Monitoring of photo-aging of light-based chemical indicators using illumination-brightness differential scheme

• US 9,261,462 B2
• Filed: 12/13/2012
• Issued: 02/16/2016
• Est. Priority Date: 12/12/2011
• Status: Active Grant

• Current Assignee: Lamotte Chemical Products Company
• Original Assignee: Step Ahead Innovations, Inc.
• Inventors: Clark, James E.
• Primary Examiner(s): Toatley, Gregory J
• Assistant Examiner(s): Underwood, Jarreas C
• Application Number:
  US13/713,773
• Publication Number:
  US 20140017801A1
• Time in Patent Office: 1,160 Days
• Field of Search: 356124-127, 3562391-2398, 356/515
• US Class Current: 1/1
• CPC Class Codes: A01K 63/04 Arrangements for treating water specially adapted to receptacles for live fish
• CPC Class Codes: C02F 1/008 Control or steering systems not provided for elsewhere in subclass C02F
• CPC Class Codes: C02F 2103/42 from bathing facilities, e.g. swimming pools
• CPC Class Codes: C02F 2209/005 Processes using a programmable logic controller [PLC]
• CPC Class Codes: C02F 2209/006 comprising a software program or a logic diagram
• CPC Class Codes: C02F 2209/008 comprising telecommunication features, e.g. modems or antennas
• CPC Class Codes: C02F 2209/06 pH
• CPC Class Codes: C02F 2209/14 NH3-N
• CPC Class Codes: C02F 2209/15 N03-N
• CPC Class Codes: C02F 2209/18 PO4-P
• CPC Class Codes: G01N 2021/758 using reversible reaction
• CPC Class Codes: G01N 2021/7786 Fluorescence
• CPC Class Codes: G01N 2021/7793 Sensor comprising plural indicators
• CPC Class Codes: G01N 21/15 Preventing contamination of the components of the optical system or obstruction of the light path
• CPC Class Codes: G01N 21/6428 Measuring fluorescence of fluorescent products of reactions or of fluorochrome labelled reactive substances, e.g. measuring quenching effects, using measuring "optrodes" in vivo A61B5/00; immunoassay G01N33/53
• CPC Class Codes: G01N 21/77 by observing the effect on a chemical indicator
• CPC Class Codes: G01N 21/78 producing a change of colour
• CPC Class Codes: G01N 21/8507 Probe photometers, i.e. with optical measuring part dipped into fluid sample
• CPC Class Codes: G01N 21/88 Investigating the presence of flaws or contamination
• CPC Class Codes: G01N 2201/127 Calibration; base line adjustment; drift compensation
• CPC Class Codes: G01N 31/22 : using chemical indicators G01N31/02 takes precedence
• CPC Class Codes: G01N 33/18 : Water
• CPC Class Codes: G02B 6/0001 : specially adapted for lighting devices or systems lighting or signalling on vehicles using light guides B60Q1/00; lighting devices for vehicle dashboards B60Q3/10; lighting devices for vehicle interior using light guides B60Q3/62; lighting devices mounted on the vehicle rear part using light guides F21S43/235; measuring arrangements having light conducting pointers G01D13/265; illumination of liquid crystal displays G02F1/1336; illuminated signs G09F13/00
• CPC Class Codes: Y10S 436/805 : Optical property
• CPC Class Codes: Y10S 436/809 : Multifield plates or multicontainer arrays
• CPC Class Codes: Y10T 436/11 : Automated chemical analysis
• CPC Class Codes: Y10T 436/115831 : Condition or time responsive
• CPC Class Codes: Y10T 436/12 : Condition responsive control
• CPC Class Codes: Y10T 436/173076 : Nitrite or nitrate
• CPC Class Codes: Y10T 436/173845 : Amine and quaternary ammonium
• CPC Class Codes: Y10T 436/174614 : Tertiary amine
• CPC Class Codes: Y10T 436/175383 : Ammonia
• CPC Class Codes: Y10T 436/193333 : In aqueous solution
• CPC Class Codes: Y10T 436/207497 : Molecular oxygen
• CPC Class Codes: Y10T 436/25 : including sample preparation
• CPC Class Codes: Y10T 436/25375 : Liberation or purification of sample or separation of material from a sample [e.g., filtering, centrifuging, etc.]

Abstract

Photo-aging monitoring of light-based chemical indicators that experience performance degradation as the cumulative amount of light exposure from measurement and/or reference illumination increases from usage. Differing regions on a chemical indicator are illuminated with measurement illumination light of differing exposures, for example, higher brightness, longer exposure times, or both. Readings from the differing regions are compared with known aging information for the chemical indicator at issue to determine a confidence factor for the measurements. The confidence factor can be used to control various actions relating to measurements acquired from the chemical indicators, such as compensating measurement readings for photo-aging, assigning confidence levels to measurement readings, and issuing alerts to users when photo-aging exceeds one or more predetermined thresholds.

Claims

1. A method of monitoring photo-aging of a chemical indicator in an aquatic-environment monitoring/measuring system, comprising:

taking, over a first period of time and using an optical reading system, a plurality of first optical readings from a first illumination spot on the chemical indicator, wherein each of the first optical readings is based on illuminating the first illumination spot with measurement light that creates a first exposure value;

taking, over a second period of time and using the optical reading system, a plurality of second optical readings from a second illumination spot on the chemical indicator, wherein each of the second optical readings is based on illuminating the second illumination spot with measurement light that creates a second exposure value that is different from the first value so as to create an exposure differential;

generating exposure-differential data as a function of the exposure differential; and

using the exposure-differential data to determine whether or not to take a remedial action relative to measurements acquired from the chemical indicator by the aquatic-environment monitoring/measuring system.

2. A method according to claim 1, wherein said illuminating the first illumination spot includes illuminating the first illumination spot with a first brightness and a duration, and said illuminating the second illumination spot includes illuminating the second illumination spot with a second brightness and the duration, wherein said second brightness is different from the first brightness.

3. A method according to claim 1, wherein said illuminating the first illumination spot includes illuminating the first illumination spot with a brightness and a first duration and said illuminating the second illumination spot includes illuminating the second illumination spot with the brightness and a second duration, wherein said second duration is different from the first duration.

4. A method according to claim 1, wherein said using the exposure-differential data includes comparing the exposure-differential data to reference exposure differential data.

5. A method according to claim 1, wherein said using the exposure-differential data includes assigning a confidence level to the measurements as a function of the exposure-differential data.

6. A method according to claim 1, wherein said using the exposure-differential data includes applying a correction factor as a function of the exposure-differential data.

7. A method according to claim 1, wherein said using the exposure-differential data includes issuing an alert to a user advising of a condition of photo-aging as a function of the exposure-differential data.

8. A method according to claim 1, wherein the chemical indicator is an immobilized dye chemical indicator and said taking the first and second optical readings includes taking the first and second optical readings while the immobilized dye chemical indicator is submerged in an aquatic environment being monitored.

9. A method according to claim 1, further comprising repeating said taking the first optical readings at a plurality of differing first spots and repeating said taking the second optical readings at a plurality of differing second spots so as to generate multi-reading exposure-differential data.

10. A method according to claim 1, wherein said taking of each first optical reading is performed nearly simultaneously with said taking of a corresponding second optical reading.

11. A machine-readable hardware storage medium containing machine-executable instructions for executing a method of monitoring photo-aging of a chemical indicator in an aquatic-environment monitoring/measuring system, said machine-executable instructions comprising:

a first set of machine-executable instructions for taking, over a first period of time and using an optical reading system, a plurality of first optical readings from a first illumination spot on the chemical indicator, wherein each of the first optical readings is based on illuminating the first illumination spot with measurement light that creates a first exposure value;

a second set of machine-executable instructions for taking, over a second period of time and using the optical reading system, a plurality of second optical readings from a second illumination spot on the chemical indicator, wherein each of the second optical readings is based on illuminating the second illumination spot with measurement light that creates a second exposure value that is different from the first value so as to create an exposure differential;

a third set of machine-executable instructions for generating exposure-differential data as a function of the exposure differential; and

a fourth set of machine-executable instructions for using the exposure-differential data to determine whether or not to take a remedial action relative to measurements acquired from the chemical indicator by the aquatic-environment monitoring/measuring system.

12. A machine-readable hardware storage medium according to claim 11, wherein said illuminating the first illumination spot includes illuminating the first illumination spot with a first brightness and a duration, and said illuminating the second illumination spot includes illuminating the second illumination spot with a second brightness and the duration, wherein said second brightness is different from the first brightness.

13. A machine-readable hardware storage medium according to claim 11, wherein said illuminating the first illumination spot includes illuminating the first illumination spot with a brightness and a first duration and said illuminating the second illumination spot includes illuminating the second illumination spot with the brightness and a second duration, wherein said second duration is different from the first duration.

14. A machine-readable hardware storage medium according to claim 11, wherein said fourth set of machine-executable instructions includes machine-executable instructions for comparing the exposure-differential data to reference exposure differential data.

15. A machine-readable hardware storage medium according to claim 11, wherein said fourth set of machine-executable instructions includes machine-executable instructions for assigning a confidence level to the measurements as a function of the exposure-differential data.

16. A machine-readable hardware storage medium according to claim 11, wherein said fourth set of machine-executable instructions includes machine-executable instructions for applying a correction factor as a function of the exposure-differential data.

17. A machine-readable hardware storage medium according to claim 11, wherein said fourth set of machine-executable instructions includes machine-executable instructions for issuing an alert to a user advising of a condition of photo-aging as a function of the exposure-differential data.

18. A machine-readable hardware storage medium according to claim 11, wherein the chemical indicator is an immobilized dye chemical indicator and said first and second sets of machine-executable instructions include machine-executable instructions for taking the first and second optical readings while the immobilized dye chemical indicator is submerged in an aquatic environment being monitored.

19. A machine-readable hardware storage medium according to claim 11, further comprising machine-executable instructions for repeating said taking the first optical readings at a plurality of differing first spots and machine-executable instructions for repeating said taking the second optical readings at a plurality of differing second spots so as to generate multi-reading exposure-differential data.

20. A machine-readable hardware storage medium according to claim 11, wherein said first and second sets of machine-executable instructions include machine-executable instructions for taking each first optical reading nearly simultaneously with taking of a corresponding second optical reading.