System and method for detecting and identifying an analyte

• US 20050207943A1
• Filed: 03/22/2005
• Published: 09/22/2005
• Est. Priority Date: 03/22/2004
• Status: Active Grant

• Current Assignee: Quantaspec Incorporated
• Original Assignee: Quantaspec Incorporated
• Inventors: Puzey, Kenneth A.
• Granted Patent: US 7,623,234 B2
• Time in Patent Office: Days
• US Class Current: 422/82.50
• CPC Class Codes: C12Q 1/04 Determining presence or kind of microorganism; Use of selective media for testing antibiotics or bacteriocides; Compositions containing a chemical indicator therefor C12Q1/6897 takes precedence
• CPC Class Codes: G01N 2021/1793 Remote sensing
• CPC Class Codes: G01N 2021/3137 with selection of wavelengths after the sample
• CPC Class Codes: G01N 2021/3166 using separate detectors and filters
• CPC Class Codes: G01N 2021/3513 Open path with an instrumental source
• CPC Class Codes: G01N 2021/4707 Forward scatter; Low angle scatter
• CPC Class Codes: G01N 2021/4709 Backscatter
• CPC Class Codes: G01N 2021/4728 Optical definition of scattering volume
• CPC Class Codes: G01N 21/31 Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry G01N21/72 takes precedence
• CPC Class Codes: G01N 21/3504 for analysing gases, e.g. multi-gas analysis
• CPC Class Codes: G01N 21/53 within a flowing fluid, e.g. smoke

Abstract

A sensor (200, 900) comprising an illuminator (212, 500, 804, 832, 858, 904), a receiver (216, 400, 420, 460, 480, 808, 836, 862, 924) and an analyzer (240) for detecting and identifying an analyte having a characteristic absorption band that is present in a sample region (208, 812, 824, 874, 922). The illuminator includes an illumination source (220) for illuminating the sample region with spectral energy across at least a portion of the characteristic absorption band. The receiver includes a detector (228, 404, 424, 460, 484, 866, 928) for sensing predetermined portions of the spectral energy band and for creating a sample spectral data vector (236). The analyzer uses the spectral data vector and known characteristic data to detect and identify the analyte.

Claims

1. A system for detecting an analyte having a characteristic absorption band, comprising:

a) an illuminator operatively configured to emit a spectral energy band across at least a portion of the characteristic absorption band of the analyte; and

b) a receiver operatively configured to selectively sense a plurality of predetermined sub-bands of said spectral energy band simultaneously.

2. A system according to claim 1, wherein said illuminator comprises a QC laser.

3. A system according to claim 2, wherein said QC laser is a Faby-Perot QC laser.

4. A system according to claim 1, wherein said receiver comprises:

a) a broadband detector array having a plurality of detecting regions; and

b) a filter in operative relationship with said detecor array so that each of said plurality of sensing regions receives a corresponding respective one of said plurality of predetermined sub-bands of said spectral energy band.

5. A system according to claim 4, wherein said filter comprises a linear variable interference filter.

6. A system according to claim 5, wherein said linear variable interference filter is applied to said broadband sensor array.

7. A system according to claim 4, wherein said filter comprises a diffraction grating.

8. A system according to claim 4, wherein said filter comprises a tunable filter.

9. A system according to claim 8, wherein said tunable filter is a stacked electro-optic tunable filter.

10. A system according to claim 8, wherein said tunable filter is applied to said broadband sensor array.

11. A system according to claim 1, wherein said receiver comprises a plurality of narrowband detectors each operatively configured to sense a corresponding respective one of said plurality of predetermined sub-bands of said spectral energy band.

12. A system according to claim 1, further comprising an analyzer operatively coupled to said receiver, said analyzer operatively configured to identify the analyte.

13. A system according to claim 12, wherein said analyzer is operatively configured to identify the analyte using a canonical vector analysis.

14. A system according to claim 12, wherein said analyzer is operatively configured to identify the analyte using least squares fit to known spectra.

15. A system according to claim 12, wherein the analyte comprises a plurality of particles and said analyzer is operatively configured to determine the size of the plurality of particles.

16. A system according to claim 15, wherein said analyzer is operatively configured to determine the size of the plurality of particles based on Rayleigh scattering.

17. A system according to claim 1, further comprising a communications device for communicating with at least one of the following:

a like system and a remote computer.

18. A method of detecting and identifying an analyte having a characteristic absorption band, comprising the steps of:

a) illuminating a region suspected of containing the analyte with a spectral energy band across at least a portion of the characteristic absorption band of the analyte; and

b) selectively sensing a plurality of predetermined portions of said spectral energy band simultaneously so as to create sample data.

19. A method according to claim 18, further comprising the step of generating a sample spectral data vector from said sample data.

20. A method according to claim 19, further comprising the step of analyzing said sample data vector relative to data for known groups of analyte.

21. A method of identifying bacteria present in a sample and belonging to a bacterial species, comprising the steps of:

a) collecting spectral data regarding a sample using a detector at a range of greater than two meters; and

b) determining the bacterial species of the bacteria as a function of said spectral data.

22. A method according to claim 21, wherein the spectral data comprises a plurality of spectral data points and step a) includes collecting said spectral data points simultaneously with one another.

23. A method according to claim 21, wherein step a) comprises illuminating the sample using a QC laser.