5 résultats pour "ccd"
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Le capteur CCD
Au fur et à mesure que les électrons sortent, un registre électronique mémorise le contenu de chaque tas, ainsi que leurs coordonnées, afin d'identifier le pixel d’où vient le tas. Avec ces données, l’image formée par l’objectif sur le capteur CCD peut être reconstruite par l’ordinateur comme une mosaïque dont les éléments sont des pixels. Voici une photo de saturne prise de la terre à l’aide d’un capteur CCD : PHOTO DE SATURNE 1.3 Différents types de capteurs CCD - Matrices l...
- CCD, capteur - physique.
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Television.
A charge-coupled device (CCD) can be much smaller than a camera tube and is much more durable. As a result, cameras with CCDs are more compact and portablethan those using a camera tube. The image they create is less vulnerable to distortion and is therefore clearer. In a CCD, the light from a scene strikes an array ofphotodiodes arranged on a silicon chip. Photodiodes are devices that conduct electricity when they are struck by light; they send this electricity to tiny capacitors. Thecapacitors...
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Observatory - astronomy.
Ultraviolet radiation, X rays, and gamma rays have shorter wavelengths than visible light has. These types of radiation tell astronomers about the hottest and mostviolent phenomena in the universe. Earth’s atmosphere blocks most of this radiation, so astronomers must send their observatories above the atmosphere aboardballoons, rockets, or satellites. Ultraviolet telescopes are much like visible light telescopes, but X-ray telescopes must have special nested cylindrical mirrors to prevent Xrays...
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Telescope - astronomy.
Observatory). In some telescopes designed in the 1990s, the mirror’s weight has been dramatically reduced by sandwiching a honeycomb pattern of glass ribs between a thin, butrigid, concave mirror and a flat back plate. Engineers have even developed meniscus mirrors—mirrors that are too thin to support their own weight. An adjustableframework supports the meniscus mirror, and servomechanical actuators, controlled by computer, continually adjust the shape of the mirror as it tracks celestial tar...