A simple desktop optical interferometer is described and demonstrated as a teaching tool for concepts of long-baseline stellar interferometry. The interferometer is compact, portable, and easily aligned. It sits on a base 8" x 10" and uses an aperture mask which is mounted to rotate within a precision ball-bearing. Fringes produced from an artificial star are observed through a microscope by means of a video camera and are displayed on an overhead television monitor. When the aperture mask is rotated rapidly, the rotating fringe patterns seen on the monitor are observed to synthesize sources that are unresolved by individual holes in the mask. Fringes from an artificial double star are used to illustrate the relationship between fringe visibility and source structure and to demonstrate image synthesis.

Date Published: 21 February 2003
PDF: 7 pages
Proc. SPIE 4838, Interferometry for Optical Astronomy II, (21 February 2003); doi: 10.1117/12.457007

Published in SPIE Proceedings Vol. 4838:
Interferometry for Optical Astronomy II
Wesley A. Traub, Editor(s)