First results on a new PIAA coronagraph testbed at NASA Ames
Name
74400J_1.pdf
Description
Proceedings article
Size
2.99 MB
Format
Adobe PDF
Checksum (MD5)
3f54012b913123bf6f4b2fe1b69333f3
Author(s)
Belikov, R.
Pluzhnik, E.
Connelley, M. S.
Witteborn, F. C.
Lynch, D. H.
Cahoy, K. L.
Guyon, O.
Greene, T. P.
McKelvey, M. E.
Date Issued
January 1, 2009
Publisher
SPIE - The International Society for Optical Engineering
Citation
Belikov, R., Pluzhnik, E., Connelley, M., Witteborn, F., Lynch, D., Cahoy, K., & ... McKelvey, M. (2009). First results on a new PIAA coronagraph testbed at NASA Ames. Proceedings Of The SPIE - The International Society For Optical Engineering, 7440(12 pp.). doi:10.1117/12.826772
Abstract
Direct imaging of extrasolar planets, and Earth-like planets in particular, is an exciting but difficult problem requiring a telescope imaging system with 1010 contrast at separations of 100 mas and less. Furthermore, the current NASA science budget may only allow for a small 1-2 m space telescope for this task, which puts strong demands on the performance of the imaging instrument. Fortunately, an efficient coronagraph called the Phase Induced Amplitude Apodization (PIAA) coronagraph has been maturing and may enable Earth-like planet imaging for such small telescopes. In this paper, we report on the latest results from a new testbed at NASA Ames focused on testing the PIAA coronagraph. This laboratory facility was built in 2008 and is designed to be flexible, operated in a highly stabilized air environment, and to complement existing efforts at NASA JPL. For our wavefront control we are focusing on using small Micro-Electro- Mechanical-System deformable mirrors (MEMS DMs), which promises to reduce the size of the beam and overall instrument, a consideration that becomes very important for small telescopes. At time of this writing, we are operating a refractive PIAA system and have achieved contrasts of about 1.2×10-7 in a dark zone from 2.0 to 4.8 λ/D (with 6.6×10-8 in selected regions). In this paper, we present these results, describe our methods, present an analysis of current limiting factors, and solutions to overcome them.
Subjects
Phase Induced Amplitude Apodization
PIAA coronagraph
NASA
Ames coronograph
Earth-like planets
extrasolar planets
telescope imaging system
Micro-Electro-Mechanical-System deformable mirrors
aspheric optics
Fourier Transform
MIT Department
Space Telecommunications Astronomy and Radiation (STAR) Lab
Massachusetts Institute of Technology. Department of Aeronautics and Astronautics
Persistent DSpace Link
