WO2015132986A1

WO2015132986A1 - Breath diagnosis device

Info

Publication number: WO2015132986A1
Application number: PCT/JP2014/073936
Authority: WO
Inventors: 康友塩見; 茂行高木; 努角野; 陽前川
Original assignee: 株式会社東芝
Priority date: 2014-03-05
Filing date: 2014-09-10
Publication date: 2015-09-11
Also published as: JP2017078570A

Abstract

In an embodiment, a breath diagnosis device is provided with a detection unit and a processing unit. The detection unit detects a first signal dependent on the amount of a first substance in a sample gas including breath that includes a first substance and a second substance different from the first substance and a second signal dependent on the amount of a second substance in the sample gas. A processing unit calculates a first concentration of the first substance in the sample gas and a second concentration of the second substance in the sample gas on the basis of the first signal and second signal detected by the detection unit. The processing unit calculates a corrected concentration in which the second concentration is corrected on the basis of the first concentration, the second concentration, and a third concentration of the first substance in the atmosphere.

Description

Breath diagnostic device

Embodiments of the present invention relate to a breath diagnostic device.

In the breath diagnostic apparatus, the gas of breath is measured. The measurement results facilitate disease prevention and early detection. In the breath diagnostic apparatus, it is desirable to obtain accurate measurement results.

JP, 2013-11620, A

Embodiments of the present invention provide an accurate breath diagnostic device.

According to an embodiment of the present invention, a breath diagnostic apparatus is provided that includes a detection unit and a processing unit. The detection unit includes: a first signal depending on an amount of the first substance in a sample gas including exhalation containing a first substance and a second substance different from the first substance; and a first signal in the sample gas Detecting a second signal dependent on the amount of the second substance. The processing unit is configured to select a first concentration of the first substance in the sample gas and a second concentration of the second substance in the sample gas based on the first signal and the second signal detected by the detection section. Calculate the concentration. The processing unit calculates a correction concentration obtained by correcting the second concentration based on the first concentration, the second concentration, and a third concentration of the first substance in the atmosphere.

1 is a schematic view illustrating a breath diagnostic apparatus according to a first embodiment; It is a flowchart figure which illustrates operation of a breath diagnostic device concerning a 1st embodiment. FIG. 3A to FIG. 3C are schematic views illustrating another breath diagnostic apparatus according to the first embodiment. FIG. 8 is a schematic view illustrating the operation of another breath diagnosis device according to the first embodiment; FIG. 5A and FIG. 5B are schematic views illustrating characteristics of the breath diagnostic apparatus according to the first embodiment. FIG. 6A and FIG. 6B are schematic cross sections illustrating a part of the breath diagnostic apparatus according to the first embodiment. FIGS. 7A to 7C are schematic views illustrating the breath diagnostic apparatus according to the second embodiment. FIG. 8A to FIG. 8C are schematic views illustrating a part of the breath diagnostic apparatus according to the embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the ratio of sizes between parts, and the like are not necessarily the same as the actual ones. In addition, even in the case of representing the same portion, the dimensions and ratios may be different from one another depending on the drawings.
In the specification of the present application and the drawings, the same elements as those described above with reference to the drawings are denoted by the same reference numerals, and the detailed description will be appropriately omitted.

First Embodiment
FIG. 1 is a schematic view illustrating the breath diagnostic apparatus according to the first embodiment.
As shown in FIG. 1, the breath diagnostic apparatus 110 according to the present embodiment includes a detection unit 40 and a processing unit 45.

The detection unit 40 detects a substance in the sample gas 50 including the exhalation 50a. The exhalation 50a is exhalation of an animal including, for example, a human. The exhalation 50 a contains the first substance 51 and the second substance 52. The first substance 51 is, for example, carbon dioxide. The second substance 52 is, for example, acetone. The second substance 52 is a substance related to the purpose of diagnosis in the breath diagnostic apparatus 110. For example, when suffering from diabetes, the concentration of acetone in the exhaled breath 50a is increased as compared to when in health. In the breath diagnostic apparatus 110, the health condition is diagnosed by measuring the concentration of a substance (for example, acetone or the like). Examples of the substance will be described later. On the other hand, the first substance 51 is a substance to be a reference when detecting the second substance 52.

The detection unit 40 detects the first signal and the second signal. The first signal depends on the amount of the first substance in the sample gas 50. The second signal depends on the amount of the second substance 52 in the sample gas 50.

For example, the sample gas 50 may include the breath 50a of the subject and the atmosphere. That is, not all of the sample gas 50 is necessarily the breath 50a. In the sample gas 50, the exhalation 50a and other gas (atmosphere) are mixed.

The processing unit 45 processes the first signal and the second signal detected by the detection unit 40. An example of the operation of the processing unit 45 will be described later.

As shown in FIG. 1, the breath diagnostic apparatus 110 further includes a supply unit 10i, a light source unit 30, and a cell unit 20. In this example, the detection unit 40 performs detection using light.

The sample gas 50 is supplied to the supply unit 10i.

The light source unit 30 emits measurement light 30L. In this example, the light source unit 30 includes a semiconductor light emitting element 30a and a drive unit 30b. The driving unit 30 b is electrically connected to the semiconductor light emitting element 30 a. The driving unit 30 b supplies power for light emission to the semiconductor light emitting element 30 a. As described later, for example, a quantum cascade laser (QCL) is used as the semiconductor light emitting element 30a. An example of the semiconductor light emitting device 30a will be described later.

The measurement light 30L includes a wavelength absorbed by the substance contained in the breath 50a. The measurement light 30L includes infrared light (infrared light). The measurement light 30L is, for example, not less than 0.7 micrometers (μm) and not more than 1000 μm. For example, the measurement light 30L may be 2.5 μm or more and 14 μm or less.

The cell unit 20 includes a first reflection unit 21 and a second reflection unit 22. The first reflecting portion 21 and the second reflecting portion 22 are reflective to the measurement light 30L.

The sample gas 50 introduced from the supply unit 10i is introduced into the space 23s between the first reflection unit 21 and the second reflection unit 22.

For example, the cell unit 20 further includes, for example, the cell 23. For example, the cell 23 forms a space 23s. At least a part of the space 23 s is disposed between the first reflecting portion 21 and the second reflecting portion 22.

The measurement light 30L passes through, for example, the space 23s in a state where the sample gas 50 is introduced into the space 23s. For example, the measurement light 30L is reflected by the first reflecting portion 21 and the second reflecting portion 22, and reciprocates between the first reflecting portion 21 and the second reflecting portion 22 (space 23s) a plurality of times. A part of the measurement light 30L is absorbed by the substances (the first substance 51 and the second substance 52) contained in the sample gas 50. The component of the wavelength specific to the substance in the measurement light 30L is absorbed. The degree of absorption depends on the concentration of the substance.

The detection unit 40 detects, for example, the measurement light 30L that has passed through the space 23s in a state where the sample gas 50 is introduced into the space 23s.

For the detection unit 40, an element having sensitivity in the infrared region is used. For example, a thermopile or a semiconductor element (for example, MCT (HgCdTe)) or the like is used for the detection unit 40. In the embodiment, the detection unit 40 is optional.

In the breath diagnostic apparatus 110, the sample gas 50 including the breath 50a is irradiated with the measurement light 30L, and the absorption of the measurement light 30L by the substance (the first substance 51 and the second substance 52) contained in the breath 50a is measured. Ru. Thereby, the concentration of the substance contained in the breath 50a is measured.

In the breath diagnostic apparatus 110, the sample gas 50 introduced from the supply unit 10i is introduced into the cell unit 20 through the first pipe 15a. The first pipe 15 a is provided between the supply unit 10 i and the cell unit 20. On the other hand, the sample gas 50 introduced into the cell unit 20 reaches the discharge unit 10 o through the second pipe 15 b. The sample gas 50 is discharged to the outside through the discharge unit 10o.

In this example, a housing 10 w is further provided. For example, the cell unit 20, the light source unit 30, the detection unit 40, the first pipe 15a and the second pipe 15b are stored in the housing 10w.

In this example, the first optical component 36 a is provided between the light source unit 30 and the cell unit 20 on the light path of the measurement light 30 </ b> L. A second optical component 36 b is provided between the cell unit 20 and the detection unit 40 on the optical path. These optical components include, for example, at least one of a condensing optical element and a collimating optical element. A filter may be used for these optical components. An optical switch may be used for these optical components. The optical components may be provided or omitted as necessary.

Thus, the breath diagnostic apparatus 110 is provided with the cell unit 20 including the space 23s into which the sample gas 50 is introduced, and the light source unit 30 that emits the measurement light 30L. The detection unit 40 detects the measurement light 30L that has passed through the space 23s into which the sample gas 50 has been introduced, and detects a second signal. In this example, the detection unit 40 detects the measurement light 30L that has passed through the space 23s into which the sample gas 50 is introduced, and detects the first signal.

In the breath diagnostic apparatus 110, the processing unit 45 processes the detection signals (first and second signals) obtained by the detection unit 40. Hereinafter, an example of the operation of the processing unit 45 will be described.

FIG. 2 is a flowchart illustrating the operation of the breath diagnostic apparatus according to the first embodiment.
As shown in FIG. 2, based on the first signal and the second signal detected by the detection unit 40, the first concentration of the first substance 51 in the sample gas 50 and the second substance 52 in the sample gas 50. And the second concentration of the light source (step S110). For example, the ratio of the intensity of the measurement light 30L emitted from the sample gas 50 to the intensity of the measurement light 30L incident on the sample gas 50 is calculated. The wavelengths absorbed by the first substance 51 and the second substance 52 are different. The first concentration and the second concentration are calculated by finding the above ratio at a specific wavelength.

Then, based on the first concentration, the second concentration, and the third concentration of the first substance 51 in the air, a corrected concentration in which the second concentration is corrected is calculated (step S120).

That is, as described above, the sample gas 50 may contain other gas (for example, the atmosphere) in addition to the breath 50a. If another gas is contained, the concentration of the substance in the sample gas 50 is different from the concentration of the substance in the breath 50a. Therefore, when correction is not performed, the concentration of the breath 50a is not accurate because it is different from the original concentration.

For example, when the subject blows breath into the supply unit 10i of the breath diagnostic apparatus 110, the atmosphere may flow together. When replacing the gas inside the cell unit 20 with the exhalation 50a, all the gas may not be replaced by the exhalation 50a due to turbulent flow or the like. Furthermore, when the subject's breathing is shallow, gas exchange in the lung may be insufficient and air may be directly blown into the supply unit 10i. In these cases, the concentration of the target substance becomes inaccurate. Stable measurement results can not be obtained.

On the other hand, in the breath diagnostic apparatus 110 according to the present embodiment, the concentration of the target substance (the second substance 52) is corrected by the concentration of the reference substance (the first substance 51). The corrected corrected density is used for diagnosis.

That is, in the calculation of the correction concentration, the proportion of the exhalation 50 a contained in the sample gas 50 is estimated. The second density is corrected according to the ratio to calculate a corrected density.

For example, the proportion of exhalation 50a contained in the sample gas 50 is estimated. The second density is corrected according to the ratio to calculate a corrected density.

At this time, the concentration of the first substance 51 (the substance to be referred to) is determined in advance. For example, when the first substance 51 is carbon dioxide, the concentration of carbon dioxide contained in the exhaled breath 50a breathed out sufficiently deeply by a standard human being is, for example, about 40,000 ppm. This concentration may depend on various conditions including, for example, the sex, age, height and weight of the subject. This concentration may be determined for each subject if necessary. The concentration may be determined individually for each of gender, age, height and weight.

For example, the concentration of carbon dioxide in exhaled breath is higher than the concentration of carbon dioxide in the atmosphere. This is because carbon dioxide is increased by respiration. Therefore, the concentration of breath 50a (or the concentration of the atmosphere) in the sample gas 50 can be estimated by using, for example, a substance that changes due to respiration as a reference substance, such as carbon dioxide.

For example, the concentration of the first substance 51 in the sample gas 50 is set to a first concentration C1. The concentration of the second substance 52 in the sample gas 50 is set to a second concentration C2. The first concentration C1 and the second concentration C2 are measured values. The concentration of the first substance 51 in the atmosphere is taken as a third concentration C3. The third concentration C3 is predetermined for the first substance 51. When the first substance 51 is carbon dioxide, the third concentration C3 is about 400 ppm. If the third concentration changes due to the temperature, humidity, atmospheric pressure, etc. of the atmosphere, the third concentration C3 may be changed as necessary.

On the other hand, the concentration determined for the first substance 51 is taken as a fourth concentration C4. The fourth concentration C4 is predetermined for the first substance 51. When the first substance 51 is carbon dioxide, the fourth concentration C4 is about 40,000 ppm.

For example, the proportion of the exhalation 50a in the sample gas 50 is X. The proportion of the atmosphere in the sample gas 50 is (1-X).

At this time, the first concentration C1, the third concentration C3 and the fourth concentration C4 satisfy the following relationship.

C1 = X · C4 + (1-X) C3
Therefore,
X = (C1-C3) / (C4-C3)
It becomes.

On the other hand, let the original value of the concentration of the target second substance 52 be the fifth concentration C5. The fifth density C5 is the corrected density after correction. The fifth concentration C5 corresponds to the concentration of the second substance 52 when all of the sample gas 50 is the breath 50a.

The second concentration C2 (the concentration of the measurement result) and the fifth concentration C5 satisfy the following relationship.

C2 = X · C5
Therefore, the fifth concentration C5 is expressed as follows.

C5 = C2 · (C4-C3) / (C1-C3)
In the present embodiment, the measured second density C2 is corrected, and the fifth density C5 (corrected density) is used as a value after correction.

Thereby, even when the sample gas 50 contains other gases such as the atmosphere in addition to the breath 50a, accurate results can be stably obtained.

As described above, in the embodiment, the correction density (fifth density) is a value corresponding to C2 · (C4−C3) / (C1−C3). This value itself may be used. It may include an error. For example, the correction density may be 0.9 times or more and 1.1 times or less of C2 · (C4−C3) / (C1−C3). The correction concentration corresponds to the concentration (original concentration) of the second substance 52 in the breath 50a. In the embodiment, as the first substance 51, a substance having a different concentration in the atmosphere and the concentration in the breath 50a is selected. For example, carbon dioxide changes concentration by respiration. Oxygen also changes concentration by breathing. Such a substance is used as the first substance 51. That is, the concentration of the first substance 51 in the atmosphere (third concentration C3) is different from the concentration of the first substance 51 in the breath 50a.

In the embodiment, for example, the first substance 51 contains at least one of carbon dioxide and oxygen.

On the other hand, the second substance 52 is a substance targeted for diagnosis.
The second substance 52 is, for example, a carbon dioxide isotope. In this case, for example, information on H. pylori can be obtained. The second substance 52 is, for example, methane. In this case, for example, information on intestinal anaerobic bacteria can be obtained. The second substance 52 is, for example, ethanol. In this case, for example, information on drinking can be obtained. The second substance 52 is, for example, acetaldehyde. In this case, for example, information on drinking metabolites and lung cancer can be obtained. The second substance 52 is, for example, acetone. In this case, for example, information on diabetes can be obtained. The second substance 52 is, for example, nitric oxide. In this case, for example, information on asthma can be obtained. The second substance 52 is, for example, ammonia. In this case, for example, information on hepatitis can be obtained. The second substance 52 is, for example, nonanal. In this case, for example, information on lung cancer can be obtained.

In the embodiment, the second substance 52 contains at least one of carbon dioxide, methane, ethanol, acetaldehyde, acetone, carbon monoxide, ammonia and nonanal. In embodiments, the second material 52 is optional.

FIG. 3A to FIG. 3C are schematic views illustrating another breath diagnostic apparatus according to the first embodiment.
In these figures, the reflection part and the like are omitted.

As shown in FIG. 3A, in the breath diagnostic apparatus 111 according to the present embodiment, the light source unit 30 is provided with a first light emitting unit 38a and a second light emitting unit 38b. The first light emitting unit 38a emits the first light L1 of the first wavelength. The second light emitting unit 38b emits the second light L2 of the second wavelength. The second wavelength is different from the first wavelength. The first light emitting unit 38a and the second light emitting unit 38b are driven by, for example, the driving unit 30b.

For example, when carbon dioxide is used as the first substance 51, the first wavelength is, for example, about 9 μm. The first wavelength may be, for example, about 5 μm. When using acetone as the second substance 52, the second wavelength is, for example, about 7 μm. The second wavelength may be, for example, about 8 μm. These wavelengths are chosen according to the substance.

Semiconductor light emitting elements (for example, quantum cascade lasers or the like) are used as the first light emitting unit 38 a and the second light emitting unit 38 b. These light emitting units are included in the semiconductor light emitting element 30a.

The measurement light 30L includes a first light L1 of a first wavelength and a second light L2 of a second wavelength. For example, the detection unit 40 detects a first signal by the first light L1, and detects a second signal by the second light L2.

In this example, an optical element unit (first optical element unit 37a) is provided. The first optical element unit 37a is provided between the light source unit 30 and the detection unit 40 on the optical path of the measurement light 30L. In this example, the first optical element unit 37a is provided between the light source unit 30 and the space 23s on the optical path. The first optical component 36a is disposed between the first optical element portion 37a and the space 23s. The first optical element portion 37a reflects one of the first light L1 and the second light L2 and transmits the other of the first light L1 and the second light L2. The first optical element unit 37a is, for example, a beam splitter.

By using the first optical element unit 37a, for example, the first light L1 and the second light L2 can pass through the same place in the space 23s. If the concentration of the exhalation 50a is uneven in the space 23s, accurate measurement is possible.

In this example, a part of the first light L1 is coaxial with a part of the second light L2. At least a portion of the light path of the first light L1 overlaps with at least a portion of the light path of the second light L2. This can improve the accuracy.

The transmittance of the first light L1 in the passage of the space 23s into which the sample gas 50 is introduced is, for example, 0.1% or more and 99.9% or less. The transmittance of the second light L2 in the passage of the space 23s into which the sample gas 50 is introduced is, for example, 0.1% or more and 99.9% or less.

For example, when the amount of absorption by the first substance 51 in the first light L1 is excessively large, the amount of transmitted light becomes excessively small. In that case, it becomes difficult for the detection unit 40 to measure light. Therefore, the transmittance is preferably 0.1% or more. When the amount of absorption by the first substance 51 in the first light L1 is excessively small, the difference between the amount of incident light and the amount of transmitted light becomes excessively small. In that case, it becomes difficult for the detection unit 40 to measure the change in the amount of transmitted light. Therefore, the transmittance is preferably 99.9% or less.

As shown in FIG. 3B, in the breath diagnostic apparatus 112 according to the present embodiment, the detection unit 40 includes a first detection element 40a and a second detection element 40b. The first detection element 40a detects the first light L1. The second detection element 40b detects the second light L2.

In this example, a second optical element unit 37 b is provided. The second optical element unit 37 b is provided between the space 23 s and the detection unit 40 on the optical path of the measurement light 30 L. The second optical element unit 37 b is, for example, a beam splitter.

As shown in FIG. 3C, in the breath diagnostic apparatus 113 according to the present embodiment, a signal processing unit 41 is provided. The signal processing unit 41 is connected to the first detection element 40a. The signal processed by the signal processing unit 41 is supplied to the processing unit 45.

For example, the first light emitting unit 38a emits the first light L1 at the first frequency. The second light emitting unit 38b emits the second light L2 at the second frequency. The second frequency is different from the first frequency. Such an operation is controlled by the drive unit 30b. The signal obtained by the first detection element 40 a is processed by the signal processing unit 41 corresponding to these frequencies. For example, the signal processing unit 41 extracts a signal of the first frequency. For example, the signal processing unit 41 extracts a signal of the second frequency. The signal processing unit 41 performs, for example, frequency detection processing. Thereby, light of a plurality of wavelengths can be efficiently detected by one detection element.

FIG. 4 is a schematic view illustrating the operation of another breath diagnostic apparatus according to the first embodiment.
FIG. 4 illustrates the intensity DP1 of the first light L1 and the intensity DP2 of the second light L1. The horizontal axis is time.

As shown in FIG. 4, the first light L1 and the second light L2 are emitted at frequencies different from each other. By extracting the detection signal according to the frequency, each of the intensity of the first light L1 and the intensity of the second light L2 can be separated. For example, the detection unit 40 detects the first light L1 in a first cycle and detects the second light L2 in a second cycle. For example, the detection unit 40 detects the first light L1 in the first period P1. The detection unit 40 detects the second light L2 in the second period P2.

FIG. 5A and FIG. 5B are schematic views illustrating characteristics of the breath diagnostic apparatus according to the first embodiment.
These figures illustrate the wavelength characteristics of the measurement light 30L. The horizontal axis is the wavelength λm. The vertical axis is the intensity of the measurement light 30L.

As shown in FIG. 5A, the measurement light 30L includes a component of the first wavelength λ1 and a component of the second wavelength λ2. In this example, it further includes the components between them. That is, the measurement light 30L further includes the third light of the third wavelength λ3 between the first wavelength λ1 and the second wavelength λ2. For example, a broad QCL is used as the light source unit 30. The broad QCL emits light having a wavelength in the range of the first wavelength λ1 to the second wavelength λ2. For example, the light intensity (absorptivity) is sequentially measured for the light of the first wavelength λ1, the third wavelength λ3, and the second wavelength λ2. The concentration is calculated based on this result. The wavelength for measuring the concentration may be changed continuously or may be changed discretely. For example, the measurement light 30L has a first wavelength λ1, a second wavelength λ2, and a wavelength between the first wavelength λ1 and the second wavelength λ2. The detection unit 40 may detect the measurement light 30L by changing the wavelength between the first wavelength λ1 and the second wavelength λ2.

As shown in FIG. 5B, the measurement light 30L may have a first peak of the first wavelength λ1 and a second peak of the second wavelength λ2.

FIG. 6A and FIG. 6B are schematic cross sections illustrating a part of the breath diagnostic apparatus according to the first embodiment.
In the example shown in FIG. 6A, the first light emitting unit 38a and the second light emitting unit 38b are provided on the substrate 35. The first light emitting unit 38a includes a first ridge portion RG1. The second light emitting unit 38 b includes a second ridge portion RG2. Measurement light 30L (laser light) of different wavelength is emitted from each light emitting portion.

That is, in this example, the light source unit 30 includes a semiconductor laser element (semiconductor light emitting element 30a). The semiconductor laser device includes a first ridge portion RG1 that emits the first light L1 and a second ridge portion RG2 that emits the second light L2.

In the example shown in FIG. 6B, the first light emitting unit 38a is provided on the substrate 35, and the second light emitting unit 38b is provided on the first light emitting unit 38a. Thus, a plurality of light emitting units may be stacked.

Second Embodiment
FIGS. 7A to 7C are schematic views illustrating the breath diagnostic apparatus according to the second embodiment.
As shown in FIG. 7A, the detection unit 40 and the processing unit 45 are also provided in the breath diagnostic apparatus 120 according to the present embodiment. Also in the breath diagnostic apparatus 120, a light source unit 30 and a cell unit 20 are further provided. A supply unit 10i, a discharge unit 10o, and a housing 10w (not shown) may be further provided.

In the breath diagnostic apparatus 120, detection of the second substance 52 is performed by the measurement light 30L. Then, the detection of the first substance 51 is performed without using the measurement light 30L.

That is, in the breath diagnostic apparatus 120, the detection unit 40 is provided with a first detector 43a in addition to the first detection element 40a (light detection element). The first detector 43 a detects the first substance 51 in the sample gas 50. For example, when the first substance 51 is carbon dioxide, a semiconductor sensor can be used as the first detector 43a. The concentration of carbon dioxide can be measured by the semiconductor sensor. The concentration of oxygen can also be measured by the zirconia sensor.

In this example, the first detector 43a is disposed in the space 23s. In this example, the first detector 43a detects the first substance 51 in the space 23s into which the sample gas 50 has been introduced. The first detector 43a is disposed close to the light path of the measurement light 30L. This enables accurate detection even when the concentration of the first substance 51 is uneven in the space 23s.

As shown in FIG. 7B, in the breath diagnostic apparatus 121 according to the present embodiment, the detection unit 40 is provided with a plurality of detectors. In this example, a second detector 43 b and a third detector 43 c are provided. The second detector 43 b and the second detector 43 c detect the concentration of the first substance 51 in the sample gas 50. In this example, these detectors detect the first substance 51 in the space 23s into which the sample gas 50 is introduced. For these detectors, for example, semiconductor sensors can be used.

In this example, the second detector 43b is aligned with the first detector 43a along the optical path of the measurement light 30L in the space 23s. By arranging a plurality of detectors along the light path, more accurate values can be obtained.

As shown in FIG. 7C, in the breath diagnostic apparatus 122 according to the present embodiment, one end of a third pipe 15c is connected to the first pipe 15a. A first detector 43a is provided at the other end of the third pipe 15c. A part of the supplied sample gas 50 is supplied to the space 23s. Another part of the sample gas 50 flows toward the first detector 43a via the third pipe 15c. Thus, the first detector 43a may detect the concentration of the first substance 51 at a position different from the space 23s.

Hereinafter, an example of the light source unit 30 will be described.
FIG. 8A to FIG. 8C are schematic views illustrating a part of the breath diagnostic apparatus according to the embodiment.
FIG. 8A is a schematic perspective view. FIG. 8 (b) is a cross-sectional view taken along line A1-A2 of FIG. 8 (a). FIG. 8C is a schematic view illustrating the operation of the light source unit 30.
In this example, a semiconductor light emitting element 30 a is used as the light source unit 30. A laser is used as the semiconductor light emitting element 30a. In this example, a quantum cascade laser is used.

As shown in FIG. 8A, the semiconductor light emitting device 30a includes the substrate 35, the laminate 31, the first electrode 34a, the second electrode 34b, and the dielectric layer 32 (first dielectric layer). , And the insulating layer 33 (second dielectric layer).

A substrate 35 is provided between the first electrode 34 a and the second electrode 34 b. The substrate 35 includes a first portion 35a, a second portion 35b, and a third portion 35c. These parts are arranged in one plane. This plane intersects (eg, is parallel to) the direction from the first electrode 34a to the second electrode 34b. The third portion 35c is disposed between the first portion 35a and the second portion 35b.

The stacked body 31 is provided between the third portion 35c and the first electrode 34a. A dielectric layer 32 is provided between the first portion 35a and the first electrode 34a and between the second portion 35b and the first electrode 34a. An insulating layer 33 is provided between the dielectric layer 32 and the first electrode 34a.

The stacked body 31 has a stripe shape. The stacked body 31 functions as a ridge waveguide RG. The two end faces of the ridge waveguide RG become mirror surfaces. The light 31L emitted from the laminate 31 is emitted from the end face (light emitting surface). The light 31L is an infrared laser light. The optical axis 31Lx of the light 31L is along the extending direction of the ridge waveguide RG.

As shown in FIG. 8B, the stacked body 31 includes, for example, a first cladding layer 31a, a first guide layer 31b, an active layer 31c, a second guide layer 31d, and a second cladding layer 31e. ,including. These layers are arranged in this order along the direction from the substrate 35 toward the first electrode 34a. Each of the refractive index of the first cladding layer 31a and the refractive index of the second cladding layer 31e is determined by the refractive index of the first guide layer 31b, the refractive index of the active layer 31c, and the refractive index of the second guide layer 31d. Too low. The light 31 L generated in the active layer 31 c is confined in the stack 31. The first guide layer 31 b and the first cladding layer 31 a may be collectively referred to as a cladding layer. The second guide layer 31d and the second cladding layer 31e may be collectively referred to as a cladding layer.

The stacked body 31 has a first side 31 sa and a second side 31 sb perpendicular to the optical axis 31 Lx. The distance 31w (width) between the first side surface 31sa and the second side surface 31sb is, for example, 5 μm or more and 20 μm or less. Thereby, for example, control of the horizontal lateral mode is facilitated, and output improvement is facilitated. If the distance 31 w is excessively long, high-order modes are likely to occur in the horizontal transverse mode, and it is difficult to increase the output.

The refractive index of the dielectric layer 32 is lower than the refractive index of the active layer 31c. Thus, the ridge waveguide RG is formed by the dielectric layer 32 along the optical axis 31Lx.

As shown in FIG. 8C, the active layer 31c has, for example, a cascade structure. In the cascade structure, for example, the first region r1 and the second region r2 are alternately stacked. The unit structure r3 includes a first region r1 and a second region r2. A plurality of unit structures r3 are provided.

For example, the first barrier layer BL1 and the first quantum well layer WL1 are provided in the first region r1. The second barrier layer BL2 is provided in the second region. For example, the third barrier layer BL3 and the second quantum well layer WL2 are provided in another first region r1a. A fourth barrier layer BL4 is provided in another second region r2a.

In the first region r1, an intersubband optical transition of the first quantum well layer WL1 occurs. Thereby, for example, light 31La having a wavelength of 3 μm to 18 μm is emitted.

In the second region r2, the energy of carriers c1 (for example, electrons) injected from the first region r1 can be relaxed.

In the quantum well layer (for example, the first quantum well layer WL1), the well width WLt is, for example, 5 nm or less. When the well width WLt is thus narrow, the energy levels are discretely generated, for example, the first sub-band WLa (high level Lu) and the second sub-band WLb (low level Ll). The carriers c1 injected from the first barrier layer BL1 are effectively confined in the first quantum well layer WL1.

When the carrier c1 transitions from the high level Lu to the low level Ll, the light 31La corresponding to the energy difference (the difference between the high level Lu and the low level Ll) is emitted. That is, an optical transition occurs.

Similarly, light 31 Lb is emitted in the second quantum well layer WL2 of another first region r1a. In embodiments, the quantum well layer may include a plurality of wells with overlapping wave functions. The respective high levels Lu of the plurality of quantum well layers may be identical to each other. The low levels Ll of the plurality of quantum well layers may be the same as one another.

For example, intersubband optical transitions occur in either the conduction band or the valence band. For example, recombination of holes and electrons by a pn junction is not necessary. For example, carriers c1 of either holes or electrons cause optical transition to emit light.

In the active layer 31c, for example, carriers c1 (for example, electrons) are quantized via a barrier layer (for example, the first barrier layer BL1) by a voltage applied between the first electrode 34a and the second electrode 34b. The well layer (for example, the first quantum well layer WL1) is implanted. This causes an intersubband optical transition.

The second region r2 has, for example, a plurality of subbands. The sub band is, for example, a mini band. The energy difference in the subbands is small. In the sub-bands, it is preferable to be close to the continuous energy band. As a result, the energy of the carrier c1 (electron) is relaxed.

In the second region r2, for example, light (for example, infrared light having a wavelength of 3 μm to 18 μm) is not substantially emitted. The carriers c1 (electrons) of the low level L1 of the first region r1 pass through the second barrier layer BL2, are injected into the second region r2, and are relaxed. The carrier c1 is injected into another cascaded first region r1a. An optical transition occurs in this first region r1a.

In the cascade structure, optical transition occurs in each of the plurality of unit structures r3. This makes it easy to obtain high light output in the entire active layer 31c.

Thus, the light source unit 30 includes the semiconductor light emitting element 30a. The semiconductor light emitting element 30a emits the measurement light 30L by energy relaxation of electrons in the sub-bands of the plurality of quantum wells (for example, the first quantum well layer WL1 and the second quantum well layer WL2).

For example, GaAs is used for the quantum well layers (for example, the first quantum well layer WL1 and the second quantum well layer WL2). For example, Al _x Ga _{1 -x} As (0 <x <1), for example, is used for the barrier layers (eg, the first to fourth barrier layers BL1 to BL4). At this time, for example, when GaAs is used as the substrate 35, good lattice matching can be obtained in the quantum well layer and the barrier layer.

The first cladding layer 31a and the second cladding layer 31e contain, for example, Si as an n-type impurity. The impurity concentration in these layers is, for example, 1 × 10 ¹⁸ cm ⁻³ or more and 1 × 10 ²⁰ cm ⁻³ or less (for example, about 6 × 10 ¹⁸ cm ⁻³ ). The thickness of each of these layers is, for example, 0.5 μm or more and 2 μm or less (for example, about 1 μm).

The first guide layer 31 b and the second guide layer 31 d contain, for example, Si as an n-type impurity. The impurity concentration in these layers is, for example, 1 × 10 ¹⁶ cm ⁻³ or more and 1 × 10 ¹⁷ cm ⁻³ or less (for example, about 4 × 10 ¹⁶ cm ⁻³ ). The thickness of each of these layers is, for example, 2 μm or more and 5 μm or less (for example, 3.5 μm).

The distance 31 w (the width of the stack 31, that is, the width of the active layer 31 c) is, for example, 5 μm or more and 20 μm or less (for example, about 14 μm).

The length of the ridge waveguide RG is, for example, 1 mm or more and 5 mm or less (for example, about 3 mm). The semiconductor light emitting device 30a (quantum cascade laser) operates at an operating voltage of, for example, 10 V or less. The consumption current is lower than that of a carbon dioxide gas laser device or the like. This enables low power consumption operation.

According to the embodiment, an accurate breath diagnosis device can be provided.

The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. For example, with regard to the specific configuration of each element such as the supply unit, the cell unit, the reflection unit, the light source unit, the detection unit, and the processing unit included in the breath diagnostic apparatus, the person skilled in the art can As long as the invention can be practiced similarly and similar effects can be obtained, it is included in the scope of the present invention.

Moreover, what combined any two or more elements of each specific example in the technically possible range is also included in the scope of the present invention as long as the gist of the present invention is included.

In addition, all breath diagnosis apparatuses that can be appropriately designed and implemented by those skilled in the art based on the breath diagnosis apparatus described above as the embodiment of the present invention also fall within the scope of the present invention as long as the scope of the present invention is included. Belongs to

Besides, within the scope of the concept of the present invention, those skilled in the art can conceive of various changes and modifications, and it is understood that the changes and modifications are also within the scope of the present invention. .

While certain embodiments of the present invention have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and the gist of the invention, and are included in the invention described in the claims and the equivalent scope thereof.

Claims

A first signal dependent on the amount of said first substance in a sample gas comprising exhaled breath comprising a first substance and a second substance different from said first substance, and a second signal of said second substance in said sample gas A detection unit for detecting a second signal dependent on the quantity;
The first concentration of the first substance in the sample gas and the second concentration of the second substance in the sample gas are calculated based on the first signal and the second signal detected by the detection unit. And
A processing unit that calculates a correction concentration in which the second concentration is corrected, based on the first concentration, the second concentration, and a third concentration of the first substance in the atmosphere;
Breath diagnostic equipment with.
The breath diagnostic apparatus according to claim 1, wherein the calculation includes estimating the proportion of the exhalation contained in the sample gas and calculating the correction concentration according to the proportion.
The breath diagnostic apparatus according to claim 1, wherein the calculation calculates the correction concentration further based on a fourth concentration determined for the first substance.
The first concentration is C1.
The second concentration is C2.
The third concentration is C3
When the fourth concentration is C4,
4. The breath diagnostic apparatus according to claim 3, wherein the correction concentration is a value corresponding to C2 · (C4−C3) / (C1−C3).
5. The breath diagnostic apparatus according to claim 4, wherein the correction concentration is 0.9 times or more and 1.1 times or less of C2 · (C4−C3) / (C1−C3).
The breath diagnostic apparatus according to claim 1, wherein the first substance contains at least one of carbon dioxide and oxygen.
The breath diagnostic apparatus according to claim 6, wherein the second substance contains at least one of carbon dioxide, methane, ethanol, acetaldehyde, acetone, carbon monoxide, ammonia and nonanal.
A cell unit including a space into which the sample gas is introduced;
A light source unit that emits measurement light;
And further
The measurement light includes a first light of a first wavelength and a second light of a second wavelength different from the first wavelength,
The breath diagnostic apparatus according to claim 1, wherein the detection unit includes a first detection element that detects the first light and a second detection element that detects the second light.
The breath diagnostic apparatus according to claim 8, wherein the detection unit detects the first signal by detecting the measurement light that has passed through the space into which the sample gas is introduced.
The breath diagnostic apparatus according to claim 8, wherein the measurement light further includes third light of a third wavelength between the first wavelength and the second wavelength.
The breath diagnostic apparatus according to claim 10, wherein at least a part of the light path of the first light overlaps with at least a part of the light path of the second light.
It further comprises an optical element unit provided between the light source unit and the detection unit on the optical path of the measurement light,
The breath diagnostic apparatus according to claim 11, wherein the optical element unit reflects one of the first light and the second light and transmits the other of the first light and the second light.
The detection unit is
Detecting the first light during a first period,
The breath diagnostic apparatus according to claim 10, wherein the second light is detected in a second period.
The light source unit includes a semiconductor laser device,
11. The breath diagnostic apparatus according to claim 10, wherein the semiconductor laser device includes a first ridge portion that emits the first light and a second ridge portion that emits the second light.
9. The breath diagnostic apparatus according to claim 8, wherein the detection unit includes a first detector that detects the first substance in the sample gas.
The detection unit further includes a second detector that detects the first substance in the sample gas,
The breath diagnostic apparatus according to claim 15, wherein the second detector is aligned with the first detector along an optical path of the measurement light in the space.
A cell unit including a space into which the sample gas is introduced;
A light source unit that emits measurement light;
And further
The measurement light has a first wavelength, a second wavelength different from the first wavelength, and a wavelength between the first wavelength and the second wavelength,
The breath diagnostic apparatus according to claim 1, wherein the detection unit detects the measurement light by changing a wavelength between the first wavelength and the second wavelength.
The cell unit is
A first reflecting portion that is reflective to the measurement light;
A second reflecting portion that is reflective to the measurement light;
Including
The space is disposed between the first reflective portion and the second reflective portion,
9. The breath diagnostic apparatus according to claim 8, wherein the measurement light reflects the first reflection part and the second reflection part and passes through the space.
The light source unit includes a semiconductor light emitting element,
The breath diagnostic apparatus according to claim 8, wherein the semiconductor light emitting element emits the measurement light by energy relaxation of electrons in a plurality of sub-bands of quantum wells.
The transmittance of the first light in the passage of the space into which the sample gas is introduced is 0.1% to 99.9%,
The breath diagnostic apparatus according to claim 8, wherein the transmittance of the second light in the passage of the space into which the sample gas is introduced is 0.1% to 99.9%.