Abstract: The photoacoustic device for measuring the quantity of at least one gas. The Helmholtz-type esonant container comprises at least two tubes closed at their ends and linked together, close to each of their respective ends, by capillary tubes of diameter lower than the diameter of the parallel tubes. Each of the two radiant laser energy sources is physically separated and adapted to supply an excitation energy to the gas in the container at a different emission wavelength. The modulation means modulates the excitation energy supplied by each laser energy source with a modulation frequency corresponding to the acoustic resonance frequency of the container. At least one acoustoelectric transducer disposed on one of the tubes detects the produced acoustic signals produced and supplies an electric signal representative of the gas concentration in the container.

Abstract: According to the invention, in an assembly comprising an electronic component (108), said component is connected by microbeads (107) to at least one heat sink (106, 109), said beads being connected to electrically-conductive lines on said electronic component and to electrically-conductive lines on at least one heat sink, said beads carrying, on the one hand, electrical signals between the electronic component and each heat sink bearing said electrically-conductive lines and, on the other hand, the heat from the electronic component to each heat sink, via heat conduction.

Abstract: A method for making a set of surface-emitting laser diodes comprises the making of reflectors by the epitaxial growth of at least one semiconductor material through a mask having apertures with inclined flanks. This method leads to the obtaining of the Bragg reflectors obtained in situ, removing the need for the ion etching of a semiconductor substrate followed by a phase for the conditioning of the surface of the sample before the preparation of the desired laser structure.Application: optical power source.

Abstract: Disclosed is a method for the making of an optoelectronic device such as buried lasers in which the different layers of the device are chiefly made during a single step of epitaxy by means of a removable mechanical mask.