NASA’s Technology Transfer Program solicits inquiries from companies interested in obtaining license rights to commercialize, manufacture and market the following technology. License rights may be issued on an exclusive or nonexclusive basis and may include specific fields of use. NASA provides no funding in conjunction with these potential licenses. THE TECHNOLOGY: NASA Goddard Space Flight Center invites companies to license its innovative process that helps significantly reduce the risk, time, and costs associated with producing lightweight mirrors for demanding instrument applications. The method employs a solid disc of single-crystal silicon (SCS) and calls for most of the polishing to be completed before lightweighting. Due to the extraordinary homogeneity of SCS, the distortion caused by traditional lightweighting processes is significantly reduced. Each mirror is a monolithic structure consisting of a face sheet with a highly polished front optical surface. In Goddard’s process for making these mirrors, the optical surface is formed in a solid SCS blank either by conventional grinding and polishing or by diamond turning. The blank is then lightweighted using Computer Numerical Control (CNC) grinding. For critical applications, post-lightweighting polishing can be performed to further improve the optical surface. Due to the very small amount of material removed during this step, it produces no quilting or print-through of the lightweight support structure. At several points during the process, the mirror is heated to near its melting point to remove small crystalline defects caused by the fabrication process. Each resulting SCS mirror features a homogeneous composition free of internal stress. These parameters inhibit distortion when cooling the mirror to cryogenic temperatures. Under such conditions, the mirrors maintain their optical figure to 1/50th wave root mean square (RMS) or better. At room temperature, SCS has a thermal conductivity about the same as aluminum and a thermal coefficient of expansion about equal to Pyrex glass. So SCS mirrors are extremely resistant to thermal shock and ideal for applications where high heat dissipation is required. Virtually all conventional lightweight mirrors are made by optically grinding and polishing an already lightweighted blank. Mirrors made this way always risk print-through to the optical surface. In some cases this can be removed by a zero-pressure process, such as ion-beam polishing, although these processes tend to be slow and costly. Lightweighting after optical polishing is not an option for conventional materials as their inhomogeneous qualities and internal stresses cause the lightweighting to distort the optical surface. By contrast, in Goddards process for SCS mirrors, optical grinding and polishing is done before lightweighting, eliminating the possibility of print-through. This is due to the extreme homogeneity and absence of stress possible in a monolithic structure from a single crystal. This results in a simple and cost-effective process that is capable of producing mirrors of exceptional quality. To express interest in this opportunity, please submit a license application through NASA’s Automated Technology Licensing Application System (ATLAS) by visiting https://technology.nasa.gov/patent/GSC-TOPS-75 If you have any questions, please contact NASA Goddard Space Flight Center’s Technology Transfer Office at
[email protected] with the title of this Technology Transfer Opportunity as listed in this FBO notice and your preferred contact information. For more information about licensing other NASA-developed technologies, please visit the NASA Technology Transfer Portal at https://technology.nasa.gov/ These responses are provided to members of NASA’s Technology Transfer Program for the purpose of promoting public awareness of NASA-developed technology products, and conducting preliminary market research to determine public interest in and potential for future licensing opportunities. No follow-on procurement is expected to result from responses to this Notice.