This paper discusses the operation and imaging properties of various types of optical heterodyne interferometer. Conditions needed to achieve confocality in differential interference microscopes are considered. This leads to a novel extended focus phase imaging mode. Results are presented which demonstrate this mode of operation and show the ability of the technique to produce accurate phase measurement on samples with warp and tilt, over a range much greater than the depth of focus of the objective lens.

Date Published: 1 February 1994
PDF: 11 pages
Proc. SPIE 2083, Microscopy, Holography, and Interferometry in Biomedicine, (1 February 1994); doi: 10.1117/12.167432

Published in SPIE Proceedings Vol. 2083:
Microscopy, Holography, and Interferometry in Biomedicine
Adolf Friedrich Fercher; Aaron Lewis; Halina Podbielska M.D.; Herbert Schneckenburger; Tony Wilson, Editor(s)