Method and apparatus for interactive hyperspectral image subtraction

1. A method of obtaining a spectral image of each of a plurality of predetermined chemical species in a sample, comprising:

(a) illuminating said sample with a first plurality of photons to produce a second plurality of photons;

(b) collecting said second plurality of photons and producing a plurality of images of said sample therefrom each of said images comprising a frame consisting essentially of a plurality of pixels;

(c) for each of said plurality of predetermined chemical species, identifying at least one wavelength range at which said chemical specie exhibits a unique absorption of radiation;

(d) identifying at least one wavelength range at which none of said plurality of predetermined chemical species exhibits an absorption of radiation;

(e) in each of said image frames, identifying which of said plurality of pixels do not contain any of said plurality of predetermined chemical species;

(f) in each of said image frames, identifying which of said plurality of pixels contain only a first of said plurality of predetermined chemical species;

(g) repeating said step (f) for each of said plurality of predetermined chemical species;

(h) in each of said image frames, identifying which of said plurality of pixels contain more than one of said plurality of predetermined chemical species;

(i) for each of said plurality of pixels that contains more than one of said plurality of predetermined chemical species, separating the contribution of each of said predetermined chemical species; and

(j) composing separate spectral images of each of said plurality of predetermined chemical species in said sample.

2. The method according to claim 1 , wherein said wavelength range is in the near IR range.

3. The method according to claim 1 , wherein said wavelength range is in the visible range.

4. The method according to claim 1 , wherein said wavelength range is in the near UV range.

5. The method according to claim 1 , wherein said step (a) comprises illuminating a predetermined area of said sample with substantially monochromatic light.

6. The method according to claim 1 , wherein said second plurality of photons are passed through at least one filter.

7. The method according to claim 6 , wherein said at least one filter is selected from the group consisting of a tunable filter, a band pass filter, a liquid crystal tunable filter, an interferometer, an acousto optical tunable filter, a dispersive optical device and a computed tomography imaging spectrometer.

8. The method according to claim 1 , wherein said spectral image is a spatially accurate wavelength resolved image.

9. The method according to claim 5 , wherein said monochromatic light has a wavelength within the range of 500 nm to 800 nm.

10. The method according to claim 9 , wherein said monochromatic light is produced using a laser.

11. An apparatus for obtaining a spectral image of each of a plurality of predetermined chemical species in a sample, comprising:

(a) an illumination source for illuminating said sample with a first plurality of photons to form a second plurality of photons;

(b) an optical device for receiving and directing said second plurality of photons to an imaging device;

(c) an imaging device for forming a plurality of images of said sample, each of said images comprising a frame consisting essentially of a plurality of pixels; and

(d) a processor in communication with said imaging device, said processor being adapted to:

(i) for each of said plurality of predetermined chemical species, identifying at least one wavelength range at which said chemical specie exhibits a unique absorption of radiation;

(ii) identifying at least one wavelength range at which none of said plurality of predetermined chemical species exhibits an absorption of radiation;

(iii) in each of said image frames, identifying which of said plurality of pixels do not contain any of said plurality of predetermined chemical species;

(iv) in each of said image frames, identifying which of said plurality of pixels contain only a first of said plurality of predetermined chemical species;

(v) repeating said step (iv) for each of said plurality of predetermined chemical species;

(vi) in each of said image frames, identifying which of said plurality of pixels contain more than one of said plurality of predetermined chemical species;

(vii) for each of said plurality of pixels that contains more than one of said plurality of predetermined chemical species, separating the contribution of each of said predetermined chemical species; and

(viii) composing separate spectral images of each of said plurality of predetermined chemical species in said sample.

12. The apparatus according to claim 11 , wherein said wavelength range is in the near IR range.

13. The apparatus according to claim 11 , wherein said wavelength range is in the visible range.

14. The apparatus according to claim 11 , wherein said wavelength range is in the near UV range.

15. The apparatus according to claim 11 , wherein said illumination source produces substantially monochromatic light.

16. The apparatus according to claim 11 , wherein said optical device comprises at least one filter.

17. The apparatus according to claim 16 , wherein said at least one filter is selected from the group consisting of a tunable filter, a band pass filter, a liquid crystal tunable filter, an interferometer, an acousto optical tunable filter, a dispersive optical device and a computed tomography imaging spectrometer.

18. The apparatus according to claim 11 , wherein said spectral image is a spatially accurate wavelength resolved image.

19. The apparatus according to claim 15 , wherein said monochromatic light has a wavelength within the range of 500 nm to 800 nm.

20. The apparatus according to claim 19 , wherein said illumination source is a laser.