Advanced Mirror Material System

Peregrine will bring together recent laboratory developments and mature the technology so that complete mirror and telescope assemblies can be reliably and robustly produced. This proposed innovation will lower the cost of space mirrors from their current state of the art of $6.4 M/m2 to less than $1.6 M/m2 while maintaining low weight, high stiffness and high performance for x-ray, neutron and UV/optical mirrors. The basis of this approach relies upon Be-38Al (a lower cost beryllium) to create a substrate, the use of coefficient of thermal expansion (CTE) matching phosphorous containing electroless nickel plating (NiP) to establish an amorphous surface, and then single point diamond turning (SPDT) that surface to a precision optical figure out to the edge of the substrate. Be-38Al provides a substrate material that can provide the same stiffness as beryllium because it is not limited by its fracture sensitivity like beryllium. Electroless nickel applied to Be-38Al with the right phosphorous content can match the Be-38Al's CTE, and the use of diamond turning can readily produce optical surfaces that can be used as is or with final polishing.