Abstract:
Various embodiments disclosed herein describe an infrared (IR) imaging system for detecting a gas. The imaging system can include an optical filter that selectively passes light having a wavelength in a range of 1585 nm to 1595 nm while attenuating light at wavelengths above 1600 nm and below 1580 nm. The system can include an optical detector array sensitive to light having a wavelength of 1590 that is positioned rear of the optical filter.
Abstract:
A method of measuring the temperature of a remote body which comprises determining the frequency range to be covered and the portion of that range or frequency band to be covered by each detector of a detector array or by a single detector via a filter for applying different frequency bands to the single detector. The required detector or detectors are then provided and sense the energy radiated by the remote body whose temperature is to be measured. The detector or detectors then provide an output of the amount of energy measured in each unique frequency band and sends these measured outputs to a processor. The processor receives the measured outputs from the detector(s) and determines therefrom in accordance with an algorithm thereat the measured temperature. The processor then provides an output indicative of the measured temperature.
Abstract:
A thermally insulating casing accommodates an infrared ray sensing element. The casing has a window which conducts infrared ray to the sensing element. The window is covered with heat absorption gas. An infrared ray emitting element may be accommodated within the casing. The casing may have a second window which passes infrared ray generated by the emitting element. The second window may be covered with the heat absorption gas.
Abstract:
A novel dual spectra optical pyrometer is characterized by a serial array of photodetectors. The first photodetector absorbs a spectral portion of a target optical beam incident thereto, and passes the remainder optical beam to the second photodetector. Signals from both photodetectors are provided along with signals indicative of the first detector's spectral absorption and an estimate of the equivalent black body temperature of a fireball to a signal processor which provides a compensated temperature signal therefrom.
Abstract:
Various embodiments disclosed herein describe an infrared (IR) imaging system for detecting a gas. The imaging system can include an optical filter that selectively passes light having a wavelength in a range of 1585 nm to 1595 nm while attenuating light at wavelengths above 1600 nm and below 1580 nm. The system can include an optical detector array sensitive to light having a wavelength of 1590 that is positioned rear of the optical filter.
Abstract:
A narrow-band pyrometric system measures the temperature of an object (1), such as a semiconductor wafer (1), that is coated with a film (2) having an absorption band. The thermal radiation emitted by the coated object (1) passes through a lens (3) and aperture (4), and then a filter (5). The passband of this filter (5) falls within the absorption band of the film (2). The transmitted radiation is then collected by the radiation detector (6), which measures the intensity. The detected radiation is at a wavelength where the heated object (1) is substantially opaque, and the effect of uncertainties in the emissivity on the temperature measurement is minimized. Thus, a method is provided to coat the object (1) with a film (2) of material having an absorption band encompassing the filter (5) passband, and a thickness sufficiently great that the object (1) appears opaque when viewed through the filter (5). Alternatively, the film (2) material and thickness must be such that the emissivity is constant and accurately known in the passband wavelength region.
Abstract:
A reflection corrected radiosity optical pyrometer includes an optical guide for receiving a target optical beam from a turbine blade in a jet engine. The target optical beam is provided to a detector module that divides the target optical beam into two beams, one having a spectral width selected to be less than the target optical beam spectral width. A signal processor receives signals from the detector module indicative of the energy of the two beams, calculates a reflection corrected energy signal directly therefrom and provides a correct target temperature signal.
Abstract:
Characteristics of a flame within a turbine or burner are determined based upon ultraviolet, visible, and infrared measurements of the flame. The measurements include a measurement of the amplitute of frequency bands that are indicative of an efficient combustion process, such as those that increase when the flame temperature increases. The measurements also include of the amplitude of frequency bands that are indicative of an inefficient combustion process, such as those that do not vary, increase a relatively small amount, or decrease when the flame temperature increases. The temperature of the flame may therefore be determined accurately, to facilitate efficient operation of the turbine or burner while minimizing polluting emissions. A fiber structure, suitable for remote location of sensors and processing equipment passes energy for several spectra by providing a hollow core that passes infrared energy, in combination with a core of visible-transmissive material that passes visible or ultraviolet energy. Contaminants in the turbine or burner are detected, and a degree of contamination measured, by detection of energy levels for particular wavelengths associated with a respective contaminant.
Abstract:
1. Procédé d'exploitation des signaux fournis par un pyromètre optique à deux voies caractérisé en ce que :
on définit pour chaque voie une bande passante optique large ; on prend en compte, aussi bien pour l'étalonnage que pour la mesure, la luminance énergétique du spectre reçu respectivement dans la première et dans la deuxième bande ; on étalonne le photodétecteur en se référant à un corps noir que l'on porte successivement à au moins deux températures connues, en calculant théoriquement ces luminances énergies à l'aide d'un ordinateur qui, à partir de la formule de Planck L = f(λ,T) effectue les intégrales
puis, à l'aide du pyromètre ainsi étalonné, on mesure les tensions électriques V i et V j fournies par la voie 1 et par la voie 2 du pyromètre lors de l'examen optique du corps ; on en déduit, par les fonctions V = g(L), les valeurs L A et L B de la luminance énergétique réellement reçue par chaque voie ; on recherche par itération à l'aide d'un ordinateur celle des courbes de Planck L=f(λ,T) dont les intégrales sont précisément égales aux luminances mesurées.
Abstract:
A thermally insulating casing (9) accommodates an infrared ray sensing element (2). The casing has a window (6) which conducts infrared rays to the sensing element. The window is covered with heat absorption gas (7). An infrared ray emitting element (1) may be accommodated within the casing (9). The casing may have a second window (3) which passes infrared ray generated by the emitting element. The second window may be covered with the heat absorption gas (7).