Non-dispersive infrared sensor with a reflective diffuser

• US 8,969,808 B2
• Filed: 06/19/2012
• Issued: 03/03/2015
• Est. Priority Date: 06/19/2012
• Status: Active Grant

• Current Assignee: Amphenol Thermometrics, Inc. (Amphenol Corporation)
• Original Assignee: Amphenol Thermometrics, Inc. (Amphenol Corporation)
• Inventors: Henderson, David Benjamin
• Primary Examiner(s): Porta, David
• Assistant Examiner(s): VALENTINER, JEREMY SCOTT
• Application Number:
  US13/526,589
• Publication Number:
  US 20130334423A1
• Time in Patent Office: 987 Days
• Field of Search: 250/343
• US Class Current: 250/343
• CPC Class Codes: G01N 21/3504 for analysing gases, e.g. multi-gas analysis
• CPC Class Codes: G01N 21/61 Non-dispersive gas analysers G01N21/3504 takes precedence
• CPC Class Codes: G01N 2201/0634 Diffuse illumination
• CPC Class Codes: G01N 2201/0696 Pulsed

Abstract

The present application provides a non-dispersive infrared gas sensor. The non-dispersive infrared gas sensor may include an infrared source, an infrared detector, and a waveguide extending about the infrared source and the infrared detector. The waveguide may include a reflective diffuser thereon.

Claims

1. A non-dispersive infrared gas sensor, comprising:

an infrared source;

an infrared detector; and

a waveguide extending about the infrared source and the infrared detector;

the waveguide comprising a reflective diffuser thereon, wherein the reflective diffuser comprises a printed circuit board reflective surface.

2. The non-dispersive infrared gas sensor of claim 1, wherein the waveguide defines a chamber.

3. The non-dispersive infrared gas sensor of claim 1, wherein the printed circuit board reflective surface comprises a textured surface.

4. The non-dispersive infrared gas sensor of claim 3, wherein the textured surface comprises a random pattern.

5. The non-dispersive infrared gas sensor of claim 3, wherein the textured surface comprises a precision pattern.

6. The non-dispersive infrared gas sensor of claim 3, wherein the reflective diffuser comprises a reflective coating thereon.

7. The non-dispersive infrared gas sensor of claim 1, wherein the printed circuit board reflective surface is formed on a textured thermoplastic component with a reflective metallic coating thereon.

8. The non-dispersive infrared gas sensor of claim 1, wherein the printed circuit board reflective surface comprises a detector reflective surface.

9. The non-dispersive infrared gas sensor of claim 1, wherein the printed circuit board reflective surface comprises a source reflective surface.

10. The non-dispersive infrared gas sensor of claim 1, wherein the printed circuit board reflective surface comprises an electroless nickel immersion gold surface.

11. The non-dispersive infrared gas sensor of claim 1, further comprising a plurality of infrared detectors.

12. The non-dispersive infrared gas sensor of claim 1, further comprising a plurality of infrared detectors spaced apart from each other.

13. The non-dispersive infrared gas sensor of claim 1, further comprising a microprocessor in communication with the infrared source and the infrared detector.

14. A method of measuring a concentration of a gas in a chamber, comprising:

pulsing an infrared signal into the chamber;

scattering the infrared signal off of a reflective diffuser, wherein the reflective diffuser comprises a printed circuit board reflective surface;

receiving the scattered infrared signal at an infrared detector; and

determining the intensity of the scattered infrared signal.

15. A non-dispersive infrared gas sensor, comprising:

an infrared source;

an infrared detector; and

a waveguide extending about the infrared source and the infrared detector;

the waveguide comprising a reflective diffuser with a textured printed circuit board reflective surface and a reflective coating thereon.

16. The non-dispersive infrared gas sensor of claim 15, wherein the textured printed circuit board reflective surface comprises a random pattern or a precision pattern.

17. The non-dispersive infrared gas sensor of claim 15, wherein the textured printed circuit board reflective surface comprises a detector reflective surface.

18. The non-dispersive infrared gas sensor of claim 15, wherein the textured printed circuit board reflective surface comprises a source reflective surface.

19. The non-dispersive infrared gas sensor of claim 15, wherein the textured printed circuit board reflective surface comprises an electroless nickel immersion gold surface.