Abstract: This invention relates to a device for switching and controlling an electron dose emitted by a micro-emitter comprising a sensor module (30) that receives the output current from the micro-emitter and a voltage to adjust the polarization point of the said device, a comparator module that receives a threshold voltage to adjust the quantity of charges to be emitted, a logical module to initialize the electron emission, and to define whether or not the micro-emitter should emit, a control module that generates the voltages necessary for initialization and extinction of the micro-emitter current pulse, means of varying the threshold voltage.

Abstract: This invention relates to a device for switching and controlling an electron dose emitted by a micro-emitter comprising

Abstract: A miniaturized photoacoustic spectrometer made from a series of stacked substrates. An infrared source is formed in a first substrate. A filter is formed in a second substrate. A micro-trough is machined in a third substrate and a microphone is formed in a fourth substrate. A fifth substrate has a metallic deposit for reflecting light emitted by the infrared source. Resin sealing is provided between the substrates.

Abstract: An electrostatically controlled, tunable Fabry-Perot interferometer is provided with a first, fixed mirror (4) to which a floating electrode (2) is fitted, a second, movable mirror (6) to which first and second control electrodes (8, 10) are fitted, and a resonant cavity of length d, defined by the first and second mirrors. The application of an electrical voltage between the two control electrodes operates to cause displacement of the movable mirror in relation to the fixed mirror, thereby modifying the length of the resonant cavity of the Fabry-Perot interferometer.

Abstract: Process for the production of asymmetrical microporous membranes by double irradiation.A membrane (5) is exposed to two irradiations, whereof one has an inadequate energy level to pass through the same, whereas the other passes through membrane (5).The irradiations produce molecular defects, which are attacked or etched in preferred manner by certain chemical agents. Thus, two networks of pores are obtained, one network being of large diameter and of a non-issuing nature (26), the other being smaller (27, 28, 29) and which issue on to the two surfaces (31, 32) of membrane (5).Application to filtration and sterilization.