JP4643730B2 - In vivo information acquisition device - Google Patents

Description

  The present invention relates to an in-vivo information acquisition apparatus that acquires in-vivo information and transmits the in-vivo information outside the living body.

  In recent years, in the field of endoscopes, swallowable capsule endoscopes have been proposed. This capsule endoscope is provided with an imaging function and a wireless communication function. The capsule endoscope is swallowed from the mouth of the subject for observation (examination) until it is spontaneously discharged until it is spontaneously discharged. It has a function of moving and taking images of the in-subject image at intervals of 0.5 seconds, for example.

  While moving inside the body cavity, image data captured inside the body by the capsule endoscope is sequentially transmitted to the outside by wireless communication and stored in a memory provided outside. By carrying a receiver having a wireless communication function and a memory function, the subject can freely act after swallowing the capsule endoscope and before being discharged. After the capsule endoscope is ejected, a doctor or a nurse can make a diagnosis by displaying an image of an organ on a display based on image data stored in a memory (see, for example, Patent Document 1). ).

  Many capsule endoscopes are configured to obtain driving power from a built-in power source. Further, in order to control the drive of the capsule endoscope, a reed switch that is turned on / off by an external magnetic field is provided inside the capsule endoscope, and a permanent magnetic field supply is provided in a package that houses the capsule endoscope. A configuration with a magnet has been proposed. That is, the reed switch provided in the capsule endoscope has a structure in which the reed switch is kept off in an environment where an external magnetic field of a certain strength or higher is applied and is turned on when the strength of the external magnetic field is reduced. For this reason, while the capsule endoscope is not driven in the state of being accommodated in the package, the capsule endoscope is removed from the influence of the permanent magnet by being taken out of the package and starts to be driven. By providing such a configuration, it is possible to prevent the capsule endoscope from starting driving while being accommodated in the package (see Patent Document 1).

  In addition, the power supply from the power source to the function execution means such as the imaging means is turned on / off by a toggle operation by an external control signal such as a magnetic field from a magnet, and is packaged in a package before being introduced into the subject. The power supply from the power source can be turned on and off at an arbitrary time even in a state in which the power source is turned on, and unnecessary power consumption of the power source can be suppressed, and unnecessary radio wave radiation can be suppressed. A capsule endoscope has been proposed (see Patent Document 2).

International Publication No. 01/35813 JP 2005-81005 A

  By the way, in the capsule endoscope that is turned on and off by the above-described conventional toggle operation, for example, if the magnet is continuously moved around the capsule endoscope, the phenomenon that the interval of the toggle operation is shortened occurs.

  In this case, in a circuit that requires resetting the internal circuit when the power is turned on again after the power is turned off, a magnet is installed around the capsule endoscope in order to secure the time required for resetting the internal circuit. It is necessary to take measures to prevent the toggle operation interval from being shortened, such as preventing high-speed movement.

  In general, in a capsule endoscope, the power supply that can be built is limited, and it is necessary to suppress the power consumed by the save circuit as much as possible.

  The present invention has been made in view of the above, and an object of the present invention is to provide an in-vivo information acquisition device capable of performing power supply control that can reliably perform a reset operation with low power consumption.

  In order to solve the above-described problems and achieve the object, an in-vivo information acquiring apparatus according to the present invention includes an information acquiring unit that acquires in-vivo information, a transmitting unit that transmits the in-vivo information outside the living body, Provided between a power source for supplying power to the information acquisition means and the transmission means, the information acquisition means and / or the transmission means, and the power source, the information acquisition means and / or the transmission Power supply means for supplying power from the power source to the means, external signal detection means for detecting an external control signal input from the outside, and generating a control signal according to the detection state of the external control signal; and the external A power control means for controlling a power supply state of the power supply means in response to a control signal from the signal detection means, the information acquisition means when the power supply of the power supply means is stopped, and / or And masking means for masking a control signal from the external signal detection means input to the power control means for a certain period of time exceeding a time during which the transmission means drops to a resettable voltage. To do.

  In the in-vivo information acquiring apparatus according to the present invention as set forth in the invention described above, the mask means is a pulse width extension circuit that extends the pulse width of the control signal for the predetermined period.

  In the in-vivo information acquiring apparatus according to the present invention as set forth in the invention described above, the pulse width extension circuit is a charge / discharge circuit.

  In the in-vivo information acquiring apparatus according to the present invention as set forth in the invention described above, the pulse width extension circuit is a timer.

  The in-vivo information acquiring apparatus according to the present invention may further include a discharging unit that discharges the electric charge of the capacitor connected to the power supply unit. The discharging unit may supply power to the power control unit. Discharging is started at substantially the same timing as stopping.

  The in-vivo information acquiring apparatus according to the present invention may further include a discharging unit that discharges the electric charge of the capacitor connected to the power supply unit. The discharging unit may supply power to the power control unit. The discharge is started at a timing before the start.

  In the in-vivo information acquiring apparatus according to the present invention as set forth in the invention described above, the discharging means is a semiconductor switch.

  In the in-vivo information acquiring apparatus according to the present invention as set forth in the invention described above, the discharge means is a mechanical switch.

  In the in-vivo information acquiring apparatus according to the present invention, in the above invention, the power control unit is configured to provide a power supply state and a power supply stop state of the power supply unit according to a control signal from the external signal detection unit. Is toggled.

  In the in-vivo information acquiring apparatus according to the present invention, the external control signal input from the outside is a plurality of external control signals in the above-described invention, and the external control differs depending on whether the power supply means supplies power or stops supplying power. A signal is used.

  In the in-vivo information acquiring apparatus according to the present invention as set forth in the invention described above, the external control signal is any one or a combination of a magnetic signal, an optical signal, and a radio signal.

  In the in-vivo information acquiring apparatus according to the present invention as set forth in the invention described above, the in-vivo information is any one or a combination of in-vivo image information, temperature information, pressure information, pH information, and position information. And

  In the in-vivo information acquiring apparatus according to the present invention as set forth in the invention described above, the transmitting means is a wireless communication means.

  In the in-vivo information acquiring apparatus according to the present invention as set forth in the invention described above, the transmitting means is an in-vivo communication means.

  In the in-vivo information acquiring apparatus according to the present invention, the mask means masks the control signal from the external signal detection means input to the switch control means for a certain period using a charge / discharge circuit, etc. There is an effect that it is possible to perform power supply control that can reliably perform the reset operation with electric power.

  Hereinafter, an in-vivo information acquisition apparatus which is the best mode for carrying out the present invention will be described.

(Embodiment 1)
First, the in-vivo information acquisition system according to the first embodiment of the present invention will be described. FIG. 1 is a schematic diagram showing an overall configuration of an in-vivo information acquisition system according to Embodiment 1 of the present invention. As shown in FIG. 1, the in-vivo information acquisition system according to the first embodiment is a capsule endoscope 2 that is an in-vivo information acquisition device that is introduced into a subject 1 and moves along a passage route. A receiving device 3 that receives a radio signal including in-vivo information transmitted from the capsule endoscope 2, and a display device 4 that displays the contents of in-vivo information included in the radio signal received by the receiving device 3. And a portable recording medium 5 for transferring information between the receiving device 3 and the display device 4.

  The display device 4 is for displaying an in-vivo image captured by the capsule endoscope 2 received by the receiving device 3 and displays an image based on data obtained by the portable recording medium 5. It has a configuration such as a workstation that performs. Specifically, the display device 4 may be configured to directly display an image or the like by a CRT display, a liquid crystal display, or the like, or may be configured to output an image or the like to another medium such as a printer.

  The portable recording medium 5 is detachable from the receiving device 3 and the display device 4 and has a structure capable of outputting and recording information when attached to both. Specifically, the portable recording medium 5 is attached to the receiving device 3 and stores in-vivo images while the capsule endoscope 2 is moving in the body cavity of the subject 1. Then, after the capsule endoscope 2 is discharged from the subject 1, the capsule endoscope 2 is taken out from the receiving device 3 and attached to the display device 4, and the recorded data is read out by the display device 4. When data is transferred between the receiving device 3 and the display device 4 by a portable recording medium 5 such as a compact flash (registered trademark) memory, and the receiving device 3 and the display device 4 are connected by wire. Unlike the capsule endoscope 2, the subject 1 can freely move even when the capsule endoscope 2 is moving inside the subject 1.

  The receiving antennas 6a to 6h are formed using a loop antenna, for example. Such a loop antenna is fixed at a predetermined position in the capsule endoscope 2, and is specifically disposed in the vicinity of a path along which the capsule endoscope 2 moves.

  The receiving device 3 is for performing reception processing of a radio signal received via any of the receiving antennas 6a to 6h. FIG. 2 is a block diagram illustrating a configuration of the receiving device 3. As illustrated in FIG. 2, the reception device 3 includes an antenna selection unit 9 that selects a plurality of reception antennas 6 a to 6 h that are suitable for reception of a radio signal, and a reception antenna that is selected by the antenna selection unit 9. 6 includes a receiving circuit 10 that performs processing such as demodulation on a radio signal received via 6, and a signal processing unit 11 that extracts an in-vivo image or the like from the processed radio signal. In addition, the reception device 3 corresponds to the control unit 12 that performs predetermined control regarding the output of the extracted information, the storage unit 13 that stores the extracted information, and the intensity of the radio signal output from the reception circuit 10. An A / D conversion unit 14 that performs A / D conversion of an analog signal and a power supply unit 15 that supplies driving power of each component are provided.

  The antenna selection unit 9 is for selecting an antenna suitable for receiving a radio signal from among a plurality of reception antennas 6a to 6h. Specifically, the antenna selection unit 9 selects, for example, an antenna having the highest received electric field strength based on the control of the control unit 12, and receives a radio signal received via the selected reception antenna 6 as a reception circuit 10. Has a function of outputting to.

  The receiving circuit 10 is for performing predetermined processing such as demodulation on the radio signal received via the selected receiving antenna 6. The receiving circuit 10 has a function of outputting an analog signal corresponding to the intensity of the radio signal to the A / D converter 14.

  The signal processing unit 11 is for extracting predetermined information from the signal subjected to predetermined processing by the receiving circuit 10. For example, when a wireless signal received by the receiving device 3 is transmitted from an electronic device having an imaging function, the signal processing unit 11 extracts image data from the signal output from the receiving circuit 10. .

  The control unit 12 is for performing overall control including an antenna selection operation by the antenna selection unit 9. Specifically, the control unit 12 transfers the information output from the signal processing unit 11 to the storage unit 13 for storage, and also outputs the digital signal (corresponding to the reception intensity) output from the A / D conversion unit 14. For example, the reception antenna 6 to be used is determined based on RSSI (Received Signal Strength Indicator)), and the antenna selection unit 9 is instructed.

  The storage unit 13 is for storing information extracted by the signal processing unit 11. As a specific configuration of the storage unit 13, the storage unit 13 itself may store information by providing a memory or the like. However, in the first embodiment, as will be described later, the storage unit 13 is a portable recording device. It has a function of writing information to the medium 5.

  Next, the capsule endoscope 2 will be described. The capsule endoscope 2 functions as an example of an in-vivo information acquisition device. The capsule endoscope 2 has a function of acquiring in-vivo information and transmitting a wireless signal including the acquired in-vivo information to the receiving device 3. Have.

  FIG. 3 is a block diagram schematically showing a configuration built in the exterior case member of the capsule endoscope 2. As shown in FIG. 3, the capsule endoscope 2 includes an imaging unit 33 that acquires in-vivo image information that is one of in-vivo information, an illumination unit 32 that emits illumination during imaging by the imaging unit 33, a temperature, A sensor unit 34 that detects various physical quantities such as pressure, pH, and magnetism; a wireless transmission unit 31 that generates and transmits information including in-vivo information acquired by the imaging unit 33 and the sensor unit 34; and The operation control unit 30 that controls the operation state of each unit described above, the ROM 35 that stores data such as programs and parameters used for processing control of the operation control unit 30, and the power supply that supplies power to each unit described above Part 23.

  The illumination unit 32 includes an LED 32b that outputs illumination light that irradiates the inside of the subject 1, and an LED drive circuit 32a that controls the drive state of the LED 32b. The imaging unit 33 captures at least a part of the area irradiated by the LED 32b, converts the captured image into information that can be transmitted, and transmits the information to the wireless transmission unit 31, and the CCD imaging unit 33b. And a CCD drive circuit 33a for controlling the drive state.

  The wireless transmission unit 31 generates and transmits a wireless signal including in-vivo information output from the CCD imaging unit 33b and the operation control unit 30, and the wireless signal output from the transmission circuit 31a as a radio wave. A transmission antenna 31b that outputs to the outside is provided.

  The power supply unit 23 is realized by a switch 20 having a reed switch that detects magnetism that changes depending on the proximity and separation of the external magnet 50 and switches according to the detected magnetic strength, and a button-type battery such as silver oxide. A battery 40, a power control unit 21 that controls conduction of power supplied from the battery 40 based on on / off of the switch 20, and a regulator that converts power input from the power control unit 21 into power that can be used by each unit. The power is supplied from the regulator 22 to each part in the capsule endoscope 2.

  Here, with reference to FIG. 4 and FIG. 5, the detailed structure and operation | movement of the power supply part 23 are demonstrated. In FIG. 4, as described above, the power supply unit 23 includes the battery 40, the switch 20, the power control unit 21, and the regulator 22. A power supply switch Q realized by a p-MOS transistor is connected between the battery 40 and the regulator 22, and the electric power adjusted by the regulator 22 is supplied from the operation control unit 30, the wireless transmission unit 31, the illumination unit 32, It is supplied to the imaging unit 33 and the like.

  The switch 20 includes a resistor R1 and a reed switch S1 connected in series between the positive side of the battery 40 and the ground. The resistor R1 is connected to the battery 40 side, and the reed switch S1 is connected to the ground side. Is done. Here, when the magnet 50 is brought close to the reed switch S1 in the direction A1 from the outside of the capsule endoscope 2, the reed switch S1 is closed and closed, and the magnet 50 is separated from the reed switch S1 in the direction A2. The reed switch S1 is opened to be in an open state. That is, it is a normally open switch.

  The power supply control unit 21 includes a mask signal generation unit 23, a frequency divider circuit 43, an initial state determination circuit 44, and a discharge switch Q3. The power supply control unit 21 is connected between the battery 40 and the switch 20 and the power supply switch Q, and a signal Vout output from the power supply control unit 21 is applied to the gate of the power supply switch Q so that the regulator from the battery 40 The power supply to 22 is controlled.

  The mask signal generation unit 23 forms a complementary switching circuit by the p-MOS transistor Q1 and the n-MOS transistor Q2, and each gate of the p-MOS transistor Q1 and the n-MOS transistor Q2 has a resistor R1 and A signal Vin output from a connection point with the reed switch S1 is input. The source of the p-MOS transistor Q1 is connected to the battery 40, and the drain is connected to the source of the n-MOS transistor Q2 via the resistor R. The drain of the n-MOS transistor Q2 is grounded. Further, a capacitor C is connected to the drain side of the p-MOS transistor of the resistor R, and the other end of the capacitor C is grounded. The signal Vmask output from one end side of the capacitor C is input to the inverter 41, and the inverted signal Vout1 is output.

  That is, the signal Vin, which is an on / off switching signal corresponding to the reed switch S1, is input, but when the reed switch S1 is turned off and the signal Vin is input as a power supply level, the p-MOS transistor Q1 is turned off, Since the n-MOS transistor Q2 is turned on, the electric charge accumulated in the capacitor C is gradually discharged by the time constant determined by the resistor R and the capacitor C, and the signal Vmask is output. On the other hand, when the reed switch S1 is turned on and the signal Vin is input as a ground level, the p-MOS transistor Q1 is turned on and the n-MOS transistor Q2 is turned off, so that the capacitor C is charged and the signal Vmask is Output as power level. Here, when the value of the signal Vmask becomes equal to or less than the predetermined value Vth, the inverter 41 outputs the signal Vout1 that switches from the ground level to the power supply level. When the charge / discharge of the capacitor C is repeated and the signal Vmask does not become Vth or less, a mask period in which the continuous change state of the signal Vin is not accepted is formed. In other words, the mask signal generation unit 23 is also a pulse width extension circuit that extends the pulse width of the signal Vin for a certain period.

  The signal Vout1 is input to the inverter 42, and the inverter 42 outputs the signal Vout2 obtained by inverting the input signal Vout1 to the divide-by-2 circuit 43. The divide-by-2 circuit 43 applies the signal Vout obtained by dividing the signal Vout2 by 2 to the gate of the power supply switch Q as a control on / off signal for the final power supply switch Q. Since the power supply switch Q is a p-MOS transistor, it is turned on when Vout is at the ground level.

  The conventional toggle operation is a toggle operation for turning on / off the reed switch S1, but in the first embodiment, the toggle operation for turning on / off the signal Vout1 or the signal Vout2 generated by the signal Vmask reciprocating once a predetermined value Vth. You can say that.

  The D-type flip-flop circuit 43a may be a T-type flip-flop circuit or any other circuit that can divide the frequency by two. In addition, with respect to the clear terminal CLR of the D-type flip-flop circuit 43a, an initial state determination circuit 44 in which a resistor R2 is connected to the positive side of the battery 40 and a capacitor C2 is connected to the ground side is provided. The on / off state of the power supply switch Q is determined. The resistor R1 and the capacitor C1 can be deleted when the on / off state of the power supply switch Q after the battery 40 is mounted is arbitrary.

  Here, FIG. 5 is a time chart showing an example of the on / off operation of the power supply switch Q. When the power supply switch Q is turned on to shift to the power-on state, and the high-speed movement of the magnet 50 is repeated, the signal Vmask rises sharply when Vin falls. Further, when Vin rises, the voltage gradually decreases depending on the CR time constant, but Vin falls before dropping to the predetermined value Vth, so that a voltage equal to or higher than Vth is maintained. After the pulse input of the signal Vin is lost, the values of the capacitor C and the resistor R are determined so that the CR time constant at which the signal Vmask is equal to or less than the predetermined value Vth is reached after time T3.

  On the other hand, when the power supply switch Q is turned off to shift to the power-off state, and the high-speed movement of the magnet 50 is repeated, the signal Vmask is steep when Vin falls, as in the case of power-on. stand up. Further, when Vin rises, it gradually decreases depending on the CR time constant, but the next Vin falls before dropping to the predetermined value Vth, so that a voltage equal to or higher than Vth is maintained. After the pulse input of the signal Vin is lost, the values of the capacitor C and the resistor R are determined so that the CR time constant at which the signal Vmask is equal to or less than the predetermined value Vth is reached after time T3. Here, since the capacitor C and the resistor R are shared when the power is turned on and when the power is turned off, the time T3 has the same value.

  This time T3 is a time exceeding the time T1 when the operation control unit 30 reads the operation parameter stored in the ROM 35 at the start of operation control when the power is turned on, and is provided at the output stage of the regulator 22 when the power is turned off. Further, it is necessary that the voltage of the capacitor C3 is sufficiently lowered, that is, a time exceeding the time T2 until the electric charge accumulated in the capacitor C3 is sufficiently discharged.

  By ensuring such a mask time equal to or longer than time T3, the reading time T1 can be ensured when the power is turned on, so that the reading of the operation parameter is not interrupted in the middle, and the operation control unit 30 performs normal operation. The reliability of proper operation control can be improved. Further, since the discharge time T2 is ensured when the power is turned off, for example, even when the resettable voltage of the operation control unit 30 and the resettable voltage of the ROM 35 are different, the operation control unit 30 and the ROM 35 Since the capacitor C3 is discharged so that the voltage drops to a voltage lower than the resettable voltage, malfunction due to the presence of a circuit that is not reset can be prevented.

  By the way, as described above, the capacitor C3, which is a power supply capacitor provided in the output stage of the regulator 22, starts discharging electric charges when the power is turned off. However, the capsule endoscope 2 has a leakage current when the power is turned off. Is designed to be as small as possible, the discharge time of the capacitor C3 becomes long. On the other hand, when the leakage current of the capacitor C is increased, the discharge time can be shortened. However, the battery is consumed during the storage period of the capsule endoscope 2 with the power off, and the capsule endoscope 2 is desired. The operation cannot be secured.

  For this reason, the first embodiment has a discharge switch Q3 connected to the capacitor C3 and realized by an n-MOS transistor provided between the resistor R3 having a relatively low resistance and the ground. In Q3, the signal Vout output from the divide-by-2 circuit 43 is applied to the gate. As a result, as shown in FIG. 5, when the power is turned off, the power switch Q3 is turned on, and the charge accumulated in the capacitor C3 can be discharged through the resistor R3 in a short time. It can be performed reliably and in a short time.

  In FIG. 4, all of the operation control unit 30, the wireless transmission unit 31, the illumination unit 32, and the imaging unit 33 are controlled to supply power by turning on / off the power supply switch Q. As shown in FIG. 3, a regulator 22a corresponding to the regulator 22 is further provided, the operation control unit 30 is connected to the regulator 22, and the illumination unit 32, the imaging unit 33, and the wireless transmission unit 31 are connected to the regulator 22a. The power supply switch Q may not be provided between the battery 22a and the battery 40, and only the operation control unit 30 may be controlled to supply power by turning the power supply switch Q on and off. That is, only a part of the information acquisition unit and the wireless transmission unit in the capsule endoscope 2 may be controlled to supply power.

  In addition, the power control unit 21 described above performs power supply control by turning on and off the power supply switch Q. However, the power supply switch Q is not provided, and the operation mode of the regulator 22 is directly switched as shown in FIG. Accordingly, power supply control may be performed. Specifically, as shown in FIG. 8, the power supply switch Q is deleted, and the signal Vout output from the divide-by-2 circuit 43 is output to the regulator 22, and the regulator 22 generates power based on the signal Vout. May be switched between an operation mode in which power is supplied and a sleep mode in which power is not supplied. Therefore, the power supply means corresponds to the power supply switch Q and / or the regulator 22.

  In the first embodiment, even when the power on / off toggle operation repeatedly occurs at high speed, the initial setting at the time of power on and the reset operation at the time of power off can be performed stably and reliably, and the capacitor C and Since the mask time is set by the charge / discharge circuit using the resistor R, the standby power of the power control unit 21 when the power is turned off is reduced, and power saving can be realized. Furthermore, the discharge switch Q3 can discharge the capacitor C3, which is a power supply capacitor, reliably and in a short time, and the reset operation can be performed more stably, reliably and quickly.

(Embodiment 2)
Next, a second embodiment of the present invention will be described. In the first embodiment described above, a minimum mask time is ensured by using a charge / discharge circuit including a capacitor C and a resistor R. However, in this second embodiment, a minimum is achieved by using a digital timer. A limited mask time is ensured.

  FIG. 9 is a diagram showing a detailed configuration of the power supply unit of the capsule endoscope according to the second embodiment of the present invention. FIG. 10 is an operation time chart of the power supply unit shown in FIG. 9 and 10, the power supply unit of the second embodiment is provided with a mask signal generation unit 63 instead of the mask signal generation unit 23 shown in the first embodiment. Other configurations are the same as those of the first embodiment, and the same reference numerals are given to the same components.

  The mask signal generation unit 63 includes a clock generation unit 65 and a timer 64. The clock generation unit 65 is connected to the battery 40, continuously generates a predetermined clock, and supplies it to the timer 64. The timer 64 receives a signal Vin output from a connection point between the resistor R1 and the reed switch S1, and counts time according to a clock.

  The timer 64 resets at the rising edge of the signal Vin, turns on the signal Vout1 and outputs it to the inverter 42, counts at the falling edge of the signal Vin, and turns off the signal Vout1 when the counting time exceeds the time T3. And output to the inverter 42.

  Even if such a timer is used, the same signal Vout1 as in the first embodiment can be generated, so that the same operational effects as in the first embodiment can be obtained while achieving relatively low power consumption. .

(Embodiment 3)
Next, a third embodiment of the present invention will be described. In the first and second embodiments described above, the time T1 for performing the reading process after the power is turned on is secured and the discharge time T2 is secured after the power is turned off. Then, when the power is turned on, the discharge process is first performed so that the reset state can always be secured.

  FIG. 11 is a diagram showing a detailed configuration of the power supply unit of the capsule endoscope according to the third embodiment of the present invention. FIG. 12 is a circuit diagram showing a detailed configuration of the switch control circuit shown in FIG. Further, FIG. 13 is an operation time chart of the power supply unit shown in FIG. In FIG. 11, the power supply unit of the third embodiment further includes a switch control circuit 45 in the power supply unit shown in the first embodiment. Other configurations are the same as those of the first embodiment, and the same reference numerals are given to the same components.

  The switch control circuit 45 is provided in the subsequent stage of the divide-by-2 circuit 43, and uses the signal Vout (Q output) output from the divide-by-2 circuit 43 to generate a signal Vq for controlling the power supply switch Q and a discharge switch Q3. A control signal Vq3 is generated and output. Here, as shown in FIG. 5, when the power is turned on, the switch control circuit 45 turns on the discharge switch Q3 so as to discharge before reading, and the power supply switch Q so as to perform reading after the end of the discharge. Control to turn on.

  As shown in FIGS. 12 and 13, the signal Vout (Q output) output from the divide-by-2 circuit 43 is input to the switch control circuit 45. In the switch control circuit 45, similarly to the mask signal generation unit 23, a complementary switching circuit is formed by the p-MOS transistor Q4 and the n-MOS transistor Q5, and the p-MOS transistor Q4, the n-MOS transistor Q5, A signal Vout is input to each of the gates. The source of the p-MOS transistor Q4 is connected to the battery 40, and the drain is connected to the source of the n-MOS transistor Q5 via the resistor R4. The drain of the n-MOS transistor Q5 is grounded. Further, a capacitor C5 is connected to the drain side of the p-MOS transistor of the resistor R4, and the other end of the capacitor C5 is grounded. The signal Vrc output from one end of the capacitor C4 is input to the inverter 51, and is output as a ground level when a predetermined threshold value Vtha is exceeded, and is output as a power supply level when the threshold value Vtha or less. An inverter 52 is further connected to the subsequent stage of the inverter 51, and a signal Vq for controlling the power supply switch Q is output from the inverter 52. On the other hand, the signal Vout and the signal Vq are input to the AND circuit 53, and a signal Vq3 obtained by performing an AND operation on the signal Vout and the signal Vq is output as a signal for controlling the discharge switch Q3.

  Here, the capacitor C5 and the resistor R4 are determined such that the discharge voltage determined by the time constant of the capacitor C5 and the resistor R4 becomes the threshold value Vtha when the discharge time T2 has elapsed. During the discharge time T2, the signal Vq is at the power supply level and the power supply control switch Q is turned off, the signal Vq3 is at the power supply level and the discharge switch Q3 is turned on. After this time T2, the signal Vq is at the ground level and the power control switch Q is turned on, and the signal Vq3 is at the ground level and the discharge switch Q3 is turned off. That is, during the discharge time T2 before the power supply switch Q is turned on, switch control of the power off state and the discharge state is performed to extend the transition to the power on state. Note that the discharge process is not performed when the power is turned off. This is because the discharge process is first performed when the next power-on state is entered. The time T3 in the third embodiment is a time exceeding the time obtained by adding the discharge time T2 and the read time T1.

  Note that the above-described switch control circuit 45 can be applied to the second embodiment, and is provided in the subsequent stage of the divide-by-2 circuit 43 shown in FIG. 9, and the signal Vout output from the divide-by-2 circuit 43 is used. The signal Vq and the signal Vq3 described above may be generated and output.

  In the third embodiment, since the switch control circuit 45 is provided and the capacitor C3 is discharged at the beginning when the power is turned on, the reset operation can be performed reliably.

  In the first to third embodiments described above, the combination of the magnet 50 and the reed switch S1 has been described. However, the present invention is not limited to this, and a control signal transmitted by radio such as light detection including infrared rays or electromagnetic wave detection is detected. The same applies to the case where other detection circuits are used.

  In addition, the in-vivo information described in the first to third embodiments described above includes in-vivo temperature information, pressure information, pH information, acquired by the sensor unit 34, in addition to in-vivo image information captured by the image capturing unit 33. Contains location information.

  Further, in Embodiments 1 to 3 described above, in-vivo information is wirelessly transmitted by the wireless transmission unit 31, but this is not a limitation, and means for inducing an electric field to an in-vivo electric field transmission medium is wirelessly transmitted. The in-vivo information may be transmitted to the outside of the subject 1 by bio-communication for transmitting in-vivo information to the outside via an electric field transmission medium.

  In the first to third embodiments, the discharge switch Q3 is realized by a semiconductor switch such as an n-MOS transistor. However, the present invention is not limited to this, and a mechanical switch may be used.

  In the first to third embodiments described above, the toggle operation is performed using the divide-by-2 circuit 43. However, the present invention is not limited to this, and the on / off operation of the reed switch S1 is performed by deleting the divide-by-2 circuit 43. The power supply switch Q may be turned on / off in correspondence with the above. Even in this case, the pulse width of the reed switch S1 is extended by the time T3 by the mask signal generators 23 and 63, and the reading time, the discharging time, and the like can be ensured.

  In the first to third embodiments described above, the on / off operation of the power supply switch Q is controlled by using one switch called the reed switch S1, but the present invention is not limited to this. Different switches may be used for Q on and off operations, for example, a reed switch may be used during the on operation, and a light detection switch may be used during the off operation. Alternatively, even when the same light detection switch is used, the light control signal at the time of the on operation and the light control signal at the time of the off operation may be separated from each other by using different signs. Even in these cases, a mask signal generation unit is provided, and the pulse width is extended by time T3, so that the readout time, the discharge time, and the like can be ensured.

It is a figure which shows schematic structure of the in-vivo information acquisition system containing the in-vivo information acquisition apparatus which is Embodiment 1 of this invention. It is a block diagram which shows the structure of the receiver shown in FIG. It is a block diagram which shows the structure of the capsule type endoscope shown in FIG. It is a circuit diagram which shows the detailed structure of the electric power supply part shown in FIG. 6 is an operation time chart of the power supply control unit shown in FIG. 4. It is a block diagram which shows the structure of the electric power supply system which is a modification of Embodiment 1 of this invention. It is a block diagram which shows the structure of the electric power supply part which is a modification of Embodiment 1 of this invention. It is a block diagram which shows the detailed structure of the electric power supply part shown in FIG. It is a circuit diagram which shows the detailed structure of the electric power supply part of the capsule endoscope which is Embodiment 2 of this invention. It is an operation | movement time chart of the power supply control part shown in FIG. It is a circuit diagram which shows the detailed structure of the electric power supply part of the capsule endoscope which is Embodiment 3 of this invention. FIG. 12 is a circuit diagram showing a detailed configuration of a switch control circuit shown in FIG. 11. 12 is an operation time chart of the power supply control unit illustrated in FIG. 11.

DESCRIPTION OF SYMBOLS 1 Subject 2 Capsule endoscope 3 Receiving apparatus 4 Display apparatus 5 Portable recording medium 6a-6h Receiving antenna 9 Antenna selection part 10 Receiving circuit 11 Signal processing part 12 Control part 13 Storage part 14 A / D conversion part 15 Electric power Supply unit 20 Switch 21 Power supply control unit 22 Regulator 23 Mask signal generation unit 30 Operation control unit 31 Wireless transmission unit 31a Transmission circuit 31b Transmission antenna 32 Illumination unit 32a LED drive circuit 32b LED
33 Imaging unit 33a CCD drive circuit 33b CCD imaging unit 34 Sensor unit 35 ROM
40 Battery 41, 42, 51, 52 Inverter 43 Divide-by-2 circuit 43a D-type flip-flop circuit 44 Initial state determination circuit 45 Switch control circuit 50 Magnet 53 AND circuit 64 Timer 65 Clock generator S1 Reed switch R, R1-R4 Resistance C, C2, C3, C5 Capacitor Q Power supply switch Q1, Q4 p-MOS transistor Q2, Q5 n-MOS transistor Q3 Discharge switch Vin, Vmask, Vout1, Vout2, Vout, Vouta, Vrc, Vq, Vq3 signal

Claims (14)

Information acquisition means for acquiring in vivo information;
Transmitting means for transmitting the in-vivo information outside the living body;
A power source for supplying power to the information acquisition means and the transmission means;
A power supply means provided between the information acquisition means and / or the transmission means and the power source, and supplies power of the power source to the information acquisition means and / or the transmission means;
An external signal detection means for detecting an external control signal input from the outside and generating a control signal according to the detection state of the external control signal;
Power control means for controlling the power supply state of the power supply means in response to a control signal from the external signal detection means;
Control from the external signal detection means input to the power control means for a certain time exceeding the time when the information acquisition means and / or the transmission means is reduced to a resettable voltage when the power supply of the power supply means is stopped Mask means for masking the signal;
An in-vivo information acquisition device comprising:   The in-vivo information acquiring apparatus according to claim 1, wherein the mask means is a pulse width extension circuit that extends a pulse width of the control signal for the predetermined period.   The in-vivo information acquiring apparatus according to claim 2, wherein the pulse width extension circuit is a charge / discharge circuit.   The in-vivo information acquiring apparatus according to claim 2, wherein the pulse width extension circuit is a timer. Discharging means for discharging the charge of the capacitor connected to the power supply means,
The in-vivo information acquiring apparatus according to claim 1, wherein the discharging unit starts discharging at substantially the same timing as the power control unit stops power supply. Discharging means for discharging the charge of the capacitor connected to the power supply means,
The in-vivo information acquiring apparatus according to claim 1, wherein the discharging unit starts discharging at a timing before the power control unit starts power supply.   The in-vivo information acquiring apparatus according to claim 5, wherein the discharging unit is a semiconductor switch.   The in-vivo information acquiring apparatus according to claim 5 or 6, wherein the discharging means is a mechanical switch.   The power control means toggles between a power supply state and a power supply stop state of the power supply means in accordance with a control signal from the external signal detection means. The in-vivo information acquisition apparatus described in 1. The external control signal input from the outside is plural,
The in-vivo information acquisition apparatus according to claim 1, wherein different external control signals are used when the power supply unit supplies power and when power supply is stopped.   The in-vivo information acquiring apparatus according to any one of claims 1 to 10, wherein the external control signal is any one or a combination of a magnetic signal, an optical signal, and a radio signal.   The in-vivo information according to any one of claims 1 to 11, wherein the in-vivo information is any one or a combination of in-vivo image information, temperature information, pressure information, pH information, and position information. Acquisition device.   The in-vivo information acquiring apparatus according to claim 1, wherein the transmitting unit is a wireless communication unit.   The in-vivo information acquisition apparatus according to claim 1, wherein the transmission unit is an in-vivo communication unit.

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