Four-dimensional image formation theory of optical coherence tomography

TL;DR

This paper develops a comprehensive 4D imaging theory for optical coherence tomography that accurately predicts resolution and imaging features, especially in high-NA systems, by incorporating a four-dimensional pupil function and Fourier transforms.

Contribution

It introduces a novel 4D frequency space framework for OCT imaging, enabling precise modeling without approximations and providing new insights into high-NA optical systems.

Findings

Accurate calculation of optical resolution in OCT.

Insight into image formation with high-NA systems.

Framework for handling aberrations and dispersion simultaneously.

Abstract

We construct an accurate imaging theory for optical coherence tomography/microscopy (OCT/OCM) without approximations to calculate precise optical resolution and imaging characteristics. Our theory represents a broadband light source using a four-dimensional (4D) pupil function with a dimension for light frequency (reciprocal of wavelength) as the fourth axis in 4D frequency space. Consequently, 4D space-time representation is required in real space, connected to the 4D frequency space by a 4D Fourier transform. Our theory provides insight into a peculiar image formation in OCT/OCM, particularly when an apparatus has a high numerical aperture (NA) optical system to handle aberrations and dispersions simultaneously.