An
astronomical interferometer is an of telescopes or mirror segments acting together to probe structures with higher resolution by means of
interferometry. The benefit of the interferometer is that the
angular resolution of the instrument is nearly that of a telescope with the same
aperture as a single large instrument encompassing all of the individual photon-collecting sub-components. The main drawback is that it does not collect as many photons as a large instrument of that size. Thus it is mainly useful for fine resolution of the more luminous astronomical objects, such as close
binary stars. Another drawback is that the maximum angular size of a detectable emission source is limited by the minimum gap between detectors in the array.