Biological information detection device and biological information detection method

Abstract

The present invention provides a biological information detection device including a first laser oscillator that oscillates a first pulsed laser beam having an appropriate wavelength for detecting lactic acid or lactate, a second laser oscillator that oscillates a second pulsed laser beam having an appropriate wavelength for detecting pyruvic acid, an irradiation mechanism that irradiates blood with the first pulsed laser beam and the second pulsed laser beam, a light-receiving sensor that receives the detection laser beam output from the blood, and a control unit that controls the operation of each component. The control unit outputs oscillation commands to the first laser oscillator and the second laser oscillator to oscillate the first pulsed laser beam and the second pulsed laser beam, respectively, at a constant cycle, and extracts detection signals from the light-receiving sensor as section data at times corresponding to the constant cycle, and calculates the amounts of lactic acid or lactate and pyruvic acid in the blood based on the section data.

Description

[Technical Field]

[0001] The present invention relates to a biological information detection device and a biological information detection method, and more particularly to a biological information detection device and a biological information detection method for acquiring the amounts of lactic acid and lactate present in blood. [Background technology]

[0002] Lactic acid is produced in large amounts in human blood when blood sugar is metabolized in an anaerobic environment, such as during strenuous exercise. The concentration of lactic acid in blood is used as a measure of the degree of blood circulation, and is used as an indicator of shock or circulatory failure, for example.

[0003] As an example, in the case of sepsis, a condition in which bacteria or other pathogens enter the blood and damage organs throughout the body, monitoring the lactate concentration in the blood can be used to determine whether the patient's condition will worsen during postoperative care of a patient who has undergone surgery or when transporting an emergency patient showing symptoms of shock. Such measurement of blood lactate concentration is generally performed by analyzing blood drawn from the patient, but simple and continuous measurement is difficult, and risk management of infections associated with blood drawing is essential.

[0004] As one way to improve this, for example, Patent Document 1 discloses a measurement method in which near-infrared light is irradiated from a probe onto a measurement site in a living body, the light that is transmitted through the living body and scattered is received by a light-receiving unit, a wavelength in the near-infrared region that is absorbed by lactic acid is set as the measurement wavelength, the light intensity at that measurement wavelength is detected, and the lactate concentration in the living body is quantitatively analyzed based on the light intensity. This method is said to require no reagents, to be non-invasive, and to be able to measure differences in lactate concentration depending on the measurement site.

[0005] Patent Document 2 discloses a method for real-time monitoring of a subject's blood constituent level, the method including the steps of providing a system-on-chip with a tunable hybrid III-V / IV laser sensor, instructing the system-on-chip to monitor the subject's blood constituent level by sending a swept laser signal to an optical fiber interface, guiding the signal to the subject's blood via the optical fiber interface, collecting a reflected signal from the blood via the optical fiber interface after the signal interacts with the blood, and guiding the reflected signal to a reflected light photodiode. The reflected signal is an optical signal, converting the optical signal into an electrical signal, and processing the electrical signal with a microcontroller to convert it into a calibrated blood constituent level. This allows multiple data points to be collected continuously over a certain period of time, providing important information on historical trends that may be important in evaluating the effectiveness of treatment. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 9-126995 [Patent Document 2] Special Publication No. 2020-520768 Summary of the Invention [Problem to be solved by the invention]

[0007] Although the above-mentioned conventional technologies can non-invasively measure the concentration of lactate in a living body, particularly in blood, the irradiated light is emitted from a light source having a predetermined wavelength range (e.g., a halogen lamp or a semiconductor laser), and therefore, in order to selectively and accurately detect lactate in particular, calibration is required to select a wavelength or wavelength band suitable for measuring lactate from the optical signal received by the light-receiving unit. If this calibration is not performed appropriately, the accuracy of the measurement results will be significantly reduced.

[0008] In addition to lactic acid, blood also contains pyruvic acid, which has a chemical structure and absorbance characteristics similar to those of lactic acid. As described above, since lactic acid and pyruvic acid have similar chemical structures and absorbance characteristics, there is a high probability that the optical signal detected in the wavelength range for measuring lactic acid, as in the conventional technology, will contain not only lactic acid but also pyruvic acid.

[0009] In light of the above, an object of the present application is to provide a biological information detection device and a biological information detection method that can acquire the concentrations of lactic acid and pyruvic acid contained in blood independently of each other. [Means for solving the problem]

[0010] A biological information detection device according to one aspect of the present invention includes a first laser oscillator that oscillates a first pulse laser beam having an appropriate wavelength for detecting lactic acid or lactate; a second laser oscillator that oscillates a second pulse laser beam having an appropriate wavelength for detecting pyruvic acid; an irradiation mechanism that irradiates the first pulse laser beam and the second pulse laser beam onto blood containing lactic acid or lactate and pyruvic acid; a light-receiving sensor that receives the detection laser beam output from the blood; and a control unit that controls the operation of each component, wherein the control unit outputs oscillation commands to the first laser oscillator and the second laser oscillator to oscillate the first pulse laser beam and the second pulse laser beam, respectively, at a constant cycle, and extracts detection signals from the light-receiving sensor as section data at a time corresponding to the constant cycle, and calculates the amounts of lactic acid or lactate and pyruvic acid in the blood based on the section data.

[0011] Furthermore, according to another aspect of the present invention, a biological information detection method includes irradiating blood containing lactic acid or lactate and pyruvic acid with a first pulse laser beam having an appropriate wavelength for detecting lactic acid or lactate and a second pulse laser beam having an appropriate wavelength for detecting pyruvic acid, receiving detection laser beams output from the blood with a light-receiving sensor, and acquiring the amounts of lactic acid or lactate and pyruvic acid in the blood, the method comprising: oscillating the first pulse laser beam and the second pulse laser beam at a constant period; extracting detection signals from the light-receiving sensor as section data for a time period corresponding to the constant period for each appropriate wavelength of the first pulse laser beam and the second pulse laser beam; and calculating the amounts of lactic acid or lactate and pyruvic acid in the blood based on the section data. [Effects of the Invention]

[0012] According to one aspect of the present invention, the concentrations of lactic acid and pyruvic acid contained in the blood can be obtained independently, thereby enabling more accurate determination of the amounts of lactic acid and lactate contained in the blood. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a schematic diagram showing a configuration of a biological information detection device according to a first embodiment, which is a typical example of the present invention. [Figure 2] 2 is a block diagram showing an example of the configuration of a laser oscillator included in the biological information detecting device shown in FIG. 1. FIG. [Figure 3] 2 is a partial cross-sectional view showing an example of the configuration of an irradiation mechanism included in the biological information detecting device shown in FIG. 1. [Figure 4] 2 is a block diagram showing an example of the configuration of a control unit included in the biological information detecting device shown in FIG. 1. FIG. [Figure 5] 1 is a flowchart showing an outline of a biological information detection method according to a first embodiment. [Figure 6A] 3 is a plan view showing an outline of an operational procedure for irradiating blood with pulsed laser light in the biological information detecting device according to the first embodiment. FIG. [Figure 6B] 3 is a partial front view illustrating an outline of an operational procedure for irradiating blood with pulsed laser light in the biological information detecting device according to the first embodiment. FIG. [Figure 6C] 3 is a partial front view illustrating an outline of an operational procedure for irradiating blood with pulsed laser light in the biological information detecting device according to the first embodiment. FIG. [Figure 7] 4 is a time series graph showing the relationship between various command signals and measurement data. [Figure 8A] 10 is a plan view showing an outline of an operational procedure for irradiating blood with pulsed laser light in a biological information detecting device according to a second embodiment. FIG. [Figure 8B] 10 is a partial front view showing an outline of an operational procedure for irradiating blood with pulsed laser light in a biological information detecting device according to a second embodiment. FIG. [Figure 8C] 10 is a partial front view showing an outline of an operational procedure for irradiating blood with pulsed laser light in a biological information detecting device according to a second embodiment. FIG. [Figure 9] 10 is a flowchart showing an outline of a biological information detection method according to a second embodiment. [Figure 10A]FIG. 10 is a plan view showing an outline of an operational procedure for irradiating blood with pulsed laser light in a biological information detecting device according to a third embodiment. [Figure 10B] FIG. 11 is a partial front view illustrating an outline of an operational procedure for irradiating blood with pulsed laser light in a biological information detecting device according to a third embodiment. [Figure 10C] FIG. 11 is a partial front view illustrating an outline of an operational procedure for irradiating blood with pulsed laser light in a biological information detecting device according to a third embodiment. [Figure 11] 4 is a time series graph showing the relationship between various command signals and measurement data. [Figure 12] FIG. 11 is a partial cross-sectional view showing an overview of a measurement unit according to a modified example of the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0014] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A biological information detection device and a biological information detection method according to a representative embodiment of the present invention will be described below with reference to the drawings.

[0015] First Embodiment Fig. 1 is a schematic diagram showing the configuration of a biological information detection device according to a first embodiment, which is a representative example of the present invention. Fig. 2 is a block diagram showing an example of the configuration of a laser oscillator included in the biological information detection device shown in Fig. 1. Fig. 2 is a partial cross-sectional view showing an example of the configuration of an irradiation mechanism included in the biological information detection device shown in Fig. 1. Fig. 4 is a block diagram showing an example of the configuration of a control unit included in the biological information detection device shown in Fig. 1.

[0016] As shown in FIG. 1, a biological information detecting device 100 according to the first embodiment includes, for example, a first laser oscillator 110 that oscillates a first pulsed laser beam LB1 having an appropriate wavelength for detecting lactic acid or lactate; a second laser oscillator 120 that oscillates a second pulsed laser beam LB2 having an appropriate wavelength for detecting pyruvic acid; an irradiation mechanism 130 that irradiates blood BL containing lactic acid or lactate and pyruvic acid with the first pulsed laser beam LB1 and the second pulsed laser beam LB2; a transport mechanism 140 that moves the irradiation mechanism 130 to any position in the X, Y, and Z directions; a sample holding mechanism 150 that moves the position in the X, Y, and Z directions of a container 152 containing the blood BL; a light-receiving sensor 160 that receives detection laser beams output from the blood BL; and a control unit 170 that controls the operation of each component.

[0017] In the following description, lactic acid or lactate and pyruvic acid contained in blood BL will be collectively referred to as the "measurement target substance" and will be represented by the symbol "MM" (see the symbol MM in FIG. 4, which will be described later).

[0018] A light source that outputs a wavelength (e.g., a wavelength with high absorption efficiency) appropriate for detecting lactic acid or lactate among the measurement target substances MM contained in blood BL is used as the first laser oscillator 110. Here, an example of the wavelength of the pulsed laser light LB appropriate for detecting lactic acid or lactate is 1480 nm.

[0019] A light source that outputs a wavelength (e.g., a wavelength with high absorption efficiency) appropriate for detecting pyruvic acid, which is one of the measurement target substances MM contained in blood BL, is used as the second laser oscillator 120. Here, an example of the wavelength of the pulsed laser light LB appropriate for detecting pyruvic acid is 1462 nm.

[0020] As shown in FIG. 2, the first laser oscillator 110 includes, as an example, an oscillation control unit 112 that controls the oscillation of a first pulse laser beam LB1 at a constant period T based on an oscillation command signal from a control unit 170, a drive power supply 113 that supplies drive power to the plurality of laser light sources 115 a, 115 b in response to an on / off signal from the oscillation control unit 112, a support unit 114 to which the laser light sources 115 a, 115 b are attached, a focusing lens 116 that focuses the pulse laser beams LBa, LBb emitted from the plurality of laser light sources 115 a, 115 b, a wavelength adjustment unit 117 that adjusts the wavelength of the focused first pulse laser beam LB1, and a transmission path 118 (e.g., an optical fiber) that transmits the first pulse laser beam LB1 to the irradiation mechanism 130.

[0021] 2 illustrates an example in which two laser light sources LBa and LBb are used as the light source of the first pulsed laser beam LB1, but three or more laser light sources may be arranged in an array or on a predetermined circumference. Furthermore, light-emitting diodes (LEDs), semiconductor lasers (LDs), or the like may be used as the plurality of laser light sources 115a and 115b for selectively emitting wavelengths appropriate for detecting the above-mentioned lactic acid, lactate salt, or pyruvic acid.

[0022] Then, pulsed laser beams LBa, LBb emitted from the plurality of laser light sources 115a, 115b are coaxially focused to increase their output, and are transmitted through wavelength tuning section 117, whereby a first pulsed laser beam LB1 selected within a predetermined appropriate wavelength range is emitted to transmission path 118. Here, an example of wavelength tuning section 117 is a bandpass filter that selectively removes light outside a predetermined range of upper and lower limits.

[0023] Although the case where drive power is directly supplied from the drive power supply 113 to the plurality of laser light sources 115a, 115b has been shown, it is also possible to provide an amplifier circuit (not shown) in the support part 114, for example, to amplify the drive power from the drive power supply 113 and supply it to the laser light sources 115a, 115b. Furthermore, the second laser oscillator 120 may have the same configuration as the first laser oscillator 110 described above, and therefore its description will be omitted.

[0024] As shown in FIG. 3 as an example, the irradiation mechanism 130 includes connectors 131a and 131b connected to transmission paths 118 and 128 that transmit the first pulsed laser beam LB1 and the second pulsed laser beam LB2, respectively, a beam splitter 132 that guides the transmitted first pulsed laser beam LB1 and second pulsed laser beam LB2 to a coaxial optical path, mirrors 133 and 134 that reflect the first pulsed laser beam LB1 and guide it to the beam splitter 132, a mirror 135 that reflects the second pulsed laser beam LB2 and guides it to the beam splitter 132, a focusing lens 136 that focuses the coaxially guided pulsed laser beam LB (i.e., laser beam obtained by superimposing the first pulsed laser beam LB1 and the second pulsed laser beam LB2) at a predetermined focal position, and a window member 137 that transmits the pulsed laser beam LB.

[0025] The first pulsed laser beam LB1 and the second pulsed laser beam LB2 introduced into the irradiation mechanism 130 via the transmission paths 118 and 128 are shaped by the condenser lens 136 into a beam profile having a predetermined beam diameter, beam cross-sectional shape, etc., and are then irradiated through the window member 137 onto the blood BL contained in the container 152. Here, although the first embodiment illustrates a case in which the pulsed laser beam LB is shaped to have a beam spot with a circular cross-section, it is also possible to shape the beam profile into any shape, such as a polygon or a line, by appropriately selecting the condenser lens.

[0026] 3, the beam splitter 132 is exemplified as an optical element that guides the first pulsed laser beam LB1 and the second pulsed laser beam LB2 into coaxial optical paths, but other optical elements may be used as long as they guide (emit) two laser beams coaxially. Also, the window member 137 is used as a member for maintaining airtightness inside the irradiation mechanism 130, but a so-called "telecentric fθ lens" may be added to the window member 137.

[0027] As an example, the transport mechanism 140 is configured as a linear drive body that moves relatively in three mutually orthogonal axial directions of X, Y and Z, and has the irradiation mechanism 130 attached to one end thereof. Note that the transport mechanism 140 may also be configured as a six- or seven-axis industrial robot equipped with a robot arm having the irradiation mechanism 130 attached to one end thereof.

[0028] As an example, the sample holding mechanism 150 is configured as a table that can move freely in three axes directions (X, Y, and Z) as shown in the figure, with a container 152 containing blood BL containing the measurement target substance MM placed on its upper surface. In addition, a light receiving sensor 160 is disposed between the upper surface of the sample holding mechanism 150 and the lower surface of the container 152 to detect transmitted light TB from the blood BL (see FIGS. 6B, 6C, etc.).

[0029] The container 152 that contains the blood BL is made of a material that is transparent to the wavelength of the pulsed laser light LB (i.e., the irradiated pulsed laser light LB passes through). As a result, the pulsed laser light LB irradiated onto the blood BL contained in the container 152 passes through the bottom surface of the container 152 as it is in an area where the measurement target substance MM is not present, and reaches the light-receiving sensor 160, so that the irradiation of the pulsed laser light LB can be detected by the light-receiving sensor 160.

[0030] 4, the control unit 170 includes a main control unit 172 that outputs operation commands to each component of the biological information detection device 100, an amount calculation unit 174 that calculates the amounts of lactic acid or lactate and pyruvic acid in the measurement target substance MM contained in the blood BL using the detection values ​​from the light-receiving sensor 160, a display unit 176 that displays the calculated amounts of lactic acid or lactate and pyruvic acid as well as various other parameters, and an input interface 178 that allows manual input of information for correcting various parameters such as measurement conditions. The main control unit 172 of the control unit 170 is connected to the first laser oscillator 110, the second laser oscillator 120, the transport mechanism 140, and the sample holding mechanism 150 by wire or wirelessly, and controls the operation of the entire biological information detection device 100 by exchanging signals with these peripheral devices.

[0031] For example, when a start signal Ss corresponding to the start of measurement is input by the user via the input interface 178, the main control unit 172 has the function of extracting, from a predetermined measurement program, operation information such as oscillation of the first laser oscillator 110 and the second laser oscillator 120 and relative movement of the transport mechanism 140 and the sample holding mechanism 150, generating oscillation signals S1o, S2o and a relative movement signal Sm for executing these operations and outputting them to each component. The main control unit 172 also has the function of outputting a first oscillation signal S1o and a second oscillation signal S2o to a quantity calculation unit 174 (described later) in synchronization with the outputs to the first laser oscillator 110 and the second laser oscillator 120, and receiving the calculation results from the quantity calculation unit 174, sending the quantity calculation results and various current parameters of the biological information detection device 100 to the display unit 176 to display them.

[0032] As described above, the quantity calculation unit 174 has a function of receiving a calculation signal Se corresponding to the start of calculation from the main control unit 172 that has received the start signal SS, and then continuously receiving and accumulating the detection signal Sd corresponding to the detection value at time t from the light-receiving sensor 160. The quantity calculation unit 174 also has a function of receiving the first oscillation signal S1o and the second oscillation signal S2o from the main control unit 172, extracting section data D corresponding to the oscillation timing of each of the first laser oscillator 110 and the second laser oscillator 120 from the time-series data of the detection signal Sd detected by the light-receiving sensor 160, and calculating the amounts of lactic acid or lactate and pyruvic acid in the measurement target substance MM contained in the blood BL based on the section data D. The calculated amounts of lactic acid or lactate and pyruvic acid are then sent to the main control unit 172.

[0033] Next, specific operational aspects of the biological information detecting method executed in the biological information detecting device according to the first embodiment will be described with reference to FIGS.

[0034] Fig. 5 is a flowchart showing an outline of the biological information detection method according to the first embodiment. Also, Figs. 6A to 6C are plan and partial front views showing an outline of the operational procedure for irradiating blood with pulsed laser light in the biological information detection device according to the first embodiment. Also, Fig. 7 is a time series graph showing the relationship between various command signals and measurement data.

[0035] 5, in the biological information detection method executed by the biological information detection device 100 according to the first embodiment, when a start signal Ss corresponding to the start of measurement is input by the user via the input interface 178, first the main control section 172 of the control unit 170 commands the quantity calculation section 174 to start receiving the detection signal Sd from the light-receiving sensor 160 (step S101). As a result, the quantity calculation section 174 continuously receives and temporarily stores the detection signal Sd from the light-receiving sensor 160 as time-series data until the operation shown in the flowchart is completed.

[0036] Next, the main controller 172 outputs a relative movement signal Sm to the transport mechanism 140 and the sample holding mechanism 150 based on a predetermined measurement program (step S102), thereby determining the position and focal length at which the pulsed laser light LB is irradiated onto the blood BL.

[0037] Next, the main control unit 172 outputs a first oscillation signal S1o and a second oscillation signal S2o to the first laser oscillator 110 and the second laser oscillator 120 to emit the first pulse laser beam LB1 or the second pulse laser beam LB2 for a predetermined irradiation time Ton (step S103). In the first laser oscillator 110 that has received the first oscillation signal S1o, the oscillation control unit 112 outputs an on-command signal Son to the drive power supply 113 for the irradiation time Ton, and the first pulse laser beam LB1 adjusted to a predetermined wavelength is emitted. Note that this operation is similarly performed in parallel in the second laser oscillator 120.

[0038] Next, the main control unit 172 determines whether or not irradiation of the pulsed laser light LB has been completed in all measurement ranges defined for the blood BL in the container 152 based on the measurement program (step S104). That is, if it is determined in step S104 that irradiation has been completed in all measurement ranges, the main control unit 172 outputs a calculation signal Se to the quantity calculation unit 174, indicating that measurement of the blood BL has been completed, and proceeds to the subsequent step S105.

[0039] On the other hand, if it is determined in step S104 that irradiation has not been completed in all measurement ranges, the process returns to step S102, and the positioning and irradiation of the pulsed laser beam LB for the unfinished measurement ranges according to the measurement program are repeatedly performed, thereby detecting the measurement target substance MM in all ranges (regions) to be measured of the blood BL contained in the container 152.

[0040] 6A to 6C show a specific example of the operational procedure from step S102 to step S104. That is, as shown in Fig. 6A, blood BL is contained in a container 152 placed on a light-receiving sensor 160 having a sensing surface on its upper surface, and a plurality of rectangular regions C are defined in the blood BL, each having a length and width corresponding to the focal diameter (spot diameter) of a focal point FP of pulsed laser light LB.

[0041] Then, for the plurality of rectangular regions C defined as above, the measurement program further defines an irradiation start position Ps and an irradiation end position Pe of the pulsed laser beam LB, and specifies a scanning path for scanning in the X and Y directions between the irradiation start position Ps and the irradiation end position Pe. As an example, the determination in step S104 of the flowchart shown in Fig. 5 is made based on whether the current irradiation position (focus point FP) coincides with the irradiation end position Pe on the scanning path.

[0042] Next, the relationship between the presence or absence of the measurement target substance MM at the irradiation position (focus point FP) of the pulsed laser light LB and the detection signal from the light-receiving sensor 160 will be described below. For example, as shown in Fig. 6B, if the measurement target substance MM is not present at the focus point FP of the irradiated pulsed laser light LB or on its extension, the pulsed laser light LB passes through the blood BL and the container 152, and transmitted light TB equivalent to the output of the irradiated pulsed laser light LB is detected at the light-receiving point DP of the light-receiving sensor 160.

[0043] On the other hand, as shown in Fig. 6C, when the substance to be measured MM is present at the focal point FP of the irradiated pulsed laser beam LB or on an extension thereof, the first pulsed laser beam LB1 or the second pulsed laser beam LB2 irradiated as the pulsed laser beam LB is absorbed or reflected by lactic acid or lactate and pyruvic acid in the substance to be measured MM, and transmitted light TB having a lower output than the output of the irradiated pulsed laser beam LB is detected at the light-receiving point DP of the light-receiving sensor 160. Note that Fig. 6C illustrates an example in which the substance to be measured MM is larger than the focal diameter of the focal point FP of the pulsed laser beam LB, but a similar tendency is observed even when the substance to be measured MM is smaller than the focal diameter.

[0044] Next, the quantity calculation unit 174, which has received the calculation signal Se from the main control unit 172, extracts first-section data D1 corresponding to the first pulse laser beam LB1 and second-section data D2 corresponding to the second pulse laser beam LB2 by extracting sections of the detection signal Sd from the light-receiving sensor 160 corresponding to the sections during which the first oscillation signal S1o and the second oscillation signal S2o were received from the main control unit 172, as shown in FIG. 7 (step S105). This allows narrowing down the data in the detection signal Sd to only those sections corresponding to the irradiation time T1on during which the first pulse laser beam LB1 was irradiated or the irradiation time T2on during which the second pulse laser beam LB2 was irradiated (i.e., noise during detection can be reduced). Here, the irradiation time T1on and non-irradiation time T1off of the first oscillation signal S1o are collectively defined as one period T (the same applies to the relationship between the second oscillation signal S2o and one period T).

[0045] Next, the quantity calculation unit 174 calculates the quantities of lactic acid or lactate and pyruvic acid in the measurement target substance MM relative to the blood BL based on the extracted first section data D1 and second section data D2. Specifically, the first section data D1 extracted in step S105 includes, as an example, output values ​​at two levels: reference data D1s (the state shown in FIG. 6B) when the measurement target substance MM is not detected (non-detection section Tn), and detection data D1d (the state shown in FIG. 6C) when the measurement target substance MM is detected (detection section T1d).

[0046] At this time, it can be determined that the greater the absolute value of the difference ΔD1 between the reference data D1s and the detection data D1d, the greater the detected amount of the measurement target substance MM. After measuring all of the target measurement ranges, the amount calculation unit 174 adds up the number of detection data D1d in the entire section data D1, and outputs this as the "amount" of the measurement target substance MM to the main control unit 172, and then ends the operation (step S106).

[0047] On the other hand, the extracted second section data D2 includes, as an example, output values ​​at two levels: reference data D2s when the target substance MM is not detected (non-detection section Tn), and detection data D2d when the target substance MM is detected (detection section T2d). Therefore, as with the first section data D1, it can be determined that the greater the absolute value of the difference ΔD2 between the reference data D2s and the detection data D2d, the greater the amount of the target substance MM detected.

[0048] The amount of the measurement target substance MM may be calculated as a ratio to the total amount rather than as an integrated number. Also, thresholds may be set for the difference ΔD1 or ΔD2 between the reference data and the detected data, and values ​​exceeding the predetermined thresholds may be determined to have been "detected."

[0049] By having the above-mentioned configuration, the bioinformation detection device and bioinformation detection method according to the first embodiment are configured to output an oscillation command to two laser oscillators of wavelengths suitable for detecting lactic acid or lactate salts and pyruvic acid to emit pulsed laser light at a constant period, extract the detection signal from the light receiving sensor at a time corresponding to the constant period as section data corresponding to the laser light of each wavelength, and calculate the amount of lactic acid or lactate salts and pyruvic acid in the blood based on the section data, thereby making it possible to obtain the concentrations of lactic acid and pyruvic acid contained in the blood independently of each other.

[0050] <Second embodiment> Next, a description will be given of an implementation of a biological information detection device and a biological information detection method according to a second embodiment, which is another example of the present invention, using Figures 8A to 8C and 9. In the second embodiment, in the schematic diagrams shown in Figures 1 to 7, components that can adopt the same or common configurations as those in the first embodiment are assigned the same reference numerals, and repeated description of these components will be omitted.

[0051] 8A to 8C are plan views and partial front views showing an outline of an operational procedure for irradiating blood with pulsed laser light in a biological information detecting device according to the second embodiment, and Fig. 9 is a flowchart showing an outline of a biological information detecting method according to the second embodiment.

[0052] In the biological information detecting device 100 according to the second embodiment, instead of the measurement method using a container 152 for storing blood BL in the first embodiment, a measurement method is used in which a pulsed laser beam LB for direct measurement is irradiated onto blood vessels or the like while the blood BL is flowing inside a living organism such as a human being. That is, as shown in Fig. 8A, for example, in a human body, a terminal part (such as a finger 240) through which the irradiated pulsed laser beam LB is relatively easily transmitted is placed on a light receiving sensor 160 having a sensing surface on its upper surface, and the pulsed laser beam LB is irradiated onto the finger 240.

[0053] At this time, if the measurement target substance MM is not present at the focal point FP of the irradiated pulsed laser light LB or on its extension, as shown in FIG. 8B for example, the pulsed laser light LB passes through the finger 240 including the blood vessels 242, and transmitted light TB corresponding to the output of the irradiated pulsed laser light LB is detected at the light-receiving point DP of the light-receiving sensor 160.

[0054] On the other hand, as shown in Fig. 8C, when the measurement target substance MM is present at the focal point FP of the irradiated pulsed laser beam LB or on an extension thereof, the pulsed laser beam LB is absorbed or reflected by lactic acid or lactate and pyruvic acid in the measurement target substance MM, as in the first embodiment, and transmitted light TB having a lower output than the output of the irradiated pulsed laser beam LB is detected at the light-receiving point DP of the light-receiving sensor 160. Note that Fig. 8C also shows a similar tendency, as in the first embodiment, even when the measurement target substance MM is smaller than the focal diameter of the focal point FP of the pulsed laser beam LB.

[0055] In this state of arrangement, pulsed laser light LB is irradiated for a predetermined time by on / off control at a constant cycle T, while receiving a detection signal Sd from the light-receiving sensor 160. As a result, instead of scanning and measuring the measurement area of ​​the blood BL in the container 152 as in the first embodiment, it is possible to measure time-series data of the blood BL as continuously flowing blood without moving the optical axis of the pulsed laser light LB (i.e., the irradiation mechanism 130).

[0056] 9, in the biological information detection method according to the second embodiment, when a start signal Ss corresponding to the start of measurement is input by the user via the input interface 178, the main control section 172 of the control unit 170 first commands the quantity calculation section 174 to start receiving the detection signal Sd from the light-receiving sensor 160 (step S201). As a result, similar to the first embodiment, the quantity calculation section 174 continuously receives and temporarily stores the detection signal Sd from the light-receiving sensor 160 as time-series data until the operation shown in the flowchart is completed.

[0057] Next, the main control unit 172 outputs a first oscillation signal S1o and a second oscillation signal S2o to the first laser oscillator 110 and the second laser oscillator 120 based on a predetermined measurement program, causing the first laser oscillator 110 and the second laser oscillator 120 to emit pulsed laser light LB for a predetermined irradiation time Ton (step S202). In the first laser oscillator 110 that has received the first oscillation signal S1o, the oscillation control unit 112 outputs an on-command signal Son to the drive power supply 113 for the irradiation time Ton, as in the first embodiment, and pulsed laser light LB adjusted to a predetermined wavelength is emitted. Note that this operation is similarly performed in parallel in the second laser oscillator 120.

[0058] Next, the main control unit 172 determines whether the irradiation of the pulsed laser light LB at the constant period T has been completed for a predetermined number of cycles based on the measurement program (step S203). That is, if it is determined in step S203 that the irradiation for the predetermined number of cycles has been completed, the main control unit 172 outputs a calculation signal Se to the quantity calculation unit 174, indicating that the measurement of the blood BL has been completed, and proceeds to the subsequent step S204.

[0059] On the other hand, if it is determined in step S203 that the irradiation for the predetermined number of cycles has not been completed, the process returns to step S202 and the irradiation of the pulsed laser light LB for one cycle is repeated, thereby executing the operation of detecting the measurement target substance in the blood (blood) BL continuously flowing through the blood vessels 242 of the finger 240 for a predetermined time.

[0060] Next, similarly to the first embodiment, the quantity calculation unit 174, which has received the calculation signal Se from the main control unit 172, extracts the first section data D1 and the second section data D2 by cutting out sections of the detection signal Sd from the light receiving sensor 160 that respectively correspond to sections during which the first oscillation signal S1o and the second oscillation signal S2o from the main control unit 172 were received (step S204). This makes it possible to narrow down the data to only those sections of the detection signal Sd during which the first pulse laser beam LB1 and the second pulse laser beam LB2 were irradiated, respectively.

[0061] Next, the quantity calculation unit 174 calculates the quantities of lactic acid or lactate and pyruvic acid in the measurement target substance MM relative to the blood BL based on the extracted first interval data D1 and second interval data D2, as in the first embodiment. Then, the quantity calculation unit 174 outputs the calculated quantities of lactic acid or lactate and pyruvic acid to the main control unit 172, and ends the operation (step S205).

[0062] By being provided with the above-described configuration, the biological information detection device and biological information detection method according to the second embodiment have the effects described in the first embodiment, in addition to the effects described in the first embodiment, since the method uses a technique in which blood, which is a typical example of blood, is directly irradiated with a pulsed laser beam for measurement onto blood vessels in a finger or the like while the blood is flowing inside a living organism such as a human, there is no need to obtain blood in advance from the human body, etc., and the burden during measurement can be reduced. Furthermore, since the step of moving the pulsed laser beam relative to a container containing the blood to be measured is not required, the overall measurement time can also be shortened.

[0063] <Third embodiment> Next, a biological information detection device and a biological information detection method according to a third embodiment, which is yet another example of the present invention, will be described with reference to Figures 10A to 10C, 11, and 12. In the third embodiment, in the schematic diagrams shown in Figures 1 to 9, components that can employ the same or common configurations as those in the first and second embodiments are assigned the same reference numerals, and repeated description of these components will be omitted.

[0064] 10A to 10C are plan and partial front views showing an outline of an operational procedure for irradiating blood with pulsed laser light in a biological information detecting device according to the third embodiment. Also, Fig. 11 is a time series graph showing the relationship between various command signals and measurement data. Furthermore, Fig. 12 is a partial cross-sectional view showing an outline of a measurement unit according to a modified example of the biological information detecting device according to the third embodiment.

[0065] In the biological information detecting device 100 according to the third embodiment, a method of measuring reflected light RB of a measurement target substance MM contained in the blood BL is used, as opposed to the measurement method in the first embodiment in which transmitted light TB from the blood BL is detected by a light receiving sensor 160. That is, as shown in Fig. 10A, blood BL is contained in a container 152 placed on a sample holding mechanism 150, and a pulsed laser beam LB is irradiated onto a predetermined measurement range of the blood BL, as in the first embodiment.

[0066] At this time, in the biological information detection device 100 according to the third embodiment, the reflected light RB reflected by the measurement target substance MM contained in the blood BL is detected by the light-receiving sensor 360 attached to the irradiation mechanism 130. That is, for example, as shown in Fig. 10B, if the measurement target substance MM is not present at the focal point FP of the irradiated pulsed laser light LB or on its extension, the pulsed laser light LB passes through the blood BL and the container 152, and therefore the light-receiving sensor 360 detects only a detection value based on the amount of light around the device.

[0067] On the other hand, as shown in Fig. 10C, when the measurement target substance MM is present at the focal point FP of the irradiated pulsed laser beam LB or on an extension thereof, the pulsed laser beam LB is absorbed or reflected by the measurement target substance MM, and reflected light RB, which is part of the output of the irradiated pulsed laser beam LB, is detected at the light-receiving point DP of the light-receiving sensor 360. Note that Fig. 10C shows the same tendency even when the measurement target substance MM is smaller than the focal diameter of the focal point FP of the pulsed laser beam LB, as in the first embodiment.

[0068] 11 , in the biological information detecting device 100 according to the third embodiment, a detection signal Sd representing a detection value of a predetermined light amount is received in a section in which the light receiving sensor 360 detects the reflected light RB. Then, similar to the first embodiment, the quantity calculation unit 174 extracts first section data D1 and second section data by cutting out sections of the detection signal Sd corresponding to sections in which the first oscillation signal S1o and the second oscillation signal S2o were received from the main control unit 172. This makes it possible to narrow down the data in the detection signal Sd to only those sections in which the first pulsed laser beam LB1 and the second pulsed laser beam LB2 were irradiated, respectively, similar to the first embodiment.

[0069] Next, the quantity calculation unit 174 calculates the quantities of lactic acid or lactate and pyruvic acid in the measurement target substance MM relative to the blood BL based on the extracted first section data D1 and second section data D2. Specifically, the extracted first section data D1 includes, as an example, output values ​​at two levels: reference data D1s when the measurement target substance MM is not detected (non-detection section Tn), and detection data D1d when the measurement target substance MM is detected (detection section Td).

[0070] At this time, as in the first embodiment, it can be determined that the greater the absolute value of the difference ΔD between the reference data D1s and the detection data D1d, the greater the detected amount of the measurement target substance MM. Therefore, after measuring all of the target measurement ranges, the amount calculation unit 174 adds up the number of detection data D1d in the entire first section data D1, and outputs the calculation result to the main control unit 172 as the "amount" of the measurement target substance MM.

[0071] On the other hand, the extracted second section data D2 includes, for example, output values ​​at two levels: reference data D2s when the target substance MM is not detected (non-detection section Tn), and detection data D2d when the target substance MM is detected (detection section T2d). Therefore, as with the first section data D1, it can be determined that the greater the absolute value of the difference ΔD2 between the reference data D2s and the detection data D2d, the greater the amount of the target substance MM detected.

[0072] As described above, in the biological information detecting device 100 according to the third embodiment, the reflected light RB of the pulsed laser beam LB from the substance to be measured MM is detected, and this is extracted as the first section data D1 and the second section data D2 corresponding to the first pulsed laser beam LB1 and the second pulsed laser beam LB2, thereby making it possible to individually calculate the amounts of lactic acid or lactate and pyruvic acid in the substance to be measured MM. In this way, because detection and calculation are performed using the reflected light RB of the pulsed laser beam LB, a more compact measuring unit configuration can be adopted as a modification of the third embodiment.

[0073] 12, an example of a measurement unit 380 is one that integrally includes a cylindrical container 382 that contains a part of a living organism, such as a finger 240, including blood vessels through which blood BL flows, an irradiation mechanism 130 that irradiates pulsed laser light LB toward an internal space S of the container 382, ​​and a light-receiving sensor 360 that detects reflected light of the pulsed laser light LB. This allows the amount of light detected by the light-receiving sensor 360 to be minimized with respect to the amount of light associated with the ambient environment of the measurement unit 380, thereby further improving measurement accuracy.

[0074] By being configured as described above, the bioinformation detection device and bioinformation detection method according to the third embodiment can, in addition to the effects described in the first embodiment, further improve measurement accuracy by using a method of measuring reflected light from the substance to be measured contained in blood, thereby minimizing the detection of the amount of light associated with the surrounding environment.

[0075] The present invention is not limited to the above-described embodiments, and can be modified as appropriate without departing from the spirit and scope of the invention. Any component of the embodiments can be modified or omitted within the scope of the invention. For example, the specific examples shown in the first to third embodiments can be applied by combining their respective features. [Explanation of symbols]

[0076] 100 Biometric information detection device 110 First laser oscillator 112 Oscillation control section 113 Drive power supply 114 Support part 115a, 115b laser light source 116 Condenser Lens 117 Wavelength adjustment section 118 Transmission Line 120 Second laser oscillator 128 Transmission Line 130 Irradiation mechanism 131a, 131b connectors 132 Beam Splitter 133, 134, 135 Mirror 136 Condenser Lens 137 Window components 140 Transport mechanism 150 Sample holding mechanism 152 Container 160 Light receiving sensor 170 Control Unit 172 Main control unit 174 Volume calculation section 176 Display section 178 Input Interface 240 fingers 242 Blood vessels 360 Light receiving sensor 380 measuring units 382 Storage Unit

Claims

1. a first laser oscillator that oscillates a first pulsed laser beam having an appropriate wavelength corresponding to detection of lactic acid or a lactate salt; a second laser oscillator that oscillates a second pulsed laser beam having an appropriate wavelength corresponding to detection of pyruvic acid; an irradiation mechanism that irradiates blood containing the lactic acid or lactate and the pyruvic acid with the first pulsed laser light and the second pulsed laser light; a light receiving sensor that receives detection laser light output from the blood; A control unit for controlling the operation of each component; Including, The control unit outputs an oscillation command to the first laser oscillator and the second laser oscillator to oscillate the first pulsed laser light and the second pulsed laser light, respectively, at a constant cycle, extracts a detection signal from the light receiving sensor as section data at a time corresponding to the constant cycle, and calculates the amounts of the lactic acid or lactate salt and the pyruvic acid in the blood based on the section data. Biometric information detection device.

2. The optimum wavelength of the first pulsed laser beam is 1480 nm, and the optimum wavelength of the second pulsed laser beam is 1462 nm. The biological information detection device according to claim 1 .

3. The first pulsed laser light and the second pulsed laser light are both irradiated toward the flowing blood. The biological information detection device according to claim 1 .

4. The light receiving sensor is configured to receive reflected light of the first pulsed laser light and the second pulsed laser light from the blood. The biological information detection device according to claim 1 .

5. A biological information detection method comprising: irradiating blood containing lactate or lactate and pyruvic acid with a first pulsed laser light having an appropriate wavelength for detecting lactate or lactate salts and a second pulsed laser light having an appropriate wavelength for detecting pyruvic acid; receiving detection laser light output from the blood with a light receiving sensor; and acquiring amounts of lactate or lactate salts and pyruvic acid in the blood, The first pulsed laser light and the second pulsed laser light are each oscillated at a constant cycle, a detection signal from the light receiving sensor is cut out as section data at a time corresponding to the constant cycle for each of the appropriate wavelengths of the first pulsed laser light and the second pulsed laser light, and the amounts of the lactic acid or lactate salt and the pyruvic acid in the blood are calculated based on the section data. A method for detecting biological information.

6. The optimum wavelength of the first pulsed laser beam is 1480 nm, and the optimum wavelength of the second pulsed laser beam is 1462 nm. The biological information detecting method according to claim 5 .

7. The first pulsed laser light and the second pulsed laser light are both irradiated toward the flowing blood. The biological information detecting method according to claim 5 or 6.

8. The detection laser light is a reflected light of the first pulsed laser light and a reflected light of the second pulsed laser light from the blood. The biological information detecting method according to claim 5 or 6.

Images