In the operation of both multiaperture telescopes and segmented mirror telescopes, a primary issue is the phasing of the apertures or mirrors. This is a brief report of the first proof-of- concept experiment of phase diversity using the nonlinear optimization estimation technique for multiaperture systems. A two-telescope system was optically simulated in which piston could be estimated for both a point source and expended objects to .1 (lambda) rms.
Nancy A. Miller,
Alice V. Ling,
"Imaging with phase diversity: experimental results", Proc. SPIE 2029, Digital Image Recovery and Synthesis II, (9 November 1993); doi: 10.1117/12.162001; https://doi.org/10.1117/12.162001