Open AccessHigh-resolution light-scattering imaging with two-dimensional hexagonal illumination patterns: system implementation and image reconstruction formulations
Author(s) -
ChihWei Chen,
Po-Hsun Wang,
Li-Jun Chou,
YinYu Lee,
Bo-Jui Chang,
SuYu Chiang
Publication year - 2017
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.25.021652
Subject(s) - optics , scattering , materials science , microscopy , image resolution , polarization (electrochemistry) , resolution (logic) , light scattering , biological imaging , physics , fluorescence , computer science , chemistry , artificial intelligence
Structured illumination microscopy (SIM) was recently adapted to coherent imaging, named structured oblique-illumination microscopy (SOIM), to improve the contrast and resolution of a light-scattering image. Herein, we present high-resolution laterally isotropic SOIM imaging with 2D hexagonal illuminations. The SOIM is implemented in a SIM fluorescence system based on a spatial-light modulator (SLM). We design an SLM pattern to generate diffraction beams at 0° and ± 60.3° simultaneously to form a 2D hexagonal illumination, and undertake calculations to obtain optimal SLM shifts at 19 phases to yield a reconstructed image correctly. Beams of linear and circular polarizations are used to show the effect of polarization on the resolution improvement. We derive the distributions of the electric field of the resultant hexagonal patterns and work out the formulations of the corresponding coherent-scattering imaging for image reconstruction. The reconstructed images of gold nanoparticles (100 nm) confirm the two-fold improvement of resolution and reveal the effect of polarization on resolving adjacent nanoparticles. To demonstrate biological applications, we present the cellular structures of a label-free fixed HeLa cell with improved contrast and resolution. This work enables one to perform high-resolution dual-mode - fluorescence and light-scattering - imaging in a system, and is expected to broaden the applications of SOIM.