JPWO2011007409A1 - Holder and optical biometric apparatus using the same - Google Patents

Abstract

A holder 11 to be mounted on the surface of a subject's head. The holder 11 has a hexagon around the pentagon and alternately forms a pentagon and a hexagon around the hexagon. In addition, a through hole into which the light transmitting probe 12 or the light receiving probe 13 is inserted is provided at a position corresponding to a pentagonal vertex and a center of gravity and a hexagonal vertex and a center of gravity. Is inserted, and the light receiving probe 13 is inserted at the position that becomes the apex, or the light receiving probe 13 is inserted at the position that becomes the center of gravity, and the light transmitting probe is inserted at the position that becomes the apex. 12 is inserted.

Description

  The present invention relates to a holder for non-invasively measuring brain activity and an optical biometric apparatus using the holder.

In recent years, in order to observe the activity state of the brain, an optical brain functional imaging apparatus (optical biometric apparatus) that performs simple noninvasive measurement using light has been developed. In such an optical brain functional imaging apparatus, near-infrared light of two different wavelengths λ ₁ and λ ₂ (for example, 780 nm and 830 nm) is transmitted to the brain by a light transmission probe arranged on the head surface of the subject. , And the intensity (received light amount information) A (λ ₁ ) and A (λ ₂ ) of near-infrared light of each wavelength emitted from the brain is detected by a light receiving probe arranged on the head surface. .
Then, from the received light quantity information A (λ ₁ ) and A (λ ₂ ) thus obtained, the concentration / optical path length product [oxyHb] of oxyhemoglobin in the cerebral blood flow and the concentration / optical path length of deoxyhemoglobin In order to obtain the product [deoxyHb], for example, the simultaneous equations shown in the relational expressions (1) and (2) are created using the Modified Beer Lambert rule, and the simultaneous equations are solved (for example, Non-Patent Document 1). reference). Furthermore, the concentration / optical path length product of total hemoglobin ([oxyHb] + [deoxyHb]) is calculated from the concentration / optical path length product [oxyHb] of oxyhemoglobin and the deoxyhemoglobin concentration / optical path length product [deoxyHb]. Yes.
A (λ ₁ ) = E _O (λ ₁ ) × [oxyHb] + E _d (λ ₁ ) × [deoxyHb] (1)
A (λ ₂ ) = E _O (λ ₂ ) × [oxyHb] + E _d (λ ₂ ) × [deoxyHb] (2)
E _O (λm) is an absorbance coefficient of oxyhemoglobin in light having a wavelength λm, and E _d (λm) is an absorbance coefficient of deoxyhemoglobin in light having a wavelength λm.

Here, the relationship between the distance (channel) between the light transmitting probe and the light receiving probe and the measurement site will be described. FIG. 6A is a cross-sectional view showing a relationship between a pair of light transmitting probe and light receiving probe and a measurement site, and FIG. 6B is a plan view of FIG. 6A.
The light transmitting probe 12 is pressed against the light transmitting point T on the subject's head surface, and the light receiving probe 13 is pressed against the light receiving point R on the subject's head surface. Then, light is emitted from the light transmitting probe 12 and light emitted from the head surface is incident on the light receiving probe 13. At this time, among the light irradiated from the light transmission point T on the head surface, the light that has passed through the banana shape (measurement region) reaches the light receiving point R on the head surface. As a result, the light transmitting point T and the light receiving point R from the middle point M of the line L connecting the light transmitting point T and the light receiving point R at the shortest distance along the head surface of the subject in the measurement region. Received light quantity information A (λ ₁ ), A (λ for the measurement site S of the subject having a depth L / 2 that is half the distance of the line connecting the head and the head along the subject's head surface. ₂ ) is obtained.

In the optical brain functional imaging system, oxyhemoglobin concentration / optical path length product [oxyHb], deoxyhemoglobin concentration / optical path length product [deoxyHb] and total hemoglobin concentration / optical path length product (multiple measurement sites in the brain) In order to measure [oxyHb] + [deoxyHb]), for example, a near-infrared spectrometer is used.
In a near-infrared spectrometer, a holder is used to bring a light-transmitting probe and a light-receiving probe into contact with the subject's head surface in a predetermined arrangement. The holder is provided with a plurality of through-holes, and by inserting the light-transmitting probe and the light-receiving probe into the through-holes, the probe interval between the light-transmitting probe and the light-receiving probe is constant, and a specific distance from the head surface The received light amount information that is the depth is obtained. Note that the probe interval is called a channel, and a channel with a channel of 30 mm is generally used. When the channel is 30 mm, received light amount information with a depth of 15 mm to 20 mm from the midpoint of the channel is obtained. It is believed that. That is, the position at a depth of 15 mm to 20 mm from the head surface substantially corresponds to the brain surface region, and the received light amount information A (λ ₁ ) and A (λ ₂ ) related to the brain activity is obtained.

Here, FIG. 7 is a plan view showing a conventional arrangement of a plurality of light transmitting probes and a plurality of light receiving probes. Fifteen light transmitting probes (black circles) 12 and fifteen light receiving probes (white circles) 13 are arranged in a square lattice pattern so as to alternate in the row direction and the column direction. Then, light is emitted from the light-transmitting probe 12 and the light-receiving probe 13 adjacent to the light-transmitting probe 12 that has emitted the light is detected to detect the light emitted from the head surface, thereby receiving light reception amount information A (λ ₁ ). , A (λ ₂ ). Accordingly, when viewed in plan as shown in FIG. 7, the measurement site (x mark) S is the midpoint between the light transmitting probe 12 and the light receiving probe 13 that receives light from the light transmitting probe 12, for a total of 49 pieces. The received light amount information A (λ ₁ ) and A (λ ₂ ) is collected.

By the way, the curvature of the head surface varies depending on gender differences, age differences, and individual differences. Therefore, the light transmitting probe 12 and the light receiving probe 13 can be easily handled even if there is a difference in curvature of the head surface. The holding parts to be held are arranged in a square lattice pattern on the head surface, and the holding parts are connected by a connecting part exhibiting elasticity within a predetermined range, and further, the rotational variability of the connecting part is set within a predetermined angle. The holder which has is proposed (for example, refer patent document 1).
In addition, a holder made of a holder part that connects the holding portion with a connecting portion that does not exhibit elasticity has also been proposed (see, for example, Patent Document 2). 4 and 5 are diagrams for explaining the holder part. FIG. 4 is an exploded perspective view showing the light transmission probe 12, the nut part 32, the two connection parts 31, and the socket part 33. FIG. 5 is a diagram illustrating the light transmission probe 12, the nut part 32, the two connection parts 31, and the socket part 33 after being assembled.
The holder includes 15 light transmitting probes 12, 15 light receiving probes 13, 30 socket parts 33 for fixing the light transmitting probes 12 and the light receiving probes 13, 49 connection parts 31, and 30 A nut part 32.
The connection part 31 is a plate-shaped body having a single letter shape. And the connection component 31 has the annular-shaped insertion part 31a at both ends, and the connection part 31b which connects the insertion part 31a of both ends with the channel length X. FIG. In the center of each insertion portion 31a, a circular through-hole for inserting the socket component 33 is opened. The connecting portion 31b has a width of 10 mm and a thickness of 0.1 mm, and is formed such that the distance between the center of the through hole and the center of the through hole is a channel length of 30 mm. Only flexible in the direction. That is, the insertion portions 31a at both ends are always held at the channel length X. The material constituting the connection component 31 is not particularly limited, and examples thereof include polypropylene, polyvinyl chloride, and polyacetal.

  7 using the 15 light transmitting probes 12, 15 light receiving probes 13, 30 socket parts 33, 49 connecting parts 31 and 30 nut parts 32. Make it. According to such a holder, as shown in FIG. 5 (a), one connecting component 31 and the other connecting component 31 are socket components as viewed from above in order to be attached so as to be in close contact with the head surface. As shown in FIG. 5 (b), the connecting portion 31b of the connection component 31 is flexible and has a curvature that matches the head surface. It can be deformed to be a surface.

JP 2002-143169 A JP 2009-77841 A

Factors affecting the accuracy of near-infrared spectroscopy concentration calculations for focal changes in oxygenation parameters, NeuroImage 18, 865-879, 2003

However, when a holder using a connecting portion exhibiting elasticity as described above is used, the light-transmitting probe 12 and the light-receiving probe 13 are caused by expansion and contraction of the connecting portion when closely contacting the head surface of various curvatures. As a result, the received light amount information A (λ ₁ ) and A (λ ₂ ) at the depth corresponding to the brain surface region may not be obtained.
In addition, when a holder using a connecting portion that does not exhibit stretchability is used, the distance (channel) between the light transmitting probe 12 and the light receiving probe 13 does not change, but it is closely attached to the head surface with various curvatures. At this time, the square lattice is deformed into a rhombus, and as a result, the intervals between the measurement sites (x marks) S may be uneven.

  In order to solve the above problems, the present inventors have examined the arrangement of the plurality of light transmitting probes 12 and the plurality of light receiving probes 13. As a result, a plurality of light transmitting probes 12 and a plurality of light receiving probes 13 as shown in FIG. 7 are arranged in a square lattice pattern so as to alternate in the row direction and the column direction. It turned out that it was impossible to make it adhere to. Therefore, a hexagon is formed around the pentagon, and pentagons and hexagons are alternately formed around the hexagon. Alternatively, it has been found that the light receiving probe 13 is arranged.

  That is, the holder of the present invention is a holder that holds a plurality of light-transmitting probes that irradiate light from the tip and a plurality of light-receiving probes that receive light from the tip and is mounted on the surface of the subject's head. In the holder, a hexagon is formed around the pentagon, and a pentagon and a hexagon are alternately formed around the hexagon, and the vertex of the pentagon and the center of gravity and the vertex of the hexagon are formed. And a through hole into which the light transmitting probe or the light receiving probe is inserted is provided at the position to be the center of gravity, and at the position to be the center of gravity, the light transmitting probe is inserted and at the position to be the top. The light receiving probe is inserted, or the light receiving probe is inserted at the center of gravity, and the light transmitting probe is inserted at the top. .

  According to the holder of the present invention, the distance between the light-transmitting probe and the light-receiving probe is not changed, and the distance between the measurement parts does not become non-uniform, so that the holder is in close contact with a surface having various curvatures. Can do.

(Means and effects for solving other problems)
The holder of the present invention comprises a plurality of holder parts having a single letter shape. The holder part includes a socket part for holding one light transmitting probe or one light receiving probe at each end, and the socket part at a fixed interval. And the holder part is rotatable with respect to the other holder part about the socket part as a rotation axis within the contact surface of the head surface. You may make it have flexibility by a connection part in a line direction.

  The optical biometric apparatus of the present invention includes a holder as described above, a plurality of light transmitting probes that irradiate light from the tip, a plurality of light receiving probes that receive light from the tip, and the light transmitting probe and the light receiving probe. And a controller for controlling light transmission / reception.

It is a block diagram which shows schematic structure of the optical biometric apparatus which is one Embodiment of this invention. It is a perspective view which shows the net-shaped body with which the mannequin head was mounted | worn. It is a perspective view which shows schematic structure of a holder. It is a disassembled perspective view which shows a light transmission probe, a nut component, two connection components, and a socket component. It is a figure which shows the light transmission probe, nut component, two connection components, and socket component after an assembly. It is a figure which shows the relationship between a pair of light transmission probe and light reception probe, and a measurement site | part. It is a top view which shows the conventional arrangement | positioning of a some light transmission probe and a some light reception probe.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments described below, and it goes without saying that various aspects are included without departing from the spirit of the present invention.

FIG. 1 is a block diagram showing a schematic configuration of an optical biometric apparatus according to an embodiment of the present invention. FIG. 2 is a perspective view showing a net-like body mounted on the mannequin head, and FIG. 3 is a perspective view showing a schematic configuration of the holder. In FIG. 1 and FIG. 3, the light transmitting probe is indicated by a black circle, and the light receiving probe is indicated by a white circle. Moreover, the same code | symbol is attached | subjected about the thing similar to the conventional holder mentioned above.
The optical biometric apparatus 1 includes a holder 11 for mounting on the head surface of a subject, a light emitting unit 2 connected by a light transmission probe 12 and a light guide (not shown), a light receiving probe 13 and a light guide. It is comprised by the photon detection part 3 connected by the optical path (not shown), and the control part (computer) 20 which performs control of the optical biometric apparatus 1 whole.

First, components constituting the holder 11 will be described. FIG. 4 is an exploded perspective view showing the light transmission probe 12, the nut part 32, the two connection parts 31, and the socket part 33.
The holder 11 includes 11 light transmission probes 12, 20 light reception probes 13, 31 socket parts 33 for fixing the light transmission probes 12 and the light reception probes 13, 50 connection parts 31 and 31 pieces. The nut part 32 is provided.

The light transmission probe 12 has an elongated cylindrical shape whose upper end portion is slightly larger to be fixed to the socket component 33. And the upper end part of the light transmission probe 12 is connected with the light emission part 2 via light guides, such as an optical fiber, and irradiates light from a lower end part.
The light receiving probe 13 is also in the shape of an elongated cylinder having a slightly larger upper end similar to the light transmitting probe 12. The upper end of the light receiving probe 13 is connected to the light detection unit 3 via a light guide such as an optical fiber, and receives light at the lower end.

The socket part 33 has a cylindrical main body 33a, an annular jaw 33b, and an annular bottom (contact mechanism) 33c, and the light transmitting probe 12 and the light receiving probe 13 are inserted therein. In addition, a screw (fixing mechanism) to which the nut part 32 is screwed is formed on the outer peripheral surface of the main body portion 33a.
In addition, although it does not specifically limit as a material which comprises the main-body part and jaw part of the said socket component, For example, a polypropylene, a polyvinyl chloride, a polyacetal etc. are mentioned.
Moreover, as a material which comprises the bottom part of the said socket component, if it can closely_contact | adhere to the head surface, it will not specifically limit, For example, sponge etc. are mentioned.
Accordingly, the socket component 33 and the light transmission probe 12 are fixed by inserting the light transmission probe 12 inside the socket component 33. At this time, it fixes so that the bottom face of the bottom part 33c and the lower end surface of the light transmission probe 12 may become the same plane. Therefore, since the bottom 33c is brought into contact with the head surface together with the light transmitting probe 12, the bottom 33c is brought into close contact with the head surface. Furthermore, since the bottom 33c plays a role of pressing the hair or the like, the light transmitting probe 12 can be brought into contact with the head surface by simply inserting the light transmitting probe 12 inside the socket part 33.
Similar to the light transmission probe 12, the light receiving probe 13 is inserted inside the socket component 33, thereby fixing the socket component 33 and the light receiving probe 13.

The nut part 32 has an annular shape having a circular through hole, and a female screw that is screwed into the main body part 33 a of the socket part 33 is formed on the inner peripheral surface thereof. Note that the size of the through hole is larger than the size of the main body portion 33 a of the socket component 33 and smaller than the jaw portion 33 b of the socket component 33 when viewed from above.
The material constituting the nut part is not particularly limited, and examples thereof include polypropylene, polyvinyl chloride, and polyacetal as well as the material constituting the body part and the jaw part of the socket part.
Thus, the insertion portion 31a of the connection component 31 is inserted between the jaw portion 33b of the socket component 33 and the nut component 32 by inserting the main body portion 33a of the socket component 33 into the nut component 32 using a screw mechanism. It can be pinched and fixed. At this time, when fixing one connection component 31, the insertion portion 31 a of one connection component 31 is sandwiched between the jaw portion 33 b of the socket component 33 and the nut component 32. On the other hand, when fixing the five connection parts 31, the insertion parts 31 a of the five connection parts 31 are sandwiched between the jaw parts 33 b of the socket part 33 and the nut parts 32. In other words, an arbitrary number of connection parts 31 can be fixed.

Next, an assembling method for assembling 11 light transmitting probes 12, 20 light receiving probes 13, 31 socket parts 33, 50 connecting parts 31 and 31 nut parts 32 in the holder 11 will be described. (See FIG. 3).
First, a pentagon is formed. The through holes of the insertion parts 31a of the five connection parts 31 are overlapped, and the main body part 33a of the socket part 33 is inserted into the five through holes from below, and further screwed into the through holes of the nut part 32 from below. Insert using mechanism. At this time, one connecting component 31 and the other connecting component 31 are viewed from above by tightening with a screw mechanism so that the five connecting components 31 are sandwiched between the jaw 33b of the socket component 33 and the nut component 32. The socket part 33 can be fixed so as to form a desired angle with the socket part 33 as an axis, but one connection part 31 and the other connection part 31 form 72 ° with the socket part 33 as an axis when viewed from above. Fix it. That is, a regular pentagon is formed by connecting the five insertion portions 31a into which the socket component 33 is not inserted. Further, five insertion portions 31a into which the socket parts 33 are inserted are arranged at the center of gravity of the regular pentagon.

  Next, a hexagon is formed. The through holes of the insertion parts 31a of the six connection parts 31 are overlapped, the main body part 33a of the socket part 33 is inserted into the six through holes from below, and further the screws from below into the through holes of the nut part 32 Insert using mechanism. At this time, one connecting component 31 and the other connecting component 31 are viewed from above by tightening with a screw mechanism so that the six connecting components 31 are sandwiched between the jaw 33b of the socket component 33 and the nut component 32. The socket part 33 can be fixed so as to form a desired angle with the socket part 33 as an axis, but one connection part 31 and the other connection part 31 form 60 ° with the socket part 33 as an axis when viewed from above. Fix it. That is, a regular hexagon is formed by connecting the six insertion portions 31a into which the socket component 33 is not inserted. Further, six insertion portions 31a into which the socket parts 33 are inserted are arranged at the center of gravity of the regular hexagon. And five such hexagons are produced.

  Next, a partial pentagon is formed. The through holes of the insertion parts 31a of the three connection parts 31 are overlapped, and the main body part 33a of the socket part 33 is inserted into the three through holes from below, and further screwed into the through holes of the nut part 32 from below. Insert using mechanism. At this time, one connecting component 31 and the other connecting component 31 are viewed from above by tightening with a screw mechanism so that the three connecting components 31 are sandwiched between the jaw 33b of the socket component 33 and the nut component 32. The socket part 33 can be fixed so as to form a desired angle with the socket part 33 as an axis, but one connection part 31 and the other connection part 31 form 72 ° with the socket part 33 as an axis when viewed from above. Fix it. That is, when three insertion portions 31a into which the socket part 33 is not inserted are connected, a part of a regular pentagon is formed. In addition, at the center of gravity of the regular pentagon, three insertion portions 31a into which the socket parts 33 are inserted are arranged. And five such regular pentagons of a part are produced.

Next, five hexagons are formed around one pentagon. The two insertion portions 31a arranged at the vertex of one side of the pentagon and the two insertion portions 31a arranged at the vertex of one side of the hexagon overlap each other, and the vertex of the other side of the hexagon The jaw part 33b and the nut part 32 of the one socket part 33 are arranged so that the two inserted parts 31a and the two inserted parts 31a arranged at the apex of one side of the other hexagon overlap each other. The insertion parts 31 a of the three connection parts 31 are sandwiched between the insertion parts 31 a and the insertion parts 31 a of the three connection parts 31 are sandwiched between the jaw parts 33 b of the other socket parts 33 and the nut parts 32. In this manner, five hexagons are formed around one pentagon.
Next, a pentagon, a hexagon, a partial pentagon, a partial pentagon, and a hexagon are formed in this order around one hexagon. The two insertion portions 31a arranged at the vertices of one side of a part of the pentagon and the two insertion portions 31a arranged at the vertices of one side of the hexagon overlap each other, and the other side of the part of the pentagon The jaw portion 33b and the nut of one socket part 33 are arranged so that the two insertion portions 31a arranged at the apex of the socket and the two insertion portions 31a arranged at the apex of one side of the other hexagon overlap each other. The insertion parts 31 a of the two connection parts 31 are sandwiched between the parts 32 and the insertion parts 31 a of the two connection parts 31 are sandwiched between the jaw parts 33 b of the other socket parts 33 and the nut parts 32.
As a result, the net-like body shown in FIG. 2 is produced. FIG. 2B shows the net-like body shown in FIG. 2A viewed from another angle.

Then, the produced net-shaped body is mounted on the surface of the head of the subject. At this time, since the head surface of the subject has a curved surface shape, one connecting component 31 and another connecting component 31 are attached as shown in FIG. Is fixed so as to form a desired angle with the socket part 33 as an axis when viewed from above, and the connecting part 31b of the connection part 31 is flexible as shown in FIG. The surface is deformed to have a curvature that matches the surface.
At this time, if the angle formed by the angle between one connection component 31 and the other connection component 31 is fixed in a deformed state, the curvature is maintained.
Finally, the light transmitting probe 12 is inserted inside the socket part 33 arranged at the position where the center of gravity of the pentagon and the center of the hexagon are located, and the socket is arranged at the position where the vertex of the pentagon and the hexagon are located. The holder 11 is manufactured by inserting the light receiving probe 13 inside the component 33.

Next, configurations other than the above-described holder 11 will be described.
The light-emitting unit 2 is a light source that transmits light to one light-transmitting probe 12 selected from among the 11 light-transmitting probes 12 according to a drive signal input from the computer 20, for example, an LED (light-emitting diode). ) And LD (laser diode).
Near-infrared light (for example, 780 nm and 830 nm) is used as the light.
The light detection unit 3 is a detector that outputs 20 received light signals to the computer 20 by individually detecting near-infrared light received by the 20 light receiving probes 13, for example, a photodiode or a phototransistor. A light receiving element such as a photomultiplier tube.

The computer 20 includes a CPU 21, and further includes a memory 50, a display device 23 having a monitor screen 23a and the like, and a keyboard 22a and a mouse 22b as input devices. The function processed by the CPU 21 will be described in a block form. The CPU 21 includes a light transmission / reception unit control unit 40 that controls the light emitting unit 2 and the light detection unit 3, a calculation unit 41, and a brain activity image display unit 44.
The light transmission / reception unit control unit 40 receives light reception signals from the light emission control unit 42 that outputs a drive signal to the light emission unit 2 and the light detection unit 3, and stores light reception signals (light reception amount information) in the memory 50. And a control unit 43.
The light emission control unit 42 performs control to output a drive signal for sequentially transmitting light to the light transmission probe 12 to the light emitting unit 2.
The light detection control unit 43 receives the light reception signal from the light detection unit 3, and stores the 20 measurement data A (λ ₁ ) and A (λ ₂ ) detected from the 20 light reception probes 13 in the memory 50. Control to memorize.

Calculating section 41, measured stored in the memory 50 the data A (lambda _1), in A (lambda _2), a light transmitting probe 12, the measurement data A to the light receiving probe 13 adjacent to the light transmitting probe 12 (lambda ₁ ) And A (λ ₂ ), and based on the acquired measurement data A (λ ₁ ) and A (λ ₂ ), the intensity of transmitted light at each wavelength (oxyhemoglobin absorption wavelength and deoxyhemoglobin absorption wavelength) From this, control is performed to obtain the oxyhemoglobin concentration, deoxyhemoglobin concentration, and total hemoglobin concentration.
The brain activity image display unit 44 performs control to display information on the monitor screen 23a. For example, a contour graph of oxyhemoglobin concentration, deoxyhemoglobin concentration, and total hemoglobin concentration in the brain plane is displayed.

  As described above, according to the holder 11 used in the optical biometric apparatus 1 of the present invention, the interval between the light transmitting probe 12 and the light receiving probe 13 is changed, or the intervals between the measurement sites S are not uniform. Without any problem, it can be in close contact with a surface having various curvatures.

(Other embodiments)
In the optical biometric apparatus 1 described above, the holder 11 having the eleven light transmitting probes 12 and the twenty light receiving probes 13 is shown. However, a holder having a different number of light transmitting probes and light receiving probes may be used.

  INDUSTRIAL APPLICABILITY The present invention can be used for a holder for non-invasively measuring brain activity and an optical biometric apparatus using the holder.

1: Optical biometric apparatus 11: Holder 12: Light transmitting probe 13: Light receiving probe 20: Computer (control unit)
31: Connection part 31a: Insertion part 31b: Connection part 32: Nut part 33: Socket part 41: Calculation part T: Light transmission point R: Light reception point M: Middle point S: Measurement site

  The present invention relates to a holder for non-invasively measuring brain activity and an optical biometric apparatus using the holder.

In recent years, in order to observe the activity state of the brain, an optical brain functional imaging apparatus (optical biometric apparatus) that performs simple noninvasive measurement using light has been developed. In such an optical brain functional imaging apparatus, near-infrared light of two different wavelengths λ ₁ and λ ₂ (for example, 780 nm and 830 nm) is transmitted to the brain by a light transmission probe arranged on the head surface of the subject. , And the intensity (received light amount information) A (λ ₁ ) and A (λ ₂ ) of near-infrared light of each wavelength emitted from the brain is detected by a light receiving probe arranged on the head surface. .
Then, from the received light quantity information A (λ ₁ ) and A (λ ₂ ) thus obtained, the concentration / optical path length product [oxyHb] of oxyhemoglobin in the cerebral blood flow and the concentration / optical path length of deoxyhemoglobin In order to obtain the product [deoxyHb], for example, the simultaneous equations shown in the relational expressions (1) and (2) are created using the Modified Beer Lambert rule, and the simultaneous equations are solved (for example, Non-Patent Document 1). reference). Furthermore, the concentration / optical path length product of total hemoglobin ([oxyHb] + [deoxyHb]) is calculated from the concentration / optical path length product [oxyHb] of oxyhemoglobin and the deoxyhemoglobin concentration / optical path length product [deoxyHb]. Yes.
A (λ ₁ ) = E _O (λ ₁ ) × [oxyHb] + E _d (λ ₁ ) × [deoxyHb] (1)
A (λ ₂ ) = E _O (λ ₂ ) × [oxyHb] + E _d (λ ₂ ) × [deoxyHb] (2)
E _O (λm) is an absorbance coefficient of oxyhemoglobin in light having a wavelength λm, and E _d (λm) is an absorbance coefficient of deoxyhemoglobin in light having a wavelength λm.

Here, the relationship between the distance (channel) between the light transmitting probe and the light receiving probe and the measurement site will be described. FIG. 6A is a cross-sectional view showing a relationship between a pair of light transmitting probe and light receiving probe and a measurement site, and FIG. 6B is a plan view of FIG. 6A.
The light transmitting probe 12 is pressed against the light transmitting point T on the subject's head surface, and the light receiving probe 13 is pressed against the light receiving point R on the subject's head surface. Then, light is emitted from the light transmitting probe 12 and light emitted from the head surface is incident on the light receiving probe 13. At this time, among the light irradiated from the light transmission point T on the head surface, the light that has passed through the banana shape (measurement region) reaches the light receiving point R on the head surface. As a result, the light transmitting point T and the light receiving point R from the middle point M of the line L connecting the light transmitting point T and the light receiving point R at the shortest distance along the head surface of the subject in the measurement region. Received light quantity information A (λ ₁ ), A (λ for the measurement site S of the subject having a depth L / 2 that is half the distance of the line connecting the head and the head along the subject's head surface. ₂ ) is obtained.

In the optical brain functional imaging system, oxyhemoglobin concentration / optical path length product [oxyHb], deoxyhemoglobin concentration / optical path length product [deoxyHb] and total hemoglobin concentration / optical path length product (multiple measurement sites in the brain) In order to measure [oxyHb] + [deoxyHb]), for example, a near-infrared spectrometer is used.
In a near-infrared spectrometer, a holder is used to bring a light-transmitting probe and a light-receiving probe into contact with the subject's head surface in a predetermined arrangement. The holder is provided with a plurality of through-holes, and by inserting the light-transmitting probe and the light-receiving probe into the through-holes, the probe interval between the light-transmitting probe and the light-receiving probe is constant, and a specific distance from the head surface The received light amount information that is the depth is obtained. Note that the probe interval is called a channel, and a channel with a channel of 30 mm is generally used. When the channel is 30 mm, received light amount information with a depth of 15 mm to 20 mm from the midpoint of the channel is obtained. It is believed that. That is, the position at a depth of 15 mm to 20 mm from the head surface substantially corresponds to the brain surface region, and the received light amount information A (λ ₁ ) and A (λ ₂ ) related to the brain activity is obtained.

Here, FIG. 7 is a plan view showing a conventional arrangement of a plurality of light transmitting probes and a plurality of light receiving probes. Fifteen light transmitting probes (black circles) 12 and fifteen light receiving probes (white circles) 13 are arranged in a square lattice pattern so as to alternate in the row direction and the column direction. Then, light is emitted from the light-transmitting probe 12 and the light-receiving probe 13 adjacent to the light-transmitting probe 12 that has emitted the light is detected to detect the light emitted from the head surface, thereby receiving light reception amount information A (λ ₁ ). , A (λ ₂ ). Accordingly, when viewed in plan as shown in FIG. 7, the measurement site (x mark) S is the midpoint between the light transmitting probe 12 and the light receiving probe 13 that receives light from the light transmitting probe 12, for a total of 49 pieces. The received light amount information A (λ ₁ ) and A (λ ₂ ) is collected.

By the way, the curvature of the head surface varies depending on gender differences, age differences, and individual differences. Therefore, the light transmitting probe 12 and the light receiving probe 13 can be easily handled even if there is a difference in curvature of the head surface. The holding parts to be held are arranged in a square lattice pattern on the head surface, and the holding parts are connected by a connecting part exhibiting elasticity within a predetermined range, and further, the rotational variability of the connecting part is set within a predetermined angle. The holder which has is proposed (for example, refer patent document 1).
In addition, a holder made of a holder part that connects the holding portion with a connecting portion that does not exhibit elasticity has also been proposed (see, for example, Patent Document 2). 4 and 5 are diagrams for explaining the holder part. FIG. 4 is an exploded perspective view showing the light transmission probe 12, the nut part 32, the two connection parts 31, and the socket part 33. FIG. 5 is a diagram illustrating the light transmission probe 12, the nut part 32, the two connection parts 31, and the socket part 33 after being assembled.
The holder includes 15 light transmitting probes 12, 15 light receiving probes 13, 30 socket parts 33 for fixing the light transmitting probes 12 and the light receiving probes 13, 49 connection parts 31, and 30 A nut part 32.
The connection part 31 is a plate-shaped body having a single letter shape. And the connection component 31 has the annular-shaped insertion part 31a at both ends, and the connection part 31b which connects the insertion part 31a of both ends with the channel length X. FIG. In the center of each insertion portion 31a, a circular through-hole for inserting the socket component 33 is opened. The connecting portion 31b has a width of 10 mm and a thickness of 0.1 mm, and is formed such that the distance between the center of the through hole and the center of the through hole is a channel length of 30 mm. Only flexible in the direction. That is, the insertion portions 31a at both ends are always held at the channel length X. The material constituting the connection component 31 is not particularly limited, and examples thereof include polypropylene, polyvinyl chloride, and polyacetal.

  7 using the 15 light transmitting probes 12, 15 light receiving probes 13, 30 socket parts 33, 49 connecting parts 31 and 30 nut parts 32. Make it. According to such a holder, as shown in FIG. 5 (a), one connecting component 31 and the other connecting component 31 are socket components as viewed from above in order to be attached so as to be in close contact with the head surface. As shown in FIG. 5 (b), the connecting portion 31b of the connection component 31 is flexible and has a curvature that matches the head surface. It can be deformed to be a surface.

JP 2002-143169 A JP 2009-77841 A

Factors affecting the accuracy of near-infrared spectroscopy concentration calculations for focal changes in oxygenation parameters, NeuroImage 18, 865-879, 2003

However, when a holder using a connecting portion exhibiting elasticity as described above is used, the light-transmitting probe 12 and the light-receiving probe 13 are caused by expansion and contraction of the connecting portion when closely contacting the head surface of various curvatures. As a result, the received light amount information A (λ ₁ ) and A (λ ₂ ) at the depth corresponding to the brain surface region may not be obtained.
In addition, when a holder using a connecting portion that does not exhibit stretchability is used, the distance (channel) between the light transmitting probe 12 and the light receiving probe 13 does not change, but it is closely attached to the head surface with various curvatures. At this time, the square lattice is deformed into a rhombus, and as a result, the intervals between the measurement sites (x marks) S may be uneven.

  In order to solve the above problems, the present inventors have examined the arrangement of the plurality of light transmitting probes 12 and the plurality of light receiving probes 13. As a result, a plurality of light transmitting probes 12 and a plurality of light receiving probes 13 as shown in FIG. 7 are arranged in a square lattice pattern so as to alternate in the row direction and the column direction. It turned out that it was impossible to make it adhere to. Therefore, a hexagon is formed around the pentagon, and pentagons and hexagons are alternately formed around the hexagon. Alternatively, it has been found that the light receiving probe 13 is arranged.

That is, the holder of the present invention is a holder that holds a plurality of light-transmitting probes that irradiate light from the tip and a plurality of light-receiving probes that receive light from the tip and is mounted on the surface of the subject's head. In the holder, a hexagon is formed around the pentagon, and a pentagon and a hexagon are alternately formed around the hexagon, and the vertex of the pentagon and the center of gravity and the vertex of the hexagon are formed. And a through hole into which the light transmitting probe or the light receiving probe is inserted is provided at the position to be the center of gravity, and at the position to be the center of gravity, the light transmitting probe is inserted and at the position to be the top. The light receiving probe is inserted, or the light receiving probe is inserted at the center of gravity, the light transmitting probe is inserted at the top, and the holder Is The holder part comprises a socket part that holds a light transmitting probe or a light receiving probe at both ends, and a connecting part that connects the socket part at a constant interval, The holder part can be rotated with another holder part around the socket part as a rotation axis within the contact surface of the head surface, and has flexibility by the connecting part in the normal direction of the head surface. The holder part is arranged so as to connect the vertex of the pentagon and the center of gravity, is arranged so as to connect the vertex of the hexagon and the center of gravity, and is not arranged so as to connect the vertex of the pentagon and the vertex. At the same time, they are not arranged so as to connect the vertices of the hexagon .

  According to the holder of the present invention, the distance between the light-transmitting probe and the light-receiving probe is not changed, and the distance between the measurement parts does not become non-uniform, so that the holder is in close contact with a surface having various curvatures. Can do.

(Means and effects for solving other problems)
The optical biometric apparatus of the present invention includes a holder as described above, a plurality of light transmitting probes that irradiate light from the tip, a plurality of light receiving probes that receive light from the tip, and the light transmitting probe and the light receiving probe. And a controller for controlling light transmission / reception.

1 is a block diagram showing a schematic configuration of an optical biometric apparatus that is an embodiment of the present invention. The perspective view which shows the net-shaped body with which the mannequin head was mounted | worn. The perspective view which shows schematic structure of a holder. The disassembled perspective view which shows a light transmission probe, a nut component, two connection components, and a socket component. The figure which shows the light transmission probe, nut part, two connection parts, and socket part after an assembly. The figure which shows the relationship between a pair of light transmission probe and light reception probe, and a measurement site | part. The top view which shows the conventional arrangement | positioning of a some light transmission probe and a some light reception probe.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments described below, and it goes without saying that various aspects are included without departing from the spirit of the present invention.

FIG. 1 is a block diagram showing a schematic configuration of an optical biometric apparatus according to an embodiment of the present invention. FIG. 2 is a perspective view showing a net-like body mounted on the mannequin head, and FIG. 3 is a perspective view showing a schematic configuration of the holder. In FIG. 1 and FIG. 3, the light transmitting probe is indicated by a black circle, and the light receiving probe is indicated by a white circle. Moreover, the same code | symbol is attached | subjected about the thing similar to the conventional holder mentioned above.
The optical biometric apparatus 1 includes a holder 11 for mounting on the head surface of a subject, a light emitting unit 2 connected by a light transmission probe 12 and a light guide (not shown), a light receiving probe 13 and a light guide. It is comprised by the photon detection part 3 connected by the optical path (not shown), and the control part (computer) 20 which performs control of the optical biometric apparatus 1 whole.

First, components constituting the holder 11 will be described. FIG. 4 is an exploded perspective view showing the light transmission probe 12, the nut part 32, the two connection parts 31, and the socket part 33.
The holder 11 includes 11 light transmission probes 12, 20 light reception probes 13, 31 socket parts 33 for fixing the light transmission probes 12 and the light reception probes 13, 50 connection parts 31 and 31 pieces. The nut part 32 is provided.

The light transmission probe 12 has an elongated cylindrical shape whose upper end portion is slightly larger to be fixed to the socket component 33. And the upper end part of the light transmission probe 12 is connected with the light emission part 2 via light guides, such as an optical fiber, and irradiates light from a lower end part.
The light receiving probe 13 is also in the shape of an elongated cylinder having a slightly larger upper end similar to the light transmitting probe 12. The upper end of the light receiving probe 13 is connected to the light detection unit 3 via a light guide such as an optical fiber, and receives light at the lower end.

The socket part 33 has a cylindrical main body 33a, an annular jaw 33b, and an annular bottom (contact mechanism) 33c, and the light transmitting probe 12 and the light receiving probe 13 are inserted therein. In addition, a screw (fixing mechanism) to which the nut part 32 is screwed is formed on the outer peripheral surface of the main body portion 33a.
In addition, although it does not specifically limit as a material which comprises the main-body part and jaw part of the said socket component, For example, a polypropylene, a polyvinyl chloride, a polyacetal etc. are mentioned.
Moreover, as a material which comprises the bottom part of the said socket component, if it can closely_contact | adhere to the head surface, it will not specifically limit, For example, sponge etc. are mentioned.
Accordingly, the socket component 33 and the light transmission probe 12 are fixed by inserting the light transmission probe 12 inside the socket component 33. At this time, it fixes so that the bottom face of the bottom part 33c and the lower end surface of the light transmission probe 12 may become the same plane. Therefore, since the bottom 33c is brought into contact with the head surface together with the light transmitting probe 12, the bottom 33c is brought into close contact with the head surface. Furthermore, since the bottom 33c plays a role of pressing the hair or the like, the light transmitting probe 12 can be brought into contact with the head surface by simply inserting the light transmitting probe 12 inside the socket part 33.
Similar to the light transmission probe 12, the light receiving probe 13 is inserted inside the socket component 33, thereby fixing the socket component 33 and the light receiving probe 13.

The nut part 32 has an annular shape having a circular through hole, and a female screw that is screwed into the main body part 33 a of the socket part 33 is formed on the inner peripheral surface thereof. Note that the size of the through hole is larger than the size of the main body portion 33 a of the socket component 33 and smaller than the jaw portion 33 b of the socket component 33 when viewed from above.
The material constituting the nut part is not particularly limited, and examples thereof include polypropylene, polyvinyl chloride, and polyacetal as well as the material constituting the body part and the jaw part of the socket part.
Thus, the insertion portion 31a of the connection component 31 is inserted between the jaw portion 33b of the socket component 33 and the nut component 32 by inserting the main body portion 33a of the socket component 33 into the nut component 32 using a screw mechanism. It can be pinched and fixed. At this time, when fixing one connection component 31, the insertion portion 31 a of one connection component 31 is sandwiched between the jaw portion 33 b of the socket component 33 and the nut component 32. On the other hand, when fixing the five connection parts 31, the insertion parts 31 a of the five connection parts 31 are sandwiched between the jaw parts 33 b of the socket part 33 and the nut parts 32. In other words, an arbitrary number of connection parts 31 can be fixed.

Next, an assembling method for assembling 11 light transmitting probes 12, 20 light receiving probes 13, 31 socket parts 33, 50 connecting parts 31 and 31 nut parts 32 in the holder 11 will be described. (See FIG. 3).
First, a pentagon is formed. The through holes of the insertion parts 31a of the five connection parts 31 are overlapped, and the main body part 33a of the socket part 33 is inserted into the five through holes from below, and further screwed into the through holes of the nut part 32 from below. Insert using mechanism. At this time, one connecting component 31 and the other connecting component 31 are viewed from above by tightening with a screw mechanism so that the five connecting components 31 are sandwiched between the jaw 33b of the socket component 33 and the nut component 32. The socket part 33 can be fixed so as to form a desired angle with the socket part 33 as an axis, but one connection part 31 and the other connection part 31 form 72 ° with the socket part 33 as an axis when viewed from above. Fix it. That is, a regular pentagon is formed by connecting the five insertion portions 31a into which the socket component 33 is not inserted. Further, five insertion portions 31a into which the socket parts 33 are inserted are arranged at the center of gravity of the regular pentagon.

  Next, a hexagon is formed. The through holes of the insertion parts 31a of the six connection parts 31 are overlapped, the main body part 33a of the socket part 33 is inserted into the six through holes from below, and further the screws from below into the through holes of the nut part 32 Insert using mechanism. At this time, one connecting component 31 and the other connecting component 31 are viewed from above by tightening with a screw mechanism so that the six connecting components 31 are sandwiched between the jaw 33b of the socket component 33 and the nut component 32. The socket part 33 can be fixed so as to form a desired angle with the socket part 33 as an axis, but one connection part 31 and the other connection part 31 form 60 ° with the socket part 33 as an axis when viewed from above. Fix it. That is, a regular hexagon is formed by connecting the six insertion portions 31a into which the socket component 33 is not inserted. Further, six insertion portions 31a into which the socket parts 33 are inserted are arranged at the center of gravity of the regular hexagon. And five such hexagons are produced.

  Next, a partial pentagon is formed. The through holes of the insertion parts 31a of the three connection parts 31 are overlapped, and the main body part 33a of the socket part 33 is inserted into the three through holes from below, and further screwed into the through holes of the nut part 32 from below. Insert using mechanism. At this time, one connecting component 31 and the other connecting component 31 are viewed from above by tightening with a screw mechanism so that the three connecting components 31 are sandwiched between the jaw 33b of the socket component 33 and the nut component 32. The socket part 33 can be fixed so as to form a desired angle with the socket part 33 as an axis, but one connection part 31 and the other connection part 31 form 72 ° with the socket part 33 as an axis when viewed from above. Fix it. That is, when three insertion portions 31a into which the socket part 33 is not inserted are connected, a part of a regular pentagon is formed. In addition, at the center of gravity of the regular pentagon, three insertion portions 31a into which the socket parts 33 are inserted are arranged. And five such regular pentagons of a part are produced.

Next, five hexagons are formed around one pentagon. The two insertion portions 31a arranged at the vertex of one side of the pentagon and the two insertion portions 31a arranged at the vertex of one side of the hexagon overlap each other, and the vertex of the other side of the hexagon The jaw part 33b and the nut part 32 of the one socket part 33 are arranged so that the two inserted parts 31a and the two inserted parts 31a arranged at the apex of one side of the other hexagon overlap each other. The insertion parts 31 a of the three connection parts 31 are sandwiched between the insertion parts 31 a and the insertion parts 31 a of the three connection parts 31 are sandwiched between the jaw parts 33 b of the other socket parts 33 and the nut parts 32. In this manner, five hexagons are formed around one pentagon.
Next, a pentagon, a hexagon, a partial pentagon, a partial pentagon, and a hexagon are formed in this order around one hexagon. The two insertion portions 31a arranged at the vertices of one side of a part of the pentagon and the two insertion portions 31a arranged at the vertices of one side of the hexagon overlap each other, and the other side of the part of the pentagon The jaw portion 33b and the nut of one socket part 33 are arranged so that the two insertion portions 31a arranged at the apex of the socket and the two insertion portions 31a arranged at the apex of one side of the other hexagon overlap each other. The insertion parts 31 a of the two connection parts 31 are sandwiched between the parts 32 and the insertion parts 31 a of the two connection parts 31 are sandwiched between the jaw parts 33 b of the other socket parts 33 and the nut parts 32.
As a result, the net-like body shown in FIG. 2 is produced. FIG. 2B shows the net-like body shown in FIG. 2A viewed from another angle.

Then, the produced net-shaped body is mounted on the surface of the head of the subject. At this time, since the head surface of the subject has a curved surface shape, one connecting component 31 and another connecting component 31 are attached as shown in FIG. Is fixed so as to form a desired angle with the socket part 33 as an axis when viewed from above, and the connecting part 31b of the connection part 31 is flexible as shown in FIG. The surface is deformed to have a curvature that matches the surface.
At this time, if the angle formed by the angle between one connection component 31 and the other connection component 31 is fixed in a deformed state, the curvature is maintained.
Finally, the light transmitting probe 12 is inserted inside the socket part 33 arranged at the position where the center of gravity of the pentagon and the center of the hexagon are located, and the socket is arranged at the position where the vertex of the pentagon and the hexagon are located. The holder 11 is manufactured by inserting the light receiving probe 13 inside the component 33.

Next, configurations other than the above-described holder 11 will be described.
The light-emitting unit 2 is a light source that transmits light to one light-transmitting probe 12 selected from among the 11 light-transmitting probes 12 according to a drive signal input from the computer 20, for example, an LED (light-emitting diode). ) And LD (laser diode).
Near-infrared light (for example, 780 nm and 830 nm) is used as the light.
The light detection unit 3 is a detector that outputs 20 received light signals to the computer 20 by individually detecting near-infrared light received by the 20 light receiving probes 13, for example, a photodiode or a phototransistor. A light receiving element such as a photomultiplier tube.

The computer 20 includes a CPU 21, and further includes a memory 50, a display device 23 having a monitor screen 23a and the like, and a keyboard 22a and a mouse 22b as input devices. The function processed by the CPU 21 will be described in a block form. The CPU 21 includes a light transmission / reception unit control unit 40 that controls the light emitting unit 2 and the light detection unit 3, a calculation unit 41, and a brain activity image display unit 44.
The light transmission / reception unit control unit 40 receives light reception signals from the light emission control unit 42 that outputs a drive signal to the light emission unit 2 and the light detection unit 3, and stores light reception signals (light reception amount information) in the memory 50. And a control unit 43.
The light emission control unit 42 performs control to output a drive signal for sequentially transmitting light to the light transmission probe 12 to the light emitting unit 2.
The light detection control unit 43 receives the light reception signal from the light detection unit 3, and stores the 20 measurement data A (λ ₁ ) and A (λ ₂ ) detected from the 20 light reception probes 13 in the memory 50. Control to memorize.

Calculating section 41, measured stored in the memory 50 the data A (lambda _1), in A (lambda _2), a light transmitting probe 12, the measurement data A to the light receiving probe 13 adjacent to the light transmitting probe 12 (lambda ₁ ) And A (λ ₂ ), and based on the acquired measurement data A (λ ₁ ) and A (λ ₂ ), the intensity of transmitted light at each wavelength (oxyhemoglobin absorption wavelength and deoxyhemoglobin absorption wavelength) From this, control is performed to obtain the oxyhemoglobin concentration, deoxyhemoglobin concentration, and total hemoglobin concentration.
The brain activity image display unit 44 performs control to display information on the monitor screen 23a. For example, a contour graph of oxyhemoglobin concentration, deoxyhemoglobin concentration, and total hemoglobin concentration in the brain plane is displayed.

  As described above, according to the holder 11 used in the optical biometric apparatus 1 of the present invention, the interval between the light transmitting probe 12 and the light receiving probe 13 is changed, or the intervals between the measurement sites S are not uniform. Without any problem, it can be in close contact with a surface having various curvatures.

(Other embodiments)
In the optical biometric apparatus 1 described above, the holder 11 having the eleven light transmitting probes 12 and the twenty light receiving probes 13 is shown. However, a holder having a different number of light transmitting probes and light receiving probes may be used.

  INDUSTRIAL APPLICABILITY The present invention can be used for a holder for non-invasively measuring brain activity and an optical biometric apparatus using the holder.

1: Optical biometric apparatus 11: Holder 12: Light transmitting probe 13: Light receiving probe 20: Computer (control unit)
31: Connection part 31a: Insertion part 31b: Connection part 32: Nut part 33: Socket part 41: Calculation part T: Light transmission point R: Light reception point M: Middle point S: Measurement site

Claims (3)

Holding a plurality of light-transmitting probes that irradiate light from the tip and a plurality of light-receiving probes that receive light from the tip, a holder that is attached to the surface of the subject's head,
In the holder, a hexagon is formed around the pentagon, and a pentagon and a hexagon are alternately formed around the hexagon, and the vertex and the center of gravity of the pentagon, the vertex and the center of gravity of the hexagon, Is provided with a through hole into which the light transmitting probe or the light receiving probe is inserted,
The light transmitting probe is inserted at the position to be the center of gravity, and the light receiving probe is inserted at the position to be the apex, or
The holder, wherein the light receiving probe is inserted at a position that becomes the center of gravity, and the light transmission probe is inserted at a position that becomes the apex. The holder is composed of a plurality of holder parts having a single letter shape,
The holder part has a socket part for holding one light transmitting probe or one light receiving probe at both ends, and a connecting part for connecting the socket part at a constant interval,
The holder part can be rotated with another holder part around the socket part as a rotation axis within the contact surface of the head surface, and is flexible by a connecting part in the normal direction of the head surface. The holder according to claim 1, wherein the holder is provided. The holder according to claim 1 or claim 2,
A plurality of light transmitting probes that emit light from the tip;
A plurality of light receiving probes for receiving light from the tip;
An optical biometric apparatus comprising: a control unit that controls light transmission / reception with respect to the light transmission probe and the light reception probe.

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