Optical /Technology for Cryo-Vacuum Mirrors

Energen proposes to design and develop a large 30” optical mirror for the AEDC. This cryogenic mirror provides high reflectivity at wavelengths from 2 to 20 microns when operating at temperatures as low as 20 K. A critical design innovation that Energen brings to the project is precision actuation technology that enables in situ mirror adjustments and compensation for the thermal contraction from room temperature to 20 K. The mirror mount enables tip-tilt and piston motion of the optical surface with nanometer resolution. Flexures within the mount system allow for thermal contraction compensation while at the same time eliminating stress concentration through a distributed load carrying mechanism. In Phase I of this effort, the Energen team will develop a detailed engineering model of the mirror and its mount. Analysis will show that the design will maintain mirror figure and enable more advanced performance options for future use at AEDC.