Capsule endoscope apparatus

Abstract

A signal processing circuit of an external device includes a CPU and a memory which are not shown. A program for estimating at least one of the position and orientation of a capsule endoscope on the basis of strength signals received through respective antennas is installed in the signal processing circuit. A single-core coil to generate a magnetic field is arranged in the capsule endoscope. The generated magnetic field is detected by a plurality of coils arranged outside a body, whereby a distance that the capsule endoscope has traveled can be obtained with accuracy. This arrangement controls image-capture timing to reliably capture images necessary for a diagnosis and prevent unnecessary image capture.

1 . A capsule endoscope apparatus comprising an image capturing unit for capturing an image in a body to transmit the image by radio and a receiving unit for receiving the image transmitted by radio from the image capturing unit to record the image, the apparatus further comprising:
 an estimating unit for receiving a signal transmitted by radio from the image capturing unit through each of a plurality of antennas arranged at different positions outside the body to estimate at least one of the position and orientation of the image capturing unit on the basis of the signals received through the antennas; and   a control unit for controlling image capture by the image capturing unit using information regarding at least one of the position and orientation estimated by the estimating unit.   
     
     
         2 . The capsule endoscope apparatus according to  claim 1 , wherein
 the control unit includes:   a distance calculating unit for calculating a distance that the image capturing unit has traveled on the basis of a plurality of positions of the image capturing unit obtained by the estimating unit; and   an image-capture control unit for controlling image capture by the image capturing unit on the basis of the distance.   
     
     
         3 . The capsule endoscope apparatus according to  claim 2 , wherein
 the distance calculating unit includes a unit for calculating a predicted distance on the basis of the plurality of positions of the image capturing unit obtained by the estimating unit.   
     
     
         4 . The capsule endoscope apparatus according to  claim 3 , wherein the predicted distance is calculated using an approximation function derived from the plurality of positions of the image capturing unit obtained by the estimating unit. 
     
     
         5 . The capsule endoscope apparatus according to  claim 2 , wherein
 the control unit includes:   an orientation-change calculating unit for calculating a change in orientation of the image capturing unit on the basis of a plurality of orientations obtained by the estimating unit; and   an image-capture control unit for controlling image capture by the image capturing unit on the basis of the distance and the change in orientation.