Wide-field Intensity Fluctuation Imaging

Qingwei Fang; Alankrit Tomar; Andrew K Dunn

doi:10.1101/2023.07.29.551117

Wide-field Intensity Fluctuation Imaging

bioRxiv [Preprint]. 2023 Jul 29:2023.07.29.551117. doi: 10.1101/2023.07.29.551117.

Authors

Qingwei Fang¹, Alankrit Tomar², Andrew K Dunn^{1

2}

Affiliations

¹ Department of Biomedical Engineering, The University of Texas at Austin, Austin, 78712, TX, US.
² Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, 78712, TX, US.

Abstract

The temporal intensity fluctuations contain important information about the light source and light-medium interaction and are typically characterized by the intensity autocorrelation function, $g_{2} (τ)$ . The measurement of $g_{2} (τ)$ is a central topic in many optical sensing applications, ranging from stellar intensity interferometer in astrophysics, to fluorescence correlation spectroscopy in biomedical sciences and blood flow measurement with dynamic light scattering. Currently, $g_{2} (τ)$ at a single point is readily accessible through high-frequency sampling of the intensity signal. However, two-dimensional wide-field measurement of $g_{2} (τ)$ is still limited by camera frame rates. We propose and demonstrate a 2-pulse within-exposure modulation approach to break through the camera frame rate limit and obtain the quasi $g_{2} (τ)$ map in wide field with cameras of only ordinary frame rates.

Keywords: autocorrelation function; camera; intensity fluctuation; within-exposure modulation.

Publication types

Preprint

Abstract

Publication types

Grants and funding