Infrared radiation sources, sensors and source combinations, and methods of manufacture

• US 7,119,337 B1
• Filed: 07/30/1999
• Issued: 10/10/2006
• Est. Priority Date: 08/04/1997
• Status: Expired due to Fees

• Current Assignee: Flir Surveillance, Inc. (Teledyne Technologies Incorporated)
• Original Assignee: Ion Optics, Inc. (Teledyne Technologies Incorporated)
• Inventors: Johnson, Edward A., Wollam, John S., Daly, James T.
• Primary Examiner(s): Lee, John R.
• Assistant Examiner(s): JOHNSTON, PHILLIP A
• Application Number:
  US09/762,077
• Time in Patent Office: 2,629 Days
• Field of Search: 250/504.R, 250/339.13
• US Class Current: 250/339.13
• CPC Class Codes: G01J 3/02 Details
• CPC Class Codes: G01J 3/0216 using light concentrators or collectors or condensers
• CPC Class Codes: G01J 3/0286 Constructional arrangements for compensating for fluctuations caused by temperature, humidity or pressure, or using cooling or temperature stabilization of parts of the device; Controlling the atmosphere inside a spectrometer, e.g. vacuum
• CPC Class Codes: G01J 3/108 for measurement in the infrared range
• CPC Class Codes: G01J 5/0014 for sensing the radiation from gases, flames
• CPC Class Codes: G01J 5/02 Constructional details
• CPC Class Codes: G01J 5/061 by controlling the temperature of the apparatus or parts thereof, e.g. using cooling means or thermostats
• CPC Class Codes: G01J 5/08 Optical arrangements
• CPC Class Codes: G01J 5/0802 Optical filters
• CPC Class Codes: G01J 5/0806 Focusing or collimating elements, e.g. lenses or concave mirrors
• CPC Class Codes: G01J 5/0808 Convex mirrors
• CPC Class Codes: G01J 5/0815 Light concentrators, collectors or condensers
• CPC Class Codes: G01J 5/0893 Arrangements to attach devices to a pyrometer, i.e. attaching an optical interface; Spatial relative arrangement of optical elements, e.g. folded beam path G01J5/049 takes precedence
• CPC Class Codes: G01J 5/0896 using a light source, e.g. for illuminating a surface
• CPC Class Codes: G01J 5/10 using electric radiation detectors
• CPC Class Codes: G01J 5/20 using resistors, thermistors or semiconductors sensitive to radiation, e.g. photoconductive devices
• CPC Class Codes: G01J 5/53 Reference sources, e.g. standard lamps; Black bodies
• CPC Class Codes: G01J 5/532 using a reference heater of the emissive surface type, e.g. for selectively absorbing materials
• 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 2201/06186 : Resistance heated; wire sources; lamelle sources

Abstract

A blackbody radiation device (110) includes a planar filament emission element (102) and a planar detector (104) for respectively producing and detecting radiation having width dl/1 less than about 0.1 to test a sample gas, where 1 is the wavelength of the radiation; a reflector (108); a window (W); an electrical control (118); and a data output element (116).

Claims

1. A narrow band incoherent radiation emitter detector comprising:

a planar filamental emission/detection element characterized by a predetermined spectral range of emitted/detected radiation and a emission/detection width of dl/1 less than about 0.1, where 1 is the wavelength of said radiation, wherein said emission/detection width is substantially determined by surface features of said emission/detection element.

2. An emitter detector to claim 1 wherein said spectral range includes relatively long wavelengths and excludes relatively short wavelengths.

3. An emitter/detector according to claim 2 wherein said emission/detection width is substantially determined by surface features of said emission/detection element.

4. An emitter/detector according to claim 1 wherein said spectral range is near an infrared absorption line of a predetermined material.

5. An emitter/detector according to claim 4 wherein said emission/detection width is substantially determined by surface features of said emission/detection element.

6. An emitter/detector according to claim 1 wherein said spectral range excludes relatively long wavelengths and relatively short wavelengths and includes a range of intermediate wavelengths therebetween.

7. An emitter/detector according to claim 6 wherein said range of intermediate wavelengths includes an infrared absorption line of a predetermined material.

8. An emitter/detector according to claim 6, further comprising a thermal detector for photons characterized by a wavelength within said intermediate range.

9. An emitter/detector according to claim 6 further comprising a thermal detector for detecting Infrared energy characterized by a wavelength in said intermediate range.

10. An emitter/detector according to claim 6 wherein said emission/detection element is a suspended filament made of a metal foil.

11. An emitter/detector according to claim 6 wherein said emission/detection element is suspended filament made of a back-etched semiconductor.

12. An emitter/detector according to claim 6 wherein said emission/detection element is a resistive element having an emission surface to control said spectral range.

15. A gas detector according to claim 12 further comprising:

D. a processor responsive to said emission/detection element for generating an output signal representative of radiation incident thereon.

13. A gas detector comprising:

A. a planar filamental emission/detection element characterized by a predetermined spectral range of emitted/detected radiation and a emission/detection width dl/1 less than about 0.1, where 1 is the wavelength of said radiation, wherein said emission/detection width is substantially determined by surface features of said emission/detection element, said emission/detection element having an input/output axis, and

B. a first reflector disposed along said input/output axis and opposite to said emission/detection element, whereby an optical path is defined from said emission/detection element to said first reflector to and back to said emission/detection element, wherein said optical path between said emission/detection element and said first reflector passes through a gas test region.

14. A gas detector according to claim 13, further comprising:

C. a driver for driving said emission/detection element to emit radiation propagating along said optical path toward said first reflector.

16. A gas detector according to claim 13 wherein said spectral range includes a wavelength corresponding to an absorption line of a predetermined gas.

17. A gas detector according to claim 13 further comprising:

a second reflector extending from points near said emission/detection element along said input/output axis,

wherein said second reflector is disposed along said optical path, whereby said optical path extends from said emission/detection element to said second reflector to said first reflector to said second reflector to said emission/detection element, and wherein said optical path between said second reflector and said first reflector passes through said gas test region.

18. A gas detector according to claim 17, further comprising:

C. a driver for driving said emission/detection element to emit radiation propagating along said optical path toward said first reflector.

19. A gas detector according to claim 18 further comprising:

D. a processor responsive to said emission/detection element for generating an output signal representative of radiation incident thereon.

20. A gas detector according to claim 17 wherein said second reflector is a beam-forming reflector and said second reflector is substantially planar.

21. A gas detector comprising:

A. a planar filamental emission element characterized by a predetermined spectral range of emitted radiation and an emission width dl/1 less than about 0.1, where 1 is the wavelength of said emission element having an output axis, wherein said emission width is substantially determined by surface features of said emission/detection element,

B. a first reflector disposed along said output axis, and

C. a planar filamental detection element characterized by a predetermined spectral range of detected radiation and an emission/detection width dl/1 less than about 0.1, where 1 is the wavelength of said detection element having an input axis, whereby an optical path is defined from said emission element to said first reflector and to said first detection element, wherein said optical path between said emission element and said first reflector, or between said first reflector and said detection element or both, passes through a gas test region.

22. A gas detector according to claim 21 further comprising:

a second reflector disposed along said optical path between said first reflector and said detection element whereby said optical path extends from said emission element to said first reflector to said reflector to said detection element, and wherein said optical path between said first reflector and said second reflector passes through said gas test region.

23. A gas detector according to claim 21, further comprising:

C. a driver for driving said emission element to emit radiation propagating along said optical path toward said first reflector.

24. A gas detector according to claim 21 further comprising:

D. a processor responsive to said detection element for generating an output signal representative of radiation incident thereon.

25. A gas detector according to claim 21 wherein said spectral range includes a wavelength corresponding to an absorption line of a predetermined gas.

26. A multi-wavelength radiation emitter/detector array comprising:

an array of planar emission/detection elements, each element being characterized by a predetermined spectral range of emitted/detected radiation and an emission/detection width dl/1 less than about 0.1, when 1 is the wavelength of said radiation, wherein each emission/detection width is substantially determined by surface features of each respective emission/detection element.

27. An array according to claim 26 wherein said array is adopted to emit/detect information representative of a planar image.