Abstract: A method for characterizing a particle present in a sample, the sample lying between an image sensor and a light source and the sensor lying in a detection plane, includes illuminating the sample with the light source which emits an incident light wave propagating along a propagation axis, and acquiring an image of the sample with the sensor. The sensor is exposed to an exposure light wave. The image includes a plurality of elementary diffraction patterns each corresponding to one particle. The method also includes reconstructing a complex image representative of a complex amplitude of the light wave on a reconstruction surface passing through the sample, based on the acquired image; selecting a region of interest of the complex image corresponding to a particle of interest; forming an extracted image based on the region of interest; and characterizing the particle of interest depending on the extracted region of interest.

Abstract: A method for determining a state of a cell, the cell being placed in a sample, in contact with a culture medium, the method comprising: illuminating the sample with a light source and acquiring an image of the sample with an image sensor, the image sensor lying in a detection plane; from the acquired image, locating a position of the cell in a plane parallel to the detection plane; the method further comprising: from the acquired image, estimating a refractive index of the cell or a relative refractive index of the cell, the relative refractive index corresponding to a refractive index of the cell relative to the refractive index of the culture medium; from the estimation of the refractive index or of the relative refractive index, determining an index of interest of the cell; from the index of interest, classifying a state of the cell among predetermined states, the predetermined states comprising at least one apoptosis state and one living state.

Abstract: A method for characterizing a particle present in a sample, the sample lying between an image sensor and a light source and the sensor lying in a detection plane, includes illuminating the sample with the light source which emits an incident light wave propagating along a propagation axis, and acquiring an image of the sample with the sensor. The sensor is exposed to an exposure light wave. The image includes a plurality of elementary diffraction patterns each corresponding to one particle. The method also includes reconstructing a complex image representative of a complex amplitude of the light wave on a reconstruction surface passing through the sample, based on the acquired image; selecting a region of interest of the complex image corresponding to a particle of interest; forming an extracted image based on the region of interest; and characterizing the particle of interest depending on the extracted region of interest.

Abstract: A method for holographic characterization of a particle contained in a sample, based on an image, or hologram, of the sample obtained by an image sensor when the sample is illuminated by a light source. The hologram is the subject of a holographic reconstruction, to obtain a reference complex image, representative of the light wave transmitted by the sample in a reconstruction plane. A holographic propagation operator is applied to the reference complex image, to obtain a plurality of secondary complex images, from which a profile is determined describing the change in an optical feature of the light wave transmuted by the sample along the axis of propagation of the light wave.

Abstract: A method for identifying a state of a cell contained in a sample, including: illuminating the sample using a light source by producing an incident light wave propagating toward the sample; then acquiring, using a matrix-array photodetector, an image of the sample, the sample being placed between the light source and the matrix-array photodetector such that the matrix-array photodetector is exposed to a light wave resulting from interference between the incident light wave and a diffraction wave produced by each cell; applying a numerical reconstruction algorithm to the image acquired by the matrix-array photodetector, to estimate a characteristic quantity of the light wave reaching the matrix-array detector, at a plurality of distances from the matrix-array photodetector. The value of the characteristic quantity, or its variation as a function of distance, allows the state of the cell to be determined from among predetermined states.

Abstract: A method for identifying a particle contained in a sample, including illuminating the sample using a light source, the light source producing an incident light wave propagating toward the sample, then acquiring, using a matrix-array photodetector, an image of the sample, the sample being placed between the light source and the photodetector such that the matrix-array photodetector is exposed to a light wave that is the result of interference between the incident light wave and a diffraction wave produced by each particle. The method further includes applying a numerical reconstruction algorithm to the image acquired by the photodetector, to estimate a characteristic quantity of the light wave reaching the detector, at a plurality of distances from the detector. The variation in the characteristic quantity as a function of distance allows the particle to be identified.

Abstract: A method for holographic characterization of a particle contained in a sample, based on an image, or hologram, of the sample obtained by an image sensor when the sample is illuminated by a light source. The hologram is the subject of a holographic reconstruction, to obtain a reference complex image, representative of the light wave transmitted by the sample in a reconstruction plane. A holographic propagation operator is applied to the reference complex image, to obtain a plurality of secondary complex images, from which a profile is determined describing the change in an optical feature of the light wave transmuted by the sample along the axis of propagation of the light wave.

Abstract: A method for identifying a state of a cell contained in a sample, including: illuminating the sample using a light source by producing an incident light wave propagating toward the sample; then acquiring, using a matrix-array photodetector, an image of the sample, the sample being placed between the light source and the matrix-array photodetector such that the matrix-array photodetector is exposed to a light wave resulting from interference between the incident light wave and a diffraction wave produced by each cell; applying a numerical reconstruction algorithm to the image acquired by the matrix-array photodetector, to estimate a characteristic quantity of the light wave reaching the matrix-array detector, at a plurality of distances from the matrix-array photodetector. The value of the characteristic quantity, or its variation as a function of distance, allows the state of the cell to be determined from among predetermined states.