Abstract:
Automatic zeroing apparatus zeroes an infrared gas analyzer automatically upon the occurrence of preselected conditions to indicate zero in the absence of absorption of infrared radiation by a gas mixture being analyzed. The gas analyzer has a sample cell for containing a gas mixture to be analyzed. Infrared radiation directed through the sample cell is detected at a preselected wavelength to produce a detection signal. A signal processor outputs a signal systematically related to the difference between the detection signal and a reference signal. For zeroing the sample cell is filled with gas substantially nonabsorbent of infrared radiation at the respective characteristic wavelength. A comparator produces an error signal when the output signal differs from zero. A gain control automatically controls the signal level of the detection signal to reduce the output signal substantially to zero with the nonabsorbent gas filling the sample cell. The preselected conditions may include the passage of a predetermined time and a temperature drift beyond a predetermined limit.
Abstract:
A spectroscopic device includes: an analysis optical system; a length measurement optical system; and a calculation device. The analysis optical system includes a moving mirror and a first light receiving element. The length measurement optical system includes a second light source configured to emit laser light, a gas cell with a gas that absorbs light of a predetermined wavelength sealed therein and configured to cause the laser light to be incident thereon, an emitted light amount detection unit configured to detect an amount of light emitted from the gas cell and output an emitted light amount detection signal, a light source control unit configured to control a wavelength of the laser light based on the emitted light amount detection signal, and a length measurement unit configured to use the laser light to obtain a displacement signal corresponding to a position of the moving mirror, and the calculation device includes a moving mirror position calculation unit, a light intensity calculation unit, and a Fourier transform unit configured to generate a spectral pattern.
Abstract:
A device may obtain a master beta coefficient of a master calibration model associated with a master instrument. The master beta coefficient may be at a grid of a target instrument. The device may perform constrained optimization of an objective function, in accordance with a set of constraints, in order to determine a pair of transferred beta coefficients. The constrained optimization may be performed based on an initial pair of transferred beta coefficients, the master beta coefficient, and spectra associated with a scouting set. The device may determine, based on the pair of transferred beta coefficients, a transferred beta coefficient. The device may determine a final transferred beta coefficient based on a set of transferred beta coefficients including the transferred beta coefficient. The final transferred beta coefficient may be associated with generating a transferred calibration model, corresponding to the master calibration model, for use by the target instrument.
Abstract:
An inspection system and method is provided herein for increasing the detection range of the inspection system. According to one embodiment, the inspection system may include a photodetector having a plurality of stages, which are adapted to convert light scattered from a specimen into an output signal, and a voltage divider network coupled for extending the detection range of the photodetector (and thus, the detection range of the inspection system) by saturating at least one of the stages. This forces the photodetector to operate in a non-linear manner. However, measurement inaccuracies are avoided by calibrating the photodetector output to remove any non-linear effects that may be created by intentionally saturating the at least one of the stages. In one example, a table of values may be generated during a calibration phase to convert the photodetector output into an actual amount of scattered light.
Abstract:
An inspection system and method is provided herein for increasing the detection range of the inspection system. According to one embodiment, the inspection system may include a photodetector having a plurality of stages, which are adapted to convert light scattered from a specimen into an output signal, and a voltage divider network coupled for extending the detection range of the photodetector (and thus, the detection range of the inspection system) by saturating at least one of the stages. This forces the photodetector to operate in a non-linear manner. However, measurement inaccuracies are avoided by calibrating the photodetector output to remove any non-linear effects that may be created by intentionally saturating the at least one of the stages. In one example, a table of values may be generated during a calibration phase to convert the photodetector output into an actual amount of scattered light.
Abstract:
Un appareil de remise à zéro automatique remet automatiquement à zéro un analyseur de gaz aux infra-rouges lorsque des conditions présélectionnées se produisent, afin d'indiquer l'état zéro en cas d'absorption nulle des rayonnements infra-rouges par un mélange de gaz en cours d'analyse. L'analyseur de gaz comprend une cellule d'échantillonage (11) qui contient un mélange de gaz que l'on veut analyser. Les rayonnements infra-rouges envoyés à travers la cellule d'échantillonnage (11) sont détectés à une longueur d'onde présélectionnée afin de produire un signal de détection. Un processeur de signaux sort des signaux systématiquement associés à la différence entre le signal de détection et un signal de référence. Pour la remise à zéro, la cellule d'échantillonnage (11) est remplie d'un gaz sensiblement non-absorbant des rayonnements infra-rouges à la longueur d'onde caractéristique respective. Un comparateur génère un signal d'erreur lorsque le signal de sortie diffère de zéro. Une commande de gain (DAC 21) commande automatiquement le niveau des signaux de détection afin de réduire le signal de sortie sensiblement à zéro lorsque le gaz non-absorbant remplit la cellule d'échantillonnage (11). Les conditions présélectionnées peuvent inclure l'écoulement d'une période de temps prédéterminée et une dérive de la température au-delß de limites prédéterminées.
Abstract:
Automatic zeroing apparatus zeroes an infrared gas analyzer automatically upon the occurrence of preselected conditions to indicate zero in the absence of absorption of infrared radiation by a gas mixture being analyzed. The gas analyzer has a sample cell (11) for containing a gas mixture to be analyzed. Infrared radiation directed through the sample cell (11) is detected at a preselected wavelength to produce a detection signal. A signal processor outputs a signal systematically related to the difference between the detection signal and a reference signal. For zeroing the sample cell (11) is filled with gas substantially nonabsorbent of infrared radiation at the respective characteristic wavelength. A comparator produces an error signal when the output signal differs from zero. A gain control (DAC 21) automatically controls the signal level of the detection signal to reduce the output signal substantially to zero with the nonabsorbent gas filling the sample cell (11). The preselected conditions may include the passage of a predetermined time and a temperature drift beyond a predetermined limit.
Abstract:
Automatic zeroing apparatus zeroes an infrared gas analyzer automatically upon the occurrence of preselected conditions to indicate zero in the absence of absorption of infrared radiation by a gas mixture being analyzed. The gas analyzer has a sample cell (11) for containing a gas mixture to be analyzed. Infrared radiation directed through the sample cell (11) is detected at a preselected wavelength to produce a detection signal. A signal processor outputs a signal systematically related to the difference between the detection signal and a reference signal. For zeroing the sample cell (11) is filled with gas substantially nonabsorbent of infrared radiation at the respective characteristic wavelength. A comparator produces an error signal when the output signal differs from zero. A gain control (DAC 21) automatically controls the signal level of the detection signal to reduce the output signal substantially to zero with the nonabsorbent gas filling the sample cell (11). The preselected conditions may include the passage of a predetermined time and a temperature drift beyond a predetermined limit.
Abstract:
An inspection system and method is provided herein for increasing the detection range of the inspection system. According to one embodiment, the inspection system may include a photodetector having a plurality of stages, which are adapted to convert light scattered from a specimen into an output signal, and a voltage divider network coupled for extending the detection range of the photodetector (and thus, the detection range of the inspection system) by saturating at least one of the stages. This forces the photodetector to operate in a non-linear manner. However, measurement inaccuracies are avoided by calibrating the photodetector output to remove any non-linear effects that may be created by intentionally saturating the at least one of the stages. In one example, a table of values may be generated during a calibration phase to convert the photodetector output into an actual amount of scattered light.