Endoscopic image processing system capable of estimating absolute shape of object entity

• US 6,295,368 B1
• Filed: 04/08/1999
• Issued: 09/25/2001
• Est. Priority Date: 04/10/1998
• Status: Active Grant

• Current Assignee: Olympus Optical Corporation Limited (Olympus Corporation)
• Original Assignee: Olympus Optical Corporation Limited (Olympus Corporation)
• Inventors: Hasegawa, Jun, Nonami, Tetsuo
• Primary Examiner(s): Johns, Andrew W.
• Assistant Examiner(s): NAKHJAVAN, SHERVIN K
• Application Number:
  US09/288,492
• Time in Patent Office: 901 Days
• Field of Search: 382/128, 382/130, 382/131, 382/132, 382/154, 382/203, 382/206, 382/276, 382/285, 382/286, 382/291, 382/294, 382/305, 606/32, 606/33, 606/34, 606/46, 606/47, 606/48, 348/45, 348/65, 348/72
• US Class Current: 382/128
• CPC Class Codes: A61B 1/05 characterised by the image sensor, e.g. camera, being in the distal end portion
• CPC Class Codes: A61B 5/062 using magnetic field
• CPC Class Codes: A61B 5/1076 for measuring dimensions inside body cavities, e.g. using catheters A61B3/1005 takes precedence

Abstract

An endoscopic system comprises an endoscope system, an endoscopic position detecting apparatus, and an image processing apparatus. The endoscope system enables endoscopic examinations. The endoscopic position detecting apparatus detects the three-dimensional positions of the distal part of the endoscope in a body cavity. The image processing apparatus estimates the shape of an object entity visualized by the endoscope. The image processing apparatus is used as a means for grasping the shape of an object entity in a body cavity. For this purpose, the insertion unit of an electronic endoscope is inserted into the body cavity of a patient lying down on a patient couch. Specifically, a main unit of the image processing apparatus is connected to a video processor over a cable, and receives an image signal (R, G, and B signals and a sync signal) sent from the video processor. The main unit of the image processing apparatus estimates relative shapes according to successive image signals representing the object entity and being sent from the video processor. The main unit of the image processing apparatus then calculates the absolute shape of the object entity according to the position data of the distal part of the electronic endoscope sent from a main unit of the endoscopic position detecting apparatus.

Claims

1. An endoscopic image processing system, comprising:

an imaging device which produces endoscopic images of a subject through an objective;

an image memory which stores a plurality of images produced by the imaging device;

a relative shape estimator which estimates relative shapes depicted by the plurality of images according to image signals representing the plurality of images stored in the memory;

a first coil located near the objective;

a position information detector, having a second coil disposed at a predetermined position, which detects the positions of the first coil by utilizing magnetic fields;

a position information acquiring unit which obtains position information of the positions detected by the position information detector in association with the respective images stored in the image information memory; and

a subject shape estimator which estimates the shape of the subject according to the relative shape information of the relative shapes estimated by the relative shape estimator and the position information acquired by the position information acquiring unit.

2. An endoscopic image processing system, comprising:

an endoscope having an insertion unit provided with a distal part and a bending portion capable of being angled;

an objective located in the distal part of the insertion unit;

an imaging unit which obtains an image of a subject through the objective;

an image memory which stores a plurality of endoscopic images produced by the imaging unit;

a relative shape estimator which estimates relative shapes depicted by the plurality of endoscopic images according to image signals representing the plurality of endoscopic images stored in the image memory;

a first coil located in the distal part of the insertion unit;

a position information detector, having a second coil disposed at a predetermined position, which detects the positions of the first coil by utilizing magnetic fields;

a position information acquiring unit which obtains position information of the positions detected by the position information detector in association with the respective endoscopic images stored in the image information memory; and

a subject shape estimator which estimates the shape of the subject according to the relative shape information of the relative shapes estimated by the relative shape estimator and the position information acquired by the position information acquiring unit.

3. A shape estimating method, comprising the steps of:

producing subject images through an objective using an imaging unit;

storing a plurality of subject images produced by the imaging unit;

estimating relative shapes depicted by the plurality of subject images according to image signals representing the plurality of stored subject images;

detecting the positions of a first coil located near the objective using magnetic fields by way of a position information detector having a second coil disposed at a predetermined position;

acquiring position information of the detected positions in association with the respective stored subject images; and

estimating the shape of the subject according to the relative shape information of the estimated relative shapes and the acquired position information.

4. An endoscopic image processing system, comprising:

an endoscope having an imaging device which images an object entity at different positions;

a relative shape estimator which estimates relative shapes of the object entity using a plurality of images produced by the imaging device;

a position detector which detects positions in a three-dimensional space of a distal part of the endoscope by utilizing a coil; and

an estimator which estimates an absolute shape of the object entity according to the relative shapes of the estimated object entity and the output of the position detector.

5. An endoscopic image processing system according to claim 4, wherein the position detector includes a source coil which generates magnetic fields and is disposed in the distal part of the endoscope;

and a plurality of sense coils which detect magnetic fields generated by the source oil, the sense coils being arranged in a three-dimensional space,

the position detector being operable to detect the positions in three-dimensional space of the source coil according to the outputs of the sense coils.

6. An endoscopic image processing apparatus according to claim 5, wherein the source coil is a single-core coil.

7. An endoscopic image processing apparatus according to claim 5, wherein the sense coils are single-core coils.

8. An endoscopic image processing apparatus according to claim 5, wherein the sense coils are triaxial coils.

9. An endoscopic image processing system according to claim 4, wherein the position detector includes a plurality of source coils which generate magnetic fields and are arranged in the three-dimensional space;

and a sense coil which detects the magnetic fields generated by the source coils and is disposed in the distal part of the endoscope,

the position detector being operable to detect the positions in the three-dimensional space of the sense coil according to the output of the sense coil.

10. An endoscopic image processing apparatus according to claim 9, wherein the source coils are single-core coils.

11. An endoscopic image processing apparatus according to claim 9, wherein the sense coil is a single-core coil.

12. An endoscopic image processing apparatus according to claim 9, wherein the sense coil is a triaxial coil.

13. An endoscopic image processing apparatus according to claim 4, further comprising a synchronizing unit which synchronizes timing of the position detector performing its function of detecting a position with the timing of the imaging unit performing its function of imaging an object entity.

14. An endoscopic image processing apparatus according to claim 4, further comprising a two-dimensional image producing unit which depicts the absolute shape of the object entity observed at any observation point.

15. An endoscopic image processing apparatus according to claim 4, further comprising a memory which stores a plurality of images produced by the imaging unit and the information of the positions of the distal part of the endoscope detected by the position detector.

16. An endoscopic image processing apparatus according to claim 15, wherein time instants at which the imaging unit produces endoscopic images, and time instants at which the position detector detects the positions of the distal part of the endoscope are stored in the memory in association with the image or position data items.

17. An endoscopic image processing apparatus according to claim 16, wherein the position detector includes a position estimator which estimates the positions at which the distal part of the endoscope are located:

(i) at the time instants at which the imaging unit produces the images;

(ii) according to the positions of the distal part of the endoscope stored in the memory;

(iii) the time instants at which the position detector detects the positions of the distal part of the endoscopic; and

(iv) the time instants at which the imaging unit produces the endoscopic images.

18. An endoscopic image processing apparatus according to claim 17, wherein the position estimator includes an interpolating unit which calculates the positions of the distal part of the endoscope at time instants by performing interpolation according to the plurality of positions of the distal part of the endoscope and the detected time instants which are stored in the memory;

and the positions of the distal part of the endoscope are estimated according to the time instant at which the endoscopic images are produced and stored in the memory, and the output of the interpolating unit.