Method and apparatus for compact dispersive imaging spectrometer

• US 7,307,705 B2
• Filed: 03/01/2006
• Issued: 12/11/2007
• Est. Priority Date: 07/18/2003
• Status: Active Grant

• Current Assignee: Chemimage Corporation
• Original Assignee: Chemimage Corporation
• Inventors: Treado, Patrick J.
• Primary Examiner(s): EVANS, FANNIE L
• Application Number:
  US11/364,180
• Publication Number:
  US 20060146315A1
• Time in Patent Office: 650 Days
• Field of Search: 356/301, 356/317, 356/318, 250/458.1, 250/459.1, 250/461.1, 250/461.2
• US Class Current: 356/73
• CPC Class Codes: G01J 3/02 Details
• CPC Class Codes: G01J 3/0224 using polarising or depolarising elements
• CPC Class Codes: G01J 3/0229 using masks, aperture plates, spatial light modulators or spatial filters, e.g. reflective filters
• CPC Class Codes: G01J 3/0256 Compact construction
• CPC Class Codes: G01J 3/0264 Electrical interface; User interface
• CPC Class Codes: G01J 3/0272 Handheld
• CPC Class Codes: G01J 3/0283 using a charging unit
• CPC Class Codes: G01J 3/10 Arrangements of light sources specially adapted for spectrometry or colorimetry
• CPC Class Codes: G01J 3/44 Raman spectrometry; Scattering spectrometry ; Fluorescence spectrometry
• CPC Class Codes: G01J 3/4406 Fluorescence spectrometry
• CPC Class Codes: G01N 2021/6417 Spectrofluorimetric devices
• CPC Class Codes: G01N 2021/6423 Spectral mapping, video display
• CPC Class Codes: G01N 2021/6471 Special filters, filter wheel
• CPC Class Codes: G01N 21/6456 Spatial resolved fluorescence measurements; Imaging
• CPC Class Codes: G01N 21/65 Raman scattering
• CPC Class Codes: G01N 2201/0221 Portable; cableless; compact; hand-held
• CPC Class Codes: G01N 2201/0627 Use of several LED's for spectral resolution
• CPC Class Codes: G02F 1/133371 Cells with varying thickness of the liquid crystal layer
• CPC Class Codes: G02F 1/1347 Arrangement of liquid crystal layers or cells in which the final condition of one light beam is achieved by the addition of the effects of two or more layers or cells

Abstract

The disclosure generally relates to a method and apparatus for compact dispersive imaging spectrometer. More specifically, one embodiment of the disclosure relates to a portable system for obtaining a spatially accurate wavelength-resolved image of a sample having a first and a second spatial dimension. The portable system can include a photon emission source for sequentially illuminating a plurality of portions of said sample with a plurality of photons to produce photons scattered by the sample. The photon emission source can illuminate the sample along the first spatial dimension for each of plural predetermined positions of the second spatial dimension. The system may also include an optical lens for collecting the scattered photons to produce therefrom filtered photons, a dispersive spectrometer for determining a wavelength of ones of the filtered photons, a photon detector for receiving the filtered photons and obtaining therefrom plural spectra of said sample, and a processor for producing a two dimensional image of said sample from the plural spectra.

Claims

1. A portable system for obtaining a two dimensional image of a sample having a first and a second spatial dimension, comprising:

a photon emission source for sequentially illuminating a portion of said sample with a plurality of photons to thereby produce photons scattered by the sample wherein the photon emission source illuminates said sample along the first spatial dimension for each of plural predetermined positions of the second spatial dimension;

an optical lens for collecting the scattered photons to produce therefrom filtered photons;

a dispersive spectrometer for determining a wavelength of ones of the filtered photons;

a photon detector for receiving the filtered photons and obtaining therefrom a spectrum of said sample; and

a processor for producing a two dimensional image of said sample which includes information from said spectrum.

2. The system of claim 1 wherein said photon detector is selected from the group consisting of:

charge-coupled device, complementary metal oxide semiconductor, charge injection device, intensified charge injection device, electron multiplying charge-coupled device, silicon photo diode, silicon avalanche diode, and focal plane array.

3. The system of claim 1 wherein said photon emission source is a laser.

4. The system of claim 1 wherein said photon emission source is a light emitting diode.

5. The system of claim 4 wherein said light emitting diode is disposed as a ring.

6. The system of claim 5 wherein said light emitting diode is a plurality of light emitting diodes.

7. The system of claim 4 wherein said light emitting diode is a plurality of light emitting diodes wherein one of said plural light emitting diodes emits photons at a wavelength that is different than a wavelength of photons emitted by another of said plural light emitting diodes.

8. The system of claim 7 wherein the wavelength of photons emitted by one of said plural light emitting diodes is in the ultraviolet wavelength range.

9. The system of claim 7 wherein the wavelength of photons emitted by one of said plural light emitting diodes is in the near infrared wavelength range.

10. The system of claim 1 wherein said spectrum is obtained over a predetermined period of time and said sample is stationary during said predetermined period of time.

11. The system of claim 1 wherein said scattered photons include photons emitted by said sample.

12. The system of claim 1 wherein said spectrum is a Raman spectrum.

13. The system of claim 1 wherein the system is a hand-held system.

14. The system of claim 1 wherein said optical lens includes a laser rejection filter.

15. The system of claim 1 wherein said spectrum is a fluorescence spectrum.

16. The system of claim 1 wherein said spectrum is a near infrared spectrum.

17. A method for obtaining a two dimensional image of a sample using a hand-held device, the method comprising the steps of:

providing a sample having a first and a second spatial dimension;

sequentially illuminating a portion of said sample with a plurality of photons from a photon emission source to thereby produce photons scattered by the sample the sequential illumination occurring alone the first spatial dimension for each of plural predetermined positions of the second spatial dimension;

collecting the scattered photons and producing therefrom filtered photons;

determining a wavelength of ones of the filtered photons;

receiving the filtered photons in a photon detector and obtaining therefrom a spectrum of said sample; and

processing the spectra and producing therefrom a two dimensional image of said sample which includes information from said spectrum.

18. The method of claim 17 wherein the step of illuminating the sample is accomplished by illuminating the sample with plural light emitting diodes wherein one of said plural light emitting diodes emits photons at a wavelength that is different than a wavelength of photons emitted by another of said plural light emitting diodes.

19. The method of claim 18 wherein the wavelength of photons emitted by one of said plural light emitting diodes is in the ultraviolet wavelength range.

20. The method of claim 18 wherein the wavelength of photons emitted by one of said plural light emitting diodes is in the near infrared wavelength range.

21. The method of claim 17 wherein the step of obtaining the spectrum is obtained over a predetermined period of time and said sample is stationary during said predetermined period of time.

22. A portable system for obtaining a spatially accurate wavelength-resolved image of a sample having a first and a second spatial dimension, comprising:

a photon emission source for sequentially illuminating a portion of said sample with a plurality of photons to thereby produce photons emitted by the sample wherein the photon emission source illuminates said sample along the first spatial dimension for each of plural predetermined positions of the second spatial dimension;

an optical lens for collecting the emitted photons and producing therefrom filtered photons;

a dispersive spectrometer for determining a wavelength of ones of the filtered photons; and

a photon detector for receiving the filtered photons and obtaining therefrom a spectrum of said sample.

23. The system of claim 22 wherein the photon emission source illuminates the sample along the first spatial dimension for each of plural predetermined positions of the second spatial dimension to thereby obtain plural spectra of said sample.

24. The system of claim 23 including a processor for producing a two dimensional image of said sample from the plural spectra.

25. The system of claim 22 wherein said photon detector is selected from the group consisting of:

charge-coupled device, complementary metal oxide semiconductor, charge injection device, intensified charge injection device, electron multiplying charge-coupled device, silicon photo diode, silicon avalanche diode, and focal plane array.

26. The system of claim 22 wherein said photon emission source is a laser.

27. The system of claim 22 wherein said photon emission source is a light emitting diode.

28. The system of claim 27 wherein said light emitting diode is disposed as a ring.

29. The system of claim 28 wherein said light emitting diode is a plurality of light emitting diodes.

30. The system of claim 27 wherein said light emitting diode is a plurality of light emitting diodes wherein one of said plural light emitting diodes emits photons at a wavelength that is different than a wavelength of photons emitted by another of said plural light emitting diodes.

31. The system of claim 30 wherein the wavelength of photons emitted by one of said plural light emitting diodes is in the ultraviolet wavelength range.

32. The system of claim 30 wherein the wavelength of photons emitted by one of said plural light emitting diodes is in the near infrared wavelength range.

33. The system of claim 22 wherein said spectrum is obtained over a predetermined period of time and said sample is stationary during said predetermined period of time.

34. The system of claim 22 wherein said spectrum is a Raman spectrum.

35. The system of claim 22 wherein the system is a hand-held system.

36. The system of claim 22 wherein said optical lens includes a laser rejection filter.

37. The system of claim 22 wherein said spectrum is a fluorescence spectrum.

38. The system of claim 22 wherein said spectrum is a near infrared spectrum.

39. A method for obtaining a spatially accurate wavelength-resolved image of a sample using a hand-held device, the method comprising the steps of:

providing a sample having a first and a second spatial dimension;

sequentially illuminating a portion of said sample with a plurality of photons from a photon emission source to thereby produce photons scattered by the sample the sequential illumination occurring along the first spatial dimension for each of plural predetermined positions of the second spatial dimension;

collecting the scattered photons and producing therefrom filtered photons;

determining a wavelength of ones of the filtered photons; and

receiving the filtered photons in a photon detector and obtaining therefrom a spectrum of said sample.

40. The method of claim 39 wherein the sample is illuminated along the first spatial dimension for each of plural predetermined positions of the second spatial dimension to thereby obtain plural spectra of said sample.

41. The method of claim 40 including the step of processing the spectra and producing therefrom a two dimensional image of said sample.

42. The method of claim 39 wherein the step of illuminating the sample is accomplished by illuminating the sample with plural light emitting diodes wherein one of said plural light emitting diodes emits photons at a wavelength that is different than a wavelength of photons emitted by another of said plural light emitting diodes.

43. The method of claim 42 wherein the wavelength of photons emitted by one of said plural light emitting diodes is in the ultraviolet wavelength range.

44. The method of claim 42 wherein the wavelength of photons emitted by one of said plural light emitting diodes is in the near infrared wavelength range.

45. The method of claim 39 wherein the step of obtaining the spectrum is obtained over a predetermined period of time and said sample is stationary during said predetermined period of time.