Design and Testing of a One-Meter Membrane Mirror with Active Boundary Control (Conference Proceedings)

摘要

The use of thin film membranes is of considerable interest for lightweight mirror applications. The low areal density makes them ideal for Large aperture imaging applications. One type of setup looked into in the past has been the lenticular design. which consists of a clear Canopy attached to a reflective film that uses positive pressure to set the curvature of the mirror. One drawback to this concept has been the fact that too much error was introduced during the pass through the canopy due to material inhomogeneities and poor optical properties. This is no longer an issue thanks to developments over the past several years in the field of optical quality polymer development. Thin films (less than 24 microns) can now be routinely made with surface roughness. thickness variation. and very good transmission properties well within specification for many visible and IR applications. The next step in this developmental process has been maintaining a prescribed figure in the mirror. This paper summarizes the current efforts in fabricating and testing a 1-meter class lenticular membrane mirror system utilizing active boundary control and stress-coating applications to form a usable aperture for visible imaging applications.