Method and apparatus for fiberscope

• US 7,522,797 B2
• Filed: 05/14/2007
• Issued: 04/21/2009
• Est. Priority Date: 09/03/2004
• Status: Active Grant

• Current Assignee: Chemimage Corporation
• Original Assignee: Chemimage Corporation
• Inventors: Demuth, Joseph, Nelson, Matthew, Treado, Patrick
• Primary Examiner(s): AMARI, ALESSANDRO V
• Application Number:
  US11/798,483
• Publication Number:
  US 20070280612A1
• Time in Patent Office: 708 Days
• Field of Search: 385/116, 385/117, 385/119, 356/301, 600/160, 600/177, 600/181
• US Class Current: 385/117
• CPC Class Codes: A61B 1/00165 with light-conductive means, e.g. fibre optics A61B1/07 takes precedence
• CPC Class Codes: A61B 1/043 for fluorescence imaging
• CPC Class Codes: A61B 1/07 using light-conductive means, e.g. optical fibres
• CPC Class Codes: A61B 5/0075 by spectroscopy, i.e. measuring spectra, e.g. Raman spectroscopy, infrared absorption spectroscopy A61B5/0071 takes precedence
• CPC Class Codes: A61B 5/0084 for introduction into the body, e.g. by catheters A61B5/1459 takes precedence
• CPC Class Codes: G01J 2003/1213 Filters in general, e.g. dichroic, band
• CPC Class Codes: G01J 3/02 Details
• CPC Class Codes: G01J 3/021 using plane or convex mirrors, parallel phase plates, or particular reflectors
• CPC Class Codes: G01J 3/0218 using optical fibers
• CPC Class Codes: G01J 3/0256 Compact construction
• CPC Class Codes: G01J 3/0264 Electrical interface; User interface
• CPC Class Codes: G01J 3/0291 Housings; Spectrometer accessories; Spatial arrangement of elements, e.g. folded path arrangements
• CPC Class Codes: G01J 3/32 Investigating bands of a spectrum in sequence by a single detector
• CPC Class Codes: G01J 3/44 Raman spectrometry; Scattering spectrometry ; Fluorescence spectrometry
• CPC Class Codes: G01N 2021/3155 Measuring in two spectral ranges, e.g. UV and visible
• CPC Class Codes: G01N 2021/4742 comprising optical fibres
• CPC Class Codes: G01N 2021/6419 Excitation at two or more wavelengths
• CPC Class Codes: G01N 2021/6421 Measuring at two or more wavelengths
• CPC Class Codes: G01N 2021/6484 Optical fibres
• CPC Class Codes: G01N 2021/656 Raman microprobe
• CPC Class Codes: G01N 21/33 : using ultraviolet light G01N21/39 takes precedence
• CPC Class Codes: G01N 21/359 : using near infrared light
• CPC Class Codes: G01N 21/474 : Details of optical heads therefor, e.g. using optical fibres
• CPC Class Codes: G01N 21/645 : Specially adapted constructive features of fluorimeters
• CPC Class Codes: G01N 21/65 : Raman scattering
• CPC Class Codes: G02B 23/2423 : of the distal end
• CPC Class Codes: G02B 23/2469 : using optical fibres
• 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 6/29398 : Temperature insensitivity

Abstract

The disclosure generally relates to a method and apparatus for a fiberscope. In one embodiment, the disclosure relates to a chemical imaging fiberscope for imaging and collecting optical spectra from a sample having at least one illumination fiber for transmitting light from a first an a second light source to a distal end of a fiberscope; a dichroic mirror disposed at said distal end of the fiberscope such that light from said first light source passes substantially straight through said mirror and light of a predetermined wavelength from said second light source is substantially reflected by said mirror toward said sample to thereby illuminate said sample; and at least one collection fiber for receiving light from said illuminated sample and transmitting the received light to an optical device.

Claims

1. A method of for chemical imaging and collecting at least one spectra from a sample comprising:

transmitting light from a first and a second light source with at least one illumination fiber;

substantially transmitting light from said first light source through a dichroic mirror disposed at the distal end of said at least one illumination fiber while substantially reflecting with said dichroic mirror light of a predetermined wavelength from said second light source toward said sample to thereby illuminate said sample;

receiving light from said illuminated sample; and

transmitting the received light to one or more optical device with at least one collection fiber.

2. The method of claim 1 further comprising transmitting light exclusively from said first light source via one of plural illumination fibers wherein said at least one illumination fiber comprises said plural illumination fibers.

3. The method of claim 1 further comprising rejecting said predetermined wavelength of light from said second light source with a spectral filter disposed between said sample and said at least one collection fiber.

4. The method of claim 3 wherein said predetermined wavelength is approximately 670 nanometers.

5. The method of claim 3 wherein said predetermined wavelength comprises at least one wavelength each of which is in a range of wavelengths from 220 to 1500 nanometers.

6. The method of claim 3 wherein said predetermined wavelength comprises at least one wavelength each of which is in a range of wavelengths from 500 to 850 nanometers.

7. The method of claim 3 wherein said predetermined wavelength comprises at least one wavelength each of which is in a range of wavelengths from 270 to 550 nanometers.

8. The method of claim 1 wherein said second light source is a laser.

9. The method of claim 1 wherein said first light source is a broadband near infrared light source.

10. The method of claim 1 wherein said second light source is a broadband near infrared light source.

11. The method of claim 1 wherein said second light source is a broadband visible light source.

12. The method of claim 1 wherein said second light source is a broadband ultraviolet light source.

13. The method of claim 1 further comprising:

transmitting light exclusively from said first light source via one of plural illumination fibers; and

transmitting light exclusively from said second light source via another of said plural illumination fibers

wherein said at least one illumination fibers comprises said plural illumination fibers.

14. The method of claim 1 further comprising transmitting light with said at least one illumination fiber from said first light source, said second light source, and a third light sources to said distal end of said at least one illumination fiber.

15. The method of claim 14 wherein said first light source is a broadband near infrared light source, said second light source is a laser, and said third light source is a broadband visible light source.

16. The method of claim 1 wherein the optical device is an optical spectrometer adapted to be used with one or more of a Raman spectra, VIS/NIR spectra or Fluorescence Spectra.

17. The method of claim 1 wherein said optical device is a chemical imaging spectrometer and detector configured to perform chemical imaging for Raman, VIS/NIR and fluorescence.

18. The method of claim 1 further comprising receiving scattered light from said illuminated sample with said at least one collection fiber.

19. The method of claim 1 further comprising receiving Raman scattered light from said illuminated sample with said at least one collection fiber.

20. The method of claim 1 further comprising receiving reflected light from said illuminated sample with said at least one collection fiber.

21. The method of claim 1 further comprising receiving flouresced light from said illuminated sample with said at least one collection fiber.

22. The method of claim 1 wherein the light received by said at least one collection fiber has a wavelength in a range of wavelengths shifted from the illuminating wavelength by −

4000 to +4000 wavenumbers (cm<sup>−

1</sup>).

23. The method of claim 1 further comprising controlling the angular field of view of said at least one collection fiber via a spatial filter disposed between said sample and said at least one collection fiber.

24. The method of claim 1 wherein the optical properties of said dichroic mirror are insensitive to temperature changes.

25. The method of claim 1 wherein the optical properties of said dichroic mirror are insensitive to humidity changes.

26. The method of claim 1 further comprising disposing a lens between said sample and said at least one collection fiber.

27. The method of claim 1 further comprising enclosing in a housing said at least one illumination fiber, said at least one collection fiber, and said dichroic mirror.

28. The method of claim 27 including a window at said distal end of said housing.

29. The method of claim 28 wherein said window is substantially composed of a material selected from the group consisting of quartz, diamond, sapphire, plastic, glass, and semiconductor.

30. The method of claim 28 further comprising filtering the light from said first light source with a first portion of said window which is spatially patterned for filtering said first light source wherein said window includes a second portion which is transparent for the light from said illuminated sample.

31. The method of claim 1 further comprising alternately connecting either said first or said second light source to said at least one illumination fiber selectably via a switch,

wherein said switch connects said first light source to said illumination fiber for guiding said fiberscope to said sample and wherein said switch connects said second light source to said illumination fiber for illuminating said sample.

32. A method for imaging and collecting spectra from a sample comprising:

operatively connecting a near infrared (“

NIR”

) light source and a laser light source to a proximate end of at least one illumination fiber

transmitting light from said near infrared (“

NIR”

) light source and said laser light source with said at least one illumination fiber to a dichroic mirror disposed in proximity to the distal end of said illumination fiber;

allowing light from said NIR light source to pass substantially straight through said mirror;

substantially reflecting light from said laser light source toward said sample with said mirror to thereby illuminate said sample;

receiving with at least one collection fiber light from said illuminated sample; and

transmitting the received light to an optical device for imaging and collecting the spectra of said sample.

33. The method of claim 32 further comprising rejecting light having a wavelength substantially the same as the wavelength of light emitted by said laser light source with a spectral filter disposed between said sample and said collection fiber.

34. The method of claim 33 further comprising controlling the angular field of view of said collection fiber with a spatial filter disposed between said sample and said collection fiber.

35. The method of claim 34 further comprising a lens disposed between said sample and said collection fiber.

36. The method of claim 35 further comprising a housing for enclosing said at least one illumination fiber, said at least on collection fiber, said dichroic mirror, said spectral filter, said spatial filter, and said lens.

37. The method of claim 36 including a window at said distal end of said housing.

38. The method of claim 37 wherein said window is substantially composed of a material selected from the group consisting of quartz, diamond, sapphire, plastic, glass, and semiconductor.

39. The method of claim 38 further comprising filtering light from said NIR light source with a first portion of said window which is spatially patterned for filtering the light

wherein said window has a second portion which is transparent for the light from said illuminated sample.

40. The method of claim 37 further comprising alternately connecting either said NIR light source or said laser light source to said illumination fiber with a switch,

wherein said switch connects said NIR light source to said illumination fiber for guiding said fiberscope to said sample and wherein said switch connects said laser light source to said illumination fiber for illuminating said sample.

41. The method of claim 32 wherein the optical device is an optical spectrometer adapted to be used with one or more of a Raman spectra, VIS/NIR spectra or Fluorescence Spectra.

42. The method of claim 32 wherein said optical device is a chemical imaging spectrometer and detector configured to perform chemical imaging for Raman, VIS/NIR and fluorescence.

43. The method of claim 32 wherein the light received by said collection fiber is scattered from said illuminated sample.

44. The method of claim 32 wherein the light received by said collection fiber is Raman scattered from said illuminated sample.

45. The method of claim 32 wherein the light received by said collection fiber is reflected from said illuminated sample.

46. The method of claim 32 wherein the light received by said collection fiber is fluoresced from said illuminated sample.

47. The method of claim 32 wherein the light received by said at least one collection fiber has a wavelength in a range of wavelengths shifted from the illuminating wavelength by −

4000 to =4000 wavenumbers (cm<sup>−

1</sup>).