Multi-spectral optical method and system for detecting and classifying biological and non-biological particles

• US 7,106,442 B2
• Filed: 04/29/2004
• Issued: 09/12/2006
• Est. Priority Date: 04/29/2003
• Status: Active Grant

• Current Assignee: Teledyne FLIR Defense Incorporated (Teledyne Technologies Incorporated)
• Original Assignee: Alexander J. Fielding, David B. Silcott
• Inventors: Silcott, David B., Fielding, Alexander J.
• Primary Examiner(s): Stafira, Michael P.
• Application Number:
  US10/834,537
• Publication Number:
  US 20050243307A1
• Time in Patent Office: 866 Days
• Field of Search: None
• US Class Current: 356/338
• CPC Class Codes: G01N 1/2273 Atmospheric sampling
• CPC Class Codes: G01N 15/1434 Optical arrangements
• CPC Class Codes: G01N 15/1459 the analysis being performed on a sample stream
• CPC Class Codes: G01N 2001/022 sampling for security purposes, e.g. contraband, warfare agents
• CPC Class Codes: G01N 2001/2223 aerosol sampling devices
• CPC Class Codes: G01N 2015/1477 Multiparameters
• CPC Class Codes: G01N 2015/1493 Particle size

Abstract

Enhanced methods, apparatuses and systems are disclosed for the real-time detection and classification of biological and non-biological particles by substantially simultaneously measuring a single particle'"'"'s characteristics in terms of size and density, elastic scattering properties, and absorption and fluorescence.

Claims

1. A method for detecting and classifying a particle comprising the steps of:

providing and directing a sample stream containing particles to an optical viewing region;

providing a plurality of continuous wave excitation sources, each source emitting a discrete wavelength;

directing a plurality of discrete wavelengths of light from the continuous wave excitation sources to the optical viewing region;

illuminating each particle found in the sample stream in the viewing region with the excitation sources substantially simultaneously, said particle having elastic scattering properties, fluorescence or non-fluorescence emission properties, and dimension and density properties;

directing light from the viewing region to a plurality of detectors to produce a plurality of signals;

directing the signals from the detectors to a signal processor to substantially simultaneously measure the elastic scattering properties, the complex refractive index and the fluorescence or non-fluorescence of the particle substantially simultaneously and in substantially real time.

2. The method of claim 1, wherein the plurality of detectors comprises a plurality of detectors dedicated to detecting particle elastic scattering properties.

3. The method of claim 1, wherein the plurality of detectors comprises a plurality of detectors dedicated to detecting particle elastic scatter and at least one detector dedicated to detecting fluorescence.

4. The method of claim 1, wherein the plurality of continuous wave excitation sources are selected from the group consisting of lasers, light emitting diodes, and light emitting devices producing discrete particle excitation wavelength ranges.

5. The method of claim 4, wherein the lasers produce particle excitation ranges selected from the group consisting of from about 266 nm to about 300 nm;

about 350 nm to about 430 nm;

about 400 nm to about 430 nm and from about 600 nm to about 1500 nm.

6. The method of claim 4, wherein the excitation ranges are selected from the group consisting of from about 266 nm to about 280 nm, and from about 400 nm to about 415 nm, and from about 700 nm to about 1.5 μ

m.

7. The method of claim 1, wherein the particle is a biological particle.

8. The method of claim 7, wherein the biological particle comprises fluorophores or chromophores.

9. The method of claim 8, wherein the fluorophores are selected from the group consisting of amino acids, NADH, flavins and chlorophylls.

10. The method of claim 1, wherein the particle is a non-biological particle.

11. The method of claim 1, wherein at least two detectors are used to measure elastic scatter and complex refractive index and at least one detector is used to measure fluorescence.

12. The method of claim 1, wherein at least two detectors are used to measure elastic scatter and complex refractive index.

13. The method of claim 1, wherein the particle is inspected according to a dimensional feature space greater than or equal to a seven dimensional feature space.

14. The method of claim 4, wherein the continuous wave excitation sources comprise three lasers.

15. The method of claim 4, wherein the continuous wave excitation sources comprise two lasers.

16. The method of claim 1, wherein the particle is airborne.

19. The method of claim 1, wherein the laser produces a plurality of excitation wavelengths, at least one excitation wavelength of which operates in a continuous manner to provide a triggering mechanism for a detection mode.

20. The method of claim 1, wherein each excitation source provides a different excitation wavelength, with each wavelength is optically aligned along the same axis orthogonal to an optical viewing region.

21. The method of claim 1, wherein each excitation source provides three different excitation wavelengths, with two of the wavelengths aligned along the same axis orthogonal to a particle detection space, and with the third wavelength separated at a defined distance from the other two wavelengths.

22. The method of claim 1, wherein each excitation source provides three different excitation wavelength, with all three wavelengths separated from each other at a defined distance.

23. The method of claim 1, wherein each excitation source provides two different excitation wavelengths, with one of the two wavelengths aligned along the same axis orthogonal to a particle detection space, and with one of the two wavelengths separated at a defined distance from the other wavelengths.

24. The method of claim 4, wherein the excitation source produces a beam conditioned to have line thickness of from about 5 to about 300 microns.

25. The method of claim 1, further comprising the steps of:

directing a sample of air to the optical viewing region from an environment selected from the group consisting of an exterior environment and an interior environment.

26. The method of claim 1, further comprising the steps of:

directing a sample of air to the optical viewing region from an environment selected from the group consisting of;

a battlefield, a hospital, a mailroom, an industrial facility, a vehicle compartment;

a building interior, and an air stream with and without communication with an HVAC system.

57. A system for detecting biological and non-biological particles comprising the apparatus of claim 26.

17. A method for detecting and classifying a particle comprising the steps of:

providing and directing a sample stream containing particles to an optical viewing region;

providing a continuous wave excitation sources, said continuous wave source emitting a discrete wavelength;

providing a pulsed wave excitation source, said pulsed wave excitation source emitting a discrete wavelength;

providing at least one nonlinear crystal for generating second and third harmonic wavelength generation;

directing a plurality of discrete wavelengths of light from the continuous wave excitation source and the pulsed wave excitation source to the optical viewing region;

illuminating each particle found in the sample stream in the viewing region with the excitation sources substantially simultaneously, said particle having elastic scattering properties, fluorescence or non-fluorescence emission properties, and dimension and density properties;

directing light from the viewing region to a plurality of detectors to produce a plurality of signals;

directing the signals from the detectors to a signal processor to substantially simultaneously measure the elastic scattering properties, the complex refractive index and the fluorescence or non-fluorescence of the particle substantially simultaneously in substantially real time.

18. The method of claim 17, wherein three detectors are used to measure elastic scatter and complex refractive index and at least one detector is used to measure fluorescence.

27. The method of claim 17, wherein the particle is airborne.

28. An apparatus for detecting and classifying a single particle from a sample comprising:

a plurality of continuous wave excitation sources, each source emitting a discrete wavelength, the wavelengths directed through an optical viewing region;

a plurality of detectors to receive the wavelengths directed through the optical viewing region and produce a plurality of signals; and

a signal processor in communication with each detector to receive the signal from the detector to substantially simultaneously measure the elastic scattering properties, the complex refractive index and the fluorescence or non-fluorescence of the particle substantially simultaneously and in substantially real-time.

29. The apparatus of claim 28, wherein the plurality of detectors comprises a plurality of detectors dedicated to detecting particle elastic scattering properties.

30. The apparatus of claim 28, wherein the plurality of detectors comprises a plurality of detectors dedicated to detecting particle elastic scatter and at least one detector dedicated to detecting particle fluorescence.

31. The apparatus of claim 28, wherein the plurality of continuous wave excitation sources are selected from the group consisting of lasers, light emitting diodes, and light emitting devices producing discrete particle excitation wavelength ranges.

32. The apparatus of claim 31, wherein the lasers produce particle excitation ranges selected from the group consisting of from about 266 nm to about 300 nm;

about 350 nm to about 430 nm;

about 400 nm to about 430 nm; and

from about 600 nm to about 1500 nm.

33. The apparatus of claim 28, wherein the particle is a biological particle.

34. The apparatus of claim 33, wherein the biological particle comprises fluorophores or chromophores.

35. The apparatus of claim 34, wherein the fluorophores are selected from the group consisting of amino acids, NADH, flavins and chlorophylls.

36. The apparatus of claim 28, wherein the particle is a non-biological particle.

37. The apparatus of claim 28, wherein at least two detectors are used to measure elastic scatter and complex refractive index and at least one detector is used to measure fluorescence.

38. The apparatus of claim 28, wherein at least two detectors are used to substantially simultaneously measure elastic scatter and complex refractive index.

39. The apparatus of claim 28, wherein the particle is inspected according to a dimensional feature space greater than or equal to a seven dimensional feature space.

40. The apparatus of claim 28, wherein the continuous wave excitation sources comprise three lasers.

41. The apparatus of claim 28, wherein the continuous wave excitation sources comprise two lasers.

42. The apparatus of claim 28, wherein the excitation source produces a beam conditioned to have a line thickness of from about 5 to about 300 microns.

43. The apparatus of claim 28, wherein the particle is airborne.

53. A vehicle comprising the apparatus of claim 28.

55. A building comprising the apparatus of claim 28.

58. A system for detecting biological and non-biological particles comprising the apparatus of claim 41.

44. An apparatus for detecting and classifying a single particle from a sample comprising:

a continuous wave excitation sources, said continuous wave excitation source emitting a discrete wavelength, the wavelength directed through an optical viewing region;

a pulsed wave excitation source, said pulsed wave excitation source emitting a discrete wavelength;

at least one nonlinear crystal for generating second and thirds harmonic wavelengths;

a plurality of detectors to receive the wavelengths directed through the optical viewing region and produce a plurality of signals; and

a signal processor in communication with each detector to receive the signal from the detector to substantially simultaneously measure the elastic scattering properties, the complex refractive index and the fluorescence or non-fluorescence of the particle substantially simultaneously and in substantially real time.

45. The apparatus of claim 44, wherein three detectors are used to measure elastic scatter and complex refractive index and at least one detector is used to measure fluorescence.

46. The apparatus of claim 44, wherein the continuous wave laser operates in a continuous manner to provide a triggering mechanism for a detection mode.

47. The apparatus of claim 44, wherein each excitation source provides a different excitation wavelength, with each wavelength optically aligned along the same axis orthogonal to an optical viewing region.

48. The apparatus of claim 44, wherein each excitation source provides three different excitation wavelength, with two of the wavelengths aligned along the same axis orthogonal to a particle detection space, and with the third wavelength separated at a defined distance from the other two wavelengths.

49. The apparatus of claim 44, wherein each excitation source provides three different excitation wavelength, with all three wavelengths optically aligned with all three wavelengths separated from each other at a defined distance.

50. The apparatus of claim 44, wherein each excitation source provides two different excitation wavelength, with one of the two wavelengths aligned along the same axis orthogonal to a particle detection space, and with one of the two wavelength separated at a defined distance from the other wavelength.

51. The apparatus of claim 44, wherein the excitation source produces a beam conditioned to have a line thickness of from about 5 to about 300 microns.

52. The apparatus of claim 44, further comprising detectors for detecting fluorescence having a wide angle collection configuration of about 4π

steradians.

54. A vehicle comprising the apparatus of claim 44.

56. A building comprising the apparatus of claim 44.