Abstract
In a previous paper, we described a successful technique, the broadband algorithm, for phasing the primary mirror segments of the Keck telescopes to an accuracy of 30 nm. Here we describe a complementary narrow-band algorithm. Although it has a limited dynamic range, it is much faster than the broadband algorithm and can achieve an unprecedented phasing accuracy of approximately 6 nm. Cross checks between these two independent techniques validate both methods to a high degree of confidence. Both algorithms converge to the edge-minimizing configuration of the segmented primary mirror, which is not the same as the overall wave-front-error-minimizing configuration, but we demonstrate that this distinction disappears as the segment aberrations are reduced to zero.
© 2000 Optical Society of America
Full Article | PDF ArticleMore Like This
Gary Chanan, Mitchell Troy, Frank Dekens, Scott Michaels, Jerry Nelson, Terry Mast, and David Kirkman
Appl. Opt. 37(1) 140-155 (1998)
Achim Schumacher, Nicholas Devaney, and Luzma Montoya
Appl. Opt. 41(7) 1297-1307 (2002)
Fang Shi, Gary Chanan, Catherine Ohara, Mitchell Troy, and David C. Redding
Appl. Opt. 43(23) 4474-4481 (2004)