JP2020085696A - Infrared detection device, infrared detection method, program to be executed by computer, and computer-readable recording medium in which program is recorded - Google Patents

Abstract

To provide an infrared detection device with which it is possible to calculate a temperature with high accuracy even in a far-infrared and a mid-infrared region.SOLUTION: An infrared detection device 10 comprises detectors 1, 2 and a calculation unit 4. The detection 1 detects the spectral irradiance I (λ, T) of an infrared ray IFR1 having a wavelength λ. The detector 2 detects the spectral irradiance I (λ, T) of an infrared ray IFR2 having a wavelength λlonger than the wavelength λ. The calculation unit 4 calculates, on the basis of the ratio of spectral irradiances I (λ, T) and I(λ, T), the ratio of the permeability τ(λ) of the infrared ray IFR1 in a section from an object 20 to the detectors 1, 2 to the permeability τ(λ) of the infrared ray IFR2 in a section from the object 20 to the detectors 1, 2, calculates the permeability of either τ(λ) or τ(λ) on the basis of the calculated permeability ratio, and calculates the temperature of the object 20 on the basis of the calculated permeability.SELECTED DRAWING: Figure 1

Description

The present invention relates to an infrared detection device, an infrared detection method, a program to be executed by a computer, and a computer-readable recording medium recording the program.

At present, infrared detectors that detect radiant energy of infrared rays are widely used as components of radiation thermometers and gas sensors. A radiation thermometer is a device that converts infrared radiant energy that can be measured in a non-contact manner into the temperature of a target object.A gas sensor observes the attenuation rate until the infrared energy of the target object reaches the infrared detector and measures the gas concentration. It is a device that converts to.

For radiation thermometers and gas sensors, various device configurations, methods for calculating temperature and gas concentration are known. The reason for this is that the radiant energy of infrared rays is influenced by the temperature of the object, the transmittance between the object and the infrared detector, and the emissivity of the object.

In the radiation thermometer, the method of estimating the temperature from the radiant energy of infrared rays is classified by the number of wavelengths detected by the infrared detector. As a typical method, a monochromatic method that detects radiant energy of a single wavelength and converts its intensity into temperature, a two-color method that detects radiant energy of two wavelengths and converts the ratio of radiant energy into temperature It has been known. On the other hand, there is also known a multicolor method in which radiant energy of three or more wavelengths is detected to calculate temperature.

In order to calculate the temperature with high accuracy by these temperature calculating methods, the prerequisites of the respective measuring methods must be satisfied. For example, in the monochromatic method, the temperature cannot be calculated with high accuracy unless the emissivity of the object and the transmittance between the object and the infrared detector are known. On the other hand, in the two-color method, when the emissivity of the object and the transmittance between the object and the infrared detector do not depend on the wavelength, the temperature can be calculated with high accuracy.

Patent Documents 1 and 2 and the like describe methods for calculating temperature with high accuracy even when the emissivity of an object and the transmittance between the object and an infrared detector depend on the wavelength. The multicolor method of Patent Document 1 is a method of calculating a temperature by correcting the emissivity having wavelength dependence by calculating the emissivity ratio for a high-temperature object. On the other hand, there is also a method of correcting the transmittance having wavelength dependency by using another detector. For example, Patent Document 2 is a radiation thermometer in which a water vapor transmission effect is corrected by a hygrometer.

JP, 7-146179, A JP, 2014-182122, A JP-A-7-113746 JP, 2009-8527, A

However, when the emissivity of the target object and the transmittance between the target object and the infrared detector have wavelength dependency, certain limited measurement conditions are required to calculate the temperature with high accuracy. The method of Patent Document 1 can be used only when the spectral radiance emitted by the object can be approximated by Wien's law, that is, when the detection wavelength of the infrared detector is a short wavelength. For example, when the temperature of the object is 780° C., the temperature can be calculated by correcting the wavelength-dependent emissivity using an infrared detector that detects a wavelength of 1.4 to 1.8 μm. .. That is, the method of Patent Document 1 cannot be used for an object at room temperature (0 to 100° C.) or an infrared detector in the far infrared region. On the other hand, according to the method of Patent Document 2, the temperature can be calculated with high accuracy by correcting the water vapor permeability. However, a hygrometer is required as an additional measuring device, which complicates the device.

Therefore, according to the embodiment of the present invention, there is provided an infrared detection device capable of calculating temperature with high accuracy even in the far infrared region and the mid infrared region.

Further, according to the embodiment of the present invention, there is provided an infrared detecting method capable of calculating temperature with high accuracy even in the far infrared region and the mid infrared region.

Further, according to the embodiment of the present invention, there is provided a program for causing a computer to execute highly accurate temperature calculation even in the far infrared region and the mid infrared region.

Further, according to the embodiment of the present invention, there is provided a computer-readable recording medium in which a program for causing a computer to execute highly accurate temperature calculation in the far infrared region and the mid infrared region is recorded.

(Structure 1)
According to the embodiment of the present invention, the infrared detecting device detects at least one of the temperature of the object, the absolute amount of the absorber existing between the object and the infrared detector, and the concentration of the absorber. An infrared detector, which includes first and second detectors and a calculator. The first detector detects a first spectral irradiance of a first infrared ray having a first wavelength. The second detector detects a second spectral irradiance of a second infrared ray having a second wavelength longer than the first wavelength. The calculator calculates a first spectral irradiance ratio, which is a ratio of the first spectral irradiance and the second spectral irradiance, from the object to the first and second detectors. A first transmittance, which is the infrared transmittance of the second infrared ray, and a second transmittance, which is the second infrared ray transmittance between the object and the first and second detectors. A transmittance ratio is calculated, a third transmittance that is either one of the first transmittance and the second transmittance is calculated based on the calculated first transmittance ratio, and the calculated third transmittance is calculated. At least one of the temperature of the object, the absolute amount of the absorber, and the concentration of the absorber is calculated based on the transmittance of the.

(Structure 2)
In the configuration 1, the calculation unit uses the relationship between the infrared transmittance and the black body spectral radiance and the spectral irradiance, and based on the third transmittance, the temperature of the object, the absolute amount of the absorber, and the absorption. At least one of the body concentrations is calculated.

(Structure 3)
In the configuration 2, the calculating unit is a detection ratio that is a ratio of the spectral radiance emitted by the object detected by the first and second detectors, and an emissivity of the first infrared ray from the object. The first black body spectral radiance, which is the black body spectral radiance at the first wavelength, is calculated based on the first emissivity, the third transmittance, and the first spectral irradiance. At least one of the temperature of the object, the absolute amount of the absorber, and the concentration of the absorber is calculated based on the calculated first black body spectral radiance.

(Structure 4)
In any one of Configuration 1 to Configuration 3, the calculation unit is a ratio of a first infrared absorption coefficient and a second infrared absorption coefficient between the object and the first and second detectors. The third transmittance is calculated based on the first transmittance ratio using the relationship among the parameter of 1, the first transmittance ratio, and the third transmittance.

(Structure 5)
In any one of Configuration 1 to Configuration 4, the calculation unit further calculates the temperature of the target object and the concentration of water vapor existing between the target object and the detector based on the third transmittance, The actual temperature is calculated from the water vapor concentration and the temperature of the object. Then, the first wavelength is set in the range of 3.5 to 6.0 μm, and the second wavelength is set in the range of 4.5 to 6.0 μm, or the first wavelength is The second wavelength is set to the range of 6.0 to 8.0 μm, or the first wavelength is set to the range of 3.5 to 4.5 μm. The second wavelength is set to the range of 13.0 to 16.0 μm, or the first wavelength is set to the range of 8.0 to 16.0 μm, and The wavelength of 2 is set in the range of 13.0 to 16.0 μm.

(Structure 6)
In any one of Configuration 1 to Configuration 4, the calculation unit further calculates the temperature of the target object and the concentration of carbon dioxide existing between the target object and the detector based on the third transmittance. Calculate an index of comfort from the concentration of carbon dioxide and the temperature of the object. The first wavelength is set in the range of 3.5 to 4.0 μm, and the second wavelength is set in the range of 4.0 to 4.5 μm, or the first wavelength is The second wavelength is set in the range of 3.5-16.0 μm, or the first wavelength is set in the range of 4.5-16.0 μm. And the second wavelength is set in the range of 13.5 to 16.0 μm.

(Structure 7)
In any one of Configuration 1 to Configuration 4, the calculation unit calculates the first black body spectral radiance that is the black body spectral radiance at the first wavelength and the second black body spectral radiance that is the second wavelength. The first transmittance ratio is calculated based on the first spectral irradiance ratio using the approximate value of the ratio with the black body spectral radiance.

(Structure 8)
In Configuration 1, the infrared detection device further includes a third detector. The third detector detects a third spectral irradiance of a third infrared ray having a third wavelength shorter than the first wavelength. The calculation unit approximates the ratio of the first black body spectral radiance that is the black body spectral radiance at the first wavelength and the second black body spectral radiance that is the black body spectral radiance at the second wavelength. The first transmittance ratio is calculated based on the first spectral irradiance ratio using the values, and the third transmittance is calculated from the calculated first transmittance ratio. The fourth transmittance, which is the transmittance of the third infrared ray between the second and third detectors, is calculated from the third transmittance, and the calculated fourth transmittance and third transmittance are calculated. Based on the above, at least one of the temperature of the object, the absolute amount of the absorber and the concentration of the absorber is calculated.

(Configuration 9)
In the configuration 7 or the configuration 8, the first and second wavelengths are longer than the peak wavelength at which the maximum value of the black body spectral radiance is obtained.

(Configuration 10)
In Configuration 8, the calculation unit includes a second parameter that is a ratio of the first infrared absorption coefficient and the third infrared absorption coefficient from the object to the first, second, and third detectors. Then, the fourth transmittance is calculated from the third transmittance by using the relationship between the third transmittance and the fourth transmittance.

(Configuration 11)
In the configuration 8 or the configuration 10, the calculation unit causes the calculation unit to calculate a second transmittance ratio, which is a ratio between the third transmittance and the fourth transmittance, and a ratio between the first spectral irradiance and the third spectral irradiance. And the ratio of the first emissivity, which is the emissivity of the object at the first wavelength, to the second emissivity, which is the emissivity of the object at the third wavelength, Based on a certain emissivity ratio, a first blackbody spectral radiance that is a blackbody spectral radiance at a first wavelength and a second blackbody spectral radiance that is a blackbody spectral radiance at a third wavelength. The black body spectral radiance ratio, which is the ratio of the two, is calculated, and at least one of the temperature of the object, the absolute amount of the absorber, and the concentration of the absorber is calculated based on the relationship between the calculated black body spectral radiance ratio and the temperature. To calculate.

(Configuration 12)
In any one of Configuration 7 to Configuration 11, the calculation unit further calculates the temperature of the target object and the concentration of water vapor existing between the target object and the detector based on the third transmittance, The actual temperature is calculated from the water vapor concentration and the temperature of the object. Then, the first wavelength is set in the range of 3.5 to 6.0 μm, and the second wavelength is set in the range of 4.5 to 6.0 μm, or the first wavelength is It is set in the range of 8.0 to 16.0 μm, and the second wavelength is set in the range of 13.0 to 16.0 μm.

(Configuration 13)
In any one of the configurations 7 to 11, the calculation unit further calculates the temperature of the target object and the concentration of carbon dioxide existing between the target object and the detector based on the third transmittance. Calculate the comfort index from the concentration of carbon dioxide and the temperature of the object. The first wavelength is set in the range of 3.5 to 4.0 μm, and the second wavelength is set in the range of 4.0 to 4.5 μm, or the first wavelength is The wavelength is set in the range of 4.5 to 16.0 μm, and the second wavelength is set in the range of 13.5 to 16.0 μm.

(Configuration 14)
In Structure 8, two or three detectors among the first to third detectors are one detector of a quantum well type or a quantum dot type, and the infrared detection device is applied to one detector. It further comprises a control unit for controlling the voltage to be controlled to control the wavelength of infrared rays to be detected to be two wavelengths or three wavelengths of the first to third wavelengths.

(Configuration 15)
In Configuration 1, the first and second detectors arranged in an array form a detector group. The calculation unit executes a process of calculating a first transmittance ratio based on the first spectral irradiance ratio for a plurality of sets of first and second spectral irradiances detected by a plurality of detector groups. A plurality of first transmittance ratios are calculated, a plurality of third transmittances are calculated based on the plurality of first transmittance ratios, and a plurality of regions of the object are calculated based on the plurality of third transmittances. A plurality of temperatures in the above are calculated, and the temperature distribution of the object is calculated based on the calculated plurality of temperatures.

(Configuration 16)
In the configuration 8, the first to third detectors arranged in an array form a detector group. The calculation unit executes a process of calculating a first transmittance ratio based on the first spectral irradiance ratio using the approximate value for a plurality of first spectral irradiance ratios, and then performs a plurality of first transmittances. Calculating a ratio, calculating a plurality of third transmittances from the plurality of first transmittance ratios, calculating a plurality of fourth transmittances from the plurality of third transmittances, and calculating a plurality of third transmittances. The plurality of temperatures in the plurality of regions of the object are calculated based on the rate and the plurality of fourth transmittances, and the temperature distribution of the object is calculated based on the calculated plurality of temperatures.

(Configuration 17)
Further, according to the embodiment of the present invention, the infrared detection method determines at least one of the temperature of the object, the absolute amount of the absorber existing between the target and the infrared detector, and the concentration of the absorber. A detection method for detecting, comprising a first spectral irradiance of a first infrared ray having a first wavelength and a second spectral irradiance of a second infrared ray having a second wavelength longer than the first wavelength. The first and second infrared rays from the object based on the first step of detecting the illuminance and the first spectral irradiance ratio which is the ratio of the first spectral irradiance and the second spectral irradiance. Is the ratio of the first transmittance, which is the first infrared transmittance between the detector and the detector, to the second transmittance, which is the second infrared transmittance between the object and the detector. A second step of calculating the first transmittance ratio and a third transmittance which is one of the first transmittance and the second transmittance based on the calculated first transmittance ratio. A third step of calculating and a fourth step of calculating at least one of the temperature of the object, the absolute amount of the absorber, and the concentration of the absorber based on the calculated third transmittance are provided.

(Structure 18)
In the second step of the configuration 17, the first transmittance ratio is the first black body spectral radiance which is the black body spectral radiance at the first wavelength and the black body spectral radiance at the second wavelength. It is calculated based on the first spectral irradiance ratio using an approximate value of the ratio with the second black body spectral radiance.

(Structure 19)
In Structure 17, the detection method is such that the fourth transmittance, which is the transmittance of the third infrared ray having the third wavelength shorter than the first wavelength between the object and the detector, is changed to the third transmittance. The fifth step of calculating from And a sixth step of calculating a fourth transmittance, which is the transmittance of the third infrared ray between the object and the detector, from the third transmittance. Then, in the first step, the third spectral irradiance of the third infrared is further detected. In the second step, the first transmittance ratio is the first black body spectral radiance which is the black body spectral radiance at the first wavelength and the black body spectral radiance at the second wavelength. It is calculated based on the first spectral irradiance ratio using an approximate value of the ratio of 2 to the black body spectral radiance. Further, in the fourth step, at least one of the temperature of the object, the absolute amount of the absorber, and the concentration of the absorber is calculated based on the third transmittance and the fourth transmittance.

(Configuration 20)
In the second step of the configuration 19, the first transmittance ratio is longer than the first spectral irradiance and the peak wavelength at the first wavelength longer than the peak wavelength at which the maximum value of the black body spectral radiance is obtained. It is calculated based on the second spectral irradiance at the second wavelength.

(Configuration 21)
In a fourth step of the configuration 19, at least one of the temperature of the object, the absolute amount of the absorber and the concentration of the absorber is a ratio of the third transmittance and the fourth transmittance. The transmittance ratio, the second spectral irradiance ratio that is the ratio of the first spectral irradiance and the third spectral irradiance, and the first emissivity that is the emissivity of the object at the first wavelength and the object The first black body spectral radiation, which is the black body spectral radiance at the first wavelength, calculated on the basis of the emissivity ratio, which is the ratio of the object to the second emissivity at the third wavelength. It is calculated based on the relationship between the temperature and the ratio between the luminance and the second black body spectral radiance that is the black body spectral radiance at the third wavelength.

(Configuration 22)
In the configuration 17, the first detector that detects the first infrared light and the second detector that detects the second infrared light are arranged in an array to form a detector group. Then, in the first step, each of the plurality of detector groups detects the first and second spectral irradiances, and in the second step, based on the first and second spectral irradiances, A process of calculating the transmittance ratio of 1 is performed on a plurality of sets of first and second spectral irradiances to calculate a plurality of first transmittance ratios, and in a third step, a plurality of first transmittances is calculated. A plurality of third transmittances are calculated based on the ratios, and in a fourth step, a plurality of temperatures in a plurality of regions of the object are calculated based on the plurality of third transmittances, and the calculated plurality of temperatures are calculated. The temperature distribution of the object is calculated based on the temperature.

(Structure 23)
In the configuration 19, the first detector that detects the first infrared light, the second detector that detects the second infrared light, and the third detector that detects the third infrared light are arranged in an array. Configure a detector group. Then, in the first step, each of the plurality of detector groups detects the first to third spectral irradiances, and in the second step, based on the first spectral irradiance ratio using an approximate value. And calculating a first transmittance ratio for a plurality of sets of first and second spectral irradiances to calculate a plurality of first transmittance ratios, and calculating a plurality of first transmittance ratios in the third step. A plurality of third transmittances are calculated based on the transmittance ratio of, a plurality of fourth transmittances are calculated from a plurality of third transmittances in a fifth step, and a plurality of third transmittances are calculated in a fourth step. The plurality of temperatures in the plurality of regions of the object are calculated based on the third transmittance and the plurality of fourth transmittances, and the temperature distribution of the object is calculated based on the calculated plurality of temperatures.

(Configuration 24)
Further, according to the embodiment of the present invention, the program causes the computer to detect at least one of the temperature of the object, the absolute amount of the absorber existing between the object and the infrared detector, and the concentration of the absorber. And a second infrared ray having a second wavelength longer than the first wavelength, the first spectral irradiance of the first infrared ray having the first wavelength, and the second infrared ray having a second wavelength longer than the first wavelength. The second spectral irradiance of the first spectral irradiance and the calculation means based on the first spectral irradiance ratio, which is a ratio of the first spectral irradiance to the second spectral irradiance. A first transmittance that is a first infrared transmittance between the object and the first and second infrared detectors, and a second transmittance that is a second infrared transmittance between the object and the detector. A second step of calculating a first transmittance ratio, which is a ratio with the transmittance of 2; and a calculating means, based on the calculated first transmittance ratio, one of the first and second transmittances. The third step of calculating the third transmittance, which is one of the transmittances, and the calculating means calculates the temperature of the target object, the absolute amount of the absorber, and the concentration of the absorber based on the calculated third transmittance. And a program for causing a computer to execute the fourth step of calculating at least one.

(Structure 25)
In the configuration 24, the calculation means, in the second step, the first black body spectral radiance which is the black body spectral radiance at the first wavelength and the second black body spectral radiance which is the second wavelength. The first transmittance ratio is calculated based on the first spectral irradiance ratio using the approximate value of the ratio with the black body spectral radiance.

(Configuration 26)
Further, according to the embodiment of the present invention, the recording medium is a computer-readable recording medium in which the program according to the configuration 24 or the configuration 25 is recorded.

It is possible to calculate the temperature with high accuracy in the far infrared region and the mid infrared region.

1 is a schematic diagram of an infrared detection device according to a first embodiment of the present invention. 4 is a flowchart for explaining the detection method according to the first embodiment for detecting the temperature of an object and/or the absolute amount or concentration of an absorber. It is a figure which shows the relationship between a transmittance and a wavelength. It is a figure which shows the temperature difference of the temperature of the set target object and the calculated temperature obtained by simulation. It is a figure which shows the relationship between the transmittance|permeability of water vapor and wavelength. It is a figure which shows the transmittance|permeability of the carbon dioxide in a certain humidity, and the relationship of a wavelength. FIG. 6 is a schematic diagram of an infrared detection device according to a second embodiment. It is a figure which shows the relationship between spectral radiance and wavelength. 9 is a flowchart for explaining a detection method according to the second embodiment for detecting the temperature of an object and/or the absolute amount or concentration of an absorber. It is a flowchart which shows the selection method which selects _two wavelength (lambda) ₂ ,(lambda) ₃ based on the accuracy rating of a radiation thermometer and the measuring range of the temperature of a target object. It is a flowchart which shows another selection method which selects _two wavelength (lambda) ₂ ,(lambda) ₃ based on the accuracy rating of a radiation thermometer, and the measuring range of the temperature of a target object. 7 is a flowchart showing a detection method for detecting the temperature of an object in the second embodiment. It is a figure which shows the temperature difference of the temperature of the set target object and the calculated temperature obtained by simulation. It is a figure which shows the temperature difference between the temperature of the set target object and the correction|amendment calculated temperature obtained by simulation. FIG. 9 is a schematic diagram of an infrared detection device according to a third embodiment. 9 is a flowchart for explaining a detection method according to a third embodiment for detecting the temperature of an object and/or the absolute amount or concentration of an absorber. It is a figure which shows the temperature difference of the temperature of the set target object and the calculated temperature obtained by simulation. 1 is a schematic view of an infrared detection device for detecting a temperature distribution of an object and/or an absolute amount distribution or a concentration distribution of an absorber existing between the object and an infrared detector according to an embodiment of the present invention. is there. 19 is a flowchart for explaining the operation of the infrared detection device shown in FIG. 18.

Embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts will be denoted by the same reference characters and description thereof will not be repeated.

[Embodiment 1]
1 is a schematic diagram of an infrared detection device according to a first embodiment of the present invention. Referring to FIG. 1, infrared detection device 10 according to the first exemplary embodiment includes detectors 1 and 2 and calculation unit 4.

The detectors 1 and 2 detect infrared rays belonging to a wavelength range of 3 to 16 μm from mid infrared to far infrared. More specifically, the detector 1 detects the spectral irradiance I(λ ₁ , T) of the infrared IFR ₁ having the wavelength λ ₁ belonging to the wavelength range of 3 to 16 μm among the infrared rays emitted from the object 20. Then, the detected spectral irradiance I(λ ₁ , T) is output to the calculation unit 4. The detector 2 detects the spectral irradiance I(λ ₂ , T) of the infrared IFR ₂ having the wavelength λ ₂ (>λ ₁ ) belonging to the wavelength range of 3 to 16 μm among the infrared rays emitted from the object 20. , And outputs the detected spectral irradiance I(λ ₂ , T) to the calculation unit 4.

The wavelengths λ ₁ and λ ₂ may include a certain wavelength range. In this case, the wavelengths λ ₁ and λ ₂ mean that the center wavelengths are the wavelengths λ ₁ and λ ₂ . The narrower the wavelength range, the higher the temperature detection accuracy.

The calculation unit 4 includes a brightness table 41 and a transmittance calculation table 42. The brightness table 41 includes a relationship BT1 between the value of the black body spectral radiance at the wavelength λ ₁ and the temperature T, and a relationship BT2 between the value of the black body spectral radiance at the wavelength λ ₂ and the temperature T. The transmittance calculation table 42 includes the relationship between the transmittance ratio and the transmittance.

The calculation unit 4 receives the spectral irradiance I(λ ₁ , T) from the detector 1 and the spectral irradiance I(λ ₂ , T) from the detector 2. Then, the calculation unit 4 uses the luminance table 41 and the transmittance calculation table 42 to measure the object 20 based on the spectral irradiances I(λ ₁ , T) and I(λ ₂ , T) by the method described later. The temperature T and/or the absolute amount or concentration of the absorber ABS existing between the object 20 and the detectors 1 and 2 is calculated.

Each of the detectors 1 and 2 is a detector that performs photoelectric conversion with an InGaAs bandgap, a detector including a thermal detector such as a bolometer and a wavelength filter, and energy levels of quantum dots stacked in multiple layers. And a quantum dot detector that performs photoelectric conversion by utilizing the above, and a quantum well detector that performs photoelectric conversion by utilizing the energy levels of quantum wells laminated in multiple layers.

The detectors 1 and 2 may be the same or different from each other. When the detectors 1 and 2 are the same, that is, when the two detectors 1 and 2 are constituted by one detector, the detectors 1 and 2 are quantum dot type detectors or quantum well type detectors. Become. The quantum dot detector or the quantum well detector can control the detection wavelength according to the applied voltage. As a result, only one detector is required, so that the infrared detection device 10 can be downsized and reduced in cost. When the two detectors 1 and 2 are configured by one detector, the infrared detection device 10 detects the voltage V ₁ for setting the wavelength to be detected to the wavelength λ ₁ (a quantum dot detector or a quantum dot detector). Control unit for applying a voltage V ₂ for setting the wavelength to be detected to the wavelength λ ₂ to the detector (comprising a quantum dot detector or a quantum well detector) Is further provided.

[Calculation method of target temperature]
The spectral irradiance I(λ ₁ , T) detected by the detector 1 is represented by the following equation.

In Equation (1), α is the detection ratio, τ(λ ₁ ) is the transmittance, and ε(λ ₁ ) is the emissivity. B(λ ₁ , T) is the blackbody spectral radiance at wavelength λ ₁ and temperature T.

The detection ratio α is a ratio of the spectral radiance detected by the detector 1 or the detector 2 to the spectral radiance emitted by the object 20. Then, the detection ratio α is determined by the shape of the target object 20, the distance between the target object 20 and the detectors 1 and 2, and the orientations of the detectors 1 and 2. In the embodiment of the present invention, the detectors 1 and 2 may be calibrated to determine the detection ratio α, or a design value determined by the focal length of the lens or the like may be used as the detection ratio α.

The transmittance τ(λ ₁ ) is the transmittance of the infrared IFR1 between the object 20 and the detectors 1 and 2, and the spectral radiance emitted by the object 20 propagates to the detectors 1 and 2 through the optical path. It is the ratio that is done.

The emissivity ε(λ ₁ ) is the ratio of the spectral radiance emitted by the object 20 to the blackbody spectral radiance in thermal radiation at the wavelength λ ₁ .

The black body spectral radiance B(λ ₁ , T) shown in Expression (1) is expressed by the following expression (Planck's expression).

In equation (2), h is Planck's constant, c is the speed of light, k is the Boltzmann's constant, and T is the absolute temperature.

The equations (1) and (2) described above also hold for the spectral irradiance I(λ ₂ , T) detected by the detector 2.

Therefore, the following equation is obtained from the equation (1) for the spectral irradiance I(λ ₁ , T) and the equation (1) for the spectral irradiance I(λ ₂ , T).

Thus, the transmittance ratio τ(λ ₁ )/τ(λ ₂ ) is the spectral irradiance ratio I(λ ₁ , T)/I(λ ₂ , T) and the emissivity ratio ε(λ ₂ )/Ε(λ ₁ ) and the black body spectral radiance ratio B(λ ₂ ,T)/B(λ ₁ ,T).

In the first embodiment, it is assumed that the emissivities ε(λ ₁ ) and ε(λ ₂ ) are known. The spectral irradiance ratio I(λ ₁ , T)/I(λ ₂ , T) is calculated from the spectral irradiances I(λ ₁ , T) and I(λ ₂ , T) detected by the detectors 1 and 2, respectively. It can be calculated. Regarding the black body spectral radiances B(λ ₁ , T) and B(λ ₂ ,T), based on the relationships BT1 and BT2 included in the luminance table 41, the black body spectral radiance B(λ _{1 at} a certain temperature Tx. , T) and B(λ ₂ , T) can be obtained.

Therefore, the transmittance ratio τ(λ ₁ )/τ(λ ₂ ) can be calculated by the equation (3). Further, according to the formula (3), the transmittance ratio τ(λ ₁ )/τ(λ ₂ ) is determined only by the temperature T.

In the first embodiment, the method of calculating the transmittance is used when there is a correspondence between the transmittance ratio and the transmittance. As an example of this, a law relating to the attenuation of infrared rays in the presence of an absorber, such as Lambert-Beer's law, can be applied.

Lambert-Beer's law is expressed by the following equation.

In Expression (4), ε _a (λ ₁ ) is the extinction coefficient of the infrared IFR1 having the wavelength λ ₁ . c _a is the concentration of the absorber ABS existing between the object 20 and the detectors 1 and 2. l is the distance from the object 20 to the detectors 1 and 2.

Equation (4), since also holds for transmittance tau (lambda _2), and Equation (4) for the transmission tau (lambda _1), by the equation (4) for the transmission tau (lambda _2), Clearing the concentration c _a and the distance l, the following equation is obtained.

Equation (5) means that the transmittance τ(λ ₁ ) can be calculated from the transmittance ratio τ(λ ₂ )/τ(λ ₁ ). In the first embodiment, the extinction coefficients ε _a (λ ₁ ) and ε _a (λ ₂ ) are known.

The transmittance calculation table 42 includes the relationship between the transmittance ratio τ(λ ₂ )/τ(λ ₁ ) and the transmittance τ(λ ₁ ). That is, the transmittance calculation table 42 calculates beforehand the relationship between the transmittance ratio τ(λ ₂ )/τ(λ ₁ ) and the transmittance τ(λ ₁ ) in the environment where the detectors 1 and 2 are used. Then, the relationship between the calculated transmittance ratio τ(λ ₂ )/τ(λ ₁ ) and the transmittance τ(λ ₁ ) is included.

Therefore, the calculation unit 4 calculates the transmittance ratio τ(λ ₁ )/τ(λ ₂ ) by the above-described formula (3), and the known extinction coefficients ε _a (λ ₁ ), ε _a (λ ₂ ). ), the extinction coefficient ratio ε _a (λ ₂ )/ε _a (λ ₁ ) is calculated, and the calculated reciprocal of the transmittance ratio τ(λ ₁ )/τ(λ ₂ ) and the extinction coefficient ratio ε _The transmittance τ(λ ₁ ) is calculated by substituting _a (λ ₂ )/ε _a (λ ₁ ) into the equation (5). Further, calculator 4, the formula (3) by the transmittance ratio _{τ (λ 1) / τ (} λ 2) of the transmittance on the basis of the transmittance calculating table 42 and calculates the ratio tau (lambda ₁₎ / tau ( by detecting the transmittance τ (λ ₁₎ corresponding to lambda _2), the ratio of the transmittance τ (λ ₁₎ / τ is calculated transmittance τ (λ ₁₎ from (lambda _2).

When calculating the transmittance τ(λ ₁ ), the calculator 4 calculates the calculated transmittance τ(λ ₁ ), the known detection ratio α, and the spectral irradiance I(λ ₁ , T detected by the detector ₁ . ), and the known emissivity ε(λ ₁ ) is substituted into the equation (1) to calculate the blackbody spectral radiance B(λ ₁ , T). Then, the calculation unit 4 substitutes the calculated black body spectral radiance B(λ ₁ , T) into the equation (2) to calculate the temperature T _est .

In the first embodiment, the calculation unit 4 repeatedly performs the operation of calculating the temperature T _est by the above-described method, assuming a certain temperature Tx, until the difference between the temperature Tx and the temperature T _est becomes the minimum. the difference between the temperature Tx and the temperature _{T est} is calculated as the temperature of the object 20 the temperature _{T est} when it becomes the minimum.

In addition, the calculation unit 4 calculates from the object 20 to the detectors 1 and 2 based on the transmittance τ(λ ₁ ) calculated by the above-described method and the distance 1 from the object 20 to the detectors 1 and 2. The absolute amount or concentration of absorber ABS present between the two is calculated.

FIG. 2 is a flowchart for explaining the detection method according to the first embodiment for detecting the temperature of the object 20 and/or the absolute amount or concentration of the absorber ABS.

With reference to FIG. 2, when the operation of detecting the temperature of the target object 20 and/or the absolute amount or concentration of the absorber ABS is started, the detectors 1 and 2 respectively detect the spectral irradiance I(λ ₁ , T). ), I(λ ₂ , T) is detected (step S1), and the detected spectral irradiance I(λ ₁ , T), I(λ ₂ , T) is output to the calculation unit 4.

The calculation unit 4 receives the spectral irradiances I(λ ₁ , T) and I(λ ₂ , T) from the detectors 1 and 2, respectively. Then, the calculation unit 4 sets the temperature T to a certain temperature Tx (step S2).

Then, the calculation unit 4 calculates the blackbody spectral radiances B(λ ₁ , T) and B(λ ₂ , T) corresponding to the temperature Tx based on the brightness table 41 (step S3).

Subsequently, the calculation unit 4 causes the spectral irradiances I(λ ₁ , T), I(λ ₂ , T), the emissivity ε(λ ₁ ), ε(λ ₂ ) and the blackbody spectral radiance B(λ ₁ , T) and B(λ ₂ , T) are substituted into the equation (3) to calculate the transmittance ratio τ(λ ₁ )/τ(λ ₂ ) (step S4).

The calculator 4, the ratio of the transmittance _{τ (λ 1) / τ (} λ 2) and extinction coefficient _{ε a (λ 1), ε} a (λ 2) calculated transmittance tau a (lambda ₁₎ on the basis of the Yes (step S5). More specifically, the calculation unit 4 detects the transmittance corresponding to the transmittance ratio τ(λ ₁ )/τ(λ ₂ ) based on the transmittance calculation table 42, thereby calculating the transmittance ratio. The transmittance τ(λ ₁ ) is calculated from τ(λ ₁ )/τ(λ ₂ ). Further, the calculation unit 4 substitutes the reciprocal of the transmittance ratio τ(λ ₁ )/τ(λ ₂ ) and the extinction coefficients ε _a (λ ₁ ), ε _a (λ ₂ ) into the equation (5) for transmission. Calculate the rate τ(λ ₁ ).

After step S5, the calculation unit 4 substitutes the detection ratio α, the spectral irradiance I(λ ₁ , T), the transmittance τ(λ ₁ ) and the emissivity ε(λ ₁ ) into the equation (1) to obtain black. Body spectral radiance B(λ ₁ , T) is calculated (step S6).

Then, the calculation unit 4 substitutes the calculated black body spectral radiance B(λ ₁ , T) into the equation (2) to calculate the temperature T _est (step S7).

Then, the calculation unit 4 calculates the difference ΔT between the temperature Tx and the temperature T _est (step S8), and determines whether or not the calculated difference ΔT is the minimum (step S9).

When it is determined in step S9 that the difference ΔT is not the minimum, the calculation unit 4 sets the temperature Tx to a different value (step S10). After that, the series of operations proceeds to step S3, and steps S3 to S10 are repeatedly executed until it is determined in step S9 that the difference ΔT is the minimum.

Then, when it is determined in step S9 that the difference ΔT is the minimum, the calculation unit 4 sets the temperature T _est when the difference Δ is the minimum as the temperature of the target object 20 (step S11). Then, the calculation unit 4 calculates the absolute amount or concentration of the absorber ABS based on the transmittance τ(λ ₁ ) when the difference Δ becomes the minimum (step S12). This completes a series of operations.

Equation (3), the ratio tau (lambda ₁₎ of the transmittance with respect to transmittance _{τ (λ 2) τ (λ} 1) / τ (λ 2) is a formula for calculating a relative transmittance tau (lambda ₁₎ The ratio τ(λ ₂ )/τ(λ ₁ ) of the transmittance τ(λ ₂ ) is calculated by the equation (1) for the spectral irradiance I(λ ₁ , T) and the spectral irradiance I(λ ₂ , T). It is derived from the equation (1) and the following equation.

Then, according to the equation (4) for the transmittance τ(λ ₁ ) and the equation (4) for the transmittance τ(λ ₂ ), the transmittance is calculated from the transmittance ratio τ(λ ₂ )/τ(λ ₁ ). The following equation for calculating the rate τ(λ ₂ ) is obtained.

Therefore, in the detection method shown in FIG. 2, the calculating unit 4 calculates the transmittance ratio τ(λ ₂ )/τ(λ ₁ ) by the equation (6) in step S4, and calculates it in step S5. The transmittance τ(λ ₂ ) may be calculated based on the transmittance ratio τ(λ ₂ )/τ(λ ₁ ). In this case, in step S6, the detection ratio α, the spectral irradiance I(λ ₂ , T), the transmittance τ(λ ₂ ) and the emissivity ε(λ ₂ ) are calculated with respect to the spectral irradiance I(λ ₂ , T). To calculate the black body spectral radiance B(λ ₂ , T), and in step S7, substitute the calculated black body spectral radiance B(λ ₂ , T) into the formula (2). Then, the temperature T _est can be calculated. In this case, in step S12, the calculation unit 4 calculates the absolute amount or concentration of the absorber ABS based on the transmittance τ(λ ₂ ) when the difference ΔT becomes the minimum. When calculating the transmittance τ(λ ₂ ) based on the transmittance ratio τ(λ ₂ )/τ(λ ₁ ), the calculator 4 calculates the transmittance ratio τ(λ ₂ )/τ(λ ₁ ) and the extinction coefficient ratio ε _a (λ ₁ )/ε _a (λ ₂ ) may be substituted into equation (7) to calculate the transmittance τ(λ ₂ ), or the transmittance ratio τ( Based on the transmittance calculation table including the relationship between λ ₂ )/τ(λ ₁ ) and the transmittance τ(λ ₂ ), the transmittance ratio τ(λ ₂ )/τ(λ ₁ ) to the transmittance τ(λ ₂ ) may be calculated.

In the first embodiment, the operation of detecting the temperature of object 20 and/or the absolute amount or concentration of absorber ABS may be executed by software. In this case, the calculation unit 4 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory).

The ROM receives the spectral irradiance I(λ ₁ , T) and the spectral irradiance I(λ ₂ , T) from the detectors 1 and 2, respectively, in step S1-1, and the emissivity via the input device (keyboard or the like). A program Prog_A including step S1-2 for receiving ε(λ ₁ ), ε(λ ₂ ) and extinction coefficients ε _a (λ ₁ ), ε _a (λ ₂ ) and steps S2 to S12 shown in FIG. Store. The ROM also stores the brightness table 41 and the transmittance calculation table 42 shown in FIG. The RAM receives the spectral irradiance I(λ ₁ , T), the spectral irradiance I(λ ₂ , T), the emissivity ε(λ ₁ ), ε(λ ₂ ) and the extinction coefficient ε _a (λ) received by the CPU. ₁ ), ε _a (λ ₂ ), the blackbody spectral radiance B(λ ₁ , T), B(λ ₂ , T) calculated by the CPU, and the transmittance ratio τ(λ ₁ ) calculated by the CPU. /Τ(λ ₂ ), the transmittance τ(λ ₁ ) calculated by the CPU, the temperature T _est calculated by the CPU, and the calculated difference ΔT are temporarily stored.

The CPU reads the program Prog_A from the ROM, sequentially executes steps S1-1, S1-2, S2 to S12 of the read program Prog_A, and the temperature of the object 20 and/or the absorber ABS is measured by the method described above. To detect the absolute amount or concentration of.

In this case, the black body spectral radiance B(λ ₁ , T), B(λ ₂ , T), the transmittance ratio τ(λ ₁ )/τ(λ ₂ ), the transmittance τ(λ ₁ ), the temperature T _The CPU that calculates _est and the difference ΔT constitutes “calculation means”. Further, the spectral irradiance I(λ ₁ , T), the spectral irradiance I(λ ₂ , T), the emissivity ε(λ ₁ ), ε(λ ₂ ) and the extinction coefficient ε _a (λ ₁ ), ε _a ( The CPU that accepts λ ₂ ) constitutes “accepting means”.

Further, the program Prog_A may be recorded in a recording medium (for example, CD and DVD) and distributed. In this case, the computer (CPU) reads the program Prog_A from the recording medium and executes it to detect the temperature of the object 20 and/or the absolute amount or concentration of the absorber ABS. Therefore, a CD, a DVD, or the like in which the program Prog_A is recorded is a computer (CPU) readable recording medium in which the program Prog_A is recorded.

As described above, in the first embodiment, the spectral irradiance I(λ ₁ , T), I(λ ₂ , T) detected by the detectors ₁ and ₂ , the known emissivity ε(λ ₁ ), ε(λ ₂ ), known extinction coefficients ε _a (λ ₁ ), ε _a (λ ₂ ), and black body spectral radiance B(λ ₁ , T), B(λ ₂ ) calculated from the luminance table 41. , T). The detection method according to the first embodiment uses the above-mentioned parameters to calculate _{one of the} transmittance τ(λ ₁ ) and the transmittance τ(λ ₂ ) and calculates the calculated transmittance (transmittance τ(λ ₁ ) and the transmittance τ(λ ₂ ) whichever is required) as long as the temperature of the object 20 and/or the absolute amount or concentration of the absorber ABS is calculated.

In this way, the infrared detection device 10 functions as a radiation thermometer that calculates the temperature of the object 20 and/or a gas sensor that calculates the absolute amount or concentration of the absorber ABS.

In the infrared detection device 10, the detection ratio α and the extinction coefficient ratio ε _a (λ ₂ )/ε _a (λ ₁ ) (or the extinction coefficient ratio ε _a (λ ₁ )/ε _a (λ ₂ )) are It is preset in the infrared detection device 10.

For simplicity, the detection rate α is 0.1 and the emissivity ε(λ ₁ ) is 1. Moreover, the temperature of the target object 20 is set to 0 to 100°C.

The brightness table 41 and the transmittance calculation table 42 are set in advance in the infrared detection device 10 as follows.

FIG. 3 is a diagram showing the relationship between the transmittance and the wavelength. In FIG. 3, the vertical axis represents the transmittance and the horizontal axis represents the wavelength.

Referring to FIG. 3, water (H ₂ O), oxygen (O ₂ ), ozone (O ₃ ), and carbon dioxide (CO ₂ ) are shown in association with absorption wavelengths as absorption molecules existing in the atmosphere. ing.

As shown in FIG. 3, within the range of the atmospheric window, for example, the wavelength λ ₁ is set to 8.5 μm and the wavelength λ ₂ is set to 13.0 μm.

In the brightness table 41, the relationship between the temperature and the black body spectral radiance at wavelengths of 8.5 μm and 13.0 μm is set. Further, referring to FIG. 3, the extinction coefficient ratio ε _a (λ ₂ )/ε _a (λ ₁ ) is set to, for example, 0.37, and the set extinction coefficient ratio ε _a (λ ₂ )/ The relationship between the transmittance ratio and the transmittance is set in the transmittance calculation table 42 by using ε _a (λ ₁ )=0.37. The extinction coefficient ratio ε _a (λ ₂ )/ε _a (λ ₁ )=0.37 is the ratio of the extinction coefficients of water vapor at wavelengths of 8.5 μm and 13.0 μm.

[Temperature calculation accuracy]
The calculation accuracy of the temperature in the first embodiment will be described based on the simulation. First, we created a simulation task. Set the transmittances τ(λ ₁ )=0.77 and τ(λ ₂ )=0.50 that match the adopted extinction coefficient ratio of 0.37, and respond to each temperature based on equation (1). Spectral irradiance I (8.5 μm, T) and I (13.0 μm, T) were calculated. This spectral irradiance was defined as the spectral irradiance detected by the detectors 1 and 2, and the temperature T _est of the target object 20 was calculated by the detection method shown in FIG.

Then, the temperature was calculated based on the equation (1) regarding the detector 1, the brightness table 41, and the transmittance calculation table 42.

FIG. 4 is a diagram showing a temperature difference between the set temperature of the target object 20 and the calculated temperature obtained by the simulation. In FIG. 4, the vertical axis represents the difference between the calculated temperature and the temperature of the target object 20, and the horizontal axis represents the temperature of the target object 20.

With reference to FIG. 4, even when the transmittance depends on the wavelength, the calculated temperature falls within an error of about +0.3° C. to +0.5° C. with respect to the temperature of the object 20. Therefore, it was found that the temperature of the object 20 can be calculated with high accuracy in the presence of the absorber ABS.

[Effects of First Embodiment]
(Effects of radiation thermometer)
The effect of using the infrared detection device 10 as a radiation thermometer will be described.

In the conventional single-color method, the transmittance is set to a value predicted in advance to calculate the temperature of the object 20, and therefore, if the transmittance is different from the predicted value, a calculation error occurs in temperature. For example, assuming a monochromatic radiation thermometer that detects infrared rays having a wavelength of 8.5 μm, it is assumed that the place where the transmittance should be set to 0.77 is set to 1.0. That is, the radiation thermometer estimates the spectral radiance of the object 20 to be 0.77 times the original value.

Under this condition, if the temperature of the object 20 at 35° C. is calculated by the equation (1), the calculated temperature will be about 21° C., which causes a large calculation error.

Further, in the conventional two-color method, the temperature cannot be calculated with high accuracy because the transmittance has wavelength dependency. In the conventional two-color method, the temperature of the object 20 is calculated on the assumption that the transmittance does not depend on the wavelength. Therefore, if the actual transmittance depends on the wavelength, a calculation error occurs in the temperature. For example, using a conventional two-color radiation thermometer that detects infrared rays having a wavelength of 8.5 μm and infrared rays having a wavelength of 13.0 μm, the transmittances are τ(8.5 μm)=0.77 and τ(13 .0)=0.5, the case where the temperature of the target object 20 is calculated is assumed.

Under this condition, if the temperature is calculated by regarding the ratio of the spectral irradiance as the ratio of Planck's equation, the temperature of the object 20 at 35° C. is calculated as 137° C. On the other hand, as shown in the simulation and FIG. 4, the radiation thermometer (infrared detection device 10) according to the first embodiment can accurately calculate the temperature even when the transmittance depends on the wavelength. That is, the radiation thermometer (infrared ray detection device 10) has a transmittance correction function not found in conventional radiation thermometers.

According to the first embodiment, the temperature of the object 20 can be calculated by correcting the transmittance using the two detectors 1 and 2 that detect infrared rays having an arbitrary wavelength. As a result, for example, in an environment in which the transmittance greatly changes due to the influence of water vapor or the like (for example, outdoors in bad weather such as rain and fog, a bathroom, etc.), the detection performance of humans or animals can be improved. That is, in bad weather, a person or an animal can be detected from a longer distance, and an accident in a bathroom can be found earlier.

Further, according to the infrared detection device 10, the temperature can be calculated with high accuracy by using the wavelengths λ ₁ and λ ₂ whose transmittance can be reduced due to the presence of the absorber ABS such as water vapor. For example, it is possible to use, as the detection wavelengths λ ₁ and λ ₂ , those outside the range of the atmospheric window, which has been conventionally unsuitable. That is, even when the detection wavelengths λ ₁ and λ ₂ belong to the range of 3 to 3.5 μm, 4.5 to 8 μm, or 13 to 16 μm, the temperature T _est and the transmittance τ(λ ₁ ) (or the transmittance τ(λ ₂ )) can be calculated with high accuracy.

Since the absorber ABS existing between the object 20 and the infrared detection device 10 is determined by the wavelengths λ ₁ and λ ₂ , it is necessary to inspect the type of the absorber ABS in advance, especially in the atmosphere. There is no.

(Effects on gas sensor)
The effect of using the infrared detection device 10 as a gas sensor will be described. The infrared detection device 10 can calculate the transmittance of the absorber ABS and at the same time calculate the absolute amount of the absorber ABS. When the distance 1 between the object 20 and the infrared detection device 10 is known, the concentration of the absorber ABS can be calculated. For example, if the absorber ABS is water vapor, the amount of water vapor and the humidity at the distance 1 between the object 20 and the infrared detection device 10 can be calculated. The target absorber ABS is not limited to water vapor, but may be a gas absorber such as carbon dioxide or a scatterer such as an aerosol.

According to the infrared detection device 10, as long as the temperature of the target object 20 is within a certain range, the concentration of the absorber ABS can be calculated with high accuracy. That is, for example, as compared with a gas sensor using an infrared detector represented by Patent Document 3, the infrared detection device 10 does not require a light source as a constituent element. Therefore, in a situation where it is difficult to install a light source or a situation where it is desired to suppress energy consumption, calculation of the gas concentration of the infrared detection device 10 is very effective. That is, since it can be used as a space-saving and energy-saving gas sensor, it can be used as an IoT (Internet of things) device in which a large number of sensors need to be arranged.

Since the absorber ABS existing between the object 20 and the infrared detection device 10 is determined by the wavelengths λ ₁ and λ ₂ , the type of the absorber ABS is inspected in advance, especially in the atmosphere. No need.

The distance 1 between the object 20 and the infrared detection device 10 may be measured in advance if the object 20 and the infrared detection device 10 are fixed. When the infrared detection device 10 is provided with a lens, the focal length of the lens may be the distance 1 between the object 20 and the infrared detection device 10.
(Effects of radiation thermometer and gas sensor)
The effect when the infrared detection device 10 is used as a detection device having both functions of a radiation thermometer and a gas sensor will be described.

Which gas species the infrared detection device 10 detects depends on whether or not it has absorption at the detection wavelengths λ ₁ and λ ₂ . For example, with water vapor, the humidity can be calculated while measuring the temperature of the object 20 regardless of whether it is indoors or outdoors. In Patent Document 2, a hygrometer is provided, but this hygrometer measures the humidity in the vicinity of the radiation thermometer.

On the other hand, the infrared detection device 10 measures the average humidity from the object 20 to the detectors 1 and 2. Therefore, in a situation where the environment between the object 20 and the detectors 1 and 2 is greatly different, the calculation of temperature and humidity by the infrared detection device 10 is very effective. That is, since the cooking appliance in which water vapor is retained can be used for detecting the temperature and the amount of water vapor, the user or the cooking appliance itself can judge the cooking state and provide feedback.

For example, if the gas type to be detected is carbon dioxide, the carbon dioxide concentration can be calculated while measuring the temperature of the object regardless of whether it is indoors or outdoors. Patent Document 4 is a gas sensor that detects the carbon dioxide concentration, and this gas sensor measures the carbon dioxide concentration near the installation location.

On the other hand, the infrared detection device 10 measures the average carbon dioxide concentration from the object 20 to the detectors 1 and 2. Therefore, in a situation where the environment between the object 20 and the detectors 1 and 2 is greatly different, the calculation of the temperature and the carbon dioxide concentration by the infrared detection device 10 is very effective. That is, in the ventilation equipment/air conditioning equipment for adjusting the carbon dioxide concentration, it is possible to use the infrared detection device 10 for detecting the indoor/outdoor carbon dioxide concentration. The state of carbon concentration can be judged and fed back.

If the target to be detected is not an absorber such as gas but a scatterer such as aerosol, the concentration of the scatterer can be calculated while measuring the temperature of the target. That is, since it can be used for detection of scatterers in ventilation equipment, air conditioning equipment and air purifiers, the user or the ventilation equipment, air conditioning equipment and air purifier itself determine the state of scatterer concentration. , You can give feedback.
(Effects of radiation thermometer and gas sensor for measuring substantial temperature)
In the following, the substantial temperature around the object 20 is simply referred to as “substantial temperature”.

Since the infrared detection device 10 can detect the temperature and the concentration of the absorber at the same time, it is suitable for a device that measures a substantial temperature calculated from the temperature of the object 20 and the concentration of the absorber ABS and the comfort index. For example, by detecting the temperature and the humidity at the same time, the substantial temperature calculated from the temperature and the humidity can be measured. The substantial temperature includes, for example, a sensible temperature, which is a temperature felt by a person, and an effective heating temperature applied to food by a cooking device. Generally, as the temperature and humidity of the object 20 increase, the substantial temperature rises.

A suitable wavelength for calculating the substantial temperature will be described. As described above, in the first embodiment, the relational expression of the ratio of the spectral irradiance of the formula (1), the ratio of the black body spectral radiance determined by the temperature of the object 20, and the ratio of the transmittance determined by the transmittance. Then, the temperature and the transmittance of the object 20 are calculated in accordance with. That is, when a calculation error occurs in the division of the black body spectral radiance ratio and the transmittance ratio, a calculation error may occur in the temperature and the transmittance of the object 20.

On the other hand, it is possible to calculate the substantial temperature with high accuracy even when an error is involved in the division of the ratio of the temperature of the object 20 to the transmittance. For example, regardless of whether the value of temperature or humidity is increased, under the condition that the ratio of the spectral irradiance increases, the calculation error due to the carving can be canceled out, so that the actual temperature must be calculated with high accuracy. You can That is, since the temperature and humidity are not sufficiently separated due to an experimental error and an error in the transmission model, and even if the temperature is calculated to be lower (higher) than the actual temperature, the humidity is calculated to be higher (lower), and thus the actual temperature is calculated. The error is small. In other words, the substantial temperature can be calculated with high accuracy by selecting the wavelengths λ ₁ and λ ₂ so that the correlation between the substantial temperature and the ratio of the spectral irradiance becomes large.

When the detection wavelengths λ ₁ and λ ₂ are set to λ ₁ <λ ₂ according to the first embodiment, when the temperature of the object 20 rises, due to the nature of Planck's equation, the black body spectroscopy of the detection wavelengths λ ₁ and λ ₂ is performed. The radiance ratio (B(λ ₁ , T)/B(λ ₂ , T)) increases. In other words, when the temperature of the object 20 increases, the ratio of the spectral irradiance of the detectors 1 and 2 (I(λ ₁ , T)/I(λ ₂ , T)) increases.

Therefore, if the wavelengths λ ₁ and λ _{2 in} which the transmittance ratio (τ(λ ₁ )/τ(λ ₂ )) increases with an increase in humidity are selected, the spectral irradiance I(λ ₁ , T) and the spectral irradiance I(λ ₂ , T) of the detector 2 (I(λ ₁ , T)/I(λ ₂ , T)) is also increased, which is caused by the error in separating temperature and humidity. Substantial temperature calculation error is reduced.

FIG. 5 is a diagram showing the relationship between the transmittance of water vapor and the wavelength. In FIG. 5, the vertical axis represents water vapor transmission rate at a certain humidity, and the horizontal axis represents wavelength.

Referring to FIG. 5, in the wavelength region of 3.0 to 16 μm, the water vapor transmission rate can be classified into three types: a high transmission rate region, a first low transmission rate region, and a second low transmission rate region. The high transmittance region is a wavelength region showing a high transmittance of 3.5 to 4.5 μm and 8.0 to 13.0 μm. The first low transmittance region is a low transmittance region of 3.0 to 3.5 μm and 6.0 to 8.0 μm and a wavelength region where the transmittance increases as the wavelength becomes longer. The second low transmittance region is a low transmittance region of 4.5 to 6.0 μm and 13.0 to 16.0 μm and a wavelength region where the transmittance decreases as the wavelength becomes longer.

According to the Lambert-Beer law shown in the equation (4), there is a negative correlation between the transmittance and the extinction coefficient at the same absorber concentration. That is, the wavelength condition in which the transmittance ratio (τ(λ ₁ )/τ(λ ₂ )) increases with an increase in humidity satisfies τ(λ ₁ )>τ(λ ₂ ) in FIG. Wavelength. That is, when the detection wavelength λ ₁ belongs to the high transmittance region and the detection wavelength λ ₂ belongs to the first low transmittance region or the second low transmittance region, and the detection wavelengths λ ₁ and λ ₂ are the same. This is the case of belonging to the second low transmittance region.

That is, when the detection wavelength λ ₁ is in the range of 3.5 to 4.5 μm, and the detection wavelength λ ₂ is in the range of 4.5 to 8.0 μm and 13.0 to 16.0 μm, it is possible to achieve high accuracy. Temperature can be calculated. Or detection wavelength lambda ₁ in a range of 8.0～13.0Myuemu, and, if the detection wavelength lambda ₂ within the scope of 13.0～16.0Myuemu, detection wavelength lambda ₁ and the detection wavelength lambda ₂ is 4.5 to When it belongs to the range of 6.0 μm, the substantial temperature can be calculated with high accuracy. Alternatively, when the detection wavelength λ ₁ and the detection wavelength λ ₂ belong to the range of 13.0 to 16.0 μm, the substantial temperature can be calculated with high accuracy.

Regarding the calculation of the substantial temperature, instead of the brightness table 41 and the transmittance calculation table 42, a calculation parameter for directly calculating the substantial temperature from the spectral irradiance of the detection wavelength λ ₁ and the detection wavelength λ ₂ is calculated. You may arrange|position in the part 4.
(Effects of radiation thermometer and gas sensor for measuring comfort index)
The comfort index may be calculated based on the temperature and the carbon dioxide concentration, or the temperature and the aerosol concentration, instead of the actual temperature. Thus, the user, the cooking device, the ventilation device, the air conditioning device, and the air purifier can perform feed back by making a judgment based on the substantial temperature and the index of comfort.

With respect to the comfort index that decreases when the temperature and the carbon dioxide concentration increase, a suitable wavelength will be described. Similar to the case of the substantial temperature, the condition that can reduce the error in separating the temperature of the object 20 from the transmittance is that the ratio of the transmittance (τ(λ ₁ )/τ( There are two detection wavelengths that increase λ ₂ )).

FIG. 6 is a diagram showing the relationship between the transmittance of carbon dioxide at a certain humidity and the wavelength. Referring to FIG. 6, in the case of the carbon dioxide transmittance, the wavelength range of 3.0 to 16 μm is set in three types: a high transmittance area, a second low transmittance area, and a third low transmittance area. Can be classified into The high transmittance region is a wavelength region showing a high transmittance of 3.5 to 4.0 μm and 4.5 to 13.5 μm. The second low transmittance region is a low transmittance region of 13.5-16.0 μm and a wavelength region in which the transmittance decreases as the wavelength becomes longer. The third low transmittance region is a wavelength region showing a low transmittance of 4.0 to 4.5 μm.

According to the Lambert-Beer law shown in the equation (4), there is a negative correlation between the transmittance and the extinction coefficient at the same absorber concentration. That is, the wavelength condition in which the transmittance ratio (τ(λ ₁ )/τ(λ ₂ )) increases with an increase in humidity satisfies τ(λ ₁ )>τ(λ ₂ ) in FIG. Wavelength. More specifically, when the detection wavelength λ ₁ belongs to the high transmittance region and the detection wavelength λ ₂ belongs to the second low transmittance region or the second low transmittance region, and the detection wavelength λ ₁ and This is the case where the detection wavelength λ ₂ belongs to the same second low transmittance region.

That is, when the detection wavelength λ ₁ is in the range of 3.5 to 4.0 μm, and the detection wavelength λ ₂ is in the range of 4.0 to 4.5 μm and 13.5-16.0 μm, the comfort with high accuracy is achieved. A sex index can be calculated. Alternatively, when the detection wavelength λ ₁ belongs to the range of 4.5 to 13.5 μm and the detection wavelength λ ₂ belongs to the range of 13.5 to 16.0 μm, the comfort index can be calculated with high accuracy. .. Alternatively, when the detection wavelength λ ₁ and the detection wavelength λ ₂ belong to the range of 13.5 to 16.0 μm, the comfort index can be calculated with high accuracy.

Regarding the calculation of the comfort index, instead of the brightness table 41 and the transmittance calculation table 42, a calculation parameter for directly calculating the comfort index from the spectral irradiance of the detection wavelength λ ₁ and the detection wavelength λ ₂ is calculated. You may arrange|position in the part 4.
(Effects of Application of First Embodiment)
In the first embodiment, the emissivity needs to be known, but since it is known that the object 20 is a person, an animal, a cooking utensil, a cooking utensil, etc., it is sufficient to enter the value. ..

Further, by forming the infrared detection device 10 according to the first embodiment into an array, it can be used as an infrared camera. The infrared camera to which the first embodiment is applied can simultaneously capture both an image regarding the temperature of the target object 20 and an image regarding the absolute amount of the absorber. With this function, the contour and distribution of the object 20 can be determined with higher accuracy.

[Second Embodiment]
FIG. 7 is a schematic diagram of an infrared detection device according to the second embodiment. With reference to FIG. 7, an infrared detection device 10A according to the second embodiment has a configuration in which the detector 1 of the infrared detection device 10 shown in FIG. 1 is replaced by a detector 3 and the calculation unit 4 is replaced by a calculation unit 4A. The others are the same as the infrared detection device 10.

The detector 3 detects the spectral irradiance I(λ ₃ , T) of the infrared IFR3 having the wavelength λ ₃ (>λ ₂ ) and sends the detected spectral irradiance I(λ ₃ , T) to the calculation unit 4A. Output.

In the second embodiment, if the wavelengths λ ₂ and λ ₃ are longer than the peak wavelength at which the maximum value of the black body spectral radiance is obtained, the temperature can be calculated with higher accuracy for the reason described later.

The detector 3 uses a detector that performs photoelectric conversion with an InGaAs bandgap, a detector that has a wavelength filter mounted on a thermal detector such as a bolometer, and uses energy levels of quantum dots stacked in multiple layers. It comprises a quantum dot detector for photoelectric conversion, a quantum well detector for photoelectric conversion utilizing the energy levels of quantum wells laminated in multiple layers, and the like.

The detectors 2 and 3 may be the same or different from each other. If the detectors 2, 3 are the same, that is, the two detectors 2, 3 are constituted by one detector, the detectors 2, 3 may be quantum dot detectors or quantum well detectors. Become. The quantum dot detector or the quantum well detector can control the detection wavelength according to the applied voltage. As a result, only one detector is required, so that the infrared detector 10A can be downsized and the cost can be reduced. When the two detectors 2 and 3 are configured by one detector, the infrared detection device 10A detects the voltage V ₂ for setting the wavelength to be detected to the wavelength λ ₂ (a quantum dot type detector or a quantum dot type detector). Control unit for applying the voltage V ₃ for setting the wavelength to be detected to the wavelength λ ₃ to the detector (comprising a quantum dot detector or a quantum well detector) Is further provided.

The calculation unit 4A further includes a wavelength selection unit 44 in the calculation unit 4 illustrated in FIG. 1, and includes a brightness ratio parameter 43 instead of the brightness table 41. The luminance ratio parameter 43 is composed of an approximate value R _est of the ratio of the black body spectral radiance. The wavelength selection unit 44 selects the wavelengths λ ₂ and λ ₃ based on the accuracy rating of the radiation thermometer and the measurement range of the temperature of the object 20 by the method described later.

In the second embodiment, the transmittance calculation table 42 includes the relationship between the transmittance ratio τ(λ ₂ )/τ(λ ₃ ) and the transmittance τ(λ ₂ ). Further, the emissivity ε(λ ₂ ), ε(λ ₃ ) and the extinction coefficients ε _a (λ ₂ ), ε _a (λ ₃ ) are assumed to be known.

FIG. 8 is a diagram showing the relationship between the spectral radiance and the wavelength. In FIG. 8, the vertical axis represents the spectral radiance and the horizontal axis represents the wavelength.

Referring to FIG. 8, the wavelength dependence of the spectral radiance is represented by Expression (2) (Planck's expression). The relationship between the peak wavelength λ _max that gives the maximum value of the spectral radiance and the temperature T is generally known as the Wien's displacement law expressed by the following equation.

In the formula (8), b is 2900 [K·μm].

The conditions for calculating the transmittance and the temperature of the object 20 using the _two detection wavelengths λ ₂ and λ ₃ will be described.

Condition 1) the extinction coefficient of the absorption coefficient of the detection wavelength λ ₂ ε _a (λ ₂₎ is the detection wavelength λ ₃ ε _a (λ ₃₎ differ.

When the extinction coefficient ε _a (λ ₂ ) is the same as the extinction coefficient ε _a (λ ₃ ), for example, the transmittance τ(λ ₂ ) is calculated by the equation (5) for the _two detection wavelengths λ ₂ and λ _3. Condition 1 is necessary because it cannot be calculated.

Condition 2) The two detection wavelengths λ ₂ and λ ₃ are long wavelengths. For example, the two detection wavelengths λ ₂ and λ ₃ are long wavelengths with respect to the wavelength λ _{max at} which the spectral radiance of the object 20 has a peak value.

Condition 3) The wavelength difference between the _two detection wavelengths λ ₂ and λ ₃ is less than or equal to the threshold value Δλ _th . The threshold value Δλ _th is, for example, 2 μm.

Then, in the second embodiment, the following three combinations can be used as the combination of Condition 1 to Condition 3.

(I) Combination of conditions 1 to 3 (II) Combination of conditions 1 and 2 (III) Combination of conditions 1 and 3 When the wavelengths λ ₂ and λ ₃ satisfy the above condition 2, black body spectroscopy The ratio of the radiance B(λ ₂ , T) and the black body spectral radiance B(λ ₃ , T) is represented by the following equation, and the temperature dependence is reduced.

As the detection wavelength λ ₂ and the detection wavelength λ ₃ are longer, the blackbody spectral radiance approaches the Rayleigh-Jean's law, and the temperature dependence of the ratio of the blackbody spectral radiance decreases.

In particular, when the detection wavelength λ ₂ and the detection wavelength λ ₃ are long wavelengths with respect to the wavelength λ _{max at} which the spectral radiance of the object 20 has a peak value, the blackbody spectral radiance is according to Rayleigh-Jean's law. , The ratio of the blackbody spectral radiance becomes independent of temperature. In this case, the black body spectral radiance ratio is expressed by the following equation.

When the wavelength difference between the _two detection wavelengths λ ₂ and λ ₃ is less than or equal to the threshold value Δλ _th , the black body spectral radiance B(λ ₂ , T) and the black body spectral radiance B(λ ₃ , T) are It is almost equal. That is, the following equation is established.

The inventor has found that when the two wavelengths λ ₂ and λ ₃ satisfy the above condition 2 or condition 3, the temperature dependence of the black body spectral radiance ratio B(λ ₃ ,T)/B(λ ₂ ,T). Was found to be smaller than a certain value. Therefore, in the second embodiment, the temperature of the object 20 is calculated by using the fact that the temperature dependence of the ratio of the black body spectral radiance is small.

In this case, the combinations shown in (I) to (III) above are used. Then, when the combination of the above (I) is used, the temperature of the object 20 can be calculated most accurately.

As for the spectral irradiance I(λ ₃ , T), the above-mentioned formula (1) is established. Therefore, the formula (1) for the spectral irradiance I(λ ₂ , T) and the spectral irradiance I(λ ₃ , T) are used. The following equation is obtained from the equation (1) for () and the equation (9).

Formula (12) is the ratio of spectral irradiance I(λ ₂ , T)/I(λ ₃ , T), the ratio of emissivity ε(λ ₃ )/ε(λ ₂ ) and the ratio of blackbody spectral radiance. It means that the ratio of transmittance τ(λ ₂ , T)/τ(λ ₃ , T) can be calculated by R.

In the second embodiment, the black body spectral radiance ratio R is set as the brightness ratio parameter 43 to the approximate value R _est of the black body spectral radiance ratio. That is, the brightness ratio parameter 43 is composed of the approximate value R _est .

The calculating unit 4A calculates the transmittance ratio τ(λ ₂ )/τ(λ ₃ ) by the equation (12). The calculation unit 4A is calculated ratio of the transmittance _{τ (λ 2) / τ (} λ 3) to apply the formula (5) is calculated transmittance tau a (lambda _2).

Then, the calculation unit 4A calculates the detection ratio α, the calculated transmittance τ(λ ₂ ), the spectral irradiance I(λ ₂ , T) detected by the detector 2 and the known emissivity ε(λ ₂ ) as The black body spectral radiance B(λ ₂ , T) is calculated by substituting it into the equation (1) for the spectral irradiance I(λ ₂ , T), and the calculated black body spectral radiance B(λ ₂ , T). ) Is substituted into the equation (2) to calculate the temperature T _{est of the} object 20. Here, the detection ratio α is preset in the calculation unit 4A as in the first embodiment.

Further, the calculation unit 4A calculates the absolute amount or concentration of the absorber ABS based on the transmittance τ(λ ₂ ) in the same manner as the calculation unit 4.

FIG. 9 is a flowchart for explaining the detection method according to the second embodiment for detecting the temperature of the object 20 and/or the absolute amount or concentration of the absorber ABS.

With reference to FIG. 9, when the operation of detecting the temperature of the target object 20 and/or the absolute amount or concentration of the absorber ABS is started, the detectors 2 and 3 respectively detect the spectral irradiance I(λ ₂ , T). ), I(λ ₃ , T) is detected (step S21), and the detected spectral irradiance I(λ ₂ , T), I(λ ₃ , T) is output to the calculation unit 4A.

The calculation unit 4A receives the spectral irradiances I(λ ₂ , T) and I(λ ₃ , T) from the detectors 2 and 3, respectively.

Then, the calculation unit 4A detects the approximate value R _est of the ratio of the black body spectral radiance from the brightness ratio parameter 43 (step S22).

After that, the calculation unit 4A approximates the ratio of the spectral irradiances I(λ ₂ , T), I(λ ₃ , T), the emissivity ε(λ ₂ ), ε(λ ₃ ) and the blackbody spectral radiance. R _est is substituted into the equation (12) to calculate the transmittance ratio τ(λ ₂ )/τ(λ ₃ ) (step S23).

Subsequently, the calculation unit 4A is, the ratio of the transmittance _{τ (λ 2) / τ (} λ 3) and extinction coefficient _{ε a (λ 2), ε} a (λ 3) transmittance tau based on the (lambda ₂₎ Calculate (step S24). More specifically, the calculator 4A detects the transmittance ratio τ by detecting the transmittance corresponding to the transmittance ratio τ(λ ₂ )/τ(λ ₃ ) based on the transmittance calculation table 42. The transmittance τ(λ ₂ ) is calculated from (λ ₂ )/τ(λ ₃ ). Further, the calculation unit 4A substitutes the reciprocal of the transmittance ratio τ(λ ₂ )/τ(λ ₃ ) and the extinction coefficients ε _a (λ ₂ ), ε _a (λ ₃ ) into the equation (5) for transmission. Calculate the rate τ(λ ₂ ).

After step S24, the calculation unit 4A substitutes the detection ratio α, the spectral irradiance I(λ ₂ , T), the transmittance τ(λ ₂ ) and the emissivity ε(λ ₂ ) into the formula (1) to obtain black. The body spectral radiance B(λ ₂ , T) is calculated (step S25).

Then, the calculation unit 4A substitutes the calculated black body spectral radiance B(λ ₂ , T) into the equation (2) to calculate the temperature T _est (step S26).

Subsequently, the calculation unit 4A calculates the absolute amount or concentration of the absorber ABS based on the transmittance τ(λ ₂ ) (step S27). This completes a series of operations.

Equation (12), the ratio tau (lambda ₂₎ of the transmittance with respect to transmittance _{τ (λ 3) τ (λ} 2) / τ (λ 3) is a formula for calculating a relative transmittance tau (lambda ₂₎ The ratio τ(λ ₃ )/τ(λ ₂ ) of the transmittance τ(λ ₃ ) is calculated by the formula (1) for the spectral irradiance I(λ ₂ ,T) and the spectral irradiance I(λ ₃ ,T). It is derived from the equation (1) and the following equation.

Then, using the formula (4) for the transmittance τ(λ ₂ ) and the formula (4) for the transmittance τ(λ ₃ ), the transmittance is calculated from the ratio τ(λ ₃ )/τ(λ ₂ ). The following equation for calculating the rate τ(λ ₃ ) is obtained.

Therefore, in the detection method shown in FIG. 9, the calculation unit 4A calculates the transmittance ratio τ(λ ₃ )/τ(λ ₂ ) by the equation (13) in step S23, and the equation (13) in step S24. 14), the transmittance τ(λ ₃ ) may be calculated based on the calculated transmittance ratio τ(λ ₃ )/τ(λ ₂ ). In this case, in step S25, the detection ratio α, the spectral irradiance I(λ ₃ , T), the transmittance τ(λ ₃ ) and the emissivity ε(λ ₃ ) are calculated with respect to the spectral irradiance I(λ ₃ , T). To calculate the black body spectral radiance B(λ ₃ , T), and in step S26, substitute the calculated black body spectral radiance B(λ ₃ ,T) into the formula (2). Then, the temperature T _est can be calculated. In this case, the calculation unit 4A calculates the absolute amount or concentration of the absorber ABS based on the transmittance τ(λ ₃ ) in step S27. When calculating the transmittance τ(λ ₃ ) based on the transmittance ratio τ(λ ₃ )/τ(λ ₂ ), the calculation unit 4A uses the transmittance ratio τ(λ ₃ )/τ(λ ₂ ) and the extinction coefficient ratio ε _a (λ ₂ )/ε _a (λ ₃ ) may be substituted into equation (14) to calculate the transmittance τ(λ ₃ ), or the transmittance ratio τ( Based on the transmittance calculation table including the relationship between λ ₃ )/τ(λ ₂ ) and the transmittance τ(λ ₃ ), the transmittance ratio τ(λ ₃ )/τ(λ ₂ ) to the transmittance τ(λ ₃ ) may be calculated.

In the second embodiment, the operation of detecting the temperature of the object 20 and/or the absolute amount or concentration of the absorber ABS may be executed by software. In this case, the calculation unit 4A includes a CPU, ROM and RAM.

The ROM receives the spectral irradiance I(λ ₂ , T) and the spectral irradiance I(λ ₃ , T) from the detectors 2 and 3, respectively, at step S1-1A, and the emissivity via the input device (keyboard or the like). A program Prog_B including step S1-2A for receiving ε(λ ₂ ), ε(λ ₃ ) and extinction coefficients ε _a (λ ₂ ), ε _a (λ ₃ ), and steps S22 to S27 shown in FIG. 9. Store. The ROM also stores the transmittance calculation table 42 and the brightness ratio parameter 43 shown in FIG. 7. The RAM has the spectral irradiances I(λ ₂ , T), I(λ ₃ , T), emissivity ε(λ ₂ ), ε(λ ₃ ) and extinction coefficient ε _a (λ ₂ ), which are received by the CPU. ε _a (λ ₃ ), the approximate value R _est of the ratio of the black body spectral radiance detected by the CPU, the transmittance ratio τ(λ ₂ )/τ(λ ₃ ) calculated by the CPU, and the calculation The transmittance τ(λ ₂ ) and the temperature T _est calculated by the CPU are temporarily stored.

The CPU reads the program Prog_B from the ROM, sequentially executes steps S1-1A, S1-2A, and S22 to S27 of the read program Prog_B, and the temperature of the object 20 and/or the absorber ABS is measured by the method described above. To detect the absolute amount or concentration of.

In this case, the CPU that detects the approximate value R _est of the black body spectral radiance ratio constitutes a “detection unit”, and the transmittance ratio τ(λ ₂ )/τ(λ ₃ ), the transmittance τ(λ ₂ ) and the CPU that calculates the temperature T _est form “calculation means”. Further, spectral irradiances I(λ ₂ , T), I(λ ₃ , T), emissivity ε(λ ₂ ), ε(λ ₃ ) and extinction coefficients ε _a (λ ₂ ), ε _a (λ ₃ ) The CPU that accepts "constitutes" constitutes "accepting means".

Further, the program Prog_B may be recorded in a recording medium (for example, CD and DVD) and distributed. In this case, the computer (CPU) reads the program Prog_B from the recording medium and executes it to detect the temperature of the object 20 and/or the absolute amount or concentration of the absorber ABS. Therefore, a CD, a DVD, or the like having the program Prog_B recorded therein is a computer (CPU) readable recording medium having the program Prog_B recorded therein.

As described above, in the second embodiment, the spectral irradiances I(λ ₂ , T), I(λ ₃ , T) detected by the detectors ₂ , ₃ and the known emissivity ε(λ ₂ ), Approximate value R _est of the ratio of the black body spectral radiance detected from ε(λ ₃ ), known extinction coefficients ε _a (λ ₂ ), ε _a (λ ₃ ), and the luminance ratio parameter 43 is used. The detection method according to the second embodiment uses the parameters described above to calculate one of the transmittance τ(λ ₂ ) and the transmittance τ(λ ₃ ) and calculates the calculated transmittance (transmittance τ(λ Any one of ₂ ) and the transmittance τ(λ ₃ )) may be used to calculate the temperature of the object 20 and/or the absolute amount or concentration of the absorber ABS.

In this way, the infrared detection device 10A functions as a radiation thermometer that calculates the temperature of the object 20 and/or a gas sensor that calculates the absolute amount or concentration of the absorber ABS.

[Selection method of wavelengths λ ₂ and λ ₃ ]
A method of selecting the wavelengths λ ₂ and λ ₃ based on the accuracy rating of the radiation thermometer and the measurement range of the temperature of the object 20 will be described.

As described above, in the second embodiment, the ratio of the black body spectral radiance is approximated to a certain value R _est , and the ratio of the spectral irradiance I(λ ₂ , T) and I(λ ₃ , T) is calculated. The temperature of the object 20 is calculated.

Spectral irradiance I(λ ₂ , T) detected by the infrared detection device 10A having the function of a radiation thermometer, transmittance τ _est (λ ₂ ) calculated by the infrared detection device 10A, and temperature calculated by the infrared detection device 10A. T _est1 satisfies the following equation.

By the method described above, the transmittance of the ratio of the spectral irradiance I(λ ₂ , T), I(λ ₃ , T) and the approximate value R _est of the ratio of the blackbody spectral radiance set in the infrared detection device 10A When the ratio τ _est (λ ₃ )/τ _est (λ ₂ ) is calculated, the following equation is obtained.

In Expression (16), the approximate value R _est is calculated in the measurement range of the temperature of the object 20, and thus the value in the measurement range of the temperature of the object 20 may be used as R _est . For example, R _est may be an average value or a median value.

By applying the equations (1) and (5) to the equation (16), the following equation is obtained.

The ratio of the equation (17), R (T) is blackbody spectral radiance B at a wavelength λ ₃ (λ _3, T) and the black body spectral radiance B at a wavelength _{λ 2 (λ 2, T)} (= B(λ ₃ , T)/B(λ ₂ , T)).

Expression (17) is the ratio R(T) of the black body spectral radiance B(λ ₃ , T) and the black body spectral radiance B(λ ₂ , T), and the black body set in the infrared detection device 10A. It is shown that the quotient of the ratio of spectral radiance and the approximate value R _est is an error element of the transmittance τ _est (λ ₂ ) calculated by the infrared detection device 10A.

Substituting equation (17) into equation (15) and applying equation (2), the following equation is obtained.

Formula (18) is the spectral irradiance I(λ ₂ , T), I(λ ₃ , T) detected by the infrared detection device 10A, the detection ratio α, and the known emissivity ε(λ ₂ ), ε( It is shown that the temperature T _{est1 of the} object 20 can be calculated by λ ₃ ).

On the other hand, by substituting equation (17) and equation (1) into equation (15), the following equation is obtained.

Then, when the equation (19) is approximately solved under the equation (16) according to the premise of the second embodiment, the following equation is obtained.

In this case, the conditions 1) and 2) described above were considered. According to the conditions 1) and 2), R(T) is close to 1 and has a small temperature dependence, and can be approximated by the ratio R _est of the black body spectral radiance set in the infrared detection device 10A.

In the design of the radiation thermometer, it is necessary to define the minimum temperature T _min and the maximum temperature T _max as the measurement range of the temperature of the object 20. Further, the radiation thermometer needs to be able to calculate the temperature with higher accuracy than _a certain accuracy rating Ta. That is, the detection wavelength of the radiation thermometer must be designed so as to satisfy the accuracy rating Ta in _a certain measurement range. The accuracy rating T _a defines the accuracy of the calculated temperature.
(Calculation temperature 1 and accuracy rating)
_Let T _est1 in equation (20) be the calculated temperature 1, and define the calculation error 1 by (T _est1 −T). In this case, the second term on the right side of Expression (20) becomes the calculation error.

That is, as shown in equation (21), the absolute value of the calculated error in accuracy rating of the radiation thermometer absolute value of _{(T a),} the measurement range of the temperature of the object _{20 ([T min ~T max]} ) ( It is necessary to set the value larger than | _Test1- T|).

Detection wavelength lambda _2, lambda _3, in the measurement range of the temperature of the object 20, shown in equation (21) _| may be selected from detection wavelength satisfying _{<T a} | _T est1 -T. Specifically, ₂ available lambda, lambda ₃ in combination _{| T est1} -T | is calculated and may be selected a combination which is less than _{T a.}
(Calculation temperature 2 and accuracy rating)
By calculating the temperature (T _est1 ) of the target object 20 calculated by the radiation thermometer by the above-described method, then correcting the T _est1 to calculate the temperature (T) of the target object 20 with higher accuracy. You can For example, _Test2 in Expression (22) is _defined as the calculated temperature 2, and the calculation error 2 is defined as ( _Test2- T).

Formula (22) is a formula for calculating the temperature (T) of the object 20 based on formula (20), which holds when the second term on the right side of formula (20) is sufficiently small.

According to equation (23), the absolute value of the calculated error in accuracy rating of the radiation thermometer absolute value of _{(T a),} the measurement range of the temperature of the object _{20 ([T min ~T max]} ) (| T est2 - It is necessary to set the value larger than T|).

The calculation of the temperature of the object 20 calculated by the corrected radiation thermometer does not necessarily need to use Expression (22), and the correction function may be determined by simulation.

Detection wavelength lambda _2, lambda _3, in the measurement range of the temperature of the object 20, shown in equation (23) _| may be selected from detection wavelength satisfying _{<T a} | _T est2 -T. Specifically, ₂ available lambda, lambda ₃ in combination _{| T est2} -T | is calculated and may be selected a combination which is less than _{T a.}

FIG. 10 is a flowchart showing a selection method for selecting the _two wavelengths λ ₂ and λ ₃ based on the accuracy rating of the radiation thermometer and the measurement range of the temperature of the object.

Referring to FIG. 10, when the operation of selecting the _two wavelengths λ ₂ and λ ₃ is started, the wavelength selection unit 44 causes the black body spectral radiance approximate value R _est and the black body spectral radiance B to be approximately R _est . The ratio B(λ ₃ , T)/B(λ ₂ , T) of the black body spectral radiance B(λ ₃ , T) to (λ ₂ , T) and the ratio ε _a (λ ₃ )/ε _{a of the} extinction coefficient. The calculated temperature T _est1 of the object 20 is calculated using the calculation error ΔT _est calculated based on (λ ₂ ) (step S31). That is, the wavelength selection unit 44 calculates the calculated temperature T _est1 by the formula (20).

Then, the wavelength selection unit 44 calculates the absolute value | _Test1- T| of the difference between the calculated temperature _Test1 and the temperature T of the object 20 (step S32).

After that, the wavelength selection unit 44 sets the absolute value |T _est1 −T| to be smaller than the absolute value |T _a | of the accuracy rating T _a in the measurement range (T _{min to} T _max ) of the temperature of the object 20. To select _two wavelengths λ ₂ and λ ₃ (step S33). This completes the operation of selecting the _two wavelengths λ ₂ and λ ₃ .

FIG. 11 is a flowchart showing another selection method for selecting the _two wavelengths λ ₂ and λ ₃ based on the accuracy rating of the radiation thermometer and the measurement range of the temperature of the object.

With reference to FIG. 11, when the operation of selecting the _two wavelengths λ ₂ and λ ₃ is started, the wavelength selection unit 44 causes the detection ratio α, the emissivity ε(λ ₂ ), ε(λ ₃ ), and the spectroscopy. Based on the approximate value R _est of the ratio of the irradiances I(λ ₂ , T), I(λ ₂ , T) and the black body spectral radiance, the extinction coefficient ratio ε _a (λ ₃ )/ε _a (λ ₂ ) _{Is used} to calculate the parallel root of the estimated transmittance ratio, and the calculated temperature T _est1 of the object 20 is calculated (step S41). That is, the wavelength selection unit 44 calculates the calculated temperature T _est1 by the equation (18).

Then, the wavelength selection unit 44 calculates the calculated temperature _{T est2} by correcting the calculated temperature _{T est1} (step S42). That is, the wavelength selection unit 44 calculates the calculated temperature _{T est2} the calculated calculated temperature _{T est1} into Equation (22). In this case, the wavelength selection unit 44 holds in advance a brightness table indicating the relationship between the temperature and the wavelength and the black body spectral radiance, and the black body spectral radiance B(λ ₂ , T _est1 ), B(λ ₃ , T _est1 ), and based on the detected black body spectral radiance B(λ ₂ , T _est1 ), B(λ ₃ , T _est1 ) of the black body spectral radiance _{Calculate the} ratio R(T _est1 )=B(λ ₃ , T _est1 )/B(λ ₂ , T _est1 ).

After step S42, the wavelength selection unit 44 calculates the absolute value | _Test2- T| of the difference between the calculated temperature _Test2 and the temperature T of the target object 20 (step S43).

Thereafter, the wavelength selection unit 44, the measurement range of the temperature of the object 20 _(T min _{~T max),} the absolute value _{| T est2} -T | is the absolute value of the accuracy rating _{T a} | _{T a} | smaller than as To select _two wavelengths λ ₂ and λ ₃ (step S44). This completes the operation of selecting the _two wavelengths λ ₂ and λ ₃ .

The wavelength selection unit 44 selects two wavelengths λ ₂ and λ ₃ according to the flowchart shown in FIG. 10 or the flowchart shown in FIG. 11, and outputs the selected two wavelengths λ ₂ and λ ₃ to the calculation unit 4A.

Note that in the second embodiment, the operation of selecting the _two wavelengths λ ₂ and λ ₃ based on the accuracy rating of the radiation thermometer and the measurement range of the temperature of the object may be executed by software. In this case, the calculation unit 4A includes a CPU, ROM and RAM.

The ROM receives the spectral irradiance I(λ ₂ , T) and the spectral irradiance I(λ ₃ , T) from the detectors 2 and 3, respectively, at step S1-1A, and the emissivity via the input device (keyboard or the like). A program Prog_C including step S1-2A for receiving ε(λ ₂ ), ε(λ ₃ ) and extinction coefficients ε _a (λ ₂ ), ε _a (λ ₃ ), and steps S31 to S33 shown in FIG. Alternatively, step S1-1A for receiving the spectral irradiance I(λ ₂ , T) and the spectral irradiance I(λ ₃ , T) from the detectors 2 and 3, respectively, and the emissivity ε( via the input device (keyboard or the like). A program Prog_D including step S1-2A for receiving λ ₂ ), ε(λ ₃ ) and extinction coefficients ε _a (λ ₂ ), ε _a (λ ₃ ) and steps S41 to S44 shown in FIG. 11 is stored. .. The ROM also stores the transmittance calculation table 42 and the brightness ratio parameter 43 shown in FIG. 7. The RAM has the spectral irradiances I(λ ₂ , T), I(λ ₃ , T), emissivity ε(λ ₂ ), ε(λ ₃ ) and extinction coefficient ε _a (λ ₂ ), which are received by the CPU. ε _a (λ ₃ ), the approximate value R _est of the ratio of the black body spectral radiance detected by the CPU, the ratio ε _a (λ ₃ )/ε _a (λ ₂ ) of the extinction coefficient calculated by the CPU, The calculated calculation error ΔT _est , the calculated temperatures T _est1 and T _est2 calculated by the CPU, and the absolute values |T _est1 −T| and |T _est2 −T| calculated by the CPU are temporarily stored.

The CPU reads the program Prog_C or the program Prog_D from the ROM, executes the read program Prog_C or the program Prog_D, and selects the _two wavelengths λ ₂ and λ ₃ by the method described above.

In this case, the CPU that detects the approximate value R _est of the ratio of the black body spectral radiance constitutes “detection means”, and the ratio of extinction coefficients ε _a (λ ₃ )/ε _a (λ ₂ ), the calculated temperature T. _The CPU that calculates _est1 , T _est2 , and the absolute values |T _est1 −T|, |T _est2 −T| configures “calculating means”. Further, spectral irradiances I(λ ₂ , T), I(λ ₃ , T), emissivity ε(λ ₂ ), ε(λ ₃ ) and extinction coefficients ε _a (λ ₂ ), ε _a (λ ₃ ) The CPU that accepts "constitutes" constitutes "accepting means".

Further, the program Prog_C or the program Prog_D may be recorded in a recording medium (for example, CD and DVD) and distributed. In this case, the computer (CPU) reads the program Prog_C or the program Prog_D from the recording medium and executes the program to select the _two wavelengths λ ₂ and λ ₃ . Therefore, a CD, a DVD, or the like in which the program Prog_C or the program Prog_D is recorded is a computer (CPU) readable recording medium in which the program Prog_C or the program Prog_D is recorded.

As described above, can be calculated calculated temperature _{T est1} of the object 20 by equation (18) can be calculated to calculate the temperature _{T est2} object 20 by equation (22). Therefore, in the second embodiment, the temperature of the object 20 may be calculated using the equation (18) or the equation (22).

FIG. 12 is a flowchart showing a detection method for detecting the temperature of the target object 20 according to the second embodiment. The flowchart shown in FIG. 12 is the same as the flowchart shown in FIG. 9 except that steps S23 to S27 of the flowchart shown in FIG. 9 are replaced with steps S51 and S52.

With reference to FIG. 12, when the operation of detecting the temperature of the target object 20 is started, the calculation unit 4A sequentially executes steps S21 and S22 described above. Then, after step S22, the calculation unit 4A causes the spectral irradiance I(λ ₂ , T), I(λ ₃ , T), the emissivity ε(λ ₂ ), ε(λ ₃ ), and the extinction coefficient ratio ε. _{Based on a} (λ ₃ )/ε _a (λ ₂ ) and the approximate value R _est of the ratio of the black body spectral radiance, a root including the ratio ε _a (λ ₃ )/ε _a (λ ₂ ) of the extinction coefficient is found. The square root of the estimated transmittance ratio is calculated using the calculated temperature T _est1 of the object 20 (step S51). That is, the calculation unit 4A calculates the calculated temperature T _est1 by the equation (18).

The calculation unit 4A calculates the calculated temperature _{T est2} by correcting the calculated temperature _{T est1} (step S52). That is, the calculation unit 4A calculates the calculated temperature _{T est2} by correcting the calculated temperature _{T est1} by equation (22). As a result, the operation of detecting the temperature of the object 20 ends.

The detection method for detecting the temperature of the target object 20 is to calculate the calculated temperature T _est1 of the target object 20 according to steps S21, S22, and S51 shown in FIG. 12, and use the calculated calculated temperature T _est1 as the temperature of the target object 20. _{Alternatively} , the calculated temperature T _est2 of the object 20 may be calculated according to steps S21, S22, S51, and S52 shown in FIG. 12, and the calculated temperature T _est2 may be detected as the temperature of the object 20. Good.

Then, by detecting the calculated temperature T _est2 as the temperature of the object 20, than the case of detecting the calculated temperature T _est1 as the temperature of the object 20, the temperature of the object 20 can be detected with high accuracy.

Further, in the second embodiment, the operation of detecting the temperature of the target object 20 may be executed by software. In this case, the calculation unit 4A includes a CPU, ROM and RAM.

The ROM receives the spectral irradiance I(λ ₂ , T) and the spectral irradiance I(λ ₃ , T) from the detectors 2 and 3, respectively, at step S1-1A, and the emissivity via the input device (keyboard or the like). Step S1-2A for receiving ε(λ ₂ ), ε(λ ₃ ) and extinction coefficients ε _a (λ ₂ ), ε _a (λ ₃ ), and steps S22, S51, and S52 shown in FIG. Store the program Prog_E. The ROM also stores the transmittance calculation table 42 and the brightness ratio parameter 43 shown in FIG. 7. The RAM has the spectral irradiances I(λ ₂ , T), I(λ ₃ , T), emissivity ε(λ ₂ ), ε(λ ₃ ) and extinction coefficient ε _a (λ ₂ ), which are received by the CPU. ε _a (λ ₃ ), an approximate value R _est of the ratio of black body spectral radiance detected by the CPU, a ratio of extinction coefficients ε _a (λ ₃ )/ε _a (λ ₂ ), and a ratio of black body spectral radiance. The "root including the extinction coefficient ratio ε _a (λ ₃ )/ε _a (λ ₂ )" calculated by the CPU based on the approximate value R _est of the temperature and the temperatures T _est1 and T _est2 calculated by the CPU are temporarily Remember.

The CPU reads the program Prog_E from the ROM and sequentially executes steps S1-1A, S1-2A, S22, S51 or steps S1-1A, S1-2A, S22, S51, S52 of the read program Prog_C, The temperature of the object 20 is detected by the method described above.

In this case, the CPU that detects the approximate value R _est of the ratio of the black body spectral radiance constitutes “detecting means”, and the ratio of the extinction coefficients ε _a (λ ₃ )/ε _a (λ ₂ ) and the black body spectrum. CPU for calculating “root including extinction coefficient ratio ε _a (λ ₃ )/ε _a (λ ₂ )” and CPU for calculating temperatures T _est1 and T _est2 based on the approximate value R _est of the ratio of radiances Constitutes "calculation means". Further, spectral irradiances I(λ ₂ , T), I(λ ₃ , T), emissivity ε(λ ₂ ), ε(λ ₃ ) and extinction coefficients ε _a (λ ₂ ), ε _a (λ ₃ ) The CPU that accepts "constitutes" constitutes "accepting means".

Further, the program Prog_E may be recorded in a recording medium (for example, CD and DVD) and distributed. In this case, the computer (CPU) reads the program Prog_E from the recording medium and executes it to detect the temperature of the object 20. Therefore, a CD, a DVD, or the like in which the program Prog_E is recorded is a computer (CPU) readable recording medium in which the program Prog_E is recorded.
(Radiation thermometer corrected for the effect of water vapor)
When the ratio (ε(λ+0.5 μm)/ε(λ)) of the extinction coefficient by the absorber ABS is 1.5 or more or 0.67 or less, the detection wavelength λ _{2 of the} radiation thermometer is based on the second embodiment. , Λ ₃ is designed.

The wavelength (λ) is a wavelength belonging to a certain wavelength range. For example, in the extinction coefficient of water vapor, the above relationship is satisfied when the wavelength λ belongs to 6.5 to 9.5 μm or 11 to 15.5 μm.

For example, in an environment where water vapor is absorbed, a radiation thermometer that meets the accuracy rating ±2°C and measures the object 20 at -50 to 50°C is designed. According to the second embodiment, by using the equations (18) and (22), the accuracy rating is guaranteed when the detection wavelengths λ ₂ and λ ₃ are in the ranges of 6.5 to 10 μm and 11 to 15.5 μm. be able to.

In addition, a radiation thermometer that measures the object 20 at −20 to 120° C. and satisfies the accuracy rating of ±2° C. in an environment where water vapor is absorbed is designed. According to the second embodiment, by using the equations (18) and (22), the accuracy rating can be guaranteed in the detection wavelengths λ ₂ and λ ₃ in the range of 6.5 to 10 μm.

Furthermore, a radiation thermometer that measures the object 20 at 100 to 1000° C. and meets the accuracy rating of ±2° C. in an environment where water vapor is absorbed is designed. According to the second embodiment, by using the equations (18) and (22), the accuracy rating can be guaranteed in the detection wavelengths λ ₂ and λ ₃ in the range of 6.5 to 10 μm.
(Effect of using a detection wavelength longer than the peak wavelength)
When selecting the detection wavelength from the peak wavelength of the Wien's displacement law, it is possible to design a radiation thermometer that satisfies the same accuracy rating ±2°C and can measure a wider temperature range.

For example, a radiation thermometer is designed to measure the object 20 at −20 to 120° C. in an environment where water vapor is absorbed. According to the temperature of the target object 20 and the Wien's displacement law, the peak wavelength (λ _max ) of the black body spectral radiance is 7.4 to 11.4 μm. Therefore, the detection wavelengths λ ₂ and λ ₃ are set in the range of 11.4 to 16 μm on the long wavelength side of the peak wavelength. By using the equations (16) and (20) based on the second embodiment, the accuracy rating ±2°C can be guaranteed.

Further, a radiation thermometer that measures the object 20 at -50 to 1000° C. under the absorption environment of water vapor is designed. According to the temperature of the target object 20 and the Wien's displacement law, the peak wavelength (λ _max ) of the black body spectral radiance is 2.3 to 13 μm. Therefore, the detection wavelengths λ ₂ and λ ₃ are set in the range of 13 to 15.5 μm on the long wavelength side of the peak wavelength. By using the equations (16) and (20) based on the second embodiment, the accuracy rating ±2°C can be guaranteed.

[Temperature calculation accuracy]
It will be described that the infrared detector 10A according to the second embodiment can calculate the temperature with high accuracy in the presence of the absorber ABS.
(Setting of infrared detector)
First, the infrared detection device 10A is prepared in advance according to the second embodiment. Specific examples in the case where the absorber ABS is water vapor will be shown below.

For simplicity, the detection rate α is 0.1 and the emissivity ε is 1. The temperature of the target object 20 is 0 to 100°C.

Within the range of the atmospheric window shown in FIG. 3, the detection wavelength λ ₂ is set to 13.0 μm and the detection wavelength λ _{3 is set} to 13.5 μm. The brightness ratio parameter 43 and the transmittance calculation table 42 are preset in the calculation unit 4A. Further, the value of the brightness ratio parameter 43 is set to 0.947. For example, since the ratio of the black body spectral radiance when the temperature of the black body is 0 to 100° C. is 0.930 to 0.965, the ratio of the black body spectral radiance changes by about 3.6%.

The transmittance calculation table 42 refers to the ratio of extinction coefficients ε _a (λ ₂ )/ε _a (λ ₃ ) based on the formula (5) for calculating the transmittance from the transmittance ratio, for example, referring to FIG. And create it as 0.5. This is the ratio of the extinction coefficients of water vapor at wavelengths 13.0 μm and 13.5 μm.
(Calculation accuracy according to the second embodiment)
The calculation accuracy of the temperature in the second embodiment will be described based on the simulation. First, we created a simulation task. The transmittances τ(λ ₂ )=0.50 and τ(λ ₃ )=0.25 that match the adopted extinction coefficient ratio of 0.5 are set, and the spectra corresponding to the respective temperatures are set based on the equation (1). Irradiances I (13.0 μm, T) and I (13.5 μm, T) were calculated. This spectral irradiance was defined as the spectral irradiance detected by the detectors 2 and 3, and the temperature of the object 20 was calculated based on the second embodiment.

First, the temperature of the object 20 was calculated by the equation (18) from the ratio of the spectral irradiances I (13.0 μm, T), I (13.5 μm, T) and the spectral radiance ratio of 0.947.

FIG. 13 is a diagram showing a temperature difference between the set temperature of the target object 20 and the calculated temperature obtained by the simulation. In FIG. 13, the vertical axis represents the difference between the calculated temperature and the temperature of the target object 20, and the horizontal axis represents the temperature of the target object 20.

With reference to FIG. 13, even when the transmittance depends on the wavelength, the calculated temperature falls within an error of about −1.3° C. to +2.1° C. with respect to the temperature of the object 20. That is, assuming that the detection wavelength λ ₂ is 13.0 μm, the detection wavelength λ ₃ is 13.5 μm, and the ratio of the black body spectral radiance at these wavelengths is 0.947, the target object 20 has a temperature of 0 to 100° C. Within the temperature range, the temperature can be calculated with the accuracy of −1.3° C. to +2.1° C. by the formula (18).

Next, the corrected calculated temperature was calculated by the equation (22) from the calculated temperature and the spectral radiance ratio of 0.947.

FIG. 14 is a diagram showing a temperature difference between the set temperature of the target object 20 and the corrected calculated temperature obtained by the simulation. 14, the vertical axis represents the difference between the corrected calculated temperature and the temperature of the target object 20, and the horizontal axis represents the temperature of the target object 20.

Referring to FIG. 14, even when the transmittance depends on the wavelength, the corrected calculated temperature falls within an error of about −0.1° C. to +0.04° C. with respect to the temperature of the object 20. That is, assuming that the detection wavelength λ ₂ is 13.0 μm, the detection wavelength λ ₃ is 13.5 μm, and the ratio of the black body spectral radiance at these wavelengths is 0.947, the target object 20 has a temperature of 0 to 100° C. Within the temperature range, the temperature can be calculated with the accuracy of −0.1° C. to +0.04° C. by the formula (22).

[Effects of Second Embodiment]
The effect of the second embodiment will be described.
(Effects of radiation thermometer)
The effect of using the infrared detection device 10A according to the second embodiment as a radiation thermometer will be described.

In the conventional monochromatic method, the temperature is calculated by setting the transmittance to a value that is predicted in advance. Therefore, if the transmittance differs from the value, a calculation error occurs in the temperature. For example, assume that a monochromatic radiation thermometer that detects infrared rays with a detection wavelength of 8.5 μm is used, and that the transmittance should be set to 0.77 when the transmittance should be set to 0.77. That is, the radiation thermometer estimates the spectral radiance of the object 20 to be 0.77 times the original value. Under this condition, when the object 20 at 35° C. is detected according to the equation (1), the calculated temperature becomes about 21° C., which causes a large error. Further, in the conventional two-color method, since the transmittance has wavelength dependency, it is not possible to calculate the temperature with high accuracy. In the conventional two-color method, the temperature is calculated on the assumption that the transmittance does not depend on the wavelength. Therefore, when the actual transmittance has the wavelength dependency, a calculation error occurs in the temperature.

For example, using a conventional dichroic radiation thermometer that detects infrared rays having a detection wavelength of 8.5 μm and infrared rays having a detection wavelength of 13.0 μm, the transmittance is τ(8.5 μm)=0.77 and τ(13 .0)=0.5, the case where the temperature of the target object 20 is calculated is assumed. Under this condition, if the ratio of the spectral irradiance is regarded as the ratio of Planck's equation and the temperature is calculated, the object 20 at 35° C. is calculated as 137° C.

On the other hand, as shown in the simulation and FIGS. 13 and 14, the infrared detection device 10A according to the second embodiment can accurately calculate the temperature even when the transmittance depends on the wavelength. That is, the infrared detection device 10A according to the second embodiment has a transmittance correction function that is not found in conventional radiation thermometers.

In the second embodiment, the transmittance correction function can be added by using the fact that the temperature dependence of the ratio of the black body spectral radiance is reduced for the two wavelengths in the long wavelength region. Thereby, for example, in an environment where the transmittance greatly changes due to the influence of water vapor (for example, outdoors in bad weather such as rain or fog, a bathroom, etc.), it is possible to improve the detection performance of humans or animals. That is, it is possible to detect a person or an animal from a greater distance in bad weather and to detect an accident in a bathroom early.

Further, according to the infrared detection device 10A according to the second embodiment, it is possible to calculate the temperature with high accuracy by using the detection wavelengths λ ₂ and λ ₃ whose transmittance can be reduced due to the presence of the absorber such as water vapor. For example, the outside of the range of the atmospheric window, which has been conventionally unsuitable, can be used as the detection wavelength. That is, even when the detection wavelengths λ ₂ and λ ₃ belong to ₃ to 3.5 μm, 4.5 to 8 μm or 13 to 16 μm, the temperature and the transmittance can be calculated with high accuracy.

Since the absorber ABS existing between the object 20 and the infrared detection device 10A is determined by the wavelengths λ ₂ and λ ₃ , especially in the atmosphere, the type of the absorber ABS is inspected in advance. No need.
(Effects on gas sensor)
The effect of using the infrared detection device 10A according to the second embodiment as a gas sensor will be described.

The infrared detection device 10A according to the second embodiment can calculate the transmittance of the absorber ABS and at the same time calculate the absolute amount of the absorber ABS. When the distance between the object 20 and the infrared detection device 10A is known, the concentration of the absorber can be calculated. For example, if the absorber is water vapor, the amount of water vapor and the humidity at the distance between the object 20 and the infrared detection device 10A can be calculated. The target absorber ABS is not limited to water vapor, but may be a gas absorber such as carbon dioxide or a scatterer such as an aerosol.

With the infrared detection device 10A according to the second embodiment, the concentration of the absorber can be calculated with high accuracy as long as the temperature of the target object 20 is within a certain range. That is, for example, as compared with a gas sensor using an infrared detector typified by Patent Document 3, the infrared detection device 10A according to the second embodiment does not require a light source as a constituent element. Therefore, in a situation where it is difficult to install a light source or a situation where energy consumption is desired to be suppressed, calculation of gas concentration using the infrared detection device 10A according to the second embodiment is very effective. That is, since the infrared detection device 10A can be used as a space-saving and energy-saving gas sensor, it can be used as an IoT device in which a large number of sensors need to be arranged.

Since the absorber existing between the object 20 and the infrared detection device 10A is determined by the wavelengths λ ₂ and λ ₃ , it is not necessary to inspect the type of the absorber in advance especially in the atmosphere. Absent.

The distance between the object 20 and the infrared detection device 10A may be measured in advance if the object 20 and the infrared detection device 10A are fixed. When the infrared detection device 10A is provided with a lens, the focal length of the lens may be the distance between the object 20 and the infrared detection device 10A.
(Effects of radiation thermometer and gas sensor)
The effect when the infrared detection device 10A according to the second embodiment is used as a detection device having both functions of a radiation thermometer and a gas sensor will be described.

Which gas species the infrared detection device 10A according to the second embodiment detects depends on whether or not the detection wavelength has absorption. For example, with water vapor, the humidity can be calculated while measuring the temperature of the object 20 regardless of whether it is indoors or outdoors. In Patent Document 2, a hygrometer is provided, but this hygrometer measures the humidity in the vicinity of the radiation thermometer.

On the other hand, the infrared detection device 10A according to the second embodiment measures the average humidity from the object 20 to the detectors 2 and 3. Therefore, in a situation where the environment between the object 20 and the detectors 2 and 3 is significantly different, the calculation of temperature and humidity using the infrared detection device 10A according to the second embodiment is very effective. That is, since the infrared detection device 10A according to the second embodiment can be used to detect the temperature and the amount of water vapor in a cooking utensil in which water vapor is retained, the user or the cooking utensil itself determines the cooking state and provides feedback. can do.

For example, if the gas type to be detected is carbon dioxide, the carbon dioxide concentration can be calculated while measuring the temperature of the object regardless of whether it is indoors or outdoors. Patent Document 4 is a gas sensor that detects the carbon dioxide concentration, and this gas sensor measures the carbon dioxide concentration near the installation location.

On the other hand, the infrared detection device 10A according to the second embodiment measures the average carbon dioxide concentration from the object 20 to the detectors 2 and 3. Therefore, in a situation where the environment between the object 20 and the detectors 2 and 3 is greatly different, the calculation of the temperature and the carbon dioxide concentration using the infrared detection device 10A according to the second embodiment is very effective. That is, in the ventilation equipment and the air conditioning equipment for adjusting the carbon dioxide concentration, the infrared detection device 10A according to the second embodiment can be used for detecting the indoor/outdoor carbon dioxide concentration and so on. The air conditioner itself can determine the state of carbon dioxide concentration and feed it back.

If the target to be detected is not an absorber such as gas but a scatterer such as aerosol, the concentration of the scatterer can be calculated while measuring the temperature of the target. That is, in the ventilation equipment, the air conditioning equipment, and the air purifier, since the infrared detection device 10A according to the second embodiment can be used for detecting scatterers, the user or the ventilation equipment, the air conditioning equipment, and the air purifier itself. Can judge the state of the concentration of the scatterer and feed it back.
(Effects of radiation thermometer and gas sensor for measuring substantial temperature)
Since the infrared detection device 10A according to the second embodiment can simultaneously detect the temperature and the concentration of the absorber, the infrared detection device 10A can be used as a device for measuring the substantial temperature or the comfort index calculated from the temperature of the object 20 and the concentration of the absorber. It is suitable. For example, by detecting the temperature and the humidity at the same time, the substantial temperature calculated from the temperature and the humidity can be measured. The substantial temperature includes, for example, a sensible temperature, which is a temperature felt by a person, and an effective heating temperature applied to food by a cooking device. Generally, as the temperature and humidity of the object 20 increase, the substantial temperature increases.

A suitable wavelength for calculating the substantial temperature will be described. As described above, in the second embodiment, when the temperature of the target object 20 changes, the ratio of the black body spectral radiance slightly changes, so that a calculation error occurs in the temperature and the transmittance of the target object 20. That is, the accuracy of calculating the temperature and the transmittance of the object 20 depends on the accuracy of dividing the ratio of the black body spectral radiance and the ratio of the transmittance.

On the other hand, even if the difference between the temperature of the object 20 and the transmittance is accompanied by an error, the substantial temperature can be calculated with high accuracy. For example, regardless of whether the value of temperature or humidity is increased, under the condition that the ratio of the spectral irradiance increases, the calculation error due to the carving can be canceled out, so that the actual temperature must be calculated with high accuracy. You can In other words, due to experimental error and deviation from the transmission model, the temperature and humidity are not sufficiently separated, and even if the humidity is calculated higher (lower) than it actually is, the temperature is calculated lower (higher), so When converted to, the calculation error becomes smaller. In other words, the substantial temperature can be calculated with high accuracy by selecting the wavelength so that the correlation between the substantial temperature and the ratio of the spectral irradiance becomes large.

When the detection wavelengths λ ₂ and λ ₃ are set to λ ₂ <λ ₃ according to the second embodiment, when the temperature of the object 20 increases, the blackbody spectroscopy of the detection wavelengths λ ₂ and λ ₃ is caused by the property of Planck's equation. The irradiance ratio (B(λ ₂ , T)/B(λ ₃ , T)) increases. In other words, as the temperature of the object 20 increases, the ratio of the spectral irradiances of the detector 2 and the detector 3 (I(λ ₂ , T)/I(λ ₃ , T)) increases.

Therefore, if the wavelengths λ ₂ and λ _{3 in} which the transmittance ratio (τ(λ ₂ )/τ(λ ₃ )) increases with an increase in humidity are selected, the spectral radiation of the detector 2 and the detector 3 will be increased. The illuminance ratio (I(λ ₂ , T)/I(λ ₃ , T)) also increases, and the substantial temperature calculation error due to the temperature/humidity separation error is reduced.

Here, a schematic diagram of the relationship between the transmittance of water vapor at a certain humidity and the wavelength is shown in FIG. In the wavelength region of 3.0 to 16 μm, the water vapor transmission rate can be classified into three types: a high transmission rate region, a first low transmission rate region, and a second low transmission rate region. The high transmittance region is a wavelength region showing a high transmittance of 3.5 to 4.5 μm and 8.0 to 13.0 μm. The first low transmittance region is a low transmittance region of 3.0 to 3.5 μm and 6.0 to 8.0 μm and a wavelength region where the transmittance increases as the wavelength becomes longer. The second low transmittance region is a low transmittance region of 4.5 to 6.0 μm and 13.0 to 16.0 μm and a wavelength region where the transmittance decreases as the wavelength becomes longer.

According to the Lambert-Beer law shown in the equation (4), there is a negative correlation between the transmittance and the extinction coefficient at the same absorber concentration. That is, the wavelength condition under which the transmittance ratio (τ(λ ₂ )/τ(λ ₃ )) increases with increasing humidity satisfies τ(λ ₂ )>τ(λ ₃ ) in FIG. Wavelength. That is, when the detection wavelength λ ₂ belongs to the high transmittance region and the detection wavelength λ ₃ belongs to the adjacent low transmittance region (that is, the second low transmittance region), and the detection wavelengths λ ₂ and λ ₃ Belong to the same second low transmittance region.

That is, when the detection wavelength λ ₂ belongs to the range of 3.5 to 4.5 μm and the detection wavelength λ ₃ belongs to the range of 4.5 to 6.0 μm, the substantial temperature can be calculated with high accuracy. it can. Alternatively, when the detection wavelength λ ₂ belongs to the range of 8.0 to 13.0 μm and the detection wavelength λ ₃ belongs to the range of 13.0 to 16.0 μm, the substantial temperature can be calculated with high accuracy. .. Alternatively, when the detection wavelengths λ ₂ and λ ₃ belong to the range of 4.5 to 6.0 μm, the substantial temperature can be calculated with high accuracy. Alternatively, when the detection wavelengths λ ₂ and λ ₃ belong to the range of 13.0 to 16.0 μm, the substantial temperature can be calculated with high accuracy.

Regarding the calculation of the actual temperature, the calculation unit for calculating the actual temperature directly from the spectral irradiance of the detection wavelengths λ ₂ and λ ₃ is used instead of the brightness ratio parameter 43 and the transmittance calculation table 42. It may be arranged at 4A.
(Effects of radiation thermometer and gas sensor for measuring comfort index)
The comfort index may be calculated based on not only the actual temperature but also the temperature and the carbon dioxide concentration or the temperature and the aerosol concentration. As a result, the user, the cooker, the ventilation device, the air conditioner, and the air purifier can perform feed back by making judgments based on the substantial temperature and the index of comfort.

With respect to the comfort index that decreases when the temperature and the carbon dioxide concentration increase, a suitable wavelength will be described. Similar to the case of the substantial temperature, the condition that can reduce the error in separating the temperature of the object 20 and the transmittance is that the ratio of the transmittance (τ(λ ₂ )/τ( with respect to the increase of the carbon dioxide concentration). There are two detection wavelengths that increase λ ₃ )).

Here, a schematic diagram of the relationship between the carbon dioxide transmittance and the wavelength at a certain humidity is shown in FIG. In the case of carbon dioxide transmittance, the wavelength range of 3.0 to 16 μm can be classified into three types: a high transmittance area, a second low transmittance area, and a third low transmittance area. The high transmittance region is a wavelength region showing a high transmittance of 3.5 to 4.0 μm and 4.5 to 13.5 μm. The second low transmittance region is a low transmittance region of 13.5-16.0 μm and a wavelength region in which the transmittance decreases as the wavelength becomes longer. The third low transmittance region is a wavelength region showing a low transmittance of 4.0 to 4.5 μm.

According to the Lambert-Beer law shown in the equation (4), there is a negative correlation between the transmittance and the extinction coefficient at the same absorber concentration. That is, the wavelength condition in which the transmittance ratio (τ(λ ₂ )/τ(λ ₃ )) increases with increasing humidity satisfies τ(λ ₂ )>τ(λ ₃ ) in FIG. Wavelength. That is, when the detection wavelength λ ₂ belongs to the high transmittance region and the detection wavelength λ ₃ belongs to the adjacent low transmittance region (that is, the second low transmittance region), and the detection wavelengths λ ₂ and λ ₃ Belong to the same second low transmittance region.

That is, when the detection wavelength λ ₂ is in the range of 3.5 to 4.0 μm and the detection wavelength λ ₃ is in the range of 4.0 to 4.5 μm, the comfort index can be calculated with high accuracy. it can. Alternatively, when the detection wavelength λ ₂ belongs to the range of 4.5 to 13.5 μm and the detection wavelength λ ₃ belongs to the range of 13.5 to 16.0 μm, the comfort index can be calculated with high accuracy. .. Alternatively, when the detection wavelengths λ ₂ and λ ₃ belong to the range of 13.5 to 16.0 μm, the comfort index can be calculated with high accuracy.

Regarding the calculation of the comfort index, the calculation parameter for directly calculating the comfort index from the spectral irradiance of the detection wavelengths λ ₂ and λ ₃ is used instead of the brightness ratio parameter 43 and the transmittance calculation table 42. It may be arranged at 4A.
(Effects of Application of Second Embodiment)
In the second embodiment, the emissivity needs to be known. This is because it is known that the object 20 is a person, an animal, a cooking utensil, a cooking utensil material, etc. Good.

The infrared detection device 10A according to the second embodiment can be used as an infrared camera by forming an array. The infrared camera to which the infrared detection device 10A is applied can simultaneously capture both an image regarding the temperature of the target object 20 and an image regarding the absolute amount of the absorber. With this function, the contour and distribution of the object 20 can be determined with higher accuracy.

The other description in the second embodiment is the same as the description in the first embodiment.

[Third Embodiment]
FIG. 15 is a schematic diagram of an infrared detection device according to the third embodiment. Referring to FIG. 15, an infrared detection device 10B according to the third embodiment has a configuration in which the calculation unit 4A of the infrared detection device 10A shown in FIG. 7 is replaced with a calculation unit 4B, and the detector 1 in the first embodiment is added. Yes, others are the same as the infrared detection device 10A.

The detector 1 detects the spectral irradiance I(λ ₁ , T) of the infrared IFR 1 having the wavelength λ ₁ (<λ ₂ ) and sends the detected spectral irradiance I(λ ₁ , T) to the calculation unit 4B. Output. The wavelength λ ₁ may be longer or shorter than the above-mentioned peak wavelength λ _max .

Among the detectors 1 to 3, two or three detectors may be the same as or different from each other. When the detectors 1 to 3 or two detectors of the detectors 1 to 3 are the same, that is, when the detectors 1 to 3 are composed of one or two detectors, the detectors 1 to 1 The detectors responsible for multiple detections of 3 are quantum dot detectors or quantum well detectors. The quantum dot detector or the quantum well detector can control the detection wavelength according to the applied voltage. As a result, only one detector is required, and the infrared detector 10B can be downsized and reduced in cost. When the detectors 1 to 3 are configured by one or two detectors, the infrared detection device 10B controls the voltage applied to the detector (which is a quantum dot detector or a quantum well detector), The control part which controls the wavelength to detect is further provided. When the detectors 1 to 3 are configured by one detector, the control unit controls the voltage V ₁ for setting the wavelength to be detected at the wavelength λ ₁ and the voltage V ₁ for setting the wavelength to be detected at the wavelength λ _2. has a V _2, the voltage V ₃ for setting the wavelength for detecting the wavelength lambda _3, the three functions of controlling the. When the detectors 1 to 3 are composed of two detectors, the control unit controls the voltage V ₁ for setting the wavelength to be detected to the wavelength λ ₁ and the voltage V ₁ to set the wavelength to be detected to the wavelength λ _2. has a V _2, the voltage V ₃ for setting the wavelength for detecting the wavelength lambda _3, the two functions of the three functions of controlling the.

The calculation unit 4B is obtained by adding a transmittance calculation table 45 to the calculation unit 4A shown in FIG. Transmittance calculation table 45, the wavelength lambda _2, the wavelength lambda _3, and the wavelength lambda _2, any of the transmittance of both _{λ 3 (τ (λ 1)} , τ (λ 2) and τ (λ _1), τ It is a table for calculating the transmittance τ(λ ₁ ) from (any one of λ ₂ ).

In the third embodiment, as in the second embodiment, the wavelengths λ ₂ and λ ₃ are selected based on the accuracy rating of the radiation thermometer and the measurement range of the temperature of the object 20, and the black body spectral radiance is selected. It is used that the temperature dependence of the ratio of B(λ ₂ , T) and black body spectral radiance B(λ ₃ , T) is small. That is, the approximate value R _est of the ratio of the black body spectral radiance B(λ ₂ , T) and the black body spectral radiance B(λ ₃ , T) is used. Further, in the third embodiment, emissivity ε(λ ₁ ), ε(λ ₂ ), ε(λ ₃ ) and extinction coefficients ε _a (λ ₁ ), ε _a (λ ₂ ), ε _a (λ ₃ ). ) Shall be known.

The calculator 4B receives the spectral irradiances I(λ ₁ , T) to I(λ ₃ , T) from the detectors 1 to 3, respectively. Further, the calculation unit 4B detects the approximate value R _est from the brightness ratio parameter 43. Then, the calculation unit 4B calculates an approximate value of the ratio of the spectral irradiances I(λ ₂ , T), I(λ ₃ , T), the emissivity ε(λ ₂ ), ε(λ ₃ ) and the blackbody spectral radiance. Substituting R _est into equation (12), the transmittance ratio τ(λ ₂ )/τ(λ ₃ ) is calculated. In this case, the calculation unit 4B substitutes the approximate value R _est into R of the equation (12).

Then, calculating unit 4B is calculated transmittance ratio τ (λ ₂₎ / τ is calculated transmittance tau a (lambda ₂₎ on the basis of (λ _3). More specifically, the calculation unit 4B is calculated ratio of the transmittance _{τ (λ 2) / τ (} λ 3) to apply the formula (5) is calculated transmittance tau a (lambda _2). Further, the calculation unit 4B uses the transmittance calculation table 42 to detect the transmittance τ(λ ₂ ) corresponding to the calculated transmittance ratio τ(λ ₂ )/τ(λ ₃ ). The transmittance τ(λ ₂ ) is calculated from the ratio τ(λ ₂ )/τ(λ ₃ ).

When the Lambert-Beer law holds for the wavelengths λ ₁ and λ ₂ , the following equation holds between the transmittance τ(λ ₁ ) and the transmittance τ(λ ₂ ).

Therefore, when calculating the transmittance τ(λ ₂ ), the calculator 4B calculates the transmittance τ(λ ₁ ) based on the calculated transmittance τ(λ ₂ ). More specifically, the calculation unit 4B substitutes the calculated transmittance τ(λ ₂ ) and the extinction coefficients ε _a (λ ₁ ), ε _a (λ ₂ ) into the equation (24), and the transmittance τ. Calculate (λ ₁ ). Further, the calculation unit 4B uses the transmittance calculation table 45 to detect the transmittance τ(λ ₁ ) corresponding to the calculated transmittance τ(λ ₂ ), and thereby the transmittance τ(λ ₂ ) to the transmittance τ(λ ₂ ). Calculate τ(λ ₁ ).

Then, the calculation unit 4B causes the spectral irradiances I(λ ₁ , T), I(λ ₂ , T), the transmittances τ(λ ₁ ), τ(λ ₂ ) and the emissivity ε(λ ₁ ), ε(. λ ₂ ) is substituted into equation (3) to calculate the black body spectral radiance ratio B(λ ₂ , T)/B(λ ₁ , T).

When the temperature of the object 20 is calculated by the two-color method, the black body spectral radiance ratio B(λ ₁ , T)/B(λ ₂ , T) is expressed by the following equation.

従って、算出部４Ｂは、黒体分光放射輝度の比Ｂ（λ_２，Ｔ）／Ｂ（λ_１，Ｔ）を算出すると、その算出した黒体分光放射輝度の比Ｂ（λ_２，Ｔ）／Ｂ（λ_１，Ｔ）を式（２５）に代入して対象物２０の温度Ｔを算出する。

Therefore, when the calculating unit 4B calculates the black body spectral radiance ratio B(λ ₂ , T)/B(λ ₁ , T), the calculated black body spectral radiance ratio B(λ ₂ , T). Substituting /B(λ ₁ , T) into the equation (25), the temperature T of the object 20 is calculated.

FIG. 16 is a flowchart for explaining the detection method according to the third embodiment for detecting the temperature of the object 20 and/or the absolute amount or concentration of the absorber.

The flowchart shown in FIG. 16 is obtained by replacing steps S21, S25, S26 of the flowchart shown in FIG. 9 with steps S21A, S25A, S26A, respectively, and replacing step S27 with steps S28, S29. It is the same as the flowchart.

With reference to FIG. 16, when the operation of detecting the temperature of the object 20 and/or the absolute amount or concentration of the absorber is started, the detectors 1 to 3 cause the spectral irradiances I(λ ₁ , T, respectively). ), I(λ ₂ , T), I(λ ₃ , T) are detected (step S21A), and the detected spectral irradiances I(λ ₁ , T), I(λ ₂ , T), I(λ ₃ ,T) is output to the calculation unit 4B.

Then, step S22 to step S24 described above are sequentially executed. Then, after step S24, the calculation unit 4B calculates the transmittance τ(λ ₁ ) based on the calculated transmittance τ(λ ₂ ) (step S25A). More specifically, the calculation unit 4B substitutes the calculated transmittance τ(λ ₂ ) and the extinction coefficients ε _a (λ ₁ ), ε _a (λ ₂ ) into the equation (24), and the transmittance τ. Calculate (λ ₁ ). Further, the calculation unit 4B uses the transmittance calculation table 45 to detect the transmittance τ(λ ₁ ) corresponding to the calculated transmittance τ(λ ₂ ), and thereby the transmittance τ(λ ₂ ) to the transmittance τ(λ ₂ ). Calculate τ(λ ₁ ).

After step S25A, the calculation unit 4B causes the spectral irradiances I(λ ₁ , T), I(λ ₂ , T), the transmittances τ(λ ₁ ), τ(λ ₂ ) and the emissivity ε(λ ₁ ). , Ε(λ ₂ ) is substituted into the equation (3) to calculate the black body spectral radiance ratio I(λ ₂ , T)/I(λ ₁ , T) (step S26A).

Subsequently, the calculation unit 4B calculates the temperature T of the target object 20 by substituting the calculated black body spectral radiance ratio I(λ ₂ , T)/I(λ ₁ , T) into the equation (25). (Step S28). Then, the calculation unit 4B calculates the absolute amount or concentration of the absorber ABS based on the transmittance τ(λ ₁ ) or the transmittance τ(λ ₂ ) (step S29). This ends the operation of detecting the temperature of the object 20 and/or the absolute amount or concentration of the absorber.

In the third embodiment, the operation of detecting the temperature of the object 20 and/or the absolute amount or concentration of the absorber ABS may be executed by software. In this case, the calculation unit 4B includes a CPU, ROM and RAM.

The ROM receives step S1-1B of the spectral irradiance I(λ ₁ , T), the spectral irradiance I(λ ₂ , T), and the spectral irradiance I(λ ₃ , T) from the detectors 1 to 3, respectively. Emissivity ε(λ ₁ ), ε(λ ₂ ), ε(λ ₃ ) and extinction coefficients ε _a (λ ₁ ), ε _a (λ ₂ ), ε _a (λ ₃ ) via an input device (keyboard or the like). ) Is received, and a program Prog_F including steps S22 to S24, S25A, S26A, S28, and S29 shown in FIG. 16 is stored. The ROM also stores the transmittance calculation table 42, the brightness ratio parameter 43, and the transmittance calculation table 45 shown in FIG. The RAM has the spectral irradiances I(λ ₁ , T), I(λ ₂ , T), I(λ ₃ , T), emissivity ε(λ ₁ ), ε(λ ₂ ), ε that are received by the CPU. (Λ ₃ ) and extinction coefficient ε _a (λ ₁ ), ε _a (λ ₂ ), ε _a (λ ₃ ), an approximate value R _est of the ratio of the blackbody spectral radiance detected by the CPU, calculated by the CPU Based on the transmittance ratio τ(λ ₂ )/τ(λ ₃ ), the transmittance ratio τ(λ ₂ )/τ(λ ₃ ), and the extinction coefficient ε _a (λ ₂ ), ε _a (λ ₃ ). The ratio B of the transmittance τ(λ ₂ ) calculated by the CPU, the transmittance τ(λ ₁ ) calculated by the CPU based on the transmittance τ(λ ₂ ) and the black body spectral radiance calculated by the CPU (Λ ₂ , t)/B(λ ₁ , t) and the temperature T of the object 20 calculated by the CPU are temporarily stored.

The CPU reads the program Prog_F from the ROM, sequentially executes steps S1-1B, S1-2B, S22 to S24, S25A, S26A, S28, and S29 of the read program Prog_F, and executes the object 20 by the method described above. The temperature and/or the absolute amount or concentration of absorber ABS.

In this case, the CPU that detects the approximate value R _est of the black body spectral radiance ratio constitutes a “detection unit”, and the transmittance ratio τ(λ ₂ )/τ(λ ₃ ), the transmittance τ(λ ₂ ), τ(λ ₁ ) and the CPU that calculates the temperature T constitute “calculation means”. Further, spectral irradiances I(λ ₁ , T), I(λ ₂ , T), I(λ ₃ , T), emissivity ε(λ ₁ ), ε(λ ₂ ), ε(λ ₃ ) and absorption The CPU that receives the coefficients ε _a (λ ₁ ), ε _a (λ ₂ ), and ε _a (λ ₃ ) constitutes “reception means”.

Further, the program Prog_F may be recorded in a recording medium (for example, CD and DVD) and distributed. In this case, the computer (CPU) reads the program Prog_F from the recording medium and executes it to detect the temperature of the object 20 and/or the absolute amount or concentration of the absorber ABS. Therefore, a CD, a DVD, or the like in which the program Prog_F is recorded is a computer (CPU) readable recording medium in which the program Prog_F is recorded.

Further, in the third embodiment, the calculation unit 4B may calculate the temperature of the target object 20 according to the flowchart shown in FIG. In this case, the calculation unit 4B calculates the calculated temperature _{T est1} of the object 20 in accordance with step S21, S22, S51 of FIG. 12, also may the calculated temperature _{T est1} that the calculated as the temperature of the object 20, Fig. 12 step S21 in, S22, S51, and calculates the calculated temperature _{T est2} of object 20 according to S52, or the calculated temperature _{T est2} that the calculated as the temperature of the object 20. In this case, the operation of the calculation unit 4B may be executed by the program Prog_C described above.

[Temperature calculation accuracy]
The effect in the third embodiment will be described by using an infrared detection device in which the object 20 is in the temperature range of 0 to 100° C. and the temperature is calculated by correcting the transmittance of water vapor.
(Setting of infrared detector)
First, the infrared detector 10B is prepared in advance according to the third embodiment. Hereinafter, specific examples in the case where the absorber is water vapor will be shown. For simplicity, assume the same detection conditions as in the first and second embodiments. Further, the detection rate α is 0.1 and the emissivity ε(λ ₁ ), ε(λ ₂ ), ε(λ ₃ ) is 1.

Within the range of the window of the atmosphere shown in FIG. 3, the detection wavelength λ _{1 is selected} to be 8.5 μm, the detection wavelength λ ₂ is selected to be 13.0 μm, and the detection wavelength λ ₃ is selected to be 13.5 μm.

The brightness ratio parameter 43 and the transmittance calculation tables 42 and 45 are set in the calculator 4B. Further, the value of the brightness ratio parameter 43 is set to 0.947. For example, since the ratio of the black body spectral radiance when the temperature of the black body is 0 to 100° C. is 0.930 to 0.965, the ratio of the black body spectral radiance changes by about 3.6%.

The transmittance calculation table 42 refers to the ratio of extinction coefficients ε _a (λ ₂ )/ε _a (λ ₃ ) based on the formula (5) for calculating the transmittance from the transmittance ratio, for example, referring to FIG. And create it as 0.5. This is the ratio of the extinction coefficients of water vapor at wavelengths of 13.0 μm and 13.5 μm.

The transmittance calculation table 45 is based on the equation (24) for calculating the transmittance τ(λ ₁ ) from the transmittance τ(λ ₂ ), and the extinction coefficient ratio ε _a (λ ₁ )/ε _a (λ ₂ ) Is created as 0.37 with reference to FIG. 3, for example. This is the ratio of the extinction coefficient of water vapor at a wavelength of 8.5 μm and a wavelength of 13.0 μm.
(Calculation accuracy according to the third embodiment)
The calculation accuracy of the temperature in the third embodiment will be described based on the simulation. First, we created a simulation task. Set the transmittances τ(λ ₁ )=0.50, τ(λ ₂ )=0.25 and τ(λ ₃ )=0.77 to match the adopted extinction coefficient ratios of 0.5 and 0.37. Then, the spectral irradiances I (8.5 μm, T), I (13 μm, T), and I (13.5 μm, T) corresponding to each temperature were calculated based on the equation (1). This spectral irradiance is defined as the spectral irradiances I(λ ₁ , T), I(λ ₂ , T), I(λ ₃ , T) detected by the detectors 1 to 3, and based on the third embodiment. Then, the temperature of the object 20 was calculated.

First, from the approximate value R _est of the ratio of the spectral irradiance I (13 μm, T), I (13.5 μm, T) of the spectral irradiance and the ratio of the blackbody spectral radiance set in the brightness ratio parameter 43, The ratio of the rates was calculated based on equation (12). Then, from the ratio of the ratio of transmittance and extinction coefficient, based from equation (5) transmission based on tau (lambda ₂₎ to calculate the transmittance was the calculated tau (lambda ₂₎ in the equation (24) The transmittance τ(λ ₁ ) was calculated. Then, from the spectral irradiances I (13 μm, T), I (13.5 μm, T) and the transmittances τ(λ ₁ ), τ(λ ₂ ), the black body spectral radiance ratio B is calculated based on the equation (3). (Λ ₂ ,T)/B(λ ₁ ,T) is calculated, and the calculated ratio B(λ ₂ ,T)/B(λ ₁ ,T) of the black body spectral radiance is substituted into the equation (25). Then, the temperature of the object 20 was calculated.

FIG. 17 is a diagram showing a temperature difference between the set temperature of the target object 20 and the calculated temperature obtained by the simulation. In FIG. 17, the vertical axis represents the difference between the calculated temperature and the temperature of the target object 20, and the horizontal axis represents the temperature of the target object 20.

With reference to FIG. 17, even when the transmittance depends on the wavelength, the calculated temperature falls within an error of about −2.9° C. to +1.5° C. with respect to the temperature of the object 20. That is, assuming that the detection wavelength λ ₂ is 13.0 μm, the detection wavelength λ ₃ is 13.5 μm, and the ratio of the black body spectral radiance at these wavelengths is 0.947, the target object 20 has a temperature of 0 to 100° C. Within the temperature range, the temperature can be calculated with the accuracy of −2.9° C. to +1.5° C. by the method in the third embodiment.

[Effects of Third Embodiment]
The effect of the third embodiment will be described.
(Effects of radiation thermometer)
An effect obtained when the infrared detector 10B according to the third embodiment is used as a radiation thermometer will be described.

In the conventional monochromatic method, the temperature is calculated by setting the transmittance to a value that is predicted in advance. Therefore, if the transmittance differs from the value, a calculation error occurs in the temperature. For example, assume that a monochromatic radiation thermometer (infrared ray detection device 10B) that detects a detection wavelength of 8.5 μm is set, and that the transmittance should be set to 0.77, where 1.0 is set. That is, the radiation thermometer (infrared detector 10B) estimates the spectral radiance of the object 20 to be 0.77 times the original value. Under this condition, when the temperature of the target object 20 of 35° C. is detected according to the equation (1), the calculated temperature becomes about 21° C., which causes a large error.

Further, in the conventional two-color method, since the transmittance has wavelength dependency, it is not possible to calculate temperature with high accuracy. In the conventional two-color method, the temperature is calculated on the assumption that the transmittance does not depend on the wavelength. Therefore, when the actual transmittance has the wavelength dependency, a calculation error occurs in the temperature. For example, using a conventional two-color radiation thermometer that detects infrared rays having a detection wavelength of 8.5 μm and infrared rays having a detection wavelength of 13.0 μm, the transmittance is τ(8.5 μm)=0.77 and τ( It is assumed that the temperature of the object 20 is calculated under the condition of 13.0)=0.5. Under this condition, if the temperature is calculated by regarding the ratio of the spectral irradiance as the ratio of Planck's equation, the temperature 35° C. of the object 20 is calculated as the temperature 137° C.

On the other hand, as shown in the simulation and FIG. 17, the infrared detector 10B according to the third embodiment can accurately calculate the temperature even when the transmittance depends on the wavelength. That is, the infrared detection device 10B according to the third embodiment has a transmittance correction function not found in conventional radiation thermometers.

According to the third embodiment, by adding the detector 1 to the second embodiment, it is possible to calculate the temperature using the two-color method. That is, unlike the second embodiment in which the emissivity of the target object 20 needs to be known in advance, the third embodiment can accurately measure the temperature if the emissivity of the target object 20 does not depend on the wavelength. It can be calculated. For example, the temperature of the target object 20 is not limited to a person, an animal, a cooking utensil, a cooking tool material, or the like, and the temperature of the general outdoor target object 20, such as a person, a car, a road surface, or a tree, is calculated with high accuracy. be able to.

Further, in the third embodiment, the transmittance and the temperature can be calculated with high accuracy without being affected by the apparent emissivity due to the angle between the object 20 and the infrared detection device 10B. In other words, the infrared detection device 10B according to the third embodiment does not necessarily have to be arranged at right angles to the object 20. Therefore, the user can arbitrarily arrange the infrared detection device 10B and calculate the transmittance and the temperature. For example, by disposing the infrared detection device 10B at the corner of the room, it is possible to monitor the transmittance and the temperature of the entire room.

Furthermore, according to the third embodiment, as in the second embodiment, it is possible to calculate the temperature with the transmittance corrected. Thereby, for example, in an environment where the transmittance greatly changes due to the influence of water vapor (for example, outdoors in bad weather such as rain or fog, a bathroom, etc.), it is possible to improve the detection performance of humans or animals. That is, in bad weather, it is possible to detect a person or an animal from a farther distance, and it is possible to detect an accident in a bathroom early.

Further, according to the infrared detection device 10B of the third embodiment, the temperature is calculated with high accuracy by using the detection wavelengths λ ₁ , λ ₂ and λ ₃ whose transmittance can be reduced due to the presence of an absorber such as water vapor. be able to. For example, the outside of the range of the atmospheric window, which has been conventionally unsuitable, can be used as the detection wavelength. That is, even when the detection wavelengths λ ₁ , λ ₂ , and λ ₃ belong to ₃ to 3.5 μm, 4.5 to 8 μm, or 13 to 16 μm, the temperature and the transmittance can be calculated with high accuracy. In particular, the infrared detection device 10B according to the third embodiment uses the outside of the window of the atmosphere as the detection wavelength λ ₁ or the detection wavelength λ ₃ to increase the difference in wavelength used to calculate the ratio of the spectral radiance. Can be taken. As a result, the change in the ratio of the spectral radiance when the temperature of the object 20 changes can be further increased, and the temperature can be calculated with higher accuracy as compared with the existing two-color thermometer.

Since the absorber ABS existing between the object 20 and the infrared detection device 10B is determined by the wavelengths λ ₁ and λ ₂ , the type of the absorber ABS is inspected in advance especially in the atmosphere. No need.
(Effects on gas sensor)
The effect of using the infrared detector 10B according to the third embodiment as a gas sensor will be described.

The infrared detection device 10B according to the third embodiment can calculate the transmittance of the absorber and simultaneously calculate the absolute amount of the absorber. When the distance between the object 20 and the infrared detection device 10B is known, the concentration of the absorber can be calculated. For example, if the absorber is water vapor, the amount of water vapor and the humidity at the distance between the object 20 and the infrared detection device 10B can be calculated. The target absorber is not limited to water vapor, but may be a gas absorber such as carbon dioxide or a scatterer such as an aerosol.

According to the infrared detection device 10B according to the third embodiment, the concentration of the absorber can be calculated with high accuracy as long as the temperature of the target object 20 is within a certain range. That is, for example, as compared with a gas sensor using an infrared detector represented by Patent Document 3, the infrared detection device 10B according to the third embodiment does not require a light source as a constituent element. Therefore, in the situation where it is difficult to install the light source or the situation where it is desired to suppress the energy consumption, the calculation of the gas concentration in the infrared detection device 10B according to the third embodiment is very effective. That is, since the infrared detection device 10B can be used as a space-saving and energy-saving gas sensor, it can be used as an IoT device in which a large number of sensors need to be arranged.

Since the absorber ABS existing between the object 20 and the infrared detection device 10B is determined by the wavelengths λ ₂ and λ ₃ , the type of the absorber ABS is inspected in advance, especially in the atmosphere. No need.

The distance between the target object 20 and the infrared detection device 10B may be measured in advance if the target object 20 and the infrared detection device 10B are fixed. When the infrared detection device 10B is provided with a lens, the focal length of the lens may be the distance between the object 20 and the infrared detection device 10B.
(Effects of radiation thermometer and gas sensor)
An effect obtained when the infrared detector 10B according to the third embodiment is used as a detector having both functions of a radiation thermometer and a gas sensor will be described.

Which gas species the infrared detection device 10B according to the third embodiment detects depends on whether or not the detection wavelength has absorption. For example, with water vapor, the humidity can be calculated while measuring the temperature of the object 20 regardless of whether it is indoors or outdoors. In Patent Document 2, a hygrometer is provided, but this hygrometer measures the humidity in the vicinity of the radiation thermometer.

On the other hand, the infrared detection device 10B according to the third embodiment measures the average humidity from the object 20 to the detectors 1 to 3. Therefore, in a situation where the environment between the object 20 and the detectors 1 to 3 is significantly different, the temperature and humidity calculation by the infrared detection device 10B is very effective. That is, since the cooking utensil containing steam can be used for detecting the temperature and the amount of water vapor, the user or the cooking utensil itself can judge the cooking state and feed it back.

For example, if the gas type to be detected is carbon dioxide, the carbon dioxide concentration can be calculated while measuring the temperature of the object regardless of whether it is indoors or outdoors. Patent Document 4 is a gas sensor that detects the carbon dioxide concentration, and this gas sensor measures the carbon dioxide concentration near the installation location.

On the other hand, the infrared detection device 10B according to the third embodiment measures the average carbon dioxide concentration from the object 20 to the detectors 1 to 3. Therefore, in a situation where the environment between the object 20 and the detectors 1 to 3 is greatly different, the calculation of the temperature and the carbon dioxide concentration in the infrared detection device 10B according to the third embodiment is very effective. In other words, in the ventilation equipment and air conditioning equipment that adjust the carbon dioxide concentration, it can be used to detect the indoor and outdoor carbon dioxide concentration. You can judge and give feedback.

If the target to be detected is not an absorber such as gas but a scatterer such as aerosol, the concentration of the scatterer can be calculated while measuring the temperature of the target. That is, since it can be used for detecting scatterers in ventilation equipment, air conditioning equipment and air cleaners, the user or the ventilation equipment, air conditioning equipment and air cleaner itself can judge the state of scatterer concentration. , You can give feedback.
(Effects of radiation thermometer and gas sensor for measuring actual temperature)
Since the infrared detection device 10B according to the third embodiment can detect the temperature and the concentration of the absorber at the same time, the infrared detection device 10B can be used as a device for measuring the substantial temperature or the comfort index calculated from the temperature of the object 20 and the concentration of the absorber. It is suitable. For example, by detecting the temperature and the humidity at the same time, the substantial temperature calculated from the temperature and the humidity can be measured. The substantial temperature includes, for example, a sensible temperature, which is a temperature felt by a person, and an effective heating temperature applied to food by a cooking device. Generally, as the temperature and humidity of the object 20 increase, the substantial temperature increases.

A suitable wavelength for calculating the substantial temperature will be described. As described above, in the third embodiment, when the temperature of the target object 20 changes, the ratio of the black body spectral radiance changes slightly, so that a calculation error occurs in the temperature and the transmittance of the target object 20. That is, the accuracy of calculating the temperature and the transmittance of the object 20 depends on the accuracy of dividing the ratio of the black body spectral radiance and the ratio of the transmittance.

On the other hand, even if the difference between the temperature of the object 20 and the transmittance is accompanied by an error, the substantial temperature can be calculated with high accuracy. For example, regardless of whether the value of temperature or humidity is increased, under the condition that the ratio of the spectral irradiance increases, the calculation error due to the carving can be canceled out, so that the actual temperature must be calculated with high accuracy. You can In other words, the temperature and humidity are not sufficiently separated due to experimental error and deviation from the transmission model, and even if the humidity is calculated higher (lower) than it actually is, the temperature is calculated lower (higher), so The conversion reduces the calculation error. In other words, the substantial temperature can be calculated with high accuracy by selecting the wavelength so that the correlation between the substantial temperature and the ratio of the spectral irradiance becomes large.

Detection wavelength lambda _2, the a lambda ₃ and lambda _{2 <lambda 3} according the third embodiment, when the temperature of the object 20 is increased, by the nature of the expression of Planck, detection wavelength lambda _2, lambda ₃ of the black body spectral radiation The illuminance ratio (B(λ ₂ , T)/B(λ ₃ , T)) increases. In other words, as the temperature of the object 20 increases, the ratio of the spectral irradiance detected by the detectors 2 and 3 (I(λ ₂ , T)/I(λ ₃ , T)) increases.

Therefore, if the wavelengths λ ₂ and λ ₃ where the transmittance ratio (τ(λ ₂ )/τ(λ ₃ )) increases with respect to the increase in humidity are selected, they are detected by the detector 2 and the detector 3. The ratio of the spectral irradiance (I(λ ₂ , T)/I(λ ₃ , T)) also increases, and the substantial temperature calculation error due to the temperature/humidity separation error is reduced.

Here, a schematic diagram of the relationship between the transmittance of water vapor at a certain humidity and the wavelength is shown in FIG. In the wavelength region of 3.0 to 16 μm, the water vapor transmission rate can be classified into three types: a high transmission rate region, a first low transmission rate region, and a second low transmission rate region. The high transmittance region is a wavelength region showing a high transmittance of 3.5 to 4.5 μm and 8.0 to 13.0 μm. The first low transmittance region is a low transmittance region of 3.0 to 3.5 μm and 6.0 to 8.0 μm and a wavelength region where the transmittance increases as the wavelength becomes longer. The second low transmittance region is a low transmittance region of 4.5 to 6.0 μm and 13.0 to 16.0 μm and a wavelength region where the transmittance decreases as the wavelength becomes longer.

According to the Lambert-Beer law shown in the equation (4), there is a negative correlation between the transmittance and the extinction coefficient at the same absorber concentration. That is, the wavelength condition under which the transmittance ratio (τ(λ ₂ )/τ(λ ₃ )) increases with increasing humidity satisfies τ(λ ₂ )>τ(λ ₃ ) in FIG. Wavelength. That is, when the detection wavelength λ ₂ belongs to the high transmittance region and the detection wavelength λ ₃ belongs to the adjacent low transmittance region (that is, the second low transmittance region), and the detection wavelengths λ ₂ and λ ₃ are This is the case where they belong to the same second low transmittance region.

That is, when the detection wavelength λ ₂ is in the range of 3.5 to 4.5 μm and the detection wavelength λ ₃ is in the range of 4.5 to 6.0 μm, the substantial temperature can be calculated with high accuracy. it can. Alternatively, when the detection wavelength λ ₂ belongs to the range of 8.0 to 13.0 μm and the detection wavelength λ ₃ belongs to the range of 13.0 to 16.0 μm, the substantial temperature can be calculated with high accuracy. .. Alternatively, when the detection wavelengths λ ₂ and λ ₃ belong to the range of 4.5 to 6.0 μm, the substantial temperature can be calculated with high accuracy. Alternatively, when the detection wavelengths λ ₂ and λ ₃ belong to the range of 13.0 to 16.0 μm, the substantial temperature can be calculated with high accuracy.

Regarding the calculation of the substantial temperature, the calculation parameter for directly calculating the substantial temperature from the spectral irradiance of the detection wavelengths λ ₂ and λ ₃ is used instead of the brightness ratio parameter 43 and the transmittance calculation tables 42 and 45. It may be arranged in the calculation unit 4B.
(Effects of radiation thermometer and gas sensor for measuring comfort index)
The comfort index may be calculated based on the temperature and the carbon dioxide concentration or the temperature and the aerosol concentration, instead of the actual temperature. Thus, the user, the cooking device, the ventilation device, the air conditioning device, and the air purifier can perform feed back by making a judgment based on the substantial temperature and the index of comfort.

With respect to the comfort index that decreases when the temperature and the carbon dioxide concentration increase, a suitable wavelength will be described. Similar to the case of the substantial temperature, the condition that can reduce the error in separating the temperature of the object 20 and the transmittance is that the ratio of the transmittance (τ(λ ₂ )/τ( with respect to the increase of the carbon dioxide concentration). There are two detection wavelengths that increase λ ₃ )).

Here, a schematic diagram of the relationship between the carbon dioxide transmittance and the wavelength at a certain humidity is shown in FIG. In the case of carbon dioxide transmittance, the wavelength range of 3.0 to 16 μm can be classified into three types: a high transmittance area, a second low transmittance area, and a third low transmittance area. The high transmittance region is a wavelength region showing a high transmittance of 3.5 to 4.0 μm and 4.5 to 13.5 μm. The second low transmittance region is a low transmittance region of 13.5-16.0 μm and a wavelength region in which the transmittance decreases as the wavelength becomes longer. The third low transmittance region is a wavelength region showing a low transmittance of 4.0 to 4.5 μm.

According to the Lambert-Beer law shown in the equation (4), there is a negative correlation between the transmittance and the extinction coefficient at the same absorber concentration. That is, the wavelength condition in which the transmittance ratio (τ(λ ₂ )/τ(λ ₃ )) increases with increasing humidity satisfies τ(λ ₂ )>τ(λ ₃ ) in FIG. Wavelength. That is, when the detection wavelength λ ₂ belongs to the high transmittance region and the detection wavelength λ ₃ belongs to the adjacent low transmittance region (that is, the second low transmittance region), and the detection wavelengths λ ₂ and λ ₃ Belong to the same second low transmittance region.

That is, when the detection wavelength λ ₂ is in the range of 3.5 to 4.0 μm and the detection wavelength λ ₃ is in the range of 4.0 to 4.5 μm, the comfort index can be calculated with high accuracy. it can. Alternatively, when the detection wavelength λ ₂ belongs to the range of 4.5 to 13.5 μm and the detection wavelength λ ₃ belongs to the range of 13.5 to 16.0 μm, the comfort index can be calculated with high accuracy. .. Alternatively, when the detection wavelengths λ ₂ and λ ₃ belong to the range of 13.5 to 16.0 μm, the comfort index can be calculated with high accuracy.

Regarding the calculation of the comfort index, the brightness ratio parameter 43 and the transmittance calculation tables 42 and 45 are replaced by calculation parameters for directly calculating the comfort index from the spectral irradiance of the detection wavelengths λ ₂ and λ _3. It may be arranged in the calculation unit 4B.
(Effects of Application of Third Embodiment)
By forming the infrared detection device 10B according to the third embodiment into an array, it can be used as an infrared camera. The infrared camera to which the infrared detection device 10B according to the third embodiment is applied can simultaneously capture both an image regarding the temperature of the object 20 and an image regarding the absolute amount of the absorber. With this function, the contour and distribution of the object 20 can be determined with higher accuracy.

The other description of the third embodiment is the same as the description of the second embodiment.

In the first embodiment, the second embodiment and the third embodiment described above, the effect when the detection wavelength is set to 8.5 μm, 13.0 μm and 13.5 μm has been confirmed, but another detection wavelength may be used. It goes without saying that it has the same effect.

FIG. 18 is an infrared detection device for detecting a temperature distribution of an object and/or an absolute amount distribution or a concentration distribution of an absorber existing between the object and an infrared detector according to the embodiment of the present invention. FIG.

With reference to FIG. 18, the infrared detection device 100 includes a lens 110, detector groups 120-1 to 120-N (N is an integer of 2 or more), and a calculation unit 130.

The lens 110 focuses the infrared light emitted from the region REG_1 of the object 20 on the detector group 120-1. In addition, the lens 110 focuses the infrared light emitted from the region REG_2 of the target object 20 on the detector group 120-2. Thereafter, similarly, the lens 110 focuses the infrared rays emitted from the region REG_N of the object 20 on the detector group 120-N.

Each of the detector groups 120-1 to 120-N has, for example, a configuration in which the two detectors 1 and 2 in the first embodiment are arranged one-dimensionally or two-dimensionally. Then, the detector group 120-1 detects the spectral irradiance I _{REG_1} (λ ₁ , T), I _{REG — 1} (λ ₂ , T) of the infrared light condensed by the lens 110, and the detected spectral irradiance I. _{REG_1} (λ ₁ , T), I _{REG_1} (λ ₂ , T) is output to the calculation unit 130. Further, the detector group 120-2 detects the spectral irradiance I _{REG_2} (λ ₁ , T), I _{REG — 2} (λ ₂ , T) of the infrared light condensed by the lens 110, and the detected spectral irradiance I. _{REG_2} (λ ₁ , T) and I _{REG_2} (λ ₂ , T) are output to the calculation unit 130. Hereinafter, similarly, the detector group 120-N detects the spectral irradiances I _{REG_N} (λ ₁ ,T) and I _{REG_N} (λ ₂ ,T) of the infrared rays condensed by the lens 110, and detects them. The spectral irradiances I _{REG_N} (λ ₁ , T) and I _{REG_N} (λ ₂ , T) are output to the calculation unit 130.

The calculation unit 130 includes N calculation units 130-1 to 130-N. Calculation units 130-1 to 130-N are provided corresponding to detector groups 120-1 to 120-N, respectively. Each of the calculation units 130-1 to 130-N is, for example, the calculation unit 4 according to the first embodiment.

The calculation unit 130-1 receives the spectral irradiances I _{REG_1} (λ ₁ , T) and I _{REG — 1} (λ ₂ , T) from the detector group 120-1, and receives the received spectral irradiance I _{REG — 1} (λ ₁ , T). ), I _{REG_1} (λ ₂ , T), the temperature T _{REG_1} in the region REG_1 of the target object 20 from the region REG_1 of the target object 20 to the detector group 120-1 by the method in the first embodiment described above. Infrared transmittance τ _{REG_1} (λ ₁ ), the absolute amount ABA _{REG_1} and the concentration C _{REG_1} of the absorber ABS existing between the region REG_1 of the object 20 and the detector group 120-1 are calculated.

The calculation unit _130-2 receives the spectral irradiances I _{REG — 2} (λ ₁ , T) and I _{REG — 2} (λ ₂ , T) from the detector group 120-2, and receives the received spectral irradiance I _{REG — 2} (λ ₁ , T). ), I _{REG_2} (λ ₂ , T), the temperature T _{REG_2} in the region REG_2 of the object 20 from the region REG_2 of the object 20 to the detector group 120-2 by the method in the first embodiment described above. Infrared transmittance τ _{REG_2} (λ ₁ ), the absolute amount ABA _{REG_2} of the absorber ABS existing between the region REG_2 of the object 20 and the detector group 120-1, and the concentration C _{REG_2} are calculated.

Hereinafter, similarly, the calculation unit 130-N receives the spectral irradiances I _{REG_N} (λ ₁ , T) and I _{REG_N} (λ ₂ , T) from the detector group 120-N, and receives the received spectral irradiance I. _{Based on REG_N} (λ ₁ ,T) and I _{REG_N} (λ ₂ ,T), the temperature and temperature T _{REG_N} in the region REG_N of the target object 20 and the detector from the region REG_N of the target object 20 by the method in the first embodiment described above. Infrared transmittance τ _{REG_N} (λ ₁ ) up to the group 120-N, absolute amount ABA _{REG_N} or concentration C _{REG_N of} the absorber ABS existing between the region REG_N of the object 20 and the detector group 120-N. To calculate.

Then, the calculation unit 130 calculates the temperatures T _{REG_1 to} T _{REG_N} calculated by the calculation units 130-1 to 130-N, the transmittances τ _{REG_1} (λ ₁ ) to τ _{REG_N} (λ ₁ ), and the absorber ABS. based on the absolute amount _ABA REG_1 _{~ABA REG_N} and absorber ABS concentration _C REG_1 _{~C REG_N,} the temperature distribution and the transmittance of the object 20, the temperature and the absolute amount of the absorber ABS object 20 distribution, object At least one of the distribution of the temperature of 20 and the concentration of the absorber ABS and the distribution of the temperature and emissivity of the object 20 is calculated. Here, the distribution of the temperature and the emissivity of the target object 20 is calculated using the known emissivity of the target object 20.

In the infrared detection device 100, each of the detector groups 120-1 to 120-N has a configuration in which the two detectors 2 and 3 according to the second embodiment are arranged one-dimensionally or two-dimensionally, and the calculation unit 130. Each of −1 to 130-N may be configured by the calculation unit 4A, and each of the detector groups 120-1 to 120-N has one of the three detectors 1 to 3 in the third embodiment in one dimension or two. Each of the calculation units 130-1 to 130-N may be composed of the calculation unit 4B. In such a case, the calculation unit 130 (calculation units 130-1 to 130-N) uses the method according to the above-described second or third embodiment to distribute the temperature and the transmittance of the target object 20, the target object 20. At least one of the distribution of the temperature and the absolute amount of the absorber ABS, the distribution of the temperature of the object 20 and the concentration of the absorbent ABS, and the distribution of the temperature and the emissivity of the object 20 are calculated.

Further, the calculation unit 130 does not have to include N calculation units 130-1 to 130-N. In this case, the calculator 130 receives the spectral irradiances I _{REG_1} (λ ₁ , T), I _{REG — 1} (λ ₂ , T), and the spectral irradiance I _{REG — 2} (λ) received from the detector groups 120-1 to ₁₂₀ -N, respectively. ₁ , T), I _{REG — 2} (λ ₂ , T),..., Spectral irradiance I _{REG — N} (λ ₁ , T), I _{REG — N} (λ ₂ , T) on the basis of the method and implementation in the first embodiment Of the object 20 and the transmittance of the object 20, the temperature of the object 20 and the distribution of the absolute amount of the absorber ABS, and the temperature of the object 20 using the method according to the second embodiment or the method according to the third embodiment. At least one of the distribution of the concentration of the absorber ABS and the distribution of the temperature and the emissivity of the object 20 is calculated.

Furthermore, the operation of the calculation unit 130 (calculation units 130-1 to 130-N) may be executed by any of the programs Prog_A to Prog_F described above.

As described above, by using the infrared detection device 100, the distribution of the temperature and the transmittance of the target object 20, the temperature of the target object 20 and the distribution of the absolute amount of the absorber ABS, the temperature of the target object 20 and the concentration of the absorber ABS. And at least one of the temperature and the emissivity distribution of the object 20 can be calculated.

FIG. 19 is a flow chart for explaining the operation of the infrared detection device 100 shown in FIG.

With reference to FIG. 19, when the operation of the infrared detection device 100 is started, the detector group 120-1 and the calculation unit 130-1 are the flowchart shown in FIG. 2, the flowchart shown in FIG. Either of the _above , the temperature T _{REG_1 of the} object 20, the transmittance τ _{REG_1} , the absolute amount ABA _{REG_1} of the absorber ABS, and the concentration C _{REG_1} of the absorber ABS are calculated (step S101-1).

In addition, the detector group 120-2 and the calculation unit _130-2 are configured such that the temperature T _{REG_2} , the transmittance τ _{REG_2 of} the target object 20, and the flowchart shown in FIG. 9, the flowchart shown in FIG. 9, and the flowchart shown in FIG. The absolute amount ABA _{REG_2} of the absorber ABS and the concentration C _{REG_2} of the absorber ABS are calculated (step S101-2).

In the same manner, a detector group 120-N and the calculation section 130-N is, the flow chart shown in FIG. 2, the temperature _{T REG_N} object 20 by any of the flowcharts shown in the flowchart and 16 shown in FIG. 9, the transmission The rate τ _{REG_N} , the absolute amount ABA _{REG_N} of the absorber ABS and the concentration C _{REG_N} of the absorber ABS are calculated (step S101-N).

Then, the calculation unit 130 is based on the temperatures T _{REG_1 to} T _{REG_N} of the object 20, the transmittance τ _{REG_1 to} τ _{REG_N} , the absolute amount ABA _{REG_1 to} ABA _{REG_N} of the absorber ABS, and the concentrations C _{REG_1 to} C _{REG_N} of the absorber ABS. The distribution of the temperature and the transmittance of the object 20, the temperature of the object 20 and the distribution of the absolute amount of the absorber ABS, the distribution of the temperature of the object 20 and the concentration of the absorber ABS, the temperature of the object 20 and the emissivity At least one of the distributions is calculated (step S102).

As a result, the operation of the infrared detection device 100 ends.

When the flowchart shown in FIG. 2 is used in each of steps S101-1 to S101-N, each of the calculation units 130-1 to 130-N has a spectral irradiance I(λ ₁ , detected by the detector ₁ . T) and the spectral irradiance I(λ ₂ , T) detected by the detector 2 based on the spectral irradiance ratio I(λ ₁ , T)/I(λ ₂ , T), the transmittance ratio τ( λ ₁ )/τ(λ ₂ ) is calculated, the transmittance τ(λ ₁ ) is calculated based on the calculated transmittance ratio τ(λ ₁ )/τ(λ ₂ ), and the calculated transmittance The temperature of the object 20, the absolute amount of the absorber ABS, and the concentration are calculated based on τ(λ ₁ ).

Therefore, the calculation units 130-1 to 130-N perform the steps S101-1 to S101-N based on the spectral irradiance ratio I(λ ₁ , T)/I(λ ₂ , T) to determine the transmittance ratio τ. The process of calculating (λ ₁ )/τ(λ ₂ ) is executed for N sets of spectral irradiance ratios I(λ ₁ , T), I(λ ₂ , T) detected by the N detector groups. Te calculated ratio of N transmittance tau a _{(λ 1) / τ (λ} 2), the ratio τ (λ ₁₎ of the N transmission / τ (λ ₂₎ N pieces of transmission based on tau (Λ ₁ ) is calculated, and N temperatures in N regions REG_1 to REG_N of the object 20 and N regions REG_1 to REG_N of the object 20 are calculated based on the N transmittances τ(λ ₁ ). The absolute number of N and the concentration of the absorber ABS existing between the detector groups 120-1 to 120-N are calculated.

Further, in each of steps S101-1 to S101-N, when the flowchart shown in FIG. 9 or the flowchart shown in FIG. 16 is used, each of the calculation units 130-1 to 130-N is detected by the detector 2. Spectral irradiance ratio I(λ ₂ , T)/I(λ ₃ , T) of the spectral irradiance I(λ ₂ , T) and the spectral irradiance I(λ ₃ , T) detected by the detector 3 and The transmittance ratio τ(λ ₂ )/τ(λ ₃ ) is calculated based on the approximate value R _est of the black body spectral radiance ratio, and the calculated transmittance ratio τ(λ ₂ )/τ(λ ₃ ) The transmittance τ(λ ₂ ) is calculated based on the calculated transmittance τ(λ ₂ ) and the temperature of the object 20, the absolute amount of the absorber ABS, and the concentration are calculated based on the calculated transmittance τ(λ ₂ ).

Therefore, the calculation units 130-1 to 130-N perform step S101-1 to S101-N based on the spectral irradiance ratio I(λ ₂ , T)/I(λ ₃ , T) and the approximate value R _est. The process of calculating the transmittance ratio τ(λ ₂ )/τ(λ ₃ ) is performed by N sets of spectral irradiance ratios I(λ ₂ , T), I(λ ₃ , T) was performed for calculating the ratio of N transmittance _{τ (λ 2) / τ (} λ 3), the ratio tau (lambda ₂ of N _{transmittance)} / τ (λ ₃₎ on the basis of N The transmittances τ(λ ₂ ) of N objects are calculated, and the N temperatures of the regions REG_1 to REG_N of the target object 20 and the N values of the target object 20 are calculated based on the N transmittances τ(λ ₂ ). The N absolute amounts and the N concentrations of the absorber ABS existing between the regions REG_1 to REG_N and the detector groups 120-1 to 120-N are calculated.

In the infrared detection device 100, the operation of detecting the temperature of the object 20 and/or the absolute amount or concentration of the absorber ABS may be executed by software. In this case, each of the calculation units 130-1 to 130-N includes a CPU, a ROM and a RAM.

The ROM stores any of the programs Prog_A, Prog_B, and Prog_F described above. The other description is the same as the description about the programs Prog_A, Prog_B, and Prog_F described above.

In the first embodiment described above, first, the transmittance ratio τ(λ ₁ )/τ(λ ₂ ) is calculated based on the measured spectral irradiances I(λ ₁ , T) and I(λ ₂ , T). It has been described that (or τ(λ ₂ )/τ(λ ₁ )) is calculated. Then, the ratio of the calculated transmittance _{τ (λ 1) / τ (} λ 2) ( or _{τ (λ 2) / τ (} λ 1)) transmittance tau (lambda ₁₎ from (or tau (lambda ₂₎ ) Is calculated. Finally, it has been described that the temperature of the object 20 and/or the absolute amount or concentration of the absorber ABS is calculated based on the calculated transmittance τ(λ ₁ ) (or τ(λ ₂ )).

In the second embodiment described above, first, the infrared spectral irradiances I(λ ₂ , T), I(λ ₃ , T) having wavelengths λ ₂ , λ ₃ longer than the peak wavelength λ _max , The transmittance ratio τ(λ ₂ )/τ(λ ₃ ) (or τ(λ ₃ )/τ(λ ₂ )) is calculated based on the approximate value R _est of the ratio of the blackbody spectral radiance. explained. Next, from the calculated transmittance ratio τ(λ ₁ )/τ(λ ₂ )(or τ(λ ₃ )/τ(λ ₂ )), the transmittance τ(λ ₂ ) (or τ(λ ₃ ) ) Is calculated. Finally, it has been described that the temperature of the object 20 and/or the absolute amount or concentration of the absorber ABS is calculated based on the calculated transmittance τ(λ ₁ ) (or τ(λ ₃ )).

Further, in the above-described third embodiment, first, infrared spectral irradiances I(λ ₂ , T), I(λ ₃ , T) having wavelengths λ ₂ , λ ₃ longer than the peak wavelength λ _max , The transmittance ratio τ(λ ₂ )/τ(λ ₃ ) (or τ(λ ₃ )/τ(λ ₂ )) is calculated based on the approximate value R _est of the ratio of the blackbody spectral radiance. explained. Next, from the calculated transmittance ratio τ(λ ₁ )/τ(λ ₂ )(or τ(λ ₃ )/τ(λ ₂ )), the transmittance τ(λ ₂ ) (or τ(λ ₃ ) ) Is calculated. Finally, on the basis of the transmittance the calculated τ (λ ₁₎ (or τ (λ ₃₎₎ transmittance τ (λ ₁₎ is calculated from the transmittance that the calculated τ (λ _1), the object 20 Of temperature and/or calculating the absolute amount or concentration of absorber ABS.

As described above, the first to third embodiments calculate the ratio of transmittances at two wavelengths based on the two spectral irradiances at the two wavelengths, and calculate one wavelength from the calculated ratios of transmittances. Is calculated, and the temperature of the object 20 and/or the absolute amount or concentration of the absorber ABS is calculated based on the calculated transmittance at one wavelength.

Therefore, according to the embodiment of the present invention, the infrared detection device detects at least one of the temperature of the object, the absolute amount of the absorber existing between the object and the infrared detector, and the concentration of the absorber. An infrared detection device for detecting, comprising a first detector for detecting a first spectral irradiance of a first infrared ray having a first wavelength, and a second detector having a second wavelength longer than the first wavelength. A second detector for detecting a second spectral irradiance of infrared rays of No. 2 and a first spectral irradiance ratio which is a ratio of the first spectral irradiance to the second spectral irradiance; The first transmittance, which is the transmittance of the first infrared ray between the object and the first and second detectors, and the transmission of the second infrared ray between the object and the first and second detectors. A first transmittance ratio, which is a ratio with the second transmittance that is a ratio, is calculated, and one of the first and second transmittances is calculated based on the calculated first transmittance ratio. And a calculation unit that calculates at least one of the temperature of the object, the absolute amount of the absorber, and the concentration of the absorber based on the calculated third transmittance. Just do it.

Further, according to the embodiment of the present invention, the infrared detection method determines at least one of the temperature of the object, the absolute amount of the absorber existing between the target and the infrared detector, and the concentration of the absorber. A detection method for detecting, comprising a first spectral irradiance of a first infrared ray having a first wavelength and a second spectral irradiance of a second infrared ray having a second wavelength longer than the first wavelength. The first and second infrared rays from the object based on the first step of detecting the illuminance and the first spectral irradiance ratio which is the ratio of the first spectral irradiance and the second spectral irradiance. Is the ratio of the first transmittance, which is the first infrared transmittance between the detector and the detector, to the second transmittance, which is the second infrared transmittance between the object and the detector. A second step of calculating the first transmittance ratio and a third transmittance which is one of the first transmittance and the second transmittance based on the calculated first transmittance ratio. A third step of calculating and a fourth step of calculating at least one of the temperature of the object, the absolute amount of the absorber and the concentration of the absorber based on the calculated third transmittance. Good.

Further, according to the embodiment of the present invention, the program causes the computer to detect at least one of the temperature of the object, the absolute amount of the absorber existing between the object and the infrared detector, and the concentration of the absorber. And a second infrared ray having a second wavelength longer than the first wavelength, the first spectral irradiance of the first infrared ray having the first wavelength, and the second infrared ray having a second wavelength longer than the first wavelength. The second spectral irradiance of the first spectral irradiance, and the calculation means based on the first spectral irradiance ratio, which is a ratio of the first spectral irradiance and the second spectral irradiance. A first transmittance that is a first infrared transmittance between the object and the first and second infrared detectors, and a second transmittance that is a second infrared transmittance between the object and the detector. A second step of calculating a first transmittance ratio, which is a ratio with the transmittance of 2; and a calculating means, based on the calculated first transmittance ratio, one of the first and second transmittances. The third step of calculating the third transmittance, which is one of the transmittances, and the calculating means calculates the temperature of the target object, the absolute amount of the absorber, and the concentration of the absorber based on the calculated third transmittance. The computer may be caused to execute the fourth step of calculating at least one.

The embodiments disclosed this time are to be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the claims, and is intended to include meanings equivalent to the claims and all modifications within the scope.

The present invention is applied to an infrared detection device, an infrared detection method, a program to be executed by a computer, and a computer-readable recording medium recording the program.

1 to 3 detector, 4, 4A, 4B, 130, 130-1 to 130-N calculation unit, 1010A, 10B, 100 infrared detection device, 20 object, 41 luminance table, 42, 45 transmittance calculation table , 43 luminance ratio parameter, 44 wavelength selection unit, 46 emissivity calculation table, 110 lens, 120-1 to 120-N detector group.

Claims (26)

An infrared detection device for detecting at least one of a temperature of an object, an absolute amount of an absorber existing between the object and an infrared detector, and a concentration of the absorber,
A first detector for detecting a first spectral irradiance of a first infrared having a first wavelength;
A second detector for detecting a second spectral irradiance of a second infrared ray having a second wavelength longer than the first wavelength;
Based on a first spectral irradiance ratio, which is a ratio of the first spectral irradiance and the second spectral irradiance, the first to second detectors from the object to the first and second detectors. The ratio of the first transmittance, which is the transmittance of infrared rays of 1, and the second transmittance, which is the transmittance of the second infrared rays between the object and the first and second detectors. A certain first transmittance ratio is calculated, and a third transmittance that is either one of the first transmittance and the second transmittance is calculated based on the first transmittance ratio. An infrared detection device comprising: a calculator that calculates at least one of the temperature of the object, the absolute amount of the absorber, and the concentration of the absorber based on the transmittance of No. 3. The calculation unit uses the relationship between the infrared transmittance and the black body spectral radiance and the spectral irradiance, and based on the third transmittance, the temperature of the object, the absolute amount of the absorber, and the The infrared detection device according to claim 1, which calculates at least one of the concentrations of the absorbers. The calculation unit uses a detection ratio, which is a ratio detected by the first and second detectors, of the spectral radiance emitted by the object, and an emissivity of the first infrared ray from the object. Based on a certain first emissivity, the third transmittance, and the first spectral irradiance, a first black body spectral radiance that is a black body spectral radiance at the first wavelength is obtained. The infrared ray according to claim 2, wherein at least one of the temperature of the object, the absolute amount of the absorber, and the concentration of the absorber is calculated based on the calculated first black body spectral radiance. Detection device. The calculation unit includes a first parameter that is a ratio of an absorption coefficient of the first infrared ray and an absorption coefficient of the second infrared ray between the object and the first and second detectors, The third transmittance is calculated based on the first transmittance ratio using the relationship between the first transmittance ratio and the third transmittance. The infrared detection device according to claim 1. The calculator further calculates the temperature of the object and the concentration of water vapor existing between the object and the detector based on the third transmittance, and calculates the concentration of the water vapor and Calculate the substantial temperature from the temperature of the object,
The first wavelength is set in the range of 3.5 to 6.0 μm, and the second wavelength is set in the range of 4.5 to 6.0 μm,
Or
The first wavelength is set in the range of 3.5 to 4.5 μm, and the second wavelength is set in the range of 6.0 to 8.0 μm,
Or
The first wavelength is set in the range of 3.5 to 4.5 μm, and the second wavelength is set in the range of 13.0 to 16.0 μm,
Or
The first wavelength is set in a range of 8.0 to 16.0 μm, and the second wavelength is set in a range of 13.0 to 16.0 μm. Infrared detection device given in any 1 paragraph. The calculation unit further calculates the temperature of the target object and the concentration of carbon dioxide existing between the target object and the detector based on the third transmittance, Calculate an index of comfort from the concentration and the temperature of the object,
The first wavelength is set in the range of 3.5 to 4.0 μm, and the second wavelength is set in the range of 4.0 to 4.5 μm,
Or
The first wavelength is set in a range of 3.5 to 4.0 μm, and the second wavelength is set in a range of 13.5-16.0 μm,
Or
The first wavelength is set in a range of 4.5 to 16.0 μm, and the second wavelength is set in a range of 13.5-16.0 μm. Infrared detection device given in any 1 paragraph. The calculation unit calculates a first black body spectral radiance that is a black body spectral radiance at the first wavelength and a second black body spectral radiance that is a black body spectral radiance at the second wavelength. The infrared detection device according to any one of claims 1 to 4, wherein the first transmittance ratio is calculated based on the first spectral irradiance ratio using an approximate value of the ratio. Further comprising a third detector for detecting a third spectral irradiance of a third infrared having a third wavelength shorter than the first wavelength,
The calculation unit calculates a first black body spectral radiance that is a black body spectral radiance at the first wavelength and a second black body spectral radiance that is a black body spectral radiance at the second wavelength. The first transmittance ratio is calculated based on the first spectral irradiance ratio using an approximate value of the ratio, the third transmittance is calculated from the first transmittance ratio, and the target object is calculated. The fourth transmittance, which is the transmittance of the third infrared ray between the first to the second detectors and the third to the third detectors, is calculated from the third transmittance, and the fourth transmittance is calculated as follows. The infrared detection device according to claim 1, wherein at least one of the temperature of the object, the absolute amount of the absorber, and the concentration of the absorber is calculated based on the third transmittance. The infrared detection device according to claim 7 or 8, wherein the first and second wavelengths are longer than a peak wavelength at which a maximum value of the black body spectral radiance is obtained. The calculation unit is a second ratio that is a ratio between the absorption coefficient of the first infrared ray and the absorption coefficient of the third infrared ray between the object and the first, second, and third detectors. The infrared detection device according to claim 8, wherein the fourth transmittance is calculated from the third transmittance using a relationship among a parameter, the third transmittance, and the fourth transmittance. .. The calculation unit is a second transmittance ratio which is a ratio of the third transmittance and the fourth transmittance, and a ratio of the first spectral irradiance and the third spectral irradiance. A second spectral irradiance ratio, and a first emissivity that is the emissivity of the object at the first wavelength and a second emissivity that is the emissivity of the object at the third wavelength. A first blackbody spectral radiance that is a blackbody spectral radiance at the first wavelength and a second blackbody that is a blackbody spectral radiance at the third wavelength based on an emissivity ratio that is a ratio. The black body spectral radiance ratio, which is the ratio to the spectral radiance, is calculated, and the temperature of the object, the absolute amount of the absorber, and the absorption are calculated based on the relationship between the calculated black body spectral radiance ratio and temperature. The infrared detection device according to claim 8 or 10, which calculates at least one of the body concentrations. The calculator further calculates the temperature of the object and the concentration of water vapor existing between the object and the detector based on the third transmittance, and calculates the concentration of the water vapor and Calculate the substantial temperature from the temperature of the object,
The first wavelength is set in the range of 3.5 to 6.0 μm, and the second wavelength is set in the range of 4.5 to 6.0 μm,
Or
The said 1st wavelength is set to the range of 8.0-16.0 micrometers, and the said 2nd wavelength is set to the range of 13.0-16.0 micrometers. Infrared detection device given in any 1 paragraph. The calculation unit further calculates the temperature of the target object and the concentration of carbon dioxide existing between the target object and the detector based on the third transmittance, Calculate the comfort index from the concentration and the temperature of the object,
The first wavelength is set in the range of 3.5 to 4.0 μm, and the second wavelength is set in the range of 4.0 to 4.5 μm,
Or
The said 1st wavelength is set to the range of 4.5-16.0 micrometers, and the said 2nd wavelength is set to the range of 13.5-16.0 micrometers. Infrared detection device given in any 1 paragraph. Two or three detectors among the first to third detectors are one detector of quantum well type or quantum dot type,
The infrared detection device controls a voltage applied to the one detector to control a wavelength of infrared light to be detected to be two wavelengths or three wavelengths of the first to third wavelengths. The infrared detection device according to claim 8, further comprising: The first and second detectors arranged in an array form a detector group,
The calculation unit performs a process of calculating the first transmittance ratio based on the first spectral irradiance ratio, and a plurality of sets of the first and second spectral radiation detected by the plurality of detector groups. The plurality of first transmittance ratios are calculated by executing the illuminance, the plurality of third transmittances are calculated based on the plurality of first transmittance ratios, and the plurality of third transmittances are calculated. The infrared detection device according to claim 1, wherein a plurality of temperatures in a plurality of regions of the target object are calculated based on, and a temperature distribution of the target object is calculated based on the calculated plurality of temperatures. The first to third detectors arranged in an array form a detector group,
The calculation unit executes a process of calculating the first transmittance ratio based on the first spectral irradiance ratio using the approximate value for a plurality of the first spectral irradiance ratios, and performs a plurality of processes. The first transmittance ratio is calculated, the plurality of third transmittances are calculated from the plurality of first transmittance ratios, and the plurality of fourth transmittances are calculated as the plurality of third transmittances. Calculated based on the plurality of third transmittances and the plurality of fourth transmittances, a plurality of temperatures in a plurality of regions of the target object are calculated, and the target based on the calculated plurality of temperatures. The infrared detection device according to claim 8, which calculates a temperature distribution of an object. An infrared detection method for detecting at least one of a temperature of an object, an absolute amount of an absorber existing between the object and an infrared detector, and a concentration of the absorber,
First to detect a first spectral irradiance of a first infrared ray having a first wavelength and a second spectral irradiance of a second infrared ray having a second wavelength longer than the first wavelength Steps of
Based on a first spectral irradiance ratio, which is a ratio of the first spectral irradiance and the second spectral irradiance, between the object and the detectors of the first and second infrared rays. A first ratio that is a ratio of a first transmittance that is the transmittance of the first infrared ray and a second transmittance that is the transmittance of the second infrared ray between the object and the detector. A second step of calculating the transmittance ratio,
A third step of calculating a third transmittance which is either one of the first and second transmittances based on the calculated first transmittance ratio;
A fourth step of calculating at least one of the temperature of the object, the absolute amount of the absorber, and the concentration of the absorber based on the calculated third transmittance. In the second step, the first transmittance ratio is a first blackbody spectral radiance that is a blackbody spectral radiance at the first wavelength and a blackbody spectral radiance at the second wavelength. 18. The infrared detection method according to claim 17, which is calculated based on the first spectral irradiance ratio using an approximate value of a ratio with a certain second black body spectral radiance. A fourth transmittance, which is a transmittance of a third infrared ray having a third wavelength shorter than the first wavelength between the object and the detector, is calculated from the third transmittance. 5 steps are further provided,
In the first step, further detecting a third spectral irradiance of the third infrared,
In the second step, the first transmittance ratio is a first blackbody spectral radiance that is a blackbody spectral radiance at the first wavelength and a blackbody spectral radiance at the second wavelength. Is calculated based on the first spectral irradiance ratio using an approximate value of a ratio with a certain second black body spectral radiance,
In the fourth step, at least one of the temperature of the object, the absolute amount of the absorber, and the concentration of the absorber is calculated based on the third transmittance and the fourth transmittance. The infrared detection method according to claim 17. In the second step, the first transmittance ratio is calculated from the first spectral irradiance and the peak wavelength at the first wavelength longer than the peak wavelength at which the maximum value of the black body spectral radiance is obtained. 20. The infrared detection method according to claim 19, which is calculated based on the second spectral irradiance at the second wavelength that is also long. In the fourth step, at least one of the temperature of the object, the absolute amount of the absorber, and the concentration of the absorber is a ratio of the third transmittance and the fourth transmittance. A transmittance ratio of 2, a second spectral irradiance ratio that is a ratio of the first spectral irradiance and the third spectral irradiance, and an emissivity of the object at the first wavelength. Black body spectral radiance at the first wavelength calculated based on an emissivity ratio that is a ratio between the emissivity of 1 and the second emissivity of the object at the third wavelength. 20. The calculation is performed based on the relationship between the ratio of the first black body spectral radiance that is ##EQU1## and the second black body spectral radiance that is the black body spectral radiance at the third wavelength and the temperature. Infrared detection method described in. The first detector for detecting the first infrared ray and the second detector for detecting the second infrared ray are arranged in an array to form a detector group,
In the first step, each of the plurality of detector groups detects the first and second spectral irradiances,
In the second step, a process of calculating the first transmittance ratio based on the first and second spectral irradiances is executed for a plurality of sets of the first and second spectral irradiances, and a plurality of processes are performed. Calculating the first transmittance ratio of
In the third step, calculating a plurality of the third transmittance based on the plurality of first transmittance ratios,
In the fourth step, a plurality of temperatures in a plurality of regions of the object are calculated based on the plurality of third transmittances, and a temperature distribution of the object is calculated based on the calculated plurality of temperatures. The infrared detection method according to claim 17, wherein A first detector for detecting the first infrared ray, a second detector for detecting the second infrared ray, and a third detector for detecting the third infrared ray are arranged and arranged in an array. A group of vessels,
In the first step, each of the plurality of detector groups detects the first to third spectral irradiances,
In the second step, a process of calculating the first transmittance ratio based on the first spectral irradiance ratio using the approximation value is performed for a plurality of sets of the first and second spectral irradiances. Executing to calculate a plurality of the first transmittance ratios,
In the third step, calculating a plurality of the third transmittance based on the plurality of first transmittance ratios,
In the fifth step, calculating the plurality of fourth transmittances from the plurality of third transmittances,
In the fourth step, a plurality of temperatures in a plurality of regions of the object are calculated based on the plurality of third transmittances and the plurality of fourth transmittances, and based on the calculated plurality of temperatures. 20. The infrared detection method according to claim 19, wherein the temperature distribution of the target is calculated. A program for causing a computer to detect at least one of a temperature of an object, an absolute amount of an absorber existing between the object and an infrared detector, and a concentration of the absorber,
The reception means sets the first spectral irradiance of the first infrared ray having the first wavelength and the second spectral irradiance of the second infrared ray having the second wavelength longer than the first wavelength. The first step of accepting,
The calculating means detects the first and second infrared rays from the object on the basis of a first spectral irradiance ratio which is a ratio of the first spectral irradiance and the second spectral irradiance. Between the first transmittance, which is the transmittance of the first infrared ray during the period up to, and the second transmittance, which is the transmittance of the second infrared ray between the object and the detector. A second step of calculating a certain first transmittance ratio;
A third step in which the calculating means calculates a third transmittance, which is one of the first and second transmittances, based on the calculated first transmittance ratio;
The computer executes a fourth step of calculating at least one of the temperature of the object, the absolute amount of the absorber, and the concentration of the absorber based on the calculated third transmittance. A program to let you. In the second step, the calculating means calculates a first black body spectral radiance that is a black body spectral radiance at the first wavelength and a second black body spectral radiance at the second wavelength. The program for causing a computer to execute according to claim 24, wherein the first transmittance ratio is calculated based on the first spectral irradiance ratio using an approximate value of a ratio with a black body spectral radiance. A computer-readable recording medium in which the program according to claim 24 or 25 is recorded.

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