Abstract: A continually supported assembly capable of being space launched includes a base and a thin optical substrate having a light collecting first surface and an opposite rear surface. An elastically coupling medium couples the rear surface of optical substrate and said base to one another. At least one force-coupled actuator is interspersed within said elastic coupling medium for controllably altering the shape of said optical substrate.

Abstract: A front to back coefficient of thermal expansion difference between surfaces of a mirror segment is reduced by coating a selected surface. The other surface may be also coated in order to obtain an overall bulk coefficient of thermal expansion for the mirror segment. A plurality of mirror segments having coefficients of thermal expansion matched by coatings are selected for assembly thereby avoiding the need to physically change the positions of the various segments in order to bring them into correct relationship or to refocus the image using other optics.