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Active hexagonally segmented mirror to investigate new optical phasing technologies for segmented telescopes.
Frédéric Gonté1, Christophe Dupuy, Bruno Luong
1European Southern Observatory, Karl-Schwarzschild-Strasse 2, 85748 Garching, Germany. fgonte@eso.org
Applied Optics
|November 12, 2009
Summary
A new test bench precisely aligns hexagonal segments for the European Extremely Large Telescope
Area of Science:
- Optical engineering
- Astronomy instrumentation
Background:
- The European Extremely Large Telescope's primary mirror requires precise alignment of 984 hexagonal segments.
- Nanometer-level precision in piston, tip, and tilt is essential for optical phasing sensors.
Purpose of the Study:
- To study four optical phasing sensor technologies.
- To present the design and integration of a test bench for sensor evaluation.
Main Methods:
- Development of a test bench featuring an active segmented mirror with 61 hexagonal segments.
- Each segment controlled in piston, tip, and tilt by piezoactuators with sub-nanometer precision.
Main Results:
- Demonstration of closed-loop control achieving high precision.
- Validation of the test bench for studying optical phasing sensor technologies.
Conclusions:
- The developed test bench is suitable for evaluating optical phasing sensor technologies.
- The system demonstrates the capability for nanometer-level alignment crucial for future telescopes.
