System, method, and apparatus for non-intrusively determining concentration of a solute in a solution

• US 6,831,746 B2
• Filed: 05/30/2002
• Issued: 12/14/2004
• Est. Priority Date: 05/30/2001
• Status: Expired due to Fees

• Current Assignee: Sciperio, Inc., Techtrol, Inc.
• Original Assignee: Sciperio, Inc.
• Inventors: Church, Kenneth H., Ardrey, William, Cassidy, Christopher S., Teague, Keith
• Primary Examiner(s): Toatley, Jr., Gregory J.
• Assistant Examiner(s): Nguyen, Sang H.
• Application Number:
  US10/161,079
• Publication Number:
  US 20030107012A1
• Time in Patent Office: 929 Days
• Field of Search: 356/432-442, 356/246, 356/300, 356/39-42, 250/372-373, 600/310-323, 600/473, 600/476, 128/633, 128/665
• US Class Current: 356/437
• CPC Class Codes: G01N 21/01 Arrangements or apparatus for facilitating the optical investigation
• CPC Class Codes: G01N 21/031 Multipass arrangements
• 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 21/33 using ultraviolet light G01N21/39 takes precedence
• CPC Class Codes: G01N 33/182 specific anions in water electrochemical analysis G01N27/26; detection of ions by colorimetry G01N31/22

Abstract

Concentration of a solute in a solution is determined. Light from a light source is received at a chamber containing the solute and the solution. The light is transmitted along an optical path length of the chamber, through the solute and the solution, and output from the chamber. The light output from the chamber is detected by a detector. The optical path length of the chamber is selected to optimize sensitivity of the detector. The concentration of the solute in the solution is determined based on the light received by the detector.

Claims

1. A system for determining concentration of a solute in a solution, the system comprising:

an optical source for providing light in a predetermined wavelength range;

a chamber for containing the solute in the solution, the chamber having an input for receiving the light, an optical path length along which the light is transmitted through the solute and the solution in the chamber, and an output for outputting the light transmitted through the chamber;

a detector for receiving light transmitted along the optical path length of the chamber to the output of the chamber, wherein the optical path length of the chamber is selected to optimize sensitivity of the detector; and

an analyzer for determining the concentration of the solute in the solution based on the light received by the detector,

wherein the optical path length of the chamber is related to the sensitivity of the detector by the equations;

2. The system of claim 1, wherein the optical path length of the chamber is

selected to provide an adequate intensity of light to the detector.

3. The system of claim 1, wherein the optical path length of the chamber is selected to provide an adequate resolution for the detector.

4. The system of claim 1, wherein the analyzer analyzes the spectral distribution of the received light and determines the concentration of the solute within the solution based on the spectral distribution.

5. The system of claim 1, wherein the detector includes an array of detectors.

6. The system of claim 1, wherein the detector determines based on a signature of the received light the concentration of the solute.

7. The system of claim 6, wherein the signature includes at least one peak absorption wavelength, and the detector includes a detector for each peak absorption wavelength.

8. The system of claim 1, wherein the detector includes a wavelength selective optics and photosensitive elements, and the analyzer analyzes the light detected by the photosensitive elements to determine the concentration of the solute in the solution.

9. The system of claim 8, wherein the wavelength selective optics include a diffraction grating.

10. The system of claim 8, wherein the wavelength selective optics include filters.

11. The system of claim 8, wherein the photosensitive elements include photosensitive diodes.

12. The system of claim 1, wherein the solute is chlorine, and the solution is chlorine in water.

13. The system of claim 1, wherein the chamber includes an input for the solution filling the chamber and output for outputting the solution.

14. The system of claim 13, wherein the flow of solution in and out of volume is controlled.

15. The system of claim 1, further comprising an analog and digital signal processing for comparing the received light of the detector with a reference signal.

16. The system of claim 15, wherein the reference signal is fed directly from the optical source to the detector.

17. The system of claim 15, wherein the analog and digital signal processing subtracts the reference signal from the detected signal to eliminate noise.

18. The system of claim 1, wherein the concentration of solute in the solution is determined in real time.

19. The system of claim 1, wherein the optical light source includes a controlled flashing light source.

20. The system of claim 1, wherein the detector sensitivity is in the parts per million (ppm) range.

21. A method for determining concentration of a solute in a solution, the method system comprising:

receiving light in a predetermined wavelength range from a light source at a chamber including the solute in the solution;

transmitting the received light along an optical path length of the chamber, through the solute in the solution in the chamber;

outputting the transmitted light from the chamber;

detecting the output light, wherein the optical path length of the chamber is selected to optimize sensitivity of the detection; and

determining the concentration of the solute in the solution based on the light received by the detector,

wherein the step of detecting is performed by wavelength selective optics and photosensitive elements, wherein the step of determining includes analyzing the light detected by the photosensitive elements to determine the concentration of the solute in the solution, wherein the photosensitive elements include photosensitive diodes, and wherein the optical path length of the chamber is related to the sensitivity of the detector by the equations;

22. The method of claim 21, wherein the optical path length of the chamber is selected to provide an adequate intensity of light to the detector.

23. The method of claim 21, wherein the optical path length of the chamber is selected to provide an adequate resolution for the detector.

24. The method of claim 21, wherein the step of determining includes analyzing the spectral distribution of the received light and determining the concentration of the solute within the solution based on the spectral distribution.

25. The method of claim 21, wherein the step of detecting is performed by an array of detectors.

26. The method of claim 21, wherein the step of determining included determines based on a signature of the received light the concentration of the solute.

27. The method of claim 26, wherein the signature includes at least one peak absorption wavelength, and the step of detecting includes detecting each peak absorption wavelength.

28. The method of claim 21, wherein the wavelength selective optics include a diffraction grating.

29. The method of claim 21, wherein the wavelength selective optics include filters.

30. The method of claim 21, wherein the solute is chlorine, and the solution includes chlorine in water.

31. The method of claim 21, wherein the chamber includes an input for the solution filling the chamber and output for outputting the solution.

32. The method of claim 31, wherein the flow of solution in and out of volume is controlled.

33. The method of claim 21, further comprising comparing the received light with a reference signal.

34. The method of claim 33, wherein the reference signal is fed directly from the optical source to the detector.

35. The method of claim 33, wherein the step of comparing comprises subtracting the reference signal from the detected signal to eliminate noise.

36. The method of claim 21, wherein the steps are performed in real time.

37. The method of claim 21, wherein the optical light source includes a controlled flashing light source.

38. The method of claim 21, wherein the detector sensitivity is in the parts per million (ppm) range.

39. An apparatus containing a solute in a solution, the apparatus comprising:

a volume for containing the solute in the solution;

an input for receiving light in a predetermined wavelength range from a light source;

an optical path length along which the light is transmitted through the solute in the solution in the chamber; and

an output for outputting the light transmitted along the optical path length, wherein the output light is received at a detector and analyzed to determined the concentration of the solute in the solution, and the optical path length of the chamber is selected to optimize sensitivity of the detector, and wherein the optical path length of the chamber is related to the sensitivity of the detector by the equations;

40. The apparatus of claim 39, wherein the optical path length is selected to provide an adequate intensity of light to the detector.

41. The apparatus of claim 39, wherein the optical path length is selected to provide an adequate resolution for the detector.

42. The apparatus of claim 39, wherein the spectral distribution of the output light is analyzed to determine the concentration of the solute within the solution based on the spectral distribution.

43. The apparatus of claim 39, wherein the output light is detected by an array of detectors.

44. The apparatus of claim 39, wherein the concentration of the solute is determined based on a signature of the received light the concentration of the solute.

45. The apparatus of claim 44, wherein the signature includes at least one peak absorption wavelength, and the output light is detected by a detector for each peak absorption wavelength.

46. The apparatus of claim 39, wherein the output light is detected by selective optics and photosensitive elements.

47. The apparatus of claim 46, wherein the wavelength selective optics include a diffraction grating.

48. The apparatus of claim 46, wherein the wavelength selective optics include filters.

49. The apparatus of claim 46, wherein the photosensitive elements include photosensitive diodes.

50. The apparatus of claim 39, wherein the solute is chlorine, and the solution includes chlorine in water.

51. The apparatus of claim 39, further comprising an input for the solution filling the volume and an output for outputting the solution.

52. The apparatus of claim 39, wherein the output light is compared with a reference signal.

53. The apparatus of claim 52, wherein the reference signal is fed directly from the optical source to the detector.

54. The apparatus of claim 53, wherein the reference signal is subtracted from the detected signal to eliminate noise.

55. The apparatus of claim 39, wherein the concentration of solute in the solution is determined in real time.

56. The apparatus of claim 39, wherein the input light is provide by a controlled flashing light source.

57. The apparatus of claim 51, wherein the flow of solution in and out of volume is controlled.

58. The apparatus of claim 39, wherein the detector sensitivity is in the parts per million (ppm) range.