Lightweight Primary Mirror Technology

"Brashear LP proposes to further develop ULE(TM) Lightweight Mirrors. The overallstructural efficiency of primary mirrors, such as the one used in ABL or proposed forSBL, is currently limited by the minimum thickness of the core cell walls, and frontand back face sheets that is achievable with traditional glass manufacturing methods.The technical objectives of this Phase I activity is to establish the lightest weightULE(TM)primary mirror design that is achievable while retaining the performancecharacteristics necessary to satisfy the existing ABL program requirements usingnovel PM mirror manufacturing techniques. Special attention will be given to launchand/or landing requirements of SBL and ABL. This will entail trading front and rearface sheet thickness, core thickness, as well as cell wall thickness, cell size andgeometry. In addition, Brashear LP will evaluate manufacturing techniques that allowan aggressively light-weighted PM to be realized without the complications ofquilting print-thru of the core due to polishing pressures as well as 1-G releasequilting for Space Based systems. Also, core manufacturing techniques will beevaluated which allow thinner face sheets and improve mirror manufacturing timeby altering the current process by which cores and final mirrors are made. The primary initial beneficiary for this SBIR effort is the USAF/BMDOAirborne Laser (ABL) program. The technology and processes developed underthis SBIR wil