Abstract:
Le dispositif de mesure photo-acoustique de la quantit d'au moins un gaz comporte : - une cuve rsonnante (14, 114, 214, 314A, 314B) de type Helmholtz constitue dau moins deux tubes ferms leurs extrmits et relis entre eux, proximit de chacune de leurs extrmits, par des tubes capillaires de diamtre infrieur au diamtre des tubes parallles et - un moyen (15, 55) dintroduction de gaz dans ladite cuve. Ce dispositif comporte, en outre : - au moins deux sources d'nergie radiante laser (11A, 11B, 215) physiquement dissocies adaptes, chacune, fournir une nergie d'excitation au gaz contenu dans la cuve, une longueur donde dmission diffrente correspondant une longueur d'onde d'absorption maximum localement pour un dit gaz, chaque dite source dnergie radiante tant positionne en regard dune fentre (52) fermant une extrmit de tube, - un moyen de modulation (17) qui module l'nergie d'excitation fournie par chacune des sources dnergie laser avec une frquence de modulation en correspondance avec la frquence de rsonance acoustique de la cuve rsonnante et - au moins un transducteur acousto-lectrique (20, 21) dispos sur lun des tubes pour dtecter les signaux acoustiques produits dans ce tube et fournir un signal lectrique reprsentatif de la concentration du gaz dans la cuve.
Abstract:
The present invention related to an optical fuel sensor (10). The fuel sensor (10) includes a sample container (22) for accommodating fuel while passing light having a wavelength from 420 nm to 700 nm. A light source (24) is provided for emitting light with a stronger intensity within a wavelength band from 420 nm to 520 nm than outside of it so as to irradiate the sample container (22) with the light. A light detector element (26) is also provided for receiving light radiated from the sample container (22) so as to generate an output upon receiving the light. The light detector (26) shows a stronger sensitivity within a wavelength band from 500 nm to 700 nm than outside of it.
Abstract:
An integrated optical component coupled to a circuit board of an aerosol sensor is provided. The integrated optical component comprising a medium including a first, second plane, third plane, wherein the first plane is adjacent to a detection area, the second plane is positioned about a photosensor, and the third plane is opposite an angle formed by an intersection of the first and second plane. The integrated optical component further comprising a first lens configured on the first sidewall, the first lens configured to receive incident light from the detection area and focus the incident light onto a reflector through the medium, the reflector configured on the third sidewall, the reflector configured to reflect the incident light towards a second lens, and the second lens configured on the second sidewall, the second lens configured to receive the incident light from the reflector and focus the incident light to the photosensor.
Abstract:
The invention relates to a measuring device for determining a vegetation index value (REIP) of plants. The measuring device comprises a plurality of light emitting elements, each of which emits substantially monochromatic light at a predetermined wavelength, a light receiving element which receives light from the light emitting elements reflected by the plants and generates a signal indicating the respective intensity of the received light, and a control means which successively activates the light emitting elements in a cyclical sequence, determines the respective intensity of the reflected light based on the output signal of the light receiving element, and calculates the vegetation index value based on the determined intensities of the overall measurement cycle. According to the invention, a light frequency converter is provided as the light receiving element.
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:
The infrared detecting element has a first base plate that has a first front surface, a first back surface, a first recessed portion, and an infrared detecting section for detecting infrared rays provided in an area of the first front surface that opposes the first recessed portion; a second base plate that has a second front surface, a second back surface on the opposite side of the second front surface, and a second recessed portion provided in an area of the second back surface that faces the first recessed portion; and an adhesion film that bonds the first back surface and the second back surface, wherein a second outer peripheral portion where the second recessed portion intersects with the second back surface surrounds a first outer peripheral portion where the first recessed portion intersects with the first back surface.