UltraForm Finishing (UFF) and UltraSmooth Finishing (USF) are CNC processes 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) and (NXGO). The aspheric and freeform optical surfaces required by LISA and WFIRST will also benefit from the fabrication advances made with this endeavor. By integrating finite element analysis (FEA) tools with the UFF and USF computer aided manufacturing (CAM) interface, we will be able to optimize the fabrication process and subsequently reduce and/or completely eliminate mid spatial frequency and slope 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 a variety of sizes of wheels. The USF with its variety of pads, pad shapes and durometer is capable of smoothing 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 abrasive slurries make the UFF and USF ideal for finishing hard ceramics, Silicon and SiC. The UFF has shown promise for grinding as well as polishing these hard ceramic surfaces.
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 developed into very cost effective solutions. The combination of UFF and USF polishing tools can be used to polish a variety of materials, removing grinding marks and subsurface damage. This makes these processes excellent candidates for applications where mid-spatial-frequency and slope 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. These processes are also being utilized for many new military optical systems requiring conformal shaped optics in the very hard optical ceramics and the softer optical glasses. Producers of stainless steel injection mold inserts for military optical visors have also adapted UFF technologies.
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