Optical imaging apparatus

• US 6,809,866 B2
• Filed: 07/29/2002
• Issued: 10/26/2004
• Est. Priority Date: 08/03/2001
• Status: Expired due to Term

• Current Assignee: Olympus Corporation
• Original Assignee: Olympus Corporation
• Inventors: Okamura, Toshiro, Kaneko, Mamoru, Kamihara, Yasuhiro, Xie, Tianyu
• Primary Examiner(s): Mack, Ricky
• Assistant Examiner(s): Thomas, Brandi N
• Application Number:
  US10/207,676
• Publication Number:
  US 20030048540A1
• Time in Patent Office: 820 Days
• Field of Search: 359/618, 359/626, 359/627, 359/212, 359/223, 359/224, 359/389, 359/385, 359/233, 359/234, 359/362, 359/368, 359/379, 359/380, 359/381, 359/395, 359/679, 359/639, 359/833, 356/609, 356/450, 356/479, 356/484, 356/497, 356/608, 356/601, 356/607, 600/425, 600/476
• US Class Current: 359/618
• CPC Class Codes: A61B 3/102 for optical coherence tomography [OCT]
• CPC Class Codes: G01N 21/4795 spatially resolved investigating of object in scattering medium in vivo A61B
• CPC Class Codes: G02B 21/0028 specially adapted for specific applications, e.g. for endoscopes, ophthalmoscopes, attachments to conventional microscopes
• CPC Class Codes: G02B 21/0056 based on optical coherence, e.g. phase-contrast arrangements, interference arrangements

Abstract

An optical imaging apparatus includes an optical probe and an apparatus main body which controls and drives the optical probe via a connecting cable. The optical probe includes a low-coherence light source, a half mirror, an XY reflecting mirror scan, an objective optical system, a reflecting mirror, a modulating mirror, and a photo detector. In the optical probe, the modulating mirror and the objective optical system, as optical path length interlockingly adjusting elements, are integrally arranged to an optical path length interlockingly adjusting base, together with a reflecting-side lens. The optical probe has an advancing and regressing driving unit which advances and regresses the optical path length interlockingly adjusting base in the optical axis direction (Z direction).

Claims

1. An optical imaging apparatus comprising:

a low-coherence optical system which guides low-coherence light from a low-coherence light source to a subject portion and further guides return light from the subject portion to light receiving means;

light separating means arranged to said low-coherence optical system, which separates the low-coherence light from said low-coherence light source into instrumentation light and reference light;

horizontal scanning means arranged to said low-coherence optical system, which horizontally scans said subject portion with the instrumentation light separated by said light separating means;

reference light reflecting means arranged to said low-coherence optical system, which reflects the reference light separated by said light separating means and returns the reflected light to said light separating means;

an objective optical system arranged to said low-coherence optical system, which condenses the instrumentation light horizontally scanned by said horizontal scanning means to said subject portion and further captures return instrumentation-light from said subject portion;

optical path length interlockingly adjusting means which interlockingly matches the length of an optical path of said instrumentation light to that of said reference light;

a single drive system that simultaneously drives both said objective optical system and said reference light reflecting means; and

signal processing means which performs signal processing of an electronic signal converted photoelectrically by said light receiving means and obtains a surface image or a tomogram of said subject portion.

4. An optical imaging apparatus according to claim 1, wherein said optical path length interlockingly adjusting means integrally holds at least said objective optical system and said reference light reflecting means, advances and regresses said objective optical system in an optical axis direction of the instrumentation light, and advances and regresses said reference light reflecting means in an optical axis direction of the reference light.

5. An optical imaging apparatus according to claim 1, wherein said low-coherence optical system has light output means which outputs the instrumentation light separated by said light separating means to said horizontal scanning means, and

said optical path length interlockingly adjusting means integrally holds at least said objective optical system and said light output means, and advances and regresses said objective optical system and said light output means in an optical axis direction of the instrumentation light.

6. An optical imaging apparatus according to claim 1, wherein said low-coherence optical system has light output means which outputs the instrumentation light separated by said light separating means to said horizontal scanning means, and

said optical path length interlockingly adjusting means holds said light output means and said reference light reflecting means integrally with said objective optical system, advances and regresses said objective optical system and said light output means in an optical axis direction of the instrumentation light, and advances and regresses said reference light reflecting means in an optical axis of the reference light.

7. An optical imaging apparatus according to claim 1, further comprising an optical scanning probe which transmits the beams of said light source to said subject portion and receives the return light from said subject portion,

wherein said optical scanning probe is a hand-held probe having at least said objective optical system.

8. An optical imaging apparatus according to claim 1, further comprising an optical scanning probe which transmits the beams of said light source to said subject portion and receives the return light from said subject portion,

wherein said optical scanning probe inserted and arranged to an endoscope or a channel for inserting treatment appliance, has at least said objective optical system.

2. An optical imaging apparatus comprising:

an optical system which guides beams from a light source to a subject portion and further guides return light from said subject portion to light receiving means;

optical scanning means arranged to said optical system, which scans said subject portion with the beams from said light source;

an objective optical system arranged to said optical system, which condenses the beams for scanning by said optical scanning means to said subject portion and further captures return light from said subject portion;

positioning means arranged in a field of view for observation of said objective optical system, which comes into contact with said subject portion and performs positioning;

field of view position adjusting means which moves said positioning means relative to said objective optical system in a contact state of said positioning means with said subject portion and adjusts the position in the field of view of said objective optical system; and

signal processing means which performs signal processing of an electronic signal converted photoelectrically by said light receiving means and obtains a surface image or a tomogram of said subject portion;

wherein said optical system has a conjugate focusing optical system between said light source and said objective optical system and said optical imaging apparatus is a conjugate focusing optical imaging apparatus which obtains a conjugate focusing image of said subject portion.

9. An optical imaging apparatus according to claim 2, wherein said light source is a low-coherence light source which generates low-coherence light, and

said optical imaging apparatus is a low-coherence optical imaging apparatus which separates the low-coherence light from said light source into the instrumentation light and the reference light, irradiates said subject portion with the instrumentation light, and obtains a low-coherence light image of said subject portion by making the reference light coherent to the return light from said subject portion.

10. An optical imaging apparatus according to claim 2, wherein said field of view position adjusting means moves said positioning means in the horizontal and vertical directions of said objective optical system.

11. An optical imaging apparatus according to claim 2, wherein said field of view position adjusting means has contact keeping means which keeps a contact state of said positioning means with said subject portion.

12. An optical imaging apparatus according to claim 2, further comprising an optical scanning probe which transmits the beams from said light source to said subject portion and receives the return light from said subject portion, and said optical scanning probe is a hand-held probe having at least said objective optical system.

13. An optical imaging apparatus according to claim 2, further comprising an optical scanning probe which transmits the beams from said light source to said subject portion and receives the return light from said subject portion,

wherein said optical scanning probe inserted and arranged to an endoscope or a channel for inserting treatment appliance, has at least said objective optical system.

3. An optical imaging apparatus comprising:

an optical system which guides beams from a light source to a subject portion and further guides return light from said subject portion to light receiving means;

a normal optical system in which at least a part thereof is the same as said optical system and which has a numerical aperture smaller than that of said optical system, a focusing distance longer than that of said optical system, an object observation range wider than that of said optical system, or a diameter of the object observation range wider than that of said optical system, said normal optical system capturing a normal optical image of said subject portion and forming the captured normal optical image by image pick-up means; and

signal processing means which performs signal processing of an electronic signal photoelectrically converted by said light receiving means, obtains a surface image or a tomogram of said subject portion, performs signal processing the electronic signal converted photoelectrically by said image pick-up means, and obtains a normal optical image;

wherein said optical system has a conjugate focusing optical system between said light source and said objective optical system and said optical imaging apparatus is a conjugate focusing optical imaging apparatus which obtains a conjugate focusing image of said subject portion.

14. An optical imaging apparatus according to claim 3, wherein said light source is a low-coherence light source which generates low-coherence light, and

said optical imaging apparatus is a low-coherence optical imaging apparatus which separates the low-coherence light from said light source into the instrumentation light and the reference light, irradiates said subject portion with the instrumentation light, and obtains a low-coherence light image of said subject portion by making the reference light coherent to the return light from said subject portion.

15. An optical imaging apparatus according to claim 3, further comprising means for differing the numerical apertures, said means having varied apertures depending on the optical systems.

16. An optical imaging apparatus according to claim 3, further comprising means for differing the numerical apertures, said means varying apertures of the stop.

17. An optical imaging apparatus according to claim 3, further comprising means for differing the focusing distances, said means comprising an optical system having two focusing distances.

18. An optical imaging apparatus according to claim 3, further comprising means for differing the focusing distance, said means varying a part of the optical system.