Open AccessInterferometric synthetic aperture microscopy for extended focus optical coherence microscopy
Author(s) -
Séverine Coquoz,
Arno Bouwens,
Paul J. Marchand,
Jérôme Extermann,
Theo Lasser
Publication year - 2017
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.25.030807
Subject(s) - optics , interferometry , optical coherence tomography , microscopy , numerical aperture , depth of focus (tectonics) , depth of field , coherence (philosophical gambling strategy) , physics , synthetic aperture radar , point spread function , penetration depth , gaussian beam , focus (optics) , image resolution , resolution (logic) , adaptive optics , computer science , beam (structure) , wavelength , artificial intelligence , paleontology , subduction , quantum mechanics , biology , tectonics
Optical coherence microscopy (OCM) is an interferometric technique providing 3D images of biological samples with micrometric resolution and penetration depth of several hundreds of micrometers. OCM differs from optical coherence tomography (OCT) in that it uses a high numerical aperture (NA) objective to achieve high lateral resolution. However, the high NA also reduces the depth-of-field (DOF), scaling with 1/NA 2 . Interferometric synthetic aperture microscopy (ISAM) is a computed imaging technique providing a solution to this trade-off between resolution and DOF. An alternative hardware method to achieve an extended DOF is to use a non-Gaussian illumination. Extended focus OCM (xfOCM) uses a Bessel beam to obtain a narrow and extended illumination volume. xfOCM detects back-scattered light using a Gaussian mode in order to maintain good sensitivity. However, the Gaussian detection mode limits the DOF. In this work, we present extended ISAM (xISAM), a method combining the benefits of both ISAM and xfOCM. xISAM uses the 3D coherent transfer function (CTF) to generalize the ISAM algorithm to different system configurations. We demonstrate xISAM both on simulated and experimental data, showing that xISAM attains a combination of high transverse resolution and extended DOF which has so far been unobtainable through conventional ISAM or xfOCM individually.