Method and apparatus for infrared imaging in small passageways

• US 20020076178A1
• Filed: 12/20/2000
• Published: 06/20/2002
• Est. Priority Date: 12/21/2000
• Status: Active Grant

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Klocek, Paul, Anderson, Douglas W.
• Granted Patent: US 6,735,462 B2
• Time in Patent Office: Days
• US Class Current: 385/106
• CPC Class Codes: A61B 5/015 By temperature mapping of body part
• CPC Class Codes: A61B 5/02007 Evaluating blood vessel condition, e.g. elasticity, compliance
• CPC Class Codes: G02B 23/2423 of the distal end
• CPC Class Codes: G02B 23/26 using light guides for illumination G02B23/2469
• CPC Class Codes: G02B 6/06 the relative position of the fibres being the same at both ends, e.g. for transporting images
• CPC Class Codes: G02B 6/4206 Optical features G02B6/4207, G02B6/421 take precedence
• CPC Class Codes: G02B 6/4249 comprising arrays of active devices and fibres
• CPC Class Codes: G02B 6/4298 coupling with non-coherent light sources and/or radiation detectors, e.g. lamps, incandescent bulbs, scintillation chambers

Abstract

An infrared imaging system (10) includes a catheter (11). The catheter is inserted into a small passageway, such as a blood vein (23), in order to collect infrared information from the vein. The information is refracted by at least one lens (32, 46, 52, 57, 63) in a collecting section (17, 45, 56, 61) of the catheter, and is imaged onto the ends (38) of an array of optical fibers (34). The fibers transmit the information to a relay lens (42), which images the information onto respective detector elements of an infrared detector (12). The infrared detector converts the information received from the relay lens into electrical information, which is transmitted to a circuit (13). The circuit generates electrical data that is transmitted to a display (16), which displays a visible image based on the infrared radiation emitted by the scene.

Claims

1. An apparatus comprising:

an elongate optical portion which has first and second ends and which can transmit infrared image information from said first end to said second end;

a first section which collects infrared image information and supplies it to said first end of said optical portion; and

a second section which includes an infrared image detector that receives infrared image information from said second end of said optical portion.

2. An apparatus according to claim 1, wherein said optical portion is flexible.

3. An apparatus according to claim 2, wherein said optical portion includes a plurality of optical fibers, and wherein each said fiber includes two end portions which are respectively disposed at said first and second ends.

4. An apparatus according to claim 3,

wherein each said fiber includes a cladding and includes a core disposed within said cladding;

and

including a plurality of lens portions which are each associated with and supported in alignment with a respective said fiber at said first end of said elongate portion, and which each concentrate onto said core of said associated fiber the radiation which would otherwise impinge on said cladding of said associated fiber.

5. An apparatus according to claim 4, including a plurality of further lens portions which are each associated with and supported in alignment with a respective said fiber at said second end of said elongate portion, and which each receive and deconcentrate radiation from the core of said associated fiber.

6. An apparatus according to claim 3, wherein said optical fibers each have a coating which reduces friction between said optical fibers.

7. An apparatus according to claim 3, wherein said first section includes an aperture stop, and wherein infrared image information collected by said first section passes through said aperture stop.

8. An apparatus according to claim 3, further comprising a sheath, said sheath sealing said optical fibers within said sheath between said first and second ends to form a protective barrier for said optical fibers.

9. An apparatus according to claim 8, wherein said first section includes a sleeve, said sleeve being supported by said first end of said optical portion, and said sleeve supporting said first section.

10. An apparatus according to claim 9, wherein said first section includes an objective lens supported by said sleeve, said objective lens imaging infrared information collected by said first section.

11. An apparatus according to claim 10, wherein said objective lens is configured to operate within approximately one centimeter of a scene that emits infrared information supplied to said first end of said optical portion, and wherein the distance that radiation travels from said first end to said infrared image detector through said optical portion is substantially longer than a distance that radiation travels from said scene to said first end.

12. An apparatus according to claim 10, wherein said first section includes a conical reflective surface supported by said sleeve, said reflective surface reflecting to said objective lens infrared information being supplied by said first section to said first end of said optical portion.

13. An apparatus according to claim 10, wherein said first section includes an additional lens supported by said sleeve, said additional lens cooperating with said objective lens to supply infrared image information to said first end of said optical portion.

14. An apparatus according to claim 10, wherein said first section includes a reflective surface supported by said sleeve, said reflective surface reflecting infrared information to said objective lens of said first section.

15. An apparatus according to claim 3, wherein said infrared image detector is an uncooled detector and includes an array of detector elements, and wherein infrared radiation traveling through each of said fibers is directed onto a respective said detector element.

16. An apparatus according to claim 1, wherein said first section and said optical portion each have a maximum transverse dimension less than approximately 3000 micrometers.

17. An apparatus according to claim 1, wherein said second section includes a relay lens, said relay lens being positioned optically between said infrared image detector and said second end, and directing infrared image information received from said second end onto said infrared image detector.

20. A method according to claim 19, further comprising the step of displaying on a display an image representing infrared image information detected by said image detector.

21. A method according to claim 19, wherein said receiving step includes the step of directing infrared image information received from said second end onto said infrared image detector using a relay portion positioned optically between said infrared image detector and said second end.

22. A method according to claim 19, wherein said collecting step includes the step of blocking unwanted infrared radiation using an aperture stop, and wherein infrared image information supplied to said first end has passed through said aperture stop.

18. An apparatus comprising:

an elongate optical portion which has first and second ends and which can transmit infrared image information from said first end to said second end, said optical portion including a plurality of optical fibers that each have two end portions respectively disposed at said first and second ends; and

a first section which collects infrared image information and supplies it to said first end of said optical portion, said optical portion being flexible, said first section and said optical portion each having a maximum transverse dimension less than approximately 3000 micrometers.

19. A method comprising the steps of:

transmitting infrared image information through an elongate optical portion from a first end thereof to a second end thereof;

collecting infrared image information and supplying it to said first end of said optical portion; and

receiving infrared image information at a section which includes an infrared image detector and which directs infrared image information from said second end of said optical portion onto said image detector.