Christian Depeursinge

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The aim of Optical Digital Holography, applied to cells and tissue imaging, is to provide an accurate 3D imaging of biologic materials, down to the microscopic scale. The method has been developed to yield a very precise determination of cells and tissues morphology. Targeted accuracies are in the sub-micron range and allow for the observation of very small movements band deformations, produced, in particular, by depolarization of excitable cells and their metabolic activities. Direct imaging of tissue stru

A technique to perform two-wavelengths digital holographic microscopy (DHM) measurements with a single hologram acquisition is presented. The vertical measurement range without phase ambiguity is extended to the micron-range, thanks to the resulting synthe ...

Background: Digital holography provides a non-invasive measurement of the quantitative phase shifts induced by cells in culture, which can be related to cell volume changes. It has been shown previously that regulation of cell volume, in particular as it r ...

A dual mode microscope is developed to study morphological evolution of mouse myoblast cells under simulated microgravity in real time. Microscope operates in Digital Holographic Microscopy (DHM) and widefield epifluorescence microscopy modes in a time sequential basis. DHM provides information on real time cellular morphology. EGFP transfected actin filaments in mouse myoblast cells function as the reporter for the fluorescence microscopy mode. Experimental setup is fixed in the RPM to observe microgravity

We present a study based on simulations describing how shot noise, an intrinsic part of the recording process with a digital camera, influences the quality of the reconstructed phase images under different beams intensities configurations. ...

This paper presents an optical diffraction tomography technique based on digital holographic microscopy. Quantitative 2-dimensional phase images are acquired for regularly-spaced angular positions of the specimen covering a total angle of π, allowing to bu ...

We have developed a digital holographic microscope (DHM), in a transmission mode, adapted to the quantitative study of cellular dynamics. Living cells are optically probed by measuring the phase shift they produce on the transmitted wave front. The high temporal stability of the phase signal, equivalent to lambda/1800, and the low acquisition time (down to 20 mu s) enables to monitor cellular dynamics processes. An experimental procedure allowing to calculate both the intracellular refractive index and the

We introduce a label-free technology based on digital holographic microscopy (DHM) with applicability for screening by imaging, and we demonstrate its capability for cytotoxicity assessment using mammalian living cells. For this first high content screenin ...

Many biological objects are mainly transparent and weakly scattering, thus a promising (and already widely used) way of imaging them consists in considering optical refractive index variations. The method proposed here permits 3D imaging of the refractive index distribution with a tomographic approach. Usually, the classical Radon transform does not sufficiently take into account the physical interaction between light and biological cells, therefore diffraction has to be considered.

Digital holographic microscopy (DHM) is a technique that allows obtaining, from a single recorded hologram, quantitative phase image of living cell with interferometric accuracy (Marquet et al., 2005). Specifically the optical phase shift induced by the specimen on the transmitted wave front can be regarded as a powerful endogenous contrast agent, depending on both the thickness and the refractive index of the sample. We have recently proposed (Rappaz et al., 2005) a new and efficient decoupling procedure a

Digital holographic microscopy (DHM) is applied to life sciences applications and demonstrate its capability of real-time imaging and quantitative measurements of physiological parameters such as cell volume or mean cell hemoglobin concentration (MCHC) of ...

Digital holographic microscopes using two orthogonal polarized reference waves provides real-time polariscopes. Birefringence induced by internal stress is imaged in optical fibers and in fused silica substrates, where lines are written with low-energy femtosecond pulses.

Based on spectral interferometry and wavelength multiplexing, we demonstrate that a combination of these methods could lead to a 3D imaging system. This system has the advantage of a one-dimensional geometry transmission channel and a limited scanning need. This kind of imaging system could, of course, be of a great interest in small size endoscope with 3D imaging capability and a small channel cross-section (less than 1 mm). Theoretical analysis as well as experimental proof of principle is presented in th

As digital holography achieves numerical reconstruction of the complex wavefront diffracted by specimen, a numerical optics formalism has been developed: numerical filters replace pinholes in Fourier planes, numerical lenses allow aberrations compensation and image magnification.

Quantitative phase recovery of phase objects is achieved by a direct inversion using the defocused weak object transfer function. The presented method is noniterative and is based on partially coherent principles. It also takes into account the optical pro ...

In this Letter we propose a fast off-axis hologram autofocusing (AF) approach that is based on the redundant data elimination by the critical resampling of the contained complex field. Implementation of the proposed methodology enables the real-time AF wit ...

In the past decade, quantitative phase imaging gave a new dimension to optical microscopy, and the recent extension of digital holography techniques to nonlinear microscopy appears very promising, for the phase of nonlinear signal provides additional information, inaccessible to incoherent imaging schemes. Last year, we have reported how the SHG phase makes possible real-time nanometric 3D-tracking of SHG emitters, such as nanoparticles (Shaffer et al., Opt. Express 18, p.17392-17403, 2010). Here, we invest

Digital holographic microscopy (DHM) is a technique that allows obtaining, from a single recorded hologram, quantitative phase image of living cell with interferometric accuracy. Specifically, the optical phase shift induced by the specimen on the transmitted wave front can be regarded as a powerful endogenous contrast agent, depending on both the thickness and the refractive index of the sample. We discuss some approaches allowing to directly obtain separate measurements of the thickness and the refractive

The refractive index and cellular thickness information contained in the phase signal recorded by Digital Holographic Microscopy is measured independently with a dual-wavelength technique exploiting the dispersion of a dye present in the perfusion medium.

We present a theory to extend the classical Abbe resolution limit by introducing a spatially varying phase into the illumination beam of a phase imaging system. It allows measuring lateral and axial distance differences between point sources to a higher ac ...

Christian Depeursinge

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Cells and tissue imaging with digital holographic microscopy

Real-time dual-wavelength digital holographic microscopy with a single hologram acquisition

Early Cell Death Detection with Digital Holographic Microscopy

Dual-mode digital holographic and fluorescence microscopy for the study of morphological changes in cells under simulated microgravity

Shot noise influence in reconstructed phase images SNR in digital holographic microscopy

Living specimen tomography by digital holographic microscopy: morphometry of testate amoeba

Digital holographic microscopy, a new optical imaging technique to investigate cellular dynamics

Label-Free Cytotoxicity Screening Assay by Digital Holographic Microscopy

Diffraction tomography for biological cells imaging using digital holographic microscopy

Erythrocytes analysis with a digital holographic microscope

Digital holographic microscopy applied to life sciences

Real-Time Birefringence Measurement with Digital Holographic Microscopy

Multiplexed 3D imaging using wavelength encoded spectral interferometry: a proof of principle

Numerical Optics in Digital Holography

Quantitative phase restoration by direct inversion using the optical transfer function

Accelerated autofocusing of off-axis holograms using critical sampling

Second harmonic phase microscopy of collagen fibers

Analysis of cellular structure and dynamics with digital holographic microscopy

Simultaneous Cell Morphometry and Refractive Index Measurement with Dual-Wavelength Digital Holographic Microscopy

Beyond the lateral resolution limit by phase imaging