Christian Depeursinge

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This paper present a novel approach to perform the tomography of biological specimen based on Digital Holographic Microscopy (DHM). A hologram results from the interference between a reference wave and an object wave reflected from or transmitted through a sample. In the hologram, both amplitude and phase of the field transmitted through the object are registered. In DHM, the object field is recovered when the hologram is processed by a digitally computed replica of the reference wave, allowing quantitative

In this paper we present a method for tomographic imaging using multiple wavelengths in digital holographic microscopy. This method is based on the recording at different wavelengths equally separated in the k-domain, in off- axis geometry of the interference between a reference wave and an object wave reflected by a microscopic sample and magnified by a microscope objective. A couple charged device (CCD) camera records consecutively the resulting holograms, which are then numerically reconstructed to obtai

Digital holographic microscopy (DHM) is a noninvasive optical imaging technique that provides quantitative phase images of living cells. In a recent study, we showed that the quantitative monitoring of the phase signal by DHM was a simple label-free method ...

We present a method for submicrometer tomographic imaging using multiple wavelengths in digital holographic microscopy. This method is based on the recording, at different wavelengths equally separated in the k domain, in off- axis geometry, of the interfe ...

The study of the internal structures of specimens has a great importance in life and materials sciences. The principle of optical diffraction tomography (ODT) consists in recording the complex wave diffracted by an object, while changing the k vector of the illuminating wave. This way, the frequency domain of the specimen is scanned, allowing reconstructing the scattering potential of the sample in the spatial domain. This work presents a method for sub-micron tomographic imaging using multiple wavelengths

Digital holographic microscopy (DHM) is a new optical method taking advantage of coherent properties of light propagation and it provides, without the use of any contrast agent, real-time three-dimensional images of transparent living cells, with an axial ...

Quantitative phase microscopy (QPM) has recently emerged as a powerful label-free technique in the field of living cell imaging allowing to non-invasively measure with a nanometric axial sensitivity cell structure and dynamics. Since the phase retardation ...

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 ...

We present a digital holographic microscope that permits one to image polarization state. This technique results from the coupling of digital holographic microscopy and polarization digital holography. The interference between two orthogonally polarized re ...

Digital holographic microscopy (DHM) is an interferometric technique, providing quantitative mapping of the phase shift induced by semi- transparent microscopic specimens, such as cells, with sub-wavelenght resolution along the optical axis. Thanks to actual PCs and CCDs, DHM provides nowadays cost-effective instruments for real-time measurements at very high acquisition rates, with sub-micron transverse resolution. However, DHM phase images do not reveal the three-dimensional (3D) internal distribution of

Chloride channels represent a group of targets for major clinical indications. However, molecular screening for chloride channel modulators has proven to be difficult and time-consuming as approaches essentially rely on the use of fluorescent dyes or invas ...

We propose and experimentally demonstrate a device in which common-path interferometry combined with off-axis holographic geometry is used to realize a digital holographic camera which can be attached to the camera port of a conventional transmission micro ...

The optical properties within limited volumes of diffusive media can be probed by carrying spatially-resolved measurements of diffused light at short source-detector separation (typically one scattering mean free path). At such distance, analytical models ...

A numerical holographic method, which is able to determine the amplitude components of the Jones vector of a wavefront in addition to its phase and amplitude, is presented. Two reference waves, with orthogonal polarisations interfere with the transmitted or reflected object wave to create the hologram that is recorded on a standard CCD camera. Two wavefronts, one for each perpendicular polarisation state, are numerically reconstructed in intensity. Combining the intensity distribution of these two wavefront

Digital Holographic Microscopy (DHM) is a powerful imaging technique allowing, from a single amplitude image (amplitude and phase), reflected acquisition (hologram), the reconstruction of the entire complex wave front by or transmitted through an object. Because holography is an interferometric technique, the reconstructed phase leads to a sub-wavelength axial accuracy (below lambda/100). Nevertheless, this accuracy is difficult to obtain from a single hologram. Indeed, the reconstruction process consisting

Retrieval of the amplitude and phase of electromagnetic waves made digital holographic microscopy (DHM) capable of revealing morphological details at ultrahigh resolution in the order of a few nanometers only and precisely measuring the refractive index across a sample (e.g. cell or neuron). In short,DHM added a new dimension to optical imaging,whic h explains why it is such an excellent instrument for metrological,but also for biological applications. We believe that DHM is,b y nature,ideally suited for no

In optics, optical elements are used to transform, to filter or to process physical wavefronts in order to magnify images, compensate for aberration or to suppress unwanted diffracted order for example. Because digital holography provides numerical wavefronts, we developed a digital optics, involving numerical elements such as numerical lenses and pinholes, to mimic numerically what is usually done physically, with the advantage to be able to define any shape for these elements and to place them everywhere

In this paper, we present a modified transmission digital holographic microscope that can be used to image the state of polarization. The resulting device, called polarization digital holographic microscope (Pol-DHM), records in off-axis geometry the interference between two orthogonally polarized reference waves and the object wave transmitted by a microscopic sample and magnified by a microscope objective. A CCD camera records the resulting hologram. Using a single hologram, we reconstruct separately the

Spatially-spectrally-resolved reflectance measurements allow in vivo measuring the optical coefficients of absorption and scattering within the cortical tissue. This method, if applied to neural tissue during enhanced activity, could allow a straightforward monitoring of the blood oxygen saturation changes occurring in the brain cortex during hemodynamic responses. Furthermore, it may provide valuable information on possible absorption and scattering changes occurring during stimulation. The feasibility of

Photon migration has been investigated experimentally in vitro on human breast tissues, bovine liver, tissue phantoms, and theoretically by Monte Carlo simulations and diffusion theory. The spatial intensity profiles have been measured at the output surface of a sample illuminated by a collimated beam. Experimental results have then been compared with simulations that assume the sample to be homogeneous. Measurements on phantoms, i.e., fat emulsion and microspheres suspension, and on liver are in good agree

Christian Depeursinge

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Biological cell (pollen grain) refractive index tomography with digital holographic microscopy

Tomography using multiple wavelengths in digital holography: Method, simulations and experiments

Determination of Transmembrane Water Fluxes in Neurons Elicited by Glutamate Ionotropic Receptors and by the Co-transporters KCC2 and NKCC1: A Digital Holographic Microscopy Study

Submicrometer optical tomography by multiple-wavelength digital holographic microscopy

Multi-wavelength digital holographic microscopy for sub-micron topography of reflecting specimens

Cellular Dynamics Revealed by Digital Holographic Microscopy

Quantitative phase-digital holographic microscopy: a new imaging modality to identify original cellular biomarkers of diseases

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

Polarization microscopy by use of digital holography: application to optical- fiber birefringence measurements

Sub-cellular quantitative optical diffraction tomography with digital holographic microscopy

Simultaneous Optical Recording in Multiple Cells by Digital Holographic Microscopy of Chloride Current Associated to Activation of the Ligand-Gated Chloride Channel GABA(A) Receptor

Portable advanced off-axis camera for quantitative phase microscopy

Signification of the phase function parameter gamma explored with a fractal distribution of scatterers

A method for polarisation imaging using digital holography

Automatic procedure for aberrations compensation in digital holographic microscopy

Digital holography for second harmonic microscopy: application to 3D-tracking of nanoparticles

A complete digital optics applied to digital holographic microscopy: Application to chromatic aberration compensation

Birefringence measurement by use of digital holographic microscopy: examples with fiber optics and concrete samples

Determination of local optical properties of the rat barrel cortex during neural activation: Monte-Carlo approach to light propagation

Role of tissue structure in photon migration through breast tissues