Accession Number:

ADP011762

Title:

Coherent and Incoherent Phase Retrieval Using Gaussian Beam Modes

Descriptive Note:

Corporate Author:

CAMBRIDGE UNIV (UNITED KINGDOM) CAVENDISH LAB

Report Date:

2000-09-29

Pagination or Media Count:

4.0

Abstract:

Phase retrieval techniques are important at terahertz frequencies where it is often difficult to determine the phase of a field directly. In this paper we present a phase retrieval technique based on a Gaussian-Beam formalism. We show how the complex mode coefficients of a coherent field can be determined by fitting to intensity distributions at any two planes. We extend the analysis to incoherent or partially-coherent fields by working in terms of coherence matrices rather than mode coefficients. Working with the coherence matrix also allows us to vary the entropy of the field as part of the fitting process and to handle the problem of noise in the measurements more correctly. We illustrate our techniques with some simple examples.

Subject Categories:

  • Optics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE