Measurement device and measurement method

Abstract

Provided are a measurement device and a measurement method with which it is possible to measure a volatile component with high accuracy. A measurement device (1) is provided with: a vaporizing chamber (21) in which a sample (S) containing a target component is placed; a measurement chamber (23) which is spatially connected to the vaporizing chamber (21) and which integrally forms a sealed space with the vaporizing chamber (21); a light source (31) that irradiates the measurement chamber (23) with laser light (R) having a varying wavelength; a detection unit (51) that detects the laser light (R) irradiated from the light source (31) and passed through the measurement chamber (23); and a calculation unit (60) that analyzes the light reception signal of the laser light (R) detected by the detection unit (51) and calculates the amount of the target component contained in the sample (S), the calculation unit (60) acquiring the amount of the target component on the basis of an integrated value of the spectrum of the absorbance of the laser light (R) absorbed by the target component while the laser light (R) passes through the inside of the measurement chamber (23).

Description

[0001] Cross-references of related applications

[0002] This application claims the priority of Tokugan Application No. 2023-123851 filed in Japan on July 28, 2023, and the entire disclosure of the prior application is incorporated herein by reference. Technical Field

[0003] The present invention relates to a measuring device and a measuring method. Background Art

[0004] With the development of space development technology, it is known to measure the content or concentration of volatile components other than water present in samples such as surface rock fragments on the lunar surface. For example, it is known to collect surface rock fragments on the lunar surface, heat them to vaporize the components to be measured, measure the vaporized components, and measure the volatile components other than water (Non-Patent Document 1). In addition, sometimes the surface of the moon becomes an extremely low temperature state, and in most cases the water in the surface rock fragments exists as a solid (ice). Water that exists as a solid in an extremely low temperature state sometimes sublimates in response to heating. Therefore, in this specification, "gasification" refers to a process that includes both sublimation from a solid to a gas, and evaporation from a liquid to a gas.

[0005] Non-Patent Literature 1: Takuma Shimomura, 12 others, "Lunar Polar Probe Project: Development Status of Water Resource Analyzer", Proceedings of the 66th Joint Space Science and Technology Conference, Japan Aerospace Society, 2022 (Takuma Shimomura, 12 others, "Lunar Polar Probe Project: Development Status of Water Resource Analyzer", Proceedings of the 66th Joint Space Science and Technology Conference, Japan Aerospace Society, 2022.)

[0007] However, in the current volatile component measurement technology, there is room for improvement in measurement accuracy. Summary of the invention

[0008] An object of the present invention is to measure volatile components with high accuracy.

[0009] Regarding the measuring devices according to some embodiments,

[0010] (1) having: a vaporization chamber in which a sample containing a target component is placed;

[0011] a measuring chamber connected to the vaporizing chamber in space and integrally forming a closed space with the vaporizing chamber;

[0012] a light source for irradiating laser light of varying wavelengths to the measurement chamber;

[0013] a detection unit that detects the laser light irradiated from the light source and passed through the measurement chamber; and

[0014] a calculation unit that analyzes the light reception signal of the laser light detected by the detection unit and calculates the amount of the target component contained in the sample,

[0015] The calculation unit acquires the amount of the target component based on an integrated value of a spectrum of absorbance of the laser light absorbed by the target component while the laser light passes through the interior of the measurement chamber.

[0016] In this way, the measuring device obtains the amount of the target component based on the integrated value of the absorbance spectrum calculated according to the intensity of the laser after being absorbed by the target component while the laser passes through the inside of the measuring chamber. Therefore, even if the pressure in the closed space fluctuates greatly, the amount of the target component can be measured with high precision.

[0017] In one embodiment.

[0018] (2) The measuring device of (1), wherein:

[0019] The calculation unit may perform curve fitting on the absorbance spectrum of the laser light to a model formula to acquire curve data, and acquire an integral value of the spectrum based on the curve data.

[0020] In this way, the measuring device performs curve fitting on the absorbance spectrum of the laser light to the model formula to obtain the integrated value (area) of the spectrum, and thus can measure the absorbance spectrum of the target component with high accuracy.

[0021] In one embodiment,

[0022] (3) The measuring device according to (1) or (2), wherein:

[0023] The light source may be a wavelength-variable semiconductor laser capable of changing the wavelength of the laser light to be output.

[0024] As described above, the measuring device uses a wavelength variable semiconductor laser as a light source, thereby being able to scan the wavelength in a range including the central wavelength of the absorption line of the target component and measure the amount of the target component based on the integrated value of the spectrum.

[0025] In one embodiment,

[0026] (4) The measuring device according to any one of (1) to (3), wherein:

[0027] The light source may emit light having a periodically changing wavelength as the laser light.

[0028] The calculation unit acquires the spectrum for each of a plurality of cycles in which the wavelength of the laser light changes, and acquires the amount of the target component based on the plurality of spectra.

[0029] In this way, the measuring device acquires a spectrum for each of the multiple cycles of the laser wavelength change and acquires the amount of the target component based on the multiple spectra, thereby suppressing the influence of fluctuations in data for each cycle and measuring the amount of the target component with higher accuracy.

[0030] In one embodiment,

[0031] (5) The measuring device according to any one of (1) to (4), wherein:

[0032] The method may further include a heater for controlling the temperature of the sample.

[0033] The calculation unit outputs relationship data indicating a correspondence relationship between the temperature of the sample and the amount of the target component calculated by analyzing the light reception signal of the laser beam.

[0034] In this way, the measuring device outputs the relationship data indicating the correspondence between the temperature of the sample and the amount of the target component, and thus the binding state of the target component of the sample can be analyzed based on the relationship data.

[0035] Regarding the measurement methods involved in some embodiments,

[0036] (6) The following steps are included:

[0037] irradiating a measurement chamber which is spatially connected to a vaporization chamber in which a sample containing a target component is placed and which forms a closed space integrally with the vaporization chamber with a laser beam having a variable wavelength using a light source;

[0038] detecting, by a detection unit, the laser light emitted from the light source and passing through the measurement chamber; and

[0039] The light receiving signal of the laser beam detected by the detection unit is analyzed, and the amount of the target component contained in the sample is calculated by a calculation unit.

[0040] The calculation unit acquires the amount of the target component based on an integrated value of a spectrum of absorbance of the laser light absorbed by the target component while the laser light passes through the interior of the measurement chamber.

[0041] In this way, the measuring device obtains the amount of the target component based on the integrated value of the absorbance spectrum calculated according to the intensity of the laser after being absorbed by the target component while the laser passes through the inside of the measuring chamber. Therefore, even if the pressure in the closed space fluctuates greatly, the amount of the target component can be measured with high precision.

[0042] In one embodiment,

[0043] (7) Based on the determination method of (6), wherein

[0044] The calculation unit may perform curve fitting on the absorbance spectrum of the laser light to a model formula to acquire curve data, and acquire an integral value of the spectrum based on the curve data.

[0045] In this way, the measuring device performs curve fitting on the absorbance spectrum of the laser light to the model formula to obtain the integrated value (area) of the spectrum, and thus can measure the absorbance spectrum of the target component with high accuracy.

[0046] In one embodiment,

[0047] (8) The method of (6) or (7), wherein:

[0048] The light source may be a wavelength-variable semiconductor laser capable of changing the wavelength of the laser light to be output.

[0049] As described above, the measuring device uses a wavelength-variable semiconductor laser as a light source, thereby being able to scan the wavelength in a range including the central wavelength of the absorption line of the target component and measure the amount of the target component based on the integrated value of the spectrum.

[0050] In one embodiment,

[0051] (9) The method according to any one of (6) to (8), wherein:

[0052] The light source may emit light having a periodically changing wavelength as the laser.

[0053] The calculation unit acquires the spectrum for each of a plurality of cycles in which the wavelength of the laser light changes, and acquires the amount of the target component based on the plurality of spectra.

[0054] In this way, the measuring device acquires a spectrum for each of the multiple cycles of the laser wavelength change and acquires the amount of the target component based on the multiple spectra, thereby suppressing the influence of fluctuations in data for each cycle and measuring the amount of the target component with higher accuracy.

[0055] In one embodiment,

[0056] (10) The method according to any one of (6) to (9), wherein:

[0057] The method may further include a heater for controlling the temperature of the sample.

[0058] The calculation unit outputs relationship data indicating a correspondence relationship between the temperature of the sample and the amount of the target component calculated by analyzing the light reception signal of the laser beam.

[0059] In this way, the measuring device outputs the relationship data indicating the correspondence between the temperature of the sample and the amount of the target component, and thus the binding state of the target component of the sample can be analyzed based on the relationship data.

[0060] Effects of the Invention

[0061] According to one embodiment of the present invention, volatile components can be measured with high accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] Figure 1 It is a diagram showing the structure of a measuring device according to a comparative example.

[0063] Figure 2 This is a diagram showing an example of a graph illustrating the relationship between the water concentration and the internal pressure when the gas component is only water.

[0064] Figure 3 This is a diagram showing an example of a graph of pressure changes in a spectrum showing the absorbance of water vapor.

[0065] Figure 4 Yes Figure 3 FIG. 1 is an enlarged view of a portion of a graph.

[0066] Figure 5 This is a diagram showing an example of a graph showing the relationship between the height of a spectrum showing absorbance and the water content.

[0067] Figure 6 It is a diagram showing a configuration example of a measuring device according to one embodiment.

[0068] Figure 7 Yes means Figure 6 Flowchart of an example of the operation of a measuring device.

[0069] Figure 8 This is a diagram schematically showing the change of laser driving current over time.

[0070] Fig. 9 This is a diagram schematically showing a graph showing the relationship between the driving current and the wavelength of the laser.

[0071] Fig.10 It is a diagram schematically showing the change over time in the intensity of the light-receiving signal of the detection unit.

[0072] Fig.11 This is a diagram schematically showing the relationship between the laser wavelength and the intensity of the received light signal.

[0073] Fig.12 This is a diagram schematically showing the relationship between the laser wavelength and the intensity of the light receiving signal after baseline processing.

[0074] Fig.13 This is a diagram schematically showing the relationship between laser wavelength and absorbance.

[0075] Fig.14 This is a diagram schematically showing the relationship between the height and area of ​​the absorbance spectrum and the amount of the target component.

[0076] Fig.15 This is a diagram showing an example of relationship data indicating the relationship between temperature and the amount of target component. DETAILED DESCRIPTION

[0077] <Comparative Example>

[0078] Figure 1 : is a diagram showing the structure of a measuring device 9 involved in a comparative example. The measuring device 9 is a device for measuring the amount of target components such as water contained in a sample of solid matter such as surface rock cuttings. The measuring device 9 seals the sample in a closed space, heats the sample, and vaporizes the target component contained in the sample. The measuring device 9 irradiates the volatile gas with a laser having a single wavelength selected in accordance with the wavelength absorbed by the target component. The measuring device 9 measures the absorbance of the volatile gas, and measures the amount of the target component based on the height (value) of the absorbance.

[0079] The measuring device 9 includes a light source 91, a detector 92, and a measuring chamber 93. The measuring chamber 93 provides a closed space in which a gas 94 containing a target component vaporized from a sample exists. The light source 91 irradiates the measuring chamber 93 with laser light (incident light). The detector 92 detects the laser light (transmitted light) irradiated from the light source 91 and passing through the measuring chamber 93. The measuring device 9 is assumed to be used in an environment where there is no atmosphere, such as the surface of the moon. There is no gas component other than the gas 94 vaporized from the sample in the measuring chamber 93.

[0080] about Figure 1 In such a structure, after the measuring device 9 introduces the sample such as the surface rock cuttings of the measuring object into the measuring chamber 93, it makes the measuring chamber 93 into a closed space, and then heats the sample to vaporize the target component from the sample. The following is an example in which the target component is water. In the presence of gas vaporized from the target component, the light source 91 outputs a laser with a specific single wavelength that is known to be absorbed by the target component. The measuring device 9 measures the intensity I0 of the laser output from the light source 91 and the intensity I0 of the laser after passing through the measuring chamber 93 detected by the detector 92. t The absorbance H = ln(I0 / I t). Here, ln is a logarithmic function with the natural logarithm e as the base.

[0081] In this case, it is known that the concentration C of the gas of the target component is proportional to the absorbance H and inversely proportional to the optical path length L (Lambert-Beer law). The optical path length L is the length of the space where the laser light traverses through the gas 94 in the measuring chamber 93. If the absorption coefficient inherent to the molecules of the target component is ε, the Lambert-Beer law is expressed by the following equation 1.

[0082] (Formula 1)

[0083] C=H / εL

[0084] =ln(I0 / I t ) / εL

[0085] Therefore, as a device, the optical path length L is measured in advance, and the corresponding relationship between the absorbance value and the concentration measured by introducing a gas with a known concentration of the target component is measured, and the absorption coefficient ε is obtained in advance, so that the measuring device 9 can measure the gas concentration based on the measured absorbance. If the mass of the sample such as the surface rock chips introduced here is known, the measuring device 9 can calculate the water concentration in the surface rock chips.

[0086] However, as the concentration of the target component increases, the pressure in the measurement chamber 93 increases, and the absorbance and concentration are not exactly proportional to each other. Therefore, this pressure increase may become a factor of error in the measured value of the target component. Figure 2 to Figure 5 The influence of the pressure in the measurement chamber 93 will be described.

[0087] Figure 2 FIG. 1 is a diagram showing an example of a graph showing the relationship between water concentration and internal pressure when it is assumed that the volatile component is only water. Figure 2 In the figure, the horizontal axis is the concentration of target components such as water in the measuring chamber 93. The vertical axis is the pressure in the measuring chamber 93. Graph 901 shows that if the target component vaporizes in the measuring chamber 93 as a closed space, the internal pressure increases in proportion to the vaporization amount. Consider the case of measuring the amount of water in the surface rock debris of the actual lunar surface. For example, consider collecting 0.1g of surface rock debris and measuring the water content in the concentration range of 0.01wt% to 10wt% by this method. In this case, for example, if the temperature is 50°C and the internal volume is 150cm 3 When water as a target component is vaporized in the sealed space of the measuring chamber 93, the pressure in the measuring chamber 93 changes within the range of approximately 0.01 kPa to 10 kPa.

[0088] Figure 3 This is a diagram showing an example of a graph of pressure changes in a spectrum showing the absorbance of water vapor. Figure 4 Yes Figure 3 A portion of the graph of FIG. Figure 3 and Figure 4 In the graph 91, the horizontal axis represents the wavelength of the laser irradiated from the light source 91. The vertical axis represents the absorbance of the light absorbed by the target component in the measuring chamber 93. Graph 911 represents the spectrum of the absorbance of water vapor at 0.001 kPa. Graph 912b represents the spectrum of water vapor at 0.01 kPa. Graph 913 represents the spectrum of water vapor at 0.1 kPa. Graph 914 represents the spectrum of water vapor at 1 kPa. Graph 915 represents the spectrum of water vapor at 10 kPa. Generally, the spectrum in the near-infrared-infrared range of target components such as water vapor is generated due to the interaction between light absorbed based on molecular vibration and molecules. As shown in graphs 911 to 915, the shape of the spectrum (Line shape) is represented by the Voigt function composed of the convolution of the Gaussian distribution function as a diffusion based on the Doppler effect and the Lorentz distribution function as a diffusion based on molecular collision. Graphs 911 to 915 show the spectrum of water vapor at a predetermined wavelength at intervals of one digit for a pressure range of 0.001 kPa to 10 kPa at a concentration of 100%. Graphs 911 to 915 are based on data from the HITRAN database (https: / / hitran.org / ).

[0089] The shape of the absorbance spectrum is deformed due to the pressure dissimilarity. As a result, the height of the peak of the spectrum changes nonlinearly with respect to the amount of water in the regolith. Figure 5 FIG. 1 is a diagram showing an example of a graph showing the relationship between the height of a spectrum showing absorbance and the amount of water. Figure 5 In FIG. 1 , the horizontal axis represents the amount of the target component in the measuring chamber 93. Here, the amount of the target component is proportional to the concentration of the target component. The vertical axis represents the peak height of the spectrum. Figure 5 In the graph 921, the curve shape is convex upward. In this way, the height of the spectrum changes nonlinearly with respect to the amount of water in the surface rock cuttings. Therefore, if the amount of the target component is measured as a value proportional to the height of the spectrum, the measured value of the amount contains an error. In other words, in order to accurately measure the amount of the target component based on the height of the spectrum, that is, the measured value of the absorbance relative to a single wavelength of laser light, pressure correction based on a complex calibration curve is required.

[0090] As described above, if the content of the target component after heating and vaporization is to be measured in a wide range based on the peak height of the absorbance spectrum, the pressure in the closed space increases due to the gas components in the closed space, and the pressure varies in a wide range depending on the amount of the target component. As a result, there is room for improvement in the measurement accuracy of the measuring device 9 according to the comparative example.

[0091] <Implementation Method>

[0092] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. In each of the drawings, the same reference numerals are given to parts having the same structure or function. In the description of this embodiment, repeated descriptions of the same parts may be appropriately omitted or simplified.

[0093] The present invention aims to accurately measure the content of each target component by using spectral data of the absorbance of the measured gas even in a wide range of pressure environments where the target component is volatilized by heating a sample in a closed space. In addition, the present invention aims to slowly increase the heating temperature at a predetermined rate by using the accurate measurement capability under the wide range of concentrations and pressures to obtain the relationship data between the temperature and the amount of the target component. The relationship data has a shape corresponding to the binding state of the target component with respect to the sample, and can therefore be used to analyze the existence state of the target component in the sample.

[0094] Figure 6 : This is a diagram showing a structural example of a measuring device 1 involved in one embodiment. The measuring device 1 measures the amount of target components such as water contained in a sample S such as surface rock debris based on variable wavelength semiconductor laser absorption spectroscopy (TDLAS). Below, an example is described in which the measuring device 1 measures the amount of water (including ice) contained in sandy surface rock debris in an ultra-high vacuum atmosphere environment such as the lunar surface. In this environment, when the sample S is introduced into a closed space, it is isolated from the outside after the introduction, so that a closed space in an ultra-high vacuum state without gas components can be created.

[0095] like Figure 6 As shown, the measuring device 1 includes an inlet 11, a vaporization chamber 21, a conduit 22, a measuring chamber 23, a light emitting unit 33, a light receiving unit 52, and a computing unit 60. The measuring device 1 includes a window 41 between the light emitting unit 33 and the measuring chamber 23. The measuring device 1 includes a window 42 between the measuring chamber 23 and the light receiving unit 52.

[0096] The introduction port 11 is an entrance for introducing a sample S such as surface rock cuttings into the interior of the measuring device 1. The introduction port 11 is spatially connected to the vaporization chamber 21. The user can introduce the sample S into the vaporization chamber 21 from the introduction port 11. The introduction port 11 has a valve 12 for isolating the space from the outside. After the sample S is introduced, the valve 12 is closed, thereby enabling a continuous space composed of the vaporization chamber 21, the conduit 22, and the measuring chamber 23 to be sealed.

[0097] The vaporization chamber 21 places a sample S. The vaporization chamber 21 includes a heater 24. The heater 24 heats the sample S and controls the temperature thereof, thereby vaporizing a target component contained in the sample S.

[0098] The conduit 22 spatially connects the vaporization chamber 21 and the measurement chamber 23. The target component vaporized in the vaporization chamber 21 diffuses through the conduit 22 into the closed space constituted by the vaporization chamber 21, the conduit 22, and the measurement chamber 23.

[0099] The measurement chamber 23 is a space in which the vaporized target component is irradiated with laser light R and the absorbance is measured.

[0100] The light emitting unit 33 outputs laser light R to the measuring chamber 23. The light emitting unit 33 includes a light source 31 and an optical system 32. The light source 31 is a source of the laser light R. The light source 31 may be, for example, a wavelength-variable semiconductor laser capable of changing the wavelength of the laser light R. The optical system 32 includes optical elements such as lenses.

[0101] The laser light R outputted from the light emitting unit 33 passes through the measurement chamber 23 via the window 41 , and is partially absorbed by the target component. The laser light R passing through the measurement chamber 23 reaches the light receiving unit 52 via the window 42 .

[0102] The light receiving unit 52 includes a detection unit 51. When the detection unit 51 detects the laser light R, it outputs an electrical signal corresponding to the light intensity thereof as a light receiving signal to the calculation unit 60. The detection unit 51 can be, for example, a photodiode having a photoelectric conversion function. The detection unit 51 is electrically connected to the calculation unit 60.

[0103] The operation unit 60 analyzes the light receiving signal received from the light receiving unit 52 and calculates the amount of the target component contained in the sample S. The operation unit 60 has a control unit 61, a storage unit 62 and an input-output unit 63. The control unit 61 has more than or equal to one processor and controls the operation of the operation unit 60. The storage unit 62 stores data including measurement data and programs. The storage unit 62 can have, for example, RAM (Random Access Memory), ROM (Read Only Memory) and storage (such as SSD (Solid State Drive), hard disk, etc.). The input-output unit 63 accepts operation input from the user or displays the operation result of the operation unit 60 to the user. The input-output unit 63 can have an input device and a display device. For example, the input-output unit 63 can have a keyboard, a pointing device or a touch panel as an input device. The input-output unit 63 can have a liquid crystal panel or an organic EL (electro-luminescence) display as an output device.

[0104] With the above-described configuration, the measuring device 1 acquires the amount of the target component based on the integral value of the absorbance obtained from the intensity of the laser light R absorbed by the target component during the period when the laser light R passes through the inside of the measuring chamber 23. Specifically, the measuring device 1 analyzes the light receiving signal, acquires the spectrum of the absorbance of the laser light R absorbed by the target component during the period when the laser light R passes through the inside of the measuring chamber 23, and acquires the amount of the target component based on the integral value of the spectrum of the absorbance. Therefore, according to the measuring device 1, even if the target component is vaporized in a closed space and the pressure in the measuring chamber 23 changes significantly, the amount of the target component can be measured with high accuracy.

[0105] Figure 7 Yes means Figure 6 Flow chart of an example of the operation of the measuring device 1. Figure 7 The described action of the measuring device 1 may be equivalent to one of the measuring methods of the measuring device 1. As a prerequisite for performing the following actions, the measuring device 1 is set to an ultra-high vacuum state (ultra-low pressure state) at a low temperature at which ice has not vaporized, similar to the surface of the moon. In the initial state, the valve 12 of the measuring device 1 is open. The heater 24 is in the OFF state. The vaporization chamber 21 is open to the outside, and the heater is also in the OFF state, so it is at a low temperature at which ice has not vaporized, and is in the same ultra-high vacuum state (ultra-low pressure state) as the surface of the moon. The following actions begin before the sample S is introduced into the vaporization chamber 21.

[0106] In step S1, the measuring device 1 starts output of laser light R from the light source 31 and light reception by the detection unit 51. In the present embodiment, the measuring device 1 operates before introducing the sample S into the vaporization chamber 21 and starts measuring the absorbance spectrum of water as the target component.

[0107] In step S2 , the measuring device 1 accepts the user's introduction of a sample S. Specifically, the user introduces the sample S such as surface rock chips from the introduction port 11 into the vaporization chamber 21 , closes the valve 12 , and forms a sealed space formed by the vaporization chamber 21 , the conduit 22 , and the measuring chamber 23 .

[0108] In step S3, the measuring device 1 heats the sample S using the heater 24 and controls the temperature of the sample S to a desired value. As a result, the water as the target component inside the sample S is vaporized, and the ice is also vaporized. The water diffuses to the measuring chamber 23 through the conduit 22. The vaporization chamber 21, the conduit 22, and the measuring chamber 23 constitute a closed space, so the concentration of the target component in the measuring chamber 23 increases in accordance with the vaporization of the target component within a range that does not exceed the saturated vapor pressure. In this process, the measuring device 1 continuously uses the light emitting unit 33 and the light receiving unit 52 to measure the absorbance spectrum of the target component.

[0109] In step S4, the measurement device 1 acquires a light reception signal of the laser light R that has passed through the space containing the target component in the measurement chamber 23. Specifically, the detection unit 51 outputs a signal indicating the intensity of the detected laser light R to the calculation unit 60 as a light reception signal.

[0110] In step S5, the measuring device 1 acquires the amount of the target component based on the area value (integrated value) of the absorbance spectrum calculated from the intensity of the laser light R absorbed by the target component. The process of acquiring the amount of the target component will be described in detail later.

[0111] In step S6, the measuring device 1 outputs the amount of the target component obtained in step S5. Specifically, the measuring device 1 stores the measured value of the amount of the target component in the storage unit 62, or displays it on the input and output unit 63. If the processing of step S6 is completed, the measuring device 1 ends the processing of the flowchart. After this action, the measuring device 1 stops the heating of the heater 24 and cools it. The user opens the valve 12 and discharges the sample S, so that the enclosed space in the measuring device 1 is open to the outside. As a result, the vaporization chamber 21 and the measuring chamber 23 are quickly restored to an ultra-high vacuum state. In the case of a sample S of other measurement objects, the user can measure the target component contained in the sample S.

[0112] Next, refer to Figure 8 to Figure 13 The process of acquiring the amount of the target component in step S5 will be described in detail.

[0113] Figure 8 is a diagram schematically showing the change of laser drive current over time. Figure 8 In FIG. 78 , the horizontal axis represents time. The vertical axis represents the magnitude of the laser driving current for driving the light source 31. The curve 781 represents the change of the laser driving current over time. Figure 8 In the example of FIG. 7 , graph 781 indicates that the drive current varies between i0 and i2 with a period t0.

[0114] Fig. 9 FIG. 2 is a diagram schematically showing a graph showing the relationship between the driving current of a laser and the wavelength. Fig. 9In the graph, the horizontal axis represents the magnitude of the laser driving current for driving the light source 31. The vertical axis represents the wavelength of the laser R output from the light source 31. Graph 801 represents the relationship between the laser driving current and the wavelength when the temperature T of the light source 31 is 20 degrees. Graph 802 represents the relationship between the laser driving current and the wavelength when the temperature T of the light source 31 is 25 degrees. Graph 803 represents the relationship between the laser driving current and the wavelength when the temperature T of the light source 31 is 30 degrees. As shown in graphs 801 to 803, at a certain temperature, the magnitude of the laser driving current and the wavelength form a linear relationship with each other. Moreover, at a certain laser driving current, the wavelength of the laser R tends to increase in accordance with the increase in temperature. Therefore, the measuring device 1 is pre-controlled so that the wavelength of the laser R output from the light source 31 becomes the central wavelength λ1 of the absorption line of a specific wavelength possessed by the water vapor of the target component. Specifically, as shown in graphs 801 to 803, Fig. 9 As shown in FIG. 1 , the oscillation wavelength of the semiconductor laser shifts according to the temperature. Therefore, the measuring device 1 controls the temperature of the light source 31 to a temperature corresponding to the absorption line center wavelength λ1 in advance. Fig. 9 In the example, when the laser driving current varies between i0 and i2, at temperature T = 25 degrees, the wavelength of the laser R output from the light source 31 varies within the range of λ0 to λ2 including the absorption line center wavelength λ1 of the target component.

[0115] like Figure 8 As shown in the curve graph 781, the laser driving current changes periodically with a period t0, such as Fig. 9 As shown in Figure 1, the laser driving current has a linear relationship with the wavelength of the laser R. Therefore, when the laser driving current is Figure 8 When the wavelength of the laser light R changes as shown in the graph 781 of FIG. 78A , the wavelength of the laser light R also changes periodically. In other words, the light source 31 outputs the laser light R having a wavelength scanned within a range including the central wavelength λ1 of the absorption line of the light absorbed by the target component.

[0116] Fig.10 Schematically shows the change in the intensity of the light-receiving signal of the detection unit 51 over time. Fig.10 In the figure, the horizontal axis represents time and the vertical axis represents the intensity of the light-receiving signal. Fig.10 In FIG. 782, the curve 782 shows that the intensity of the received light signal varies within the range of I0 to I2 with a period t0. Figure 8Compared with the shape of the graph 781 of FIG. 782, the light receiving signal intensity of the graph 782 does not increase linearly, but has a shape having a concave portion 783 in a portion. The concave portion 783 indicates that the laser light R is absorbed by the target component at the absorption wavelength of the target component while passing through the measurement chamber 23. As described later, in this embodiment, the measurement device 1 converts the light receiving signal intensity into absorbance, calculates the area (integral value) of the spectrum of the absorbance, and obtains the amount of the target component.

[0117] Regarding the calculation of the area of ​​the portion corresponding to the recess 783, refer to Figure 11 to Figure 13 Provide explanation. Fig.11 is a diagram schematically showing the relationship between the laser wavelength and the intensity of the light-receiving signal. Fig.11 In FIG. 81 , the horizontal axis represents the wavelength of the laser R. The vertical axis represents the intensity of the light-receiving signal detected by the detection unit 51. The curve 811 represents the relationship between the wavelength of the laser R and the intensity of the light-receiving signal in a certain period of the periodically changing laser R. As mentioned above, the wavelength of the laser R is proportional to the laser driving current ( Fig. 9 ), in a certain cycle, the laser driving current is Figure 8 That forms a linear relationship with time. Therefore, Fig.11 The wavelength is the value corresponding to time in a linear relationship in a cycle with a swept wavelength. Fig.11 In the example of , the graph 811 has a concave portion near the absorption line center wavelength λ1. The area of ​​the concave portion is related to Fig.10 Therefore, the measuring device 1 obtains the asymptote 812 of the graph 811 and the area 813 surrounded by the graph 811, converts it into absorbance, and calculates the area of ​​the portion corresponding to the area 813. Specifically, the measuring device 1 first calculates the difference in the intensity of the light-receiving signal between the asymptote 812 and the graph 811 for each wavelength in the wavelength range of λ0 to λ1, and performs baseline processing on the light-receiving signal.

[0118] Fig.12 Schematically shows the relationship between the laser wavelength and the intensity of the received light signal after baseline processing. Fig.12 In FIG. 821 , the horizontal axis represents the wavelength of the laser R. The vertical axis represents the intensity of the light-receiving signal detected by the detection unit 51. Fig.11 The asymptote (baseline signal) 822 represents the curve of the baseline processing of the curve graph 811. Fig.11 The asymptote 812 of the curve is processed by baseline. The area 823 is Fig.11 corresponds to area 813.

[0119] Fig.13 is a diagram schematically showing the relationship between laser wavelength and absorbance. Fig.13In FIG. 1 , the horizontal axis represents the wavelength of the laser R. The vertical axis represents the absorbance of the laser R. Fig.12 The graph 821 is converted into absorbance to obtain a graph 831. That is, the measuring device 1 compares the intensity I0 of the laser light R output from the light source 31 with the intensity I0 of the laser light R after passing through the measuring chamber 23 detected by the detection unit 51. t The absorbance H = ln(I0 / I t ).

[0120] The graph 831 has a shape represented by the aforementioned Voigt function. It can be seen that the area A of the region 841 surrounded by the graph 831 and the horizontal axis is proportional to the concentration C of the target component, the optical path length L of the laser, and the pressure P. Here, the area A is equivalent to the value obtained by integrating the absorbance spectrum represented by the graph 831 by the wavelength. The pressure P is the pressure in the closed space caused by the generation of all volatile gases including the target component. That is, if the proportionality coefficient is set to k, the concentration C of the target component is calculated based on the area A, the optical path length L of the laser, and the pressure P by the following formula 2.

[0121] (Formula 2)

[0122] C = k × A / (L × P)

[0123] If the volume of the closed space formed by the vaporization chamber 21, the conduit 22, and the measurement chamber 23 is represented by V, the molar amount M of the target component in the closed space is calculated by the following formula 3.

[0124] (Formula 3)

[0125] M=C×P×V=(k×A×V) / L

[0126] Therefore, for the target component of known amount M, the area A is calculated under the conditions of known optical path length L of the laser and volume V, thereby the proportionality coefficient k can be calculated in advance. The measuring device 1 stores such proportionality coefficient k, volume V and optical path length L in the storage unit 62 in advance. If the area A of the spectrum of the absorbance of the laser R is calculated, the measuring device 1 can obtain the total amount (amount) of the target component volatilized from the sample S based on equation 3.

[0127] Fig.14 This is a graph that uses the HITRAN database to calculate the relationship between the height and area of ​​the spectrum of absorbance of water (gas) at a certain wavelength in a closed space and the amount of the target component (water in this example). Fig.14In FIG. 8 , the horizontal axis represents the amount of the target component. The vertical axis represents the height or area of ​​the absorbance spectrum. Graph 851 represents the relationship between the area of ​​the absorbance spectrum and the amount of the target component. Graph 921 represents the relationship between the peak height of the absorbance spectrum and the amount of the target component. Fig.14 Graphs 851 and 921 show that the pressure increases as the amount of the target component increases due to the closed space, and in this example, the pressure is in the range of 0.001k to 10kPa. As shown in graph 921, the spectral peak height changes nonlinearly with respect to the component amount in the high pressure region. In contrast, as shown in graph 851, the spectral area (integrated value) changes linearly with respect to the component amount in the entire pressure region. Therefore, the measuring device 1 can use Formula 3 and the spectral area (integrated value) to measure the amount of the target component in the sample S with high accuracy within a large range of pressure and target component amount.

[0128] Furthermore, when water is measured as the target component, when the main component of the volatile components contained in the sample S is not water, that is, even when the sample S contains more components than water, the area value (integral value) of the water vapor absorbance spectrum remains linear with respect to the target component amount (amount of water). In other words, it is known that even when the target component is a substance other than water and there are volatile components other than the target component in the closed space, the amount of the target component and the area of ​​the absorbance spectrum are in a linear relationship within a wide pressure range regardless of the amount of the substance other than the target component. Therefore, even when the sample S contains components other than the target component of interest, the measuring device 1 can measure the amount of the target component with high accuracy.

[0129] The measuring device 1 can be used to measure the Fig.13 The curve graph 831 is integrated to find the area of ​​the absorbance spectrum (e.g. Fig.13 The area of ​​region 841 may be calculated by other methods. For example, the measuring device 1 may focus on the fact that the spectrum of the absorbance has the shape of a Voigt function, perform curve fitting of the graph 831 to a model formula such as a Voigt function, and use the data fitted to the complete Voigt function to calculate the area. In addition, the measuring device 1 may calculate the area of ​​the spectrum within the allowable error range, not for the entire wavelength region that forms the spectrum, but for a portion of the region centered on the peak wavelength of the spectrum. By performing the above-mentioned processing, the measuring device 1 can measure the spectrum of the object component with higher accuracy and can calculate the amount of the object component more accurately. In addition, if it is within the allowable error range, the measuring device 1 may calculate the area (integral value) of a portion of the spectrum centered on the peak wavelength of the spectrum, not for the entire wavelength region of the spectrum of the absorbance.

[0130] In addition, the measuring device 1 can be used not only to calculate the amount of the target component contained in the sample S, but also to determine the binding state of the target component contained in the sample S. For example, water exists in the sample S as free water, and can also exist as bound water, surface attached water, or internal water. The above water is the same as a molecule, but the temperature at which it vaporizes is different depending on the binding state. Therefore, the relationship between the temperature of the sample S and the amount of water molecules vaporized from the sample S and existing in the closed space represents the distribution of the binding state of water in the sample S. That is, the binding state of the original solid sample S and the volatile component of the target component can be analyzed based on the relationship data between the temperature and the volatilization amount. Therefore, the measuring device 1 can heat the sample S using the heater 24 in the closed space, and slowly increase the temperature of the sample S at a certain rate of increase, while measuring the amount of the target component as the vaporized volatile component. The measuring device 1 can output the relationship data representing the corresponding relationship between the temperature of the sample S and the amount of the target component calculated by analyzing the light receiving signal of the laser R.

[0131] Fig.15 FIG. 1 is a diagram showing an example of relationship data showing the relationship between temperature and the amount of a target component. Fig.15 In FIG. 861 , the horizontal axis represents temperature. The vertical axis represents the amount of the target component. The curve graph 861 is relationship data showing the relationship between temperature and the amount of the target component. The user can analyze the bonding state between the original solid sample S and the volatilized target component based on the temperature at which the amount of the target component increases sharply and the amount of increase.

[0132] In addition, the measuring device 1 of this embodiment can also measure the amount of target components attached to the sample S with high accuracy by irradiating target components other than water with light of a wavelength absorbed by the target components. For example, the measuring device 1 can measure carbon monoxide, carbon dioxide, oxygen, ammonia, and other components contained in the sample S as target components.

[0133] As described above, the measuring device 1 includes the vaporization chamber 21, the measuring chamber 23, the light source 31, the detection unit 51, and the computing unit 60. The vaporization chamber 21 carries the sample S containing the target component. The measuring chamber 23 is spatially connected to the vaporization chamber 21, and forms a closed space integrally with the vaporization chamber 21. The light source 31 irradiates the measuring chamber 23 with the laser light R of varying wavelength. The detection unit 51 detects the laser light R irradiated from the light source 31 and passing through the measuring chamber 23. The computing unit 60 analyzes the light receiving signal of the laser light R detected by the detection unit 51, and calculates the amount of the target component contained in the sample S. Here, the computing unit 60 obtains the amount of the target component based on the area value (integral value) of the absorbance spectrum calculated from the laser light R absorbed by the target component while the laser light R passes through the inside of the measuring chamber 23. Therefore, according to the measuring device 1, even if the pressure of the closed space changes greatly, the amount of the target component can be measured with high accuracy.

[0134] Furthermore, the calculation unit 60 may perform curve fitting on the absorbance spectrum of the laser light R to a model expression such as a Voigt function to obtain curve data, and obtain the area of ​​the spectrum based on the curve data.

[0135] In this way, the measuring device 1 performs curve fitting on the spectrum of the absorbance of the laser light R to acquire the area of ​​the spectrum, so that the calculation cost can be reduced and the amount of the target component can be output at a high speed.

[0136] In addition, the light source 31 may be a wavelength-variable semiconductor laser that can change the wavelength of the output laser light R. In this way, the measuring device 1 can use a wavelength-variable semiconductor laser as the light source 31, thereby being able to perform wavelength scanning in a range including the absorption line center wavelength λ1 of the target component and measure the amount of the target component based on the area of ​​the spectrum.

[0137] In addition, the light source 31 may irradiate light whose wavelength changes periodically as the laser light R. The operation unit 60 may acquire a spectrum for each of a plurality of cycles of wavelength change of the laser light R, and acquire the amount of the target component based on the plurality of spectra. In this way, the measuring device 1 can acquire a spectrum for each of a plurality of cycles of wavelength change of the laser light R, and acquire the amount of the target component based on the plurality of spectra, thereby suppressing the influence of fluctuations in data for each cycle, and can measure the amount of the target component with higher accuracy.

[0138] In addition, the measuring device 1 may further include a heater 24 for controlling the temperature of the sample S. The computing unit 60 may output relationship data indicating the correspondence between the temperature of the sample S and the amount of the target component calculated by analyzing the light receiving signal of the laser R. In this way, the measuring device 1 outputs the relationship data indicating the correspondence between the temperature of the sample S and the amount of the target component, and thus the binding state of the target component of the sample S can be analyzed based on the relationship data.

[0139] The present invention is not limited to the above-mentioned embodiments. For example, multiple modules recorded in the block diagram may be integrated, or one module may be divided. Multiple steps recorded in the flow chart may be executed in parallel or in different orders according to the processing capacity of the device executing each step or as needed, instead of the manner of executing in time series according to the description. In addition, changes may be made within the scope of the main purpose of the present invention.

[0140] Description of the label

[0141] 1. Measurement device

[0142] 11. Import port

[0143] 12 valves

[0144] 21 Vaporization Chamber

[0145] 22 Catheter

[0146] 23. Measurement Room

[0147] 24 Heater

[0148] 31 Light Source

[0149] 32 Lens

[0150] 33. Luminous part

[0151] 41, 42 Windows

[0152] 51 Testing Department

[0153] 52 Light receiving part

[0154] 60 Operation unit

[0155] 61 Control Department

[0156] 62 Storage

[0157] 63 Input and output unit

[0158] 781, 782 curve graph

[0159] 783 recess

[0160] 801~803 curve graph

[0161] 811, 812 curve graph

[0162] 821, 822 curve graph

[0163] 831 Graph

[0164] 841 Area

[0165] 851 Graph

[0166] 861 Graph

[0167] 9 Measurement device

[0168] 91 Light Source

[0169] 92 Detector

[0170] 93 Measurement Room

[0171] 94 Gas

[0172] 901, 911~915, 921 curve graph

[0173] S specimen

Claims

1. A measuring device, wherein: The measuring device comprises: a vaporization chamber in which a sample containing a target component is placed; a measuring chamber connected to the vaporizing chamber in space and integrally forming a closed space with the vaporizing chamber; a light source for irradiating laser light of varying wavelengths to the measurement chamber; a detection unit that detects the laser light irradiated from the light source and passed through the measurement chamber; and a calculation unit that analyzes the light reception signal of the laser light detected by the detection unit and calculates the amount of the target component contained in the sample, The calculation unit acquires the amount of the target component based on an integrated value of a spectrum of absorbance of the laser light absorbed by the target component while the laser light passes through the interior of the measurement chamber.

2. The measuring device according to claim 1, wherein The calculation unit performs curve fitting on the absorbance spectrum of the laser light to a model formula to acquire curve data, and acquires an integral value of the spectrum based on the curve data.

3. The measuring device according to claim 1 or 2, wherein: The light source is a wavelength-variable semiconductor laser capable of changing the wavelength of the laser light to be output.

4. The measuring device according to any one of claims 1 to 3, wherein The light source irradiates light having a periodically changing wavelength as the laser light. The calculation unit acquires the spectrum for each of a plurality of cycles in which the wavelength of the laser light changes, and acquires the amount of the target component based on the plurality of spectra.

5. The measuring device according to any one of claims 1 to 4, wherein The measuring device further comprises a heater for controlling the temperature of the sample. The calculation unit outputs relationship data indicating a correspondence relationship between the temperature of the sample and the amount of the target component calculated by analyzing the light reception signal of the laser beam.

6. A measuring method for a measuring device, wherein: The measuring method comprises the following steps: irradiating a measurement chamber which is spatially connected to a vaporization chamber in which a sample containing a target component is placed and which forms a closed space integrally with the vaporization chamber with a laser beam having a variable wavelength using a light source; detecting, by a detection unit, the laser light emitted from the light source and passing through the measurement chamber; and The light receiving signal of the laser beam detected by the detection unit is analyzed, and the amount of the target component contained in the sample is calculated by a calculation unit. The calculation unit acquires the amount of the target component based on an integrated value of a spectrum of absorbance of the laser light absorbed by the target component while the laser light passes through the interior of the measurement chamber.

7. The assay method according to claim 6, wherein The calculation unit performs curve fitting on the absorbance spectrum of the laser light to a model formula to acquire curve data, and acquires an integral value of the spectrum based on the curve data.

8. The assay method according to claim 6 or 7, wherein The light source is a wavelength-variable semiconductor laser capable of changing the wavelength of the laser light to be output.

9. The assay method according to any one of claims 6 to 8, wherein The light source irradiates light having a periodically changing wavelength as the laser light. The calculation unit acquires the spectrum for each of a plurality of cycles in which the wavelength of the laser light changes, and acquires the amount of the target component based on the plurality of spectra.

10. The assay method according to any one of claims 6 to 9, wherein The method further comprises the step of controlling the temperature of the sample by a heater, The calculation unit outputs relationship data indicating a correspondence relationship between the temperature of the sample and the amount of the target component calculated by analyzing the light reception signal of the laser beam.

Images