Multi-channel fluorometric sensor and method of using same

Patent metadata

Field	Value
Publication number	US-9618450-B2
Application number	US-201314039683-A
Country	US
Kind code	B2
Filing date	Sep 27, 2013
Priority date	Sep 27, 2013
Publication date	Apr 11, 2017
Grant date	Apr 11, 2017

Abstract

An optical sensor may include multiple optical emitters configured to emit light into a fluid sample via an optical pathway. Light from the emitters can cause fluorescence from the sample and/or scatter off of the sample. Scattered and fluoresced light can be received by an optical detector in the sensor via the optical pathway, and used to determine at least one characteristic of the fluid sample. A second optical detector can provide reference measurements of the amount of light emitted to the sample. In one example, the optical detector can detect scattered and fluoresced light simultaneously. In another example, light is emitted and detected alternatingly. The sensor can be part of a system that includes one or more controllers configured to control the emitting and detecting of light to and from the fluid sample. The controller can use detected light to determine at least one characteristic of the fluid sample.

First claim

The invention claimed is:

1. An optical sensor comprising:
a housing having an optical pathway configured to direct light through an optical window optically connected to the optical pathway into a fluid sample under analysis and receive light from the fluid sample through the optical window;
a first optical emitter configured to emit light at a first wavelength through the optical pathway and into the fluid sample;
a second optical emitter configured to emit light at a second wavelength different than the first wavelength through the optical pathway and into the fluid sample;
an optical detector configured to receive light from the fluid sample through the optical pathway; and
a controller configured to control the first optical emitter and the second optical to emit light at different times,
wherein the optical detector is configured to receive fluorescent emissions through the optical window from the fluid sample in response to light emitted by the first optical emitter, and the optical detector is configured to receive scattered light through the optical window from the fluid sample in response to light emitted by the second optical emitter.

2. The optical sensor of claim 1 , wherein the optical pathway defines a major axis extending along the length of the optical pathway and the major axis extends through a center of the optical window and a center of the optical detector.

3. The optical sensor of claim 2 , wherein the optical window is an optical lens configured to direct light into the fluid sample from the optical pathway and to receive light from the fluid sample and direct it into the optical pathway.

4. The optical sensor of claim 3 , wherein the optical lens consists essentially of a single ball lens.

5. The optical sensor of claim 1 , wherein the optical pathway defines a first optical pathway and further comprising a second optical pathway intersecting the first optical pathway at an approximately 90 degree angle, wherein the first optical pathway is positioned between the optical window and the optical detector, and the first optical emitter and the second optical emitter are each positioned to emit light into the second optical pathway.

6. The optical sensor of claim 5 , further comprising a partially reflective optical window positioned at an intersection between the first optical pathway and the second optical pathway, wherein the partially reflective optical window is configured to reflect at least a portion of light emitted by the first optical emitter and the second optical emitter from the second optical pathway into the first optical pathway, and the partially reflective optical window is configured to transmit at least a portion of light received from the fluid sample to the optical detector.

7. The optical sensor of claim 6 , further comprising a light guide positioned between the partially reflective optical window and the lens.

8. The optical sensor of claim 7 , wherein the light guide comprises a quartz rod with polished ends.

9. The optical sensor of claim 6 , further comprising a collimating lens positioned between the partially reflective optical window and the optical window.

10. The optical sensor of claim 6 , further comprising a beam dump, positioned so that light from the first and second optical emitters transmitted by the partially reflective optical window is incident thereon, and configured to absorb substantially all incident light emitted by the first and second optical emitters.

11. The optical sensor of claim 6 , wherein the partially reflective optical window comprises a dichroic filter.

12. The optical sensor of claim 5 , wherein the optical detector comprises a first optical detector, and further comprising a second optical detector positioned on an opposite side of the second optical pathway from at least one of the first optical emitter and the second optical emitter.

13. The optical sensor of claim 12 , further comprising a third optical pathway intersecting the second optical pathway at an approximately 90 degree angle, wherein the second optical detector is positioned at a terminal end of the third optical pathway opposite at least one of the first optical emitter and the second optical emitter.

14. The optical sensor of claim 13 , further comprising a partially reflective optical window positioned at an intersection between the second optical pathway and the third optical pathway, wherein the partially reflective optical window is configured to reflect at least a portion of light emitted by the first optical emitter from the second optical pathway into the third optical pathway, and the partially reflective optical window is configured to transmit at least a portion of light emitted by the second optical emitter into the third optical pathway.

15. The optical sensor of claim 14 , wherein the partially reflective optical window comprises a quartz or sapphire window.

16. The optical sensor of claim 15 , wherein the partially reflective optical window comprises an anti-reflective coating for an ultraviolet wavelength range.

17. The optical sensor of claim 12 , further comprising at least one additional optical pathway intersecting the first optical pathway at an approximately 90 degree angle and disposed between the partially reflective optical window and a terminal end of the first optical pathway opposite the optical window, and wherein the first optical detector comprises a plurality of optical detectors, each configured to detect incident light.

18. The optical sensor of claim 17 , further comprising at least one additional partially reflective optical window, each additional partially reflective optical window being positioned at the intersection of the first optical pathway and a corresponding additional optical pathway, and configured to reflect or transmit a select band of light toward at least one corresponding optical detector.

19. The optical sensor of claim 18 , further comprising at least one additional filter, disposed between at least one of the additional partially reflective optical windows and at least one of its corresponding optical detectors.

20. The optical sensor of claim 1 , further comprising a first optical filter positioned between the first optical emitter and the optical window, and a second optical filter positioned between the optical detector and the optical window, wherein the first optical filter is configured to filter out substantially all wavelengths of light within a range of fluorescent light emitted by the fluid sample, and the second optical filter is configured to filter out substantially all wavelengths of light emitted by the first optical emitter but pass wavelengths from the second optical emitter, fluorescent emissions emitted from the fluid sample in response to the light from the first optical emitter, and light scattered by the fluid sample in response to light from the second optical emitter.

21. The optical sensor of claim 1 , wherein the first wavelength ranges from 255 nanometers (nm) to 700 nm, and the second wavelength ranges from 800 nm to 1100 nm.

22. The optical sensor of claim 21 , wherein the first wavelength ranges from 265 nm to 290 nm, and the second wavelength ranges from 800 nm to 900 nm.

23. The optical sensor of claim 1 , wherein the housing is configured to be inserted into a T-section of pipe with the optical window positioned in the fluid sample flowing through the T-section of pipe.

24. The optical sensor of claim 1 , wherein t

Assignees

• Ecolab Usa Inc
• Ecolab Usa Inc

Inventors

• Banks Rodney H
• Tokhtuev Eugene

Classifications

• G01N21/645 Primary

  Specially adapted constructive features of fluorimeters · CPC title

• G01N21/8507

  Probe photometers, i.e. with optical measuring part dipped into fluid sample · CPC title

• G01N21/53

  within a flowing fluid, e.g. smoke · CPC title

• G01N33/1826

  Organic contamination in water · CPC title

• G01N33/184

  Herbicides, pesticides, fungicides, insecticides or the like · CPC title