摘要:
A method and apparatus for the spectrochemical analysis of a sample in which a solid state array detector (82) is used to detect radiation (62) of spectrochemical interest. The invention involves the use of a shutter (72) adjacent the entrance aperture (70) of a polychromator (74-80) to expose the detector (82) to the radiation (62) for varying lengths of time whereby for short duration exposure times charge accumulation in elements (i.e. pixels) of the detector (82) due to high intensity components of the radiation is limited and for longer exposure times charge accumulation in elements (pixels) of the detector (82) due to feeble intesity components of radiation (62) is increased. This ensures that each reading of the detector (82) includes at least one exposure in which the amount of charge accumulated at each wavelength of interest is neither too little or too great. The problems of feeble radiation components not being accurately measurable and of high intensity radiation components exceeding the charge carrying capacity of elements (pixels) of the detector (82) are thereby able to be avoided. An attenuator (90) may be placed between the radiation source (60) and the detector (82) to permit longer exposure times to be used for very high intensity radiation.
摘要:
A system and method for generating signals representing infrared radiation include the capability to provide a reference scene (1008) and an actual scene (1016) to a plurality of infrared detector elements arranged in a two-dimensional array, the detector elements being biased so that they produce a signal even when no infrared radiation is impinging thereon (1004). The system and method further include the capability to receive a first signal representing the reference scene from one of the detector elements (1012), receive a second signal representing the actual scene from the detector element, and remove the bias signal from the second signal (1020). The system and method also include the capability to attenuate the remaining second signal (1024), integrate the attenuated signal (1028), and sample the integrated signal (1032).
摘要:
A chopper (41), in an infrared imaging system, is used to scatter infrared radiation from a viewed scene (11). This scattered radiation is detected with an infrared detector (14) and used to produce a reference signal, which represents the uniform average radiance of the scene. This reference signal may be subtracted from a signal representing the unscattered radiation emitted by the scene, to produce a signal that represents only radiance differences and that is an optimal signal for amplification.
摘要:
Bei einer Einrichtung zur Messung der aus dem Halbraum oder Raum kommenden elektromagnetischen Strahlung ist zur abwechselnden Abdeckung und Freigabe eines oder mehrerer Strahlungsdetektoren (D) und der zugeordneten, strahlungsdurchlässigen Abdeckhauben (K) ein relativ zu dem oder den Detektoren (D) bewegbarer Modulator (MO) in Form eines oder mehrerer kreisförmig gebogener hohler Halbzylinder (HZ) vorgesehen, die vorzugsweise am Rand einer drehbaren Scheibe (S) befestigt sein können. Ferner sind die halbkreisförmig gebogenen, hohlen Halbzylinder (HZ) im Querschnitt vorzugsweise halbkreisförmig, und können ferner auf ihrer Innenseite verspiegelt sein oder ein Emissionsvermögen nahe 1 aufweisen. Bei der Verwendung dieses Modulators (MO) sind so-mit in der Phase der Freigabe bei einem Detektor dieser jeweils der Strahlung des gesamten Halbraums bzw. bei zwei Detektoren (D), welche beispielsweise nach oben und unten diametral zueinander ausgerichtet angeordnet sind, diese Detektoren jeweils der Strahlung des gesamten Raums ausgesetzt. Ferner ist die Zugänglichkeit der Abdeckhaube (K) zu Reinigungszwecken problemlos, und die Antriebsvorrichtung (M) für den Modulator läßt sich in einfacher Weise ausführen. Besonders vorteilhaft ist, daß in einfacher Weise mehrere Meßgeräte zum Erfassen aus der dem Raumwinkel 2π entsprechenden Halbraum kommenden Strahlung betrieben werden können, wenn die Meßgeräte in verschiedene Richtungen ausgerichtet sind. Auch kann mit der erfindungsgemäßen Meßeinrichtung problemlos zenitnahe Strahlung von der Sonne erfaßt werden.
摘要:
A shutter assembly comprising a first planar member and a second planar member opposed from one another and forming a sleeve having a cavity therebetween, the sleeve having a pair of side rails adjacent the cavity along sides of the sleeve. A first shutter member having a first end is disposed in the cavity and slidingly disposed along one of the side rails, and a second shutter member having a second end is disposed in the cavity and slidingly disposed along the other side rail. The first end is opposed to the second end and is configured to be selectively advanced towards, and retracted from, the second end so as to define an aperture therebetween having a first shape when disposed in a first position, and wherein the aperture has a second larger shape when the first end is disposed in a second position. The first shutter member and the second shutter member maintain a thermal contact with the side rails and the planar members in all positions. The shutter assembly is well suited to be used at a cryogenic temperature and in a high vacuum environment.
摘要:
The invention relates to a detector without temperature regulation which comprises a matrix of suspended bolometers arranged in the focal plane of a lens, a reading circuit providing a flow of raw values, and a shutter. A method for correcting raw values comprises: after closing the shutter, a first step (102) of acquiring a common table of raw values; a second step (108) of determining a table of offset corrections for the current temperature of the detector according to the common table and a set of stored tables of raw values; and a third step (60) of correcting the flow of raw values by means of the table of corrections. According to the invention, a maintenance process (122, 103) comprises: testing a condition for replacing a table of said common set with the common table; if said condition is fulfilled, replacing the table of said common set with the common table. The test comprises establishing the existence of a new set of tables, resulting from the replacement of a table of the common set with the common table, which is more relevant than the common set for the purpose of subsequently establishing the offset table.
摘要:
An infrared imaging device is disclosed. Shut-off means (40) is closable and openable, and shuts off infrared radiation incident on an optical system (20) when it is in a close state. While the infrared imaging device is imaging, the shut-off means (40) is set in an open state, and the optical system (20) forms an infrared image of an object (70) on an infrared sensor (10) by focusing infrared radiation radiated from the object (70). The infrared sensor (10) outputs a signal corresponding to the amount of infrared radiation received by each pixel. Correction means (30) corrects the sensitivity variations of pixels and the effect of infrared radiation from the optical system (20). While the infrared imaging (40) device is calibrated, the shut-off means is set in a closed state, and correcting means (30) determines a correction coefficient for correcting the variation of the amount of infrared radiation from the optical system (20) by using the output of the infrared sensor (10) imaging the shut-off means (40).