UltraForm Finishing (UFF) is a CNC controlled process designed to remove grinding sub surface damage as well as mid spatial frequency errors for both relatively "soft" glasses as well as "hard" metals and ceramics for many applications. These applications may include the fabrication of forming mandrels used to produce multiple segmented shell mirrors for the International X-Ray Observatory (IXO). The aspheric and freeform optical surfaces required by LISA and WFIRST will benefit from the fabrication advances made with this endeavor. By integrating finite element analysis (FEA) tools with the UFF computer aided manufacturing (CAM) interface, we will be able to optimize the fabrication process and subsequently reduce and/or completely eliminate mid spatial frequency errors. The UFF has the capability to work with a wide range of traditional optical mediums (i.e., combination of belt materials and loose abrasives) in addition to wheels that range from approximately 20 mm up to 150 mm. This makes the UFF suitable for polishing a wide variety of materials for other segmented types of telescope systems such as the Advanced Technology Large Aperture Space Telescope (ATLAST). The wide variety of loose and bound abrasives allows the UltraForm platform to finish hard ceramics, Silicon and SiC. With these hard to process materials,the UFF has shown promise for grinding as well as polishing optical surfaces, on a small scale.
Since 1989 OptiPro has developed and refined conceptual technologies into robust deterministic machines and processes for the optical fabrication industry. Non-NASA commercial applications include the fabrication of flats, spheres, aspheres, and complex conformal shapes such as aerodynamic ogive domes. Commercialization of these technologies has driven very cost effective solutions. The UFF polishing tools' ability to polish a variety of materials from the ground state, removing grinding marks and subsurface damage, makes it especially attractive for applications where mid-spatial-frequency surface errors are an issue such as EUV lithography. Another application is for laser amplifiers, such as the Inertial Confinement Fusion National Ignition Facility (NIF) at Lawrence Livermore National Laboratory and the Laboratory for Laser Energetics, at the University of Rochester. For these types of applications, laser damage threshold and irradiance distribution are critical and therefore mid-spatial frequency errors need to be minimized after the polishing stage.