Christian Depeursinge

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In this paper we present a new method to achieve quantitative phase contrast imaging in Digital Holographic Microscopy (DHM) that allows to compensate for phase aberrations and image distortion by recording of a single reference hologram.We demonstrate tha ...

We present here a three-dimensional evaluation of the amplitude point-spread function (APSF) of a microscope objective (MO), based on a single holographic acquisition of its pupil wavefront. The aberration function is extracted from this pupil measurements ...

A novel approach for the simulation of the field back-scattered from a rough surface is presented. It takes into account polarization and multiple scattering events on the surface, as well as diffraction effects. The validity and usefulness of this simulat ...

We present a method and apparatus for local and superficial measurement of the optical properties of turbid media. The depth probed is on the order of 1 transport mean free path of the photon. The absorption coefficient, reduced scattering coefficient and ...

Red blood cell (RBC) parameters such as morphology, volume, refractive index, and hemoglobin content are of great importance for diagnostic purposes. Existing approaches require complicated calibration procedures and robust cell perturbation. As a result, ...

Optical second harmonic generation, thanks to its coherent nature, is a suitable signal for interferometric measurements, such as digital holography: a well-established imaging technique that allows recovering of the complex diffraction wavefields from which it is possible to extract both amplitude- contrast and quantitative phase images. We believe that application of digital holography to non-linear optical fields might ultimately be the key to phase- related functional imaging. In a first approach, we re

We present a method to image Jones vector by use of digital holography. We demonstrate that with a single hologram acquisition, the method allows to image and to calculate Jones vector and derive the polarization parameters. The principle consists in using two reference waves polarized orthogonally that interfere with an object wave and to reconstruct separately the two wave fronts. Simulated and experimental data are compared to a theoretical model in order to evaluate the precision limit of the method for

The disclosed invention describes a new apparatus performing a new data acquisition for quantitative refractive index tomography. It is based on a linear scanning of the specimen, opposed to the classical approaches based on rotations of either the sample ...

In this work, we demonstrate single-shot, simultaneous recording and subsequent retrieval of one incoherent and two holographic (intensity and phase) images from the same camera frame. Demultiplexing of incoherent and holographic signals in the spatial fre ...

In this article we present a method to achieve tri-dimensional contouring of macroscopic objects. A modified reference wave speckle interferometer is used in conjunction with a source of reduced coherence. The depth signal is given by the envelope of the i ...

A simple model is proposed in order to evaluate the complex amplitude point spread function (intensity and phase) of a microscope objective. The model is based on the Fresnel diffraction theory and takes also into account the possible optical aberrations. Experimental evaluation of this amplitude point spread function has been carried out by using a holographic set-up and 66 nanometers gold spheres as punctual objects. The measured values are then compared with the theoretical predicted model.

We propose to use digital holographic microscopy (DHM) with an illumination in the near infrared spectrum bandwidth, where the silicon is known to have small absorption. With such an illumination condition, it is possible to observe a wider range of specimens than in the visible spectrum, providing a new metrology technique for 3D silicon micro-systems characterization. Suitability of DHM with near infrared illumination for micro-optical elements and wafer inspection is demonstrated. The intrinsic robustnes

Digital holograms are recorded by a CCD camera and are numerically reconstructed, in intensity and phase, by means of an algorithm which calculates their discrete Fresnel transform. By using a low-coherence source, the tomography of a 3D scene can be performed without lateral scanning with a depth resolution equal to the coherence length and a lateral resolution equal to the diffraction limit of the microscope objective used

In this review, we summarize how the new concept of digital optics applied to the field of holographic microscopy has allowed the development of a reliable and flexible digital holographic quantitative phase microscopy (DH-QPM) technique at the nanoscale p ...

The present invention discloses a method and its associated apparatus to retrieve the amplitude and, especially, the phase of nonlinear electromagnetic waves. The application field of the present invention is optical imaging. A sample is probed by coherent ...

We present a method to image Jones vector by use of digital holography. We show that with unique hologram acquisition, our method permits to image and to calculate Jones vector and therefore polarization parameters. The idea is to use two reference waves polarized perpendicularly that interfere with object wave and to reconstruct separately the two wave fronts. The precision and limitations of the method are evaluated here using a numerical model.

Few models, based on the diffraction theory, are proposed in order to evaluate the point spread function of different microscope objectives used in a digital holographic microscope. Because in holography the phase information is essential, a 3D amplitude point spread function (APSF), modulus and phase, is necessary, in order to properly deconvolute the 3D images obtained. Scalar Debye theory, paraxial approximation and vectorial Debye theory are used to solve the diffraction problem and the theoretical pred

In this paper, Digital Holographic Microscopy (DHM) is presented as a powerful tool for quality control of micro-optical components. It will be shown that not only the single-shot full field-of-view nanometer axial resolution makes DHM an ideal solution for such samples, but the DHM numerical wavefront correction formalism is perfectly adapted to provide advanced features like aberration coefficients, radius of curvature or optical surfaces roughness measurements. Both transmission and reflection configurat

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 have recently proposed a new and efficient decoupling procedure allowing to directly obtain separate measureme

Digital Holographic Microscopy (DHM) has been used to investigate the spontaneous cell membrane fluctuations (CMF) of the Red Blood Cell. DHM as an interferometric technique is able to accurately provide the wavefront deformation induced by a transparent specimen, including living cells in a transmission configuration. From a numerical reconstruction of a single hologram, quantitative phase contrast images are obtained. The local phase shift is proportional to the specimen thickness with accuracy of 5-10 nm

Christian Depeursinge

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Total aberrations compensation in digital holographic microscopy with a reference conjugated hologram

Amplitude point spread function measurement of high NA microscope objectives by digital holographic microscopy

Monte Carlo simulation of the field back-scattered from rough surfaces

Method for measuring locally and superficially the scattering and absorption properties of turbid media

Comparative study of human erythrocytes by digital holographic microscopy, confocal microscopy, and impedance volume analyzer

Digital holographic microscopy at fundamental and second harmonic wavelengths

Jones vector imaging by use of digital holography: simulation and experimentation

Apparatus and method for quantitative phase tomography through linear scanning with coherent and non-coherent detection

Single-shot, simultaneous incoherent and holographic microscopy

Off-axis low coherence interferometry contouring

Point spread function model for microscopic image deconvolution in digital holographic microscopy

Digital holographic microscopy for silicon microsystems metrology

Optical tomography by means of a numerical low-coherence holographic technique

Exploring Neural Cell Dynamics with Digital Holographic Microscopy

Method and apparatus for retrieval of amplitude and phase of nonlinear electromagnetic waves

Jones vector imaging by use of digital holography: Simulation results

Point spread function models for digital holographic microscopy

Digital holographic microscopy for nanometric quality control of micro- optical components

Erythrocytes volume and refractive index measurement with a digital holographic microscope

Exploring red blood cell membrane dynamics with digital holographic microscopy