JP5192971B2 - Probe for optical biometric device and optical biometric device - Google Patents

Description

  The present invention relates to an optical biological measurement apparatus that emits inspection light to a living body and detects diffused light emitted from the living body as the light is emitted to measure internal information of the living body.

The following Patent Document 1 discloses such a technique. In Patent Literature 1, a light transmitting unit having an end surface that irradiates light to a living body, and a probe unit including a detector that receives transmitted diffused light from a living body at a position away from the light transmitting unit, and a plurality of wavelengths different from each other Signals connected to the optical transmission path consisting of a bundle of optical fibers that transmit light of the respective wavelengths emitted from the monochromatic light source, one end of which is coupled to the light transmission section of the probe section, and the detector of the probe section An optical probe device including a cable is disclosed.
Japanese Patent No. 3351151

  However, in the optical probe device disclosed in Patent Document 1, light is transmitted from a light source positioned outside the probe unit to a light transmitting unit positioned inside the probe unit by an optical transmission path formed of a bundle of optical fibers. For this reason, the transmission efficiency at the connection portion of the optical fiber is lowered, and it is necessary to increase the luminance of a plurality of monochromatic light sources built in the main body of the biological measurement apparatus. As a result, the apparatus could not be reduced in size. Further, since the signal from the detector of the probe unit is guided as an analog signal to the outside of the probe unit via the signal cable, noise is easily superimposed due to the antenna effect of the signal cable, and the signal is significantly deteriorated.

  The present invention has been made in view of the above problems, and aims to reduce the size of the apparatus and reduce noise.

  In order to solve the above problem, a probe for an optical biometric device according to the present invention is provided on a first wiring board, a first wiring board and a second wiring board that are arranged apart from each other, A light emitting unit that emits inspection light of a predetermined wavelength toward the living body, and a second wiring board, and is provided on the second wiring board to detect diffused light emitted from the living body with the emission of the inspection light by the light emitting unit, A light detection unit that outputs an electrical signal corresponding to the intensity of the diffused light, a flexible circuit board that connects the first wiring board and the second wiring board, and a flexible circuit board disposed along one surface. And a deformation holding portion having a conductive portion connected to a reference potential line and capable of holding a shape deformed by stress.

  The probe for an optical biometric device according to the present invention includes a light emitting unit that emits inspection light having a predetermined wavelength toward a living body. Therefore, it is not necessary to increase the luminance of the light source as in the conventional case where the light source is located outside the probe, and the apparatus can be miniaturized. In addition, since the probe for the optical biological measurement apparatus includes a deformation holding unit capable of holding a shape deformed by stress, it is possible to reduce the influence of artifacts due to the movement of the living body during use. Here, an artifact is a disturbance caused by a movement of a living body and the like, which causes an unnecessary signal component. Further, since the deformation holding part is disposed along one surface of the flexible circuit board and has a conductive part connected to the reference potential line, the wiring of the flexible circuit board picks up noise picked up by the antenna effect. A signal with a high signal / noise (S / N) ratio can be obtained.

  The optical biometric apparatus according to the present invention is provided on the first wiring board and the first wiring board and the second wiring board that are arranged apart from each other, and has a predetermined wavelength inspection toward the living body. A light emitting portion that emits light and an electrical signal that is provided on the second wiring board, detects diffused light emitted from the living body as the inspection light is emitted by the light emitting portion, and corresponds to the intensity of the diffused light Is connected to a reference potential line while being disposed along one surface of the flexible circuit board and a flexible circuit board for connecting the first wiring board and the second wiring board. And a deformable holding portion that can hold a shape deformed by stress, a module portion that drives the probe portion, and a module portion that is connected by a wireless data communication method. Based on the electrical signal output from the light detector A measuring unit for measuring the internal information of, characterized in that it comprises a.

  In the optical biometric apparatus according to the present invention, the probe unit includes a light emitting unit that emits inspection light having a predetermined wavelength toward the living body. Since the optical biological measuring apparatus according to the present invention employs such a configuration, it is not necessary to increase the luminance of the light source as in the case where the conventional light source is located outside the probe unit, and the apparatus is downsized. be able to. Further, in the optical biological measurement apparatus, since the probe part includes a deformation holding part capable of holding a shape deformed by stress, the influence of artifacts due to the movement of the living body when the apparatus is used can be reduced. In addition, since the deformation holding portion is disposed along one surface of the flexible circuit board and has a conductive portion connected to the reference potential line, the wiring of the flexible circuit board picks up noise picked up by the antenna effect. A signal with a high signal / noise (S / N) ratio can be obtained.

  In addition, the optical biological measurement apparatus is connected to the module unit that drives the probe unit and the module unit by a wireless data communication method, and measures internal information of the living body based on the electrical signal output from the light detection unit. And a measurement unit. Thus, since this optical biological measuring device employs a configuration in which the probe unit and the measuring unit are separated, the degree of freedom in using the probe unit can be improved and the device can be miniaturized.

  The probe unit further includes an AD conversion unit that performs analog-digital conversion on the electrical signal output from the light detection unit and outputs the converted digital signal. The digital signal output from the AD conversion unit is It is preferable that the data is transmitted to the module unit via wiring. Thereby, the information regarding the intensity | strength of the diffused light detected from the photon detection part is transmitted to a module part as a digital signal. Therefore, it is possible to suppress noise superposition and deterioration of the transmission signal when information on the intensity of the inspection light is transmitted as an analog signal, and it is possible to maintain the accuracy of the digital signal transmitted to the module unit. .

  According to the probe for optical biometric apparatus and the optical biometric apparatus according to the present invention, the apparatus can be reduced in size and noise can be reduced.

  The best mode for carrying out the present invention will be described below in detail with reference to the accompanying drawings. In the description of the drawings, equivalent elements are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a configuration diagram of a biological measurement apparatus 1 according to the present embodiment. FIG. 2 is a schematic configuration diagram of the biological measurement apparatus 1 shown in FIG. The optical biological measurement apparatus 1 according to the present embodiment includes a probe unit 3, a module unit 5, and a measurement unit 7.

  The probe unit 3 includes a flexible substrate 11, a first wiring substrate 13 and a second wiring substrate 15 which are arranged on one surface of the flexible substrate 11 and spaced from each other, and a deformation provided on the other surface of the flexible substrate 11. It has a holding part 17 and a connector 19 which is spaced apart from the first and second wiring boards 13 and 15 and is provided on the other surface of the flexible substrate 11 via the deformation holding part 17.

  The deformation holding part 17 is a plate-like thing (conductive part) made of Cu, for example, and is grounded to a ground potential (reference potential). The deformation holding part 17 has a bent part 17A and a flat part 17B connected to one end of the bent part 17A. The bending portion 17A can be curved in an arch shape by stress. The connector 19 is disposed on the end of the flat portion 17B, and the first and second wiring boards 13 and 15 are disposed on both inner ends of the bending portion 17A.

  On the first wiring board 13, an LED unit 21 that emits inspection light having a predetermined wavelength toward the living body B is provided so as to be physically and electrically connected to the first wiring board 13. Yes. On the second wiring board 15, the photodiode 23 and the AD converter (ADC) 27 are disposed so as to be physically and electrically connected to the second wiring board 15.

The LED unit 21 is a light emitting unit of the present embodiment, and includes LEDs 40 and 50 and an LED driver 21A. The LED 40 can emit inspection light S ₇₃₅ having a central wavelength of ₇₃₅ nm toward the living body B, and the LED 50 can emit inspection light S ₈₅₀ having a central wavelength of 850 nm. The LED driver 21 </ b> A is controlled by the module unit 5 to turn on or turn off the LED 40 and the LED 50 so that the inspection light S ₇₃₅ and the inspection light S ₈₅₀ are not emitted to the living body B at the same time. The inspection light S ₇₃₅ is light having a wavelength at which the absorption coefficient of oxygenated hemoglobin (HbO ₂ ) is smaller than the absorption coefficient of deoxygenated hemoglobin (Hb), while the inspection light S ₈₅₀ is oxygenated. Any light having a wavelength at which the extinction coefficient of hemoglobin is larger than the extinction coefficient of deoxygenated hemoglobin may be used, and the light is not limited to 735 nm and 850 nm.

The photodiode 23 is a light detection unit of the present embodiment, and has a spectral sensitivity characteristic that can sufficiently detect the inspection light S ₇₃₅ and the inspection light S ₈₅₀ . The photodiode 23 detects each diffused light emitted from the living body B as the inspection light S ₇₃₅ and the inspection light S ₈₅₀ are emitted to the living body B, and corresponds to the detected light intensity of each diffused light. An electrical signal SigA ₇₃₅ and an electrical signal SigA ₈₅₀ are generated. Further, the photodiode 23 outputs the electric signal SigA ₇₃₅ and the electric signal SigA ₈₅₀ to the amplifier circuit unit 25.

The amplifier circuit unit 25 amplifies the input electric signal SigA ₇₃₅ and electric signal SigA ₈₅₀ , respectively, and outputs the amplified electric signal SigB ₇₃₅ and electric signal SigB ₈₅₀ to the ADC 17. The ADC 17 converts the electrical signal SigB ₇₃₅ and the electrical signal SigB ₈₅₀ input from the amplifier circuit unit 25 from analog to digital, and transmits the converted digital signal AD ₇₃₅ and digital signal AD ₈₅₀ to the module unit 5.

  These components of the probe unit 3 are covered with a package 30 made of a rubber-like sheet so that the light emitting surfaces of the LEDs 40 and 50, the light receiving surface of the photodiode 23, and the connector 19 are exposed.

The module unit 5 is connected to the connector 19 of the probe unit 3 via a cable (electrical wiring) 71, and includes a wireless unit including a control unit 61, a data reception unit 63, a wireless transmission unit 65, and a wireless reception unit 67. Part 69. The control unit 61 controls the luminance of the inspection light emitted from the LED unit 21 in the probe unit 3 via the LED driver 21A and controls the gain of the photodiode 23 and the like. The data receiving unit 63 receives the digital signal AD ₇₃₅ and the digital signal AD ₈₅₀ from the ADC 27. The wireless unit 69 performs wireless data communication between the module unit 5 and the measuring unit 7. More specifically, the wireless unit 69 transmits the digital signal AD ₇₃₅ and the digital signal AD ₈₅₀ from the ADC 27 received by the data receiving unit 63 to the measuring unit 7 by the wireless transmission unit 65, and the wireless reception thereof. The unit 67 receives a command related to control of light emission and the like of the LEDs 40 and 50 from the calculation unit 7A of the measurement unit 7 (described later).

  The measurement unit 7 includes a calculation unit 7A and a display unit 7B, and is realized by a computer having a calculation unit such as a CPU (Central Processing Unit) and a storage unit such as a memory.

The calculation unit 7A receives the digital signal AD ₇₃₅ and the digital signal AD ₈₅₀ from the wireless transmission unit 65, and performs measurement calculation for quantifying the internal information of the living body B based on the digital signal AD ₇₃₅ and the digital signal AD _850. I do. The internal information measured by the calculation unit 7A is, for example, changes in blood oxygenated hemoglobin and deoxygenated hemoglobin in the living body B. The arithmetic unit 7A further has a function of controlling the light emission and the like of the LEDs 40 and 50, and these controls are performed by sending commands related to the respective controls of the module unit 5 via the wireless reception unit 67 of the module unit 5. This is realized by transmitting to the control unit 61.

  A display unit 7B is connected to the calculation unit 7A, and the calculation result in the calculation unit 7A, that is, the concentration change of oxygenated hemoglobin in blood and deoxygenated hemoglobin in the living body B can be displayed. .

(Measurement of hemoglobin concentration change)
Then, operation | movement of the optical biological measurement apparatus 1 which concerns on this embodiment is demonstrated. FIG. 3 is a timing chart showing (a) the irradiation time of the LED 40, (b) the irradiation time of the LED 50, and (c) the data acquisition time of the calculation unit 7A in one routine.

First, LED driver 21A LED 50 is lit during the emission time _{T ON} of the digital signal _{AD 850} in response to the emission of this inspection light _{S 850} is obtained by simultaneously calculating section 7A. Then, LED driver 21A by lit during the emission time _{T ON} of the LED 40, a digital signal _{AD 735} in response to the emission of this inspection light _{S 735} is obtained by simultaneously calculating section 7A. Next, in a state where neither of the LEDs 40 and 50 is lit, the arithmetic unit 7A acquires the digital signal AD _Dark corresponding to this non-lit state. Accordingly, the inspection light S ₇₃₅ and the inspection light S ₈₅₀ having different center wavelengths are emitted to the living body B at different timings.

In the optical biological measurement apparatus 1 according to the present embodiment, this routine is repeated as one routine. Next, a method for measuring changes in oxygenated hemoglobin and deoxygenated hemoglobin concentrations in the living body B performed by the calculation unit 7A will be described based on the data thus obtained. The digital signal AD ₇₃₅ and the digital signal AD ₈₅₀ when the time t has elapsed from the time when the data acquisition is started by the arithmetic unit 7A (t = 0) are respectively AD ₇₃₅ (t) and AD ₈₅₀ (t), and the LED light source Assuming that the digital conversion value by the ADC 17 when the signal is not emitted is a digital signal AD _Dark (t), the change in light attenuation ΔOD ₇₃₅ (t) at a wavelength of ₇₃₅ nm and the change in light attenuation ΔOD ₈₅₀ (t) at ₈₅₀ nm are respectively expressed by the following equations: It is calculated | required by (1) and Formula (2). Here, the light attenuation change refers to a change in the intensity of detection light caused by a change in hemoglobin concentration.

By applying the Modified Beer-Lambert rule to each of the formulas (1) and (2), the following formulas showing the oxygenated hemoglobin concentration change ΔHbO ₂ (t) and the deoxygenated hemoglobin concentration change ΔHb (t) ( 3) and equation (4) are derived.

Here, ε _i ^j (i is HbO ₂ or Hb) is an absorption coefficient shown in Table 1 below.

Thus, the attenuation change ΔOD ₇₃₅ (t) at the wavelength ₇₃₅ nm and the attenuation change ΔOD ₈₅₀ (t) at the wavelength 850 nm obtained from the digital signals AD ₇₃₅ (t), AD ₈₅₀ (t), and AD _Dark (t) by the ADC 17. t) and absorption coefficient ε _i ^j (i is HbO ₂ or Hb) are substituted into equations (3) and (4) to change oxygenated hemoglobin concentration change ΔHbO ₂ (t) and deoxygenated hemoglobin concentration change. ΔHb (t) is measured, and the result is displayed on the display unit 7B.

In the optical biometric apparatus 1 according to the present embodiment, the probe unit 3 includes LEDs 40 and 50 that emit test light S ₇₃₅ and test light S ₈₅₀ having different center wavelengths toward the living body B, respectively. Since the optical biological measuring apparatus 1 employs such a configuration, it is not necessary to increase the luminance of the light source as in the conventional case where the light source is located outside the probe unit, and the apparatus can be miniaturized. Moreover, in this optical biological measuring device 1, the probe part 3 is provided on the flexible substrate 11 and includes a plate-like deformation holding part 17 made of Cu capable of holding a shape deformed by stress. Therefore, it is possible to keep the probe unit 3 in close contact with the living body B as compared with the case where the probe unit 3 is in a soft state, and it is possible to reduce the influence of artifacts caused by the movement of the living body B and the like when the optical biological measuring apparatus 1 is used. Further, since the deformation holding unit 17 is electrically grounded, noise picked up by the wiring of the flexible substrate 11 due to the antenna effect can be removed, and a signal with a high S / N ratio can be acquired.

  In addition, since the probe unit 3 and the measurement unit 7 are separated and connected by a wireless data communication method, the degree of freedom in using the probe unit 3 can be improved, and the apparatus can be downsized and portable. Can be achieved.

The probe unit 3 includes an AD conversion unit 27 that performs analog-to-digital conversion on the electrical signals SigA ₇₃₅ and SigA ₈₅₀ output from the photodiode 23 and outputs the converted digital signals AD ₇₃₅ and AD _850. The digital signals AD ₇₃₅ and AD ₈₅₀ output from the unit 27 are transmitted to the module unit 5 via the cable 71. Therefore, it is possible to suppress noise superposition and deterioration of the transmission signal due to the antenna effect of the cable 71 in the case where information regarding the intensity of the inspection light is transmitted as an analog signal. As a result, the accuracy of the digital signals AD ₇₃₅ and AD ₈₅₀ transmitted to the module unit 5 can be maintained.

  The probe for an optical biometric device and the optical biometric device according to the present invention are not limited to the above-described embodiments, and various other modifications are possible. For example, in the present embodiment, the LEDs 40 and 50 are used as the light emitting part, but the present invention is not limited to this, and other light emitting elements may be used as long as they can be stored in the probe part 3.

  Further, in the present embodiment, the deformation holding portion 17 is provided on the flexible substrate 11, but may be provided inside the flexible substrate 11. Further, the deformation holding portion 17 is a plate-shaped member made of Cu, but may be a mesh-shaped or linear one. Further, in the present embodiment, the deformation holding portion 17 as a whole functions as a conductive portion that is in contact with the flexible substrate 11 and is electrically grounded, but a part thereof functions as a conductive portion. May be.

  Moreover, although the deformation | transformation holding | maintenance part 17 is comprised from Cu, you may be comprised by metal materials and electroconductive materials other than Cu. Moreover, although the optical biological measurement apparatus 1 is used for measuring the concentration change of blood oxygenated hemoglobin and deoxygenated hemoglobin, the present invention is not limited to this, and other internal information may be measured. Moreover, although the LED part 21 is comprised by two LED40 and 50, it is not restricted to this, You may be comprised by 1 or 3 or more LED.

It is a block diagram of the optical biological measurement apparatus 1 which concerns on this embodiment. It is a figure which shows the schematic block diagram of the optical biological measurement apparatus 1 shown in FIG. It is a timing chart for demonstrating operation | movement of the optical biological measurement apparatus 1 which concerns on this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Optical biological measuring device, 3 ... Probe part, 5 ... Module part, 7 ... Measurement part, 11 ... Flexible board, 13 ... 1st wiring board, 15 ... 2nd wiring board, 17 ... Deformation holding part, 21 ... LED Part, 23... Photodiode.

Claims (3)

A first wiring board and a second wiring board that are spaced apart from each other;
A light emitting unit that is provided on the first wiring board and emits inspection light having a predetermined wavelength toward a living body;
Light that is provided on the second wiring board, detects diffused light emitted from the living body as the inspection light is emitted by the light emitting unit, and outputs an electrical signal corresponding to the intensity of the diffused light A detection unit;
A flexible circuit board connecting the first wiring board and the second wiring board;
A deformable holding portion disposed along one surface of the flexible circuit board and having a conductive portion connected to a reference potential line, and capable of holding a shape deformed by stress;
A probe for an optical living body measuring apparatus. A first wiring board and a second wiring board that are spaced apart from each other;
A light emitting unit that is provided on the first wiring board and emits inspection light having a predetermined wavelength toward a living body;
Light that is provided on the second wiring board, detects diffused light emitted from the living body as the inspection light is emitted by the light emitting unit, and outputs an electrical signal corresponding to the intensity of the diffused light A detection unit;
A flexible circuit board connecting the first wiring board and the second wiring board;
A deformable holding portion disposed along one surface of the flexible circuit board and having a conductive portion connected to a reference potential line, and capable of holding a shape deformed by stress;
A probe unit including:
A module unit for driving the probe unit;
A measurement unit that is connected to the module unit by a wireless data communication method, and measures internal information of the living body based on the electrical signal output from the light detection unit;
An optical biological measurement apparatus comprising: The probe unit further includes an AD conversion unit that performs analog-digital conversion on the electrical signal output from the light detection unit and outputs a converted digital signal,
The optical biological measurement apparatus according to claim 2, wherein the digital signal output from the AD conversion unit is transmitted to the module unit via an electrical wiring.

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