Abstract

The concept of using a phased array of small, inexpensive telescopes to achieve high angular resolution of faint, distant objects is nothing new, but the practical considerations of alignment and cophasing has always limited its implementation. To be effective, the coupling of white light from these telescopes must be done in such a way as to achieve zero optical path difference (OPD) between the object being studied, the telescopes, and the point of beam recombination. In practice, this has always been very difficult due to (1.) static and time varying OPD errors from mechanical sources, (2.) large but predictable OPD shifts due to geometrical aspects of the telescopic array, and, (3.) rapid atmospheric turbulence based OPD modulations. In addition to phase errors, one must also deal with time varying mechanical and turbulence based angular misalignments of the beams.

© 1996 Optical Society of America