Abstract: A method for measuring the heights of patterns of an object, including: a light emission, the light includes a propagation mode of interest for at least one wavelength of interest, an illumination of the surface of the object by the light, a reflection of the light by the surface of the object, a collection of the reflected light, a division of the wavefront of the reflected light into division components, by at least one pattern of the illuminated surface, a filtering of the collected light, including a modal filtering removing all modes other than the propagation mode of interest, for the wavelengths of interest, and from the filtered light, and for the wavelengths of interest, an extraction of information about phase differences between the division components.

Abstract: A proximity detector employs a capacitive sensor, having: at least one detection antenna including numerous capacitive proximity sensors which each include a measuring electrode, the antenna being positioned close to an object or body; electronic elements for exciting the electrodes and processing the distance measurement signals originating from the capacitive sensors; and digital elements of controlling the electronic elements and of calculating the distances between the electrodes and the body or object using the processed measurement signals. The detection antenna also contains a single guard for all of the measuring electrodes. Moreover, the electronic elements have, for each detection antenna, a floating or floating excitation capacitive bridge which co-operates with polling elements in order sequentially to measure the respective capacitances between each electrode and the object or body to be measured.

Abstract: Method for biomass determination in a medium, in particular a medium containing biological cells suspended in a conductive fluid, the biomass concentration (X) being obtained from a difference between a first capacitance signal (C?1) of the medium, measured at a first frequency, and a second capacitance signal (C?2) of the medium, measured at a second frequency. The method includes a separate correction of each of the measured signals, based at least on one correction level, the first correction level including a correction of the signals measured in accordance with a model dependent on the conductance of the medium at the first and second frequencies. The invention is useful in biomass measurement systems.

Abstract: A proximity detector employs a capacitive sensor, having: at least one detection antenna including numerous capacitive proximity sensors which each include a measuring electrode, the antenna being positioned close to an object or body; electronic elements for exciting the electrodes and processing the distance measurement signals originating from the capacitive sensors; and digital elements of controlling the electronic elements and of calculating the distances between the electrodes and the body or object using the processed measurement signals. The detection antenna also contains a single guard for all of the measuring electrodes. Moreover, the electronic elements have, for each detection antenna, a floating or floating excitation capacitive bridge which co-operates with polling elements in order sequentially to measure the respective capacitances between each electrode and the object or body to be measured.

Abstract: A device for determining the characteristics of a biomass, includes: a probe (S,S′) including electrodes, two or four in number, for injecting a current into a medium containing biological cells and for reading the voltage applied to the medium, and a resistance for measuring the injected current; a conditioning unit (10) including an alternating voltage generator (112) and a circuit (200) processing current and voltage measuring signals, so as to deliver signals (C,G) respectively of measurement of the capacity and conductance of the medium. The conditioning unit (10) includes a zero method measuring bridge (150) automatically controlled to deliver the signals (C,G) of measurement of the medium capacity and conductance. The invention is useful for characterizing media containing biological cells, in particular for controlling biological fermentation process.

Abstract: A method for measuring axial deviation in a taut-wire alignment system (1) that includes a dynamically grounded resistive wire (2) extending along a longitudinal reference axis and adjacent to elements to be aligned (3). The method comprises applying an AC voltage signal to a measurement electrode provided with a reference electrode, the measurement electrode being arranged in a measurement plane in a holder attached to an element to be aligned (3); carrying out a measurement using a capacitive bridge that includes a first capacitor consisting of the measurement electrode and the wire, as well as a second capacitor, in order to provide a measurement signal representing an axial position of the measurement electrode relative to the taut wire (2) ; and processing the measurement signal to provide data indicating the axial deviation between the element to be aligned (3, 7) and a predetermined alignment position. The method is particularly suitable for aligning elements in linear colliders.

Abstract: A positioning actuator with three axes includes a base having a movable supporting member and a device for moving the member up and down, and a shaft connecting the movable head of the actuator to the base. The connecting shaft forms a swivel-type double linkage enabling sideways movement of the head relative to the base, and the lower end of the connecting shaft engages a part made of elastomeric material and is provided within the movable supporting member.