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Simultaneous two-color imaging in digital holographic microscopy.

ABSTRACT: We demonstrate the use of two-color digital holographic microscopy (DHM) for imaging microbiological subjects. The use of two wavelengths significantly reduces artifacts present in the reconstructed data, allowing us to image weakly-scattering objects in close proximity to strongly-scattering objects. We demonstrate this by reconstructing the shape of the flagellum of a unicellular eukaryotic parasite Leishmania mexicana in close proximity to a more strongly-scattering cell body. Our approach also yields a reduction of approximately one third in the axial position uncertainty when tracking the motion of swimming cells at low magnification, which we demonstrate with a sample of Escherichia coli bacteria mixed with polystyrene beads. The two-wavelength system that we describe introduces minimal additional complexity into the optical system, and provides significant benefits.

SUBMITTER: Farthing NE

PROVIDER: S-EPMC6968951 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Simultaneous two-color imaging in digital holographic microscopy.

Farthing Nicola E NE Findlay Rachel C RC Jikeli Jan F JF Walrad Pegine B PB Bees Martin A MA Wilson Laurence G LG

Optics express 20171102 23

We demonstrate the use of two-color digital holographic microscopy (DHM) for imaging microbiological subjects. The use of two wavelengths significantly reduces artifacts present in the reconstructed data, allowing us to image weakly-scattering objects in close proximity to strongly-scattering objects. We demonstrate this by reconstructing the shape of the flagellum of a unicellular eukaryotic parasite <i>Leishmania mexicana</i> in close proximity to a more strongly-scattering cell body. Our appr ...[more]

PMID: 31956278

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