Abstract: A device and a method for observing an object by imaging, or by lensless imaging. The object is retained by a holder defining an object plane inserted between a light source and an image sensor, with no enlargement optics being placed between the object and the image sensor. An optical system is arranged between the light source and the holder and is configured to form a convergent incident wave from a light wave emitted by the light source, and for forming a secondary light source, conjugated with the light source, positioned in a half-space defined by the object plane and including the image sensor, such that the secondary source is closer to the image sensor than to the holder. This results in an image with a transversal enlargement factor having an absolute value of less than 1.

Abstract: A device including a light source, an image sensor, and a holder defining two positions between the light source and the image sensor. Each position is able to receive an object with a view to its observation. An optical system is placed between the two positions. Thus, when an object is placed in a first position, it may be observed, through the optical system, via a conventional microscopy modality. When an object is placed in the second position, it may be observed via a second lensless imagery modality.

Abstract: A device including a light source, an image sensor, and a holder defining two positions between the light source and the image sensor. Each position is able to receive an object with a view to its observation. An optical system is placed between the two positions. Thus, when an object is placed in a first position, it may be observed, through the optical system, via a conventional microscopy modality. When an object is placed in the second position, it may be observed via a second lensless imagery modality.

Abstract: A system for analyzing a transparent particle including: an analysis pathway, including a first light source emitting an analysis light beam, and a first optical system focusing the analysis light beam in a focusing plane; and a position control pathway including a second light source, an image sensor, and a second optical system at least partially merged with the first optical system. The image sensor is offset relative to the image of the focusing plane by the second optical system. The system makes it possible to control correct positioning of the particle, even though it is transparent, and without disturbing the analysis pathway.

Abstract: The invention concerns a method for identifying biological particles from a stack of holographic images obtained by means of an optical system. A stack of image blocks centered on the biological particle to be analysed is extracted from the stack of images and a reference block corresponding to the focus plan is determined. A characteristic magnitude is calculated for each block of the stack and the profile of this characteristic magnitude along the optical axis of the system is compared with a plurality of standard profiles relative to known types of particle. Alternatively, blocks of the stack are extracted from the stack of blocks for predetermined defocusing deviations and the extracted blocks are compared with standard blocks relative to known types of particle.

Abstract: A device and a method for observing an object by imaging, or by lensless imaging. The object is retained by a holder defining an object plane inserted between a light source and an image sensor, with no enlargement optics being placed between the object and the image sensor. An optical system is arranged between the light source and the holder and is configured to form a convergent incident wave from a light wave emitted by the light source, and for forming a secondary light source, conjugated with the light source, positioned in a half-space defined by the object plane and including the image sensor, such that the secondary source is closer to the image sensor than to the holder. This results in an image with a transversal enlargement factor having an absolute value of less than 1.

Abstract: A method of analyzing a sample receiving a particle of interest, including: defining a reference point located on a first interface of the sample, or at a known distance from the sample, along the optical axis of the optical system; acquiring a reference image transmission of the sample, the object plane of the optical system being located at a known distance from the reference point along an axis parallel to the optical axis of the optical system, and the particle of interest being located outside of the object plane; using the reference image, digitally constructing a series of reconstructed images, each associated with a predetermined offset of the object plane along the optical axis of the optical system; and using the series of reconstructed images, determining the distance along an axis parallel to the optical axis of the optical system, between the particle of interest and the reference point.

Abstract: Determining an optical property of a sample having an illumination of a surface of the sample with the aid of a light beam, so as to form, on the surface of the said sample, an elementary illumination zone, corresponding to the part of the said surface illuminated by the said sample. A detection of N optical signals, backscattered by the sample, each optical signal emanating from the surface of the sample at a distance, termed the backscattering distance, from the said elementary illumination zone, N being an integer greater than or equal to 1, so as to form as many detected signals. A determination of at least one optical property of the sample, by comparison between: a function of each signal thus detected and a plurality of estimations of the said function each estimation being carried out by considering a predetermined value of the said optical property, characterized in that during the said detection step, at least one backscattering distance is less than 200 pm.

Abstract: A system for analyzing a transparent particle including: an analysis pathway, including a first light source emitting an analysis light beam, and a first optical system focusing the analysis light beam in a focusing plane; and a position control pathway including a second light source, an image sensor, and a second optical system at least partially merged with the first optical system. The image sensor is offset relative to the image of the focusing plane by the second optical system. The system makes it possible to control correct positioning of the particle, even though it is transparent, and without disturbing the analysis pathway.

Abstract: A method of analyzing a sample receiving a particle of interest, including: defining a reference point located on a first interface of the sample, or at a known distance from the sample, along the optical axis of the optical system; acquiring a reference image transmission of the sample, the object plane of the optical system being located at a known distance from the reference point along an axis parallel to the optical axis of the optical system, and the particle of interest being located outside of the object plane; using the reference image, digitally constructing a series of reconstructed images, each associated with a predetermined offset of the object plane along the optical axis of the optical system; and using the series of reconstructed images, determining the distance along an axis parallel to the optical axis of the optical system, between the particle of interest and the reference point.

Abstract: The invention concerns a method for identifying biological particles from a stack of holographic images obtained by means of an optical system. A stack of image blocks centred on the biological particle to be analysed is extracted from the stack of images and a reference block corresponding to the focus plan is determined. A characteristic magnitude is calculated for each block of the stack and the profile of this characteristic magnitude along the optical axis of the system is compared with a plurality of standard profiles relative to known types of particle. Alternatively, blocks of the stack are extracted from the stack of blocks for predetermined defocusing deviations and the extracted blocks are compared with standard blocks relative to known types of particle.

Abstract: The invention relates to a method for correcting an optical signal produced by a sample comprising the following steps: illuminating a surface of the sample by a first light beam, produced by a first light source, the said first light source being coupled to a first optical system, focusing the said first light beam in an object focal plane of the first optical system, the said object focal plane being situated, in the sample, at a measuring depth z from the surface of the sample; measuring, with a first photodetector, of a first optical signal backscattered by the sample in response to the first light beam, the first photodetector producing a first measured signal representative of the said first optical signal, a spatial filter being interposed between the first optical system and the first photodetector, the spatial filter comprising a window which transmits the said first optical signal towards the said first photodetector, the window being disposed in a conjugate focal plane of the object focal plane

Abstract: The invention relates to a method for correcting an optical signal produced by a sample comprising the following steps: illuminating a surface of the sample by a first light beam, produced by a first light source, the said first light source being coupled to a first optical system, focusing the said first light beam in an object focal plane of the first optical system, the said object focal plane being situated, in the sample, at a measuring depth z from the surface of the sample; measuring, with a first photodetector, of a first optical signal backscattered by the sample in response to the first light beam, the first photodetector producing a first measured signal representative of the said first optical signal, a spatial filter being interposed between the first optical system and the first photodetector, the spatial filter comprising a window which transmits the said first optical signal towards the said first photodetector, the window being disposed in a conjugate focal plane of the object focal plane

Abstract: The invention relates to a method for determining an optical property of a sample, comprising the following steps: illumination of a surface of the sample with the aid of a light beam, so as to form, on the surface of the said sample, an elementary illumination zone, corresponding to the part of the said surface illuminated by the said sample; detection of N optical signals, backscattered by the sample, each optical signal emanating from the surface of the sample at a distance, termed the backscattering distance, from the said elementary illumination zone, N being an integer greater than or equal to 1, so as to form as many detected signals; determination of at least one optical property of the sample, by comparison between: a function of each signal thus detected; and a plurality of estimations of the said function each estimation being carried out by considering a predetermined value of the said optical property, the method being characterized in that during the said detection step, at least one b

Abstract: Provided is a system for detecting analytes of interest present in a gas sample, including a layer of porous material, positioned at the surface of a substrate so as to extend longitudinally along a fluidic flow path of the gas sample, said porous material containing a plurality of probe molecules, each probe molecule being able to react with the analyte of interest by causing a change in the spectral properties of said probe molecule. Also included is a a pump for generating a flow of the gas sample along the fluidic path so that the gas sample comes into contact with said layer of porous material. The system also includes at least one optical detection device capable of successively detecting, at distinct detection areas of said porous material layer distributed along said fluidic path, a change in the spectral properties of at least one of said probe molecules.

Abstract: A device for lighting an object, with light source provided with a member for sampling a portion of the light, application to the measurement of flux variations of the source. The device includes at least one light source emitting an illuminating light around an illumination axis, for lighting the object, and a photodetector.

Abstract: A device for optical measurement of materials includes a zone opposite a dot including a material, a light source emitting light along an axis in the direction of the zone, where the material interacts with the light it receives, and a light guide to convey a proportion of the light emitted by the dot under the effect of the illumination. The guide includes a light scatterer associated with the source and causing a proportion of the light emitted by the dot to penetrate into the guide, such that it is guided in a direction perpendicular to the axis; the scatterer is annular in shape, and thus delimits a zone of the light guide, and the area of the zone is greater than or equal to the area of the cross-section of the portion of light beam incident to the material.

Abstract: A device for optical measurement of materials includes a zone opposite a dot including a material, a light source emitting light along an axis in the direction of the zone, where the material interacts with the light it receives, and a light guide to convey a proportion of the light emitted by the dot under the effect of the illumination. The guide includes a light scatterer associated with the source and causing a proportion of the light emitted by the dot to penetrate into the guide, such that it is guided in a direction perpendicular to the axis; the scatterer is annular in shape, and thus delimits a zone of the light guide, and the area of the zone is greater than or equal to the area of the cross-section of the portion of light beam incident to the material.

Abstract: A device for lighting an object, with light source provided with a member for sampling a portion of the light, application to the measurement of flux variations of the source. The device includes at least one light source emitting an illuminating light around an illumination axis, for lighting the object, and a photodetector.

Abstract: The invention relates to a system (1) for detecting analytes of interest present in a gas sample. The detection system comprises a layer (30) of porous material positioned along the fluidic flow path for the gas, the material containing probe molecules capable of reacting with the analyte of interest. The detection system also comprises an optical device (50) capable of successively detecting a change in the spectral properties of the probe molecules at different detection areas (32) of the porous material layer (30).