Ultra-broadband Optical Diffraction Tomography

TL;DR

This paper introduces ultrabroadband optical diffraction tomography (ODT), achieving over 150 nm spectral bandwidth and 150 nm resolution, enabling detailed 3D imaging and spectral analysis of biological samples.

Contribution

The study presents the first ultrabroadband ODT technique covering over 150 nm spectral bandwidth, allowing for broadband refractive index measurement and spectral identification in 3D samples.

Findings

Achieved over 150 nm spectral bandwidth in ODT.

Enabled spectral and material-dependent nanoparticle identification.

Demonstrated 3D imaging of HeLa cells with spectral resolution.

Abstract

Optical diffraction tomography (ODT) is a powerful non-invasive 3D imaging technique, but its combination with broadband light sources is difficult. In this study, we introduce ultrabroadband ODT, covering over 150 nm of visible spectral bandwidth with a lateral spatial resolution of 150 nm. Our work addresses a critical experimental gap by enabling the measurement of broadband refractive index changes in 3D samples, a crucial information that is difficult to assess with existing methodologies. We present broadband, spectrally resolved ODT images of HeLa cells, obtained via pulse-shaping based Fourier transform spectroscopy. The spectral observations enabled by ultrabroadband ODT, combined with material-dependent refractive index responses, allow for precise three-dimensional identification of the nanoparticles within cellular structures. Our work represents a crucial step towards time and spectrally-resolved tomography of complex 3D structures with implications for life and materials science applications.