Light detection unit and brain function measuring apparatus using the same

Abstract

The light detection unit (23) includes a light detector (31) for detecting light, a housing container (71) that is cylindrical and houses the light detector (31), and a flexible substrate (73) on which a signal processing circuit including an A / D converter (33) that converts a light signal detected by the light detector (31) from an analog signal to a digital signal is mounted, the flexible substrate (73) being disposed in a bent and deformed state inside the housing container (71).

Description

Technical Field

[0001] The present invention relates to a light detection unit and a brain function measurement device using the light detection unit, and particularly to a brain function measurement device having a light detection unit disposed on the head of a subject. Background Technology

[0002] Previously, brain function measurement devices were known to observe brain activity by illuminating the head of a subject (e.g., Patent Document 1). Such brain function measurement devices include: a measurement unit installed on the head of the subject; and a main unit connected to the measurement unit via an optical fiber.

[0003] The measurement unit includes: a light irradiation unit that irradiates the brain of the subject with near-infrared light of multiple wavelengths; and a light receiving unit that receives the near-infrared light emitted from the brain after passing through the brain. By comparing the intensity of the light irradiated by the light irradiation unit with the intensity of the light detected by the light detection unit, and measuring the change in light intensity, the activity of cerebral blood flow can be measured.

[0004] The main unit includes a light source (e.g., a light-emitting diode), a light detection unit, and a main control unit that unifies the control of all components. The light detection unit includes: a light detector for detecting light; an amplifier for amplifying the detected light signal; and an A / D converter for converting the amplified light signal into a digital signal. Typically, the amplifier and A / D converter are mounted on a printed circuit board.

[0005] The light source is connected to a light irradiation mechanism, such as a light-emitting probe, via an optical fiber, and the photodetector is connected to a light receiving unit via an optical fiber. That is, near-infrared light emitted from the light source is transmitted to the measurement unit via the optical fiber, and the light irradiation mechanism irradiates the brain of the subject. The near-infrared light emitted from the subject's brain is received by the light receiving unit of the measurement unit, and the received near-infrared light is transmitted to the main unit via the optical fiber. The near-infrared light transmitted to the main unit is detected by the photodetector. In other words, the optical signal is amplified by an amplifier on a printed circuit board, and then converted from an analog signal to a digital signal by an A / D converter. By analyzing the digitally converted optical signal, information related to brain activity can be obtained.

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent Application Publication No. 2017-080479 Summary of the Invention

[0009] The problem the invention aims to solve

[0010] However, in the case of previous examples with such a structure, the following problems exist.

[0011] In conventional structures, after the light received from the measurement unit is transmitted to the main unit, the optical signal, which is an analog signal, undergoes amplification and digital conversion. Therefore, light loss occurs during transmission to the main unit. If the optical signal intensity decreases, the noise ratio increases, resulting in a concern about a reduced signal-to-noise ratio (S / N). Furthermore, transmitting light from the measurement unit to the main unit requires several meters of optical fiber, increasing costs. Additionally, optical fiber has lower durability compared to ordinary cables, necessitating careful use in brain function measurement devices.

[0012] The present invention was made in view of the following circumstances, and its object is to provide a light detection unit capable of improving the S / N ratio of light signals and a brain function measurement device having the light detection unit.

[0013] Solution for solving the problem

[0014] To achieve this objective, the present invention employs the following structure.

[0015] That is, the light detection unit of the present invention comprises: a light detector for detecting light; a cylindrical container for housing the light detector; and a flexible substrate equipped with a signal processing circuit including an A / D converter, the A / D converter converting the light signal detected by the light detector from an analog signal to a digital signal, the flexible substrate being disposed inside the container in a bent and deformed state.

[0016] In this structure, the signal processing circuit, including the A / D converter, is mounted on a flexible substrate, allowing the flexible substrate to be bent and deformed into a smaller shape. Furthermore, by arranging the flexible substrate in a bent and deformed state inside the housing, both the photodetector and the A / D converter are positioned inside the housing. That is, because the photodetector and A / D converter can be positioned closer together, the optical signal detected by the photodetector can be rapidly converted from an analog signal to a digital signal. Therefore, the reduction in optical signal intensity caused by transmitting optical signals in analog form can be avoided, enabling miniaturization of the photodetector unit and improving the signal-to-noise ratio (S / N) of the optical signal.

[0017] Furthermore, preferably, in the above-described invention, the flexible substrate includes: a first portion connected to the photodetector; a second portion on which a signal processing circuit including the A / D converter is mounted; and a connecting portion connecting the first portion and the second portion, wherein the connecting portion is bent in an orthogonal manner to the first portion and the second portion and the second portion is bent and deformed, thereby deforming the flexible substrate into a cylindrical shape along the inner surface of the storage container.

[0018] [Function / Effect] According to the optical detection unit of the present invention, bending the connecting portion that connects the first and second portions of the flexible substrate and bending the second portion deforms the flexible substrate, thereby enabling the flexible substrate to be deformed into a cylindrical shape along the inner surface of the storage container. Therefore, a flat flexible substrate can be deformed into a smaller cylindrical shape. Furthermore, according to this structure, due to the restoring force of the second portion attempting to return to its original shape, the flexible substrate exerts a pressing force on the inner surface of the storage container. Under this pressing force, the flexible substrate is held inside the storage container; therefore, the flexible substrate can be stably held inside the storage container without the use of screws or other fasteners.

[0019] Furthermore, preferably, in the above-described invention, the flexible substrate includes: a first portion connected to the photodetector; a second portion on which a signal processing circuit including the A / D converter is mounted; and a connecting portion connecting the first portion and the second portion, wherein the connecting portion is bent in such a manner that the first portion and the second portion overlap, thereby deforming the flexible substrate into a folded state inside the storage container.

[0020] [Function / Effect] According to the optical detection unit of the present invention, bending the connecting portion that connects the first and second portions of the flexible substrate causes the first and second portions to overlap, thereby enabling the flexible substrate to be deformed into a folded state inside the storage container. Therefore, the flat flexible substrate can be deformed into a smaller shape. Consequently, the volume occupied by the flexible substrate can be further reduced, and thus the optical detection unit can be further miniaturized.

[0021] In addition, the present invention may also adopt the following structure to achieve this objective.

[0022] That is, the brain function measurement device of the present invention comprises: a measurement unit having the light detection unit described above and a light irradiation unit for irradiating light onto the brain of the subject, the measurement unit being mounted on the head of the subject; and a main body unit electrically connected to the measurement unit and having a brain function measurement unit that obtains measurement data related to the brain activity of the subject based on the light signal digitally converted by the A / D converter.

[0023] [Function / Effect] According to the brain function measurement device of the present invention, by making the substrate equipped with the A / D converter a flexible substrate, the substrate can be bent and deformed to be disposed inside the storage container of the light detection unit. Therefore, the light detection unit can be miniaturized, and thus, the light detection unit can be disposed on the measurement unit side mounted on the head of the subject instead of on the main unit side.

[0024] According to this structure, light illuminating the brain of the subject from the light illumination unit is rapidly converted into a digital signal by an A / D converter after being detected by the photodetector in the light detection unit. Therefore, the reduction in light signal intensity caused by transmitting light signals in analog form can be avoided, thus improving the signal-to-noise ratio (S / N) of the light signal. As a result, the accuracy of brain function measurement data can be further improved.

[0025] The effects of the invention

[0026] According to the present invention, the optical detection unit and the brain function measurement device equipped with the optical detection unit include a signal processing circuit, including an A / D converter, mounted on a flexible substrate. Therefore, the flexible substrate can be bent and deformed to achieve a smaller shape. Furthermore, by arranging the flexible substrate in a bent and deformed state inside the storage container, both the optical detector and the A / D converter are disposed inside the storage container. That is, since the optical detector and the A / D converter can be arranged closer together, the optical signal detected by the optical detector can be rapidly converted from an analog signal to a digital signal. Therefore, the reduction in optical signal intensity caused by transmitting the optical signal in an analog signal state can be avoided, the optical detection unit can be miniaturized, and the signal-to-noise ratio (S / N ratio) of the optical signal detected by the optical detection unit can be improved. Attached Figure Description

[0027] Figure 1 This is a perspective view illustrating the overall structure of the brain function measurement device of Embodiment 1.

[0028] Figure 2 This is a functional block diagram illustrating the structure of the brain function measurement device in Embodiment 1.

[0029] Figure 3 This is a cross-sectional view showing the positional relationship between the paired light-transmitting probe and light-receiving probe of Example 1 and the measurement site in the brain.

[0030] Figure 4 This is a cross-sectional view illustrating the structure of the probe unit holder in Embodiment 1.

[0031] Figure 5 This is a perspective view showing the state in which the cover member is installed on the main body of the probe unit of Embodiment 1.

[0032] Figure 6 This is a perspective view showing the state of the probe unit body of Embodiment 1 with the cover component removed.

[0033] Figure 7 Along the main body of the probe unit in Embodiment 1 Figure 6 A sectional view of line A-A.

[0034] Figure 8 This is a perspective view illustrating the structure of the holding member of the probe unit in Embodiment 1.

[0035] Figure 9 This is a perspective view illustrating the state of the holding member and main body of the probe unit in embodiment 1.

[0036] Figure 10 This is a longitudinal sectional view of the light detection unit in Embodiment 1.

[0037] Figure 11 This is a top view of the flexible substrate of Example 1.

[0038] Figure 12 This is a perspective view showing the state in which the second part of the flexible substrate of Embodiment 1 is raised.

[0039] Figure 13 This is a perspective view showing the state in which the second part of the flexible substrate of Embodiment 1 is bent into a cylindrical shape.

[0040] Figure 14 This is a perspective view showing the state of the light detection unit assembled in Embodiment 1.

[0041] Figure 15 This is a longitudinal sectional view of the light detection unit in Embodiment 1.

[0042] Figure 16 This is a top view of the flexible substrate of Example 2.

[0043] Figure 17 This is a perspective view showing the state in which the second part of the flexible substrate of Embodiment 2 is raised.

[0044] Figure 18 This is a perspective view showing the state in which the second part of the flexible substrate of Embodiment 2 is bent into a cylindrical shape.

[0045] Figure 19 This is a longitudinal sectional view of the light detection unit in Embodiment 2.

[0046] Figure 20 This is a top view of the flexible substrate of Example 3.

[0047] Figure 21 This is a perspective view showing the state in which the flexible substrate of Embodiment 2 is deformed into a columnar shape by bending the connecting parts.

[0048] Figure 22 This is a longitudinal sectional view of the light detection unit in Embodiment 3.

[0049] Figure 23 This is a longitudinal sectional view of the optical detection unit of the modified example. Detailed Implementation

[0050] Example 1

[0051] Hereinafter, Embodiment 1 of the present invention will be described with reference to the accompanying drawings.

[0052] <Explanation of the overall structure>

[0053] like Figure 1 As shown, the brain function measurement device 1 of Embodiment 1 includes a measurement unit 3 and a main unit 5. The measurement unit 3 and the main unit 5 are electrically connected via a cable 6. The measurement unit 3 is mounted on the head of the subject M. In this embodiment, a portable computer is used as the main unit 5.

[0054] The measuring unit 3 includes a probe unit 7 and a probe unit holder 8. The probe unit holder 8 holds the probe unit 7. The probe unit holder 8 has a shape that covers the head of the subject M and is made of a light-shielding material. As an example of the material used to make the probe unit holder 8, a helmet-shaped resin can be cited. By attaching the probe unit holder 8 to the head of the subject M, the probe unit 7 is held on the head of the subject M.

[0055] The position and number of probe units 7 disposed on the probe unit holder 8 are varied according to the part of the brain of the subject M whose function needs to be measured. In this embodiment, as... Figure 1 As shown, four probe units 7 are held in a probe unit holder 8. The probe unit holder 8 has a fixing strap (not shown). With the probe unit holder 8 mounted on the head of the subject M, the fixing strap is further installed on the head of the subject M, thereby fixing the probe unit holder 8 to the head of the subject M.

[0056] like Figure 1 and Figure 2 As shown, the main unit 5 includes a main control unit 9, an operation unit 11, a storage unit 13, and a display unit 15. For example, the main control unit 9 includes an information processing unit such as a central processing unit (CPU). The main control unit 9 centrally controls all structures of the brain function measurement device 1.

[0057] The operation unit 11 is used to input operator instructions related to the operation of the brain function measurement device 1. Based on the operator's input to the operation unit 11, the main control unit 9 performs unified control. In this embodiment, a computer keyboard is used as the operation unit 11. Examples of operation units 11, besides a keyboard, include touch panels, mice, DIP switches, and push-button switches.

[0058] The storage unit 13 stores various programs executed by the main control unit 9, as well as various information, such as various data measured by the measurement unit 3. A non-volatile memory can be cited as an example of the storage unit 13. The display unit 15 displays the measurement conditions of the measurement unit 3, as well as various information, such as various data measured by the measurement unit 3. A liquid crystal display (LCD) can be cited as an example of the display unit 15.

[0059] like Figure 2 As shown, the probe unit 7 includes a light output device 17, a light transmitting probe 19, a light receiving probe 21, and a light detection unit 23. In this embodiment, the probe unit 7 includes two light transmitting probes 19 and two light receiving probes 21. The number of light transmitting probes 19 and light receiving probes 21 included in the probe unit 7 can also be appropriately changed.

[0060] The light output device 17 is a light source that generates light, and for example, it outputs near-infrared light with wavelengths of 780nm, 805nm, and 830nm. Examples of light output devices 17 include light-emitting diodes (LEDs) or semiconductor lasers. The light output device 17 is connected to the light-transmitting probe 19 using an optical transmission component, such as an optical fiber, so that the light generated by the light output device 17 is transmitted to the light-transmitting probe 19.

[0061] The light-emitting probe 19 has a shape that extends in one direction. One end of the light-emitting probe 19 is connected to the light output device 17, and the other end of the light-emitting probe 19 is configured to contact the scalp 25 of the subject M. Figure 3 As shown, the light-emitting probe 19 emits light towards the subject M while in contact with the scalp 25 of the subject M. The light emitted from the light-emitting probe 19 is transmitted to the brain region 29 of the subject M via the scalp 25 and the skull 27. An example of a material constituting the light-emitting probe 19 is a light guide with a columnar glass component. Therefore, the light output device 17 and the light-emitting probe 19 constitute a light irradiation unit 20 that irradiates light into the brain of the subject M.

[0062] The light receiving probe 21 has the same structure as the light transmitting probe 19. That is, the light receiving probe 21 has a shape that extends in one direction, and for example, it is constructed of a light guide with a columnar glass component. One end of the light receiving probe 21 is connected to the light detection unit 23, and the other end of the light receiving probe 21 is configured to contact the head skin 25 of the subject M. The light receiving probe 21 is configured to receive light and transmit the received light to the light detection unit 23.

[0063] The diameter of one end of the light receiving probe 21 is larger than the diameter of the through hole 72 described later. Furthermore, the diameter of the other end of the light receiving probe 21 is smaller than the diameter of the through hole 72. That is, the other end of the light receiving probe 21 is configured to pass through the through hole 72 provided in the storage container 71.

[0064] The light detection unit 23 includes a light detector 31 and an A / D converter 33. The light detector 31 detects the light received by the light receiving probe 21 and amplifies the light signal. Examples of light detectors 31 include photomultiplier tubes or photodiodes. The A / D converter 33 converts the amplified light signal detected by the light detector 31 from an analog signal into a digital signal. As described later, the A / D converter 33 is mounted on a flexible substrate 73. The A / D converter 33 corresponds to the A / D converter of the present invention.

[0065] The measurement unit 3 also includes a measurement unit control unit 35. The measurement unit control unit 35 is a computer comprising a processor and memory. The measurement unit control unit 35 controls various structures within the measurement unit 3, such as the light output unit 17 and the light detection unit 23. The measurement unit control unit 35 receives control from the main control unit 9 and controls the various structures within the measurement unit 3. The measurement unit control unit 35 is connected to the light illumination unit 20 via a cable 18. Furthermore, the measurement unit control unit 35 is connected to the light detection unit 23 via a cable 18.

[0066] <Measurement operation using brain function measurement device>

[0067] Here, the operation of measuring the brain function of subject M using brain function measuring device 1 will be described. When performing measurements using brain function measuring device 1, as follows... Figure 3 As shown, the light-emitting probe 19 and the light-receiving probe 21 are brought into contact with the head skin 25 of the subject M. Then, the measurement light L in the near-infrared light region output from the light output device 17 is emitted from the light-emitting probe 19 toward the head skin 25.

[0068] In addition, such as Figure 3 As shown, with the probe unit 7 held in the probe unit holder 8 as a reference, the direction toward the head skin 25 is designated as the z1 direction, and the direction away from the head skin 25 is designated as the z2 direction. Hereinafter, the z1 direction and the z2 direction are combined as the z direction. Furthermore, the plane orthogonal to the z direction is designated as the xy plane, and the two directions orthogonal to the xy plane are designated as the x direction and the y direction.

[0069] The measuring light L emitted from the scalp 25 reaches the brain region 29 via the skull 27, with a portion of the measuring light L passing through the brain region 29. The measuring light L emitted from the scalp 25 after passing through the brain region 29 is then directed towards the light receiving probe 21. At this point, a banana-shaped measuring channel CH is formed by the area between a light transmitting probe 19 and a light receiving probe 21 that serves as the path for the measuring light L.

[0070] The measurement light L received by the light receiving probe 21 is transmitted to the light detection unit 23. The measurement light L is detected by the light detector 31 located in the light detection unit 23. Furthermore, the detection signal of the measurement light L is amplified in the light detector 31. The amplified detection signal of the measurement light L is converted into a digital signal by the A / D converter 33. The digitally converted detection signal is transmitted to the main unit 5 via the cable 6. The main control unit 9 calculates measurement data representing the brain activity of the subject M based on the digital signal data.

[0071] Specifically, if reflecting the brain activity of the subject M, the amount of hemoglobin in the blood of the brain increases at the activated sites, and the absorption of the measuring light L by hemoglobin increases. Therefore, the change in the amount of hemoglobin with brain activity can be obtained based on the intensity of the measured light L. Furthermore, for hemoglobin, oxyhemoglobin formed by binding with oxygen and deoxyhemoglobin that is not bound to oxygen have different light absorption characteristics. Therefore, the brain function measurement device 1 uses a measuring light L with multiple wavelengths (for example, 780 nm, 805 nm, and 830 nm) that take into account the differences in light absorption characteristics for measurement.

[0072] The main control unit 9 calculates the time-varying concentrations of oxyhemoglobin and deoxyhemoglobin based on the intensity of the measurement light L at various wavelengths received by the light receiving probe 21. Based on the calculated time-varying concentrations of each hemoglobin, changes in blood flow and the activation state of oxygen metabolism in the brain of the subject M can be obtained non-invasively. The main control unit 9 corresponds to the brain function measurement unit of this invention.

[0073] The measurement unit 3 is equipped with multiple light-emitting probes 19 and multiple light-receiving probes 21. By using the multiple light-emitting probes 19 and multiple light-receiving probes 21 to measure brain regions 29 in multiple measurement channels CH, it is possible to obtain data representing a two-dimensional distribution of brain activity.

[0074] As an example, brain function measurement is initiated by inputting commands through the operation unit 11. When the operator inputs various measurement-related instructions using the operation unit 11, the main control unit 9 controls the measurement unit control unit 35 to initiate the measurement. If the measurement begins, the measurement unit control unit 35 controls the light output unit 17 to sequentially output measurement light L to each light-emitting probe 19 at a predetermined cycle.

[0075] Synchronously with the output measurement light L from the light output unit 17, the measurement unit control unit 35 controls the light detection unit 23. That is, the measurement unit control unit 35 controls the light detection unit 23 so that the light receiving probe 21, which forms the measurement channel CH with the light sending probe 19 that outputs the measurement light L, detects the measurement light L. Furthermore, the measurement unit control unit 35 sends the detection signal of the measurement light L detected by the light detection unit 23 to the main control unit 9.

[0076] The main control unit 9 analyzes the changes in hemoglobin levels with brain activity based on the detection signal of the measuring light L, and displays the measurement results on the display unit 15. After performing the predetermined task, the operator inputs an instruction to the operation unit 11 to end the brain function measurement. When the input operation to end the measurement is performed, the main control unit 9 controls the measurement unit control unit 35 to end the measurement, thereby ending a series of actions related to the brain function measurement.

[0077] <Structure of the probe unit holder>

[0078] Here, use Figure 4 The structure of the probe unit holder 8 and the structure connecting the probe unit holder 8 and the probe unit 7 will be described. Figure 4 This is a longitudinal sectional view of the probe unit holder 8.

[0079] The probe unit 7 includes a main body 39, a holding member 41, and a connecting member 43. The probe unit holding member 8 includes a connecting member holding portion 47 and an opening 49. The main body 39 has an overall cylindrical structure, housing the light output device 17 and the light detection unit 23. The detailed structure of the main body 39 will be described later. The holding member 41 holds the main body 39. The connecting member 43 is disposed on the holding member 41 and is a curved plate-shaped member.

[0080] A connecting member retaining portion 47 is disposed on the back side of the top of the probe unit retainer 8, retaining the connecting member 43. That is, the plate-shaped connecting member 43 is connected to the retainer 41 at one end and to the connecting member retaining portion 47 at the other end. Therefore, the probe unit 7 and the probe unit retainer 8 are connected via the connecting member 43. An opening 49 is provided on the probe unit retainer 8 near the position where each probe unit 7 is disposed, and the connecting member 43 passes through the opening 49.

[0081] like Figure 4 As shown, the connecting member 43 is arranged in a bent state, protruding in the direction indicated by reference numeral P1. Reference numeral P1 indicates the direction from the head surface 25 of the subject M toward the inner circumferential surface of the probe unit holder 8; in other words, it corresponds to the direction opposite to the head skin 25 of the subject M. Furthermore, reference numeral P2 indicates the direction from the inner circumferential surface of the probe unit holder 8 toward the head surface 25 of the subject M. Direction P2 corresponds to the direction opposite to direction P1.

[0082] The connecting member 43 is configured to elastically deform in directions P1 and P2. Therefore, when the measuring unit 3 is installed on the subject M, if the head skin 25 of the subject M presses the probe unit 7 in direction P1, a pressing force in direction P2 is applied to the probe unit 7 due to the restoring force caused by the elastic deformation. That is, the pressing force in direction P2 is generated due to the elastic deformation of the connecting member 43, thereby pressing the probe unit 7 against the head skin 25 of the subject M. As a result, the light-transmitting probe 19 and the light-receiving probe 21 can reliably contact the head skin 25.

[0083] <Structure of the probe unit>

[0084] The structure of probe unit 7 will be described in more detail. For example... Figure 5 and Figure 6 As shown, the main body 39 of the probe unit 7 includes a base member 51, a cover member 53, a central shaft 55, a rotating shaft 57, a comb-shaped member 59, and a holding part 61.

[0085] The base member 51 holds the light output device 17 and the light detection unit 23. In this embodiment, the base member 51 uses a circular plate-shaped member. Furthermore, in this embodiment, as... Figure 6 As shown, the base member 51 holds the light output device 17 and the light detection unit 23 with the z-direction being the direction in which the light output device 17 and the light detection unit 23 extend. At this time, the surface of the base member 51 is parallel to the xy plane.

[0086] The cover member 53 is a cylindrical member with an opening in the z1 direction, configured to cover the light output device 17 and the light detection unit 23 held by the base member 51 from the outside. A groove 51a is formed at the periphery of the base member 51, and the side of the cover member 53 with the opening is fitted with the groove 51a.

[0087] A central axis 55 is vertically positioned at the center of the base member 51. The main body 39 is configured to rotate about the axis of the central axis 55. A rotation shaft 57 is disposed on the side of the base member 51 and is configured to protrude outward toward the outside of the base member 51. The rotation shaft 57 is configured to rotate about its axis 58. The base member 51 is configured to rotate together with the rotation shaft 57 about its axis 58. That is, by rotating the rotation shaft 57 about its axis 58, the main body 39 can be displaced in an inclined manner relative to the xy plane.

[0088] The comb-shaped member 59 is composed of multiple pin-shaped members. The comb-shaped member 59 is configured to protrude from the base member 51 of the main body 39 in the z1 direction. For example... Figure 3 As shown, the comb-like member 59 is configured to part the hair 26 of the subject M. The comb-like member 59 is made of a material that can be elastically deformed. Examples of materials for the comb-like member 59 include slender rod-shaped resins that are suitable for parting the hair 26.

[0089] During brain function measurement, the main body 39 is rotated around the central axis 55, causing the comb-like member 59 to part the hair 26 of the subject M. By parting the hair 26 with the comb-like member 59, the light-transmitting probe 19 and the light-receiving probe 21 can reliably contact the scalp 25 without being obstructed by the hair 26. The tip of the comb-like member 59 has a smooth surface with rounded corners. By having a smooth surface with rounded corners, damage to the scalp 25 can be avoided when the comb-like member 59 parts the hair 26.

[0090] The grip 61 consists of two arc-shaped components positioned opposite each other about the central axis 55. The operator grips the grip 61, thereby enabling the main body 39 to rotate about the central axis 55.

[0091] Figure 7 yes Figure 6 The cross-sectional view along line A-A of the main body 39 is shown. Figure 7 As shown, the base member 51 has the same number of through holes 51b as the light-transmitting probe 19 and the light-receiving probe 21. Furthermore, an elastic member 51c is provided on the inner circumferential surface of the through holes 51b of the base member 51. By engaging the fitting portion 71b (described later) with the through hole 51b provided with the elastic member 51c, the light-transmitting probe 19 and the light-receiving probe 21 are respectively held in the base member 51.

[0092] The elastic member 51c is configured to elastically deform along the z-direction inside the through hole 51b. Examples of materials that make up the elastic member 51c include springs. Due to the restoring force caused by the elastic deformation of the elastic member 51c, forces in the z-direction are applied to the light-transmitting probe 19 and the light-receiving probe 21, respectively.

[0093] like Figure 8 As shown, the retaining member 41 of the probe unit 7 has an opening 41a. The retaining member 41 is configured to retain the main body portion 39 inside the opening 41a. In this embodiment, the retaining member 41 has an annular shape, but the shape of the retaining member 41 can be appropriately changed. Figure 9 As shown, the retaining member 41 is configured to be divisible into a first member 63 and a second member 64 in the direction through which the main body portion 39 passes (the z-direction in this embodiment). By dividing the retaining member 41 into the first member 63 and the second member 64, the main body portion 39 is configured to be detachable relative to the retaining member 41. The connecting member 43 is connected to the first member 63 in the retaining member 41.

[0094] Recesses 65 are formed at the periphery of the first member 63 and the second member 64. By combining the first member 63 and the second member 64, the recesses 65 respectively provided in the first member 63 and the second member 64 are combined to form a through hole 66. The through hole 66 is configured to allow the rotating shaft 57 to pass through.

[0095] That is, the first member 63 and the second member 64 are configured to hold the rotation shaft 57 in a direction through which the main body 39 passes. Furthermore, by combining the first member 63 and the second member 64 in such a manner that the rotation shaft 57 is held, the rotation shaft 57 can rotate about the axis 58 while the holding member 41 holds the main body 39. By rotating the rotation shaft 57, the main body 39 can move in a direction inclined relative to the xy plane. Regarding the direction in which the main body 39 tilts due to the rotation of the rotation shaft 57, in Figure 4 The figure is indicated by the symbol F.

[0096] <Structure of the optical detection unit>

[0097] use Figures 10 to 15 The structure of the light detection unit 23 will be described below. The light detection unit 23 includes a housing 71 and a flexible substrate 73. The housing 71 is a cylindrical component that houses the light detector 31 and the flexible substrate 73. In this embodiment, the housing 71 uses a cylindrical component. Furthermore, Figure 15 This is a longitudinal sectional view of the photodetector unit 23. The exception is that the photodetector 31 and the flexible substrate 73 are partially cut off sectional views.

[0098] The storage container 71 has a structure in which a body portion 71a and a fitting portion 71b are connected. The fitting portion 71b is a cylindrical member with a smaller diameter than the body portion 71a. By fitting the fitting portion 71b into the through hole 51b of the base member 51 and by having the lower surface of the body portion 71a abut against the upper surface of the base member 51, the base member 51 stably holds the storage container 71 of the light detection unit 23.

[0099] like Figure 10 As shown, the photodetector 31 is disposed on the inner bottom surface of the storage container 71, and a flexible substrate 73 is disposed on the photodetector 31 in a welded state. Figure 10 This is a longitudinal sectional view of the light detection unit 23, but for ease of explanation, the light detector 31 and the flexible substrate 73 are shown as a side view. As described later, the flexible substrate 73 is disposed on the light detector 31 in a cylindrical state that is deformed along the inner surface of the receiving container 71.

[0100] A through hole 72 is formed at the lower part of the fitting portion 71b. The light receiving probe 21 is held in place by the housing 71 by passing through the through hole 72. Furthermore, the light receiving probe 21 passes through the through hole 72 in a manner that abuts against the photodetector 31. That is, in the light detection unit 23, the light receiving probe 21 abuts against the photodetector 31, and the photodetector 31 abuts against the flexible substrate 73.

[0101] use Figures 11 to 15 The structure of the flexible substrate 73 will be described. Figure 11 This is a top view of the flexible substrate 73 in its initial state. In its initial state, the flexible substrate 73 is generally flat. The flexible substrate 73 is made of a flexible material, and each part of the flexible substrate 73 is configured to be bent and deformed.

[0102] The flexible substrate 73 includes a first portion 75, a second portion 77, and a connecting portion 79. The first portion 75 is the portion connected to the photodetector 31 and has a mounting portion 75a. The mounting portion 75a is the portion for soldering the wiring 81 of the photodetector 31. By soldering the wiring 81 to the mounting portion 75a, the photodetector 31 is mounted to the first portion 75 of the flexible substrate 73. Furthermore, when the flexible substrate 73 is deformed into a cylindrical shape, the first portion 75 constitutes the bottom of the cylindrical flexible substrate 73. The first portion 75 is configured with a shape and size that can be disposed on the inner bottom surface of the storage container 71. In Embodiment 1, the first portion 75 has a circular plate shape.

[0103] An A / D converter 33, a transmission circuit 83, and a connector portion 85 are mounted on the surface (circuit mounting surface) of the second portion 77. When the flexible substrate 73 is deformed into a cylindrical shape, the second portion 77 constitutes the side periphery of the cylindrical flexible substrate 73. In Embodiment 1, the second portion 77 is a rectangle extending in the y-direction.

[0104] The connecting portion 79 connects the first portion 75 and the second portion 77. In Embodiment 1, the connecting portion 79 is rectangular, extending along the x-direction. The shapes of the first portion 75, the second portion 77, and the connecting portion 79 can also be appropriately modified according to the shape of the inner surface of the storage container 71. In addition to the A / D converter 33, the transmission circuit 83, and the connector portion 85, the second portion 77 is also appropriately equipped with wiring 82 connecting each circuit and a signal processing circuit for processing the detection signal of the measurement light L. Examples of signal processing circuits include amplifier circuits that amplify the detection signal of the measurement light L.

[0105] The transmission circuit 83 is a circuit for transmitting the detection signal of the measurement light L, which has been digitally converted by the A / D converter 33. In Embodiment 1, the transmission circuit 83 uses a Serial Peripheral Interface (SPI) for serial communication. The connector section 85 is a device that connects the measurement unit control section 35 and the flexible substrate 73 via the cable 18. The detection signal of the measurement light L detected by the photodetector 31 is quickly converted into a digital signal by the A / D converter 33 after being sent to the flexible substrate 73. The digitally converted detection signal is transmitted to the main unit 5 via the transmission circuit 83, the connector section 85, and the cable 6.

[0106] <The process of storing flexible substrates>

[0107] use Figures 12 to 15 The process of deforming the flexible substrate 73 and housing it in the storage container 71 will be described. First, regarding... Figure 11 The flat flexible substrate 73 shown is bent so that the second portion 77 is in an upright state. Figure 12 The flexible substrate 73 is shown with the second part 77 in an upright state.

[0108] After the second part 77 is brought into an upright position, it is deformed by bending the two wings (the two ends in the longitudinal direction) of the second part 77 inward. By bending the two wings of the second part 77, it is thus deformed as follows: Figure 13 As shown, the second part 77 is deformed into a cylindrical shape. By deforming the second part 77 into a cylindrical shape, the flexible substrate 73 is deformed into a cylindrical body with an opening 76, where the first part 75 is the bottom surface and the second part 77 is the side surface.

[0109] The circuit mounting surface of the second portion 77, which is deformed into a cylindrical shape, and which houses the A / D converter 33, is configured to become the inner peripheral surface of the cylindrical body formed by the second portion 77. Consequently, the outer peripheral surface of the cylindrical body formed by the second portion 77 becomes a flat surface without any circuitry mounted. Furthermore, the flexible substrate 73, which is deformed into a cylindrical shape, has an opening 76 in the z2 direction. Therefore, a cable 18 can be connected from the outside of the flexible substrate 73 to the connector portion 85 via the opening 76.

[0110] After deforming the flexible substrate 73 into a cylindrical shape, as Figure 14 As shown, a light detection unit 23 is formed by combining a light receiving probe 21, a light detector 31, a flexible substrate 73, and a housing 71. First, the other end of the light receiving probe 21 is inserted through a through-hole 72 in the fitting portion 71b of the housing 71 from above. Since the diameter of one end of the light receiving probe 21 is larger than the diameter of the through-hole 72, therefore, as... Figure 10 As shown, this design prevents the light receiving probe 21 from passing through the through hole 72 and falling out of the housing 71. Therefore, the light receiving probe 21 is stably held by the housing 71.

[0111] After assembling the light receiving probe 21 and the housing 71, the photodetector 31 is mounted on the inner bottom surface of the housing 71, which extends in the z-direction. The mounted photodetector 31 is connected to one end of the light receiving probe 21, which protrudes upward from the through-hole 72. After mounting the photodetector 31 on the inner bottom surface of the housing 71, which extends in the z-direction, the flexible substrate 73, which is deformed into a cylindrical shape, is housed inside the housing 71 in the z-direction. At this time, the photodetector 31 and the flexible substrate 73 are connected by soldering the wiring 81 of the photodetector 31 and the mounting portion 75a of the first part 75.

[0112] As the material of the flexible substrate 73, a material with elastic force is used, so that when the flexible substrate 73, which is initially flat, is deformed into a cylindrical shape, a restoring force G acts at the second portion 77 that is bent and deformed into a cylindrical shape, which aims to restore it to a flat shape. That is, when the flexible substrate 73, which is deformed into a cylindrical shape, is housed inside the housing container 71, a restoring force G acts on the inner surface of the housing container 71 from the flexible substrate 73. This restoring force G acts in the direction of pressing the inner surface of the housing container 71 outward. Therefore, by the application of the restoring force G, the flexible substrate 73 can be stably held inside the housing container 71 without using fasteners such as screws.

[0113] The light detection unit 23 of Embodiment 1 has a structure in which a photodetector 31 and a flexible substrate 73 are housed inside a housing 71. The photodetector 31 detects the measurement light L and transmits a detection signal, and the flexible substrate 73 has an A / D converter 33 that converts the detection signal of the measurement light L from an analog signal to a digital signal. Therefore, in the light detection unit 23, the photodetector 31 and the A / D converter 33 are in a close proximity, thus enabling rapid digital conversion of the detection signal of the measurement light L received by the light receiving probe 21. In other words, the distance for transmitting the measurement light L before digital conversion can be significantly shortened, thereby avoiding the reduction in the measurement light L caused by transmitting the measurement light L as an analog signal. As a result, the signal-to-noise ratio (S / N ratio) of the signal detected by the light detection unit 23 can be improved.

[0114] Furthermore, in brain function measurement devices, the goal is for the measurement unit mounted on the head of the subject M to be small and lightweight. Therefore, in the brain function measurement device 1 of the present invention, by deforming the flexible substrate 73 into a cylindrical shape, the area occupied by the flexible substrate 73, which is initially flat, can be significantly reduced. That is, since the size of the light detection unit 23 can be kept small, and the flexible substrate 73 with the A / D converter 33 is housed inside the light detection unit 23, both the S / N ratio at the light detection unit 23 and the miniaturization of the light detection unit 23 can be achieved.

[0115] The receiving container 71 is a cylindrical shape extending along the z-direction, housing the photodetector 31 and the flexible substrate 73, which is deformed into a cylindrical shape extending along the z-direction, in a z-direction-connected state. With this structure, the photodetector unit 23 is integrally shaped to extend along the z-direction, thus reducing the area occupied by the flexible substrate 73 and the photodetector unit 23 in the xy-plane. In other words, since the area occupied by the photodetector unit 23 on the surface of the scalp 25 of the subject M can be reduced, the number of measurement channels CH for measuring the brain function of the subject M in the brain function measurement device 1 can be further increased.

[0116] In the brain function measurement device 1 of Embodiment 1, the flexible substrate 73 equipped with the A / D converter 33 is deformed into a small storage container 71 housed in the light detection unit 23. Therefore, in the brain function measurement device 1, the light detector 31 and the A / D converter 33 can be disposed on the measurement unit 3 side mounted on the head of the subject M instead of on the main body unit 5 side.

[0117] That is, in the brain function measurement device 1, a series of signal processing steps, such as detection of the measurement light L, amplification of the light detection signal, and digital conversion of the light detection signal, can be performed on the measurement unit 3 side. Therefore, unlike conventional devices that perform digital conversion of the light detection signal on the main unit side, the brain function measurement device 1 of Embodiment 1 does not require an optical fiber connection between the measurement unit 3 and the main unit 5. That is, a conventional electrical signal transmission cable can be used as the cable 6, thus avoiding the increased cost and reduced durability of the signal transmission components caused by the extensive use of optical fibers.

[0118]

Example 2

[0119] Next, use Figures 16 to 19 Embodiment 2 of the present invention will be described. In Embodiment 2, the structure of the flexible substrate 73 differs from that of Embodiment 1. Therefore, the flexible substrate 73 of Embodiment 2 is marked with reference numeral 73A to distinguish it from the flexible substrate 73 of Embodiment 1. On the other hand, the same reference numerals are used to illustrate structures common to Embodiment 1, and their descriptions are omitted. Figure 19 and Figure 15 Similarly, this is a cross-sectional view of a partial cut-out of the photodetector 31 and the flexible substrate 73A.

[0120] Figure 16 This is a top view of the flexible substrate 73A of Embodiment 2. In its initial state, the flexible substrate 73A has an overall cross-shaped flat plate shape. In addition to the first portion 75, the second portion 77, and the connecting portion 79, the flexible substrate 73A also has a third portion 91 and a connecting portion 93. The first portion 75 has a mounting portion 75a that connects to the photodetector 31. The second portion 77 has a rectangular shape extending along the y-direction, and an A / D converter 33 and a transmission circuit 83 are provided on its upper surface. The third portion 91 has a rectangular shape, and a connector portion 85 is provided on its lower surface. The connecting portion 93 connects the second portion 77 and the third portion 91.

[0121] The process of deforming the flexible substrate 73A and storing it in the storage container 71 in Example 2 will be described. First, regarding the process of deforming the flexible substrate 73A and storing it in the storage container 71 in Example 2... Figure 16 The flat flexible substrate 73A shown has its second portion 77 raised by bending the connecting portion 79. Next, by bending the connecting portion 93, the third portion 91 is raised so that it protrudes towards the center of the first portion 75 compared to the second portion 77. Figure 17 The image shows a flexible substrate 73A in an upright state where the second part 77 and the third part 91 are in the upright state.

[0122] After the second part 77 and the third part 91 are brought into an upright position, the second part 77 is deformed in the same manner as in Embodiment 1, by bending the two wings of the second part 77 inward. By bending the two wings of the second part 77, as shown... Figure 18 As shown, the second portion 77 is deformed into a cylindrical shape. By deforming the second portion 77 into a cylindrical shape, the flexible substrate 73A is deformed into a cylindrical body with an opening 76, where the first portion 75 is the bottom surface and the second portion 77 is the side surface. In this cylindrical body, the third portion 91 is disposed above the second portion 77, which is deformed into a cylindrical shape. Furthermore, by bending the connecting portion 93, the third portion 91 becomes a shape that protrudes from the side periphery of the flexible substrate 73A toward the center.

[0123] After deforming the flexible substrate 73A into a cylindrical shape, the light receiving probe 21, the photodetector 31, the flexible substrate 73A, and the receiving container 71 are combined to form a structure as shown in the figure. Figure 19 The light detection unit 23 shown is assembled in the same manner as in Example 1, and detailed descriptions are omitted. Thus, as... Figure 16 The structure of the flexible substrate 73A shown is the same as that of Embodiment 1, which enables the flexible substrate 73A to be deformed from its initial flat state into a cylindrical shape, and the flexible substrate 73A, which has been deformed into a compact shape, to be stored in the storage container 71.

[0124]

Example 3

[0125] Next, use Figures 20 to 22 Embodiment 3 of the present invention will be described. The flexible substrate of Embodiment 3 is marked with reference numeral 73B to distinguish it from the flexible substrate 73 of Embodiment 1, etc. Figure 20 This is a top view of the flexible substrate 73B of Embodiment 3. In its initial state, the flexible substrate 73B has an overall flat plate shape extending in one direction. Furthermore, Figure 22 This is a cross-sectional view of the photodetector unit 23. The exception is that the photodetector 31 is a cross-sectional view of a partially cut-off section.

[0126] The flexible substrate 73B of Embodiment 3 includes a first portion 75, a second portion 77, a third portion 103, a fourth portion 105, a connecting portion 79, a connecting portion 109, and a connecting portion 111. The first portion 75 has a mounting portion 75a that is connected to the photodetector 31. The second portion 77 has an A / D converter 33 on its upper surface side. The third portion 103 has a transmission circuit 83 on its upper surface side.

[0127] In embodiment 3, the first portion 75, the second portion 77, and the third portion 103 are all circular. The fourth portion 105 is rectangular and has a connector portion 85 on its upper surface. Connecting portion 79 connects the first portion 75 and the second portion 77. Connecting portion 109 connects the second portion 77 and the third portion 103. Connecting portion 111 connects the third portion 103 and the fourth portion 105.

[0128] The second portion 77 and the third portion 103, like the first portion 75, are configured with the same shape and size as the inner bottom surface of the storage container 71. By configuring them with the same shape and size as the inner bottom surface of the storage container 71, the gap between the flexible substrate 73B and the storage container 71 can be reduced when the flexible substrate 73B is deformed into a columnar shape and stored in the storage container 71. As a result, the flexible substrate 73B can be held more stably inside the storage container 71.

[0129] The process of deforming the flexible substrate 73B and storing it in the storage container 71 in Example 3 will be described. First, regarding the process of deforming the flexible substrate 73B and storing it in the storage container 71 in Example 3... Figure 20 The flat flexible substrate 73B shown is deformed by bending the connecting portion 79 so that the first portion 75 and the second portion 77 overlap in the z-direction. Next, by bending the connecting portion 109, the flexible substrate 73B is deformed so that the second portion 77 and the third portion 103 overlap in the z-direction. Finally, by bending the connecting portion 111, the fourth portion 105 is positioned above the center portion of the third portion 103.

[0130] The flexible substrate 73B is deformed by overlapping the first part 75, the second part 77, and the third part 103 in the z-direction, thereby deforming the flexible substrate 73B as a whole into a columnar shape extending in the z-direction. The structure of the flexible substrate 73B, deformed into a columnar shape by bending the various connecting parts 79-111, is as follows: Figure 21 As shown. In embodiment 3, the flexible substrate 73B is folded and deformed into a cylindrical shape by overlapping the first portion 75, the second portion 77, and the third portion 103 in the z-direction.

[0131] After deforming the flexible substrate 73B into a columnar shape, similar to Embodiment 1, the light receiving probe 21, the photodetector 31, the flexible substrate 73B, and the receiving container 71 are combined to form a structure as shown in Example 1. Figure 22 The light detection unit 23 shown. Thus, it is possible to enable... Figure 20The flexible substrate 73B shown is deformed from its initial flat state into a columnar shape, and the flexible substrate 73B, deformed into a compact shape, is housed in the storage container 71. In Embodiment 3, bending is performed at the three connecting portions 79, 109, and 111. By increasing the number of bending deformation portions, the flexible substrate 73B can be deformed into a smaller compressed shape.

[0132] <Effects of the Structure of the Implementation Method>

[0133] (Item 1) The light detection unit 23 of this embodiment includes: a light detector 31 for detecting light; a storage container 71, which is cylindrical and houses the light detector 31; and a flexible substrate 73, which carries a signal processing circuit including an A / D converter 33, which converts the light signal detected by the light detector 31 from an analog signal to a digital signal, and the flexible substrate 73 is disposed inside the storage container 71 in a bent and deformed state.

[0134] According to the light detection unit 23 described in item 1, the signal processing circuit including the A / D converter 33 is mounted on the flexible substrate 73, thus allowing the flexible substrate 73 to be bent and deformed into a smaller shape. Furthermore, by arranging the flexible substrate 73 in a bent and deformed state inside the housing container 71, both the light detector 31 and the A / D converter 33 are arranged inside the housing container 71. That is, since the light detector 31 and the A / D converter 33 can be arranged closer together, the light signal detected by the light detector 31 can be quickly converted from an analog signal to a digital signal. Therefore, the reduction in light signal intensity caused by transmitting light signals in an analog state can be avoided, enabling the light detection unit 23 to be miniaturized and improving the signal-to-noise ratio (S / N) of the light signal.

[0135] (Item 2) Furthermore, in the light detection unit 23 described in Item 1, the flexible substrate 73 includes: a first portion 75 connected to the light detector 31; a second portion 77 on which a signal processing circuit including an A / D converter 33 is mounted; and a connecting portion 79 connecting the first portion 75 and the second portion 77. The connecting portion 79 is bent in an orthogonal manner to the first portion 75 and the second portion 77, and the second portion 77 is bent and deformed, thereby deforming the flexible substrate 73 into a cylindrical shape along the inner surface of the receiving container 71.

[0136] According to the light detection unit 23 described in item 2, the connecting portion 79 that connects the first portion 75 and the second portion 77 of the flexible substrate 73 is bent, and the second portion 77 is bent and deformed, thereby enabling the flexible substrate 73 to be deformed into a cylindrical shape along the inner surface of the receiving container 71. Therefore, the flat flexible substrate 73 can be deformed into a smaller cylindrical shape. Furthermore, according to this structure, due to the restoring force of the second portion 77 attempting to return to its original shape, the flexible substrate 73 exerts a pressing force G on the inner surface of the receiving container 71. Under the action of this pressing force G, the flexible substrate 73 is held inside the receiving container 71, thus, the flexible substrate 73 can be stably held inside the receiving container 71 without the use of screws or other fasteners.

[0137] (Item 3) Furthermore, in the light detection unit 23 described in Item 1, the flexible substrate 73B includes: a first portion 75 connected to the light detector 31; a second portion 77 on which a signal processing circuit including an A / D converter 33 is mounted; and a connecting portion 79 connecting the first portion 75 and the second portion 77. The connecting portion is bent in such a way that the first portion 75 and the second portion 77 overlap, thereby deforming the flexible substrate 73B into a folded state inside the storage container 71.

[0138] According to the light detection unit 23 described in item 3, bending the connecting portion 79 that connects the first portion 75 and the second portion 77 of the flexible substrate 73B causes the first portion 75 and the second portion 77 to overlap, thus allowing the flexible substrate 73B to be deformed into a folded state inside the storage container 71. Therefore, the flat flexible substrate 73B can be deformed into a smaller shape. Consequently, the volume occupied by the flexible substrate 73B can be further reduced, and thus the light detection unit 23 can be further miniaturized.

[0139] (Item 4) Furthermore, the brain function measurement device 1 of this embodiment includes: a measurement unit 3 having a light detection unit 23 of any one of items 1 to 3 and a light irradiation unit 20 for irradiating the brain of a subject M with a measurement light L, the measurement unit 3 being mounted on the head of the subject M; and a main body unit 5 electrically connected to the measurement unit 3 and having a main control unit 9, the main control unit 9 obtaining measurement data related to the brain activity of the subject M based on the light signal digitally converted by the A / D converter 33.

[0140] According to the brain function measurement device 1 described in item 4, by making the substrate equipped with the A / D converter a flexible substrate, the substrate can be bent and deformed to be disposed inside the storage container of the light detection unit. Therefore, the light detection unit can be miniaturized, and thus, the light detection unit can be disposed on the measurement unit side mounted on the head of the subject instead of on the main unit side.

[0141] According to this structure, the measurement light L, which is irradiated from the light irradiation unit 20 and passes through the brain of the subject M, is rapidly converted into a digital signal by the A / D converter 33 after being detected by the photodetector 31 of the light detection unit 23. Therefore, the reduction in light signal intensity caused by transmitting the light signal in an analog state can be avoided, thus improving the signal-to-noise ratio (S / N) of the light signal. As a result, the accuracy of brain function measurement data can be further improved.

[0142] <Other Embodiments>

[0143] Furthermore, the embodiments disclosed herein are illustrative in all respects and not restrictive. The scope of the invention includes the claims and all modifications within the meaning and scope of their equivalents. As an example, the invention can be modified as described below.

[0144] (1) In the above embodiments, a portable computer was used as the main unit 5, but it is not limited to this. Other examples of the main unit 5 include a desktop computer or a trolley with a built-in computer.

[0145] (2) In the above embodiments or modifications, the structure of connecting the measurement unit 3 and the main unit 5 by the cable 6 and transmitting brain function measurement data from the measurement unit 3 to the main unit 5 via the cable 6 has been described as an example. However, in the brain function measurement device 1, the structure of connecting the measurement unit 3 and the main unit 5 is not limited to a wired type, and the measurement unit 3 and the main unit 5 can also be connected wirelessly.

[0146] In an embodiment of the present invention, the detection signal of the measurement light L is rapidly digitally converted in the light detection unit 23 disposed on the side of the measurement unit 3. Therefore, the digitally converted detection signal of the measurement light L can be wirelessly transmitted to the main unit 5. By wirelessly connecting the measurement unit 3 and the main unit 5, the range of motion of the subject M during brain function measurement can be expanded. Therefore, brain function activity can be measured in more diverse situations, such as during movement or long-distance travel.

[0147] (3) In Embodiment 3 described above, when the flexible substrate 73 is deformed into a columnar shape, the first portion 75, the second portion 77, and the third portion 103 overlap in a parallel manner, but are not limited thereto. That is, it could also be, as... Figure 23As shown, the first portion 75 is configured to be parallel to the inner bottom surface (here, the xy plane) of the storage container 71. On the other hand, the connecting portions 79 and 109 are bent so that the second portion 77 and the third portion 103 are inclined relative to the inner bottom surface of the storage container 71. Furthermore, the second portion 77 and the third portion 103 are not limited to having the same dimensions as the first portion 75; they may also be configured to be smaller than the first portion 75. Additionally, the second portion 77 and the third portion 103 may have different shapes than the first portion 75.

[0148] Explanation of reference numerals in the attached figures

[0149] 1. Brain function measurement device; 3. Measurement unit; 5. Main body unit; 6. Cable; 7. Probe unit; 8. Probe unit holder; 9. Main control unit; 11. Operation unit; 13. Storage unit; 15. Display unit; 17. Light output unit; 19. Light-emitting probe; 20. Light irradiation unit; 21. Light receiving probe; 23. Light detection unit; 25. Head skin; 29. ​​Brain region; 31. Photodetector; 39. Main body; 41. Holder; 43. Connecting member; 51. Base member; 53. Cover member; 57. Rotation shaft; 59. Comb-shaped member; 71. Storage container; 73. Flexible substrate; 75. First part; 77. Second part; 79. Connecting part; 83. Transmission circuit; 85. Connector part.

Claims

1. A light detection unit, wherein, This optical detection unit has the following features: A photodetector, used to detect light; A cylindrical container for housing the photodetector; as well as A flexible substrate is provided with a signal processing circuit including an A / D converter, which converts the optical signal detected by the photodetector from an analog signal into a digital signal. The flexible substrate is disposed inside the storage container in a bent and deformed state. The flexible substrate comprises: The first part is connected to the photodetector; The second part includes a signal processing circuit comprising the aforementioned A / D converter; and A connecting portion that connects the first portion and the second portion. The connecting portion is bent in an orthogonal manner with the first portion and the second portion, and the second portion is bent and deformed, thereby deforming the flexible substrate into a cylindrical shape along the inner surface of the storage container.

2. A brain function measurement device, wherein, This brain function measurement device has the following features: A measuring unit having the light detection unit as described in claim 1 and a light irradiation unit for irradiating the brain of a subject, the measuring unit being mounted on the head of the subject; as well as The main unit is electrically connected to the measurement unit and has a brain function measurement unit that obtains measurement data related to the brain activity of the subject based on the optical signal that has been digitally converted by the A / D converter.

Images