Practical Aspects of Specification of Extreme Lightweight ZERODUR? Mirrors for Spaceborne Missions

摘要

Extreme Lightweight ZERODUR? Mirrors, analyzed and described in our recent series of papers, have been demonstrated via a representative 1.2m diameter mirror (88% isogrid lightweighted with f0<200Hz). The attributes of such mirrors are suitable for spaceflight in sizes form > 0.5m to < 4m, while the manufacturing approach is compatible with attractive mirror substrate cost and delivery schedules. We will review manufacturing approach together with recent data on the low magnitude and homogeneity of the coefficient of thermal expansion, and on the toughness of the material. Simple ways to specify these mirrors are summarized.