Translator Disclaimer
14 September 2005 The Terrestrial Planet Finder Coronagraph dynamics error budget
Author Affiliations +
The Terrestrial Planet Finder Coronagraph (TPF-C) demands extreme wave front control and stability to achieve its goal of detecting earth-like planets around nearby stars. We describe the performance models and error budget used to evaluate image plane contrast and derive engineering requirements for this challenging optical system. We show that when the coronagraph is coupled to an 8th-order band-limited mask, the performance is limited by shearing of the starlight beam across imperfect optics (a.k.a. beam walk), and that this in turn demands tight rigid body pointing, sub-milliarcsecond fine guiding, high-quality optics, and sub-micron positional stability of the optics including the secondary mirror. Additionally we show that the stability of low-order aberrations (focus, astigmatism, coma, and trefoil) is required to be ~ 2-4 Angstroms, while higher-order modes must remain stable to a few picometers.
© (2005) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Stuart B. Shaklan, Luis Marchen, Joseph J. Green, and Oliver P. Lay "The Terrestrial Planet Finder Coronagraph dynamics error budget", Proc. SPIE 5905, Techniques and Instrumentation for Detection of Exoplanets II, 59050D (14 September 2005);

Back to Top