JP6164160B2 - Optical measuring device and optical measuring method - Google Patents

Description

  The present invention relates to an optical measurement device and an optical measurement method, and more particularly, to an optical measurement device and an optical measurement method that perform measurement with a measurement probe arranged at a predetermined interval on a subject's head.

  2. Description of the Related Art Conventionally, there has been known an optical measurement device that performs measurement using a measurement probe arranged at a predetermined interval on a subject's head (see, for example, Patent Document 1).

  Patent Document 1 discloses an optical measurement device in which a measurement probe is attached to a holder (fixed member) attached to a subject's head and optical measurement (brain function measurement) is performed by near infrared spectroscopy (NIRS). ing. The plurality of measurement probes are constituted by a light transmitting probe and a light receiving probe. Optical measurement is performed by measuring light irradiated on the head from the light transmitting probe being reflected in the head and receiving the reflected measurement light by the light receiving probe. As a result, a measurement point (measurement channel) is arranged at an intermediate position between the light transmitting probe and the light receiving probe. In this brain function measuring apparatus, a plurality of light transmitting probes and light receiving probes are arranged in a square lattice pattern at predetermined intervals on the surface of the head of a subject by a holder. As a result, a plurality of measurement points are distributed in a predetermined range.

  In optical brain function measurement, the distance between adjacent light transmitting probes and light receiving probes (distance D) is set to be constant according to the depth from the head surface to the brain surface area as the measurement site. Yes. That is, the measurement light incident from the light transmission probe is reflected from the head surface by the measurement part having a depth of approximately D / 2 and received by the light reception probe. Since the depth from the surface of the head of a person (adult) to the brain surface area, which is the measurement site, falls within a substantially constant range, the distance D is set to be constant.

International Publication No. 2011-067833

  As described above, since the distance between the measurement probes is fixed, the width of the measurement range that can be measured at once in the optical brain function measurement is determined by the number of measurement probes (measurement points). Therefore, in order to perform measurement in a wide measurement range that cannot be covered by the number of measurement probes of the apparatus, it is necessary to perform multiple measurements in different measurement ranges. In that case, since it is necessary to perform analysis of measurement data separately for each measurement, it is complicated and difficult to perform unified data analysis. As described above, since the measurement range is conventionally limited by the number of measurement probes (measurement points), there is a problem that it is possible to perform measurement in a wider range than the measurement range according to the number of measurement probes. To do. Such a problem is conspicuous in a small and portable optical measuring device in which it is difficult to secure a sufficient number of measuring probes.

  The present invention has been made to solve the above-described problems, and one object of the present invention is to provide light capable of performing measurement in a wider range than the measurement range according to the number of measurement probes. It is to provide a measurement device and an optical measurement method.

  In order to achieve the above object, the optical measurement apparatus according to the first aspect of the present invention provides a predetermined measurement at a plurality of measurement points by a plurality of measurement probes arranged at predetermined intervals on the subject's head. When measuring a range, a measurement means for performing measurement individually under the same measurement conditions for each of a plurality of partial areas obtained by dividing the measurement range so as to include an overlapping part, and measurement of each overlapping part of the plurality of partial areas Data integration means for integrating measurement data for each of a plurality of partial areas based on the data and generating a single integrated data over the entire measurement range.

  In the optical measurement device according to the first aspect of the present invention, as described above, the measurement means for performing measurement individually under the same measurement condition for each of the plurality of partial regions obtained by dividing the measurement range so as to include the overlapping portion. And data integration means for integrating the measurement data for each of the plurality of partial areas based on the measurement data of the overlapping portions of the plurality of partial areas and generating a single integrated data over the entire measurement range. Thereby, in each of the partial areas, it is possible to integrate the measurement data for each partial area measured individually based on the measurement data of the overlapped part measured under the same measurement condition at the same measurement point. As a result, single integrated data over a wider measurement range can be obtained from the measurement data for each partial region having a width that can be measured by the optical measurement device. Thereby, the measurement of the range wider than the measurement range according to the number of measurement probes can be performed. This effect is particularly effective when the present invention is applied to a small and portable type optical measurement device in which it is difficult to secure a sufficient number of measurement probes. In addition, when simply performing multiple measurements, it is necessary to perform measurement data analysis separately, whereas according to the present invention, measurement data analysis is performed using a single integrated data over a wide measurement range. It can be performed easily and uniformly over the entire measurement range.

  In the optical measurement device according to the first aspect, preferably, the data integration unit corrects the measurement data of the partial regions so that the measurement data of the overlapping portions substantially coincide with each other, thereby measuring each of the plurality of partial regions. Configured to consolidate data. If comprised in this way, the measurement data of each overlapped part of the measurement data of each partial area measured separately will be made to correspond substantially, and the measurement data of each partial area will be equivalent to the data measured simultaneously. Can be considered. As a result, even when measuring data of a plurality of partial areas is integrated, highly reliable integrated data equivalent to the case where the entire measuring range is measured at once can be obtained.

  In this case, preferably, the apparatus further includes coefficient calculation means for calculating a correction coefficient that correlates a plurality of partial areas that overlap each other in the overlapping portion based on the measurement data of the overlapping portion, and the data integration means uses the correction coefficient. Thus, the measurement data of the partial area is corrected so that the measurement data of the overlapping portions substantially coincide with each other. If comprised in this way, the correction of the measurement data of the whole partial area can be easily performed by using the correction coefficient obtained from the measurement data of the overlapping part.

  In the configuration including the coefficient calculation means, preferably, the coefficient calculation means is data obtained by multiplying the measurement data of one overlapping portion and the measurement data of the other overlapping portion by a correction coefficient among a plurality of partial regions overlapping each other. A value that minimizes the error is calculated as a correction coefficient. If comprised in this way, the measurement of an overlap part can be approximated accurately (substantially match).

  In the optical measurement device according to the first aspect described above, preferably, the overlapping portion includes a plurality of measurement points that are smaller than the number of measurement points included in the non-overlapping portion other than the overlapping portion of the partial region. By configuring in this way, the number of measurement points in the non-overlapping part can be increased compared to the overlapping part, and accordingly, measurement data of more measurement points (wider measurement range) can be obtained with a smaller number of divisions. Can do. That is, since the measurement is performed a plurality of times at the same position in the overlapping portion, the measurement range becomes wider as the number of measurement points in the non-overlapping portion increases with the same number of divisions. Therefore, it is possible to obtain integrated data in a wider measurement range as the number of measurement points in the non-overlapping portion is larger.

  In this case, preferably, the overlapping portion is set so that the number of measurement points of the overlapping portion is a predetermined ratio with respect to the number of measurement points of the non-overlapping portion. If comprised in this way, the duplication part of the width (measurement point number) according to the width (namely, the number of measurement points) of a non-overlapping part can be set. Here, as the measurement data of the overlapping portion is increased, the integrated data can be approximated to data when the entire measurement range is measured at once. On the other hand, as described above, it is possible to obtain integrated data in a wide measurement range with a smaller number of divisions as the overlapping portion is narrower. Therefore, by setting the overlapping part of the appropriate width (appropriate predetermined ratio) according to the width of the non-overlapping part, good integration that balances the reliability of the integrated data and the width of the measurement range Data can be obtained.

  In the optical measurement device according to the first aspect, preferably, the optical measurement device further includes an area setting unit that receives an input of measurement probe arrangement information for each of the plurality of partial areas, and the area setting unit receives the arrangement information of each received partial area. Based on the above, it is configured to extract the measurement points in the overlapping part of the partial areas. If comprised in this way, since the position of a measurement point is decided by arrangement | positioning of a measurement probe, the measurement point in the duplication part for integrating measurement data can be determined only by inputting the arrangement information of a measurement probe. As a result, in addition to facilitating measurement data analysis with a single integrated data, the work for obtaining a single integrated data can be simplified.

  In the optical measurement apparatus according to the first aspect described above, preferably, the measurement unit has at least the measurement data sampling interval and the measurement protocol including the task period and the rest period under the same measurement condition for each of the plurality of partial regions. It is configured to take measurements. With this configuration, the measurement data of the overlapping portions of the respective partial areas can be regarded as equivalent data, so that the reliability of the integrated data can be improved. In addition, since the sampling intervals match, measurement data can be easily integrated.

  In the optical measurement method according to the second aspect of the present invention, when measuring a predetermined measurement range at a plurality of measurement points by a plurality of measurement probes arranged to be spaced apart from each other on the subject's head, overlapping portions are measured. For each of a plurality of partial areas that are divided so that the measurement range is included, a step of performing measurement individually under the same measurement condition, and a measurement for each of the plurality of partial areas based on measurement data of each overlapping part of the plurality of partial areas Integrating the data and generating a single integrated data over the entire measurement range.

  In the optical measurement method according to the second aspect of the present invention, as described above, for each of a plurality of partial areas obtained by dividing the measurement range so as to include overlapping portions, a step of individually measuring under the same measurement condition, And integrating the measurement data for each of the plurality of partial areas based on the measurement data of the overlapping portions of the partial areas, and generating a single integrated data over the entire measurement range. Thereby, in each of the partial areas, it is possible to integrate the measurement data for each partial area measured individually based on the measurement data of the overlapped part measured under the same measurement condition at the same measurement point. As a result, it is possible to perform measurement in a wider range than the measurement range according to the number of measurement probes. Moreover, measurement data analysis can be performed easily and uniformly over the entire measurement range by a single integrated data over the entire measurement range.

  According to the present invention, as described above, it is possible to perform measurement in a wider range than the measurement range corresponding to the number of measurement probes.

It is the schematic diagram which showed the whole structure of the optical measuring device by one Embodiment of this invention. It is the typical perspective view which showed the holder used for an optical measuring device. It is the block diagram which showed the structure of the optical measurement unit of the optical measurement apparatus by one Embodiment of this invention, and a control unit. It is a functional block diagram for demonstrating the control part of an optical measuring device. It is the schematic diagram which showed an example of the measurement range, measurement probe arrangement | positioning, and measurement channel arrangement | positioning. It is the schematic diagram which showed the example of the arrangement | positioning information of one partial area | region of the measurement range of FIG. FIG. 6 is a schematic diagram illustrating an example of arrangement information of the other partial region in the measurement range of FIG. 5. It is a conceptual diagram for demonstrating the calculation method of a correction coefficient. It is the graph which showed the example of the duplication channel data before and behind correction when a correction coefficient is made into a fixed value. It is the graph which showed the example of the correction coefficient at the time of making a correction coefficient into a time change value. It is the graph which showed the example of the duplication channel data before and behind correction | amendment by the correction coefficient shown in FIG. The flowchart for demonstrating the production | generation process of the integrated data of the optical measuring device by one Embodiment of this invention.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments embodying the present invention will be described below with reference to the drawings.

  First, with reference to FIGS. 1-11, the whole structure of the optical measuring device 100 by one Embodiment of this invention is demonstrated. In the present embodiment, the optical measurement device 100 is a brain function measurement device that performs optical measurement (brain function measurement) by near infrared spectroscopy (NIRS).

  As shown in FIG. 1, the optical measurement device 100 includes an optical measurement unit 1 and a control unit 2. The optical measurement device 100 has a function of measuring the brain activity of a subject using the measurement probe 3 (light transmission probe 3a and light reception probe 3b) connected via an optical fiber.

  The light transmitting probe 3a and the light receiving probe 3b of the optical measuring device 100 are each placed at a predetermined position on the surface of the subject's head by being attached to the probe fixing holder 4 attached to the subject's head. . Then, the optical measurement device 100 irradiates the measurement light in the near infrared wavelength region from the light transmission probe 3a, and makes the measurement light reflected in the head of the subject incident on the light receiving probe 3b to detect the measurement light. Obtains the light intensity (amount of received light). Based on the intensity of the acquired measurement light, it is possible to acquire a change in the amount of hemoglobin (oxygenated hemoglobin, deoxygenated globin and total hemoglobin) associated with brain activity. Thereby, the optical measuring device 100 can acquire the change of the hemoglobin amount accompanying brain activity, ie, the change of a blood flow rate, and the activation state of oxygen metabolism non-invasively. In the optical measurement, the brain activity is measured for each measurement point constituted by the pair of the light transmitting probe 3a and the light receiving probe 3b. The measurement data is acquired as the amount of hemoglobin change relative to the rest period in the brain function measurement. The measurement channel 6 is an example of the “measurement point” in the present invention.

  As shown in FIG. 2, the holder 4 has a large number of mounting holes 4a arranged in a matrix at equal intervals D (for example, 3 cm), and one measuring probe 3 is inserted into each mounting hole 4a. And can be fixed. For this reason, the adjacent light transmitting probe 3a and light receiving probe 3b are arranged so as to be separated by a predetermined distance D. The light transmitting probe 3a and the light receiving probe 3b are arranged so as to be alternately arranged in the row and column directions with respect to the mounting holes 4a. Thereby, a measurement point (measurement channel 6, see FIG. 5) is formed between the adjacent light transmission probe 3a and light reception probe 3b. The user determines the probe arrangement in the attachment hole 4 a according to the part (frontal head, top of head, temporal region, occipital region, etc.) to be measured, and attaches the measurement probe 3 to the holder 4.

  Next, the device configuration of the optical measurement device 100 will be described in detail.

  As shown in FIG. 3, the optical measurement unit 1 is configured as a small portable unit configured to be carried by a subject. The plurality of optical measurement units 1 and the control unit 2 are wirelessly connected so that mutual communication is possible. Thereby, in the optical measurement device 100, the subject can freely move by carrying the optical measurement unit 1 without being constrained to the vicinity of the control unit 2 even during brain function measurement, and is close to everyday life. It is possible to measure brain function in the environment.

  The optical measurement unit 1 includes a light transmission probe 3 a and a light reception probe 3 b connected via an optical fiber 5. A plurality of light transmitting probes 3a and light receiving probes 3b can be connected to the optical measuring unit 1, respectively. The optical measurement unit 1 includes, for example, a total of 16 measurement probes 3 including 8 light transmission probes 3a and 8 light reception probes 3b. In each of the eight light transmitting probes 3a and the light receiving probes 3b, the maximum number of measurement channels (number of measurement points) is 23 (see FIGS. 6 and 7).

  The optical measurement unit 1 includes a light source 11, a light detection unit 12, a light source drive unit 13, an A / D converter 14, a main body control unit 15, and a communication unit 16 in a portable housing 10. And a storage unit 17.

  The light source 11 is configured to output measurement light to the light transmission probe 3 a via the optical fiber 5. The light source 11 includes a semiconductor laser, an LED, and the like, and is configured to output measurement light having a plurality of wavelengths in the near infrared wavelength region. The light detection unit 12 includes an APD (avalanche photodiode), a photomultiplier tube, and the like, and is configured to detect the measurement light incident on the light receiving probe 3b via the optical fiber 5. As a result, the light detection unit 12 outputs a received light amount signal corresponding to the detected measurement light. The light source driving unit 13 is configured to turn on and off the light source 11 in accordance with a control signal from the main body control unit 15. The A / D converter 14 is configured to convert the received light amount signal of the light detection unit 12 into a predetermined digital signal and output it to the main body control unit 15. The main body control unit 15 determines the light source 11 (light source driving unit 13) and the light source 11 according to the measurement conditions such as the set sampling period and the number of measurement channels and the measurement parameters regarding the output intensity of the measurement light and the detection sensitivity of the light detection unit 12. Operation control of the light detection unit 12 is performed.

  The main body control unit 15 is a computer composed of a CPU, a memory, and the like, and is configured to control each unit of the optical measurement unit 1 described above by executing a measurement program. Thereby, the main body control unit 15 performs control such as execution of the measurement operation and measurement data to the control unit 2 based on the obtained light reception amount signal.

  The communication unit 16 includes a wireless communication module, and the communication unit 16 is configured to be capable of wireless communication with a communication unit 24 described later of the control unit 2. The storage unit 17 includes a nonvolatile memory such as a flash memory. The storage unit 17 stores brain function measurement measurement data and the like. The optical measurement unit 1 can transmit measurement data to the control unit 2 in real time by the communication unit 16 and can record measurement data in the storage unit 17.

  Next, the control unit 2 includes a control unit 21 and an analysis unit 22 including a CPU, a storage unit 23 including an HDD, and a communication unit 24 including a wireless communication module (or an externally connected wireless communication unit). And a computer (PC). The control unit 21 and the analysis unit 22 are each configured as a functional block realized by the CPU executing a control program stored in the storage unit 23. Note that the control unit 21 and the analysis unit 22 may be configured by dedicated hardware (dedicated CPU) instead of as functional blocks. Further, the control unit 2 includes a display unit 25 including a liquid crystal display and an operation input unit 26 including a keyboard and a mouse.

  Each part of the control unit 2 is controlled by the control unit 21. The control unit 21 is configured to acquire measurement data of the optical measurement unit 1 via the communication unit 24. The analysis unit 22 performs an imaging (graphing) process on the measurement data (integrated data 23b described later) recorded in the storage unit 23, an arithmetic process for performing a statistical process, and the like.

  The storage unit 23 stores various information such as a control program 23a and measurement conditions and parameters. The storage unit 23 is configured to store integrated data 23b as a measurement result. The communication unit 24 is configured to transmit information such as measurement conditions, measurement parameters, and measurement data by mutual communication with the communication unit 16 of the optical measurement unit 1.

  Here, the relationship between the measurement channel (measurement point) and the measurement range will be described. For example, as shown in FIG. 5, when 14 light transmitting probes 3a and 13 light receiving probes 3b are used, it is possible to perform measurement in a maximum of 42 measurement channels 6 at a time. Since the distance (referred to as distance D) between the light transmitting probe 3a and the light receiving probe 3b is constant, once the number of the light transmitting probes 3a and the light receiving probes 3b is determined, the measurement range that can be measured at once on the subject's head The area (area) of the MA is also determined. That is, in the case of FIG. 5, the measurement range MA has a width corresponding to 8D horizontal × 2D vertical. In FIG. 5, the probe arrangement has 3 rows and 9 columns. However, even if the number of matrices is changed, there is no significant difference in the width of the measurement range MA.

  Therefore, for example, as shown in FIGS. 6 and 7, each of the eight light-transmitting probes 3a and the light-receiving probes 3b can constitute only 23 measurement channels 6 at the maximum. ) Cannot be measured at once. Moreover, since the measurement data is acquired as a relative hemoglobin change amount of the task period T with respect to the rest period R as shown in FIG. 8, the measurement data separately performed cannot be simply combined. Because the subject's condition changes from moment to moment, even if the measurement data (hemoglobin change amount) is the same, if the baseline (corresponding to the amount of hemoglobin in the rest period R) is changing, it cannot be treated as the same data It is.

  Therefore, in the present embodiment, the optical measuring device 100 is configured to individually perform measurement under the same measurement condition for each of a plurality of partial areas A obtained by dividing the measurement range MA. Then, the optical measurement device 100 integrates the measurement data obtained for each partial region A, and generates integrated data 23b including measurement data having a number of measurement channels larger than the number of measurement channels that can be measured at one time. It is configured. In the following, as an example of division, a case where the measurement range MA in FIG. 5 is divided into two parts, that is, the partial area A1 in FIG. 6 and the partial area A2 in FIG. 7 will be described.

  Specifically, as shown in FIG. 4, in the present embodiment, the control unit 21 causes the CPU to execute the control program 23 a stored in the storage unit 23, thereby causing the region setting unit 31, the measurement unit 32, and the coefficient calculation. The unit 33 and the data integration unit 34 are configured to function. The integrated data 23b is generated by the processing of these units. Note that the area setting unit 31, the measurement unit 32, the coefficient calculation unit 33, and the data integration unit 34 may each be configured by dedicated hardware (dedicated CPU) instead of function blocks. The region setting unit 31, the measurement unit 32, the coefficient calculation unit 33, and the data integration unit 34 are respectively “area setting unit”, “measurement unit”, “coefficient calculation unit”, and “data integration unit” of the present invention. Is an example.

  As shown in FIGS. 6 and 7, the region setting unit 31 is configured to accept input of the arrangement information 41 of the measurement probes 3 for each of the plurality of partial regions A. The region setting unit 31 accepts input of the arrangement information 41 by a user input operation via the operation input unit 26 (see FIG. 3) or reading information from the storage unit 23. Specifically, the area setting unit 31 acquires the arrangement information 41 of each measurement probe 3 in the partial area A1 obtained by dividing the measurement range MA and the arrangement information 41 of each measurement probe 3 in the partial area A2. It is configured. The arrangement information itself of the final measurement range MA (see FIG. 5) is set in the control unit 21 as a measurement condition. Thereby, the area setting unit 31 acquires the arrangement information 41 indicating what kind of probe arrangement the partial area A1 and the partial area A2 are divided in the set measurement range MA.

  Each partial region A is set by the user so as to include an overlapping portion B1 with an adjacent partial region A and a non-overlapping portion B2 that does not overlap with another partial region A. In the partial region A1 of FIG. 6, the measurement channels 6 of 1ch to 19ch are included in the non-overlapping portion B2, and the measurement channels 6 of 20ch to 23ch are included in the overlapping portion B1. In the partial region A2 of FIG. 7, the measurement channels 6 of 5ch to 23ch are included in the non-overlapping portion B2, and the measurement channels 6 of 1ch to 4ch are included in the overlapping portion B1.

  The partial area A (A1, A2) is set to a size (number of measurement channels) that can be measured at once by the optical measurement unit 1. The overlapping part B1 is set so as to include a plurality of measurement channels 6 (referred to as overlapping channels C) which is smaller than the number of measurement channels included in the non-overlapping part B2. The overlapping portion B1 is set so that the number of measurement channels of the overlapping portion B1 is a predetermined ratio with respect to the number of measurement channels of the non-overlapping portion B2. That is, the width (number of measurement channels) of the overlapping portion B1 is set to be a width corresponding to the width (number of measurement channels) of the non-overlapping portion B2. 5 to 7, the number of the overlapping channel C is shown by surrounding characters. In the example shown in FIGS. 6 and 7, the number of measurement channels in the overlapping portion B1 is 4, and the number of measurement channels in the non-overlapping portion B2 is 19, for a total of 23 channels.

  Regarding the ratio of the number of measurement channels, it is preferable that the ratio of the number of measurement channels of the overlapping portion B1 to the number of measurement channels of the non-overlapping portion B2 is 1/9 or more. As will be described later, as the number of measurement channels of the overlapping portion B1 increases, the accuracy of correction of measurement data can be improved. On the other hand, the range covered by each partial region A becomes narrower and has the same number of divisions. The measurement range MA becomes narrower. Therefore, in order to achieve both the correction accuracy of the measurement data and the wide measurement range MA, it is preferable that the ratio of the number of measurement channels of the overlapping portion B1 is close to 1/9 while ensuring 1/9 or more. Note that the minimum number of divisions of the measurement range MA is two. Therefore, considering the number of measurement probes 3 of the optical measurement unit 1 (the maximum number of measurement channels in the partial area A), it is possible to sufficiently secure the number of measurement channels in the overlapping portion B1 even when the desired measurement range MA is divided into two. In this case, this ratio may be larger than 1/9. As a result, the ratio of the number of measurement channels of the overlapping portion B1 in the example shown in FIGS. 6 and 7 is 4/19 = 1 / 4.75. When the measurement range MA is divided into two and the ratio of the number of measurement channels of the overlapping portion B1 is less than 1/9, or when the measurement range MA cannot be covered by the two divisions, the ratio of the number of measurement channels of the overlapping portion B1 is calculated. What is necessary is just to examine the division | segmentation number which can be 1/9 or more.

  The region setting unit 31 is configured to extract the measurement channel 6 in the overlapping portion B1 between the partial regions A based on the received arrangement information 41 of each partial region A. That is, the area setting unit 31 compares the arrangement of the measurement probes 3 in the adjacent partial area A1 and the arrangement of the measurement probes 3 in the partial area A2, and extracts the measurement channels 6 that overlap each other as the overlapping channel C. To do.

  As shown in FIG. 4, when measuring the entire measurement range MA, the measurement unit 32 individually performs measurement under the same measurement condition for each of a plurality of partial areas A obtained by dividing the measurement range MA so as to include the overlapping portion B1. Configured to do. Specifically, the measurement unit 32 is configured to perform measurement for each of the plurality of partial areas A under the same measurement conditions as at least the measurement data sampling interval and the measurement protocol including the task period and the rest period. ing.

  The measurement protocol includes the length of the task period T (seconds), the length of the rest period R (seconds), the number of iterations between the task and rest, the task content, and the like. By making these measurement conditions the same, the measurement data obtained in each partial area A can be regarded as substantially equivalent data. The measurement unit 32 controls the operation of the light source 11 (light source driving unit 13) and the light detection unit 12 according to the measurement conditions, thereby measuring the measurement data of each measurement channel 6 (including the overlapping channel C) included in the partial region A. get. The measurement unit 32 obtains measurement data of individual partial areas A over the entire measurement range MA by performing the number of times corresponding to the number of partial areas A (the number of divisions of the measurement range MA).

  As shown in FIG. 4, the coefficient calculation unit 33 calculates a correction coefficient K that correlates a plurality of partial areas A that overlap each other in the overlapping part B1, based on the measurement data of the overlapping channel C included in the overlapping part B1. Is configured to do. The correction coefficient K is a correction multiplier of the measurement data of the other partial area A (A2) with respect to the measurement data of one partial area A (A1) when overlapping (adjacent) partial areas A are integrated. The coefficient calculation unit 33 minimizes the error between the measurement data of one overlapping portion B1 and the data obtained by multiplying the measurement data of the other overlapping portion B1 by the correction coefficient K among the plurality of partial regions A overlapping each other. The value is configured to be calculated as the correction coefficient K.

  For example, in the example of FIGS. 6 and 7, the coefficient calculation unit 33 measures the measurement data of the overlapping channel C (20 ch to 24 ch) of one partial region A1 and the overlapping channel C (1 ch to 4 ch) of the other partial region A2. The correction coefficient K is calculated based on the measured data. First, as shown in FIG. 8, the coefficient calculation unit 33 calculates and averages the measurement data of the four overlapping channels C (20ch to 24ch) in the partial area A1 and calculates the overlapping channel data 42a in the partial area A1. In addition, the coefficient calculation unit 33 calculates and averages the measurement data of the four overlapping channels C (1ch to 4ch) in the partial area A2 to calculate the overlapping channel data 42b in the partial area A2. The coefficient calculation unit 33 calculates the correction coefficient K based on the overlapping channel data 42a (referred to as function F) of the partial area A1 and the overlapping channel data 42b (referred to as function G) of the partial area A2.

  As the correction coefficient K, a constant value can be adopted as the correction coefficient K in all sections (total measurement time) of measurement data. Further, the correction coefficient K may be a value (a function of time) that changes according to the measurement time.

  When the correction coefficient K is set to a constant value, the coefficient calculation unit 33, in a predetermined section (predetermined time interval), data (K × G) obtained by multiplying the overlapping channel data 42b by the correction coefficient K and the overlapping channel data 42a. The value of the correction coefficient K (K≈F / G) is determined so that the error (difference) from (F) is minimized. Specifically, the predetermined section is a task period T. The correction coefficient K is calculated by a statistical method such as a least square method. FIG. 9 shows an example of overlapping channel data 42a (F), overlapping channel data 42b (G) before correction, and overlapping channel data 42b (K × G) after correction.

  When the correction coefficient K is a time function, the coefficient calculation unit 33 overlaps with a moving average Fm (t) of an arbitrary time window (a part of a predetermined time portion is cut from all waveforms) of the overlapping channel data 42a. A moving average Gm (t) of an arbitrary time window of the channel data 42b is obtained. Then, the coefficient calculation unit 33 obtains a correction coefficient K (t) such that K (t) ≈Fm (t) / Gm (t). The range of the time window is a predetermined time value (sec) or the number of data points (2048 points, etc.). FIG. 10 shows an example of the calculated correction coefficient K (t). FIG. 11 shows an example of overlapping channel data 42a (F), overlapping channel data 42b (G) before correction, and overlapping channel data 42b (K (t) × G) after correction.

  As shown in FIG. 4, the data integration unit 34 integrates the measurement data for each of the plurality of partial areas A based on the measurement data of the overlapping portions B1 (overlapping channels C) of the plurality of partial areas A, and determines the measurement range. It is configured to generate a single integrated data 23b over the entire MA. In addition, the data integration unit 34 corrects the measurement data of the partial area A so that the measurement data of the overlapping part B1 (overlapping channel C) are substantially identical (approximated) to each other, thereby measuring each of the plurality of partial areas A. Configured to consolidate data.

  The data integration unit 34 multiplies the measurement data of the partial area A (A2) measured later by the correction coefficient K so as to match the measurement data of the partial area A (A1) measured first. Thus, the integrated data 23b is generated. The data integration unit 34 is configured to integrate the addition average of the measurement data of the partial areas A as the measurement data of the overlap channel C for the overlap portion B1 (overlap channel C).

When integrating the measurement data of the partial area A1 of FIG. 6 and the partial area A2 of FIG. 7 to generate the integrated data 23b of the measurement range MA of FIG. 5, the data integration unit 34 performs the integrated data 23b as follows. Is generated. In the following, the data of Xch (X = 1 to 42) of the integrated data 23b is Ps (X), the measurement data of Ych (Y = 1 to 23) of the partial area A1 is P1 (Y), and Zch ( The measurement data of Z = 1 to 23) is expressed as P2 (Z).
1: For 1ch to 19ch of the integrated data 23b, Ps (X) = P1 (Y). Here, X = Y = 1-19.
2: In the integrated data 23b 20ch to 23ch, Ps (X) = (P1 (Y) + K × P2 (Z)) / 2. Here, Y = 20-23 and Z = 1-4.
3: For 24ch to 42ch of the integrated data 23b, Ps (X)) = K × P2 (Z). Here, Z = 5-23.

  For example, the 22ch data Ps (22) of the integrated data 23b is (P1 (22) + K × P2 (3)) / 2. As described above, the data integration unit 34 collects each measurement data (1ch to 42ch) over the entire measurement range MA and generates a single integrated data 23b. The data integration unit 34 stores the generated integration data 23b in the storage unit 23 as a single measurement data file.

  Here, since the measurement data of the partial area A1 and the measurement data of the partial area A2 are acquired separately, there is always a variation factor between the respective measurement data. However, when each measurement is performed on the same subject under the same measurement conditions, the time interval between the measurement of the first partial area A1 and the measurement of the second partial area A2 is also measured. It can be a relatively short time to change the arrangement of the probes 3. Therefore, by correcting the overlapping channel data 42b with the correction coefficient K and substantially matching the overlapping channel data 42a, it is possible to regard these measurement data as equivalent data. By correcting the measurement data P2 (Z) of the partial area A2 with the correction coefficient K obtained as a result, the measurement data P1 (Y) of the partial area A1 and the measurement data P2 of the partial area A2 included in the integrated data 23b. (Z) can be handled (integrated) as equivalent data within the accuracy range required in practice. As a result, measurement data of a wide measurement range MA that cannot be measured at once by the measurement probe 3 provided in the optical measurement unit 1 can be handled and analyzed in a unified manner as the integrated data 23b.

  Next, with reference to FIG. 4, FIG. 6 to FIG. 8, and FIG. 12, the generation processing of the integrated data 23b by the optical measurement device 100 of the present embodiment will be described. The following control processing is executed by the control unit 21 (region setting unit 31, measurement unit 32, coefficient calculation unit 33, and data integration unit 34) of the optical measurement device 100 (see FIG. 4).

  First, in step S1 of FIG. 12, the measurement program of the control unit 21 is activated. In step S2, the control unit 21 sets measurement conditions and measurement parameters. The control unit 21 acquires measurement conditions and measurement parameters by a user input operation via the operation input unit 26 or reading information from the storage unit 23. The control unit 21 sends measurement parameters related to the sampling period and measurement protocol, the measurement conditions such as the number of measurement channels (measurement range MA), the output intensity of the measurement light and the detection sensitivity of the light detection unit 12 via the communication unit 24. To the optical measurement unit 1.

  In step S <b> 3, the region setting unit 31 sets divisional arrangement conditions for the measurement probe 3. In other words, the region setting unit 31 receives the user's input operation via the operation input unit 26 (see FIG. 4) or reads information from the storage unit 23, and the arrangement information 41 of the measurement probe 3 for each partial region A (see FIG. 6 and FIG. 6). (See FIG. 7). As a result, the number of divisions of the measurement range MA (number of partial areas A) and the number and arrangement of measurement channels 6 for each partial area A are determined.

  In step S4, the region setting unit 31 compares the arrangement information 41 for each partial region A, and extracts an overlapping portion B1 (overlapping channel C). In the example of FIGS. 6 and 7, the region setting unit 31 automatically extracts 20 ch to 24 ch of the partial region A1 and 1 ch to 4 ch of the partial region A2 as overlapping channels C.

  In step S5, the measurement unit 32 determines whether a measurement start instruction has been accepted. When a measurement start instruction is received by a user input operation via the operation input unit 26, the process proceeds to step S6. When it is determined that the measurement start instruction has not been received, the measurement unit 32 stands by by repeating the determination in step S5. At this time, the user inputs the measurement start instruction after attaching the measurement probe 3 to the holder 4 and realizing the arrangement set as the arrangement information of the partial area A1.

  When the measurement start instruction is accepted, the measurement unit 32 transmits a measurement start instruction to the optical measurement unit 1 in step S6. Thereby, the optical measurement unit 1 performs measurement according to the measurement conditions set in step S <b> 2 and transmits the obtained measurement data to the control unit 2. The measurement unit 32 stores the measurement data acquired via the communication unit 24 in the storage unit 23 as the measurement data of the partial area A1.

  In step S7, the measurement unit 32 determines whether or not to end the measurement. The measurement unit 32 determines the end of measurement based on a user input operation (operation for ending measurement) via the operation input unit 26 or a predetermined time elapsed in advance. Until it is determined to end the measurement, the measurement is continued and the determination in step S7 is repeated. If it is determined that the measurement is to be terminated, the measurement unit 32 transmits a measurement termination instruction to the optical measurement unit 1 in step S8. As a result, the first measurement (partial area A1) is completed.

  In step S9, the measurement unit 32 determines whether or not the measurement for the number of divisions has been completed. That is, the measuring unit 32 determines whether or not the measurement for all the partial areas A has been completed. If the measurement has not been completed, the process returns to step S5, and the measurement unit 32 starts measuring the next (second) partial area A2. In step S5, the user changes the arrangement of the measurement probe 3 in the holder 4 and realizes the arrangement set as the arrangement information of the partial area A2, and then inputs a measurement start instruction. By repeating the processes of steps S5 to S9, the measurement unit 32 individually acquires measurement data under the same measurement condition for each partial region A. When the measurement unit 32 determines in step S9 that the measurement for the number of divisions has been completed, the process proceeds to step S10.

  In step S10, the coefficient calculation unit 33 calculates the correction coefficient K based on the measurement data of the overlapping portion B1 (overlapping channel C). That is, as shown in FIG. 8, the coefficient calculation unit 33 calculates the overlapping channel data 42a of the partial area A1 and the overlapping channel data 42b of the partial area A2. Then, the coefficient calculator 33 determines the value of the correction coefficient K based on the overlapping channel data 42a and the overlapping channel data 42b.

  In step S <b> 11 of FIG. 12, the data integration unit 34 corrects the measurement data of the partial area A using the correction coefficient K, and integrates the measurement data for each of the partial areas A. The data integration unit 34 corrects the measurement data of the partial area A measured after the second time by multiplying by the correction coefficient K. Further, the data integration unit 34 integrates the addition average of the measurement data of the partial areas A as the measurement data of the overlap channel C for the overlap portion B1 (overlap channel C). Thereby, the single integrated data 23b over the whole measurement range MA (42ch) is produced | generated from the measurement data (each 23ch) for every partial area A. FIG. In step S <b> 12, the data integration unit 34 stores the generated integrated data 23 b in the storage unit 23.

  Thus, the generation process of the integrated data 23b by the optical measurement device 100 is completed. As a result, the user can perform a unified analysis process on the single integrated data 23b when the analysis unit 22 of the control unit 2 analyzes the data.

  In the present embodiment, the following effects can be obtained.

  In the present embodiment, as described above, for each of the plurality of partial areas A obtained by dividing the measurement range MA so as to include the overlapping portion B1, the measurement unit 32 for performing measurement individually under the same measurement condition, A data integration unit 34 is provided that integrates the measurement data for each of the plurality of partial areas A based on the measurement data of the overlapping portions B1 of the partial areas A, and generates a single integrated data 23b over the entire measurement range MA. Thereby, in each partial area A, based on the measurement data of the overlapping part B1 measured under the same measurement condition for the same measurement channel 6, the measurement data for each partial area A can be integrated. As a result, single integrated data 23b over the wider measurement range MA can be obtained from the measurement data for each partial area A having a size that can be measured by the optical measurement device. Thereby, the measurement of the range wider than measurement range MA according to the number of measurement probes 3 can be performed. This effect is particularly effective in the optical measurement device 100 including the small and portable optical measurement unit 1 in which it is difficult to secure a sufficient number of measurement probes 3. In addition, when simply performing a plurality of measurements, it is necessary to perform measurement data analysis separately, whereas according to the optical measurement device 100 of the present embodiment, a single integration over the entire wide measurement range MA. The data 23b makes it possible to perform measurement data analysis easily and uniformly over the entire measurement range MA.

  In the present embodiment, as described above, the measurement data for each of the plurality of partial areas A is integrated by correcting the measurement data for the partial area A so that the measurement data of the overlapping portion B1 substantially match each other. Thus, the data integration unit 34 is configured. Thereby, it becomes possible to regard the measurement data of each partial area A as the same data as when measured simultaneously. As a result, even when measuring data of a plurality of partial areas A are integrated, it is possible to obtain highly reliable integrated data 23b equivalent to the case where the entire measuring range MA is measured at once.

  In the present embodiment, as described above, the coefficient calculation unit 33 that calculates the correction coefficient K that associates the plurality of partial areas A that overlap each other in the overlapping part B1 is provided based on the measurement data of the overlapping part B1. Then, the data integration unit 34 is configured to correct the measurement data of the partial region A using the correction coefficient K so that the measurement data of the overlapping portion B1 substantially match each other. Accordingly, the measurement data of the entire partial area A can be easily corrected by using the correction coefficient K obtained from the measurement data of the overlapping portion B1.

  In the present embodiment, as described above, among the plurality of partial areas A that overlap each other, the measurement data of one overlapping portion B1, and the data obtained by multiplying the measurement data of the other overlapping portion B1 by the correction coefficient K The coefficient calculation unit 33 is configured to calculate a value that minimizes the error as the correction coefficient K. Thereby, the measurement of the overlapping part B1 can be approximated (substantially matched) with high accuracy.

  Further, in the present embodiment, as described above, a plurality of measurement channels 6 (overlap channel C) having a smaller number than the number of measurement channels included in the non-overlap portion B2 other than the overlap portion B1 of the partial region A are overlapped portions. Include in B1. Thereby, as the number of measurement channels of the non-overlapping portion B2 increases, measurement data of more measurement channels 6 (wider measurement range MA) can be obtained with a smaller number of divisions.

  Further, in the present embodiment, as described above, the overlapping portion B1 is set so that the number of measurement channels of the overlapping portion B1 is a predetermined ratio with respect to the number of measurement channels of the non-overlapping portion B2. Thereby, the overlapping part B1 having a width (number of measurement channels) corresponding to the width of the non-overlapping part B2 (that is, the number of measurement channels) can be set. Here, as the measurement data of the overlapping portion B1 is increased, the integrated data 23b can be approximated to data when the entire measurement range MA is measured at once. Therefore, by setting the overlapping portion B1 having an appropriate width (appropriate predetermined ratio) according to the width of the non-overlapping portion B2, it is possible to balance the reliability of the integrated data 23b and the width of the measurement range MA. It is possible to obtain excellent integrated data 23b.

  Moreover, in this embodiment, the area | region setting part 31 which receives the input of the arrangement | positioning information 41 of the measurement probe 3 for every some partial area | region A is provided as mentioned above. Then, the region setting unit 31 is configured to extract the measurement channel 6 in the overlapping portion B1 between the partial regions A based on the received arrangement information 41 of each partial region A. Thereby, the measurement channel 6 (overlapping channel C) in the overlapping part B1 can be determined only by inputting the arrangement information 41 of the measuring probe 3. As a result, the work for obtaining the single integrated data 23b can be simplified.

  In the present embodiment, as described above, the measurement data sampling interval and the measurement protocol including the task period T and the rest period R are measured under the same measurement condition so that the measurement is performed for each of the plurality of partial areas A. The measuring unit 32 is configured. Thereby, since the measurement data of the overlapping part B1 of each partial area A can be regarded as equivalent data, the reliability of the integrated data 23b can be improved. In addition, since the sampling intervals match, measurement data can be easily integrated.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiment but by the scope of claims for patent, and further includes all modifications (modifications) within the meaning and scope equivalent to the scope of claims for patent.

  For example, in the above-described embodiment, an example of the optical measurement device including the portable optical measurement unit 1 and the control unit 2 has been described, but the present invention is not limited to this. In the present invention, the present invention may be applied to a large-sized optical measurement device in which an optical measurement unit and a control unit are built in a housing.

  In addition, the measurement range MA, the arrangement of the measurement probes 3, the number of measurement channels 6, and the number of overlapping channels C shown in the above embodiment are merely examples. The measurement ranges MA, the arrangement of the measurement probes 3, the number of measurement channels 6, and the number of overlapping channels C may be configurations other than those described above.

  In the above embodiment, an example in which the measurement range MA is divided into two parts, that is, the partial area A1 and the partial area A2, is shown, but the present invention is not limited to this. In the present invention, any number of measurement ranges may be divided.

  Moreover, although the example of the structure which calculates the correction coefficient K by the coefficient calculation part was shown in the said embodiment, this invention is not limited to this. In the present invention, the data for each partial region may be corrected without calculating the correction coefficient. In the present invention, based on the measurement data of the overlapping channels for each partial area, any correction is possible as long as each measurement data of the partial area is corrected so as to substantially match the measurement data of the overlapping channels. A method may be used. For example, the measurement data may be corrected using a statistical method called independent component analysis ICA or principal component analysis PCA.

  Moreover, in the said embodiment, about the data of the overlapping part B1 (overlapping channel C) among the integrated data 23b, the value which multiplied the correction coefficient K about the measurement data (partial area A2) of mutual partial area A1 and A2. )), The present invention is not limited to this. For the overlapping portion, the measurement data of the partial area A1 may be used as it is, or a value obtained by multiplying the measurement data of the partial area A2 by a correction coefficient may be used.

  Further, in the above-described embodiment, for the sake of convenience of explanation, the description has been given using the flow-driven flowchart in which processing is performed in order along the control processing flow, but the present invention is not limited to this. In the present invention, event-driven (event-driven) processing that executes processing in units of events may be performed. In this case, it may be performed by a complete event drive type or a combination of event drive and flow drive.

3 Measurement probe 6 Measurement channel (measurement point)
23b Integrated data 31 area setting part (area setting means)
32 Measuring unit (measuring means)
33 Coefficient calculation unit (coefficient calculation means)
34 Data Integration Department (Data Integration Method)
41 Arrangement information 100 Optical measuring devices A, A1, A2 Partial area B1 Non-overlapping part B2 Overlapping part C Overlapping channel (measurement point in overlapping part)
K Correction factor MA Measurement range R Rest period T Task period

Claims (9)

When measuring a predetermined measurement range at a plurality of measurement points by a plurality of measurement probes arranged so as to be spaced apart from each other on the subject's head, a plurality of partial regions obtained by dividing the measurement range so as to include overlapping portions A measuring means for individually measuring under the same measuring conditions,
Data integration means for integrating the measurement data for each of the plurality of partial areas based on the measurement data of the overlapping portions of the plurality of partial areas, and generating single integrated data over the entire measurement range, Optical measuring device.   The data integration unit is configured to integrate the measurement data for each of the plurality of partial areas by correcting the measurement data of the partial areas so that the measurement data of the overlapping portions substantially match each other. The optical measuring device according to claim 1. Based on the measurement data of the overlapping part, further comprising a coefficient calculating means for calculating a correction coefficient for associating a plurality of the partial areas that overlap each other in the overlapping part,
3. The optical measurement according to claim 2, wherein the data integration unit is configured to correct the measurement data of the partial region using the correction coefficient so that the measurement data of the overlapping portion substantially match each other. apparatus.   The coefficient calculating means minimizes an error between the measurement data of one of the overlapping portions of the plurality of partial regions overlapping each other and the data obtained by multiplying the measurement data of the other overlapping portion by the correction coefficient. The optical measurement device according to claim 3, wherein a value is calculated as the correction coefficient.   The light according to any one of claims 1 to 4, wherein the overlapping portion includes a plurality of measurement points that are smaller in number than the number of measurement points included in a non-overlapping portion other than the overlapping portion of the partial region. Measuring device.   The optical measurement device according to claim 5, wherein the overlapping portion is set such that the number of measurement points of the overlapping portion is a predetermined ratio with respect to the number of measurement points of the non-overlapping portion. A region setting means for receiving input of arrangement information of the measurement probe for each of the plurality of partial regions;
The said area | region setting means is comprised so that the said measurement point in the said overlapping part of the said partial areas may be extracted based on the said arrangement | positioning information of each said partial area received. The optical measuring device according to claim 1.   The measurement unit is configured to perform measurement for each of the plurality of partial regions under the same measurement condition as at least a measurement data sampling interval and a measurement protocol including a task period and a rest period. The optical measurement device according to any one of 1 to 7. When measuring a predetermined measurement range at a plurality of measurement points by a plurality of measurement probes arranged so as to be spaced apart from each other on the subject's head, a plurality of partial regions obtained by dividing the measurement range so as to include overlapping portions Each step of measuring individually under the same measurement conditions;
Integrating the measurement data for each of the plurality of partial regions based on the measurement data of the overlapping portions of each of the plurality of partial regions, and generating a single integrated data over the entire measurement range. Method.

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