Abstract:
A pyrometer comprising light emitting means (101) for emitting light having at least two wavelengths to a target to be measured, first light measuring means for measuring light emitted by said light emitting means (101) with respect to said at least two wavelengths to produce first signals, second light measuring means for measuring light reflected by the target with respect to said at least two wavelengths to produce second signals, third light measuring means for measuring intensity of light radiated by the target with respect to said at least two wavelengths to produce third signals, emissivity assuming means for assuming an emissivity of the target on the basis of the equation ε (λ)= 1-k×L(λ) or ε (λ)= 1- k(λ) ×L(λ) , wherein ε (λ), k, k(λ), L(λ) respectively represents an assumed emissivity of the target with respect to a wavelength λ, a constant, a function of λ, information as to the second signal at λ, and temperature calculating means (107) for calculating a temperature of the target on the basis of the minimum value of the difference between an assumed radiation intensity calculated according to the assumed emissivity of the target and a measured radiation intensity according to the third signals. Due to the pyrometer, a true temperature can be calculated even when the actual spectral characteristic of emissivity is complicated, and measuring errors of the radiation intensity and reflection intensity etc. can be prevented.
Abstract:
La présente invention concerne un procédé de mesure de l'émissivité d'un corps à surface sensiblement lisse, comprenant les étapes suivantes : a) réalisation d'une première mesure A de la luminance en un point de la surface du corps sous un angle d'émission θ, le rayonnement thermique sur lequel est effectué la mesure étant polarisé dans une première direction par rapport au plan d'émission ; b) réalisation d'une seconde mesure B de la luminance au même point et sous le même angle θ, le rayonnement thermique sur lequel est effectué la mesure étant polarisé dans une seconde direction par rapport au plan d'émission, cette seconde direction étant différente de la première direction ; c) détermination de l'émissivité ε du corps, ledit procédé étant caractérisé en ce que l'angle θ est compris entre 40° et 50°, et l'émissivité non polarisée ε du corps et/ou la composante de l'émissivité dans le plan perpendiculaire ε S au plan d'émission et/ou la composante de l'émissivité dans le plan parallèle ε P au plan d'émission est déterminée sur la base des fonctions suivantes : ε = a 1 + 1 , 05 - B / A x 9 , 3332 × 10 - 8 x θ 5 - 2 , 6666 x 10 - 5 x θ 4 + 2 , 9883 x 10 - 3 x θ 3 - 0 , 16243 x θ 2 + 4 , 18573 x θ - 38 , 49 ε S θ = 2 - R ε P θ = 2 R - R 2 avec B A = R .
Abstract:
Die vorliegende Erfindung bezieht sich auf eine Temperaturerfassungseinrichtung eines Geräts zur berührungslosen Erfassung der Temperatur und/oder der Temperaturänderung eines Gegenstandes (4) insbesondere eines Kochgeschirrs mit thermisch durch das Gerät zu beaufschlagenden und/oder zu behandelnden Gargut, unter Verwendung zumindest eines den Gegenstand zumindest partiell erfassenden Infrarotstrahlungssensors (6). Der Temperaturerfassungseinrichtung ist ein in Richtung auf den temperaturmäßig zu erfassenden Gegenstand strahlender Infrarotstrahler (1) zugeordnet. Die vom zugeordneten Infrarotstrahler ausgesandte Strahlung wird von dem zu erfassenden Gegenstand reflektiert und zur Feststellung der Beschaffenheit des zu erfassenden Gegenstandes durch den Infrarotsender ausgewertet.
Abstract:
In a process for heating, e.g., a semiconductor wafer within a processing chamber, the wafer is exposed to a flux of electromagnetic radiation from lamps energized by alternating electric current. The surface temperature of the wafer is measured, and responsively, the radiation flux is controlled. The temperature measurement procedure includes collecting radiation propagating away from the wafer in a first light-pipe probe, collecting radiation propagating toward the wafer in a second light-pipe probe, and detecting radiation collected in the respective probes. This procedure further involves determining, in the signal received from each probe, a magnitude of a time-varying component resulting from time-variations of the energizing current, and combining at least these magnitudes according to a mathematical expression from which the temperature can be inferred. At least some of the radiation collected by the second probe is collected after reflection from a diffusely reflecting surface. The second probe effectively samples this radiation from an area of the diffusely reflecting surface that subtends a solid angle Ω₂ at the wafer surface. The first probe effectively samples radiation from an area of the wafer that subtends a solid angle Ω₁ at the first probe. The radiation sampling is carried out such that Ω₂ is at least about Ω₁.
Abstract:
Method and apparatus for accurately and instantaneously determining the thermodynamic temperature of remote objects by continuous determination of the emissivity, the reflectivity, and optical constants, as well as the apparent or brightness temperature of the sample with a single instrument. The emissivity measurement is preferably made by a complex polarimeter including a laser that generates polarized light, which is reflected from the sample into a detector system. The detector system includes a beamsplitter, polarization analyzers, and four detectors to measure independently the four Stokes vectors of the reflected radiation. The same detectors, or a separate detector in the same instrument, is used to measure brightness temperature. Thus, the instrument is capable of measuring both the change in polarization upon reflection as well as the degree of depolarization and hence diffuseness. This enables correction for surface roughness of the sample and background radiation, which could otherwise introduce errors in temperature measurement.
Abstract:
A method for measuring temperature based on infrared light which measures the temperature of a semiconductor element, the surface layer of which is formed with two kinds of materials having different emissivities and optical reflectances, based on the amount of infrared emission incident on an image taking means according to the invention, comprises the steps of taking an image by diffusing and letting the incident be the reflected light of a beam of light incident on the surface of the above semiconductor element on the light receiving face of the image taking means, followed by determining the area ratio at which each of the above two kinds of materials occupies the surface of the above semiconductor element by comparing the average brightness value of the above image with the brightness value of an image for the case that each of the above two kinds of materials independently forms the surface layer of the above semiconductor element, and obtaining the weighted average of the emissivities of the above two kinds of materials with the area ratio at which each of the above two kinds of materials occupies the surface of the above semiconductor element, followed by calculating the temperature of the above semiconductor element based on the weighted average and the actual amount of infrared emission.
Abstract:
A method of determining true temperatures of a heated target material by its radiation is based on prior knowledge of an emissivity function. This function describes the relationship between the two spectral emissivities for the target material. The method comprises the steps of measuring two radiances corresponding to said spectral emissivities from the target material, assuming a temperature of the target material, then calculating a pair of emissivities which satisfy the emissivity function whereat the assumed temperature is the true temperature of the target material.