DEVICE FOR EVALUATION OF FLUIDS USING ELECTROMAGNETIC ENERGY

• US 20140233015A1
• Filed: 03/12/2013
• Published: 08/21/2014
• Est. Priority Date: 02/21/2013
• Status: Active Grant

• Current Assignee: Visualant, Inc.
• Original Assignee: Visualant, Inc.
• Inventors: Mander, Richard Ian, Beach, Allan David, Denton, Michael Vivian, Tompkins, Alan Charles, Furness, Tom A. III
• Granted Patent: US 9,041,920 B2
• Time in Patent Office: Days
• US Class Current: 356/51
• CPC Class Codes: G01N 21/01 Arrangements or apparatus for facilitating the optical investigation
• CPC Class Codes: G01N 21/0303 Optical path conditioning in cuvettes, e.g. windows; adapted optical elements or systems; path modifying or adjustment G01N21/031 - G01N21/15 take precedence
• CPC Class Codes: G01N 21/05 Flow-through cuvettes G01N21/09 takes precedence; handling fluid samples G01N1/10
• CPC Class Codes: G01N 21/49 within a body or fluid
• CPC Class Codes: G01N 21/59 Transmissivity G01N21/25 takes precedence
• CPC Class Codes: G01N 2201/022 Casings
• CPC Class Codes: G01N 2201/06113 Coherent sources; lasers

Abstract

A portable, tabletop fluid sampling device simplifies spectral analysis to produce an accurate but inexpensive chromatic fingerprint for fluid samples. In one embodiment, the sampling device uses an array of variable wavelength LED emitters and photodiode detectors to measure Rayleigh scattering of electromagnetic energy from the fluid sample contained in a cuvette. Either the fluid itself, or particles suspended in the fluid can then be identified by performing spectral pattern matching to compare results of a spectral scan against a library of known spectra. A wide range of applications include substance identification, security screening, authentication, quality control, and medical diagnostics.

Claims

1. A sampling device, comprising:

a housing;

a sample chamber in the housing, the sample chamber sized and dimensioned to receive a sample cuvette at least partially therein, the sample chamber having at least one opaque wall and at least a first aperture and a second aperture positioned at least partially across at least a portion of the sample chamber from the first aperture, the first and the second aperture transmissive of electromagnetic energy of at least some wavelengths in an optical portion of the electromagnetic spectrum;

a plurality of emitters received in the housing, each of the emitters selectively operable to emit electromagnetic energy in a respective range of wavelengths toward and through the first aperture of the sample chamber, the ranges of wavelengths of at least some of the emitters different from the ranges of wavelengths of others of the emitters;

at least one primary sampling sensor positioned to receive electromagnetic energy emitting from the sample chamber via the second aperture; and

at least one calibration sensor positioned to receive electromagnetic energy emitted by at least one of the emitters, substantially free of electromagnetic energy emitting, if any, from the sample chamber.

2. The sampling device of claim 1 further comprising a calibration printed circuit board (PCBA) having a slit opposed to the emitters, and the at least one calibration sensor includes at least a first calibration sensor positioned to one side of the slit and at least a second calibration sensor positioned to another side of the slit, the other side of the slit disposed across the slit from the first side of the slit.

3. The sampling device of claim 2 wherein the emitters are all aligned with the slit.

4. The sampling device of claim 1 wherein the at least one calibration sensor is positioned at least adjacent a first portion of the sample chamber opposed to the emitters.

5. The sampling device of claim 3 wherein the emitters are carried by an emitter circuit board, the emitter circuit board spaced from the sample chamber opposed to the first aperture.

6. The sampling device of claim 5 wherein at least one of the primary sampling sensors is carried by a direct sensor circuit board, the direct sensor circuit board spaced from the sample chamber opposed to the second aperture.

7. The sampling device of claim 1 wherein the sample chamber includes a third aperture, the third aperture positioned at least partially across the sampling chamber from both the first and the second apertures, and the at least one primary sampling sensor includes at least a first primary sampling sensor positioned to receive electromagnetic energy emitting from the sampling chamber via the second aperture and at least a second primary sampling sensor positioned to receive electromagnetic energy emitting from the sampling chamber via the third aperture.

8. The sampling device of claim 7 wherein the second aperture is diametrically opposed across the sample chamber from the first aperture and the third aperture is non-collinear with an optical axis that extends between the first and the second apertures.

9. The sampling device of claim 8 wherein the third aperture is positioned along an axis perpendicular to the optical axis that extends between the first and the second apertures.

10. The sampling device of claim 7 wherein the emitters are carried by an emitter circuit board, the emitter circuit board spaced from the sample chamber opposed to the first aperture, at least the first primary sampling sensors are carried by a direct sensor circuit board, the direct sensor circuit board spaced from the sample chamber opposed to the second aperture, and at least the second primary sampling sensors are carried by an indirect sensor circuit board, the indirect sensor circuit board spaced from the sample chamber opposed to the third aperture to capture electromagnetic energy scattered from the sample chamber.

11. The sampling device of claim 1, further comprising:

a biasing member that biases at least the sample cuvette outwardly from the housing.

12. The sampling device of claim 1 wherein the respective ranges of wavelengths of at least two of the emitters at least partially overlap.

13. The sampling device of claim 1, further comprising:

the sample cuvette sized and dimensioned to be at least partially received by the sample chamber, at least a portion of the sample cuvette transmissive to at least some of the wavelengths of electromagnetic energy emitted by the emitters.

14. The sampling device of claim 1 wherein the optical portion of the electromagnetic spectrum extends from near-infrared through near-ultraviolet.

15. The sampling device of claim 1, further comprising:

at least one port providing flow through fluid communication with the cuvette.

16. The sampling device of claim 1, further comprising:

at least one control subsystem communicatively coupled to the emitters, the primary sampling sensors; and

the calibration sensors; and

at least one temperature sensor communicatively coupled to the at least one control subsystem, wherein the at least one control subsystem controls operation based at least in part on information from both the calibration sensors and the at least one temperature sensor.

17. The sampling device of claim 16 wherein the at least one control subsystem calibrates an output value based at least in part on information from both the calibration sensors and the at least one temperature sensor.

18. The sampling device of claim 16 wherein the at least one control subsystem calibrates a drive signal supplied to at least one of the emitters based at least in part on information from both the calibration sensors and the at least one temperature sensor.

19. A sampling device, comprising:

a housing;

a sample chamber in the housing, the sample chamber sized and dimensioned to receive a sample cuvette at least partially therein, the sample chamber having at least one opaque wall and at least a first aperture, a second aperture positioned at least partially across at least a portion of the sample chamber from the first aperture, and a third aperture, the third aperture positioned at least partially across the sampling chamber from both the first and the second apertures, the first, the second, and the third apertures transmissive of electromagnetic energy of at least some wavelengths in an optical portion of the electromagnetic spectrum;

a plurality of emitters received in the housing, each of the emitters selectively operable to emit electromagnetic energy in a respective range of wavelengths toward and through the first aperture of the sample chamber, the ranges of wavelengths of at least some of the emitters different from the ranges of wavelengths of others of the emitters;

at least one direct primary sampling sensor positioned to receive electromagnetic energy emitting from the sampling chamber via the second aperture and not by the first or the third apertures; and

at least one indirect primary sampling sensor positioned to receive electromagnetic energy emitting from the sampling chamber via the third aperture and not by the first or the second apertures.

20. The sampling device of claim 19 wherein the second aperture is diametrically opposed across the sample chamber from the first aperture.

21. The sampling device of claim 20 wherein the third aperture is non-collinear with an optical axis that extends between the first and the second apertures.

22. The sampling device of claim 20 wherein the third aperture is perpendicular to an optical axis that extends between the first and the second apertures.

23. The sampling device of claim 19 wherein the emitters are carried by an emitter circuit board, the emitter circuit board spaced from the sample chamber opposed to the first aperture, at least the first primary sampling sensor is carried by a direct sensor circuit board, the direct sensor circuit board spaced from the sample chamber opposed to the second aperture, and at least the second primary sampling sensors is carried by an indirect sensor circuit board, the indirect sensor circuit board spaced from the sample chamber opposed to the third aperture to capture electromagnetic energy scattered from the sample chamber.

24. The sampling device of claim 19, further comprising:

at least one calibration sensor positioned to receive electromagnetic energy emitted by at least one of the emitters, substantially free of electromagnetic energy emitting, if any, from the sampling chamber.

25. The sampling device of claim 24, further comprising:

at least one control subsystem communicatively coupled to the emitters, the primary sampling sensors; and

the calibration sensors; and

at least one temperature sensor communicatively coupled to the at least one control subsystem, wherein the at least one control subsystem controls operation based at least in part on information from both the calibration sensors and the at least one temperature sensor.

26. The sampling device of claim 25 wherein the at least one control subsystem calibrates an output value based at least in part on information from both the calibration sensors and the at least one temperature sensor.

27. The sampling device of claim 19, further comprising:

a biasing member that biases at least the sample cuvette outwardly from the housing.

28. The sampling device of claim 19 wherein the respective range of wavelengths of at least two of the emitters at least partially overlap.

29. The sampling device of claim 19, further comprising:

the sample cuvette sized and dimensioned to be at least partially received by the sample chamber, at least a portion of the sample cuvette transmissive to at least some of the wavelengths of electromagnetic energy emitted by the emitters.

30. The sampling device of claim 19 wherein the optical portion of the electromagnetic spectrum extends from near-infrared through near-ultraviolet.

31. The sampling device of claim 19, further comprising:

at least one port providing flow through fluid communication with the cuvette.

32. The sampling device of claim 22 wherein a change in electromagnetic energy intensity emitting from the sampling chamber via the third aperture is indicative of a time-varying process occurring in the sample.