The effects of spatiotemporal coherence on interferometric imaging

TL;DR

This paper systematically investigates how the degrees of spatiotemporal coherence of illumination affect imaging quality, demonstrating methods to control coherence and improve image clarity across various systems.

Contribution

It introduces a systematic approach to analyze and control DSTCI, providing quantitative insights into its effects on image quality and speckle noise reduction.

Findings

Decreased DSTCI reduces speckle noise.

Decomposition of optical fields into wavelets reveals coherence effects.

Method for controlling DSTCI enhances imaging quality.

Abstract

Illumination coherence plays a major role in various imaging systems, from microscopy, metrology, digital holography, optical coherence tomography, to ultrasound imaging. Here, we present a systematic study on the effects of degrees of spatiotemporal coherence of an illumination (DSTCI) on imaging quality. An optical field with arbitrary DSTCI was decomposed into wavelets with constituent spatiotemporal frequencies, and the effects on image quality were quantitatively investigated. The results show the synergistic effects on reduction of speckle noise when DSTCI is decreased. This study presents a method to systematically control DSTCI, and the result provides an essential reference on the effects of DSTCI on imaging quality. We believe that the presented methods and results can be implemented in various imaging systems for characterising and improving imaging quality.