Patent ID: 8414824

Claim:
A method of constructing a thin film mirror, comprising: (a) attaching a thick film to a suction chamber having edges which lie in a surface having the required geometry for the thin film mirror to be constructed where the thin film attaches to the edges; (b) applying a partial vacuum to the suction chamber such that tension is introduced into the thin film; (c) adjusting the partial vacuum in the suction chamber to form the thin film surface of the desired mirror geometry; wherein the mirror zone having the desired geometry is expanded by preliminary deforming the thin film before attaching to the suction chamber by: attaching the thin film to two circular disks in a closed pressure chamber, the disks having a common axis and edges of the desired surface geometry of the mirror to be constructed with the side edges of the thin film joined together to shape the thin film into a circular cone; and deforming the film by adjusting the tensioning with a forcing pump and by additional tensioning the thin film by using a mechanism for moving the disks apart along the common axis to a desired distance.