Abstract: An optical device for a biological or chemical sensor includes: an absorption cavity configured to receive a biological or chemical medium; an injection waveguide to inject an analysis light beam into the absorption cavity; and an extraction waveguide to extract a measurement light beam, corresponding to the analysis light beam after transit through the absorption cavity. The absorption cavity has a shape of a right cylinder with an elliptical base. One end of the injection waveguide is placed at a first focus of the ellipse and one and of the extraction waveguide is placed at a second focus of the ellipse. A core of the injection waveguide and a core of the extraction waveguide each have a tip-shaped end, with a constant height in a plane parallel to the generatrix of the right cylinder and a tip-shaped cross section in planes parallel to the base of the right cylinder.

Abstract: A method for regulating the relative position of an analyte of a sample (16) in relation to a light beam (F) includes the illumination of the analyte of the sample (16) with the light beam (F), capturing by an imaging device (38) a transmission image of the beams scattered by the analyte of the sample (16) in order to establish a diffraction pattern, and modifying the relative position of the analyte of the sample (16) in relation to the light beam (F) according to at least one property of the diffraction pattern.

Abstract: A method for observing biological species on a culture medium contained in a container having at least one translucent face, the method including the steps of: a) directing a light beam onto one portion of the translucent face, so as to define at least one illuminated region and at least one non-illuminated region of the face; and b) acquiring an image of a portion of the surface of the culture medium illuminated by the light beam, the acquisition being carried out through at least one of the non-illuminated regions of the translucent face and along an optical acquisition axis forming a non-zero angle (a) with the direction of propagation of the light beam.

Abstract: Porous sol-gel material essentially consisting of units of one or more first polyalkoxysilanes chosen from the following compounds: (chloromethyl)triethoxysilane; 1,3-dimethyltetramethoxydisiloxane; ethyltrimethoxysilane; triethoxy(ethyl)silane; triethoxymethylsilane; triethoxy(vinyl)silane; trimethoxymethylsilane; trimethoxy(vinyl)silane; tetraethoxysilane or tetramethoxysilane (TMOS) and of units of one or more second polyalkoxysilanes chosen from the following compounds: (N-(3-(trimethoxysilyl)propyl)ethylenediamine; 3-aminopropyltriethoxysilane (APTES) and 3-aminopropyltrimethoxysilane, in a first polyalkoxysilane/second polyalkoxysilane molar ratio of 1/0.01 to 1/1, optionally comprising a probe molecule, method of preparation and applications in the trapping of monocyclic aromatic hydrocarbons and other pollutants or in their detection.

Abstract: A method for observing a sample is provided. The method includes the steps of: a) providing a volume (G, V) of a substantially transparent medium having a first refractive index (nint) and having a first surface (S1) that is convex, rounded, or faceted, and a second substantially planar surface (S2), the first surface separating the volume from a surrounding medium (MA) having a second refractive index (nest) that is lower than the first index, the sample to be observed being contained inside the volume or being deposited on the first surface; b) observing the sample through the second substantially planar surface; and c) determining the presence of a substance or an object in the sample by detection during step b), a ring of light that correlates with the volume.

Abstract: The invention relates to a method for observing a sample (12), the sample (12) comprising a set of organisms (14), a solid substrate (16) supporting the set of organisms (14). The method being characterized in that the method includes steps for illuminating at least one portion of the sample (12) with a light beam, for acquiring a first diffraction pattern corresponding to an image of waves from the diffraction of the light beam by at least one portion of the set of organisms (14), for acquiring a second diffraction pattern corresponding to an image of waves from the diffraction of the light beam by at least one portion of the sample (12), for comparing the second diffraction pattern with the first diffraction pattern, for determining at least one characteristic relating to the set of organisms (14) from the result of the comparison step.

Abstract: A method for regulating the relative position of an analyte of a sample (16) in relation to a light beam (F) includes the illumination of the analyte of the sample (16) with the light beam (F), capturing by an imaging device (38) a transmission image of the beams scattered by the analyte of the sample (16) in order to establish a diffraction pattern, and modifying the relative position of the analyte of the sample (16) in relation to the light beam (F) according to at least one property of the diffraction pattern.

Abstract: A method for observing biological species on a culture medium contained in a container having at least one translucent face, the method including the steps of: a) directing a light beam onto one portion of the translucent face, so as to define at least one illuminated region and at least one non-illuminated region of the face; and b) acquiring an image of a portion of the surface of the culture medium illuminated by the light beam, the acquisition being carried out through at least one of the non-illuminated regions of the translucent face and along an optical acquisition axis forming a non-zero angle (a) with the direction of propagation of the light beam.

Abstract: The invention relates to a method for detecting clusters of biological particles (12) on a surface (11), comprising steps that involve: a. determining (E1) a topographical representation (20) of said surface; and b. detecting (E3, E4), on said topographical representation, at least one contour defining a region that is likely to correspond to a cluster of biological particles.

Abstract: The present invention relates to a method for determining the presence or absence of a microorganism, said method including the steps of: 1) providing an enclosure containing a liquid or semi-solid phase consisting of a biological medium capable of containing a living form of said microorganism, nutritional elements, and an enzymatic substrate which is specific to said microorganism and which can be metabolised into at least one VOC metabolite, and a gaseous phase adjacent to said liquid or semi-solid phase; 2) exposing at least said liquid or semi-solid phase to conditions that are propitious for said microorganism to metabolise said enzymatic substrate into a molecule of said VOC metabolite; and 3) determining, by optical transduction, the presence or absence of said VOC metabolite, characterised in that the latter interacts with a nanoporous matrix, said matrix being implemented in a form that is separate from said enzymatic substrate, and in that the detection, by optical transduction, of a change in the

Abstract: A method for observing a sample is provided. The method includes the steps of: a) providing a volume (G, V) of a substantially transparent medium having a first refractive index (nint) and having a first surface (S1) that is convex, rounded, or faceted, and a second substantially planar surface (S2), the first surface separating the volume from a surrounding medium (MA) having a second refractive index (next) that is lower than the first index, the sample to be observed being contained inside the volume or being deposited on the first surface; b) observing the sample through the second substantially planar surface; and c) determining the presence of a substance or an object in the sample by detection during step b), a ring of light that correlates with the volume.

Abstract: The invention relates to a method for detecting clusters of biological particles (12) on a surface (11), comprising steps that involve: a. determining (E1) a topographical representation (20) of said surface; and b. detecting (E3, E4), on said topographical representation, at least one contour defining a region that is likely to correspond to a cluster of biological particles.