TPF-C Technology Plan - Exoplanet Exploration Program - NASA

Plan for Technology Development
7.4.3 Technology Demonstration Mirror
Scope
Although the mirror will be completed in March 2007, a critical milestone will be the delivery of
the PSD for the coated TDM in September 2006. Earlier near term milestones are the delivery of
the fused planar blank to ITT, from Corning, in April 2005 and the completion of slumped mirror
in August 2005. From August 2005 to August 2006 the mirror will be fine ground and polished
using small tool lap, full tool active lap, and ion beam figuring. The schedule for the TDM is
given in Table 7-4.
State of the Art TRL 3
The required mid-spatial frequency performance for the TDM has not been demonstrated on the
scale needed for TPF. Smaller mirrors (with a higher areal density) have demonstrated the
required MSF, but in the class of the TDM, the requirement has only been met over part of the
MSF range.
Table 7-4. Technology Demonstration Mirror Schedule
Planned
Completion
Date
Planned Activities Performance Targets TRL
Pre-Phase A
April 2005
Delivery of fused planar blank
from Corning to ITT
CTE uniformity meets or exceeds requirement 3
August 2005 Completion of slumped mirror Mirror is within 0.5mm of net shape and cell structures
are not deformed due to slumping process
4
August 2006
Delivery of PSD for coated
TDM from ITT to JPL
Mirror meets or exceeds spatial surface performance
requirements as described in Table 7
5
Phase A
March 2007 Mirror completed 5
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