Open AccessMetal clad waveguide (MCWG) based imaging using a high numerical aperture microscope objective
Author(s) -
Thomas Söllradl,
Frederic A. Banville,
Vincent Chabot,
Michael Canva,
Michel Grandbois,
Paul G. Charette
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.25.001666
Subject(s) - optics , surface plasmon resonance , numerical aperture , materials science , image resolution , microscope , surface plasmon , depth of field , biological imaging , resolution (logic) , microscopy , plasmon , nanotechnology , physics , wavelength , computer science , nanoparticle , artificial intelligence , fluorescence
Evanescent-field based methods such as surface plasmon resonance (SPR) have been used very effectively for label-free imaging of microscopic biological material in close proximity to a sensing surface. However, the shallow probing depth of SPR (typically less than ~200 nm) can be problematic when imaging relatively thick biological objects such as cells or bacteria. In this paper, we demonstrate how metal-clad waveguides (MCWG) can be used to achieve deeper probing depth compared to SPR while maintaining good imaging spatial resolution. Comparative numerical simulations of imaging spatial resolution versus probing depth are shown for a number of common SPR, long-range SPR, and MCWG configurations, demonstrating that MCWG offer the best compromise between resolution and depth for imaging thick biological objects. Experimental results of synthetic target and live cell imaging are shown that validate the numerical simulations and demonstrate the capabilities of the method.