Endoscope apparatus for compensating for change in polarization state during image transmission

• US 5,649,897 A
• Filed: 11/01/1995
• Issued: 07/22/1997
• Est. Priority Date: 11/02/1994
• Status: Expired due to Term

• Current Assignee: Terumo Kabushiki Kaisha (Terumo Corporation)
• Original Assignee: Terumo Kabushiki Kaisha (Terumo Corporation)
• Inventors: Nakamura, Toshihisa, Nudeshima, Masahiro, Hattori, Tomohiko
• Primary Examiner(s): Apley, Richard J.
• Assistant Examiner(s): Leubecker, John P.
• Application Number:
  US08/551,514
• Time in Patent Office: 629 Days
• Field of Search: 600/111, 600/166, 600/181, 600/117, 348/45, 348/58, 348/229, 348/687, 359/435
• US Class Current: 600/111
• CPC Class Codes: A61B 1/00193 adapted for stereoscopic vision
• CPC Class Codes: A61B 1/05 characterised by the image sensor, e.g. camera, being in the distal end portion
• CPC Class Codes: Y10S 600/921 Manipulating image characteristics

Abstract

An endoscope apparatus has an endoscope having an image guide (103) for guiding first and second image light components which have a parallax and can be separated from each other, a memory for storing a predetermined coefficient (a) on the basis of the shape, length, and the like of the image guide, and CCDs for converting the first and second image light components into first and second image signals (A, B). The apparatus performs image processing for generating first and second image data (L, R) by performing proportional distribution processing of the first and second image signals in accordance with the predetermined coefficient.

Claims

1. An image processing apparatus comprising an optical system for transmitting first and second image light components, which have a parallax and can be separated from each other,

conversion means for converting the first and second image light components into first and second image signals;

and

generation means for generating first and second image data by executing proportional distribution processing of the first and second image signals in accordance with a predetermined coefficient.

2. An apparatus according to claim 1, wherein the optical system has an optical fiber, and

the predetermined coefficient is expressed as a function of at least one of a material, diameter, and length of the optical fiber.

3. An apparatus according to claim 2, wherein the predetermined coefficient is expressed as a function of at least one of the material, diameter, and length of the optical fiber, and a pressure externally applied to the optical fiber.

4. An apparatus according to claim 1, wherein the predetermined coefficient is stored in advance in storage means as a function value defined by a shape of the optical system as a parameter.

5. An apparatus according to claim 1, wherein said conversion means comprises image pickup elements for converting the first and second image light components into the first and second image signals as electrical signals, and

said generation means comprises:

inverse conversion means for inversely converting the first and second image signals from said image pickup elements into first and second light intensity data representing light intensities; and

means for performing the proportional distribution processing of the first and second light intensity data in accordance with the predetermined coefficient.

6. An apparatus according to claim 1, wherein the first and second image light components in the optical system have substantially different polarization characteristics.

7. An apparatus according to claim 1, further comprising means for storing or displaying the first and second image data.

8. An endoscope system comprising:

an endoscope having an optical system for transmitting first and second image light components, which have a parallax and can be separated from each other;

conversion means for converting the first and second image light components into first and second image signals; and

generation means for generating first and second image data by executing proportional distribution processing of the first and second image signals in accordance with a predetermined coefficient.

9. A system according to claim 8, wherein the optical system has an optical fiber, and

the predetermined coefficient is expressed as a function of at least one of a material, diameter, and length of the optical fiber.

10. A system according to claim 9, wherein the predetermined coefficient is expressed as a function of at least one of the material, diameter, and length of the optical fiber, and a pressure externally applied to the optical fiber.

11. A system according to claim 8, wherein the predetermined coefficient is stored in advance in storage means as a function value defined by a shape of the optical system as a parameter.

12. A system according to claim 8, wherein said conversion means comprises image pickup elements for converting the first and second image light components into the first and second image signals as electrical signals, and

said generation means comprises:

inverse conversion means for inversely converting the first and second image signals from said image pickup elements into first and second light intensity data representing light intensities; and

means for performing the proportional distribution processing of the first and second light intensity data in accordance with the predetermined coefficient.

13. A system according to claim 8, wherein the first and second image light components in the optical system have substantially different polarization characteristics.

14. A system according to claim 8, further comprising means for storing or displaying the first and second image data.

15. A system according to claim 13, wherein the optical system of said endoscope comprises an optical fiber, a light input portion arranged at a distal end portion of said optical fiber, and a light output portion arranged at a proximal end portion of said optical fiber, and

said light input portion comprises a pair of filters which are arranged at or near an effective center in an optical axis direction as an aperture position of the observation lens, have different azimuth angles of polarization, and are divisionally arranged on right and left regions of a surface substantially perpendicular to the optical axis.

16. A system according to claim 15, wherein each of said pair of polarization filters has a semi-circular shape.

17. A system according to claim 13, wherein the optical system of said endoscope comprises an optical fiber, a light input portion arranged at a distal end portion of said optical fiber, and a light output portion arranged at a proximal end portion of said optical fiber, and

said light output portion comprises:

polarization axis rotation means for time-divisionally rotating axes of polarization of two polarized light images transmitted through said optical fiber; and

an analyzer arranged behind said polarization axis rotation means.

18. A system according to claim 13, wherein the optical system of said endoscope comprises an optical fiber, a light input portion arranged at a distal end portion of said optical fiber, and a light output portion arranged at a proximal end portion of said optical fiber, and

said light output portion comprises:

a beam splitter for splitting optical paths of two polarized light images transmitted through said optical fiber; and

a pair of polarization filters which respectively transmit the split polarized light images and have different azimuth angles of polarization.

19. A system according to claim 13, wherein the optical system of said endoscope comprises an optical fiber, a light input portion arranged at a distal end portion of said optical fiber, and a light output portion arranged at a proximal end portion of said optical fiber, and

said light output portion comprises a pair of polarization filters which are arranged adjacent to each other at a position near an exit of said optical fiber, and have different azimuth angles of polarization to respectively transmit two polarized light images from said optical fiber.

20. A system according to claim 13, wherein the optical system of said endoscope comprises an optical fiber, a light input portion arranged at a distal end portion of said optical fiber, and a light output portion arranged at a proximal end portion of said optical fiber, and

said light output portion comprises a plurality of first polarization filters and a plurality of second polarization filters, which have different azimuth angles of polarization so as to respectively transmit two polarized light images from said optical fiber.

21. A system according to claim 13, further comprising a light guide disposed near the optical system.

22. A system according to claim 13, wherein the optical system of said endoscope comprises an optical fiber, a light input portion arranged at a distal end portion of said optical fiber, and a light output portion arranged at a proximal end portion of said optical fiber, and

said light output portion comprises:

an illumination light source arranged near said light output portion; and

means for guiding illumination light from said illumination light source toward said proximal end portion of said optical fiber,

whereby said optical fiber serves as a bidirectional optical fiber, and is used as a light guide for illuminating an object.

23. A system according to claim 13, wherein the optical system of said endoscope comprises an optical fiber, a light input portion arranged at a distal end portion of said optical fiber, and a light output portion arranged at a proximal end portion of said optical fiber, and

the optical system further comprises an image reflection member at a distal end of said light input portion.

24. A system according to claim 23, wherein said image reflection member comprises one of a mirror surface and a prism having a mirror surface.

25. A system according to claim 13, wherein said optical system comprises an imaging member.

26. A system according to claim 13, wherein the optical system of said endoscope comprises a light transmission path consisting of a relay lens, a light input portion arranged at a distal end side of said light transmission path, and a light output portion arranged at a proximal end side of said light transmission path.

27. A system according to claim 13, further comprising a pair of solid-state image pickup elements arranged behind the optical system of said endoscope.

28. A method of controlling an endoscope having an optical system for transmitting first and second image light components, which have a parallax and can be separated from each other, comprising the steps of:

converting the first and second image light components into first and second image signals by controlling image pickup elements; and

generating first and second image data by performing proportional distribution processing of the first and second image signals on the basis of conversion characteristics of the image pickup elements and a predetermined coefficient representing a shape of the optical system.

29. A method according to claim 28, wherein the predetermined coefficient is stored as a value corresponding to a geometric shape of the optical system.