JP7480819B2 - Optical biosensor device, control method, and program - Google Patents

Description

This invention relates to an optical biosensor device, a control method, and a program.

There has been a technology for reducing power consumption in optical biosensors that use a light-emitting element and a light-receiving element by controlling the drive current of the light-emitting element so that the drive current of the light-emitting element is small while providing the necessary amount of light for the light-receiving element (for example, Patent Document 1).

JP 2005-278758 A

However, as disclosed in Patent Document 1, the method of controlling the drive current of the light-emitting element has a limit to the amount of power consumption reduction, and there is room for improvement.

The object of this invention is to provide an optical biosensor device, a control method, and a program that can further reduce power consumption.

In order to achieve the above object, the present invention provides an optical biosensor device according to an aspect of the present invention,
A light emitting unit that irradiates light toward a living body;
a light receiving unit that detects light that is irradiated by the light emitting unit and transmitted through the living body;
a biometric information acquiring unit that acquires biometric information of the living body based on the intensity of the light detected by the light receiving unit;
a setting unit that sets a range or a lower limit of the light intensity detected by the light receiving unit according to the type of the biometric information, where the range or lower limit of the light intensity is capable of acquiring the biometric information;
a voltage control unit that controls a drive voltage of the light emitting unit based on the intensity of light detected by the light receiving unit and a range or a lower limit of the intensity of light at which the biometric information can be acquired, the range or lower limit being set according to the type of the biometric information;
Equipped with
When controlling the drive voltage of the light-emitting unit so as to change the intensity of the light, the voltage control unit performs control to change the drive voltage of the light-emitting unit in a stepwise manner.
It is characterized by:

By following this invention, power consumption can be further reduced.

1 is a block diagram showing an example of the configuration of an optical biosensor device according to an embodiment; FIG. 2 is a diagram showing an example of a schematic circuit diagram of an optical biosensor device according to an embodiment. 4 is a flowchart of a control process executed by the optical biosensor device according to the embodiment.

A preferred embodiment is described below with reference to the drawings.

Fig. 1 is a diagram showing an example of the functional configuration of an optical biosensor device 1 according to an embodiment. The optical biosensor device 1 according to this embodiment is a device that detects light L irradiated by a light emitting unit 140 (described later) that has passed through a living body 2 using a light receiving unit 150, measures the waveform of the change in blood vessel volume (volume pulse wave, hereinafter simply referred to as pulse wave) that occurs when blood is pumped from the heart of the living body 2 to the blood vessels based on the intensity of the light L, and acquires bioinformation of the living body 2 from the measurement results.

As biological information, for example, the pulse rate can be obtained from the period of fluctuation of the measured pulse wave, and the oxygen saturation concentration in arterial blood can be obtained from the pulsation when two lights, red and infrared, are irradiated. In addition, vascular age can be obtained as biological information from the accelerated pulse wave obtained by measuring the pulse wave with high accuracy.

As shown in FIG. 1, the optical biosensor device 1 functionally comprises a power supply unit 110, a power supply control unit 120, a current control unit 130, a light emitting unit 140, a light receiving unit 150, a voltage control unit 160, and a bioinformation acquisition unit 170.

The power supply unit 110 supplies power for the operation of the optical biosensor device 1. The power supply unit 110 is realized by, for example, a secondary battery such as a lithium ion battery.

The power supply control unit 120 converts the power supply voltage of the power supply unit 110, which supplies power to the light-emitting unit 140, into a drive voltage for driving the light-emitting unit 140 as instructed by the voltage control unit 160. The power supply control unit 120 is realized by a power supply IC (Integrated Circuit), for example, a boost DC/DC converter that boosts the voltage supplied from a secondary battery serving as the power supply unit 110, and converts the power supply voltage into a drive voltage represented by a control signal from the voltage control unit 160.

The current control unit 130 controls the drive current of the light emitting unit 140 based on the intensity of the light detected by the light receiving unit 150. The current control unit 130 is realized, for example, by a variable current limiting resistor connected in series with the light emitting unit 140, and controls the drive current by changing the resistance value of the current limiting resistor based on a control signal from the voltage control unit 160.

The light-emitting unit 140 irradiates light L toward the living body 2. The light-emitting unit 140 is realized by a light-emitting element such as an LED (Light Emitting Diode) or an LD (Laser Diode) capable of irradiating light L such as red visible light or infrared light. The light-emitting unit 140 irradiates light L with an intensity according to the drive current controlled by the current control unit 130.

The light receiving unit 150 detects the light L that is irradiated by the light emitting unit 140 and transmitted through the living body 2. The light receiving unit 150 then outputs a signal corresponding to the intensity of the detected light L to the voltage control unit 160 and the biological information acquisition unit 170. The light receiving unit 150 is realized by, for example, a light receiving element capable of receiving the light L irradiated by the light emitting unit 140.

The voltage control unit 160 controls the drive voltage of the light emitting unit 140 based on the intensity of the light L detected by the light receiving unit 150. More specifically, the voltage control unit 160 controls the drive voltage of the light emitting unit 140 based on the range of light intensity (measurement range) in which bioinformation can be acquired and the intensity of light detected by the light receiving unit 150. Specifically, the voltage control unit 160 further includes a determination unit 180 that determines the value of the drive current controlled by the current control unit 130 and the value of the drive voltage controlled by the voltage control unit 160, which can suppress the power consumption of the optical biosensor device 1. Then, the voltage control unit 160 controls the drive voltage of the light emitting unit 140 based on the determination result by the determination unit 180. Also, the current control unit 130 controls the drive current of the light emitting unit 140 based on the determination result by the determination unit 180. The voltage control unit 160 is realized, for example, by a judgment circuit that judges whether the intensity of the light L represented by the signal received from the light receiving unit 150 is within the measurement range, and a feedback circuit that outputs a control signal to the power supply control unit 120 to control the drive voltage of the light emitting unit 140 based on the judgment result, and the decision unit 180 is realized, for example, by the judgment circuit.

The biometric information acquisition unit 170 acquires biometric information of the living body 2 based on the intensity of the light L detected by the light receiving unit 150. The biometric information acquisition unit 170 is realized by, for example, a microcomputer equipped with a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), etc., and records the time transition of the light intensity represented by the signal received from the light receiving unit 150, and acquires biometric information such as pulse rate and vascular age based on the recorded data.

Next, an example of the circuit configuration of the optical biosensor device 1 according to this embodiment for realizing each function shown in FIG. 1 will be described. FIG. 2 is an example of a schematic circuit diagram of the optical biosensor device 1 according to this embodiment.

In the example shown in FIG. 2, the optical biosensor device 1 includes a battery 111 as the power supply unit 110, a power supply IC 121 as the power supply control unit 120, a current limiting resistor 131 as the current control unit 130, a light emitting element 141 as the light emitting unit 140, a light receiving element 151 as the light receiving unit 150, a determination circuit 161 and a feedback control circuit 162 as the voltage control unit 160, and a microcomputer 171 as the bioinformation acquisition unit 170.

The power supply IC 121 boosts the power supply voltage supplied from the battery 111 to the drive voltage Vd of the light-emitting element 141, which is represented by the control signal output from the feedback control circuit 162. As a result, the light-emitting element 141 emits light when a drive current I flows, which is determined by the drive voltage Vd, the forward voltage Vf of the light-emitting element 141, and the resistance value R of the current limiting resistor 131. The light irradiated by the light-emitting element 141 and transmitted through the living body 2 is detected by the light-receiving element 151. The light-receiving element 151 outputs a signal according to the intensity of the detected light to the judgment circuit 161 and the microcomputer 171.

The judgment circuit 161 is an example of the decision unit 180, and judges whether the light intensity represented by the signal from the light receiving element 151 is greater than the measurement lower limit. The measurement lower limit is the lower limit of the measurement range, i.e., the lower limit of the light intensity required to acquire bioinformation. The measurement range and measurement lower limit can be set according to the type of bioinformation to be acquired, such as pulse rate or vascular age. For example, when acquiring vascular age as bioinformation, which requires more accurate measurement of the pulse wave than pulse rate, the measurement lower limit may be set to a value higher than the measurement lower limit when acquiring pulse rate as bioinformation.

In this embodiment, when the light intensity is lower than the measurement lower limit, the judgment circuit 161 outputs a control signal to the current limiting resistor 131 to change the resistance value of the current limiting resistor 131 so that the drive current increases by a predetermined amount (for example, 5.0 [mA]). The judgment circuit 161 also outputs a signal to the feedback control circuit 162 to change the drive voltage so that the drive voltage increases by a predetermined amount (for example, 0.5 [V]). When the light intensity is greater than the measurement lower limit, the judgment circuit 161 outputs a signal to the current limiting resistor 131 to change the resistance value of the current limiting resistor 131 so that the drive current decreases by a predetermined amount (for example, 5.0 [mA]). The judgment circuit 161 also outputs a signal to the feedback control circuit 162 to change the drive voltage so that the drive voltage decreases by a predetermined amount (for example, 0.5 [V]). The feedback control circuit 162 outputs a control signal to the power supply IC 121 to boost the power supply voltage of the battery 111 to a drive voltage determined based on the signal from the judgment circuit 161.

The predetermined amount of change and sampling period of the drive current and drive voltage increased or decreased by the determination circuit 161 can be set according to the type of bioinformation to be acquired, such as pulse rate or vascular age. For example, when acquiring vascular age as bioinformation, which requires more accurate measurement of pulse waves than pulse rate, the predetermined amount of change and sampling period may be set to values smaller than the predetermined amount of change and sampling period when acquiring pulse rate as bioinformation.

Next, a method for suppressing power consumption in the optical biosensor device 1 according to this embodiment will be described. In this embodiment, the drive voltage and drive current of the light-emitting element 141 are controlled to suppress power consumption in the light-emitting element 141 and the power supply IC 121.

First, a description will be given of suppression of power consumption in the light-emitting element 141. For example, using a drive voltage Vd supplied by the power supply IC 121 shown in FIG. 2, a forward voltage Vf of the light-emitting element 141, and a resistance value R of the current limiting resistor 131, a drive current I flowing through the light-emitting element 141 is expressed by the following equation.
I=(Vd-Vf)/R
If the forward voltage Vf is a constant value, at least one of the driving voltage Vd and the resistance value R may be changed to change the driving current I. For example, when the driving voltage Vd=5.0 [V], the forward voltage Vf=2.0 [V], and the resistance value R=100 [Ω], the driving current I=(5.0-2.0)/100=30 [mA]. In this case, if the intensity of the light detected by the light receiving element 151 exceeds a predetermined range and the driving current I is reduced to reduce the power consumption of the light emitting element 141, if the resistance value R is changed to R=300 [Ω] while keeping the driving voltage Vd=5.0 [V], the driving current I can be reduced from 30 [mA] to 10 [mA] as I=(5.0-2.0)/300=10 [mA]. On the other hand, even if the driving voltage Vd is changed to Vd=3.0 [V] while the resistance value R is kept at 100 [Ω], the driving current I can be reduced from 30 [mA] to 10 [mA], such that I=(3.0-2.0)/100=10 [mA]. In other words, by changing the driving voltage Vd from 5.0 [V] to 3.0 [V] or changing the resistance value R from 100 [Ω] to 300 [Ω], the driving current I of the light-emitting element 141 can be reduced, and therefore the power consumption of the light-emitting element 141 can be suppressed.

Next, the suppression of power consumption in the power supply IC 121 will be described. As with a general power supply IC, the power supply IC 121 has a characteristic that the conversion efficiency deteriorates as the boost difference of the power supply voltage increases. For example, as shown in FIG. 2, if the voltage and current supplied to the power supply IC 121 from the battery 111 are Vin and Iin, and the voltage and current output from the power supply IC 121 are Vout and Iout, and Vin is a constant value (e.g., 2.4 [V]) and the same Iout is output, in the case of Vout = 3.0 [V] and the case of Vout = 5.0 [V], where the boost difference is large, a larger Iin is required than in the case of Vout = 3.0 [V], and therefore the conversion efficiency of the power supply voltage is poor. Therefore, by controlling the drive voltage Vd (Vout) so that the boost difference is as small as possible at the drive current I (Iout) that causes the intensity of the light detected by the light receiving element 151 to fall within a predetermined range, it is possible to optimize the conversion efficiency of the power supply voltage in the power supply IC 121 and suppress the power consumption in the power supply IC 121.

The optical biosensor device 1 according to this embodiment changes the drive voltage Vd and the drive current I by a predetermined amount at a predetermined sampling period so that the intensity of the light detected by the light receiving element 151 approaches the measurement lower limit. As a result, when the light intensity represented by the signal from the light receiving element 151 exceeds the measurement lower limit, the optical biosensor device 1 controls the drive voltage Vd and the drive current I to be an optimal combination of values that can suppress the power consumption of the optical biosensor device 1 as much as possible.

Next, the operation of the optical biosensor device 1 according to this embodiment will be described. FIG. 3 is a flow chart showing an example of a control process for controlling the drive voltage and drive current of the light-emitting element 141 executed by the optical biosensor device 1 in this embodiment. The optical biosensor device 1 starts the control process shown in FIG. 3 when, for example, the user turns on the power via an operation reception unit (not shown).

When the optical biosensor device 1 starts the control process, it sets the drive voltage of the light-emitting unit 140 output by the power supply control unit 120 to an initial value (e.g., 5.0 V) (step S101).

Then, the optical biosensor device 1 sets the drive current controlled by the current control unit 130 to an initial value (e.g., 30 mA) (step S102).

Then, the optical biosensor device 1 sets a measurement lower limit value and a sampling period (step S103). Here, the measurement lower limit value and the sampling period may be set by the user via an operation reception unit (not shown) according to the bioinformation to be measured, or a predetermined value may be set.

Then, the optical biosensor device 1 starts measuring bioinformation (step S104). When the optical biosensor device 1 starts measuring, it turns on the light-emitting unit 140 at the sampling period set in step S103.

Then, the optical biosensor device 1 detects light using the light receiving unit 150 at the sampling period set in step S103 (step S105). The light receiving unit 150 then outputs a signal representing the intensity of the detected light to the voltage control unit 160.

Then, the voltage control unit 160 of the optical biosensor device 1 determines whether the light intensity detected in step S105 is greater than the measurement lower limit (step S106). When the voltage control unit 160 determines that the light intensity is greater than the measurement lower limit (step S106; Yes), it outputs a control signal to the current control unit 130 to change the drive current to a value reduced by 5.0 [mA] from the current value, and outputs a control signal to the power supply control unit 120 to change the drive voltage to a value reduced by 0.5 [V] from the current value (step S107). The optical biosensor device 1 then returns to the processing of step S105.

On the other hand, when the voltage control unit 160 determines that the light intensity is not greater than the lower measurement limit (step S106; No), it outputs a control signal to the current control unit 130 to increase the drive current by 5.0 [mA], and outputs a control signal to the power supply control unit 120 to increase the drive voltage by 0.5 [V] (step S108). Then, the optical biosensor device 1 returns to the processing of step S105.

The optical biosensor device 1 ends the above process, for example, when the user turns off the power via an operation reception unit (not shown).

As described above, in the optical biosensor device 1 according to this embodiment, the light receiving unit 150 detects the light irradiated by the light emitting unit 140 to the living body 2 and transmitted through the living body 2, and the voltage control unit 160 controls the drive voltage of the light emitting unit 140 based on the intensity of the detected light. Therefore, when the intensity of the light detected by the light receiving unit 150 is greater than the intensity at which bioinformation can be acquired, the optical biosensor device 1 can reduce the power consumption of the optical biosensor device 1 by controlling the drive voltage of the light emitting unit 140 to be reduced.

In addition, in the optical biosensor device 1 according to this embodiment, the voltage control unit 160 controls the drive voltage of the light emitting unit 140 based on the measurement range of the light intensity at which bioinformation can be obtained and the light intensity detected by the light receiving unit 150. Therefore, the optical biosensor device 1 can reduce the power consumption of the optical biosensor device 1 by controlling the drive voltage of the light emitting unit 140 to be reduced while keeping the light intensity detected by the light receiving unit 150 within the range of intensity at which bioinformation can be obtained.

In addition, in the optical biosensor device 1 according to this embodiment, the voltage control unit 160 reduces the drive voltage of the light emitting unit 140 when the intensity of light detected by the light receiving unit 150 is greater than the measurement lower limit, and increases the drive voltage of the light emitting unit 140 when the intensity of light detected by the light receiving unit 150 is not greater than the measurement lower limit. Therefore, the optical biosensor device 1 can control the drive voltage of the light emitting unit 140 so that the intensity of light detected by the light receiving unit 150 is the minimum value required to acquire bioinformation, and as a result, the power consumption of the optical biosensor device 1 can be further reduced.

The optical biosensor device 1 according to this embodiment also includes a power supply control unit 120 that converts the power supply voltage of the power supply unit 110 that supplies power to the light emitting unit 140 into a drive voltage instructed by the voltage control unit 160, and the voltage control unit 160 instructs the power supply control unit 120 to convert the light intensity detected by the light receiving unit 150 into a drive voltage that is within the measurement range and minimizes the difference between the power supply voltage and the drive voltage. Therefore, the optical biosensor device 1 controls the drive voltage so that the conversion efficiency in the power supply control unit 120 is maximized while ensuring the light intensity that can acquire bioinformation, thereby reducing the power consumption of the power supply control unit 120.

The optical biosensor device 1 according to this embodiment also includes a current control unit 130 that controls the drive current of the light emitting unit 140 based on the intensity of light detected by the light receiving unit 150. Therefore, when the intensity of light detected by the light receiving unit 150 is greater than the intensity at which bioinformation can be acquired, the optical biosensor device 1 controls the drive current of the light emitting unit 140 to be reduced, thereby reducing the power consumption of the light emitting unit 140.

In addition, in the optical biosensor device 1 according to this embodiment, the measurement range is set according to the type of bioinformation. Therefore, even if the measurement range of the light intensity to be acquired differs depending on the type of bioinformation, such as pulse rate or vascular age, which requires more accurate pulse wave data than pulse rate, the optical biosensor device 1 can set a measurement range appropriate for that type of bioinformation, and therefore can acquire the bioinformation with greater accuracy.

In addition, in the optical biosensor device 1 according to this embodiment, the light emitter 140 irradiates light toward the living body 2 at a predetermined sampling period, the light receiver 150 detects the light that has passed through the living body 2 at the same sampling period, and the voltage controller 160 controls the drive voltage of the light emitter 140 based on the intensity of the light detected by the light receiver 150 at that sampling period. Therefore, the optical biosensor device 1 can perform feedback control of the drive voltage based on the intensity of the received light between the intermittent irradiation and reception by the light emitter 140 and the light receiver 150.

The present invention is not limited to the above embodiment, and various modifications are possible.

For example, in the above embodiment, an example was described in which both the drive voltage and the drive current are increased or decreased based on the intensity of the detected light in steps S107 and S108 of FIG. 3. However, the optical biosensor device 1 may control only the drive voltage to be increased or decreased based on the intensity of the detected light. In this case, even if the drive current does not change, the optical biosensor device 1 can reduce the power consumption of the power supply control unit 120 and the power consumption of the current limiting resistor 131 due to Joule heat by reducing the drive voltage.

In addition, for example, in the above-described embodiment, the optical biosensor device 1 controls the intensity of the light emitted by the light-emitting unit 140 by controlling the drive current of the light-emitting unit 140, but the light intensity may be controlled by PWM (Pulse Width Modulation) control.

In addition, for example, in the above embodiment, the optical biosensor device 1 has been described as controlling the drive voltage and drive current by feedback control so that the intensity of light detected by the light receiving unit 150 approaches the measurement lower limit value. However, the method in which the optical biosensor device 1 controls the drive voltage and drive current is not limited to this. For example, a correspondence table that associates the measurement lower limit value with the drive voltage and drive current at the measurement lower limit value may be stored in a ROM or the like, and the voltage control unit 160 may refer to the correspondence table and control to obtain the drive voltage and drive current corresponding to the measurement lower limit value. As the drive voltage and drive current that are associated with the measurement lower limit value in advance in this way, the average value of the drive voltage and drive current measured in the past may be used, or a value statistically obtained from the relationship between the measurement lower limit value measured in the past and the drive voltage and drive current may be used. In addition, the voltage control unit 160 may use a formula that represents the relationship between the measurement lower limit value and the drive voltage and drive current instead of the correspondence table to calculate the drive voltage and drive current corresponding to the measurement lower limit value, and control to obtain the calculated drive voltage and drive current. Also, for example, the drive current of the light emitting unit 140 may first be determined (this may be determined using the correspondence table as described above, or may be determined using a calculation formula) so that the intensity of the light detected by the light receiving unit 150 corresponds to the lower measurement limit value, and then the drive voltage may be controlled to minimize power consumption while maintaining that drive current.

In the above embodiment, for example, an example was described in which the voltage control unit 160 controls the drive voltage and drive current based on the detected light intensity using the judgment circuit 161 and the feedback control circuit 162. However, the functions of the voltage control unit 160 are not limited to those realized by dedicated circuits such as the judgment circuit 161 and the feedback control circuit 162. For example, some or all of the functions of the voltage control unit 160 may be realized by software control using a CPU. In more detail, for example, the voltage control unit 160 may refer to a correspondence table of light intensity, drive voltage, and drive current stored in advance in a ROM or the like to identify the values of the drive voltage and drive current corresponding to the detected light intensity, and control the drive voltage and drive current to be those values.

In addition, when some or all of the functions of the voltage control unit 160 and the functions of the biometric information acquisition unit 170 are realized by software control by a CPU, the program related to the software control may be recorded in a ROM consisting of a non-volatile memory such as a flash memory as a computer-readable medium. In addition, the computer-readable medium is not limited to these, and portable recording media such as a hard disk drive (HDD), a compact disc read only memory (CD-ROM) or a digital versatile disc (DVD) may also be applied. In addition, a carrier wave is also applied to the present invention as a medium for providing data of the program related to the software control via a communication line.

In addition, the specific details of the configuration, control procedures, display examples, etc. shown in the above embodiment may be modified as appropriate without departing from the spirit of the present invention.

Although several embodiments of the present invention have been described, the scope of the present invention is not limited to the above-described embodiments, but includes the scope of the invention described in the claims and their equivalents. The invention described in the claims first attached to this application is appended below. The appended number corresponds to the claim first attached to this application.

(Appendix 1)
A light emitting unit that irradiates light toward a living body;
a light receiving unit that detects light that is irradiated by the light emitting unit and transmitted through the living body;
a biometric information acquiring unit that acquires biometric information of the living body based on the intensity of the light detected by the light receiving unit;
a voltage control unit that controls a drive voltage of the light emitting unit based on the intensity of the light detected by the light receiving unit;
An optical biosensor device comprising:

(Appendix 2)
The voltage control unit controls a drive voltage of the light emitting unit based on a range of light intensity capable of acquiring the biological information and the light intensity detected by the light receiving unit.
2. The optical biosensor device according to claim 1 .

(Appendix 3)
the range is defined by a lower limit of the light intensity at which the biological information can be acquired,
the voltage control unit reduces a drive voltage of the light emitting unit when the intensity of the light detected by the light receiving unit is greater than the lower limit value, and increases a drive voltage of the light emitting unit when the intensity of the light detected by the light receiving unit is not greater than the lower limit value.
3. The optical biosensor device according to claim 2.

(Appendix 4)
a power supply control unit that converts a power supply voltage of a power supply unit that supplies power to the light-emitting unit into the drive voltage instructed by the voltage control unit;
the voltage control unit instructs the power supply control unit to convert the intensity of the light detected by the light receiving unit into the drive voltage such that the intensity of the light detected by the light receiving unit is within the range and a difference between the power supply voltage and the drive voltage is minimized.
4. The optical biosensor device according to claim 2 or 3.

(Appendix 5)
The range is set according to the type of the biometric information.
5. The optical biosensor device according to claim 2,

(Appendix 6)
a current control unit that controls a drive current of the light emitting unit based on the intensity of the light detected by the light receiving unit,
The voltage control unit further includes a determination unit that determines a value of the drive current controlled by the current control unit and a value of the drive voltage controlled by the voltage control unit, the determination unit being capable of suppressing power consumption of the optical biosensor device;
the voltage control unit controls a drive voltage of the light-emitting unit based on a result of the determination by the determination unit;
The current control unit controls a drive current of the light-emitting unit based on a result of the determination by the determination unit.
6. The optical biosensor device according to claim 1,

(Appendix 7)
The light emitting unit irradiates light toward the living body at a predetermined period,
The light receiving unit detects light that is irradiated by the light emitting unit and transmitted through the living body at the predetermined period,
the voltage control unit controls a drive voltage of the light emitting unit based on the intensity of the light detected by the light receiving unit at the predetermined period.
7. The optical biosensor device according to claim 1,

(Appendix 8)
A control method for an optical biosensor device including a light emitting unit that irradiates light toward a living body and a light receiving unit that detects light irradiated by the light emitting unit and transmitted through the living body,
a biometric information acquiring step of acquiring biometric information of the living body based on the intensity of the light detected by the light receiving unit;
a voltage control step of controlling a drive voltage of the light emitting unit based on the intensity of the light detected by the light receiving unit;
A control method comprising:

(Appendix 9)
A computer of an optical biosensor device including a light emitting unit that irradiates light toward a living body and a light receiving unit that detects the light irradiated by the light emitting unit and transmitted through the living body,
a biometric information acquiring means for acquiring biometric information of the living body based on the intensity of the light detected by the light receiving unit;
a voltage control means for controlling a drive voltage of the light emitting unit based on the intensity of the light detected by the light receiving unit;
A program characterized by causing the program to function as a

1...Optical biosensor device, 110...Power supply unit, 111...Battery, 120...Power supply control unit, 121...Power supply IC, 130...Current control unit, 131...Current limiting resistor, 140...Light emitting unit, 141...Light emitting element, 150...Light receiving unit, 151...Light receiving element, 160...Voltage control unit, 161...Determination circuit, 162...Feedback control circuit, 170...Bioinformation acquisition unit, 171...Microcomputer, 180...Decision unit

Claims (10)

A light emitting unit that irradiates light toward a living body;
a light receiving unit that detects light that is irradiated by the light emitting unit and transmitted through the living body;
a biometric information acquiring unit that acquires biometric information of the living body based on the intensity of the light detected by the light receiving unit;
a setting unit that sets a range or a lower limit of the light intensity detected by the light receiving unit according to a type of the biometric information, where the range or lower limit of the light intensity is capable of acquiring the biometric information;
a voltage control unit that controls a drive voltage of the light emitting unit based on the intensity of light detected by the light receiving unit and a range or a lower limit of the intensity of light at which the biometric information can be acquired, the range or lower limit being set according to the type of the biometric information;
Equipped with
When controlling the drive voltage of the light-emitting unit so as to change the intensity of the light, the voltage control unit performs control to change the drive voltage of the light-emitting unit in a stepwise manner.
1. An optical biosensor device comprising: a current control unit that controls a drive current of the light emitting unit based on the intensity of the light detected by the light receiving unit,
2. The optical biosensor device according to claim 1. When controlling the drive current of the light-emitting unit so as to change the intensity of the light, the current control unit performs control to change the drive current of the light-emitting unit in a stepwise manner.
3. The optical biosensor device according to claim 2. The voltage control unit changes a drive voltage of the light emitting unit so that the intensity of the light is changed stepwise,
the current control unit changes a drive current of the light emitting unit so that the intensity of the light is changed stepwise.
3. The optical biosensor device according to claim 2. The voltage control unit changes a drive voltage of the light emitting unit so that the intensity of the light is increased or decreased,
The current control unit changes a drive current of the light emitting unit so that the intensity of the light is increased or decreased.
3. The optical biosensor device according to claim 2. The light emitting unit irradiates light toward the living body at a predetermined period,
The light receiving unit detects light that is irradiated by the light emitting unit and transmitted through the living body at the predetermined period,
the voltage control unit controls a drive voltage of the light emitting unit based on the intensity of the light detected by the light receiving unit at the predetermined period.
6. The optical biosensor device according to claim 1, wherein the optical biosensor device is a semiconductor device. When the intensity of the light detected by the light receiving unit falls below a lower limit of the intensity of the light at which the biometric information can be acquired, the lower limit is set according to the type of the biometric information. ...
7. The optical biosensor device according to claim 1, wherein the optical biosensor device is a semiconductor device. The biological information includes pulse rate and vascular age.
8. The optical biosensor device according to claim 1, wherein the optical biosensor device is a semiconductor device. A control method for an optical biosensor device including a light emitting unit that irradiates light toward a living body and a light receiving unit that detects light irradiated by the light emitting unit and transmitted through the living body,
a biometric information acquiring step of acquiring biometric information of the living body based on the intensity of the light detected by the light receiving unit;
a setting step of setting a range or a lower limit of the light intensity detected by the light receiving unit according to the type of the biometric information, the range or a lower limit of the light intensity at which the biometric information can be obtained;
a voltage control step of controlling a drive voltage of the light emitting unit based on the intensity of light detected by the light receiving unit and a range or a lower limit of the intensity of light capable of acquiring the bioinformation, the range or lower limit being set according to the type of the bioinformation;
Equipped with
In the voltage control step, when the drive voltage of the light-emitting unit is controlled so as to change the intensity of the light, the drive voltage of the light-emitting unit is controlled to be changed in a stepwise manner.
A control method comprising: A computer of an optical biosensor device including a light emitting unit that irradiates light toward a living body and a light receiving unit that detects the light irradiated by the light emitting unit and transmitted through the living body,
a biometric information acquiring unit that acquires biometric information of the living body based on the intensity of the light detected by the light receiving unit;
a setting unit for setting a range or a lower limit of the light intensity detected by the light receiving unit according to the type of the biometric information, the range or lower limit of the light intensity at which the biometric information can be obtained;
a voltage control means for controlling a drive voltage of the light emitting unit based on the intensity of light detected by the light receiving unit and a range or a lower limit of the intensity of light capable of acquiring the biometric information, the range or lower limit being set according to the type of the biometric information;
Functioning as a
When controlling the drive voltage of the light-emitting unit so as to change the intensity of the light, the voltage control means performs control to change the drive voltage of the light-emitting unit in a stepwise manner.
A program characterized by:

Images