document title / titre du document TRP W ORK PLAN ... - emits - ESA

TRP Work Plan 2005-2007
Description of Activities
TEC-SB/7935/dc
12/Feb/09
2.2 - Missions in Pre-Assessment Phase: Darwin
TRP Reference:
Title:
MMO-630
High Precision Optical Metrology
The objective of this activity is to improve the reliability of the optical metrology sensors as developed to breadboard level for
precise formation flying of the DARWIN satellites. The aim is to reach the maturity status of "elegant breadboard"
representative in form, fit and function for some presently critical parts (e.g. interferometric head, heterodyne modulation
sub-system and fibre coupling system). An emphasis shall be put on the measurement stability in vacuum and under
reasonable thermal variations as well as vibrational constraints and over representative distances. The activity's detailed
definition shall be made with an aim of using and testing this type of metrology on PROBA-3 and other space missions. The
output of this activity will also help to better define follow on activities currently foreseen in the TRP, addressing miniaturisation
of the current concepts and new measurement techniques.
Deliverables:
Elegant Breadboard
Current TRL: TRL3 Target TRL: TRL4 Application Need/Date: TRL5 by 2008-2009
Application/Mission: Darwin, Proba III Contract Duration: 12 months
SW Clause : - Dossier0 Ref.: T-7971, T-7747
Consistency with Harmonisation
Roadmap and Conclusions:
Roadmap: N/A
TRP Reference: T203-06MM
Title:
Passive optical components for interferometry
The first objective of this activity is to design, manufacture and test passive optical components for interferometry. This
includes the development of achromatic beam splitters, dichroic filters, compensation and polarization plates, wide band
antireflection coatings, etc. The second objective is to establish manufacturing techniques and technologies to achieve a
constantly high optical quality of the above-mentioned components, such that differences between the interferometer arms are
minimized. The functionality and performance of the components shall be demonstrated by means of a breadboard that shall
be subjected to a verification test campaign in an environment compatible with DARWIN mission (e.g. Cryogenic
Interferometry Facility).The broadband infrared beam (6-18 micron) has to be split in a specific ratio and accurately over the
full wavelength range. Current technology for beam-splitters does not allow such accurate beam splitting over wide spectral
ranges. Furthermore a number of dichroic plates, polarization beam splitters, compensator plates, antireflection coatings (e.g.
multilayer dielectric stacks or sub-nm gratings, etc. on bulk and optical waveguides), reflective mirrors (with special metallic
and associated protected coatings) are also used in the interferometer. The selected contractor will investigate and define
techniques to guarantee and control minute differential effects between the arms of the interferometer during the
manufacturing process, and will propose techniques capable of measuring such very small differences (e.g. differential
spectral response, differential polarization effects, differential chromatic dispersion, etc).
Deliverables:
Breadboards of the passive components for interferometry, and modelization software.
Current TRL: TRL2 Target TRL: TRL3-4 Application Need/Date: TRL5 by 2012
Application/Mission: Darwin Contract Duration: 24 months
SW Clause : - Dossier0 Ref.: T-7987
Consistency with Harmonisation
Roadmap and Conclusions:
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