Patent Publication Number: US-2023134380-A1

Title: Living body sensor

Description:
TECHNICAL FIELD 
     The present invention relates to a living body sensor. 
     BACKGROUND ART 
     A wearable living body sensor is known that can be attached to a living body to obtain biological information such as an electrocardiographic signal over a long time. For example, a living body sensor of this type has electrodes on both longitudinal directional sides, the electrodes are affixed to a chest of a living body with the longitudinal direction aligned with a sternum, and then, the living body sensor automatically starts measuring biological information (see, for example, Patent Document 1). 
     PRIOR ART DOCUMENTS 
     Patent Documents 
     
         
         [Patent Document 1] the specification of U.S. Patent Application Publication No. 2019/0254553 
       
    
     SUMMARY OF INVENTION 
     Problem to be Solved by Invention 
     When biological information is obtained for a long time by a living body sensor attached to a living body, measurement for a long time becomes useless if the living body sensor cannot obtain biological information properly. In order to correctly obtain biological information for a long time, it is necessary that the living body sensor continues to obtain biological information without being dropped off the living body. In addition, in order to prevent the living body sensor from peeling off the living body, it is preferable that the living body sensor deforms in accordance with a deformation of a body surface of the living body caused by a body movement of the living body, and at the same time, it is preferable that discomfort felt by the living body on which the living body sensor is attached can be reduced. 
     The present invention has been devised in view of the above-described points, and the present invention has an object to provide a living body sensor that can deform in accordance with a deformation of a body surface of the living body caused by a body movement of the living body, thereby reducing discomfort felt by the living body while the living body sensor is attached to the living body. 
     Means for Solving Problem 
     A living body sensor according to an embodiment of the present invention includes a flexible substrate that includes a body section; a first pad section provided at one end in a longitudinal direction of the body section via a first constricted section and including a first electrode configured to be affixed to a living body; a second pad section provided at another end in the longitudinal direction of the body section via a second constricted section and including a second electrode configured to be affixed to the living body; an obtaining section configured to obtain biological information via the first electrode and the second electrode; a wireless communication section configured to transmit the biological information obtained by the obtaining section; a component mounting section provided at the first constricted section side of the body section; and a battery setting section provided at the second constricted section side of the body section, a battery for supplying power to the component mounting section being set at the battery setting section. The body section, the first pad section, the second pad section, the obtaining section, the wireless communication section, the component mounting section, and the battery setting section are formed integrally with the flexible substrate. 
     Advantageous Effects of Invention 
     According to the disclosed technique, it is possible to provide a living body sensor that can deform in accordance with a deformation of a body surface of a living body due to a body movement of the living body. In addition, it is possible to reduce discomfort felt by the living body while the living body sensor is attached to the living body. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG.  1    is a diagram illustrating an example of a whole configuration of a living body sensor system including a living body sensor according to an embodiment. 
         FIG.  2    is a layout diagram illustrating an example of a flexible substrate depicted in  FIG.  1   . 
         FIG.  3    is a diagram illustrating a state in which the living body sensor depicted in  FIG.  1    is affixed to a chest of a subject. 
         FIG.  4    is a state transition diagram depicting an example of a transition of a mode of operation of the living body sensor depicted in  FIG.  1   . 
     
    
    
     MODE FOR CARRYING OUT INVENTION 
     Hereinafter, embodiments of the invention will be described with reference to the drawings. In each drawing, the same components are indicated by the same reference numerals and overlapping descriptions may be omitted. 
       FIG.  1    is a diagram illustrating an example of a whole configuration of a living body sensor system including a living body sensor according to an embodiment. The living body sensor system SYS depicted in  FIG.  1    includes a living body sensor  100 , an operation checking device  310  for checking an initial operation, a personal computer (PC)  320 , a reading device  410  for reading biological information from the living body sensor  100 , and a PC  420 . The living body sensor  100  is, for example, a wearable electrocardiograph that obtains an electrocardiographic signal from a living body. The living body sensor  100  may have a function of obtaining biological information other than an electrocardiographic signal, and may have a function of obtaining plural sorts of biological information. 
     The operation checking device  310  is connected to the PC  320  via, for example, a universal serial bus (USB) interface (wired). The operation checking device  310  has a capability of wirelessly communicating with the living body sensor  100  under the control of the PC  320 . For example, the PC  320  has a function of displaying a waveform representing a time change in received biological information (e.g., an electrocardiographic waveform) on a display screen. 
     The reading device  410  is connected to the PC  420 , for example, via a USB interface (wired). The reading device  410  has a function of communicating with the living body sensor  100  via a communication cable (wired communication). 
     The living body sensor  100  includes a flexible substrate (a resin substrate)  110  and a housing  120  (depicted by a dashed line) on which various components are mounted for obtaining biological information and processing the obtained biological information. The flexible substrate  110  has a body section  121 , a constricted section  122  provided at one longitudinal directional end of the body section  121 , and a pad section  123  connected to the body section  121  via the constricted section  122 . The flexible substrate  110  also includes a constricted section  124  provided at the other longitudinal directional end of the body section  121  and a pad section  125  connected to the body section  121  via the constricted section  124 . 
     The body section  121 , the constricted section  122 , the pad section  123 , the constricted section  124 , and the pad section  125  are integrally formed. By thus integrally forming these elements of the living body sensor  100  using the flexible substrate  110 , assembly costs of the living body sensor  100  can be reduced and manufacturing costs of the living body sensor  100  can be reduced as compared to assembling a living body sensor  100  by combining separate elements. 
     The body section  121  includes a component mounting section  126  at the constricted section  122  side and a battery setting section  127 , to which a battery  200  is set, at the constricted section  124  side. An external terminal  131 , to which a connector of a communication cable to be connected to the reading device  410  is connected, is formed in the component mounting section  126 . Main components mounted on the component mounting section  126  will be described with reference to  FIG.  2   . 
     For example, a coin-type battery  200  that supplies power to the component mounting section  126  is set at the battery setting section  127 . An electrode pattern  132  is formed on the pad section  123  to be affixed to a body surface of a living body, and an electrode pattern  133  is formed on the pad section  125  to be affixed to the body surface of the living body. Hereinafter, the electrode pattern  132  is also referred to as an electrode  132 , and the electrode pattern  133  is also referred to as an electrode  133 . 
       FIG.  2    is a layout diagram illustrating an example of the flexible substrate  110  depicted in  FIG.  1   . On the component mounting section  126  of the flexible substrate  110 , an application specific integrated circuit (ASIC)  210 , a system on a chip (SoC)  220 , a flash memory  230 , a switch  240 , and light emitting diodes (LED)  250  are mounted. 
     Although being not particularly limited, the flash memory  230  is of a NAND type, for example. A LED that outputs green light and a LED that outputs red light are mounted to the component mounting section  126  as the LED  250 . Hereinafter, the LED outputting green light is also referred to as a LED(G) and the LED outputting red light is also referred to as a LED(R). 
     The living body sensor  100  includes a plate member  260  (depicted in  FIG.  2    as a frame drawn by a thick broken line), such as a stainless steel plate, on a surface (back side), included in the flexible substrate  110 , opposite to a component mounting surface (front side) on which the components such as the ASIC  210  and the SoC  220  are mounted. The plate member  260  prevents the component mounting section  126  from being warped when the flexible substrate  110  is warped due to a change in a posture of a living body to which the living body sensor  100  is affixed. Thus, it is possible to prevent a disconnection of the wiring pattern due to the flexible substrate  110  being warped, and a portion at which a terminal of an electronic component such as the ASIC  210  is soldered to a pattern on the flexible substrate  110  from being damaged. 
     The switch  240  is, for example, a depression switch that is set to an ON state when a protrusion is depressed and set to an OFF state when the protrusion is not depressed. The switch  240  is mounted at a position that is next to the constricted section  122  (at an edge of the body section  121 ) and is opposite the plate member  260 . As a result, when the switch  240  is depressed while the living body sensor  100  is attached to a living body, stress caused by the depressing is applied to an edge of the component mounting section  126 . Therefore, warping of the component mounting section  126  (the plate member  260 ) occurring due to depressing of the switch  240  can be minimized, and the wiring pattern of the component mounting section  126  can be prevented from being broken or the like. Hereinafter, a living body to which the living body sensor  100  is affixed and from which biological information is obtained by the living body sensor  100  is also referred to as a subject P. 
     The constricted section  124  is formed to be longer than the constricted section  122 . As illustrated in  FIG.  3   , the living body sensor  100  is affixed along a sternum of a subject P, while the pad section  123  is faced upward (i.e., toward the subject P neck side). At this time, the pad section  125  may be located at a lower edge of the sternum (near a stomach) of the subject P whose body height is small. However, the constricted section  124  that is long and narrow allows the constricted section  124  to be deformed in accordance with bending when the subject P bends his or her body, thereby reducing discomfort felt by the subject P to which the living body sensor  100  is attached. Also, because the constricted section  124  deforms in response to bending of the body of the subject P, it is possible to reduce a possibility that the electrodes  132  and  133  adhering to the body surface of the subject P peel off the body surface due to the bending of the body of the subject P. 
     Adhesion of electrodes  132  and  133  to a body surface of a subject P may be implemented with the use of an electrically conductive adhesive; or may be implemented with the use of a non-electrically-conductive adhesive to be applied to a part of each of the electrodes  132  and  133 . Alternatively, an electrode that is specially prepared for being affixed to a living body and is affixed to each of the electrodes  132 , and  133  may be used to affix the electrodes  132 , and  133  to the subject P with the use of an electrically conductive adhesive or a non-electrically-conductive adhesive. 
     The battery setting section  127  includes pad sections  127   a  and  127   b  and a constricted section  127   c . The pad section  127   a  is provided between the constricted section  124  and the component mounting section  126 . The pad section  127   b  is provided, in a direction orthogonal to the longitudinal direction, with respect to the pad section  127   a  (an upper direction of  FIG.  2   ) at a predetermined distance from the pad section  127   a . The constricted section  127   c  is provided between pad sections  127   a  and  127   b  to connect the pad sections  127   a  and  127   b  together. 
     The pad section  127   a  has a positive electrode pattern  134  to which a positive terminal of a battery  200  ( FIG.  1   ) is connected. The pad section  127   b  has a negative electrode pattern  135  to which a negative terminal of the battery  200  is connected. For example, the positive electrode pattern  134  has a square shape with corners chamfered, and the negative electrode pattern  135  has a circular shape corresponding to a size of a circular shape of the negative terminal of the battery  200 . For example, a diameter of the negative electrode pattern  135  is equal to a diameter of the battery  200  and is equal to a length of a diagonal of the positive electrode pattern  134 . 
     When a battery  200  is set in the living body sensor  100 , an electrically conductive adhesive, such as an adhesive tape, is attached throughout the positive and negative electrode patterns  134  and  135 . Next, for example, the positive terminal of the battery  200  is adhered to the positive electrode pattern  134 . The constricted section  127   c  is then bent so that the pad sections  127   a  and  127   b  face each other, and the negative electrode pattern  135  is adhered to the battery  200  in a manner of being coincident in position with the circular shape of the negative terminal of the battery  200 . 
     Alternatively, when a battery  200  is set in the living body sensor  100 , the negative terminal of the battery  200  is adhered to the negative electrode pattern  135  via an adhesive, in such a manner that an outer periphery of the negative terminal of the battery  200  is coincident in position with an outer periphery of the negative electrode pattern  135 . Thereafter, the constricted section  127   c  is bent so that the pad sections  127   a ,  127   b  face each other, and the positive terminal of the battery  200  is adhered to the positive electrode pattern  134  via an adhesive. The body section  121  depicted in  FIG.  1    is in a state where a battery  200  is set at the battery setting section  127  with the battery  200  sandwiched between the positive electrode pattern  134  and the negative electrode pattern  135  with the constricted section  127   c  bent. 
     Making the shape of the negative electrode pattern  135  to be the same as the shape of the negative terminal of a battery  200  prevents the negative electrode pattern  135  from being short-circuited with a side surface (the positive terminal) of the battery  200 . Further, adhering the negative electrode pattern  135  to the negative terminal of a battery  200  in a manner of being coincident in position with the circular shape of the negative terminal of the battery  200  prevents the negative terminal of the battery  200  from protruding from the periphery of the negative electrode pattern  135 . Thus, it is possible to prevent the negative electrode pattern  135  from being short-circuited with the side surface of the battery  200  even if a posture of a subject P to which the living body sensor  100  is attached changes. 
     A battery  200  is adhered to the positive electrode pattern  134  and the negative electrode pattern  135  in a surface-to-surface contact manner via an electrically conductive adhesive. This reduces contact resistance compared to a case of connecting a battery  200  to the battery setting section  127 , for example, via terminals, such as terminals of a leaf spring type. In addition, even when a subject P twists his or her body or the like, it is possible to prevent a battery  200  from being removed from the battery setting section  127 , by adhering the battery  200  to the electrodes  134  and  135  in a surface-to-surface contact manner via an electrically conductive adhesive. 
     In addition, by thus sandwiching a battery  200  by the battery setting section  127  that is integrally formed onto the flexible substrate  110  and thus setting the battery  200  to the battery setting section, a thickness of the living body sensor  100  can be reduced compared to a case where a battery holder that is a separate body with respect to the flexible substrate  110  is used. This minimizes a protruding amount of the living body sensor  100  from a body surface of a subject P when the living body sensor  100  is affixed to the subject P. As a result, discomfort felt by the subject P with the living body sensor  100  attached to the subject P can be minimized. 
     By integrally forming the living body sensor  100  using the flexible substrate  110 , the living body sensor  100  can be reduced in its weight as compared to a case where a plurality of components are brought together to form a living body sensor  100 . Therefore, discomfort felt by a subject P to which the living body sensor  100  is attached can be further reduced and a possibility of the living body sensor  100  peeling off the subject P due to gravity can be reduced. 
     The flexible substrate  110  has an antenna pattern  136  formed along the longitudinal direction of the flexible substrate  110  near one (at a lower side in  FIG.  2   ) of four sides of the rectangular component mounting section  126 . Although not depicted, one end of the antenna pattern  136  is connected to the SoC  220 . The flexible substrate  110  also has a wiring pattern  137  formed at an edge (at a lower side in  FIG.  2   ) of the body section  121  and extending from the electrode pattern  133  to near the switch  240  through the constricted section  124 . The wiring pattern  137  connects the electrode  133  to the ASIC  210 . 
     The ASIC  210  is also connected to the electrode  132 , obtains biological information from a subject P through the electrodes  132  and  133 , and outputs the obtained biological information to the SoC  220 . The ASIC  210  is an example of an obtaining section. The SoC  220  has a wireless communication section that wirelessly communicates with the operation checking device  310  and transmits the biological information received from the ASIC  210  to the operation checking device  310  during an operation checking mode, which will be described later. That is, the SoC  220  functions as a wireless communication section. The SoC  220  writes the biological information received from the ASIC  210  to the flash memory  230  during a biological information recording mode, which will be described later. 
     The operation checking mode is a mode of checking as to whether the living body sensor  100  can properly obtain biological information (whether the living body sensor  100  is properly attached to the subject P and whether the living body sensor  100  operates normally). In the operation checking mode, the SoC  220  transmits biological information received from the ASIC  210  to the operation checking device  310  depicted in  FIG.  1    via the internal wireless communication section without writing the biological information to the flash memory  230 . 
     The biological information recording mode is a mode of operation switched from the operation checking mode based on a recording start instruction input from the operation checking device  310  when it is checked in the operation checking mode that biological information can be properly obtained by the living body sensor  100 . During the biological information recording mode, the SoC  220  sequentially writes biological information obtained from the ASIC  210  to the flash memory  230 . 
     The antenna pattern  136  is formed at a wiring layer of the flexible substrate  110  at a component mounting surface side (the front side). Meanwhile, the wiring pattern  137  is formed at a wiring layer of the flexible substrate  110  at the back side. This prevents a DC current flowing through the wiring pattern  137  from flowing through the antenna pattern  136  even when, for example, the electrode pattern  133  contacts a charged object and a discharge toward the electrode pattern  133  occurs. Accordingly, the DC current flowing out due to the discharge can be prevented from flowing through the antenna pattern  136  into the SoC  220 , and thus, elements in the SoC  220  can be prevented from being electrostatically destroyed. In particular, it is possible to avoid a damage to the wireless communication section connected to the antenna pattern  136 . The ASIC  210  includes a protective device against electrostatic discharge at an area where an input circuit to which the wiring pattern  137  is connected is formed. 
     The flexible substrate  110  has a slit  128  extending toward the inside along a direction perpendicular to the longitudinal direction from an edge between the component mounting section  126  and the battery setting section  127 . By providing the slit  128 , the flexible substrate  110  can be bent at a position of the slit  128  if the flexible substrate  110  is stressed due to a change in a posture of a subject P to which the living body sensor  100  is affixed. Accordingly, the body section  121  can be warped at the position of the slit  128  in accordance with a deformation of a body surface of a subject P caused by a movement of the subject P, thereby enabling reduction of discomfort felt by the subject P with the living body sensor  100  attached to the subject P. 
       FIG.  3    is a diagram illustrating a state in which the living body sensor  100  depicted in  FIG.  1    is affixed to a chest of a subject P. For example, the living body sensor  100  is affixed to the subject P with the pad section  123  at an upper side and the pad section  125  at a lower side, with the longitudinal direction of the living body sensor  100  extending along a sternum of the subject P. That is, the living body sensor  100  is affixed to the subject P with the longer constricted section  124  at the lower side. On the back side of the body section  121  of the living body sensor  100 , an adhesive tape or an adhesive agent is provided to affix the body section  121  to a body surface of the subject P. 
     The housing  120  of the living body sensor  100 , with the body section  121  contained therein, has openings at least at positions corresponding to the electrodes  132 ,  133 . The electrodes  132 ,  133  exposed from the openings can be adhered to the subject P. The living body sensor  100  wirelessly communicates with the operation checking device  310  ( FIG.  1   ) in a state in which the living body sensor  100  has been affixed to the subject P, and the electrodes  132  and  133  have been adhered to a body surface of the subject P. The living body sensor  100  transmits biological information, such as an electrocardiographic signal obtained from the subject P, to the PC  320  (see  FIG.  1   ) via the operation checking device  310 . 
     Subsequently, based on an electrocardiographic waveform or the like displayed on a display screen of the PC  320 , a physician or the like determines that the living body sensor  100  has been affixed to a proper position. The living body sensor  100  then starts an actual measurement of biological information in response to a recording start command transmitted from the PC  320  via the operation checking device  310  based on an operation of the PC  320  performed by the physician or the like. 
     The living body sensor  100  writes biological information, which has been obtained sequentially from the subject P during the measurement, together with time information, to the flash memory  230 . When the switch  240  is depressed during the measurement, and then, the switch  240  is kept continuously in the turned-on state, the living body sensor  100  sequentially writes time information (indicating the turned-on state) corresponding to the current time to the flash memory  230 . 
     The subject P with the living body sensor  100  attached thereto depresses the switch  240  if the subject P feels ill such as a palpitation or shortness of breath. While the subject P is feeling ill, the subject P may depress the switch  240  continuously. After the measurement is completed, the reading device  410  reads biological information, such as electrocardiographic signal data, time counter information accompanied by the biological information, and time counter information indicative of turned-on states of the switch  240 , for example, from the flash memory  230  of the living body sensor  100 . 
     The reading device  410  ( FIG.  1   ) transfers various information read from the flash memory  230  to the PC  420  ( FIG.  1   ). The PC  420  that receives the various information displays biological information, such as an electrocardiographic waveform, on the display screen, and displays timings when the switch  240  has been depressed. This allows the physician or the like operating the PC  420  to determine whether abnormality is present in an electrocardiographic waveform or the like obtained when the subject P felt ill. 
     For example, a duration of the measurement is set according to a duration for which the living body sensor  100  is operable by power supply from the battery  200 . For example, the duration of the measurement may be 24 hours (1 day), but may be longer depending on the capacity of the battery  200  and the power consumption of the living body sensor  100 . 
       FIG.  4    is a state transition diagram illustrating an example of transitions of modes of operations of the living body sensor  100  depicted  FIG.  1   . For example, the state transitions depicted in  FIG.  4    are implemented when a MCU built in the SoC  220  executes a control program. The control program executed by the SoC  220  is a program for controlling the overall operation of the living body sensor  100 . 
     The living body sensor  100  transitions to an initialization mode when the battery  200  is set at the battery setting section  127  and supply of power to the living body sensor  100  is initiated. The living body sensor  100  performs initial settings of the hardware and the like in the initialization mode. After the completion of initialization, the operation mode transitions to a deep sleep mode. The deep sleep mode is a mode in which the living body sensor  100  receives an interrupt caused by the switch  240  being depressed, and wireless communication functions of communicating with the ASIC  210  and the operation checking device  310  are deactivated in the mode. 
     In the deep sleep mode, the living body sensor  100  transitions to a pairing mode when depression of the switch  240  for a long time (e.g., 2 seconds) is detected, and maintains the deep sleep mode in a case where a duration of the switch  240  being depressed is shorter than 2 seconds. In the deep sleep mode, the living body sensor  100  transitions to a data output mode when the reading device  410  is connected to the external terminal. 
     In the pairing mode, the living body sensor  100  causes the wireless communication section of the SoC  220  to perform pairing with the operation checking device  310 . When the pairing is completed, the living body sensor  100  transitions to a waiting-for-command mode. If an error occurs during the pairing, the living body sensor  100  transitions to an error processing mode and performs error processing. The living body sensor  100  causes the LED(R) to blink in a predetermined pattern (e.g., at 1 second intervals) while the living body sensor  100  is in the error processing mode. 
     In the waiting-for-command mode, the living body sensor  100  transitions to an operation checking mode when a waveform checking command is received from the PC  320  via the operation checking device  310 . If an error occurs in the waiting-for-command mode, the living body sensor  100  transitions to the error processing mode. 
     In the operation checking mode, the living body sensor  100  sends instructions to the ASIC  210  to obtain biological information, and sequentially receives biological information obtained by the ASIC  210 . The living body sensor  100  transmits the received biological information to the PC  320  via the operation checking device  310 . When receiving instructions, to stop communication, from the PC  320  via the operation checking device  310  during the operation checking mode, the living body sensor  100  causes the ASIC  210  to stop obtaining biological information, and returns to the waiting-for-command mode. If an error occurs in the operation checking mode, the living body sensor  100  transitions to the error processing mode. 
     In the operation checking mode, when a recording start command is received from the PC  320  via the operation checking device  310 , the living body sensor  100  transitions to a biological information recording mode. Upon the transition from the operation checking mode to the biological information recording mode, obtaining of biological information by the ASIC  210  continues, for example. It is noted that, when the switch  240  is depressed for a long time (for example, 10 seconds) in each of the pairing mode, the waiting-for-command mode, the operation checking mode, and the error processing mode, the operation mode returns to the deep sleep mode. 
     In the biological information recording mode, the living body sensor  100  sequentially writes biological information received from the ASIC  210  to the flash memory  230 . When the switch is depressed in the biological information recording mode, the living body sensor  100  transitions to an event recording mode and then continues to be in the event recording mode until the switch  240  comes to be in a turned-off state. In the event recording mode, the living body sensor  100  sequentially writes biological information received from the ASIC  210  and time information to the flash memory  230 . That is, operations performed in the event recording mode are a duplicate of operations performed in the biological information recording mode. 
     When a predetermined set time has elapsed (e.g., 24 hours) in the biological information recording mode, the living body sensor  100  sends instructions to the ASIC  210  to stop obtaining biological information, and transitions to a waiting-for-data-output mode. In the waiting-for-data-output mode, the living body sensor  100  waits for the reading device  410  to be connected to the external terminal  131 . When the reading device  410  has been connected to the external terminal  131 , the living body sensor  100  transitions to a data output mode. In the data output mode, the reading device  410  accesses the flash memory  230  through the external terminal  131  to read biological information, time information, and the like stored in the flash memory  230 . In each of the waiting-for-data-output mode and the data output mode, if the switch  240  is depressed for a long time (e.g., 5 seconds), the operation mode returns to the initialization mode, and initial settings are performed in the initialization mode. 
     As depicted in  FIG.  4   , an operation mode of the living body sensor  100  may be transitioned to another operation mode from among various operation modes, depending on when the switch  240  is depressed and an operation mode of the living body sensor  100  at the time when the switch  240  is depressed. Therefore, as described above, the single switch  240  can implement soft switches with which it is possible to detect a plurality of events. As a result, because only the single switch  240  is sufficient to be mounted to the living body sensor  100 , the living body sensor  100  can be miniaturized and the cost of the living body sensor  100  can be reduced. 
     As described above, in the embodiment depicted in  FIGS.  1 - 4   , each element of the living body sensor  100  can be integrally formed via the flexible substrate  110  to make the living body sensor  100  simpler in structure than a case of assembling a living body sensor  100  by combining separate components. This can reduce the manufacturing costs and the assembly costs of the living body sensor  100 . 
     By integrally forming the living body sensor  100  via the flexible substrate  110 , the living body sensor  100  affixed to a subject P can be deformed in accordance with a deformation of a body surface of the subject P caused by a movement of the subject P. Accordingly, it is possible to avoid a failure such as breaking of a wiring pattern due to warping of the flexible substrate  110 . In addition, it is possible to reduce a possibility that the electrodes  132  and  133  adhering to the subject P peel off from the body surface due to bending, thereby reducing discomfort felt by the subject P while the living body sensor  100  is attached to the subject P. 
     It is possible to prevent an electrostatic current present in the pad sections  123  and  125  from flowing into the antenna pattern  136  and damaging the antenna pattern  136 . Further, it is possible to prevent an electric current from flowing into the component mounting section  126  through the antenna pattern  136  and it is possible to avoid an electrostatic discharge damage of an electronic component such as the SoC  220  mounted on the component mounting section  126 . 
     Because the battery setting section  127  can be integrally formed with the flexible substrate  110 , the living body sensor  100  can be simplified in structure and manufacturing costs can be reduced. In addition, because a thickness of the living body sensor  100  can be thus reduced, a protruding amount of the living body sensor  100  when the living body sensor  100  is affixed to a subject P can be minimized. Further, because all the elements other than the components mounted on the component mounting section  126  can be formed by electrically conductive patterns, manufacturing costs and assembly costs can be reduced. 
     The negative electrode pattern  135  is formed to correspond to the circular shape of the negative terminal of the battery  200 . Therefore, when the negative terminal of the battery  200  is adhered to the negative electrode pattern  135  in a manner of being coincident in position with the negative electrode pattern  135 , it is possible to prevent the periphery of the negative terminal of the battery  200  from extending from the periphery of the negative electrode pattern  135 . Thus, it is possible to prevent the negative electrode pattern  135  from short-circuiting with the side wall of the battery  200  even if a posture of a subject P to which the living body sensor  100  is attached changes in any way. 
     The battery  200  is adhered to the positive electrode pattern  134  and the negative electrode pattern  135  in a surface-to-surface contact manner via a conductive adhesive. This reduces the contact resistance and prevents the battery  200  from being removed from the battery setting section  127 , as compared to a case where the battery  200  were set at the battery setting section  127  via terminals, such as terminals of leaf springs. 
     Further, by sandwiching the battery  200  by the battery setting section  127  to set it to the battery setting section  127 , that is integrally formed with the flexible substrate  110 , the thickness of the living body sensor  100  can be reduced compared to a case of using a flexible substrate  110  and a battery holder that is a separate body with respect to the flexible substrate  110 . This minimizes the protruding amount of the living body sensor  100  from a body surface of a subject P when the living body sensor  100  is attached to the subject P. As a result, discomfort felt by the subject P with the living body sensor  100  attached thereto can be minimized. 
     The slit  128  allows the body section  121  to warp around the slit  128  in accordance with a deformation of a body surface of a living body caused by a body movement while the living body sensor  100  is attached to a subject P, thereby reducing a discomfort felt by the subject P while the living body sensor  100  is attached to the subject P. It is possible to release stress applied to the body section  121  due to a deformation of a body surface of a living body as a result of a portion surrounding the slit  128  warping, and it is possible to prevent the stress from being applied to the component mounting section  126 . Accordingly, it is possible to prevent the wiring pattern or the like of the component mounting section  126  from being damaged. 
     Rigidity of the plate member  260  can reduce warping of the component mounting section  126  and prevent the wiring pattern of the component mounting section  126  from being broken. Warping of the component mounting section  126  can be reduced because stress generated when the switch  240  is depressed is applied to an edge of the component mounting section  126 . 
     Although the present invention has been described based on the embodiments, the present invention is not limited to the specifically disclosed embodiments. In these respects, modifications/changes can be made without departing from the spirit of the present invention. 
     The present application claims priority to Japanese patent application No. 2020-059654 filed Mar. 30, 2020, and the entire contents of Japanese patent application No. 2020-059654 are herein incorporated by reference. 
     DESCRIPTION OF SYMBOLS 
     
         
         
           
               100  Living body sensor 
               110  Flexible substrate 
               120  Housing 
               121  Body section 
               122  Constricted section 
               123  Pad section 
               124  Constricted section 
               125  Pad section 
               126  Component mounting section 
               127  Battery setting section 
               127   a ,  127   b  Pad sections 
               127   c  Constricted section 
               128  Slit 
               131  External terminal 
               132 ,  133  Electrode patterns 
               134  Positive electrode pattern 
               135  Negative electrode pattern 
               136  Antenna pattern 
               200  Battery 
               210  ASIC 
               220  SoC 
               230  Flash memory 
               240  Switch 
               250  LED 
               260  Plate member 
               310  Operation checking device 
               320  PC 
               410  Reading device 
               420  PC 
             P Subject 
             SYS Living body sensor system