Radiation thermometer

• US 8,042,997 B2
• Filed: 02/06/2007
• Issued: 10/25/2011
• Est. Priority Date: 02/06/2006
• Status: Active Grant

• Current Assignee: Land Instruments International Ltd. (Ametek Incorporated)
• Original Assignee: Land Instruments International Ltd. (Ametek Incorporated)
• Inventors: Metcalfe, Stuart Francis, Ridley, Ian Hamilton, Lyndon, Adrian John Masefield
• Primary Examiner(s): Fulton; Christopher
• Application Number:
  US12/278,392
• Publication Number:
  US 20090037135A1
• Time in Patent Office: 1,722 Days
• Field of Search: 374/131, 374/121, 250/338.1
• US Class Current: 374/131
• CPC Class Codes: G01J 5/02 Constructional details
• CPC Class Codes: G01J 5/025 Interfacing a pyrometer to an external device or network; User interface
• CPC Class Codes: G01J 5/0265 Handheld, portable ear thermometers G01J5/049
• CPC Class Codes: G01J 5/06 Arrangements for eliminating effects of disturbing radiation; Arrangements for compensating changes in sensitivity for adjusting of solid angle of collected radiation G01J5/07; means for wavelength selection G01J5/0801
• CPC Class Codes: G01J 5/08 Optical arrangements
• CPC Class Codes: G01J 5/0802 Optical filters
• CPC Class Codes: G01J 5/0856 Slit arrangements
• CPC Class Codes: G01J 5/0859 Sighting arrangements, e.g. cameras
• CPC Class Codes: G01J 5/20 using resistors, thermistors or semiconductors sensitive to radiation, e.g. photoconductive devices

Abstract

A radiation thermometer comprising a radiation detector and an optical input path arranged to direct radiation from an object of interest to the radiation detector is disclosed. The radiation detector is adapted to output a signal related to the radiation received from the object of interest, and a processor is adapted to generate temperature measurements from the signal. Filtering means are provided in the optical input path which are arranged to block radiation having a wavelength between approximately 0.92 and 0.98 microns.

Claims

1. A radiation thermometer comprising a radiation detector and an optical input path arranged to direct radiation from an object of interest to the radiation detector, the radiation detector adapted to output a signal related to the radiation received from the object of interest, and a processor adapted to generate temperature measurements from the signal, wherein the radiation thermometer is adapted to detect radiation having wavelengths between approximately 0.85 and 1.10 microns and filtering means are provided in the optical input path and which are arranged to block radiation having a wavelength between approximately 0.92 and 0.98 microns whilst passing radiation having wavelengths less than 0.92 microns and greater than 0.98 microns.

2. A radiation thermometer according to claim 1 wherein, in order for the radiation thermometer to be adapted to detect radiation having wavelengths between approximately 0.85 and 1.10 microns, the filtering means are arranged to additionally block radiation having a wavelength less than approximately 0.85 microns.

3. A radiation thermometer according to claim 1 wherein, in order for the radiation thermometer to be adapted to detect radiation having wavelengths between approximately 0.85 and 1.10 microns, the filtering means are arranged to additionally block radiation having a wavelength more than approximately 1.10 microns.

4. A radiation thermometer according to claim 1 wherein, in order for the radiation thermometer to be adapted to detect radiation having wavelengths between approximately 0.85 and 1.10 microns, the radiation detector is not sensitive to radiation having a wavelength more than approximately 1.10 microns.

5. A radiation thermometer according to claim 1 wherein the filtering means comprise one or more spectral filters.

6. A radiation thermometer according to claim 1 further comprising an objective lens assembly having adjustable separation from a field stop fixed close to the detector, the objective lens assembly being disposed in the optical input path between the object of interest and the filtering means.

7. A radiation thermometer according to claim 1 further comprising a splitter assembly disposed in the optical input path between the object of interest and the filtering means, the splitter assembly adapted to direct a portion of the radiation from the object of interest along an optical viewing path.

8. A radiation thermometer according to claim 7 further comprising a visible-light viewing assembly disposed in the optical viewing path and arranged to generate a visible-light image of the object of interest.

9. A radiation thermometer according to claim 8 wherein the visible-light viewing assembly comprises means for viewing the visible-light image of the object of interest together with a graticule for defining a target area on the visible-light image.

10. A radiation thermometer according to claim 9 further comprising a field-stop aperture disposed in the optical input path.

11. A radiation thermometer according to claim 10 wherein the field stop is adapted to pass only radiation emanating from the target area of the object of interest corresponding to the target area on the visible-light image defined by the graticule.

12. A radiation thermometer according to claim 1 wherein the radiation detector is a semiconductor detector, the semiconductor preferably comprising silicon or InGaAs.

13. A radiation thermometer according to claim 1 wherein the radiation thermometer is portable.

14. A radiation thermometer according to claim 1 further comprising a wireless data connection module for wireless communication with an external device.

15. A radiation thermometer according to claim 14 wherein the wireless data connection module supports the Bluetooth protocol.

16. A radiation thermometer according to claim 15 wherein the wireless data connection is adapted to transmit the temperature measurements generated by the processor to the external device.

17. A radiation thermometer according to claim 16 wherein the wireless data connection is further adapted to transmit at least one parameter used by the processor to generate the temperature measurements from the signal.

18. A radiation thermometer according to claim 17 where in the at least one parameter includes one or more of emissivity data, calibration settings and time constants.

19. A system for monitoring temperature comprising a central processing unit having a wireless data connection module and one or more radiation thermometers according to claim 14 adapted to communicate with the central processing unit.

20. A system for monitoring temperature according to claim 19 wherein the central processing unit is adapted to perform data logging.