JP2019170542A - Biometric measurement device and program - Google Patents

Abstract

To provide a technology to switch a measurement condition during measurement in order to acquire different pieces of information on a living body.SOLUTION: A measurement device includes: a spectral sensor including spectral means for dispersing a reflection light from a living body, and light reception means that includes a plurality of pixels, each of the plurality of pixels receiving a light including a predetermined wavelength dispersed by the spectral means; generation means for generating a biological signal from a light reception result of a first pixel of the light reception means; determination means for determining a cycle of the biological signal; first detection means for detecting a feature amount of the biological signal in each cycle of the biological signal; second detection means for detecting biological information from a light reception result of a second pixel of the light reception means; determination means for determining a first measurement condition and a second measurement condition; and setting means for determining an ending timing of the detection by the second detection means in each cycle of the biological signal, setting the first measurement condition to the spectral sensor until the first detection means detects a feature amount, and setting the second measurement condition to the spectral sensor from the detection of the feature amount by the first detection means to an ending timing.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a biological measurement apparatus and program.

  2. Description of the Related Art There are known measuring apparatuses that detect biological information by irradiating a part of a living body with light and detecting the amount of reflected light or transmitted light from the living body. The biological information is, for example, various physiological / anatomical information emitted by the living body, such as the pulse rate and the degree of vascular hardening. For example, the pulse rate can be detected based on a pulse wave signal indicating fluctuations in the amount of reflected or transmitted light accompanying blood movement in the blood vessel. For example, the degree of hardening of the blood vessel can be detected based on a feature point of an acceleration pulse wave signal (hereinafter simply referred to as an acceleration signal) obtained by differentiating the pulse wave signal twice.

  Patent Document 1 discloses a pulse wave measurement device that is an example of a biological information measurement device. According to Patent Document 1, the pulse wave measuring device irradiates a fingertip with a light beam, and detects a pulse wave from a temporal variation in the amount of reflected light. Patent Document 2 discloses a configuration for acquiring a plurality of biological information using a light receiving unit having a plurality of light receiving elements. Patent Document 3 discloses a configuration that reduces the power consumption of the measuring device by switching the operation mode of the light receiving unit based on the timing of the feature point of the detection signal detected by the light receiving unit. Furthermore, patent document 4 is disclosing the structure which measures a carboxyhemoglobin density | concentration.

Japanese Patent Laid-Open No. 2004-046767 JP 2013-150772 A JP 2017-108905 A Japanese Patent Laid-Open No. 2015-000127

  When a plurality of pieces of biological information are detected, appropriate measurement conditions may differ depending on the detected biological information. The measurement conditions include, for example, the light emission intensity of the light source, the light reception time of the light receiving sensor, and the like. Therefore, when a plurality of pieces of biological information are detected in parallel using a common light source and light receiving sensor, it is necessary to switch measurement conditions during measurement. When the measurement condition is switched during the detection of the biological information, the detection signal output from the light receiving sensor changes, which affects the detection of the biological information. In addition, when measurement is interrupted to switch measurement conditions, the detection time of biological information becomes longer.

  Patent Document 2 discloses a configuration for detecting a plurality of pieces of biological information, but does not disclose switching measurement conditions in order to detect a plurality of pieces of biological information. Patent Document 3 discloses a configuration that aims to reduce power consumption, does not switch measurement conditions in order to detect a plurality of pieces of biological information, and avoids the influence of fluctuations in detection signals caused by this switching. Not.

  The present invention provides a technique for switching measurement conditions during measurement in order to acquire different information of a living body.

  According to one aspect of the present invention, the measuring device uses a light source that emits light toward the measurement position, reflected light from the living body at the measurement position, or transmitted light that has passed through the living body at the measurement position. A spectroscopic sensor including a spectroscopic means for performing spectroscopic analysis according to the above, and a plurality of pixels, and each pixel of the plurality of pixels includes a light receiving means for receiving light including a predetermined wavelength spectrally separated by the spectroscopic means, A generating unit that generates a biological signal from a light reception result of the first pixel of the light receiving unit, a determining unit that determines a cycle of the biological signal, and a first that detects a feature amount of the biological signal in each cycle of the biological signal. A detection means; a second detection means for detecting biological information from the light reception result of the second pixel of the light receiving means; a first measurement condition for generating the biological signal; and the biological information by the second detection means. Second measurement condition for detection The determination means for determining, and the end timing of the detection by the second detection means in each cycle of the biological signal are determined, and the first measurement condition is set as the spectral value until the first detection means detects the feature amount. And setting means for setting the second measurement condition in the spectroscopic sensor from the time when the first detection means detects the feature amount to the end timing.

  According to the present invention, the measurement conditions can be switched during measurement in order to acquire different information of the living body.

The functional block diagram of the measuring device by one Embodiment. The block diagram of the measuring device by one Embodiment. The figure which shows the spectrum of the white light source by one Embodiment, and the structure of a line sensor. The flowchart of the detection process of the biometric information by one Embodiment. The figure which shows the biomedical signal and acceleration signal by one Embodiment, and a feature point. Explanatory drawing of the detection process by one Embodiment. The flowchart of the detection process of the biometric information by one Embodiment. The figure which shows the external appearance of the measuring apparatus by one Embodiment.

  Hereinafter, exemplary embodiments of the present invention will be described with reference to the drawings. In addition, the following embodiment is an illustration and does not limit this invention to the content of embodiment. In the following drawings, components that are not necessary for the description of the embodiments are omitted from the drawings.

<First embodiment>
FIG. 8 is a perspective view of the measuring apparatus 1 according to the present embodiment. 8A shows a state where the shutter member 102 covers the opening 500, and FIG. 8B shows a state where the shutter 500 is moved to the retracted position and the opening 500 is exposed. Yes. The opening 500 is covered with a transparent cover 400 that prevents foreign matter from falling into the housing 110. The housing 110 is provided with a groove-shaped guide rail 116 along the X direction in FIG. Further, the guide portion 131 of the guide member 103 is fitted into the guide rail 116. As a result, the guide member 103 and the shutter member 102 can move within the range in which the guide rail 116 is provided in the X direction. A spring is attached to the guide portion 131 of the guide member 103 in the housing 110. The guide member 103 stops at the position shown in FIG. 8A in a state in which no force is applied to the guide member 103 from the outside by the spring force. When the user measures biometric information, the user pushes the finger receiving portion 320 of the guide member 103 in the X direction with a finger, and slides the guide member 103 and the shutter member 102 in the X direction. The measuring apparatus 1 is configured such that when the guide member 103 and the shutter member 102 are pushed by a finger to a position limited by the guide rail 116, the tip portion of the finger covers the opening 500. In this state, the white light source 21 (FIG. 2) irradiates the finger with light from the inside of the housing 110 through the opening 500, and the line sensor 24 (FIG. 2) inside the housing 110 transmits the reflected light. Receive light.

  The housing 110 is provided with a pressing member 105 and a pressing spring 151 that are rotatably held by the bearing portion 119. The pressing spring 151 applies a force toward the opening 500 to the pressing member 105. The pressing member 105 is provided with a pressing rib 152, and the shutter member 102 is provided with a pressed rib 123. In the state of FIG. 8A, the pressing rib 152 contacts the pressed rib 123, and thereby the shutter member 102 is urged against the upper surface of the housing 110. A white reference plate is provided on the surface of the shutter member 102 on the opening 500 side. The white reference plate is used for calibration of the white light source 21 and the line sensor 24 inside the housing 110. The shutter member 102 prevents light from leaking from the housing 110 through the opening 500 during calibration. The pressing member 105 also has a role of stabilizing the measurement target fingertip at the position of the opening 500 at the time of measurement.

  FIG. 2 is a configuration diagram of hardware arranged in the housing 110 of the measuring apparatus 1. The CPU 50 is a control unit that controls the entire measurement apparatus 1. The CPU 50 executes various controls described later based on the program stored in the ROM 51. The CPU 50 stores in the RAM 52 data used when executing various controls and data that needs to be temporarily stored. The CPU 50 can communicate with the ROM 51, the RAM 52, the I / O port 54, the AD conversion circuit 55, and the external communication circuit 56 via the bus 53. The light source drive circuit 60 controls the light emission of the white light source 21. Further, the CPU 50 can control the light emission intensity of the white light source 21 by controlling the light source driving circuit 60 via the I / O port 54. Further, the CPU 50 can set the charge accumulation time of the line sensor 24 via the I / O port 54. As will be described later, the line sensor 24 receives the reflected light of the light emitted from the white light source 21 via the condenser lens 22 and the diffraction grating 23, and outputs a voltage corresponding to the amount of received light to the AD conversion circuit 55. The CPU 50 acquires a voltage corresponding to the amount of received light output from the line sensor 24 via the AD conversion circuit 55. Further, the CPU 50 is configured to be able to communicate with the external device 30 via the external communication circuit 56. The condenser lens 22, the diffraction grating 23, and the line sensor 24 constitute a spectrocolorimeter (spectral sensor). Alternatively, the white light source 21, the condensing lens 22, the diffraction grating 23, and the line sensor 24 constitute a spectroscopic sensor.

  FIG. 1 is a block diagram for explaining the operation of the measuring apparatus 1 in the present embodiment. The CPU 50 executes the program stored in the ROM 51 to cooperate with the I / O port 54, the light source driving circuit 60, the AD conversion circuit 55, the external communication circuit 56, the ROM 51, and the RAM 52, and the control unit 10 in FIG. Function as. The light emission control unit 11 corresponds to the CPU 50 and the light source drive circuit 60, adjusts the light emission intensity of the white light source 21, and controls the light emission of the white light source 21. The white light source 21 has a light emission wavelength distribution over the entire visible light. As the white light source 21, for example, tungsten light, white LED, RGB (red, green, blue) three-color LED, or the like can be used. In the present embodiment, the white light source 21 is a white LED using tungsten light. FIG. 3A shows the relative intensity (luminance) for each wavelength of the white light source 21 used in the present embodiment.

  As shown in FIG. 1, the light 70 emitted from the white light source 21 passes through the opening 500 of the housing 110 at an angle of about 45 degrees with respect to the normal direction, and is the measurement object 90 at the measurement position. Irradiate the fingertip. This irradiation light becomes scattered light 71 corresponding to the light absorption characteristics of the measurement object 90. A part of the scattered light 71 is converted into parallel light 72 by the condenser lens 22 and enters the diffraction grating 23 at an incident angle of 90 degrees. The diffraction grating 23 separates incident light according to the wavelength. The dispersed light 73 dispersed is incident on each pixel of the line sensor 24. Each pixel of the line sensor 24 outputs a voltage corresponding to the received light amount of the incident dispersed light 73 to the received light amount detection unit 12. FIG. 3B is a schematic diagram of the line sensor 24. The line sensor 24 according to the present embodiment has 120 pixels necessary for detecting visible light having a wavelength of about 400 nm to about 1000 nm in units of 5 nm. In the present embodiment, the measuring apparatus 1 is adjusted and assembled so that the first pixel of the line sensor 24 detects light including a wavelength of about 400 nm and the 120th pixel of about 1000 nm. The received light amount detection unit 12 corresponds to the CPU 50, the AD conversion circuit 55, and the I / O port 54. In practice, the AD conversion circuit 55 converts the voltage of each pixel output from the line sensor 24 into, for example, a 12-bit digital value, and the CPU 50 performs AD conversion on the digital value indicating the amount of light received by each pixel. Obtained from the circuit 55. The line sensor 24 of the present embodiment is a charge storage type, and outputs a voltage signal for each pixel according to the amount of dispersed light incident during a predetermined storage time. The accumulation time in the line sensor 24 is set in the line sensor 24 via the I / O port 54 by the received light amount detection unit 12, more specifically, the CPU 50.

  The first biological signal generation unit 13 generates a first biological signal based on a light reception result of a predetermined pixel, that is, a value indicating the amount of received light. In the present embodiment, the first finger signal of the living body is the measurement object 90, and the first living body signal is generated based on the amount of light received by the 38th pixel that detects the wavelength of about 590 nm. This first biological signal is also referred to as a fingertip volume pulse wave signal. The wavelength of about 590 nm used for generation of the first biological signal is a wavelength at which the amount of light absorbed by hemoglobin in blood is relatively large.

  The second biological signal generation unit 19 changes the received light amount of each of the plurality of pixels of the line sensor 24 with respect to the received light amount of the 52nd pixel that detects the wavelength of about 660 nm and the 108th pixel that detects the wavelength of about 940 nm. 2 is generated and output to the biological information detection unit 20. The biological information detection unit 20 determines the percutaneous arterial blood oxygen saturation (SpO2) based on the second biological signal. SpO2 indicates in percentage how much hemoglobin in arterial blood is bound to oxygen. In the detection of SpO2, the biological information detection unit 20 obtains the value R of SpO2 as R = P660 / P940. Here, P660 is the amount of received light of the 52nd pixel (about 660 nm), and P940 is the amount of received light of the 108th pixel (about 940 nm). SpO2 is obtained from the received light amount of the 52nd pixel and the received light amount of the 108th pixel at the same timing. The biological information detection unit 20 determines SpO2 by applying the value R obtained based on the second biological signal to the calibration curve of the value R and SpO2 created in advance.

  The external communication unit 17 corresponds to the external communication circuit 56 and communicates with the external device 30. The external device 30 instructs the measurement apparatus 1 to start measurement and end measurement. In addition, the measuring apparatus 1 uses the first biological signal, a signal obtained by differentiating the first biological signal multiple times, the period C of the first biological signal, the feature point of the first biological signal, the determined SpO2, and the like. 30. The external device 30 can calculate the pulse value from the period C of the first biological signal. Furthermore, the external device 30 can determine the degree of hardening of the blood vessel based on the feature points of the first biological signal and their values. The external device 30 is, for example, a personal computer or a tablet terminal. The communication with the external device 30 may be wired or wireless. The condition changing unit 14 will be described later. Instead of determining SpO2 in the control unit, the second biological signal may be transmitted to the external device 30, and the external device 30 may determine SpO2.

  FIG. 4 is a flowchart of the biometric information detection process. When the measurement apparatus 1 receives the measurement start instruction from the external device 30, the measurement apparatus 1 determines the measurement conditions A and B in S100. The measurement conditions are, for example, the light emission intensity of the white light source 21 and the charge accumulation time (light reception time) of the line sensor 24. Further, the measurement condition A is a measurement condition when generating the first biological signal, and the measurement condition B is a measurement condition when generating the second biological signal.

  First, determination of the measurement condition A will be described. For example, the light emission control unit 11 causes the white light source 21 to emit light with a predetermined light emission intensity, and the light reception amount detection unit 12 detects the light reception amount of the 38th pixel used for generating the first biological signal for a predetermined period. Then, the control unit 10 determines the light emission intensity and / or the white light source 21 so that the maximum value (peak value) of the received light amount detected in the predetermined period is near the maximum value of the voltage range detectable by the AD conversion circuit 55. The charge accumulation time of the line sensor 24 is determined, and this is defined as measurement condition A. The predetermined period may be one cycle or more of the fingertip volume pulse wave signal that is the first biological signal to be generated, and may be, for example, 2 seconds. Note that the emission intensity of the white light source 21 for determining the measurement condition A in S100 is determined in advance. Then, the control unit 10 determines the measurement condition A based on the light emission intensity and the maximum value of the light reception amount of the 38th pixel.

  Subsequently, determination of the measurement condition B will be described. As described above, the second biological signal is generated by the received light amount of the 52nd pixel (about 660 nm) and the received light amount of the 108th pixel (about 940 nm). Therefore, similarly to the determination of the measurement condition A, the light emission control unit 11 causes the white light source 21 to emit light with a predetermined light emission intensity, and the light reception amount detection unit 12 detects the light reception amounts of the 52nd and 108th pixels for a predetermined period. To do. Then, the control unit 10 determines the light emission intensity and / or the white light source 21 so that the received light amounts of the 52nd and 108th pixels detected in the predetermined period are close to the maximum value of the voltage range detectable by the AD conversion circuit 55. Alternatively, the charge accumulation time of the line sensor 24 is determined, and this is set as the measurement condition B. Measurement conditions A and B can be determined in parallel or individually. It should be noted that the measurement conditions are set so that the maximum amount of light received by the pixels used for the generation of the biological signal is appropriate while changing the light emission intensity of the white light source 21 and / or the charge accumulation time of the line sensor 24 for each predetermined period. The structure to determine may be sufficient.

  The control unit 10 sets the determined measurement condition A in the light emission control unit 11 and the received light amount detection unit 12 in S101. Accordingly, the light emission control unit 11 causes the white light source 21 to emit light with the light emission intensity according to the measurement condition A. Further, the received light amount detection unit 12 sets the charge accumulation time according to the measurement condition A in the line sensor 24. The first biological signal generation unit 13 generates a first biological signal based on the amount of light received at each timing of the 38th pixel, and outputs the first biological signal to the period calculation unit 15 and the feature calculation unit 16. The first biological signal generation unit 13 can generate the first biological signal by directly indicating the received light amount at each timing of the 38th pixel in time series. The first biological signal generation unit 13 divides the amount of light received at each timing of the 38th pixel into a predetermined number, obtains an average value of the predetermined number, and indicates the average value in time series to thereby display the first biological signal. Can be generated. In addition, the first biological signal generation unit 13 can generate a biological signal by a moving average of the amount of received light at a predetermined number of times of the 38th pixel. In addition, it is possible to perform a filter process on a signal indicating the amount of light received at each timing or an average value thereof in time series, and the signal after the filter process can be used as the first biological signal.

  In S102, the period calculation unit 15 determines the period C of the first biological signal based on the extreme value of the first biological signal. For example, the period calculation unit 15 determines the period C of the first biological signal based on the time interval of the local minimum value of the first biological signal. FIG. 5A shows a detection example of the first biological signal and the period C (four times C1 to C4) of the first biological signal. Moreover, the period calculation part 15 can also determine the period of a 1st biological signal based on the time interval of the local maximum value of the acceleration signal which differentiated the 1st biological signal twice. FIG. 5B shows a detection example of the period C (four times C′1 to C′4) of the first biological signal determined from the time interval between the acceleration signal and the local maximum value of the acceleration signal. Yes.

  In S103, the feature calculation unit 16 calculates feature points and values of the first biological signal. In the present embodiment, the first five points of the local maximum value and the local minimum value of the acceleration signal obtained by differentiating the biological signal twice with the start timing of the period C of the first biological signal as a base point are feature points. The start timing of the period C of the first biological signal is the timing of the local minimum value (extreme value) of the first biological signal. FIG. 5C shows an example of five feature points a, b, c, d, and e. Note that the feature calculation unit 16 can also use the local maximum value and the local minimum value of the signal obtained by differentiating the first biological signal four times as the feature points. Further, the number of feature points is not limited to 4, and may be other numbers. More generally, the feature calculation unit 16 can use, as the feature amount, information on the change point of the differential signal obtained by differentiating the first biological signal one or more times.

  The feature calculation unit 16 continues to calculate feature points until all feature points are calculated in S103 and S104. When the feature calculation unit 16 completes the calculation of all feature points, the condition changing unit 14 determines the detection period Q of the second biological signal in S105. FIG. 6 is an explanatory diagram of the detection period Q. The timing Ta in FIG. 6 is the timing when the period calculation unit 15 detects the end of the period C1 of the first biological signal, that is, the local minimum value. In the present embodiment, the period calculation unit 15 detects the local minimum value of the first biological signal by detecting that the amplitude of the biological signal continuously increases for a predetermined time or more. That is, the period calculation unit 15 detects the end time of the period C1 of the first biological signal (the time when the local minimum value is reached) afterwards. The timing Tb in FIG. 6 is the timing when the feature calculation unit 16 completes the calculation of all feature points. Time CX is a predicted time at which the end time of the current cycle C2 is predicted. The condition changing unit 14 estimates the time after the period corresponding to the immediately preceding cycle C1 as the predicted time CX from the start timing of the cycle C2. In addition, it can also be set as the structure which calculates the estimated time CX using the average value of several past periods C instead of the last period C. FIG. Since the cycle of the first biological signal varies, the condition changing unit 14 can use the variation margin Z, which is the variation amount of the first biological signal, for calculating the predicted time CX. In this case, the condition changing unit 14 sets the time earlier by the variation margin Z as the predicted time CX than the time one cycle before the start timing of the cycle C2 or the time after the average value of the past plural cycles. Note that the value of the fluctuation margin Z is stored in the ROM 51 in advance.

  The condition changing unit 14 obtains a timing Tc that is earlier than the predicted time CX by the change time D, and uses the timing Tc as the end timing of the detection period. The condition changing unit 14 sets the period from the timing Tb to the timing Tc as the detection period Q. The change time D is the time from when the measurement condition B is changed to the measurement condition A until the first biological signal is stabilized and thus measurement based on the first biological signal can be performed. For example, when changing the light emission intensity of the white light source 21, the light emission intensity stabilization wait time is included in the change time D. When the received light amount detection unit 12 has a filter circuit such as a low-pass filter, the time based on the time constant of the filter is included in the change time D. Furthermore, when the first biological signal generation unit 13 generates a biological signal by moving average processing of time-series digital values, the time required for the average processing is included in the change time D. In addition, in order to detect the local minimum value of the biological signal, when it is necessary to detect a decrease in the amplitude of the biological signal before the local minimum value is reached for a predetermined period, the condition changing unit 14 detects the predetermined period. The time Y can be used to calculate the timing Tc. In this case, the condition changing unit 14 sets the timing Tc earlier than the predicted time CX by the sum of the change time D and the detection time Y.

  Returning to FIG. 4, the control unit 10 sets the determined measurement condition B in the light emission control unit 11 and the received light amount detection unit 12 in step S <b> 101 in step S <b> 106. The second biological signal generation unit 19 generates a second biological signal and outputs the second biological signal to the biological information detection unit 20 when the change time from the measurement condition A to the measurement condition B elapses after switching to the measurement condition B. As a result, the biological information detection unit 20 determines SpO2 based on the amount of received light of the 52nd pixel (about 660 nm) indicated by the second biological signal and the amount of received light of the 108th pixel (about 940 nm). Since the line sensor 24 outputs the amount of received light for each charge accumulation time, the biological information detection unit 20 determines SpO2 a plurality of times during the detection period Q. In addition, when the detection period Q elapses, the biological information detection unit 20 obtains an average value of a plurality of SpO2 obtained during the detection period.

  After setting the measurement condition B in S106, the control unit 10 waits until the detection period Q elapses in S107. When the detection period Q elapses, the control unit 10 sets the measurement condition A in the light emission control unit 11 and the received light amount detection unit 12 in S108 (timing Tc). In step S109, the control unit 10 determines whether a measurement end instruction is received from the external device 30, and repeatedly performs the processing from step S103 until the measurement end instruction is received. The external communication unit 17 outputs the acceleration signal, the cycle C of the biological signal, the feature point and its value, and the average value of SpO2 to the external device 30 every time one cycle of the first biological signal is completed. To do.

  As described above, while generating the first biological signal and measuring the biological information, the measurement conditions suitable for generating the first biological signal are set. Then, a predicted time CX that is predicted to end the current cycle of the first biological signal is obtained based on one or more previous cycles of the first biological signal. When the feature point is calculated from the first biological signal in the current cycle, the detection period Q of the biological information based on the second biological signal is determined based on the timing and the predicted time CX. At this time, the time required for changing the measurement conditions is taken into consideration. In the detection period Q, measurement conditions suitable for generating the second biological signal are set. With this configuration, it is possible to accurately determine SpO2 from the second biological signal while continuing to calculate the feature points from the first biological signal. That is, measurement conditions suitable for a plurality of pieces of biological information to be detected can be used without interrupting measurement, and the detection accuracy of each piece of biological information can be improved. In the present embodiment, the detection period Q includes a change time necessary for switching from the measurement condition A to the measurement condition B. However, it is also possible to adopt a configuration in which the change time from the measurement condition A to the measurement condition B is excluded from the detection period Q. In this case, the start timing of the detection period Q is the timing after the change time from the measurement condition A to the measurement condition B from the timing Tb.

<Second embodiment>
Next, the second embodiment will be described focusing on the differences from the first embodiment. In the present embodiment, the biological information detection unit 20 determines the carboxyhemoglobin concentration (SpCO) in addition to SpO2. SpCO detects a wavelength of about 620 nm, a pixel number of 44, a pixel number of 52 detecting a wavelength of about 660 nm, a pixel number of 82 detecting a wavelength of about 810 nm, and a wavelength of about 940 nm. It is possible to detect based on the amount of light received by the numbered pixel. A method for determining SpCO based on the amounts of received light of these four wavelengths is described in, for example, Patent Document 4.

  FIG. 7 is a flowchart of the biometric information detection process according to this embodiment. Note that the same steps as those in the flowchart of FIG. 4 are given the same step numbers and description thereof is omitted. When the measurement apparatus 1 receives a measurement start instruction from the external device 30, the measurement apparatus 1 determines measurement conditions A, B, and C in S200. Measurement conditions A and B are the same as in the first embodiment. The measurement condition C is a condition for measuring SpCO, and the maximum value of the amount of light received by a pixel that receives four wavelengths for detecting SpCO is near the maximum value of the voltage range that can be detected by the AD conversion circuit 55. It is a condition to do.

  When the detection period Q is determined in S105, the condition changing unit 14 determines in S201 whether or not the number of measurements is an odd number. When the number of times of measurement is an odd number, the condition changing unit 14 sets the measurement condition B in the light emission control unit 11 and the received light amount detection unit 12 in S106. The second biological signal generation unit 19 generates a second biological signal indicating the amount of light received by the 52nd pixel (about 660 nm) and the 108th pixel (about 940 nm). Thereby, the biological information detection unit 20 determines SpO2 during the detection period Q. On the other hand, if the number of measurements is an even number, the condition changing unit 14 sets the measurement condition C in the light emission control unit 11 and the received light amount detection unit 12 in S202. The second biological signal generation unit 19 includes the 44th pixel (about 620 nm), the 53rd pixel (about 660 nm), the 82nd pixel (about 810 nm), and the 108th pixel (about 940 nm). A second biological signal indicating the amount of received light is generated. Thereby, the biological information detection unit 20 determines SpCO during the detection period Q. In the present embodiment, the external communication unit 17 alternately outputs SpO2 and SpCO to the external device 30 for each cycle of the first generation signal.

  As described above, in the present embodiment, the pixels for generating the second biological signal are switched for each cycle of the first biological signal. With this configuration, the types of biological information to be detected can be increased without degrading the detection accuracy. The biological information detected by the second biological signal can be 3 or more. Also in this case, measurement conditions for each piece of biological information are obtained, and one measurement condition is selected and set sequentially for each cycle of the first biological signal. Information indicating the measurement order of a plurality of types of biological information is stored in the ROM 51 in advance.

  The embodiment has been described by taking the emission intensity of the white light source 21 and the charge accumulation time of the line sensor 24 as examples of measurement conditions. Note that the measurement conditions are not limited to these. For example, the light reception sensitivity (gain) of the line sensor 24 may be used as the measurement conditions. In the second embodiment, only SpO2 or SpCO is detected within one detection period Q. However, according to the time of the detection period Q, one detection period Q can be divided into the first half and the second half, SpO2 can be detected in the first half, and SpCO can be detected in the second half.

  In the above embodiment, the line sensor 24 of the measuring apparatus 1 receives reflected light from the measurement object 90, but may be configured to receive transmitted light. Moreover, the external appearance and mechanical structure of the measuring apparatus 1 of the present invention are not limited to those shown in FIG.

[Other Embodiments]
The present invention supplies a program that realizes one or more functions of the above-described embodiments to a system or apparatus via a network or a storage medium, and one or more processors in a computer of the system or apparatus read and execute the program It is also possible to implement this process. It can also be realized by a circuit (for example, ASIC) that realizes one or more functions.

  21: white light source, 23: diffraction grating, 24: line sensor, 13: first biological signal generation unit, 15: period determination unit, 16: feature amount calculation unit, 19: biological information detection unit, 14: condition change unit, 10: Control unit

Claims (16)

A light source that emits light toward the measurement position, a spectroscopic unit that splits reflected light from the living body at the measurement position or transmitted light that has passed through the living body at the measurement position, and a plurality of pixels Each of the plurality of pixels includes a light receiving means for receiving light including a predetermined wavelength dispersed by the light separating means, and a spectral sensor including:
Generating means for generating a biological signal from the light reception result of the first pixel of the light receiving means;
Determining means for determining a period of the biological signal;
First detection means for detecting a feature quantity of the biological signal in each cycle of the biological signal;
Second detection means for detecting biological information from the light reception result of the second pixel of the light receiving means;
A first measurement condition for generating the biological signal; a determination unit for determining a second measurement condition for detecting the biological information by the second detection unit;
In each cycle of the biological signal, the end timing of detection by the second detection unit is determined, and the first measurement condition is set in the spectral sensor until the first detection unit detects the feature amount, Setting means for setting the second measurement condition in the spectroscopic sensor from the time when the first detection means detects the feature amount to the end timing;
A measuring apparatus comprising:   The said setting means estimates the end time of the cycle of the biological signal based on one or more cycles before the cycle, and determines the end timing based on the estimated end time. The measuring device described in 1.   The measuring apparatus according to claim 2, wherein the setting unit estimates the end time further based on a fluctuation amount of a cycle of the biological signal.   The said setting means sets the timing earlier by the time required for the change from the second measurement condition to the first measurement condition than the estimated end time as the end timing. Measuring device. The determination means determines the period of the biological signal based on the extreme value of the biological signal,
The setting means includes a time required for the change from the second measurement condition to the first measurement condition and a predetermined time required for the determination means to detect the extreme value of the biological signal from the estimated end time. The measuring apparatus according to claim 2, wherein a timing that is earlier by the sum of and the end timing is set as the end timing. The setting means changes to the second measurement condition when the detection means detects the feature amount,
When the second detection unit is changed to the second measurement condition, the second detection unit is configured to perform the second measurement until the end timing after the time required for the change from the first measurement condition to the second measurement condition has elapsed. The measurement apparatus according to claim 1, wherein the biological information is detected based on a light reception result of a pixel. The second pixel is a plurality of pixels of the light receiving means,
The second detection means detects a plurality of types of biological information from light reception results of the plurality of second pixels,
The measurement apparatus according to claim 6, wherein the determination unit determines a plurality of second measurement conditions for detecting each of a plurality of types of biological information.   The measurement according to claim 7, wherein the second detection unit detects each of a plurality of types of biological information from a light reception result of at least one of the plurality of second pixels. apparatus.   The determination means determines the second measurement condition for detecting the biological information based on a peak value of a light reception amount of at least one second pixel used for detection of the biological information. The measuring apparatus according to claim 8. Further comprising holding means for holding information indicating the measurement order of the plurality of types of biological information;
The setting unit selects one of the plurality of types of biological information in accordance with the measurement order in each cycle of the biological signal, and when the detection unit detects the feature amount, the selected biological The measurement apparatus according to claim 7, wherein the measurement apparatus is changed to the second measurement condition for detecting information.   11. The measurement apparatus according to claim 1, wherein the determination unit determines the first measurement condition based on a peak value of a light reception amount of the first pixel.   The first measurement condition and the second measurement condition include at least one of a light emission intensity of the light source, a light reception time of the light receiving unit, and a light reception sensitivity of the light receiving unit. The measuring device according to claim 1.   The measurement apparatus according to claim 1, wherein the biological signal is a pulse wave signal.   The measurement apparatus according to claim 13, wherein the first detection unit uses information of a change point of a signal obtained by differentiating the pulse wave signal at least once as the feature amount.   The first detection means obtains a differential signal obtained by differentiating the pulse wave signal twice or four times, and calculates a predetermined number of extreme values of the differential signal from the timing of the extreme value of the pulse wave signal as the feature amount. The measuring apparatus according to claim 13 or 14, characterized in that: A light source that emits light toward the measurement position, a spectroscopic unit that splits reflected light from the living body at the measurement position or transmitted light that has passed through the living body at the measurement position, and a plurality of pixels Each of the plurality of pixels includes a light receiving means for receiving light including a predetermined wavelength dispersed by the light separating means, and a spectral sensor including:
One or more processors;
When executed on the one or more processors of the measuring device having
In the measuring device,
Setting a first measurement condition in the spectral sensor;
Generating a biological signal from the light reception result of the first pixel of the light receiving means in a state where the first measurement condition is set;
Determining the period of the biological signal;
Detecting a feature value of the biological signal in each cycle of the biological signal;
Determining the end timing of detection of biological information in each cycle of the biological signal;
Detecting a feature value of the biological signal in each cycle of the biological signal, setting a second measurement condition in the spectral sensor;
When the second measurement condition is set in the spectroscopic sensor, detecting the biological information from the light reception result of the second pixel of the light receiving means until the end timing;
A program characterized by having executed.

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