Generalized Gouy phase for focused partially coherent light and its implications for interferometry

Generalized Gouy phase for focused partially coherent light and its implications for interferometry

Pang, X.
Fischer, D.G.
Visser, T.D.

Electrical Engineering, Mathematics and Computer Science

Telecommunications

2012-05-23

The Gouy phase, sometimes called the phase anomaly, is the remarkable effect that in the region of focus a converging wave field undergoes a rapid phase change by an amount of ?, compared to the phase of a plane wave of the same frequency. This phenomenon plays a crucial role in any application where fields are focused, such as optical coherence tomography, mode selection in laser resonators, and interference microscopy. However, when the field is spatially partially coherent, as is often the case, its phase is a random quantity. When such a field is focused, the Gouy phase is therefore undefined. The correlation properties of partially coherent fields are described by their so-called spectral degree of coherence. We demonstrate that this coherence function does exhibit a generalized Gouy phase. Its precise behavior in the focal region depends on the transverse coherence length. We show that this effect influences the fringe spacing in interference experiments in a nontrivial manner.

http://resolver.tudelft.nl/uuid:3b472779-6c01-45a4-963b-830c20eac13c

https://doi.org/10.1364/JOSAA.29.000989

Optical Society of America

1084-7529

http://www.opticsinfobase.org/josaa/abstract.cfm?URI=josaa-29-6-989

Journal of the Optical Society of America A, 29 (6), 2012

Institutional Repository

journal article

© 2012 Optical Society of America