Duplicative detector sensor

• US 5,841,137 A
• Filed: 07/19/1996
• Issued: 11/24/1998
• Est. Priority Date: 08/11/1995
• Status: Expired due to Term

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Whitney, Julie G.
• Primary Examiner(s): Hannaher, Constantine
• Application Number:
  US08/684,157
• Time in Patent Office: 858 Days
• Field of Search: 250/343, 250/339.02, 250/338.5, 250/338.3
• US Class Current: 250/338.5
• CPC Class Codes: G01J 5/20 using resistors, thermistors or semiconductors sensitive to radiation, e.g. photoconductive devices
• CPC Class Codes: H04N 23/23 from thermal infrared radiation
• CPC Class Codes: H04N 25/671 for non-uniformity detection or correction
• CPC Class Codes: H04N 5/33 Transforming infrared radiation cameras or camera modules for generating image signals from infrared radiation H04N23/20; circuitry of SSIS for transforming infrared radiation into image signals H04N25/20

Abstract

A sensor with multiple radiation detectors with two or more of the detectors sensitive to a common narrow band of radiation and others of the detector not sensitive to this narrow band of radiation. The detectors may be bolometers with bandpass filters over the bolometers.

Claims

1. A gas sensor, comprising:

(a) a radiation source;

(b) a plurality of radiation detectors spaced from said source;

(c) a lid over said radiation detectors;

(d) first and second passband radiation filters on said lid, said first passband radiation filter adjacent a first set of said radiation detectors and said second passband radiation filter adjacent a second set of said radiation detectors with said first and second sets having different numbers of detectors.

2. The gas sensor of claim 1, wherein:

(a) said radiation detectors are arranged in rows and columns within a cavity.

3. The gas sensor of claim 2, wherein:

(a) said cavity has a vapor pressure of less than about 200 mTorr.

4. The gas sensor of claim 1, wherein:

(a) said first passband filter has a center wavelength corresponding to an absorption band of carbon monoxide and said second passband filter has a center wavelength corresponding to an absorption band of carbon dioxide, and said first set has more detectors than said second set.

5. The gas sensor of claim 1, wherein:

(a) said radiation detectors include bolometers.