Abstract: Active chemical sensor with optical fiber and its production process.The chemical sensor according to the invention makes it possible to measure a given quantity or magnitude of a fluid. It has a chemical reagent suitable for the measurement and for reacting with the fluid, a support means (20a, 28) for the reagent and a single optical fiber (20) for supplying light to the reagent and recovering the light reflected by the reagent, said sensor being characterized in that the support means incorporates a vinyl imidazole polymer or copolymer film (28) in which the reagent is immobilized, said polymer being in particular directly grafted on to one of the ends (20a) of the optical fiber (20).

Abstract: It is intended for measuring a given characteristic of a fluid medium and comprises at least one assembly having an appropriate reagent for said measurement and serving to interact with the fluid medium, reagent support means, an optical fibre (2) called the emitting fibre and used for transmitting light in the direction of the support means and at least one other optical fibre (4), called the receiving fibre and which recovers at least part of the light from the support means when the latter receive the light from the emitting fibre. The support means comprise a single porous or adsorbant element (10) to which is fixed the reagent and which is positioned facing the emitting fibre and each receiving fibre. This element is in direct contact with the fluid medium when the transducer is immersed in it and therefore has no confinement membrane.

Abstract: It comprises an optical system, two optical fibres on either side of the optical axis of the optical system and longitudinally stagered along said axis and, for each fibre, injecting light into the fibre and detecting the light emerging from the fibre following reflection on an object, the latter being positioned facing the optical system. Electronic processing of the signals supplied by the detector to determine the displacement of the object relative to the optical system and possibly the distance between the object and the optical system.The system has application to the inspection of mechanical parts.

Abstract: Equipment for the emission and distribution of light by optical fibres, particularly for in-line spectrophotometric control with the aid of a double beam spectrophotometer, namely one channel for the reference and one channel for the measurement. It has at least one complementary light source emitting through a system of optical fibres permanently towards a reference cell and sequentially towards one of the n measuring cells corresponding to the controls to be performed, the light information from the reference cell on the one hand and sequentially from each of the n measuring cells on the other being passed by the system of optical fibres respectively to the reference channel and to the measuring channel of the spectrophotometer.

Abstract: The present invention relates to a photometric measuring device making it possible to automatically study complex solutions with variable "background noise."This device comprises a light source (2) making it possible to illuminate a measuring cell, means for splitting the light beam (20, 22) from source (2) into a plurality of individual beams, balancing means (24), means (26) for selecting each wavelength associated with each of the light beams, a discriminator (28) making it possible to distinguish the different wavelengths, means (26) for making the light beams monochromatic, detection means (46) and an analog computing system (44) making it possible to calculate the concentration of several dissolved chemical species.Application to the following or monitoring of chemical reactions.

Abstract: Photometric cell of the type comprising two juxtaposed spherical half-mirrors M.sub.1 and M.sub.2 and a third spherical mirror M facing mirrors M.sub.1 and M.sub.2, the three mirrors having the same radius of curvature, while mirrors M.sub.1 and M.sub.2 have their centers of curvature C.sub.1 and C.sub.2 located on mirror M and slightly displaced with respect to one another and mirror M has its center of curvature C between the two mirrors M.sub.1 and M.sub.2, optical means being provided for introducing a measuring light beam into the cell through an entrance diaphragm E and for extracting it therefrom after multiple reflections on said mirrors through an exit diaphragm S, wherein the mirror M is truncated perpendicular to a line joining the centers C.sub.1 and C.sub.2, the truncated portion of the mirror being replaced by an optical system L operating by transmission, the entrance diaphragm E and exit diaphragm S being positioned level with said optical system L on a line perpendicular to lines C.sub.1 -C.

Abstract: Photometer of the type comprising two facing mirrors, means for introducing a light beam between said mirrors, extraction means for said light beam after multiple reflections on the mirrors and means for introducing a fluid to be measured between these mirrors, wherein the two mirrors are concave mirrors, whose centers of curvature are slightly staggered relative to one another and wherein it comprises a field optics by transmission disposed in the vicinity of the centers and which optically conjugates the mirrors, the light beam introduction means comprising a first optical system having an exit pupil in the vicinity of the field optics, the extraction means of the light beam comprising a second optical system having an entrance pupil in the vicinity of the field optics, said entrance and exit pupils being optically conjugated by the action of the multiple reflections on the mirrors.

Abstract: The device comprises a vertically movable platform for supporting extraction flasks placed above compressed-air impellers. Withdrawal of the top liquid phase from each flask is performed by means of a vertical suction duct, the top end of which has its opening within a non-return chamber at a higher level than the opening of a tube which provides a communication with a pressure-reducing Venturi tube, ejector-nozzle and discharge pipe. The lower end of the suction tube is connected to a plurality of nozzles having their openings at the periphery of each extraction flask and extending in the same horizontal plane which can be set at a predetermined level.

Abstract: The ends of travel of pneumatic jacks are controlled so as to obtain signals which are directly utilizable in fluidics by means of a device comprising a main jack-piston with a hollow operating stem fitted with a plunger and a positionally-adjustable regulating stem, a main cylinder and auxiliary cylinder having control ports for driving fluid and communicating with stationary fluidic control ports, and adjustable fluidic control means actuated in dependence on the position of the regulating stem with respect to a cylindrical slide-valve.