Modal foundations of close-packed optical arrays with particular application to infrared and millimeter-wave astronomical interferometry

摘要

A scheme is presented for modeling the behavior of multimode, multielement, close-packed optical systems. The scheme is of particular importance when describing the operation of astronomical interferometers. The basic idea is to find, through singular value decomposition, the fields on the sky and at the detectors, to which the individual telescopes of an array can couple. In the paper, we call these fields eigenfields. Eigenfields are more fundamental than eigenmodes, which are the field distributions that can pass through an optical system unchanged in form, and provide mutually orthogonal basis sets for propagating the second-order statistical properties of a source through the individual telescopes, through the beam combiners, and onto the detectors. Using our scheme it is possible to model many different kinds of interferometer, to include the noise generated by the optical components themselves and to calculate the power coupled into coherent, partially coherent, and incoherent detectors. (C) 2004 American Institute of Physics.