Thermopile having reduced thermal noise

• US 5,087,312 A
• Filed: 07/11/1990
• Issued: 02/11/1992
• Est. Priority Date: 07/11/1990
• Status: Expired due to Fees

• Current Assignee: Roche Diabetes Care Inc. (Roche Holding AG)
• Original Assignee: Boehringer Mannheim GmbH (Roche Holding AG)
• Inventors: Gerber, Martin T., Hesketh, Peter J.
• Primary Examiner(s): Hunt, Brooks H.
• Assistant Examiner(s): CARROLL, CHRISMAN DION
• Application Number:
  US07/551,545
• Time in Patent Office: 580 Days
• Field of Search: 136/224, 136/230, 136/231, 136/232, 136/225, 136/233, 136/212
• US Class Current: 136/225
• CPC Class Codes: C12Q 1/001 Enzyme electrodes
• CPC Class Codes: C12Q 1/006 for glucose
• CPC Class Codes: H10N 10/17 characterised by the structure or configuration of the cell or thermocouple forming the device
• CPC Class Codes: H10N 10/817 the junction being non-separable, e.g. being cemented, sintered or soldered

Abstract

Thermopile has a plurality of reference junctions and a plurality of measurement thermocouple junctions connected electrically alternately in series on a dielectric support. Each reference junction has thereover a first medium which is nonthermally responsive and each measurement junction has thereover a second medium which is thermally responsive. The first and second mediums occupy areas which are arranged in a checkerboard pattern, the reference junctions under areas occupied by said first medium each being electrically connected directly to a measurement thermocouple under an area occupied by said second medium.

Claims

1. Thermopile apparatus of the type comprising a plurality of reference junctions and a plurality of measurement thermocouple junctions connected electrically alternately in series on a dielectric support, each said measurement junction having thereover a first medium which is thermally responsive, each said reference junction having thereover a second medium which is non-thermally responsive, characterized in that said first and second mediums occupy areas which are arranged in a checkerboard pattern.

2. Thermopile apparatus as in claim 1 wherein each measurement junction under a first medium is electrically connected directly to a reference junction under an immediately adjacent area occupied by said second medium.

3. Thermopile apparatus as in claim 1 wherein said first medium is black, whereby said first medium is thermally responsive to radiation.

4. Thermopile apparatus as in claim 1 wherein said first medium comprises a reagent layer in which an exothermic chemical reaction occurs.

5. Thermopile apparatus as in claim 4 wherein said reagent layer contains at least one enzyme which catalyzes said chemical reaction.

6. Thermopile apparatus as in claim 5 wherein said enzyme comprises glucose oxidase.

7. Thermopile as in claim 6 wherein said enzyme further comprises catalase.

8. Thermopile apparatus as in claim 1 further comprising a capillary action layer on said first and second mediums to uniformly distribute a sample fluid thereover.

9. Thermopile apparatus as in claim 1 wherein said first and second mediums are arranged on the opposite side of said dielectric support from said reference and measurement junctions respectively.

10. Thermopile apparatus as in claim 8 further comprising thermal insulation means on said reference and measurement junctions.

11. Thermopile apparatus as in claim 1 wherein said dielectric support is a polyimide film.

12. Thermopile apparatus as in claim 1 wherein said junctions each comprise an antimony element electrically connected to a bismuth element.

13. Thermopile apparatus as in claim 11 wherein each thermocouple further comprises a gold pad on the dielectric support, said antimony and bismuth elements being electrically connected to said gold pad.

14. Thermopile apparatus as in claim 13 wherein said dielectric support has a layer of chromium, on which said at least said gold pads are deposited, followed by said antimony and bismuth elements.

15. Thermopile apparatus a in claim 1 wherein said first and second mediums comprise a layer of enzyme gel, said enzyme in said gel being inactivated in the areas over said reference junctions.