Purely numerical compensation for microscope objective phase curvature in digital holographic microscopy: Inuence of digital phase mask position.

Ecole Polytechnique Fédérale de Lausanne (EPFL), Institut d'Optique Appliquée, Ch-1015 Lausanne, Switzerland.
Journal of the Optical Society of America A (Impact Factor: 1.56). 12/2006; 23(11):2944-53. DOI: 10.1364/JOSAA.23.002944
Source: PubMed


Introducing a microscope objective in an interferometric setup induces a phase curvature on the resulting wavefront. In digital holography, the compensation of this curvature is often done by introducing an identical curvature in the reference arm and the hologram is then processed using a plane wave in the reconstruction. This physical compensation can be avoided, and several numerical methods exist to retrieve phase contrast images in which the microscope curvature is compensated. Usually, a digital array of complex numbers is introduced in the reconstruction process to perform this curvature correction. Different corrections are discussed in terms of their influence on the reconstructed image size and location in space. The results are presented according to two different expressions of the Fresnel transform, the single Fourier transform and convolution approaches, used to propagate the reconstructed wavefront from the hologram plane to the final image plane.

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Available from: Frédéric Montfort, Oct 07, 2015
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    Optics and Lasers in Engineering 05/2015; 68. DOI:10.1016/j.optlaseng.2014.12.011 · 2.24 Impact Factor
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    • "This means that provided that the optical elements in the image half space remain unchanged , this calibration will therefore remain valid even if the object half space is modified (object and object location, direction and curvature of the illumination beam). The reconstruction methods mentioned above [11] [12] [13] [14] [15] made reconstruction in the image half space. This means that the image of the object in plane O is reconstructed by propagating the hologram over a distance d from C to O. "
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    Applied Optics 05/2015; 54(15):4672. DOI:10.1364/AO.54.004672 · 1.78 Impact Factor
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    • "To reconstruct the object image, we use an algorithm based on the diffraction scalar theory, Fresnel approximation [19] [20] [21] [22]. We follow the standard procedure [23] with steps which include: Fourier transform to separate the twin images, Fresnel transform to reconstruct the object image from the +1 order, correction for tilt and spherical aberrations, numerical focalization. "
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