Abstract: A method for observation of a sample, the sample comprising microorganisms immersed in a nontransparent culture medium, the culture medium being favorable to the development of the microorganisms, the sample being arranged between a light source and an image sensor, the method comprising: a) illuminating the sample with the light source, the light source emitting light propagating along an axis of propagation; b) acquiring an image of the sample by the image sensor; c) from the image acquired, characterization of the microorganisms; the method being characterized in that: the culture medium extends, parallel to the axis of propagation, to a thickness of less than 500 ?m.

Abstract: There is provided a device allowing a sample to be observed in a first mode, by lensless imaging using a first sensor. The first mode allows a first image to be obtained, on the basis of which a region of interest of the sample may be identified. The device then allows, via a relative movement, the region of interest to be analyzed using a more precise second mode and in particular using an optical system coupled to a second sensor.

Abstract: A method for observing a sample (10), the sample lying in a plane of the sample defining radial coordinates, the method comprising the following steps: a) illuminating the sample using a light source (11), able to emit an incident light wave (12) that propagates toward the sample along a propagation axis (Z); b) acquiring, using an image sensor (16), an image (I0) of the sample (10), said image being formed in a detection plane (P0), the sample being placed between the light source (11) and the image sensor (16), such that the incident light wave sees an optical path difference, parallel to the propagation axis (Z), by passing through the sample; c) processing the image acquired by the image sensor; wherein the processing of the acquired image comprises taking into account vectors of parameters, respectively defined at a plurality of radial coordinates, in the plane of the sample, each vector of parameters being associated with one radial coordinate, and comprising a term representative of an optical para

Abstract: A method for determining a parameter of a particle present in a sample, the method comprising the following steps: a) illuminating the sample with the light source, the light source emitting an incident light wave that propagates along a propagation axis; b) acquiring an image of the sample with the image sensor, the image sensor being exposed to an exposure light wave; c) determining a position of the particle in the detection plane; d) on the basis of the acquired image, applying a propagation operator, for a plurality of distances from a detection plane, so as to estimate, at each distance, a complex amplitude of the exposure light wave; e) on the basis of the complex amplitude estimated, at various distances, obtaining a profile representing a variation of the complex amplitude of the exposure light wave along an axis parallel to the propagation axis and passing through the position of the particle.

Abstract: A method for observing a sample includes illuminating the sample with a light source and forming a plurality of images, by an imager, the images representing the light transmitted by the sample in different spectral bands. From each image, a complex amplitude representative of the light wave transmitted by the sample is determined in a determined spectral band. The method further includes backpropagation of each complex amplitude in a plane passing through the sample, determining a weighting function from the back-propagated complex amplitudes, propagating the weighting function in a plane along which the matrix photodetector extends, updating each complex amplitude, in the plane of the sample, according to the weighting function propagated.

Abstract: There is provided a device allowing a sample to be observed in a first mode, by lensless imaging using a first sensor. The first mode allows a first image to be obtained, on the basis of which a region of interest of the sample may be identified. The device then allows, via a relative movement, the region of interest to be analyzed using a more precise second mode and in particular using an optical system coupled to a second sensor.

Abstract: The invention relates to a method for observing a fluorescent sample lying in a sample plane, where the sample comprises a fluorescent agent able to emit a fluorescence light wave in a fluorescence spectral band when it is illuminated by an excitation light wave, in an excitation spectral band. The method includes illuminating the sample using a first light source, in a first illumination spectral band in the excitation spectral band, and acquiring a first image of the sample, in the fluorescence spectral band, using an image sensor; and illuminating the sample using a second light source, in a second spectral band, outside of the fluorescence spectral band, and acquiring a second image of the sample, in the second spectral band, using the image sensor.

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 of discriminating a living cell from a dead cell, and a device for implementing the method, the method including: using a lens-free imaging device to acquire a diffraction figure corresponding to a cell; and determining a light intensity on a central area of an elementary diffraction figure associated with the cell. It can thus be determined if the studied cell is a living cell or a dead cell.

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: The invention relates to a method for observing a fluorescent sample (10), lying in a plane (P10), called the sample plane, the sample comprising a fluorescent agent (10f) able to emit a fluorescence light wave (?f), in a fluorescence spectral band (??f), when it is illuminated by an excitation light wave (?e), in an excitation spectral band (??e), the method comprising the following steps: a) illuminating the sample (10) using a first light source (11), in a first illumination spectral band (??1), in the excitation spectral band (??e0, and acquiring a first image (I1) of the sample, in the fluorescence spectral band, using an image sensor (30); b) illuminating the sample (10) using a second light source (12), in a second spectral band (??2), outside of the fluorescence spectral band, and acquiring a second image (I2) of the sample, in the second apectral band, using the image sensor; the image sensor (30) being coupled to an optical system (20) such that: in the fluorescence spectral band (??f), the obj

Abstract: In accordance with embodiments herein, microfluidics systems and methods are described for identifying and/or tracking particles in a droplet. For example, the particle may be a bead, a cell, or any other type of particle. For example, embodiments herein are useful in distinguishing cells from other particles. The microfluidics systems and methods provide the capability to image a large area (e.g., a few square millimeters) within a digital fluidics chamber using interference microscopy, wherein the image of the interference pattern is acquired, instead of an image of the micrometric object itself. The interference pattern results from the incoming light that interferes with the light scattered by the object. In the case of micrometric objects (e.g., cells, bacteria, etc.), the acquired interference pattern may typically be about 100 jum in diameter so that the area can be imaged using a lens-free imaging configuration or using a low magnification lens.

Abstract: The invention relates to a method for observing a sample, in particular an anatomopathological slide formed from a thin thickness of a sampled biological tissue. It includes a step of illuminating the sample with a light source and acquiring, with an image sensor, an image representing the light transmitted by the sample. The image undergoes holographic reconstruction, so as to obtain a representation, in the plane of the sample, of the light wave transmitted by the latter. The method includes applying an impregnating fluid to the sample, such that the sample is impregnated with said impregnating liquid, said impregnating liquid having a refractive index strictly higher than 1.

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: The invention relates to a method for observing a sample (15), comprising the illumination of the sample using a light source (11) and the acquisition of an image (Io) of the sample using an image sensor (16), the sample being disposed between the image sensor and the light source. Iterative steps are applied to the acquired image (Io), also referred to as a hologram, comprising: a single iterative numerical propagation (h), such as to estimate a complex image (A) of the sample in a reconstruction plane (P10) or in a detection plane (P0), in which the image sensor extends. The complex image can be used for the characterisation of the sample.

Abstract: The invention relates to a method for observing a sample, in particular an anatomopathological slide formed from a thin thickness of a sampled biological tissue. It includes a step of illuminating the sample with a light source and acquiring, with an image sensor, an image representing the light transmitted by the sample. The image undergoes holographic reconstruction, so as to obtain a representation, in the plane of the sample, of the light wave transmitted by the latter. The method includes applying an impregnating fluid to the sample, such that the sample is impregnated with said impregnating liquid, said impregnating liquid having a refractive index strictly higher than 1.

Abstract: This method for characterizing a state of adhesion of the particles is applied via a system including a source of spatially coherent light and a photodetector array, the particles being contained in a liquid medium, the liquid medium being delimited by a transparent surface, the particles being able to adhere to the transparent surface. The method includes: illuminating the medium with the source of spatially coherent light; acquiring at least one image by the photodetector array, the image being formed by radiation transmitted by the illuminated medium and including at least one elementary diffraction pattern, each elementary diffraction pattern corresponding to waves diffracted by a particle during the illumination of the medium; and computing, from at least one acquired image and for at least one particle, a primary indicator characterizing the state of adhesion of the particle to the transparent surface.

Abstract: The method is provided for characterizing agglomeration of particles in a liquid containing an analyte, including introducing liquid into a fluid chamber; mixing the liquid with a bifunctional reagent, lighting the fluid chamber using an excitation light beam extending through the fluid chamber in a longitudinal direction (X); acquiring at least one image using a matrix photodetector, each image including pixels (In(x,y), x,y representing the coordinates of a pixel of an image, the image (I(x,y)) being formed by radiation transmitted by the lighted fluid chamber; and calculating from at least one acquired image (I(x,y)), at least one indicator (Ind2) characterizing the particle agglomeration. The photodetector can be positioned less than 1 cm from the fluid chamber, and during the calculation step, the calculated indicator (Ind2) is representative of the intensity of the pixels of the image. The method advantageously allows for characterizing the agglomeration of particles in a liquid.

Abstract: The invention relates to a method for observing a sample, in particular an anatomopathological slide formed from a thin thickness of a sampled biological tissue. It includes a step of illuminating the sample with a light source and acquiring, with an image sensor, an image representing the light transmitted by the sample. The image undergoes holographic reconstruction, so as to obtain a representation, in the plane of the sample, of the light wave transmitted by the latter. The method includes applying an impregnating fluid to the sample, such that the sample is impregnated with said impregnating liquid, said impregnating liquid having a refractive index strictly higher than 1.

Abstract: A method and a device for determining a concentration of lipids in a microorganism such as a micro-alga by illuminating a sample containing microorganisms and acquiring a total diffraction pattern of the sample is acquired, the total diffraction pattern including a plurality of unit diffraction pattern each associated with a microorganism.