Position Detecting Apparatus, Body-Insertable Apparatus System, and Position Detecting Same

• US 20070255087A1
• Filed: 09/13/2005
• Published: 11/01/2007
• Est. Priority Date: 09/13/2004
• Status: Active Grant

• Current Assignee: Olympus Corporation
• Original Assignee: Olympus Corporation
• Inventors: Minai, Tetsuo
• Granted Patent: US 7,686,757 B2
• Time in Patent Office: Days
• US Class Current: 600/12
• CPC Class Codes: A61B 1/041 Capsule endoscopes for imaging
• CPC Class Codes: A61B 5/062 using magnetic field

Abstract

A position detecting apparatus 3 includes receiving antennas 7a to 7d to receive a radio signal, transmitting antennas 8a to 8d to transmit a radio signal for power supply to a capsule endoscope 2, a first linear magnetic field generator 9 that generates a first linear magnetic field, a second linear magnetic field generator 10 that generates a second linear magnetic field, a diffuse magnetic field generator 11 that generates a diffuse magnetic field, a processing device 12 that performs a predetermined process on the radio signal received through the receiving antennas 7a to 7d, and a magnetic field sensor 13 that functions as a body-size information detector. The magnetic field sensor 13 has a function of detecting magnetic field strength at an arranged position as body-size information, and the processing device 12 has a function of controlling the first linear magnetic field generator 9 and the like based on the magnetic field strength detected by the magnetic field sensor 13. Thus, the position detecting apparatus is realized that is capable of generating a magnetic field for position detection having an optimal strength according to a difference in body sizes of subjects.

Claims

1. A position detecting apparatus that performs position detection of a detection subject using a predetermined magnetic field for position detection, comprising:

a magnetic field generator that generates the magnetic field for position detection;

a magnetic field sensor that detects strength of the magnetic field for position detection at a position distant from the magnetic field generator by a distance that is equal to or more than a maximum value of a distance between an area in which the detection subject can be positioned and the magnetic field generator;

a magnetic-field strength controller that controls the strength of the magnetic field for position detection that is generated by the magnetic field generator, based on a detection result by the magnetic field sensor; and

a position calculator that calculates a position of the detection subject using the strength of the magnetic field for position detection detected at a position at which the detection subject is present.

2. The position detecting apparatus according to claim 1, wherein the magnetic-field strength controller controls the magnetic field generator such that the magnetic field strength detected by the magnetic field sensor takes a value equal to or higher than a magnetic field strength that is detectable by the detection subject.

3. The position detecting apparatus according to claim 1, wherein

the detection subject is a body-insertable apparatus that is introduced into a predetermined subject, and

the magnetic field sensor is arranged on an outer surface of the subject.

4. A body-insertable apparatus system comprising:

a body-insertable apparatus that is introduced into a subject and moves inside the subject,

the body-insertable apparatus including

a magnetic field sensor that detects strength of a magnetic field for position detection at a position at which the body-insertable apparatus is present, and

a radio transmitting unit that transmits a radio signal that contains information on the strength of the magnetic field detected by the magnetic field sensor; and

a position detecting apparatus that detects a position of the body-insertable apparatus inside the subject using the predetermined magnetic field for position detection, the position detecting apparatus including

a magnetic field generator that generates the magnetic field for position detection, and

a magnetic-field strength controller that controls the strength of the magnetic field for position detection generated by the magnetic field generator, based on body-size information that corresponds to a shape of an outer surface of the subject.

5. The body-insertable apparatus system according to claim 4, wherein the magnetic-field strength controller controls a driving condition of the magnetic field generator so that the magnetic field for position detection has strength detectable by the magnetic field sensor in all areas in which the body-insertable apparatus can be positioned inside the subject, based on the body-size information.

6. The body-insertable apparatus system according to claim 4, further comprising a body-size information detector that detects the body-size information, wherein

the magnetic-field strength controller controls the strength of the magnetic field for position detection that is generated by the magnetic field generator, based on the body-size information detected by the body-size information detector.

7. The body-insertable apparatus system according to claim 6, wherein

the body-size information detector is arranged at a predetermined position on the outer surface of the subject, and includes a magnetic field sensor unit that detects strength of the magnetic field for position detection at the arranged position as the body-size information, and

the magnetic-field strength controller controls such that the magnetic field strength detected as the body-size information has strength detectable by the magnetic field sensor in the body-insertable apparatus.

8. The body-insertable apparatus system according to claim 4, wherein

the magnetic field generator includes a coil that generates a magnetic field according to power supplied by a predetermined power supply unit, and

the magnetic-field strength controller controls strength of the magnetic field for position detection by adjusting power to be supplied to the coil.

9. The body-insertable apparatus system according to claim 4, wherein

the magnetic field generator includes a coil that generates a magnetic field according to power supplied by a power supply unit constituted of any one of a primary cell and a secondary cell,

the body-insertable apparatus system further comprising

a power determining unit that determines whether the power supply unit is capable of supplying power for a predetermined period, the power corresponding to the magnetic field for position detection having the magnetic field strength acquired by the magnetic-field strength controller, and

a display unit that displays a determination result acquired by the power determining unit.

10. A position detecting method of detecting a position of a body-insertable apparatus that is introduced into a subject and that moves inside the subject using a predetermined magnetic field for position detection, comprising:

a magnetic-field strength detecting step of detecting strength of the magnetic field for position detection at a predetermined position on an outer surface of the subject;

a magnetic-field strength control step of controlling the strength of the magnetic field for position detection based on the magnetic field strength detected at the magnetic-field strength detecting step; and

a position detecting step of detecting a position of the detection subject based on the strength of the magnetic field for position detection of which the strength is controlled at the magnetic-field strength control step at a position at which the detection subject is present.

11. The position detecting method according to claim 10, wherein

the magnetic field for position detection is generated by a coil to which power is supplied by a power supply unit that is constituted of any one of a primary cell and a secondary cell, and

the position detecting method further comprises a determining step of determining whether an amount of retained power that is retained in the power supply unit is sufficient for an amount of a necessary power that is necessary for generating the magnetic field for position detection controlled at the magnetic-field strength control step.