation which includes the steps of: (a) shaping a blank of a deformable material to have a concave surface that is a required surface profile for a mirror; and (b) adhering a back surface of a sheet of reflective glass to the concave surface of the shaped blank to form the mirror; wherein the concave surface is part spherical and step (a) of shaping the blank further includes the steps of: (i) positioning the blank between two halves of a former, each half of the former having a curved former surface that defines part of a cylinder, wherein the act of positioning comprises positioning the blank between the halves so that the former surfaces contact the blank and deforms the blank so that the blank conforms to the curved former surfaces and defines part of a cylinder, the longitudinal axis of the cylinder defining a first axis; (ii) while the blank is positioned between the former halves, cutting the blank along a cylindrical path of movement in the direction of the first axis and separating the blank into a first part and a second part, each part having a cut surface, the longitudinal axis of the cylindrical path of movement defining a second axis, the second axis being perpendicular to the first axis, and (iii) releasing the parts from the former and returning the parts to a state that the blank was in prior to deforming the blank in step (i), with the result that the cut surfaces of the parts define part spherical surfaces, with the first part having a concave surface and the second part having a convex surface.