Chemically-Selective Detector and Methods Relating Thereto

• US 20090250613A1
• Filed: 04/07/2009
• Published: 10/08/2009
• Est. Priority Date: 04/07/2008
• Status: Active Grant

• Current Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Original Assignee: University of South Carolina
• Inventors: Brooke, Heather, Morgan, Stephen L., Myrick, Michael L.
• Granted Patent: US 8,212,213 B2
• Time in Patent Office: Days
• US Class Current: 250/339.40
• CPC Class Codes: G01J 3/42 Absorption spectrometry; Double beam spectrometry; Flicker spectrometry; Reflection spectrometry beam switching arrangements G01J3/08
• CPC Class Codes: G01J 5/02 Constructional details
• CPC Class Codes: G01J 5/024 Special manufacturing steps or sacrificial layers or layer structures
• CPC Class Codes: G01J 5/08 Optical arrangements
• CPC Class Codes: G01J 5/0802 Optical filters
• CPC Class Codes: G01J 5/0881 Compact construction

Abstract

In accordance with certain embodiments of the present disclosure, a method for adjusting the spectral detectivity of a thermal detector is described. The method includes coating the light sensitive portion of a thermal detector with a first material to reduce the response of the detector. The first material is coated with a second material that is thermally thin and has spectral absorption characteristics. The second material is coated with a third material that is thermally thick, whereby the spectral absorbance of the second material as filtered by the third material primarily determines the thermal conversion of the thermal detector.

Claims

1. A method for adjusting the spectral detectivity of a thermal detector, comprising:

coating the light sensitive portion of a thermal detector with a first material to reduce the response of the detector;

coating the first material with a second material that is thermally thin and has spectral absorption characteristics; and

coating the second material with a third material that is thermally thick,

whereby the spectral absorbance of the second material as filtered by the third material primarily determines the thermal conversion of the thermal detector.

2. The method of claim 1, wherein the first material is a mirror coating material.

3. The method of claim 2, wherein the mirror coating is a metal.

4. The method of claim 3, wherein the metal is gold.

5. The method of claim 1, wherein the second material is a polymer.

6. The method of claim 5, wherein the polymer comprises a near infrared dye.

7. The method of claim 6, wherein the dye absorbs light in the 860 nm spectral region.

8. The method of claim 5, wherein the polymer comprises an acrylic resin.

9. The method of claim 8, wherein acrylic resin comprises an isobutyl methacrylate polymer.

10. The method of claim 1, wherein the thermal detector comprises a thermopile detector.

11. The method of claim 1, wherein the third material is a polymer.

12. The method of claim 1, further comprising:

providing an electrically insulating coating on the light sensitive portion of the thermal detector prior to coating the light sensitive portion with the first material.

13. The method of claim 12, wherein the electrically insulating material is a SiO₂ film.

14. A thermal detector, comprising:

a light sensitive detector material;

a layer of light reflecting material covering at least a portion of the light sensitive material;

a layer of spectral absorption material covering the light reflecting material; and

a layer of filter material covering the spectral absorption material.

15. A thermal detector as in claim 14, further comprising:

a layer of insulating material between said light sensitive material and said light reflecting material.

16. A thermal detector as in claim 14, wherein the light reflecting material is a metal.

17. A thermal detector as in claim 14, wherein the filter material is a polymer.

18. A thermal detector as in claim 14, wherein the spectral absorption material is a polymer.

19. A thermal detector as in claim 17, wherein the polymer comprises an acrylic resin.

20. A method of detecting the presence of a biological fluid, comprising:

utilizing a thermal detector to detect a biological fluid, the thermal detector comprising a light sensitive detector material, a layer of light reflecting material covering at least a portion of the light sensitive material, a layer of spectral absorption material covering the light reflecting material, and a layer of filter material covering the spectral absorption material.