Laser light-field fusion for wide-field lensfree on-chip phase contrast nanoscopy

TL;DR

This paper presents a novel laser light-field fusion technique for wide-field lensfree on-chip phase contrast nanoscopy, achieving high-resolution, marker-free imaging of nanoscale particles over large areas without complex sample prep.

Contribution

It introduces laser light-field fusion for lensfree nanoscopy, enabling high-quality phase contrast imaging with resolution beyond the diffraction limit and pixel pitch, without synthetic aperture methods.

Findings

Successfully detected 300 nm particles over 30 mm² field-of-view

Achieved resolving power more than five times below pixel pitch

Surpassed diffraction limit by over 40%

Abstract

Wide-field lensfree on-chip microscopy, which leverages holography principles to capture interferometric light-field encodings without lenses, is an emerging imaging modality with widespread interest given the large field-of-view compared to lens-based techniques. In this study, we introduce the idea of laser light-field fusion for lensfree on-chip phase contrast nanoscopy, where interferometric laser light-field encodings acquired using an on-chip setup with laser pulsations at different wavelengths are fused to produce marker-free phase contrast images of superior quality with resolving power more than five times below the pixel pitch of the sensor array and more than 40% beyond the diffraction limit. As a proof of concept, we demonstrate, for the first time, a wide-field lensfree on-chip instrument successfully detecting 300 nm particles, resulting in a numerical aperture of 1.1, across a large field-of-view of $\sim$ 30 mm$^2$ without any specialized or intricate sample preparation, or the use of synthetic aperture- or shift-based techniques.