System of fluid inspection and/or identification

• US 5,002,397 A
• Filed: 10/16/1989
• Issued: 03/26/1991
• Est. Priority Date: 04/13/1988
• Status: Expired due to Fees

• Current Assignee: International Automated Systems
• Original Assignee: International Automated Systems
• Inventors: Modlin, Douglas, Littlejohn, Douglas J., Ingrum, Jerry G.
• Primary Examiner(s): McGraw, Vincent P.
• Application Number:
  US07/421,263
• Time in Patent Office: 526 Days
• Field of Search: 356/240, 356/407, 356/409, 356/410, 356/411, 356/414, 250/223 B, 250/226, 209/524, 209/581, 209/582, 364/498
• US Class Current: 356/407
• CPC Class Codes: G01N 2021/3196 Correlating located peaks in spectrum with reference data, e.g. fingerprint data
• 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 21/85 Investigating moving fluids or granular solids
• CPC Class Codes: G01N 21/94 Investigating contamination, e.g. dust G01N21/85 takes precedence

Abstract

A Method and Apparatus for identifying and distinguishing fluids and for recognizing contamination of a fluid, which method and apparatus utilizes spectrographic analysis of control samples of known fluids and then spectrographic analysis of unknown fluids to generate optical signatures, finger prints and/or profiles of data and processed data relating to the relative intensities of light at selected wavelengths; and then, through comparison of the various signatures, fingerprints and/or profiles, provides determinative information as to contamination or non-contamination of the unknown fluids; after which appropriate operation control is effected and/or exercised.

Claims

1. Fluid inspection method, comprising the steps of:

a. creating a control sample defining a known fluid, wherein the known fluid is a solution of a known non-contaminant and a known liquid in known concentrations;

b. directing light from a light source at the control sample;

c. collecting light after absorption of at least some of the light by the control sample;

d. separating the collected light from the control sample into a plurality of pre-selected wavelengths;

e. detecting the relative intensity of the collected light at each of the pre-selected wavelengths;

f. collecting data associated with the control sample indicating, at least, relative intensities of the collected light at each of the preselected wavelengths;

g. creating a modified control sample defining the known fluid modified as to one or both of the properties;

(i) the concentration level of non-contaminant in solution; and

/or (ii) the temperature of the control sample;

h. repeating, for the modified control sample, the steps of directing light, collecting light, separating, detecting, collecting data, and creating a modified control sample; and

i. processing the collected data to provide processed control data representative of a plurality of mathematical inter-relationships among the relative intensity data associated with the pre-selected wavelengths of each control sample;

j. correlating the data of all control samples to provide at least a first "signature" which represents the known non-contaminant;

k. directing light from a light source at a fluid to be tested;

l. collecting light after absorption of at least some of the light by the test fluid;

m. separating the collected light from the test fluid into a plurality of parts, each part having a preselected, characteristic wavelength being those same pre-selected wavelengths into which the collected light from the control sample was separated;

n. detecting the relative intensity of the collected light from the test fluid at each of the selected wavelengths;

o. collecting data associated with the test fluid indicating, at least, the relative intensities of the collected light at each of the preselected wavelengths;

p. processing the collected data associated with the test fluid to provide processed data representative of a plurality of mathematical inter-relationships among the relative intensity data associated with the pre-selected wavelengths of the Test fluid;

q. comparing the processed data for the test fluid to said signature which represents the known non-contaminant;

r. determining from the comparison whether or not the tested fluid is unacceptably contaminated.

2. Method of claim 1, wherein the determining step comprises at least the step of determining that some substance dissimilar to the known fluid of the control sample is present in the tested fluid.

3. Method of claim 1, wherein the various steps of collecting light each includes, at least, the step of collecting the light after absorption at a plurality of test times within a predetermined test period;

and wherein the various detecting steps each includes, at least, the step of detecting the relative intensity of the collected light at each of the selected wavelengths, at each of the test times.

4. Method of claim 3, wherein the various steps of processing data each comprise the steps of:

processing the collected data to define at least a second category of data, which second category of data includes at least one of the following;

(1) peak relative intensity ("PI") during the test period for each pre-selected wavelength ("λ

");

or (2) the sum of the relative intensities ("ε

I") of all test times over the test period for each selected wavelength;

or (3) the area under a curve plotted by the coordinates of the relative intensities verses time for each selected wavelength;

or (4) maximum average intensity ("AvI") over the test period for each selected wavelength; and

processing said second category of data to define at least a third category of data, which third category of data includes data defined by normalizing second category data of each pre-selected wavelength to second category data of one of the pre-selected wavelengths as in the manner of PIλ

₂ /PIλ

₁ and PIλ

₃ /PIλ

₁ and PIλ

_n /PIλ

₁, or ε

Iλ

₂ /ε

Iλ

₁ and ε

Iλ

₃ /ε

Iλ

₁ and ε

Iλ

_n /ε

Iλ

₁, or AvIλ

₂ /AvIλ

₁ and AvIλ

₃ /AvIλ

₁ and AvIλ

_n /AvIλ

₁ ; and

wherein the comparing step comprises, at least, the step of comparing the third category of data for the test fluid to similar data for the control sample.

5. Method of claim 4, further comprising the step of interpreting the third category of data to define at least a fourth category of data, which fourth category of data includes data defined by normalizing the third category data for each pre-selected wavelength to the third category data of one of the pre-selected wavelengths, as in the manner of

6. Method of claim 1, further comprising the step of moving the test fluid past a stationary light source.

7. Method of claim 6, further comprising the step of constituting a test fluid in a container;

wherein the container, with the fluid therein, is moved past the light source.

8. Method of claim 7, wherein the container is a plastic bottle.

9. Method of claim 6, wherein the test fluid is moved through a fluid conduit past the stationary light source.

10. Method of claim 1, further comprising the step of moving the light source past a standing test fluid.

11. Method of claim 10, further comprising the step of constituting a test fluid in a container;

and wherein the light source is moved past the container with the fluid therein.

12. Method of claim 11, wherein the container is a plastic bottle.

13. Method of claim 1, further comprising the step of activating a reject mechanism in response to determining that the tested fluid is unacceptably contaminated.

14. Method of claim 1, wherein the various steps of directing light each include, at least, the step of directing a collimated light beam at the respective control sample or test fluid.

15. Method of claim 1, wherein each of the steps of directing light includes, at least, the steps of:

retaining the control samples and test fluid each in similar containers;

passing light into the container through a first wall portion of the container, into the respective control sample or test fluid retained in the container, and out of the container through a second wall portion of the container.

16. Method of claim 1, wherein each of the steps of collecting light includes, at least, one or more of the steps of;

collecting light transmitted through the respective control samples and test fluid;

collecting light reflected by the respective control samples and test fluid; and

/or

collecting light resulting from transflection of light directed at the respective control samples and test fluid.

17. Method of claim 1, wherein the signature provided in the correlating step is in the form of selectively associated, processed data stored within a computer medium.

18. Method of claim 17, wherein signature provided in the correlating step is in the form of a graphically displayed topography.

19. The method of claim 1, wherein the step of correlating data further comprises, at least, the step of correlating the data of all control samples to provide a plurality of "signatures", each signature representing the known non-contaminant by associating processed control data from control samples of different concentration levels at a common temperature or temperature range;

and

wherein the comparing step comprises, at least, the step of comparing the processed data for the test fluid to one or more of the signatures of the plurality of signatures.

20. The method of claim 1, wherein the step of correlating data further comprises, at least, the step of correlating the data of all control samples to provide a plurality of "signatures", each signature representing the known non-contaminant by associating processed control data from control samples of different temperature at a common concentration level;

and

wherein the comparing step comprises, at least, the step of comparing the processed data for the test fluid to one or more of the signatures of the plurality of signatures.

21. Method of claim 1, wherein each of the steps of collecting light includes, at least, one or more of the steps of;

collecting light transmitted through the respective control samples and test solution;

collecting light reflected by the respective control samples and test solution; and

/or

collecting light resulting from transflection of light directed at the respective control samples and test solution.

22. Fluid inspection method, said method comprising the steps of:

a. creating a plurality of control samples of a known, non-contaminated fluid, and

b. modifying each control sample such that each said control sample differs from each of the other control samples by some property, while each control sample continues to consist essentially of the known non-contaminated fluid;

c. as to each control sample, directing light from a light source at the control sample;

d. as to each control sample, collecting light after absorption of at least some of the light by the control sample;

e. as to each control sample, separating the collected light from the control sample into a plurality of pre-selected wavelengths;

f. as to each control sample, detecting the relative intensity of the collected light from the control sample at each of the selected wavelengths;

g. as to each control sample, processing data representative of the detected relative intensities from the control sample to, at least, provide processed data representative of a plurality of mathematical inter-relationships among the relative intensity data associated with all of the selected wavelengths of the control sample;

h. correlating the processed data of two or more of the control samples of the plurality of control samples to provide at least a first control "topography" of processed control data which topography represents the known non-contaminated fluid;

h. directing light from a light source at a fluid to be tested;

i. collecting light after absorption of at least some of the light by the test fluid;

j. separating the collected light from the test fluid into a plurality of wavelengths, said wavelengths being those same pre-selected wavelengths into which the collected light from the control sample was separated;

k. detecting the relative intensity of the collected light from the test fluid at each of the selected wavelengths;

l. processing data representative of the detected relative intensities from the test fluid to, at least, provide processed data representative of a plurality of mathematical inter-relationships among the relative intensity data associated with all of the selected wavelengths of the test fluid;

m. comparing the processed data for the test fluid to the topography which represents the known non-contaminated fluid.

n. determining from the comparison whether or not the test fluid is unacceptably contaminated.

23. Method of claim 22, further comprising the step of constituting the test fluid in a container.

24. Method of claim 22, wherein the step of directing light includes, at least, the steps of directing a collimated light beam at the control sample and directing a collimated light beam at the test fluid.

25. Method of claim 22, further comprising the step of creating relative movement between the light source and the test fluid;

26. Method of claim 25, wherein the steps of directing light and creating a relative movement are interchangeable.

27. Method of claim 22, wherein the fluid to be tested is of uncertain make-up but consists, at least, of a known liquid, and wherein the non-contaminated fluid of the control sample is of known make-up, consisting essentially of a known non-contaminant and the same known liquid.

28. Method of claim 27, wherein the known liquid is water.

29. Method of claim 22, wherein the various steps of collecting light each includes, at least, the step of collecting the light after absorption at a plurality of test times within a predetermined test period;

and wherein the various detecting steps each includes, at least, the step of detecting the relative intensity of the collected light at each of the selected wavelengths, at each of the test times, thereby defining a first category of data including, at least, coordinates of relative light intensity and test times for each of the selected wavelengths.

30. Method of claim 29, wherein the various steps of processing data each comprise the steps of:

processing the collected data to define at least a second category of data, which second category of data includes at least one of the following;

(1) peak relative intensity ("PI") during the test period for each preselected wavelength ("λ

");

or (2) the sum of the relative intensities ("ε

I") of all test times over the test period for each selected wavelength;

or (3) the area (" ") under a curve plotted by the coordinates of the relative intensities verses time for each selected wavelength;

or (4) maximum average intensity ("AvI") over the test period for each selected wavelength; and

processing said second category of data to define at least a third category of data, which third category of data includes data defined by normalizing second category data of each pre-selected wavelength to second category data of one of the pre-selected wavelengths as in the manner of PIλ

₂ /PI λ

₁ and PIλ

₃ /PIλ

₁ and PIλ

_n /PIλ

₁, or ε

Iλ

₂ /ε

Iλ

₁ and ε

Iλ

₃ /ε

Iλ

₁ and ε

Iλ

_n /ε

Iλ

₁, or AvIλ

₂ /AvIλ

₁ and AvIλ

₃ /AvIλ

₁ and AvIλ

_n /AvIλ

₁ ; and

wherein the comparing step comprises, at least, the step of comparing the third category of data for the test fluid to similar data for the control sample.

31. Method of claim 30, further comprising the step of interpreting the third category of data to define at least a fourth category of data, which fourth category of data includes data defined by normalizing the third category data for each pre-selected wavelength to the third category data of one of the pre-selected wavelengths, as in the manner of

32. Method of claim 22, wherein each processing step performed on each of the control samples of the plurality of control samples further comprises, at least, the step of correlating the processed data of the respective control sample to provide at least a first control "signature" associated with the respective control sample, and wherein the step of correlating the processed data of two or more control samples comprises, at least, the step of correlating the control signatures associated with two or more of the control samples to provide at least the first control topography.

33. Method of claim 32, wherein the step of processing data from the test fluid further comprises, at least the step of correlating the processed data of the test fluid to provide at least a first test "signature" which represents the fluid to be tested;

and wherein the comparing step further comprises the step of comparing the test signature to one or more of the control signatures within at least the first topography.

34. Method of claim 33, wherein each of the correlating steps comprises the step of correlating the respective processed data or signatures to provide the respective signature or topography in the form of selectively associated, processed data stored within a computer medium.

35. Method of claim 33, wherein each of the correlating steps comprises the step of correlating the respective processed data or signatures to provide the respective signature or topography in graphically displayed format.

36. Method of claim 22, wherein each processing step performed on each of the control samples of the plurality of control samples further comprises, at least, the step of correlating the processed data of the respective control sample to provide a plurality of control signatures associated with the respective control sample, each control signature associated with each respective control sample relating processed control data representative of one of the mathematical interrelationship of the plurality of interrelationships, each control signature associated with each respective control sample differing from the other control signatures associated with that control sample as to the mathematical interrelationship represented;

and wherein the step of correlating the processed data of two or more control samples to provide at least a first topography comprises the step of correlating the pluralities of control signatures associated with two or more control samples to provide a plurality of topographies of processed data which topographies each represent the known non-contaminated fluid.

37. Method of claim 36, wherein the step of processing data from the test fluid further comprises, at least the step of correlating the processed data of the test fluid to provide a plurality of test signatures, each signature of the plurality of test signatures relating processed test data representative of one of the mathematical interrelationships of the plurality of interrelationships, each test signature differing from the other test signatures as to the mathematical interrelationship represented;

and wherein the comparing step further comprises the step of comparing the test signatures to the control signatures of one or more of the topographies.

38. Method of claim 37, wherein each of the correlating steps comprises the step of correlating the respective processed data or signatures to provide the respective signature or topography in the form of selectively associated, processed data stored within a computer medium.

39. Method of claim 37, wherein each of the correlating steps comprises the step of correlating the respective processed data or signatures to provide the respective signature or topography in graphically displayed format.

40. Method of claim 36, wherein each topography of the plurality of topographies relates signatures which represent similar mathematical relationships.

41. Method of claim 22, wherein the step of modifying each control sample comprises the step of modifying each respective control sample such that each control sample differs from each of the other control samples as to the temperature of the control sample.

42. Method of claim 22, wherein the step of creating a plurality of control samples comprises the step of creating a plurality of control samples of the known, non-contaminated fluid, which known, non-contaminated fluid of each said control sample consists essentially of the same known liquid and/or the same known, non-contaminant;

and

wherein the step of modifying each control sample comprises the step of modifying each control sample such that each said control sample differs from each of the other control samples by some property, while each control sample continues to consist essentially of the known non-contaminant and/or the known liquid; and

wherein the correlating step comprises the step of correlating the processed data of two or more control samples of the plurality of control samples to provide at least a first "topography" of processed control data which topography represents the known non-contaminant; and

wherein the comparing step comprises the step of comparing the processed data for the test fluid to the topography which represents the known non-contaminant.

43. Method of claim 42, wherein each processing step performed on each of the control samples of the plurality of control samples further comprises, at least, the step of correlating the processed data of the respective control sample to provide at least a first control "signature" associated with the respective control sample, and wherein the step of correlating the processed data of two or more control samples comprises, at least, the step of correlating the control signatures associated with two or more of the control samples to provide at least the first control topography.

44. Method of claim 43, wherein the step of processing data from the test fluid further comprises, at least the step of correlating the processed data of the test fluid to provide at least a first test "signature" which represents the fluid to be tested;

and wherein the comparing step further comprises the step of comparing the test signature to one or more of the control signatures within at least the first topography.

45. Method of claim 44, wherein each of the correlating steps comprises the step of correlating the respective processed data or signatures to provide the respective signature or topography in the form of selectively associated, processed data stored within a computer medium.

46. Method of claim 44, wherein each of the correlating steps comprises the step of correlating the respective processed data or signatures to provide the respective signature or topography in graphically displayed format.

47. Method of claim 42, wherein each processing step performed on each of the control samples of the plurality of control samples further comprises, at least, the step of correlating the processed data of the respective control sample to provide a plurality of control signatures associated with the respective control sample, each control signature associated with each respective control sample relating processed control data representative of one of the mathematical interrelationship of the plurality of interrelationships, each control signature associated with each respective control sample differing from the other control signatures associated with that control sample as to the mathematical interrelationship represented;

and wherein the step of correlating the processed data of two or more control samples to provide at least a first topography comprises the step of correlating the pluralities of control signatures associated with two or more control samples to provide a plurality of topographies of processed data which topographies each represent the known non-contaminated fluid.

48. Method of claim 47, wherein the step of processing data from the test fluid further comprises, at least the step of correlating the processed data of the test fluid to provide a plurality of test signatures, each signature of the plurality of test signatures relating processed test data representative of one of the mathematical interrelationships of the plurality of interrelationships, each test signature differing from the other test signatures as to the mathematical interrelationship represented;

and wherein the comparing step further comprises the step of comparing the test signatures to the control signatures of one or more of the topographies.

49. Method of claim 48, wherein each of the correlating steps comprises the step of correlating the respective processed data or signatures to provide the respective signature or topography in the form of selectively associated, processed data stored within a computer medium.

50. Method of claim 48, wherein each of the correlating steps comprises the step of correlating the respective processed data or signatures to provide the respective signature or topography in graphically displayed format.

51. Method of claim 47, wherein each topography of the plurality of topographies relates signatures which represent similar mathematical relationships.

52. Method of claim 42, wherein the step of modifying each control sample comprises the step of modifying each respective control sample such that each control sample differs from each of the other control samples as to one or both of the properties of (i) relative concentrations of the known liquid and the known non-contaminant and/or (ii) the temperature of the control sample.