Effect of wavefront error on 10(-7) contrast measurements.
Received October 11, 2005; accepted November 10, 2005; posted December 2, 2005 (Doc. ID 65234) We have measured a contrast of 6.5 x 10(-8) from 10 to 25 lambda/D in visible light on the Extreme Adaptive Optics testbed, using a shaped pupil for diffraction suppression. The testbed was designed with a minimal number of high-quality optics to ensure low wavefront error and uses a phase-shifting diffraction interferometer for metrology. This level of contrast is within the regime needed for imaging young Jupiter-like planets, a primary application of high-contrast imaging. We have concluded that wavefront error, not pupil quality, is the limiting error source for improved contrast in our system.
Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550, USA. evans74@llnl.gov
Julia W
JW
Evans
Gary
G
Sommargren
Bruce A
BA
Macintosh
Scott
S
Severson
Daren
D
Dillon